John Briggs - Academia.edu (original) (raw)
Papers by John Briggs
Antimicrobial Agents and Chemotherapy, Apr 1, 2012
The emergence of drug resistance threatens to limit the use of current anti-HIV-1 drugs and highl... more The emergence of drug resistance threatens to limit the use of current anti-HIV-1 drugs and highlights the need to expand the number of treatment options available for HIV-1-infected individuals. Our previous studies demonstrated that two clinically approved drugs, decitabine and gemcitabine, potently inhibited HIV-1 replication in cell culture through a mechanism that is distinct from the mechanisms for the drugs currently used to treat HIV-1 infection. We further demonstrated that gemcitabine inhibited replication of a related retrovirus, murine leukemia virus (MuLV), in vivo using the MuLV-based LP-BM5/murine AIDS (MAIDS) mouse model at doses that were not toxic. Since decitabine and gemcitabine inhibited MuLV and HIV-1 replication with similar potency in cell culture, the current study examined the efficacy and toxicity of the drug combination using the MAIDS model. The data demonstrate that the drug combination inhibited disease progression, as detected by histopathology, viral loads, and spleen weights, at doses lower than those that would be required if the drugs were used individually. The combination of decitabine and gemcitabine exerted antiviral activity at doses that were not toxic. These findings indicate that the combination of decitabine and gemcitabine shows potent antiretroviral activity at nontoxic doses and should be further investigated for clinical relevance.
Journal of Invertebrate Pathology, 1984
Sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) can provide information to... more Sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) can provide information to identify microsporidia infecting invertebrate species of agricultural and medical importance (D. A.
Toxicology Letters, May 1, 2017
Cyanide is a metabolic poison that inhibits cytochrome c oxidase. Its broad applications in manuf... more Cyanide is a metabolic poison that inhibits cytochrome c oxidase. Its broad applications in manufacturing and history as an agent of warfare/terror highlight the limitations in approved cyanide antidotes for mass casualties. Sulfanegen, a pre-clinical antidote for cyanide poisoning, exploits an endogenous detoxification pathway and should be amenable to mass-casualty scenarios. Because human studies are unethical, determination of appropriate animal species as models in translational studies for FDA approval under the "Animal Rule" are critical. Here, we compared the specific activities of mercaptopyruvate sulfurtransferase (MST, required for sulfanegen's activity), across common laboratory models of cyanide intoxication, and humans. Human MST activities in erythrocytes (measured as micromole pyruvate/min/10 6 rbc) were closest to those of Swiss-Webster mice and NZW rabbits. Similar species were selected for a more detailed tissue-specific comparison of MST activities. NZW Rabbits were closest to humans in the liver and kidney mitochondrial fractions, the Swiss-Webster mouse was closest to humans in the liver cytosolic fraction, while C57BL/6 mouse was closest in the kidney cytosolic fraction. These data comparing MST activities in animal models will help justify the use of those specific animals per the animal rule. Interestingly, statistically significant differences were found in MST activities of liver mitochondria between human smokers and non-smokers (p= 0.0030).
Medical science educator, Sep 1, 2013
ABSTRACT Our institution uses a model of group testing in which students retake exam questions in... more ABSTRACT Our institution uses a model of group testing in which students retake exam questions in a group after submitting individual answers. We examined the effects of group testing on exam performance and group dynamics. Students scored higher after discussing the questions. When the same cohort of students was allowed to submit an independent answer one year and then required to achieve consensus the next, the improvement in their performance after discussion did not change. 83.1% of students reported teaching during the group exam. 65.1% reported groups achieve unanimity "often"; 56.4% reported feeling pressured by peers. While in pre-formed groups, personal stress was decreased in 44% of respondents and there was less conflict in 60% of respondents compared to randomly formed groups. Hostility was three times more likely in a random group than a pre-formed group (37% vs. 12%). Both teaching and seeking clarification occurred more often in pre-formed groups. These data suggest that group testing can be used to enhance student performance, understanding, and retention. However some students feel pressured and find these groups to be hostile environments. Testing within a pre-formed group may provide students with an opportunity to teach each other with decreased stress and anxiety.
