Chatchai Trakulrungsi - Academia.edu (original) (raw)
Papers by Chatchai Trakulrungsi
In rats, anosmia induced by olfactory bulbectomy sensitizes the neuroendocrine-reproductive axis ... more In rats, anosmia induced by olfactory bulbectomy sensitizes the neuroendocrine-reproductive axis to the inhibitory effects of the pineal gland. Thus, combined blinding (which stimulates pineal antigonadotrophic activity) and anosmia cause a marked delay in the sexual maturation of female rats. The present study tested whether anosmia would also sensitize the neuroendocrine axis to the reproductive inhibitory effects of melatonin. In the present study, young female rats were rendered anosmic and maintained under 1ight:dark cycles of 14: 10; they were given melatonin injections daily (25 pg) a t either 0900 hr (AM-melatonin) or at 1800 hr (PM-melatonin)-i.e., either 3 or 12 hr after lights on, respectively. The melatonin injections were begun when the rats were 23 days of age and were continued for 35 days. By comparison with AM-melatonin, PM-melatonin injections were considerably more effective in inhibiting bodily growth as well as the weights of the anterior pituitary, ovaries, and uterus of anosmic rats. Similarly, the changes in pituitary and plasma LH and PRL levels were more obvious in the PM-treated anosmic rats than in those given melatonin in the morning. Thus, anosmia does increase the sensitivity of the neuroendocrine-reproductive axis to melatonin, provided the indoleamine is administered late in the light phase of the 1ight:dark cycle. Anosmia by itself had no influence on the daytime levels of radioimmunoassayable melatonin within the pineal gland, whereas in blinded control rats, melatonin levels were markedly augmented.
European Journal of Endocrinology, 1976
The complement fixation immunoassay (CFIA) was used for quantitating growth hormone (GH) in crude... more The complement fixation immunoassay (CFIA) was used for quantitating growth hormone (GH) in crude anterior pituitary extracts from rats subjected to thyroidectomy with or without cortisol and exogenous GH administration. The results obtained from this study were compared with pertinent bioassay (tibia test) results or correlated with the pituitary acidophil cell counts. Whereas it has been reported that pituitary GH levels are normal by the tibia test at 2 weeks after thyroidectomy, the highly specific CFIA method showed an actual 87 % decrement which correlated well with the reduction in acidophils. In addition, the apparently normal content of GH after cortisol administration to thyroidectomized rats, as measured by the tibia test, was contradictory to the very low acidophil population and to the marked reduction in pituitary GH content as measured by the CFIA. Furthermore, theoretical tibia responses illustrate the inconsistency of the bioassay in different experimental condition...
Developmental Aspects International Symposium on Developmental Neurobiology of the Melatonin Rhythm Generating System, Steamboat Springs, Colo., January 1981, 1983
Annales de Biologie Animale Biochimie Biophysique, 1979
Adult female Syrian hamsters (64-82 g) were ovariectomized and thereafter maintained under light ... more Adult female Syrian hamsters (64-82 g) were ovariectomized and thereafter maintained under light : dark cycles of 14 : 10. After 56 days of treatment the animals were killed and pituitary and plasma levels of luteinizing hormone (LH), follicle stimulating hormone (FSH) and prolactin (PRL) were measured by radioimmunoassay. Ovariectomy caused marked rises in both the content and concentration of LH and FSH within the pituitary gland while pituitary PRL levels fell. Plasma levels of LH and FSH also rose while PRL titers remained unchanged. The daily afternoon injection of melatonin (25 ¡ L g subcutaneously) further increased the accumulation of LH and FSH within the pituitary. These responses to daily melatonin injections were prevented if animals additionally received biweekly subcutaneous melatonin-beeswax pellets (1 mg melatonin in 24 mg wax) which presumably released melatonin continually.
Molecular and Cellular Endocrinology, 1978
European Journal of Endocrinology, 1977
The claim has been made that thyrotrophin (TSH) can augment the action of growth hormone (GH) to ... more The claim has been made that thyrotrophin (TSH) can augment the action of growth hormone (GH) to stimulate growth of the epiphysial cartilage plate of the hypophysectomized rat's tibia. The TSH induces its effect via secretion of thyroid hormones which in turn enhance the stimulatory action of GH. If this is true then the employment of the tibia test, whose endpoint is the increase in thickness of the epiphysial cartilage plate in response to GH present either in crude pituitary extracts or relatively purified preparations, which also are likely to contain modest or appreciable quantities of TSH, requires further examination. The present study utilized various fractions of crude pituitary extracts from intact and thyroidectomized rats that respectively contained appreciable quantities of GH or essentially no GH. Fractional aliquots of pituitary extracts from thyroidectomized rats were administered concomitantly with graded doses of exogenous GH to hypophysectomized rats to determine the point at which TSH in the extracts was sufficiently able to stimulate significant tibial plate growth when compared to recipients given GH alone. Purified GH and TSH were also administered in various doses to hypophysectomized recipients in a further attempt to delineate the dose range at which TSH augments the action of GH to promote significant chondrogenesis of the epiphysial plate. The results indicate that the enhancement of the GH effect on the cartilage plate by TSH was evident only when quantities above 100 microng bovine GH were co-administered with 100 mU bovine TSH. As little as 40 mU TSH augmented the growth effect of 400 microng GH on the cartilage plate, demonstrating that smaller quantities of TSH could potentiate larger quantities of GH. These data, therefore, suggest that extracts equivalent to not more than one-half of a normal adult rat's anterior pituitary gland should be administered to hypophysectomized rats for bioassay of GH. Fractions of glands greater than this may contain sufficient amounts of TSH to augment the appreciable quantities of GH already present.
