INTEREST IN FAMILY MEDICINE SPECIALIZATION AMONG MEDICAL UNDERGRADUATES OF THE UNIVERSITY OF IBADAN, NIGERIA.

BACKGROUND: One of the strategies adopted to improve interest in family medicine (FM) by many regions was the introduction of undergraduate family medicine training into the Medical School Curriculum. However, medical students' interest in FM has been reportedly low ranging from 3 - 29%. OBJECTIVES: This study described the pattern of medical students' specialty choices and assessed factors associated with interest in FM specialization among them. METHODS: Using a cross-sectional study design, total sampling of fourth to sixth-year medical students undergoing family medicine rotation as of November 2017 (N= 412) was done. The response rate was 75% (N=309). A pre-validated semi-structured, self-administered questionnaire was utilized to assess factors associated with respondents' interest in 12 medical specialties including FM. RESULTS: The respondents were predominantly male (67.3%), with a mean age of 23 (± 7.9) years. Most (83.4%) of them had at least one parent with tertiary school education. Fifteen (4.9%) of the respondents indicated a current interest in specializing in FM while 112 (36.2%) would consider FM in the future. A higher proportion of those with family members with FM specialization (28.6%) expressed current interest in FM while the female gender was associated with future consideration of FM. CONCLUSION: There is a low interest in FM specialization among medical students and this may be attributable to the fact that FM undergraduate training is relatively new in Nigeria. Further research on the role of mentorship and preceptorship on specialty choices of medical students needs to be carried out.

Age related Histology and Immunohistochemistry of some intermediate filaments in the Testis of the African Catfish (Clarias gariepinus).

The African Catfish (Clarias gariepinus) are important source of protein for local consumers in developing countries in Africa and have also been reported to have enormous commercial potential. Several works have been done on plethora of general histological, biochemical and hormone changes which accompany puberty in African Catfish. Other studies have touched the effects of ecotoxins on the histological and reproductive parameters of the mature African Catfish. This study is an attempt to use immunohistochemical and basic histology to elucidate the baseline information on the general structural differences between the testes of immature and post-pubertal catfish with respect to some intermediate filaments arrangement within the testicular tissue. Ten (10) each of mature male catfish (4-5 months old) and immature male catfish (3 months old) were used in the study. The fish were subjected to cold shock and decapitated before the testes were harvested from both groups. These tissues were fixed in Bouins fluid for 24 hours and subsequently transferred into 70% Ethanol. Testicular tissues from both groups were processed for paraffin embedding for routine staining. Another set of tissues were fixed in Neutral Buffered Formalin for testicular immunostaining techniques for expression of Vimentin, Desmin, Cytokeratin and Smooth Muscle Actin. There is an increase in seminiferous luminal area in the mature catfish testis with the presence of mature spermatozoa in the lumen when compared with immature catfish testis which has small size of lumen with absence of mature spermatozoa. Testicular interstitium thickness remain relatively unchanged. SMA was markedly expressed in the cytoplasm of interstitial Leydig cells in the immature catfish testis whereas it was weak in its expression in the mature catfish. However, SMA was not expressed in the connective tissue proper in the testicular interstitium. Cytokeratin expression was also marked in the testicular capsule of immature catfish but was weak to absent in the mature catfish, however, both mature and immature catfish had moderate cytokeratin expression in their seminiferous tubule basement membrane. Desmin was strongly expressed in cytoplasm of immature germinal cells in the immature catfish testis but was moderate in its expression in the mature catfish testis. Vimentin expression was marked in the cytoplasm of immature germinal cells in both immature and mature catfish testis but weak in its expression in the Sertoli cell cytoplasm of both groups. This study infers that ultra-structural and protein changes can be related to age changes alone apart from the contribution of seasonality and external interference by ecotoxins. The age-related changes seen in this study could set ``baseline information. The extent of contribution of season and other external factors will be better understood. Though the age-related difference might be peculiar to the species of current interest, the differences elucidated are a sound background for relational studies, especially on the effect of ecologic toxins on immature testis, as separate from the mature testis.

Overexpression of Arabidopsis FLOWERING LOCUS T (FT) gene improves floral development in cassava (Manihot esculenta, Crantz).

