Misbahul Arfin - Academia.edu (original) (raw)

Papers by Misbahul Arfin

Research paper thumbnail of Association of Functional Polymorphism in Protein Tyrosine Phosphatase Nonreceptor 22 (PTPN22) Gene with Vitiligo

Biomarker Insights, 2020

The protein tyrosine phosphatase nonreceptor 22 (PTPN22) is associated with susceptibility to aut... more The protein tyrosine phosphatase nonreceptor 22 (PTPN22) is associated with susceptibility to autoimmune diseases. The functional polymorphism in PTPN22 at 1857 is a strong risk factor for vitiligo susceptibility in Europeans; however, controversy exits in other populations. Present study was aimed to determine whether the PTPN22 C1857T polymorphism confers susceptibility to vitiligo in Saudi Arabians. Genomic DNA was extracted and amplified using tetra primer amplification-refractory mutation system polymerase chain reaction (ARMS-PCR) method. The frequencies of allele T and genotype CT of PTPN22 C1858T polymorphism were significantly higher, whereas those of allele C and genotype CC were lower in patients as compared with controls (P < 0.0001). The genotype TT was absent in both the patients and controls. It is concluded that PTPN22 C1858T polymorphism is strongly associated with vitiligo susceptibility. However, additional studies are warranted using large number of samples from different ethnicities and geographical areas.

Research paper thumbnail of Association of tumor necrosis factor-&alpha; and -&beta; gene polymorphisms in inflammatory bowel disease

Journal of Inflammation Research, Jun 1, 2016

Inflammatory bowel disease (IBD) is a complex, multifactorial, chronic inflammatory disorder of t... more Inflammatory bowel disease (IBD) is a complex, multifactorial, chronic inflammatory disorder of the gastrointestinal tract in which immune dysregulation caused by genetic and/or environmental factors plays an important role. The aim of this casecontrol study was to evaluate the association of tumor necrosis factor-alpha (TNF-α) (308) and-β (+252) polymorphisms with susceptibility of IBD. A total of 379 Saudi subjects including 179 IBD patients (ulcerative colitis (UC) =84 and Crohn's disease (CD) =95) and 200 age-and sex-matched healthy controls were recruited. TNF-a and TNF-b genes were amplified using an amplification refractory mutation systems polymerase chain reaction methodology to detect TNF-α (-308) and-β (+252) polymorphisms. The frequency of the GA genotype of TNF-α (-308G/A) was higher, and the frequencies of the GG and AA genotypes were significantly lower in IBD patients compared with those in controls, indicating that genotype GA-positive individuals are susceptible to IBD and that the GG and AA genotypes exert a protective effect. The frequency of allele A of TNF-α (-308G/A) was significantly higher and that of allele G was lower in IBD patients compared with those in controls, indicating an association of allele A with IBD risk in Saudi patients. On stratification of IBD patients into UC and CD, an almost similar pattern was noticed in both the groups. The results of TNF-β (+252A/G) polymorphisms showed a significant increase in the frequency of the GG genotype in IBD patients, suggesting a positive association of GG genotype with IBD risk. On stratification of IBD patients into UC and CD, the genotype GG of TNF-β was associated with susceptibility risk to UC but not CD. The frequencies of alleles and genotypes of both TNF-α and-β polymorphisms are not affected by sex or type of IBD (familial or sporadic). TNF-α (-308G/A) and TNF-β (+252A/G) polymorphisms are associated with risk of developing IBD in Saudi population.