Acta Endocrinologica, Mar 1, 1976
ABSTRACT The complement fixation immunoassay (CFIA) was used for quantitating growth hormone (GH)... more ABSTRACT The complement fixation immunoassay (CFIA) was used for quantitating growth hormone (GH) in crude anterior pituitary extracts from rats subjected to thyroidectomy with or without cortisol and exogenous GH administration. The results obtained from this study were compared with pertinent bioassay (tibia test) results or correlated with the pituitary acidophil cell counts. Whereas it has been reported that pituitary GH levels are normal by the tibia test at 2 weeks after thyroidectomy, the highly specific CFIA method showed an actual 87 % decrement which correlated well with the reduction in acidophils. In addition, the apparently normal content of GH after cortisol administration to thyroidectomized rats, as measured by the tibia test, was contradictory to the very low acidophil population and to the marked reduction in pituitary GH content as measured by the CFIA. Furthermore, theoretical tibia responses illustrate the inconsistency of the bioassay in different experimental conditions. If, as previously suggested, the content of thyrotrophin (TSH) in the crude pituitary extracts renders the bioassay of GH a dubious procedure, then the superiority of immunoassay is obvious.
Rangsit University, 2012
This study aims at developing Multinomial Logistic Regression (MLR) to evaluate the probability o... more This study aims at developing Multinomial Logistic Regression (MLR) to evaluate the probability of breast cancer, proposing MLR to predict five stages of breast cancer (Benign, I, II, III and IV). Nine characteristics of breast cancer: Clump Thickness (X 1); Uniformity of Cell Size (X 2); Uniformity of Cell Shape (X 3); Marginal Adhesion (X 4); Single Epithelial Cell Size (X 5); Bare Nuclei (X 6); Bland Chromatin (X 7); Normal Nucleoli (X 8); and Mitoses (X 9) are used as independent variables. Results show that Multinomial Logistic Regression (MLR) yields a coefficient of a model indicating that X 1 and X 6 have significance less than 0.05. Thus, the prediction of log-likelihood function for a classification staging of breast cancer with P(Y4) of stage IV is a reference category, reducing a model as:
Rangsit University, 2012
The starting point of this paper is the understanding that to date, attempts to integrate graduat... more The starting point of this paper is the understanding that to date, attempts to integrate graduate attributes in academic curricula continue to form lists of isolated skills, with no clear rationale explaining how they are embedded or, indeed, illustrating how they interact with one another to enhance students' learning experiences. While most studies agree that the desired change requires a shift in the curriculum from its predominant focus on content to one that integrates content with process, it is argued here that this refocusing requires a methodology which begins with pedagogy and, therefore, with clear statements regarding the process of knowledge construction that academic curricula support and see as good practice. This objective is in alignment with the understanding that graduate attributes concern themselves with educating students to live in a knowledge society, i.e. with the process of educating. This paper describes a proposal for one such methodology.
Rangsit University, 2014
Cancer can be caused by either endogenous (genetic disorders and impairments of the immune system... more Cancer can be caused by either endogenous (genetic disorders and impairments of the immune system) or exogenous (environmental, carcinogen, infection, and persistent inflammation) factors. Inflammation is an important physiological defense response of the biological system to protect cells or tissues from injury or infection. Acute inflammation occurs over a short duration as part of the normal defense response, while chronic inflammation is a prolonged reaction related to various diseases including carcinogenesis. Many types of immune cells are involved directly or indirectly in chronic inflammation in the production of inflammatory cytokines and it appears that chronic inflammation predisposes susceptible cells to mutation(s). Reactive oxygen species (ROS) are one of the mediators produced by inflammatory cells to eradicate invading pathogens. Persistent production of ROS during chronic inflammation can overcome antioxidant defenses leading to intense oxidative stress. Consequently, cellular structures and DNA become damaged, which is a critical aspect of carcinogenesis. Notwithstanding, ROS can induce apoptotic cell death when cells are exposed at optimum levels and time to ROS. ROS generation through radiotherapy and some types of chemotherapy is therefore a goal of cancer treatment. Care must be taken, however, as ROS can cause serious side-effects. This paradoxical effect of ROS-carcinogenesis vs. cancer therapy-depends on the level intracellular ROS and exposure time. In this review, we reported the associations of chronic inflammation, ROS and carcinogenesis as well as the role of ROS in cancer treatment. The mechanism of the association of ROS with inflammation and carcinogenesis remain inconclusive, so several research studies have focused upon investigating these phenomena.
Rangsit University, 2014
Acute myocardial infarction (AMI) is the most important cause of cardiomyocyte necrosis. Cardiac ... more Acute myocardial infarction (AMI) is the most important cause of cardiomyocyte necrosis. Cardiac troponin (cTn) T and I are structural proteins unique to the heart and have been used as the preferred cardiac biomarkers in the universal definition of myocardial infarction. Cardiac troponins have demonstrated nearly absolute myocardial tissue specificity and high clinical sensitivity for myocardial ischemia. The recent development of high-sensitivity cardiac troponin (hs-cTn) assays allows detection of very low levels of cTn. The hs-cTn assays have improved the diagnostic accuracy and rapid detection of myocardial infarction. Undetectable hs-cTn rules out AMI with a negative predictive value > 99% on emergency department admission. The diagnosis of acute myocardial damage requires a significant change with serial hs-cTn testing. Current consensus for rapid rule-in proposed a 20% increase within 3 to 6 hours when baseline cTn levels are elevated. In addition, relative increases > 50% above the 99 th percentile upper reference limit are found to be the diagnosis of AMI, in the case of negative baseline value. Besides relative change, the absolute values of hs-cTn at emergency department presentation in patients with suspected AMI should be considered as important criteria in the differential diagnosis of the cause of cardiomyocyte damage. Cardiac troponins provide both diagnostic and prognostic information in the setting of acute coronary syndrome (ACS). Elevation of cTn in the absence of ACS should prompt an evaluation for non-thrombotic mechanism of increased cTn levels and direct management at the underlying cause.