American Journal of Physiology-regulatory Integrative and Comparative Physiology, Aug 1, 1998
Inhibition of a signal that produces positive energy balance involving neuropeptide Y (NPY) proje... more Inhibition of a signal that produces positive energy balance involving neuropeptide Y (NPY) projection from arcuate nucleus (Arc; site of NPY synthesis) to paraventricular nucleus (PVN; site of NPY release) is one potential mechanism of leptin action. NPY in the PVN increases feeding and decreases uncoupling protein (UCP) activity in brown fat, whereas leptin decreases NPY biosynthesis in the Arc, which presumably decreases PVN NPY. It is hypothesized that decreased NPY activity is necessary for the satiety and thermogenic effects of leptin. To test this, we first determined the effect of leptin on feeding in two paradigms: satiated rats and food-deprived rats. Leptin was effective in decreasing feeding in the satiated rats but ineffective in the food-deprived rats. Next, we determined that leptin decreases NPY and increases UCP gene expression. Finally, we injected leptin intracerebroventricularly before specific PVN NPY microinjection. We found that repletion of NPY in PVN by specific NPY microinjection reverses the feeding-inhibitory and thermogenic effects of centrally administered leptin, the first functional evidence indicating that leptin acts on the Arc-PVN feeding-regulatory pathway.
American Journal of Physiology-regulatory Integrative and Comparative Physiology, Aug 1, 1998
Neuropeptide Y (NPY) injected into the paraventricular nucleus (PVN) increases feeding and decrea... more Neuropeptide Y (NPY) injected into the paraventricular nucleus (PVN) increases feeding and decreases brown adipose tissue (BAT) uncoupling protein (UCP) and lipoprotein lipase (LPL) mRNA. Previously we reported that the feeding and BAT effects induced by NPY in the PVN are blocked by 50 µg naltrexone (NTX) in the rostral nucleus of the solitary tract (rNTS). We sought to determine whether the effect of rNTS NTX on PVN NPY-induced alterations in energy metabolism occurred at lower doses of NTX. Male Sprague-Dawley rats were fitted with cannulas into two sites: PVN and rNTS. Feeding response, BAT UCP, and LPL mRNA were measured after injection of 0, 5, 10, and 25 µg NTX in the rNTS Ϯ 1 µg NPY in the PVN. One-hour feeding response to PVN NPY was significantly and dose dependently decreased by 10 and 25 µg rNTS NTX (Ϫ23 and Ϫ31%, respectively). However, rNTS NTX did not block the PVN NPY-induced decrease in BAT UCP or LPL mRNA. BAT -actin mRNA (as a measure of overall changes in gene expression) was unchanged among treatment groups. These results indicate a possible divergence in the PVN NPY feeding-stimulatory/BAT-inhibitory pathway, such that PVN NPY feeding effects may be routed through the rNTS whereas BAT effects may be due to alterations at another neural site.
American Journal of Physiology-regulatory Integrative and Comparative Physiology, Feb 1, 2000
Neuropeptide Y (NPY) injected into the hypothalamic paraventricular nucleus (PVN) stimulates feed... more Neuropeptide Y (NPY) injected into the hypothalamic paraventricular nucleus (PVN) stimulates feeding and decreases uncoupling protein (UCP)-1 mRNA in brown adipose tissue (BAT). The present studies were undertaken to determine whether UCP-2 in white adipose tissue (WAT) and UCP-3 in muscle are regulated by NPY in the PVN. PVN-cannulated male Sprague-Dawley rats were injected with either saline or NPY (PVN, 117 pmol, 0.5 µl) every 6 h for 24 h. NPY in the PVN stimulated feeding and decreased UCP-1 mRNA in BAT independent of NPY-induced feeding. UCP-2 mRNA in WAT was unchanged by NPY. In acromiotrapezius muscle, NPY decreased UCP-3 mRNA, but this was reversed by restricting food intake to control levels. In biceps femoris muscle, NPY alone had no effect on UCP-3 mRNA, but UCP-3 mRNA was significantly increased in the NPY-treated rats that were restricted to control levels of intake. These results suggest that UCP-2 in WAT and UCP-3 in muscle are not subject to specific regulation by NPY in the PVN.