Research paper thumbnail of Association of Interleukin-10 Gene Promoter Polymorphisms in Saudi Patients with Vitiligo

Disease Markers, 2008

The promoter region of human Interleukin-10 gene is highly polymorphic and has been associated wi... more The promoter region of human Interleukin-10 gene is highly polymorphic and has been associated with numerous autoimmune diseases. Recent studies have linked vitiligo with defective autoimmune system. This study is aimed to explore a possible association between IL-10 gene polymorphism and vitiligo in Saudi population. This case control study consisted of 184 Saudi subjects including 83 vitiligo patients (40 males, 43 females mean age 27.85 ± 12.43 years) and 101 matched controls. Genomic DNA was extracted from the blood samples of healthy controls and Vitiligo patients visiting out patient clinic of Department of Dermatology, Riyadh Armed Forces Hospital, using QIA amp R DNA mini kit (Qiagen CA, USA). Interleukin-10 gene was amplified by polymerase chain reaction (PCR) using Arms primers to detect any polymorphism involved at positions −592, −819 and −1082. The frequencies of GG genotype at −1082, and CC genotype at positions −592 and 819 were significantly higher in vitiligo patients compared to healthy subjects suggesting that GG and CC genotypes might be susceptible to vitiligo in Saudis. On the other hand genotypes −1082 GA, −819 CT, and −592 CA of IL-10 were more prevalent in healthy controls suggesting protective effects of GA, CT and CA genotypes against vitiligo. This study indicates that the IL-10 gene may play a significant role in the etiology of vitiligo among Saudis.

Research paper thumbnail of Association of genetic polymorphisms in interferon-γ, interleukin-6 and transforming growth factor-β1 gene with oral lichen planus susceptibility

BMC Oral Health, Aug 20, 2016

Background: Oral lichen planus (OLP) is a premalignant mucocutaneous disease in which genetic fac... more Background: Oral lichen planus (OLP) is a premalignant mucocutaneous disease in which genetic factors and immune responses play a major role. Cytokines play an important role in the pathogenesis and disease progression of OLP. The aim of this study was to investigate the impact of gene polymorphisms of T helper cell subtype Th1 and Th2 cytokines, interferon-gamma (IFN-γ), interleukin-6 (IL-6) and transforming growth factor (TGF)-β1 on OLP susceptibility in a Saudi cohort. Methods: Forty two unrelated patients with OLP and 195 healthy controls were genotyped for IFN-γ (874A/T), IL-6 (174G/C) and TGF-β1 (509C/T) polymorphisms. Results: The frequency of genotype AT of IFN-γ (874A/T) was significantly higher while genotype AA was lower in OLP patients as compared to controls (P < 0.05). The frequency of T containing genotypes (AT + TT) was also higher in OLP patients as compared to that in controls (P = 0.003). The frequencies of allele T was higher while that of allele A lower in patients than the controls however the difference was not statistically significant (P = 0.07). There was no significant difference in the frequencies of alleles and genotypes of IL-6 (174G/C) and TGF-β1 (509C/T) polymorphisms between patient and control groups. These results indicated that genotype AT of IFN-γ (874A/T) polymorphism is associated with OLP risk and genotype AA is protective to OLP. On the other hand the polymorphisms IL-6 (174G/C) and TGF-β1 (509C/T) may not be associated with OLP risk in our population. Conclusion: It is concluded that IFN-γ (874A/T) polymorphism is associated with the susceptibility of OLP, however further studies with large sample size involving different ethnic populations should be conducted to strengthen our results.

Research paper thumbnail of Systemic lupus erythematosus and infections: a retrospective study in Saudis

Lupus, Sep 1, 2007

This study demonstrates demographic, clinical and laboratory characteristics with special referen... more This study demonstrates demographic, clinical and laboratory characteristics with special reference to infections in Saudi patients with SLE. One-hundred and ninety-nine patients with SLE treated at Riyadh Armed Forces Hospital, Saudi Arabia over a period of 15 years (1990-2005) were retrospectively reviewed. There were 162 females and 37 males (4.4 : 1) with an average age of 35 years at onset of disease. Duration of diseases ranged from one to 23 years with a mean of 7.23 years. Some of the clinical characteristics of SLE patients observed were nephritis (53.7%), fever (53.26%), neuropsychological disorder (36.18%), malar/butterfly rash (27.6%), pulmonary disorder (22.6%), photosensitivity (21.6%), cardiac involvement (21.1%) and oral ulcers (19.09%). Infection was the major complication with 58.79% of SLE patient having suffered from various infections. A total of 22 species of pathogens including gram positive and gram negative bacteria, viruses and fungi were isolated from 117 SLE patients. Single to multiple episode of infection with various pathogens were recorded however, majority of patients harboured one or two species of pathogens. Bacterial infection was predominant (78.6%) followed by viral (28.2%) and fungal (28.2%) infections. Forty-four percent of SLE patients were found to be infected with organisms classified as opportunistic. The high incidence of infections in SLE patients may be attributed to the multiple intrinsic and extrinsic risk factors including deficiency of complement (C3 and C4), disease activity, renal impairment, use of glucocorticoid and cytotoxic drugs. It is concluded that more judicious use of corticosteroids and other immunosuppressive agents will be critical to limit the infections in SLE and a high alert and close monitoring of patients will ensure optimal patient outcome, both in terms of morbidity and mortality.