Rangsit University, 2014
Lightning protection system in substation may employ mast, shield wire or both. Calculation of li... more Lightning protection system in substation may employ mast, shield wire or both. Calculation of lightning protection zone (LPZ) is based on striking distance to ground, object and mast or shield wires. LPZ generated by mast looks like a tent and is different from that of shield wire. Equipment in substation is safe if it is covered by LPZ. Calculation of the LPZ is complicated especially when there are more masts or parallel/convergence shield wires making it more difficult to picture LPZ. This paper proposes Zone Apportionment Algorithm (ZAA) to apportion the LPZ into two zones corresponding to mast and shield wire, and further sub-apportion in two zones corresponding to non-overlapped and overlapped zones. The maximum height of protected equipment at each point in substation is then calculated. Integrating all points, results in a visual roof representing the LPZ. Equipment with its size and height is then laid in substation. If there is an emerging part above the visual roof, it displays the part that may encounter lightning strikes. ZAA is tested on five cases: one shield wire, two to three parallel shield wires and two to three convergence shield wires. Numerical results show that ZAA can produce visual LPZ correctly in all cases and illustrate verification of protection.
Rangsit University, 2014
In recent years, Songkhla Lake has been increasingly polluted by urban and industrial wastewater ... more In recent years, Songkhla Lake has been increasingly polluted by urban and industrial wastewater draining into the lake through various canals. This study aims to investigate the limitations of wastewater management skills of municipal human resources operating in Songkhla Lake Basin and to explore how to build them up. The survey study was conducted by using a questionnaire and focus group meeting with 21 municipalities located in Songkhla Lake Basin. It was found that most of the representatives (93%) from municipalities working on water pollution in the Basin were faced with domestic wastewater problems. It was also found that 77% and 71% of them had limited knowledge and skills of domestic wastewater management systems and wastewater treatment system designs, respectively. The results also illustrated that 86% and 79% of them wished to learn more about the specific competency of wastewater treatment system management and how to access the data source of wastewater control and its design criteria, respectively. This information will help the concerned academic organizations in Songkhla Lake Basin to further strengthen the knowledge, skills and competency of the municipal human resources who work on water pollution, and guide them in the right direction.
Rangsit University, 2014
The effect of mashing temperature on the quality of wort and beer from Thai rice malt was studied... more The effect of mashing temperature on the quality of wort and beer from Thai rice malt was studied using two non-glutinous rice varieties; Homnin and PathumThani 1. The mashing program was carried out at two different temperatures, 65° and 75°C, for the sugar rest period. It was found that the chemical properties of wort from infusion mash at 65° and 75°C were not different in % extract, reducing sugar and free amino nitrogen contents. However, sugar composition from different worts was significantly different. Sugar composition of wort from infusion mash at 65C gave 8.65 g/100g maltose and 0.98 g/100g glucose while at 75°C gave 3.26 g/100g maltose and 6.70 g/100g glucose. Wort fermentation was prepared in batch sizes of 20 litre (L) using yeast Saccharomyces cerevisiae RSU no.10. The beer qualities of color value, turbidity, pH, and reducing sugar were not different. It was also found that the chemical properties of both beer patterns were the same in quantities of Free Amino Nitrogen (FAN), % extract, % alcohol and bitterness. The bio-functional compounds content corresponded to specification of a healthy beer product which focused on antioxidant, phenolic compound and GABA and were not significantly different, except for the thiamine content remaining in the final product. It was found that thiamine content in beer from infusion mash at 75°C wort was higher than beer from infusion mash at 65°C wort. The sensory evaluation of beers indicated that appearance, aroma, taste, mouth-feel and overall impression of non-alcoholic beer from both beer patterns were judged as drinkable and preferred to the commercial non-alcoholic beer from Germany, namely Clausthaler. The results obtained from this research clearly indicated that non-alcoholic beer from Thai rice malt influenced perception of the consumer and could be used as alternative healthy beverage with an acceptable quality.
Rangsit University, 2014
Germinated parboiled brown rice (GPBR) is the rice that has been soaked, germinated, and steamed ... more Germinated parboiled brown rice (GPBR) is the rice that has been soaked, germinated, and steamed in the husk before drying and then dehusked. The objective of this research was to study the effect of slightly acidic soaking water (pH 5.6) on the inactivation of lipase activity, hence, retarding the rancidity in GPBR. The shelf life of germinated brown rice flour (GBF) was also determined. Results were compared with GPBR produced by the process of the local community (soaking in tap water, pH 7.0). We suggested soaking rough rice in slightly acidic water for 36 h followed by germinating, and steaming to 16 h, and 15 min, respectively. This has been shown to decrease the lipase activity and retard the development of PV and TBA value as compared to the process of the local community. Moreover, the process of soaking in the slightly acidic water for 36 hours promoted GABA content in GPBR to the highest value of 25.70 mg/100 g dry matter. Shelf life of GBF produced from both processes was slightly different, varying between 64-67 days at 30C. When storage temperature increased, different shelf lives of GBF produced from such processes were documented. Soaking rough rice in the slightly acidic water is therefore one method to prevent lipase activity. Other strategies to improve GBF storage stability should focus on methods to inactivate lipoxygenase and lipase activity, thus halting or slowing the early stages of lipid degradation and retard rancidity.