Minnesota medicine, Apr 1, 1949
European journal of endocrinology, Mar 1, 1977
Since growth hormone (GH) and prolactin (Prl) secretion by human pituitary tumours is often influ... more Since growth hormone (GH) and prolactin (Prl) secretion by human pituitary tumours is often influenced by the hypophysiotrophic hormones thyrotrophin-releasing hormone (TRH) and somatostatin (SRIF), we have examined the responses of several transplantable rat pituitary tumours to these substances in a perifusion apparatus. The MStT/W15 tumour did not alter its secretion of GH and Prl in response to TRH, SRIF, or a partially purified porcine hypothalamic extract containing GH-releasing activity; normal rat pituitaries show clear responses to each of these substances. Theophylline and dibutyryl cyclic AMP each provoked increased GH and Prl release from the tumour. A second specimen of the
Journal of Youth Studies, Dec 1, 2008
Biochemical and Biophysical Research Communications, Sep 1, 1980
Vol. 96, No. 1, 1980 BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS September 16, 1980 Pages... more Vol. 96, No. 1, 1980 BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS September 16, 1980 Pages 4753 A PROLACTIN INHIBITORY FACTOR WITH IMMUNOCHARACTERISTICS SIMILAR TO THYROTROPIN RELEASING FACTOR (TRH) IS PRESENT IN RAT ...
American Journal of Physiology-regulatory Integrative and Comparative Physiology, Feb 1, 1991
Endocrinology, Sep 1, 1980
ABSTRACT
Physiology & Behavior, Jun 1, 2003
The early changes in the central nervous system (CNS) following drinking of ethanol (ETOH) are po... more The early changes in the central nervous system (CNS) following drinking of ethanol (ETOH) are poorly understood. It is known that chronic intracerebroventricular (ICV) administration of ethanol to rats induces preference for imbibed alcohol solutions. These results suggest that ICV ethanol could alter taste preference. In the present study, we tested whether ETOH{ICV} could induce a conditioned taste preference (CTP) or aversion (CTA) and alter c-Fos immunoreactivity (c-Fos-IR) in brain regions associated with feeding, aversion, and/or reward. Acute ETOH{ICV}, as tested in the ETOH-naïve rat, did not induce CTA nor affect the amount of water imbibed by treated rats. The effects of ETOH{ICV} on intake and preference were determined using a novel palatable (i.e. sweet) noncaloric 0.1% saccharin solution. A single dose of ETOH{ICV} in the ETOH-naïve animal induced a CTP for saccharin. ETOH{ICV} significantly increased c-Fos-IR in a number of brain sites associated with feeding and reward including the bed nucleus of the stria terminalis, lateral dorsal area (BSTLD); nucleus accumbens, shell area (AcbSh); hypothalamic paraventricular nucleus (PVN); and lateral septum, ventral area (LSV). Thus, ETOH induced a CTP, not CTA, via central mechanisms; it increased c-Fos-IR in specific sites associated with feeding and reward.
Hormone research, 1980
Cultured GH3 rat pituitary tumor cells which secrete prolactin (PRL) were used to study autoregul... more Cultured GH3 rat pituitary tumor cells which secrete prolactin (PRL) were used to study autoregulation of rat PRL (rPRL) secretion. Acute (1 h) release of rPRL by cells in monolayer culture was inhibited by ovine PRL (oPRL; 10(-7) and 10(-8) M). Intracellular rPRL accumulation was not inhibited by exogenous oPRL. No effect of oPRL was seen during long-term (12-day) incubation of cells with oPRL (10(-7) to 10(-9) M). oPRL exerts an acute suppressive effect on rPRL release at the cellular level, but does not inhibit rPRL synthesis or long-term release.
Copeia, Feb 20, 1979
... than freshwater pathways, ostar-iophysan fishes [meaning those groups of or-ders and families... more ... than freshwater pathways, ostar-iophysan fishes [meaning those groups of or-ders and families characterized by the posses-sion of a Weberian apparatus for the transmission of sound impulses from the swim bladder to the inner ear = the Otophysi of Ro-sen and Greenwood ...