Research paper thumbnail of Association of tumor necrosis factor-α and -β gene polymorphisms in inflammatory bowel disease

Research paper thumbnail of Larval digenea of Melanoides tuberculatus (Muller,1774) (Gastropoda: Prosobranchia) from Al-Hassa province, Saudi Arabia

Research paper thumbnail of Occurrence of larval Philophthalmus gralli (Mathis and Leger, 1910) in freshwater snail Melanoides tuberculatus (Muller) from Al-Hafuf, Saudi Arabia and its development into adult in various experimental hosts

Parasitology International, 1997

This is the first report of occurrence of Philophthalmus gralli in Melanoides tuberculatus from S... more This is the first report of occurrence of Philophthalmus gralli in Melanoides tuberculatus from Saudi Arabia. The overall infection rate of M. tuberculatus with P. gralli larvae was 8.9%. However, the incidence of infection varied from 6.46 to 10.16% depending on the size of the snail, and larger snails were found to be more infected than the smaller ones. The emerging cercariae encysted on the surface of water which were excysted in vitro and inoculated in the eyes of various experimental hosts. Metacercariae transformed into mature adults in the eyes of chicken, pigeons and quails but failed to develop in mice and rabbits. There was rapid growth in size up to 30 days post-infection (Pi). First egg appeared 13 days Pi, but mature worms having eggs containing fully developed miracidium were obtained 30 days Pi. P. gralli which developed in chicken, pigeons and quails were not uniform in body dimensions, especially those of gonads, indicating the effects of host on development. Moreover, development was found to be retarded in crowded conditions. Migration of worms from one eye to the other occurred in 25% of infections.

Research paper thumbnail of In vitro Excystation of Metacercariae of Clinostomum complanatum (Rudolphi, 1819) (Digenea: Clinostomatidae)

Acta Zoologica, 1988

ABSTRACT In vitro excystation of metacercariae of Clinostomum complanatum (Rudolphi, 1819) was st... more ABSTRACT In vitro excystation of metacercariae of Clinostomum complanatum (Rudolphi, 1819) was studied. Excystation was an active process, initiated by a rise in temperature. The metacercariae excysted in enzymic as well as non enzymic medium, but the rate of excystation was affected by the temperature and/or pH of the medium. The optimal excystation was obtained in pepsin-Tyrode at pH 2.3-3.5 and a temperature of 42°C. Trypsin treatment was not required.

Research paper thumbnail of Apolipoprotein E polymorphisms and primary glaucoma in Saudis

Molecular vision, 2009

The frequencies of apolipoprotein E (APOE) alleles and genotypes were examined in 230 Saudi subje... more The frequencies of apolipoprotein E (APOE) alleles and genotypes were examined in 230 Saudi subjects including primary open-angle glaucoma (POAG; n=60) and primary angle-closure glaucoma (PACG; n=40) patients as well as 130 control subjects. The presence of glaucoma in patients was based on clinical examination and/or ophthalmic records. The APOE allele frequency (epsilon2, epsilon3, and epsilon4) was studied by polymerase chain reaction (PCR) followed by reverse-hybridization and restriction fragment length polymorphism techniques. Analysis of data showed a complete absence of epsilon2 allele and a significantly lower frequency of the epsilon3 allele in primary glaucoma patients (90.5%) compared to the control subjects (95.7%, p=0.034, relative risk [RR]=0.473, protective fraction [PF]=0.318). The frequency of the epsilon4 allele was significantly higher in the glaucoma patients (9.5%) compared to the control subjects (4.2%, p=0.034, RR=2.169, etiological fraction [EF]=0.329). The ...