Cassava is a tropical storage-root crop that serves as a worldwide source of staple food for over 800 million people. Flowering is one of the most important breeding challenges in cassava because in most lines flowering is late and non-synchronized, and flower production is sparse. The FLOWERING LOCUS T (FT) gene is pivotal for floral induction in all examined angiosperms. The objective of the current work was to determine the potential roles of the FT signaling system in cassava. The Arabidopsis thaliana FT gene (atFT) was transformed into the cassava cultivar 60444 through Agrobacterium-mediated transformation and was found to be overexpressed constitutively. FT overexpression hastened flower initiation and associated fork-type branching, indicating that cassava has the necessary signaling factors to interact with and respond to the atFT gene product. In addition, overexpression stimulated lateral branching, increased the prolificacy of flower production and extended the longevity of flower development. While FT homologs in some plant species stimulate development of vegetative storage organs, atFT inhibited storage-root development and decreased root harvest index in cassava. These findings collectively contribute to our understanding of flower development in cassava and have the potential for applications in breeding.

Impact of oral silymarin on virus- and non-virus-specific T-cell responses in chronic hepatitis C infection.

Silymarin displays anti-inflammatory effects on T lymphocytes in vitro. The immunomodulatory properties of oral silymarin in vivo in humans with chronic hepatitis C have not previously been characterized. We hypothesized that silymarin would suppress T-cell proliferation and pro-inflammatory cytokine production of virus- and non-virus-specific T cells while increasing anti-inflammatory IL-10 production in vivo. Patients from one site of the SyNCH-HCV double-masked, placebo-controlled study of oral silymarin in prior interferon nonresponders with chronic hepatitis C provided blood samples at baseline and treatment week 20. Mononuclear cells were stimulated with recombinant HCV proteins and controls in (3) H-thymidine proliferation assays, IFNγ ELISPOT and IL-10 ELISPOT. The frequency of CD4(+) CD25(hi) and CD4(+) foxp3(+) regulatory T cells, serum cytokine levels, serum IP-10 and lymphocyte interferon-stimulated gene expression were also quantified at baseline and week 20. Thirty-two patients were recruited (10; placebo, 11; 420 mg three times a day, 11; 700 mg three times a day). Serum ALT and HCV RNA titres did not change in any group. HCV-specific CD4(+) T-cell proliferation and the frequency of IFNγ- and IL-10-producing T cells were not significantly changed in silymarin-treated subjects. However, C. albicans-induced T-cell IFNγ and phytohaemagglutinin-induced T-cell proliferation were suppressed by silymarin therapy. A trend towards augmentation of interferon-induced ISG15 expression was present in the high-dose silymarin group. While no effect on HCV-specific T cells was identified, these data confirm that high-dose oral silymarin exerts modest nonspecific immunomodulatory effects in vivo. The impact of this anti-inflammatory effect on long-term liver health in chronic hepatitis C merits future clinical investigation.

Functional assessment of the Medicago truncatula NIP/LATD protein demonstrates that it is a high-affinity nitrate transporter.

The Medicago truncatula NIP/LATD (for Numerous Infections and Polyphenolics/Lateral root-organ Defective) gene encodes a protein found in a clade of nitrate transporters within the large NRT1(PTR) family that also encodes transporters of dipeptides and tripeptides, dicarboxylates, auxin, and abscisic acid. Of the NRT1(PTR) members known to transport nitrate, most are low-affinity transporters. Here, we show that M. truncatula nip/latd mutants are more defective in their lateral root responses to nitrate provided at low (250 µm) concentrations than at higher (5 mm) concentrations; however, nitrate uptake experiments showed no discernible differences in uptake in the mutants. Heterologous expression experiments showed that MtNIP/LATD encodes a nitrate transporter: expression in Xenopus laevis oocytes conferred upon the oocytes the ability to take up nitrate from the medium with high affinity, and expression of MtNIP/LATD in an Arabidopsis chl1(nrt1.1) mutant rescued the chlorate susceptibility phenotype. X. laevis oocytes expressing mutant Mtnip-1 and Mtlatd were unable to take up nitrate from the medium, but oocytes expressing the less severe Mtnip-3 allele were proficient in nitrate transport. M. truncatula nip/latd mutants have pleiotropic defects in nodulation and root architecture. Expression of the Arabidopsis NRT1.1 gene in mutant Mtnip-1 roots partially rescued Mtnip-1 for root architecture defects but not for nodulation defects. This suggests that the spectrum of activities inherent in AtNRT1.1 is different from that possessed by MtNIP/LATD, but it could also reflect stability differences of each protein in M. truncatula. Collectively, the data show that MtNIP/LATD is a high-affinity nitrate transporter and suggest that it could have another function.