Rangsit University, 2014
In this study, we aimed to provide public-health services from the Faculty of Medical Technology,... more In this study, we aimed to provide public-health services from the Faculty of Medical Technology, Rangsit University, and survey Enterobius vermicularis infections in 3 government schools (N, R, and S school) during the period May-June 2011. Using the Scotch-tape technique, from a population of 977 individuals, 616 (63%) samples were screened and registered as participants. The average rate of infection was 10.4%. S school showed the highest prevalence (14.3%), followed by N school (13.7%); the lowest rate was found in R school (8.0%), but there was no statistically significant difference between the schools (p>0.05). The infection rate was not significantly different between males (10.5%) and females (8.5%) (p>0.05). The highest prevalence was among students in Prathom 2 or aged about 7 years (12.9 %) with the lowest in Prathom 3, or aged about 8 years (6.9%), but the difference between the age groups was not statistically significant (p>0.5). Students who sometimes or always sucked their thumbs had a higher rate of pinworm infection than those who did not; the difference was statistically significant (p<0.5). The highest rate was also found among parents who were agriculturists (13.5%), followed by workers (11.2 %.). No infection was found among parents who worked in government service or government enterprises, or among parents with salaries > 13,000 Baht/month. The average rate of infection from a single examination was still > 10% in government schools in suburban areas. Health education regarding pinworm infection should be implemented in these schools.
Rangsit University, 2014
In this study, the effects of compatibilizer loading on the cure characteristics, thermal and mec... more In this study, the effects of compatibilizer loading on the cure characteristics, thermal and mechanical properties of natural rubber (NR)/synthetic rubber (SR) blends have been investigated. NR was molten and mixed with six synthetic rubbers (butadiene rubber, chloroprene rubber, ethylene-propylene diene rubber, isoprene rubber, nitrile rubber and styrene butadiene rubber) with varied NR/SR weight ratios (100/0, 75/25, 50/50, 25/75 and 0/100) and compatibilizer loadings (0-5 parts per hundred of rubber, phr) on a two roll mill at 70C. The results obtained from differential scanning calorimetry revealed that most of the NR/SR blends both with and without compatibilizer exhibited two glass transition temperatures, indicating that the inclusion of compatibilizers (ENR-25, ENR-50 and Ultrablend-6000) did not improve the compatibility between NR and SRs. However, they could reduce the cure time by 20-50%, as compared to the neat rubber blends, suggesting the reduction in the production energy. Tensile strength of some 50/50 rubber blends with a specific amount and type of compatibilizer improved significantly. Natural rubber/butadiene rubber with 5 phr of ENR-25, natural rubber/chloroprene rubber with 5 phr of ENR-50 and natural rubber/isoprene rubber with 5 phr of Ultrablend-6000 were great examples in terms of improving the mechanical properties.
Rangsit University, 2014
Thailand has made English instruction compulsory at all levels of the education system, including... more Thailand has made English instruction compulsory at all levels of the education system, including the tertiary level. In order to manage the logistics of teaching sometimes thousands of students from a variety of faculties, many Thai universities establish organizations, commonly termed 'language institutes' or 'language centers'. Despite the prevalence and size of these organizations, little research has been done into their management, and their managers. This research thus investigates the management experiences, styles and opinions of 11 language institute directors throughout Thailand as part of a preliminary study. The findings indicate that directors share similar attitudes and experiences, including some forms of resistance, awareness of cultural norms regarding age and status acceptance of the temporariness of the job, high levels of administrative work, and acknowledgement of co-dependency in their team.
Rangsit University, 2014
has under its umbrella 13 research institutes in the variegated field of agriculture and food sci... more has under its umbrella 13 research institutes in the variegated field of agriculture and food sciences. Its largest institute, the NARIC Agricultural Biotechnology Institute (ABC) was founded by the Ministry of Agriculture in 1989. It is widely recognized that there are so many living laboratories like this one in all regions of the world for us to learn and essentially benefit from experience sharing. Thailand is one of the most important global agricultural based countries where agricultural production has been increasing in quantity and quality for more than 4 decades. Due to rapid industrialization and economic oriented national development, the country has gradually evolved into an urbanized economy. However a large part of our national income still derives from the agricultural sectors due to high quality products for consumption and exports in as much as increasing product diversification, continuing growth of specialized farming through appropriate technologies. The growth in agricultural productivity occurred at a time of economic transition and the rise of the manufacturing sector. Labor eventually moved to obtain higher incomes offered by the manufacturing and services industries and other non-agricultural economies. Apart from solving the problems of those who work in the agricultural sectors and increasing their quality of life, there is an urgent need to develop new strategies in enhancing "modernized farming" which essentially required new knowledge gained from R&D in areas such as developing new breeds, cultivation methodology, climatology and agricultural meteorology, geo-informatics for agriculture, precision agriculture, agricultural biotechnology, food technology, and modern farm management. In full realization of the need, Rangsit University through its College of Agricultural Innovation, Food and Biotechnology stands ready to become one of the, "prime movers," in human resource development in the widely integrated field of agriculture, agricultural biotechnology , food sciences and agri-business. We also intend to make our program a living laboratory, not only for students but also for small scale farmers to have access to lifelong learning. I believe there is no boundary in experience sharing, most particularly in the field of agriculture which all human beings have to depend on for survival. I hereby extend my invitation to researchers, agricultural project managers and pilot project investigators to make technical contributions to RJAS which will be most meaningful for us for program upgrading and fulfilling our dream to make Thailand, "The Kitchen of the World," in the long run.