Journal of Biogeography, Jul 1, 1999
Summary Aim To provide evidence suggesting the existence of a dynamic system of extinction and re... more Summary Aim To provide evidence suggesting the existence of a dynamic system of extinction and replacement. Location The Indo‐West Pacific Ocean. Methods Utilization of species distribution patterns produced by detailed systematic works. Results The distribution patterns appear to suggest a sequence of events that is consistent with the centre of origin hypothesis. The East Indies centre is considered to operate according to the centrifugal speciation model. Main conclusions Disjunct patterns appear to have originated in the East Indies and spread out from there. In cases where the vacated area is occupied by a sibling species, competitive (sympatric) speciation may have occurred. Over time the extinction pattern will gradually extend outward until it is played out among small populations far from their centre of origin
Brain Research, Aug 1, 1981
The administration of morphine to rats at room temperature is reported to suppress serum thyrotro... more The administration of morphine to rats at room temperature is reported to suppress serum thyrotropin (TSH) levels by a hypothalamic mechanism. However, it is unknown whether endogenous opioid peptides (EOP) are involved in the control of TSH secretion. The present studies show that naloxone (10 mg/kg, i.p.), an opiatereceptor antagonist, prevented the decline in rat serum TSH which occurs with heat exposure. Morphine sulfate (20 mg/kg, i.p.) treatment prevented the cold-induced elevation in serum TSH, and pretreatment with haloperidol (0.3 mg/kg, i.p.) eliminated morphine's influence. Medial-basal hypothalamic thyrotropin-releasing hormone (TRH) content, measured by RIA, increased in the morphine-treated rats which were exposed to 4 °C. A submaximal intravenous dose of TRH (300 ng/100 g) was given to determine whether morphine suppresses serum TSH through the release of hypothalamic thyrotropic inhibitors. Morphine pretreatment did not alter TSH stimulation by TRH. Morphine alone or combined with TRH did not alter basal or stimulated TSH secretion in vitro. These studies strongly suggest that, in rats, the EOP modulate TSH secretion under conditions such as acute heat exposure which are associated with a decline in serum TSH. Under specific circumstances, the suppression of serum TSH by morphine may be dopamine-dependent.
Antimicrobial Agents and Chemotherapy, Apr 1, 2012
The emergence of drug resistance threatens to limit the use of current anti-HIV-1 drugs and highl... more The emergence of drug resistance threatens to limit the use of current anti-HIV-1 drugs and highlights the need to expand the number of treatment options available for HIV-1-infected individuals. Our previous studies demonstrated that two clinically approved drugs, decitabine and gemcitabine, potently inhibited HIV-1 replication in cell culture through a mechanism that is distinct from the mechanisms for the drugs currently used to treat HIV-1 infection. We further demonstrated that gemcitabine inhibited replication of a related retrovirus, murine leukemia virus (MuLV), in vivo using the MuLV-based LP-BM5/murine AIDS (MAIDS) mouse model at doses that were not toxic. Since decitabine and gemcitabine inhibited MuLV and HIV-1 replication with similar potency in cell culture, the current study examined the efficacy and toxicity of the drug combination using the MAIDS model. The data demonstrate that the drug combination inhibited disease progression, as detected by histopathology, viral loads, and spleen weights, at doses lower than those that would be required if the drugs were used individually. The combination of decitabine and gemcitabine exerted antiviral activity at doses that were not toxic. These findings indicate that the combination of decitabine and gemcitabine shows potent antiretroviral activity at nontoxic doses and should be further investigated for clinical relevance.
Journal of Invertebrate Pathology, 1984
Sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) can provide information to... more Sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) can provide information to identify microsporidia infecting invertebrate species of agricultural and medical importance (D. A.