Research paper thumbnail of Association of TNF-α and TNF-β Gene Polymorphisms with Primary Open Angle and Primary Angle Closure Glaucoma

Research paper thumbnail of Inflammatory Bowel Disease: The Association of Inflammatory Cytokine Gene Polymorphisms

New Insights into Inflammatory Bowel Disease, 2016

The frequencies of alleles and genotypes of TNF-α, TNF-β, and IL-10 genes were examined in Saudi ... more The frequencies of alleles and genotypes of TNF-α, TNF-β, and IL-10 genes were examined in Saudi subjects including IBD patients (UC and CD) and matched controls. Venous blood samples were collected from IBD patients and healthy control subjects, and genomic DNA was extracted using commercially available kit (Qiagen, CA, USA). In order to detect TNF-α (-308G/A), TNF-β (+252A/G), IL-10 (-1082G/A), (-819C/T), and (-592C/A) polymorphisms, the TNF-α, TNF-β, and IL-10 genes were amplified using an amplification refractory mutation systems PCR methodology. Analysis of data showed that the frequencies of alleles and genotype of TNF-α (-308G/A), TNF-β (+252A/G), and IL-10 (-1082G/A), (-819C/T), and (-592C/A) polymorphisms differ between IBD patients and control subjects. Our study clearly indicated that the TNF-α (-308G/A), TNF-β (+252A/G), and IL-10 (-1082 G/A) polymorphisms are associated significantly with the risk of IBD susceptibility while other two, IL-10-819C/T and IL-10-592C/A, polymorphisms are not associated with IBD in Saudi population. However, well-designed epidemiological as well as genetic association studies with large sample size among different ethnicities should be performed in order to have better understanding of this relationship.

Research paper thumbnail of Stabilization of eggshell in Heteromicrocotyle indicus Ramalingam, 1960 (Monogenea : Microcotylidae)

Research paper thumbnail of Histocompatibility antigens in Saudi patients with Vitiligo

Research paper thumbnail of Chemical Nature and Mode of Stabilization of Egg-shell in Helicometra pulchella (Rudolphi, 1819) (Digenea: Opecoelidae)

Acta Zoologica, 1992

The chemical nature and mode of stabilization of the eggshell/capsule of Moniezia expansa, Avitet... more The chemical nature and mode of stabilization of the eggshell/capsule of Moniezia expansa, Avitetlina lahorea and Stilesia globipunctata have been investigated using histochemical techniques. In M. expansa where viteliine glands are present, the eggshell is stabilized by-S-S and-S-H linkages whereas in A. lahorea and S. globipunctata, the viteliine glands are absent and the double membranes, fibrous capsule and paruterine organ contain mainly elastokeratin-type structural protein. The possible role of the vitellaria in the presence or absence of eggshell and its thickness is discussed.

Research paper thumbnail of Vol. 49 No. 4/2002 1013–1017 QUARTERLY Communication

Molecular cloning and sequencing of rabbit presenilin-1 cDNA fragment ��

Research paper thumbnail of Histochemical Studies on the Egg-shell Formation of Some Helminth Parasites

Research paper thumbnail of Histochemical Nature and Mode of Stabilization of Skeletal Structures in some Trematodes

Zoologischer Anzeiger a Journal of Comparative Zoology, 1991

Research paper thumbnail of Histochemical Nature and Mode of Stabilization of Skeletal Structures in some Trematodes

Zoologischer Anzeiger - A Journal of Comparative Zoology

Research paper thumbnail of Seasonal Incidence and Pathogenicity of the metacercariae of Clinostomum complanatum in Aphanius dispar