In rats, anosmia induced by olfactory bulbectomy sensitizes the neuroendocrine-reproductive axis ... more In rats, anosmia induced by olfactory bulbectomy sensitizes the neuroendocrine-reproductive axis to the inhibitory effects of the pineal gland. Thus, combined blinding (which stimulates pineal antigonadotrophic activity) and anosmia cause a marked delay in the sexual maturation of female rats. The present study tested whether anosmia would also sensitize the neuroendocrine axis to the reproductive inhibitory effects of melatonin. In the present study, young female rats were rendered anosmic and maintained under 1ight:dark cycles of 14: 10; they were given melatonin injections daily (25 pg) a t either 0900 hr (AM-melatonin) or at 1800 hr (PM-melatonin)-i.e., either 3 or 12 hr after lights on, respectively. The melatonin injections were begun when the rats were 23 days of age and were continued for 35 days. By comparison with AM-melatonin, PM-melatonin injections were considerably more effective in inhibiting bodily growth as well as the weights of the anterior pituitary, ovaries, and uterus of anosmic rats. Similarly, the changes in pituitary and plasma LH and PRL levels were more obvious in the PM-treated anosmic rats than in those given melatonin in the morning. Thus, anosmia does increase the sensitivity of the neuroendocrine-reproductive axis to melatonin, provided the indoleamine is administered late in the light phase of the 1ight:dark cycle. Anosmia by itself had no influence on the daytime levels of radioimmunoassayable melatonin within the pineal gland, whereas in blinded control rats, melatonin levels were markedly augmented.
European Journal of Endocrinology, 1976
The complement fixation immunoassay (CFIA) was used for quantitating growth hormone (GH) in crude... more The complement fixation immunoassay (CFIA) was used for quantitating growth hormone (GH) in crude anterior pituitary extracts from rats subjected to thyroidectomy with or without cortisol and exogenous GH administration. The results obtained from this study were compared with pertinent bioassay (tibia test) results or correlated with the pituitary acidophil cell counts. Whereas it has been reported that pituitary GH levels are normal by the tibia test at 2 weeks after thyroidectomy, the highly specific CFIA method showed an actual 87 % decrement which correlated well with the reduction in acidophils. In addition, the apparently normal content of GH after cortisol administration to thyroidectomized rats, as measured by the tibia test, was contradictory to the very low acidophil population and to the marked reduction in pituitary GH content as measured by the CFIA. Furthermore, theoretical tibia responses illustrate the inconsistency of the bioassay in different experimental condition...
Developmental Aspects International Symposium on Developmental Neurobiology of the Melatonin Rhythm Generating System, Steamboat Springs, Colo., January 1981, 1983
Annales de Biologie Animale Biochimie Biophysique, 1979
Adult female Syrian hamsters (64-82 g) were ovariectomized and thereafter maintained under light ... more Adult female Syrian hamsters (64-82 g) were ovariectomized and thereafter maintained under light : dark cycles of 14 : 10. After 56 days of treatment the animals were killed and pituitary and plasma levels of luteinizing hormone (LH), follicle stimulating hormone (FSH) and prolactin (PRL) were measured by radioimmunoassay. Ovariectomy caused marked rises in both the content and concentration of LH and FSH within the pituitary gland while pituitary PRL levels fell. Plasma levels of LH and FSH also rose while PRL titers remained unchanged. The daily afternoon injection of melatonin (25 ¡ L g subcutaneously) further increased the accumulation of LH and FSH within the pituitary. These responses to daily melatonin injections were prevented if animals additionally received biweekly subcutaneous melatonin-beeswax pellets (1 mg melatonin in 24 mg wax) which presumably released melatonin continually.
Molecular and Cellular Endocrinology, 1978
European Journal of Endocrinology, 1977
The claim has been made that thyrotrophin (TSH) can augment the action of growth hormone (GH) to ... more The claim has been made that thyrotrophin (TSH) can augment the action of growth hormone (GH) to stimulate growth of the epiphysial cartilage plate of the hypophysectomized rat's tibia. The TSH induces its effect via secretion of thyroid hormones which in turn enhance the stimulatory action of GH. If this is true then the employment of the tibia test, whose endpoint is the increase in thickness of the epiphysial cartilage plate in response to GH present either in crude pituitary extracts or relatively purified preparations, which also are likely to contain modest or appreciable quantities of TSH, requires further examination. The present study utilized various fractions of crude pituitary extracts from intact and thyroidectomized rats that respectively contained appreciable quantities of GH or essentially no GH. Fractional aliquots of pituitary extracts from thyroidectomized rats were administered concomitantly with graded doses of exogenous GH to hypophysectomized rats to determine the point at which TSH in the extracts was sufficiently able to stimulate significant tibial plate growth when compared to recipients given GH alone. Purified GH and TSH were also administered in various doses to hypophysectomized recipients in a further attempt to delineate the dose range at which TSH augments the action of GH to promote significant chondrogenesis of the epiphysial plate. The results indicate that the enhancement of the GH effect on the cartilage plate by TSH was evident only when quantities above 100 microng bovine GH were co-administered with 100 mU bovine TSH. As little as 40 mU TSH augmented the growth effect of 400 microng GH on the cartilage plate, demonstrating that smaller quantities of TSH could potentiate larger quantities of GH. These data, therefore, suggest that extracts equivalent to not more than one-half of a normal adult rat's anterior pituitary gland should be administered to hypophysectomized rats for bioassay of GH. Fractions of glands greater than this may contain sufficient amounts of TSH to augment the appreciable quantities of GH already present.