End-stage renal disease and African American race are independent predictors of mild liver fibrosis in patients with chronic hepatitis C infection.

Recipients of haemodialysis for end-stage renal disease (ESRD) have a higher prevalence of hepatitis C virus (HCV) infection relative to the general US population. However, the natural course of HCV infection in patients with renal failure, including African Americans (AAs) and Caucasian Americans (CAs), is not well known. We compared the degree of liver inflammation and fibrosis in AA and CA patients with HCV infection, with and without ESRD. This was a cross-sectional study of 156 HCV patients with ESRD (130 AAs and 26 CAs) with a liver biopsy between 1992 and 2005. The control group consisted of 138 patients (50 AAs; 88 CAs) with HCV infections and a serum creatinine <1.5 mg/dL with a liver biopsy between 1995 and 1998. Specimens were graded for inflammation and fibrosis using Knodell histological activity index. Compared to patients without renal impairment, HCV patients with renal failure were older and more likely to be AA. Patients with renal impairment had lower mean serum transaminases, a higher mean serum alkaline phosphatase levels (all P < 0.0001) and less hepatic necro-inflammation (Knodell histological activity index -I, II and III; P < 0.05) and fibrosis (Knodell histological activity index -IV; P < 0.0001). There were no racial differences in serum liver chemistry and histology scores among patients with renal failure. In a multivariate analysis, younger age, ESRD, AA race and a lower serum alkaline phosphatase were associated with lower odds for advanced liver fibrosis. Thus, HCV patients with ESRD had a lower degree of hepatic inflammation and fibrosis compared to those without renal disease, independent of race.

Photographic and radiograpic study of osteological abnormalities of the head of adult African catfish (Clarias gariepinus) / Estudio fotográfico y radiográfico de las anomalías osteológicas de la cabeza del pez gato africano adulto (Clarias gariepinus)

Radiography is a practical screening tool to detect subtle skeletal abnormalities in the adult catfish. Systematic identification of skeletal abnormalities in vertebrates provides an insight into the pathogenesis of skeletal disorders. In the present study; we conducted a mutagenesis screen for skeletal dysplasias in adult catfish, using photography and radiography to assess abnormalities in skeletal anatomy and bone morphology of the head. Two of the fish had skeletal protuberances on the head, while the third had a skeletal depression on the head with associated jaw deformity. However, there was no spinal involvement or other skeletal abnormalities. This study suggests a need for closer monitoring of cultured fish species; including dietary and nutritional requirements, breeding and exposure to pollution and pollutants.

La radiografía es una herramienta práctica de la investigación que fue utilizada para detectar sutiles alteraciones esqueléticas en el pez gato adulto. La identificación sistemática de las anomalías esqueléticas de los vertebrados da una idea de la patogénesis de los trastornos esqueléticos. En el presente estudio, se realizó una pantalla de mutagénesis de displasias esqueléticas en el pez gato adulto, utilizando la fotografía y la radiografía para evaluar las anomalías en la anatomía del esqueleto y la morfología ósea de la cabeza. Dos de los peces tenían protuberancias óseas en la cabeza, mientras que el tercero tenía una depresión ósea en la cabeza asociada a deformidades de la mandíbula. Sin embargo, no hubo participación de la columna vertebral u otras anomalías esqueléticas. Este estudio sugiere la necesidad de una vigilancia más estrecha de las especies de peces cultivados, incluyendo dietética, nutrición, reproducción y exposición a la contaminación y los contaminantes.

Liveweight and chest girth correlation in commercial sheep and goat herds in Southwestern Nigeria / Correlación entre peso vivo y contorno del pecho en rebaños ovino y caprino comerciales en el Suroeste de Nigeria

The correlation between chest girth and weight of sheep and goats have been studied as a predictive guide in homestead farms where equipment to definitively quantify the weight of animals are unavailable and inaccessible. The livestock markets in the South Western part of Nigeria are still very underdeveloped and consist of peasant farmers taking their few animals to more developed areas to offer them for better prices to the consumer or middle men who are in the trade to attain the best profit. Twenty each of sheep and goats were randomly selected in herds from three different commercial locations and evaluated using weight and chest girth measurements as indices. Mean weight for the 3 groups of sheep was between 19.8 and 31.15kg, while for the 3 groups of goats was between 19.6 and 16.35kg. There was correlation (0.39-0.80) between sheep chest girth and weight which does not differ from those already established in literature and apredictive index of W= (18.9 +/- 0.36) CG where in more than 80 percent of the population are accounted for and in goats, correlation of 0.40-0.76 and a predictive index of W= (18.51 +/-0.31) CG where more than 76 percent of the population falls in. It was therefore concluded that chest girth is a useful tool in predicting weight of commercial sheep and goat.