Parasitology International

Research paper thumbnail of Association of Functional Polymorphism in Protein Tyrosine Phosphatase Nonreceptor 22 (PTPN22) Gene with Vitiligo

Biomarker Insights, 2020

The protein tyrosine phosphatase nonreceptor 22 (PTPN22) is associated with susceptibility to aut... more The protein tyrosine phosphatase nonreceptor 22 (PTPN22) is associated with susceptibility to autoimmune diseases. The functional polymorphism in PTPN22 at 1857 is a strong risk factor for vitiligo susceptibility in Europeans; however, controversy exits in other populations. Present study was aimed to determine whether the PTPN22 C1857T polymorphism confers susceptibility to vitiligo in Saudi Arabians. Genomic DNA was extracted and amplified using tetra primer amplification-refractory mutation system polymerase chain reaction (ARMS-PCR) method. The frequencies of allele T and genotype CT of PTPN22 C1858T polymorphism were significantly higher, whereas those of allele C and genotype CC were lower in patients as compared with controls (P < 0.0001). The genotype TT was absent in both the patients and controls. It is concluded that PTPN22 C1858T polymorphism is strongly associated with vitiligo susceptibility. However, additional studies are warranted using large number of samples from different ethnicities and geographical areas.

Research paper thumbnail of Association of tumor necrosis factor-&alpha; and -&beta; gene polymorphisms in inflammatory bowel disease

Journal of Inflammation Research, Jun 1, 2016

Inflammatory bowel disease (IBD) is a complex, multifactorial, chronic inflammatory disorder of t... more Inflammatory bowel disease (IBD) is a complex, multifactorial, chronic inflammatory disorder of the gastrointestinal tract in which immune dysregulation caused by genetic and/or environmental factors plays an important role. The aim of this casecontrol study was to evaluate the association of tumor necrosis factor-alpha (TNF-α) (308) and-β (+252) polymorphisms with susceptibility of IBD. A total of 379 Saudi subjects including 179 IBD patients (ulcerative colitis (UC) =84 and Crohn's disease (CD) =95) and 200 age-and sex-matched healthy controls were recruited. TNF-a and TNF-b genes were amplified using an amplification refractory mutation systems polymerase chain reaction methodology to detect TNF-α (-308) and-β (+252) polymorphisms. The frequency of the GA genotype of TNF-α (-308G/A) was higher, and the frequencies of the GG and AA genotypes were significantly lower in IBD patients compared with those in controls, indicating that genotype GA-positive individuals are susceptible to IBD and that the GG and AA genotypes exert a protective effect. The frequency of allele A of TNF-α (-308G/A) was significantly higher and that of allele G was lower in IBD patients compared with those in controls, indicating an association of allele A with IBD risk in Saudi patients. On stratification of IBD patients into UC and CD, an almost similar pattern was noticed in both the groups. The results of TNF-β (+252A/G) polymorphisms showed a significant increase in the frequency of the GG genotype in IBD patients, suggesting a positive association of GG genotype with IBD risk. On stratification of IBD patients into UC and CD, the genotype GG of TNF-β was associated with susceptibility risk to UC but not CD. The frequencies of alleles and genotypes of both TNF-α and-β polymorphisms are not affected by sex or type of IBD (familial or sporadic). TNF-α (-308G/A) and TNF-β (+252A/G) polymorphisms are associated with risk of developing IBD in Saudi population.