Acta Endocrinologica, Mar 1, 1976
ABSTRACT The complement fixation immunoassay (CFIA) was used for quantitating growth hormone (GH)... more ABSTRACT The complement fixation immunoassay (CFIA) was used for quantitating growth hormone (GH) in crude anterior pituitary extracts from rats subjected to thyroidectomy with or without cortisol and exogenous GH administration. The results obtained from this study were compared with pertinent bioassay (tibia test) results or correlated with the pituitary acidophil cell counts. Whereas it has been reported that pituitary GH levels are normal by the tibia test at 2 weeks after thyroidectomy, the highly specific CFIA method showed an actual 87 % decrement which correlated well with the reduction in acidophils. In addition, the apparently normal content of GH after cortisol administration to thyroidectomized rats, as measured by the tibia test, was contradictory to the very low acidophil population and to the marked reduction in pituitary GH content as measured by the CFIA. Furthermore, theoretical tibia responses illustrate the inconsistency of the bioassay in different experimental conditions. If, as previously suggested, the content of thyrotrophin (TSH) in the crude pituitary extracts renders the bioassay of GH a dubious procedure, then the superiority of immunoassay is obvious.
Rangsit University, 2012
This study aims at developing Multinomial Logistic Regression (MLR) to evaluate the probability o... more This study aims at developing Multinomial Logistic Regression (MLR) to evaluate the probability of breast cancer, proposing MLR to predict five stages of breast cancer (Benign, I, II, III and IV). Nine characteristics of breast cancer: Clump Thickness (X 1); Uniformity of Cell Size (X 2); Uniformity of Cell Shape (X 3); Marginal Adhesion (X 4); Single Epithelial Cell Size (X 5); Bare Nuclei (X 6); Bland Chromatin (X 7); Normal Nucleoli (X 8); and Mitoses (X 9) are used as independent variables. Results show that Multinomial Logistic Regression (MLR) yields a coefficient of a model indicating that X 1 and X 6 have significance less than 0.05. Thus, the prediction of log-likelihood function for a classification staging of breast cancer with P(Y4) of stage IV is a reference category, reducing a model as:
Rangsit University, 2012
The starting point of this paper is the understanding that to date, attempts to integrate graduat... more The starting point of this paper is the understanding that to date, attempts to integrate graduate attributes in academic curricula continue to form lists of isolated skills, with no clear rationale explaining how they are embedded or, indeed, illustrating how they interact with one another to enhance students' learning experiences. While most studies agree that the desired change requires a shift in the curriculum from its predominant focus on content to one that integrates content with process, it is argued here that this refocusing requires a methodology which begins with pedagogy and, therefore, with clear statements regarding the process of knowledge construction that academic curricula support and see as good practice. This objective is in alignment with the understanding that graduate attributes concern themselves with educating students to live in a knowledge society, i.e. with the process of educating. This paper describes a proposal for one such methodology.
Rangsit University, 2014
Cancer can be caused by either endogenous (genetic disorders and impairments of the immune system... more Cancer can be caused by either endogenous (genetic disorders and impairments of the immune system) or exogenous (environmental, carcinogen, infection, and persistent inflammation) factors. Inflammation is an important physiological defense response of the biological system to protect cells or tissues from injury or infection. Acute inflammation occurs over a short duration as part of the normal defense response, while chronic inflammation is a prolonged reaction related to various diseases including carcinogenesis. Many types of immune cells are involved directly or indirectly in chronic inflammation in the production of inflammatory cytokines and it appears that chronic inflammation predisposes susceptible cells to mutation(s). Reactive oxygen species (ROS) are one of the mediators produced by inflammatory cells to eradicate invading pathogens. Persistent production of ROS during chronic inflammation can overcome antioxidant defenses leading to intense oxidative stress. Consequently, cellular structures and DNA become damaged, which is a critical aspect of carcinogenesis. Notwithstanding, ROS can induce apoptotic cell death when cells are exposed at optimum levels and time to ROS. ROS generation through radiotherapy and some types of chemotherapy is therefore a goal of cancer treatment. Care must be taken, however, as ROS can cause serious side-effects. This paradoxical effect of ROS-carcinogenesis vs. cancer therapy-depends on the level intracellular ROS and exposure time. In this review, we reported the associations of chronic inflammation, ROS and carcinogenesis as well as the role of ROS in cancer treatment. The mechanism of the association of ROS with inflammation and carcinogenesis remain inconclusive, so several research studies have focused upon investigating these phenomena.
Rangsit University, 2014
Acute myocardial infarction (AMI) is the most important cause of cardiomyocyte necrosis. Cardiac ... more Acute myocardial infarction (AMI) is the most important cause of cardiomyocyte necrosis. Cardiac troponin (cTn) T and I are structural proteins unique to the heart and have been used as the preferred cardiac biomarkers in the universal definition of myocardial infarction. Cardiac troponins have demonstrated nearly absolute myocardial tissue specificity and high clinical sensitivity for myocardial ischemia. The recent development of high-sensitivity cardiac troponin (hs-cTn) assays allows detection of very low levels of cTn. The hs-cTn assays have improved the diagnostic accuracy and rapid detection of myocardial infarction. Undetectable hs-cTn rules out AMI with a negative predictive value > 99% on emergency department admission. The diagnosis of acute myocardial damage requires a significant change with serial hs-cTn testing. Current consensus for rapid rule-in proposed a 20% increase within 3 to 6 hours when baseline cTn levels are elevated. In addition, relative increases > 50% above the 99 th percentile upper reference limit are found to be the diagnosis of AMI, in the case of negative baseline value. Besides relative change, the absolute values of hs-cTn at emergency department presentation in patients with suspected AMI should be considered as important criteria in the differential diagnosis of the cause of cardiomyocyte damage. Cardiac troponins provide both diagnostic and prognostic information in the setting of acute coronary syndrome (ACS). Elevation of cTn in the absence of ACS should prompt an evaluation for non-thrombotic mechanism of increased cTn levels and direct management at the underlying cause.