La correlación entre la circunferencia de pecho y el peso de las ovejas y cabras ha sido estudiada como una guía de predicción en granjas, donde el equipo para cuantificar el peso de los animales no está disponible o es de difícil acceso. Los mercados de ganado en la parte sur-occidental de Nigeria, siguen siendo aún muy subdesarroliados y constan de campesinos que tienen pocos animales, a diferencia de zonas más desarrolladas, para ofrecer los mejores precios para el consumidor quienes están los comercializan para alcanzar el mejor beneficio. Veinte ovejas y veinte cabras fueron seleccionadas al azar entre los rebaños de tres diferentes localidades comerciales, y fueron evaluadas utilizando el peso y la circunferencia de pecho como los índices de mediciones. La media de peso de los 3 grupos de ovejas fue entre 19,8 y 31,15kg, respectivamente, mientras que para los 3 grupos de cabras fue entre 19,6 y 16,35kg. Hubo correlación (0,39-0,80) entre la circunferencia de pecho de las ovejas y el peso, que no difieren de las ya establecidas en la bibliografía y un índice predictivo de W = (18,9 +/- 0,36) CG en donde más del 80 por ciento de la población se contabilizan y en el ganado caprino, la correlación de 0,40-0,76 y un índice predictivo deW = (18,51 +/- 0,31)CG donde se encuentra más del 76 por ciento de la población. Por lo tanto, se llegó ala conclusión que la circunferencia de pecho es una herramienta útil en la predicción del peso vivo de las ovejas y cabras comerciales.

Cytochrome c: a non-invasive biomarker of drug-induced liver injury.

Limitations of existing biomarkers to detect liver injury in experimental animals highlight the need for additional tools to predict human toxicity. The utility of cytochrome c (cyt c) as a biomarker in serum and urine was evaluated in two rodent liver injury models. Adult Sprague-Dawley rats treated with acetaminophen or D-galactosamine (GalN) showed dose- and time-dependent histomorphological changes and TUNEL staining in liver consistent with hepatocellular necrosis, apoptosis and inflammation up to 72 h. Matching changes in serum alanine transaminase (ALT), aspartate transaminase (AST) and cyt c peaked at 24 h for either drug at the highest dose, cyt c falling rapidly at 48 hours with ALT and AST remained high. Intracellular transit of cyt c from mitochondria to the cytoplasm in damaged hepatocytes, and then to peripheral circulation, was observed by immunohistochemistry. Correlation coefficients between cyt c and serum diagnostic tests indicate the liver to be the primary source of cyt c. Urinary analysis for cyt c revealed time-dependent increase at 6 h, peaking at 24 h in GalN-treated rats in contrast with irregular patterns of urinary ALT and AST activity. Histological changes detected at 6 h preceded altered ALT, AST and cyt c at 12 and 18 h, respectively, in GalN-treated rats. These studies demonstrate cyt c to be a useful indicator of hepatic injury in rodents and support its utility as a non-invasive predictor of drug-induced hepatotoxicity, when utilized as a potential urinary biomarker.

Effect of Lactobacillus reuteri on intestinal resistance to Cryptosporidium parvum infection in a murine model of acquired immunodeficiency syndrome.

Efficacy of Lactobacillus reuteri as a probiotic for the control of Cryptosporidium parvum infection was evaluated in C57BL/6 female mice that were immunosuppressed by intraperitoneal inoculation with the LP-BM5 leukemia virus. Four months after inoculation, mice developed lymphadenopathy, splenomegaly, and susceptibility to C. parvum infection. After daily prefeeding with L. reuteri (10(8) cfu/day) for 10 days, mice were challenged with 6.5 x 10(6) C. parvum oocysts and fed L. reuteri during the entire study. Mice supplemented with L. reuteri and challenged with C. parvum cleared parasite loads from the gut epithelium. However, unsupplemented animals developed persistent cryptosporidiosis and shed high levels of oocysts in the feces. L. reuteri feeding increased its colonization of the intestinal tract, which was inversely related to the fecal shedding of oocysts. These findings suggest that L. reuteri may help prevent C. parvum infection in immunodeficient subjects.