Research paper thumbnail of Association of Interleukin-10 Gene Promoter Polymorphisms in Saudi Patients with Vitiligo

Disease Markers, 2008

The promoter region of human Interleukin-10 gene is highly polymorphic and has been associated wi... more The promoter region of human Interleukin-10 gene is highly polymorphic and has been associated with numerous autoimmune diseases. Recent studies have linked vitiligo with defective autoimmune system. This study is aimed to explore a possible association between IL-10 gene polymorphism and vitiligo in Saudi population. This case control study consisted of 184 Saudi subjects including 83 vitiligo patients (40 males, 43 females mean age 27.85 ± 12.43 years) and 101 matched controls. Genomic DNA was extracted from the blood samples of healthy controls and Vitiligo patients visiting out patient clinic of Department of Dermatology, Riyadh Armed Forces Hospital, using QIA amp R DNA mini kit (Qiagen CA, USA). Interleukin-10 gene was amplified by polymerase chain reaction (PCR) using Arms primers to detect any polymorphism involved at positions −592, −819 and −1082. The frequencies of GG genotype at −1082, and CC genotype at positions −592 and 819 were significantly higher in vitiligo patients compared to healthy subjects suggesting that GG and CC genotypes might be susceptible to vitiligo in Saudis. On the other hand genotypes −1082 GA, −819 CT, and −592 CA of IL-10 were more prevalent in healthy controls suggesting protective effects of GA, CT and CA genotypes against vitiligo. This study indicates that the IL-10 gene may play a significant role in the etiology of vitiligo among Saudis.

Research paper thumbnail of Association of genetic polymorphisms in interferon-γ, interleukin-6 and transforming growth factor-β1 gene with oral lichen planus susceptibility

BMC Oral Health, Aug 20, 2016

Background: Oral lichen planus (OLP) is a premalignant mucocutaneous disease in which genetic fac... more Background: Oral lichen planus (OLP) is a premalignant mucocutaneous disease in which genetic factors and immune responses play a major role. Cytokines play an important role in the pathogenesis and disease progression of OLP. The aim of this study was to investigate the impact of gene polymorphisms of T helper cell subtype Th1 and Th2 cytokines, interferon-gamma (IFN-γ), interleukin-6 (IL-6) and transforming growth factor (TGF)-β1 on OLP susceptibility in a Saudi cohort. Methods: Forty two unrelated patients with OLP and 195 healthy controls were genotyped for IFN-γ (874A/T), IL-6 (174G/C) and TGF-β1 (509C/T) polymorphisms. Results: The frequency of genotype AT of IFN-γ (874A/T) was significantly higher while genotype AA was lower in OLP patients as compared to controls (P < 0.05). The frequency of T containing genotypes (AT + TT) was also higher in OLP patients as compared to that in controls (P = 0.003). The frequencies of allele T was higher while that of allele A lower in patients than the controls however the difference was not statistically significant (P = 0.07). There was no significant difference in the frequencies of alleles and genotypes of IL-6 (174G/C) and TGF-β1 (509C/T) polymorphisms between patient and control groups. These results indicated that genotype AT of IFN-γ (874A/T) polymorphism is associated with OLP risk and genotype AA is protective to OLP. On the other hand the polymorphisms IL-6 (174G/C) and TGF-β1 (509C/T) may not be associated with OLP risk in our population. Conclusion: It is concluded that IFN-γ (874A/T) polymorphism is associated with the susceptibility of OLP, however further studies with large sample size involving different ethnic populations should be conducted to strengthen our results.

Research paper thumbnail of Systemic lupus erythematosus and infections: a retrospective study in Saudis

Lupus, Sep 1, 2007

This study demonstrates demographic, clinical and laboratory characteristics with special referen... more This study demonstrates demographic, clinical and laboratory characteristics with special reference to infections in Saudi patients with SLE. One-hundred and ninety-nine patients with SLE treated at Riyadh Armed Forces Hospital, Saudi Arabia over a period of 15 years (1990-2005) were retrospectively reviewed. There were 162 females and 37 males (4.4 : 1) with an average age of 35 years at onset of disease. Duration of diseases ranged from one to 23 years with a mean of 7.23 years. Some of the clinical characteristics of SLE patients observed were nephritis (53.7%), fever (53.26%), neuropsychological disorder (36.18%), malar/butterfly rash (27.6%), pulmonary disorder (22.6%), photosensitivity (21.6%), cardiac involvement (21.1%) and oral ulcers (19.09%). Infection was the major complication with 58.79% of SLE patient having suffered from various infections. A total of 22 species of pathogens including gram positive and gram negative bacteria, viruses and fungi were isolated from 117 SLE patients. Single to multiple episode of infection with various pathogens were recorded however, majority of patients harboured one or two species of pathogens. Bacterial infection was predominant (78.6%) followed by viral (28.2%) and fungal (28.2%) infections. Forty-four percent of SLE patients were found to be infected with organisms classified as opportunistic. The high incidence of infections in SLE patients may be attributed to the multiple intrinsic and extrinsic risk factors including deficiency of complement (C3 and C4), disease activity, renal impairment, use of glucocorticoid and cytotoxic drugs. It is concluded that more judicious use of corticosteroids and other immunosuppressive agents will be critical to limit the infections in SLE and a high alert and close monitoring of patients will ensure optimal patient outcome, both in terms of morbidity and mortality.