Rangsit University, 2014
Lightning protection system in substation may employ mast, shield wire or both. Calculation of li... more Lightning protection system in substation may employ mast, shield wire or both. Calculation of lightning protection zone (LPZ) is based on striking distance to ground, object and mast or shield wires. LPZ generated by mast looks like a tent and is different from that of shield wire. Equipment in substation is safe if it is covered by LPZ. Calculation of the LPZ is complicated especially when there are more masts or parallel/convergence shield wires making it more difficult to picture LPZ. This paper proposes Zone Apportionment Algorithm (ZAA) to apportion the LPZ into two zones corresponding to mast and shield wire, and further sub-apportion in two zones corresponding to non-overlapped and overlapped zones. The maximum height of protected equipment at each point in substation is then calculated. Integrating all points, results in a visual roof representing the LPZ. Equipment with its size and height is then laid in substation. If there is an emerging part above the visual roof, it displays the part that may encounter lightning strikes. ZAA is tested on five cases: one shield wire, two to three parallel shield wires and two to three convergence shield wires. Numerical results show that ZAA can produce visual LPZ correctly in all cases and illustrate verification of protection.
Rangsit University, 2014
In recent years, Songkhla Lake has been increasingly polluted by urban and industrial wastewater ... more In recent years, Songkhla Lake has been increasingly polluted by urban and industrial wastewater draining into the lake through various canals. This study aims to investigate the limitations of wastewater management skills of municipal human resources operating in Songkhla Lake Basin and to explore how to build them up. The survey study was conducted by using a questionnaire and focus group meeting with 21 municipalities located in Songkhla Lake Basin. It was found that most of the representatives (93%) from municipalities working on water pollution in the Basin were faced with domestic wastewater problems. It was also found that 77% and 71% of them had limited knowledge and skills of domestic wastewater management systems and wastewater treatment system designs, respectively. The results also illustrated that 86% and 79% of them wished to learn more about the specific competency of wastewater treatment system management and how to access the data source of wastewater control and its design criteria, respectively. This information will help the concerned academic organizations in Songkhla Lake Basin to further strengthen the knowledge, skills and competency of the municipal human resources who work on water pollution, and guide them in the right direction.
Rangsit University, 2014
The effect of mashing temperature on the quality of wort and beer from Thai rice malt was studied... more The effect of mashing temperature on the quality of wort and beer from Thai rice malt was studied using two non-glutinous rice varieties; Homnin and PathumThani 1. The mashing program was carried out at two different temperatures, 65° and 75°C, for the sugar rest period. It was found that the chemical properties of wort from infusion mash at 65° and 75°C were not different in % extract, reducing sugar and free amino nitrogen contents. However, sugar composition from different worts was significantly different. Sugar composition of wort from infusion mash at 65C gave 8.65 g/100g maltose and 0.98 g/100g glucose while at 75°C gave 3.26 g/100g maltose and 6.70 g/100g glucose. Wort fermentation was prepared in batch sizes of 20 litre (L) using yeast Saccharomyces cerevisiae RSU no.10. The beer qualities of color value, turbidity, pH, and reducing sugar were not different. It was also found that the chemical properties of both beer patterns were the same in quantities of Free Amino Nitrogen (FAN), % extract, % alcohol and bitterness. The bio-functional compounds content corresponded to specification of a healthy beer product which focused on antioxidant, phenolic compound and GABA and were not significantly different, except for the thiamine content remaining in the final product. It was found that thiamine content in beer from infusion mash at 75°C wort was higher than beer from infusion mash at 65°C wort. The sensory evaluation of beers indicated that appearance, aroma, taste, mouth-feel and overall impression of non-alcoholic beer from both beer patterns were judged as drinkable and preferred to the commercial non-alcoholic beer from Germany, namely Clausthaler. The results obtained from this research clearly indicated that non-alcoholic beer from Thai rice malt influenced perception of the consumer and could be used as alternative healthy beverage with an acceptable quality.
Rangsit University, 2014
Germinated parboiled brown rice (GPBR) is the rice that has been soaked, germinated, and steamed ... more Germinated parboiled brown rice (GPBR) is the rice that has been soaked, germinated, and steamed in the husk before drying and then dehusked. The objective of this research was to study the effect of slightly acidic soaking water (pH 5.6) on the inactivation of lipase activity, hence, retarding the rancidity in GPBR. The shelf life of germinated brown rice flour (GBF) was also determined. Results were compared with GPBR produced by the process of the local community (soaking in tap water, pH 7.0). We suggested soaking rough rice in slightly acidic water for 36 h followed by germinating, and steaming to 16 h, and 15 min, respectively. This has been shown to decrease the lipase activity and retard the development of PV and TBA value as compared to the process of the local community. Moreover, the process of soaking in the slightly acidic water for 36 hours promoted GABA content in GPBR to the highest value of 25.70 mg/100 g dry matter. Shelf life of GBF produced from both processes was slightly different, varying between 64-67 days at 30C. When storage temperature increased, different shelf lives of GBF produced from such processes were documented. Soaking rough rice in the slightly acidic water is therefore one method to prevent lipase activity. Other strategies to improve GBF storage stability should focus on methods to inactivate lipoxygenase and lipase activity, thus halting or slowing the early stages of lipid degradation and retard rancidity.