Cytokine production in vitro by macrophages of goats with caprine arthritis-encephalitis.

The response of caprine macrophages to exposure to caprine arthritis-encephalitis virus (CAEV) and lipopolysaccharide (LPS) was investigated in female Nubian and Nubian crossbreed of goats. Macrophages were matured in vitro from monocytes isolated from blood of control and CAEV-infected goats and the concentrations of tumor necrosis factor (TNF-alpha) and interleukin-6 (IL-6) in culture supernatant after exposure of cells to LPS and virus were assayed. Though barely detectable in unstimulated cells, TNF-alpha and IL-6 levels showed peak values of 420 +/- 28 to 530 +/- 32 and 70 +/- 27 to 93 +/- 29, respectively, in supernatants of control goat cells [corrected], remaining high through 24 hrs. post treatment with LPS stimulation. Exposure of these control goat cells [corrected] to virus induced lower secretions (p<0.05) of the cytokines. The peak values occurred between 6 and 12 hrs. post treatment with LPS or virus. Cells prepared from virus-infected goats and treated with the mitogen or virus showed significantly (p<0.05) lower response than those from control goats. The present results suggest a dysregulation, possibly downregulation of the production of both cytokines in macrophages of goats chronically diseased by lentivirus infection.

The response of goat brain cells to infection by caprine arthritis-encephalitis virus.

Caprine arthritis-encephalitis virus is a lentivirus of goats causing encephalomyelopathy acutely in young goats and occasionally in late stages of chronically infected adult goats. To determine the specific brain cells infected by the virus and the response of other cell types, goat cerebrum explant cultures prepared from newborn goat kids were infected by virus application. Infection of brain cultures was also possible by coculture with virus-infected macrophages. Predominantly, microglia cells were specifically infected by the virus, resulting in death of more than 50% of the cells within 2 weeks of infection. Infected cells enlarged and formed multinucleated giant cells. Infection of oligodendrocytes was observed, but infrequently. Astrocytes were not infected. Proviral deoxyribonucleic acid (DNA) was detected in infected cultures by amplification of a 490 base-pair fragment of the viral gag gene by the polymerase chain reaction (PCR) technique. Virus budding from plasma membrane of infected microglia cells was demonstrated by transmission electron microscopy. The supernatant of infected brain cells induced cytopathic effect when applied to indicator cells. These observations suggest productive infection of brain cultures. Virus infection of neurons was not observed. Culture of neurons in virus-free supernatant of CAEV-infected microglia or mixed glia culture resulted in death of 50% of the neurons in 11 days, suggesting the production of neurotoxic substances by the virus-infected glial cells.

The MPTP-induced parkinsonian syndrome in the goldfish is associated with major cell destruction in the forebrain and subtle changes in the optic tectum.

The neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) can induce a parkinsonian syndrome in humans and nonhuman primates, which is susceptible to treatment and prevention by drugs such as L-DOPA and L-deprenyl. Recently, we have reported that MPTP can also cause a parkinsonian syndrome in the common goldfish, which appears to faithfully mirror the neurochemical and behavioral aspects of the action of MPTP in the higher vertebrates. In addition, we recently identified the likely teleost equivalent of the substantia nigra in the goldfish forebrain, the "nucleus pars medialis," on the basis of its destruction by MPTP and selective protection by the MAO-B blocker L-deprenyl. In the present work we substantiate this conclusion by examining tissue destruction the goldfish forebrain at increasing MPTP concentrations, up to the the LD50 of 200 mg/kg. In addition, we show that at the highest MPTP dose subtle changes also occur with low frequency in nondopaminergic cells in the optic tectum, and in ependymal cells lining the midbrain ventricle. The effects on ependymal cells are similar to those previously noted in the forebrain. We conclude that the goldfish model continues to faithfully mimic the histologic pattern of parkinsonian tissue destruction engendered by MPTP in primate models.

Anxiolytic activity of adenosine receptor activation in mice.