Toxicology Letters, May 1, 2017
Cyanide is a metabolic poison that inhibits cytochrome c oxidase. Its broad applications in manuf... more Cyanide is a metabolic poison that inhibits cytochrome c oxidase. Its broad applications in manufacturing and history as an agent of warfare/terror highlight the limitations in approved cyanide antidotes for mass casualties. Sulfanegen, a pre-clinical antidote for cyanide poisoning, exploits an endogenous detoxification pathway and should be amenable to mass-casualty scenarios. Because human studies are unethical, determination of appropriate animal species as models in translational studies for FDA approval under the "Animal Rule" are critical. Here, we compared the specific activities of mercaptopyruvate sulfurtransferase (MST, required for sulfanegen's activity), across common laboratory models of cyanide intoxication, and humans. Human MST activities in erythrocytes (measured as micromole pyruvate/min/10 6 rbc) were closest to those of Swiss-Webster mice and NZW rabbits. Similar species were selected for a more detailed tissue-specific comparison of MST activities. NZW Rabbits were closest to humans in the liver and kidney mitochondrial fractions, the Swiss-Webster mouse was closest to humans in the liver cytosolic fraction, while C57BL/6 mouse was closest in the kidney cytosolic fraction. These data comparing MST activities in animal models will help justify the use of those specific animals per the animal rule. Interestingly, statistically significant differences were found in MST activities of liver mitochondria between human smokers and non-smokers (p= 0.0030).
Medical science educator, Sep 1, 2013
ABSTRACT Our institution uses a model of group testing in which students retake exam questions in... more ABSTRACT Our institution uses a model of group testing in which students retake exam questions in a group after submitting individual answers. We examined the effects of group testing on exam performance and group dynamics. Students scored higher after discussing the questions. When the same cohort of students was allowed to submit an independent answer one year and then required to achieve consensus the next, the improvement in their performance after discussion did not change. 83.1% of students reported teaching during the group exam. 65.1% reported groups achieve unanimity "often"; 56.4% reported feeling pressured by peers. While in pre-formed groups, personal stress was decreased in 44% of respondents and there was less conflict in 60% of respondents compared to randomly formed groups. Hostility was three times more likely in a random group than a pre-formed group (37% vs. 12%). Both teaching and seeking clarification occurred more often in pre-formed groups. These data suggest that group testing can be used to enhance student performance, understanding, and retention. However some students feel pressured and find these groups to be hostile environments. Testing within a pre-formed group may provide students with an opportunity to teach each other with decreased stress and anxiety.
American Journal of Physiology-regulatory Integrative and Comparative Physiology, Aug 1, 1998
Inhibition of a signal that produces positive energy balance involving neuropeptide Y (NPY) proje... more Inhibition of a signal that produces positive energy balance involving neuropeptide Y (NPY) projection from arcuate nucleus (Arc; site of NPY synthesis) to paraventricular nucleus (PVN; site of NPY release) is one potential mechanism of leptin action. NPY in the PVN increases feeding and decreases uncoupling protein (UCP) activity in brown fat, whereas leptin decreases NPY biosynthesis in the Arc, which presumably decreases PVN NPY. It is hypothesized that decreased NPY activity is necessary for the satiety and thermogenic effects of leptin. To test this, we first determined the effect of leptin on feeding in two paradigms: satiated rats and food-deprived rats. Leptin was effective in decreasing feeding in the satiated rats but ineffective in the food-deprived rats. Next, we determined that leptin decreases NPY and increases UCP gene expression. Finally, we injected leptin intracerebroventricularly before specific PVN NPY microinjection. We found that repletion of NPY in PVN by specific NPY microinjection reverses the feeding-inhibitory and thermogenic effects of centrally administered leptin, the first functional evidence indicating that leptin acts on the Arc-PVN feeding-regulatory pathway.
American Journal of Physiology-regulatory Integrative and Comparative Physiology, Aug 1, 1998
Neuropeptide Y (NPY) injected into the paraventricular nucleus (PVN) increases feeding and decrea... more Neuropeptide Y (NPY) injected into the paraventricular nucleus (PVN) increases feeding and decreases brown adipose tissue (BAT) uncoupling protein (UCP) and lipoprotein lipase (LPL) mRNA. Previously we reported that the feeding and BAT effects induced by NPY in the PVN are blocked by 50 µg naltrexone (NTX) in the rostral nucleus of the solitary tract (rNTS). We sought to determine whether the effect of rNTS NTX on PVN NPY-induced alterations in energy metabolism occurred at lower doses of NTX. Male Sprague-Dawley rats were fitted with cannulas into two sites: PVN and rNTS. Feeding response, BAT UCP, and LPL mRNA were measured after injection of 0, 5, 10, and 25 µg NTX in the rNTS Ϯ 1 µg NPY in the PVN. One-hour feeding response to PVN NPY was significantly and dose dependently decreased by 10 and 25 µg rNTS NTX (Ϫ23 and Ϫ31%, respectively). However, rNTS NTX did not block the PVN NPY-induced decrease in BAT UCP or LPL mRNA. BAT -actin mRNA (as a measure of overall changes in gene expression) was unchanged among treatment groups. These results indicate a possible divergence in the PVN NPY feeding-stimulatory/BAT-inhibitory pathway, such that PVN NPY feeding effects may be routed through the rNTS whereas BAT effects may be due to alterations at another neural site.