Rangsit University, 2014
In this study, we aimed to provide public-health services from the Faculty of Medical Technology,... more In this study, we aimed to provide public-health services from the Faculty of Medical Technology, Rangsit University, and survey Enterobius vermicularis infections in 3 government schools (N, R, and S school) during the period May-June 2011. Using the Scotch-tape technique, from a population of 977 individuals, 616 (63%) samples were screened and registered as participants. The average rate of infection was 10.4%. S school showed the highest prevalence (14.3%), followed by N school (13.7%); the lowest rate was found in R school (8.0%), but there was no statistically significant difference between the schools (p>0.05). The infection rate was not significantly different between males (10.5%) and females (8.5%) (p>0.05). The highest prevalence was among students in Prathom 2 or aged about 7 years (12.9 %) with the lowest in Prathom 3, or aged about 8 years (6.9%), but the difference between the age groups was not statistically significant (p>0.5). Students who sometimes or always sucked their thumbs had a higher rate of pinworm infection than those who did not; the difference was statistically significant (p<0.5). The highest rate was also found among parents who were agriculturists (13.5%), followed by workers (11.2 %.). No infection was found among parents who worked in government service or government enterprises, or among parents with salaries > 13,000 Baht/month. The average rate of infection from a single examination was still > 10% in government schools in suburban areas. Health education regarding pinworm infection should be implemented in these schools.
Rangsit University, 2014
In this study, the effects of compatibilizer loading on the cure characteristics, thermal and mec... more In this study, the effects of compatibilizer loading on the cure characteristics, thermal and mechanical properties of natural rubber (NR)/synthetic rubber (SR) blends have been investigated. NR was molten and mixed with six synthetic rubbers (butadiene rubber, chloroprene rubber, ethylene-propylene diene rubber, isoprene rubber, nitrile rubber and styrene butadiene rubber) with varied NR/SR weight ratios (100/0, 75/25, 50/50, 25/75 and 0/100) and compatibilizer loadings (0-5 parts per hundred of rubber, phr) on a two roll mill at 70C. The results obtained from differential scanning calorimetry revealed that most of the NR/SR blends both with and without compatibilizer exhibited two glass transition temperatures, indicating that the inclusion of compatibilizers (ENR-25, ENR-50 and Ultrablend-6000) did not improve the compatibility between NR and SRs. However, they could reduce the cure time by 20-50%, as compared to the neat rubber blends, suggesting the reduction in the production energy. Tensile strength of some 50/50 rubber blends with a specific amount and type of compatibilizer improved significantly. Natural rubber/butadiene rubber with 5 phr of ENR-25, natural rubber/chloroprene rubber with 5 phr of ENR-50 and natural rubber/isoprene rubber with 5 phr of Ultrablend-6000 were great examples in terms of improving the mechanical properties.
Rangsit University, 2014
Thailand has made English instruction compulsory at all levels of the education system, including... more Thailand has made English instruction compulsory at all levels of the education system, including the tertiary level. In order to manage the logistics of teaching sometimes thousands of students from a variety of faculties, many Thai universities establish organizations, commonly termed 'language institutes' or 'language centers'. Despite the prevalence and size of these organizations, little research has been done into their management, and their managers. This research thus investigates the management experiences, styles and opinions of 11 language institute directors throughout Thailand as part of a preliminary study. The findings indicate that directors share similar attitudes and experiences, including some forms of resistance, awareness of cultural norms regarding age and status acceptance of the temporariness of the job, high levels of administrative work, and acknowledgement of co-dependency in their team.
Rangsit University, 2014
has under its umbrella 13 research institutes in the variegated field of agriculture and food sci... more has under its umbrella 13 research institutes in the variegated field of agriculture and food sciences. Its largest institute, the NARIC Agricultural Biotechnology Institute (ABC) was founded by the Ministry of Agriculture in 1989. It is widely recognized that there are so many living laboratories like this one in all regions of the world for us to learn and essentially benefit from experience sharing. Thailand is one of the most important global agricultural based countries where agricultural production has been increasing in quantity and quality for more than 4 decades. Due to rapid industrialization and economic oriented national development, the country has gradually evolved into an urbanized economy. However a large part of our national income still derives from the agricultural sectors due to high quality products for consumption and exports in as much as increasing product diversification, continuing growth of specialized farming through appropriate technologies. The growth in agricultural productivity occurred at a time of economic transition and the rise of the manufacturing sector. Labor eventually moved to obtain higher incomes offered by the manufacturing and services industries and other non-agricultural economies. Apart from solving the problems of those who work in the agricultural sectors and increasing their quality of life, there is an urgent need to develop new strategies in enhancing "modernized farming" which essentially required new knowledge gained from R&D in areas such as developing new breeds, cultivation methodology, climatology and agricultural meteorology, geo-informatics for agriculture, precision agriculture, agricultural biotechnology, food technology, and modern farm management. In full realization of the need, Rangsit University through its College of Agricultural Innovation, Food and Biotechnology stands ready to become one of the, "prime movers," in human resource development in the widely integrated field of agriculture, agricultural biotechnology , food sciences and agri-business. We also intend to make our program a living laboratory, not only for students but also for small scale farmers to have access to lifelong learning. I believe there is no boundary in experience sharing, most particularly in the field of agriculture which all human beings have to depend on for survival. I hereby extend my invitation to researchers, agricultural project managers and pilot project investigators to make technical contributions to RJAS which will be most meaningful for us for program upgrading and fulfilling our dream to make Thailand, "The Kitchen of the World," in the long run.