1. Purine analogues have been examined for anxiolytic- and anxiogenic-like activity in mice, by use of the elevated plus-maze. 2. The selective A1 receptor agonist, N6-cyclopentyladenosine (CPA) had marked anxiolytic-like activity at 10 and 50 microg kg(-1), with no effect on locomotor performance at these doses. 3. The A1 selective adenosine receptor antagonist, 1,3-dipropyl-8-cyclopentylxanthine (CPX) had no significant effect on anxiety-related measures or locomotor behaviour, but blocked the anxiolytic-like activity of CPA. The hydrophilic xanthine, 8-(p-sulphophenyl) theophylline did not prevent anxiolysis by CPA. 4. Caffeine had anxiogenic-like activity at 30 mg kg(-1) which was prevented by CPA at 50 micro kg(-1). 5. The A2 receptor agonist, N6-[2-(3,5-dimethoxyphenyl)-2(2-methylphenyl)-ethyl]adenosine (DPMA) had no effect on anxiety behaviour but depressed locomotor activity at the highest dose tested of 1 mg kg(-1). The A2 receptor antagonist, 1,3-dimethyl-l-propargylxanthine (DMPX) had no effect on anxiety-related measures or locomotion and did not modify the anxiolytic-like activity of CPA. 6. Administration of DPMA in combination with anxiolytic doses of CPA prevented the anxiolytic-like activity of the latter. 7. The results suggest that the selective activation of central A1 adenosine receptors induces anxiolytic-like behaviour, while the activation of A2 sites causes locomotor depression and reduces the effects of A1 receptor activation. The absence of any effect of CPX alone suggests that the receptors involved in modulating behaviour in the elevated plus-maze in mice are not activated tonically by endogenous adenosine.

Effect of MPTP on dopaminergic neurons in the goldfish brain: a light and electron microscope study.

The neurotoxin MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) causes a Parkinsonian syndrome in the goldfish (Carassius auratus), characterized by transient bradykinesia, the accumulation of MPP+ in the brain, and a decrease in the forebrain and midbrain content of catecholamines (Pollard et al., FASEB J., 6 (1992) 3108-3116). Using light and electron microscopy, we studied the effect of MPTP on the distribution and ultrastructure of tyrosine hydroxylase (TH)-immunoreactive, dopaminergic neurons, and on the ultrastructure of other selected areas of the goldfish brain. Goldfish were treated with MPTP (50 mg/kg) in the absence or presence of L-deprenyl (10 mg/kg) or clorgyline (10 mg/kg). In the medial part of the central telencephalon, the nucleus telencephali, pars medialis, MPTP caused a decrease in the number of TH-immunoreactive neurons and distortions in their labelling pattern. Electron microscopic observations showed that MPTP caused swelling of cell processes, changes in neuronal nuclear profiles, dilation of endoplasmic reticulum, intracellular vacuolization and membrane distortions, and degeneration of neuronal fibers in this brain area. MPTP also caused a small reduction and some diffuseness in the labelling of dopaminergic neurons in several diencephalic periventricular nuclei. Moreover, MPTP induced cell swelling and degeneration in the subependymal cell layers along the forebrain ventricles. In all areas, L-deprenyl appeared to partially prevent the MPTP-induced degenerative changes. We conclude that in the goldfish MPTP causes marked histochemical changes in selected dopaminergic brain systems coincident with the Parkinson-like locomotor and neurochemical deficits.

Trypanosomosis and reproduction: II. Effect of Trypanosoma vivax infection on pregnancy and post-partum cyclicity in ewes.

The effect of infection with Trypanosoma vivax on pregnancy and post-partum cyclicity in ewes was investigated. Of the 5 ewes infected in the first trimester, 3 died without aborting and 2 after aborting. Intrauterine infection occurred in 2 of the foetuses removed at post mortem. Of the 5 infected in the third trimester, one ewe died without aborting, one lambed prematurely and 3 at term. Intrauterine infection occurred in one of the lambs born at term. None of the lambs were viable. The termination of pregnancy may be as a result of stress. The ewes infected in the third trimester commenced irregular cyclicity 13 to 23 days post partum.

Trypanosomosis and reproduction: I. Effect of Trypanosoma vivax infection on the oestrous cycle and fertility in the ewe.