American Journal of Physiology-regulatory Integrative and Comparative Physiology, Feb 1, 2000
Neuropeptide Y (NPY) injected into the hypothalamic paraventricular nucleus (PVN) stimulates feed... more Neuropeptide Y (NPY) injected into the hypothalamic paraventricular nucleus (PVN) stimulates feeding and decreases uncoupling protein (UCP)-1 mRNA in brown adipose tissue (BAT). The present studies were undertaken to determine whether UCP-2 in white adipose tissue (WAT) and UCP-3 in muscle are regulated by NPY in the PVN. PVN-cannulated male Sprague-Dawley rats were injected with either saline or NPY (PVN, 117 pmol, 0.5 µl) every 6 h for 24 h. NPY in the PVN stimulated feeding and decreased UCP-1 mRNA in BAT independent of NPY-induced feeding. UCP-2 mRNA in WAT was unchanged by NPY. In acromiotrapezius muscle, NPY decreased UCP-3 mRNA, but this was reversed by restricting food intake to control levels. In biceps femoris muscle, NPY alone had no effect on UCP-3 mRNA, but UCP-3 mRNA was significantly increased in the NPY-treated rats that were restricted to control levels of intake. These results suggest that UCP-2 in WAT and UCP-3 in muscle are not subject to specific regulation by NPY in the PVN.
Minnesota medicine, Apr 1, 1949
European journal of endocrinology, Mar 1, 1977
Since growth hormone (GH) and prolactin (Prl) secretion by human pituitary tumours is often influ... more Since growth hormone (GH) and prolactin (Prl) secretion by human pituitary tumours is often influenced by the hypophysiotrophic hormones thyrotrophin-releasing hormone (TRH) and somatostatin (SRIF), we have examined the responses of several transplantable rat pituitary tumours to these substances in a perifusion apparatus. The MStT/W15 tumour did not alter its secretion of GH and Prl in response to TRH, SRIF, or a partially purified porcine hypothalamic extract containing GH-releasing activity; normal rat pituitaries show clear responses to each of these substances. Theophylline and dibutyryl cyclic AMP each provoked increased GH and Prl release from the tumour. A second specimen of the
Journal of Youth Studies, Dec 1, 2008
Biochemical and Biophysical Research Communications, Sep 1, 1980
Vol. 96, No. 1, 1980 BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS September 16, 1980 Pages... more Vol. 96, No. 1, 1980 BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS September 16, 1980 Pages 4753 A PROLACTIN INHIBITORY FACTOR WITH IMMUNOCHARACTERISTICS SIMILAR TO THYROTROPIN RELEASING FACTOR (TRH) IS PRESENT IN RAT ...