Research paper thumbnail of Association of tumor necrosis factor-α and -β gene polymorphisms in inflammatory bowel disease

Research paper thumbnail of Larval digenea of Melanoides tuberculatus (Muller,1774) (Gastropoda: Prosobranchia) from Al-Hassa province, Saudi Arabia

Research paper thumbnail of Occurrence of larval Philophthalmus gralli (Mathis and Leger, 1910) in freshwater snail Melanoides tuberculatus (Muller) from Al-Hafuf, Saudi Arabia and its development into adult in various experimental hosts

Parasitology International, 1997

This is the first report of occurrence of Philophthalmus gralli in Melanoides tuberculatus from S... more This is the first report of occurrence of Philophthalmus gralli in Melanoides tuberculatus from Saudi Arabia. The overall infection rate of M. tuberculatus with P. gralli larvae was 8.9%. However, the incidence of infection varied from 6.46 to 10.16% depending on the size of the snail, and larger snails were found to be more infected than the smaller ones. The emerging cercariae encysted on the surface of water which were excysted in vitro and inoculated in the eyes of various experimental hosts. Metacercariae transformed into mature adults in the eyes of chicken, pigeons and quails but failed to develop in mice and rabbits. There was rapid growth in size up to 30 days post-infection (Pi). First egg appeared 13 days Pi, but mature worms having eggs containing fully developed miracidium were obtained 30 days Pi. P. gralli which developed in chicken, pigeons and quails were not uniform in body dimensions, especially those of gonads, indicating the effects of host on development. Moreover, development was found to be retarded in crowded conditions. Migration of worms from one eye to the other occurred in 25% of infections.

Research paper thumbnail of In vitro Excystation of Metacercariae of Clinostomum complanatum (Rudolphi, 1819) (Digenea: Clinostomatidae)

Acta Zoologica, 1988

ABSTRACT In vitro excystation of metacercariae of Clinostomum complanatum (Rudolphi, 1819) was st... more ABSTRACT In vitro excystation of metacercariae of Clinostomum complanatum (Rudolphi, 1819) was studied. Excystation was an active process, initiated by a rise in temperature. The metacercariae excysted in enzymic as well as non enzymic medium, but the rate of excystation was affected by the temperature and/or pH of the medium. The optimal excystation was obtained in pepsin-Tyrode at pH 2.3-3.5 and a temperature of 42°C. Trypsin treatment was not required.

Research paper thumbnail of Apolipoprotein E polymorphisms and primary glaucoma in Saudis

Molecular vision, 2009

The frequencies of apolipoprotein E (APOE) alleles and genotypes were examined in 230 Saudi subje... more The frequencies of apolipoprotein E (APOE) alleles and genotypes were examined in 230 Saudi subjects including primary open-angle glaucoma (POAG; n=60) and primary angle-closure glaucoma (PACG; n=40) patients as well as 130 control subjects. The presence of glaucoma in patients was based on clinical examination and/or ophthalmic records. The APOE allele frequency (epsilon2, epsilon3, and epsilon4) was studied by polymerase chain reaction (PCR) followed by reverse-hybridization and restriction fragment length polymorphism techniques. Analysis of data showed a complete absence of epsilon2 allele and a significantly lower frequency of the epsilon3 allele in primary glaucoma patients (90.5%) compared to the control subjects (95.7%, p=0.034, relative risk [RR]=0.473, protective fraction [PF]=0.318). The frequency of the epsilon4 allele was significantly higher in the glaucoma patients (9.5%) compared to the control subjects (4.2%, p=0.034, RR=2.169, etiological fraction [EF]=0.329). The ...