Ten West African Dwarf ewes were inoculated with Trypanosoma vivax and, at varying intervals, treated subcuratively with diminazene aceturate to maintain the infection. Soon after infection all ewes had anoestrus for 40 to 96 days and 5 died by day 110 post infection. Compared to control animals, infected ewes had prolonged low levels of plasma progesterone until recovery or death. However, no gross or histological lesions were detected in the endocrine or reproductive organs. Of the survivors, the 5 that were aparasitaemic subsequently became pregnant and had normal gestations.

A single-base substitution in exon 6 of the androgen receptor gene causing complete androgen insensitivity: the mutated receptor fails to transactivate but binds to DNA in vitro.

A single-base substitution in the coding region of the androgen receptor (AR) gene caused complete androgen insensitivity in a patient with 46,XY karyotype. The mutation was a T-to-G transition in exon 6 and changed the codon 807 from ATG (methionine) to AGG (arginine) in the hormone-binding domain of the protein. The mutation was inserted into the wild-type human AR cDNA and the resulting cDNA expressed in CV-1 cells. Native and mutated AR proteins synthesized in recipient cells had identical molecular masses. Ligand-binding activity of the mutant receptor was less than 5% of that of the wild-type AR. The mutant's interaction with an androgen-response element in vitro was identical to that of the native aporeceptor; however, it did not transactivate a reporter gene construct in transfected CV-1 cells. Androgen insensitivity in our patient was thus due to altered structure of the receptor's steroid-binding region, which prevented the mutated AR from gaining a transcriptionally active form in vivo.

Plasma progesterone, estradiol-17 beta and testosterone in maternal and cord blood, and maternal human chorionic gonadotropin at parturition.

To understand the endocrine control of normal parturition in man and interactions of foetal and maternal hormones involved, it is desirable to estimate the hormone levels in the maternal and foetal blood around parturition time. Blood was obtained from the umbilical vessels of 22 male and 30 female neonates and the antecubital veins of their mothers during labour at term. The maternal and neonatal plasma levels of progesterone (P), testosterone (T) and estradiol-17 beta (E2) and maternal plasma levels of human chorionic gonadotrophin (hCG) were determined by radioimmunoassay (RIA). The effect of the foetal sex on the maternal hormones at term was also evaluated. Mean values, with the standard errors of means, of plasma, P, T and E2 in cord blood were 5.3 +/- 0.3, 8.4 +/- 1.2 and 5.0 +/- 0.3 ng/ml, respectively; in the maternal plasma the values were 18.2 +/- 1.2, 1.2 +/- 0.1 and 4.3 +/- 0.4 ng/ml, respectively. The mean T level was significantly higher in cord than in maternal blood, while P was significantly higher in the maternal than in cord blood. The plasma concentrations of P, T and E2 in the mothers delivering male babies were 16.9 +/- 2.2, 1.2 +/- 0.4 and 4.5 +/- 0.7 ng/ml, respectively; in those delivering female babies, the levels were 16.1 +/- 2.4, 1.1 +/- 0.1 and 4.3 +/- 0.4 ng/ml, respectively. Mean plasma levels of hCG in the women was 0.9 +/- 0.1 microgram/ml with no significant difference between the values in the mothers of male and female babies.(ABSTRACT TRUNCATED AT 250 WORDS)

L-deprenyl confers specific protection against MPTP-induced Parkinson's disease-like movement disorder in the goldfish.

Administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to the goldfish causes a reversible, Parkinson's disease-like syndrome which includes loss of noradrenaline and dopamine from the brain, accumulation of the toxic metabolite 1-methyl-4-phenylpyridinium species (MPP+), and substantial reduction in movement. L-Deprenyl, a selective monoamine oxidase-B inhibitor, protects the goldfish from loss of movement, but clorgyline, a selective monoamine oxidase-A inhibitor, has no such protective action. L-Deprenyl and clorgyline primarily inhibit goldfish brain monoamine oxidase-B and monoamine oxidase-A, respectively. The mechanism by which MPTP causes reduced movement in goldfish is to cause an increase in resting time. Otherwise normal average velocity occurred during periods of movement. L-Deprenyl protection results in entirely 'normal' levels of resting time and average velocity during times of movement. Equivalent observations regarding l-deprenyl and clorgyline have been made in primate models of MPTP toxicity, and l-deprenyl is used for treatment of Parkinson's disease in humans. Therefore it is suggested that the evolutionarily equivalent subcortical circuitry and neural density of the goldfish brain may provide a useful model upon which to search for drugs relevant to human Parkinson's disease.