American Journal of Physiology-regulatory Integrative and Comparative Physiology, Feb 1, 1991
Endocrinology, Sep 1, 1980
ABSTRACT
Physiology & Behavior, Jun 1, 2003
The early changes in the central nervous system (CNS) following drinking of ethanol (ETOH) are po... more The early changes in the central nervous system (CNS) following drinking of ethanol (ETOH) are poorly understood. It is known that chronic intracerebroventricular (ICV) administration of ethanol to rats induces preference for imbibed alcohol solutions. These results suggest that ICV ethanol could alter taste preference. In the present study, we tested whether ETOH{ICV} could induce a conditioned taste preference (CTP) or aversion (CTA) and alter c-Fos immunoreactivity (c-Fos-IR) in brain regions associated with feeding, aversion, and/or reward. Acute ETOH{ICV}, as tested in the ETOH-naïve rat, did not induce CTA nor affect the amount of water imbibed by treated rats. The effects of ETOH{ICV} on intake and preference were determined using a novel palatable (i.e. sweet) noncaloric 0.1% saccharin solution. A single dose of ETOH{ICV} in the ETOH-naïve animal induced a CTP for saccharin. ETOH{ICV} significantly increased c-Fos-IR in a number of brain sites associated with feeding and reward including the bed nucleus of the stria terminalis, lateral dorsal area (BSTLD); nucleus accumbens, shell area (AcbSh); hypothalamic paraventricular nucleus (PVN); and lateral septum, ventral area (LSV). Thus, ETOH induced a CTP, not CTA, via central mechanisms; it increased c-Fos-IR in specific sites associated with feeding and reward.
Hormone research, 1980
Cultured GH3 rat pituitary tumor cells which secrete prolactin (PRL) were used to study autoregul... more Cultured GH3 rat pituitary tumor cells which secrete prolactin (PRL) were used to study autoregulation of rat PRL (rPRL) secretion. Acute (1 h) release of rPRL by cells in monolayer culture was inhibited by ovine PRL (oPRL; 10(-7) and 10(-8) M). Intracellular rPRL accumulation was not inhibited by exogenous oPRL. No effect of oPRL was seen during long-term (12-day) incubation of cells with oPRL (10(-7) to 10(-9) M). oPRL exerts an acute suppressive effect on rPRL release at the cellular level, but does not inhibit rPRL synthesis or long-term release.
Copeia, Feb 20, 1979
... than freshwater pathways, ostar-iophysan fishes [meaning those groups of or-ders and families... more ... than freshwater pathways, ostar-iophysan fishes [meaning those groups of or-ders and families characterized by the posses-sion of a Weberian apparatus for the transmission of sound impulses from the swim bladder to the inner ear = the Otophysi of Ro-sen and Greenwood ...
Journal of Biogeography, Jul 1, 1999
Summary Aim To provide evidence suggesting the existence of a dynamic system of extinction and re... more Summary Aim To provide evidence suggesting the existence of a dynamic system of extinction and replacement. Location The Indo‐West Pacific Ocean. Methods Utilization of species distribution patterns produced by detailed systematic works. Results The distribution patterns appear to suggest a sequence of events that is consistent with the centre of origin hypothesis. The East Indies centre is considered to operate according to the centrifugal speciation model. Main conclusions Disjunct patterns appear to have originated in the East Indies and spread out from there. In cases where the vacated area is occupied by a sibling species, competitive (sympatric) speciation may have occurred. Over time the extinction pattern will gradually extend outward until it is played out among small populations far from their centre of origin
Brain Research, Aug 1, 1981
The administration of morphine to rats at room temperature is reported to suppress serum thyrotro... more The administration of morphine to rats at room temperature is reported to suppress serum thyrotropin (TSH) levels by a hypothalamic mechanism. However, it is unknown whether endogenous opioid peptides (EOP) are involved in the control of TSH secretion. The present studies show that naloxone (10 mg/kg, i.p.), an opiatereceptor antagonist, prevented the decline in rat serum TSH which occurs with heat exposure. Morphine sulfate (20 mg/kg, i.p.) treatment prevented the cold-induced elevation in serum TSH, and pretreatment with haloperidol (0.3 mg/kg, i.p.) eliminated morphine's influence. Medial-basal hypothalamic thyrotropin-releasing hormone (TRH) content, measured by RIA, increased in the morphine-treated rats which were exposed to 4 °C. A submaximal intravenous dose of TRH (300 ng/100 g) was given to determine whether morphine suppresses serum TSH through the release of hypothalamic thyrotropic inhibitors. Morphine pretreatment did not alter TSH stimulation by TRH. Morphine alone or combined with TRH did not alter basal or stimulated TSH secretion in vitro. These studies strongly suggest that, in rats, the EOP modulate TSH secretion under conditions such as acute heat exposure which are associated with a decline in serum TSH. Under specific circumstances, the suppression of serum TSH by morphine may be dopamine-dependent.