Research paper thumbnail of Association of TNF-α and TNF-β Gene Polymorphisms with Primary Open Angle and Primary Angle Closure Glaucoma

Research paper thumbnail of Inflammatory Bowel Disease: The Association of Inflammatory Cytokine Gene Polymorphisms

New Insights into Inflammatory Bowel Disease, 2016

The frequencies of alleles and genotypes of TNF-α, TNF-β, and IL-10 genes were examined in Saudi ... more The frequencies of alleles and genotypes of TNF-α, TNF-β, and IL-10 genes were examined in Saudi subjects including IBD patients (UC and CD) and matched controls. Venous blood samples were collected from IBD patients and healthy control subjects, and genomic DNA was extracted using commercially available kit (Qiagen, CA, USA). In order to detect TNF-α (-308G/A), TNF-β (+252A/G), IL-10 (-1082G/A), (-819C/T), and (-592C/A) polymorphisms, the TNF-α, TNF-β, and IL-10 genes were amplified using an amplification refractory mutation systems PCR methodology. Analysis of data showed that the frequencies of alleles and genotype of TNF-α (-308G/A), TNF-β (+252A/G), and IL-10 (-1082G/A), (-819C/T), and (-592C/A) polymorphisms differ between IBD patients and control subjects. Our study clearly indicated that the TNF-α (-308G/A), TNF-β (+252A/G), and IL-10 (-1082 G/A) polymorphisms are associated significantly with the risk of IBD susceptibility while other two, IL-10-819C/T and IL-10-592C/A, polymorphisms are not associated with IBD in Saudi population. However, well-designed epidemiological as well as genetic association studies with large sample size among different ethnicities should be performed in order to have better understanding of this relationship.

Research paper thumbnail of Stabilization of eggshell in Heteromicrocotyle indicus Ramalingam, 1960 (Monogenea : Microcotylidae)

Research paper thumbnail of Histocompatibility antigens in Saudi patients with Vitiligo

Research paper thumbnail of Chemical Nature and Mode of Stabilization of Egg-shell in Helicometra pulchella (Rudolphi, 1819) (Digenea: Opecoelidae)

Acta Zoologica, 1992

The chemical nature and mode of stabilization of the eggshell/capsule of Moniezia expansa, Avitet... more The chemical nature and mode of stabilization of the eggshell/capsule of Moniezia expansa, Avitetlina lahorea and Stilesia globipunctata have been investigated using histochemical techniques. In M. expansa where viteliine glands are present, the eggshell is stabilized by-S-S and-S-H linkages whereas in A. lahorea and S. globipunctata, the viteliine glands are absent and the double membranes, fibrous capsule and paruterine organ contain mainly elastokeratin-type structural protein. The possible role of the vitellaria in the presence or absence of eggshell and its thickness is discussed.

Research paper thumbnail of Vol. 49 No. 4/2002 1013–1017 QUARTERLY Communication

Molecular cloning and sequencing of rabbit presenilin-1 cDNA fragment ��

Research paper thumbnail of Histochemical Studies on the Egg-shell Formation of Some Helminth Parasites

Research paper thumbnail of Histochemical Nature and Mode of Stabilization of Skeletal Structures in some Trematodes

Zoologischer Anzeiger a Journal of Comparative Zoology, 1991

Research paper thumbnail of Histochemical Nature and Mode of Stabilization of Skeletal Structures in some Trematodes

Zoologischer Anzeiger - A Journal of Comparative Zoology

Research paper thumbnail of Seasonal Incidence and Pathogenicity of the metacercariae of Clinostomum complanatum in Aphanius dispar

Parasitology International