HIV Knowledge and Screening Practices among In-School Adolescents in a Semi-Urban Community of Osun State, Southwest Nigeria.

BACKGROUND: Adolescents and youths are currently one of the main sub-populations responsible for most Human Immunodeficiency Virus (HIV) new cases in Nigeria due to their high-risk sexual practices. Yet, most Nigerian adolescents have poor HIV knowledge and are not aware of their HIV status. STUDY OBJECTIVES: We assessed respondents' HIV knowledge, their attitude to screening, testing practice and identified predictors of HIV screening among youths (15-24 years old) in Iwo, Osun State, Nigeria. METHODS: Cross-sectional design was employed and a multistage sampling method was used to recruit 360 eligible schooling youths in three secondary schools (private and public coeducational schools). A semi-structured, interviewer administered questionnaire was used for data collection. Both descriptive and inferential statistics were carried out at p<0.05. RESULTS: Mean age (±SD) of the respondents was 15±4.71 years. The majority (75.6%) of the respondents had heard about HIV. Overall, only 57.6% of respondents possessed a comprehensive knowledge of HIV but a majority (80.6%) of them had a positive attitude to HIV screening. Only 20.6% of the respondents had ever screened for HIV, 70.0% of them had pre-and post-test counselling. The most prevalent reason for non-screening is fear of getting a positive result (48.3%). Predictors of HIV screening uptakes included respondents' age (AOR = 2.95; 95%CI = 2.25-6.01), school type (AOR = 2.9;95%CI = 1.99-11.25), class level (AOR = 3.21;95% CI = 2.13-8.12) and attitude to screening (AOR = 2.51;95% CI = 2.01-6.39). CONCLUSION: Despite a high awareness rate and overwhelming positive attitude, HIV screening practice was low in the study setting. There is a need for health policymakers to further prioritise adolescents and youths in the race to end HIV epidemics in Nigeria.

CONTEXTE: Les adolescents et les jeunes sont actuellement l'une des principales sous-populations responsables de la plupart des nouveaux cas de virus de l'immunodéficience humaine (VIH) au Nigeria en raison de leurs pratiques sexuelles à haut risque. Pourtant, la plupart des adolescents nigérians ont une faible connaissance du VIH et ne sont pas conscients de leur statut sérologique. OBJECTIFS DE L'ÉTUDE: Nous avons évalué les connaissances des répondants sur le VIH, leur attitude à l'égard du dépistage, les pratiques de dépistage et identifié les facteurs prédictifs du dépistage du VIH chez les jeunes (15-24 ans) à Iwo, dans l'État d'Osun, au Nigeria. MÉTHODES: Une étude transversale a été employée et une méthode d'échantillonnage à plusieurs niveaux a été utilisée pour recruter 360 jeunes scolarisés éligibles dans trois écoles secondaires (privées et publiques). Un questionnaire semi-structuré, administré par un enquêteur, a été utilisé pour la collecte des données. Des statistiques descriptives et inférentielles ont été réalisées à p<0,05. RÉSULTATS: L'âge moyen (±SD) des personnes interrogées était de 15±4,71 ans. La majorité (75,6 %) des personnes interrogées avaient entendu parler du VIH. Dans l'ensemble, seulement 57,6 % des personnes interrogées avaient une connaissance approfondie du VIH, mais la majorité d'entre elles (80,6 %) avaient une attitude positive à l'égard du dépistage du VIH. Seules 20,6 % des personnes interrogées avaient déjà effectué un dépistage du VIH, mais 70 % d'entre elles avaient bénéficié d'un conseil avant et après le test. La raison la plus fréquente de l'absence de dépistage est la peur d'obtenir un résultat positif (48,3 %). Les facteurs prédictifs de la participation au dépistage du VIH comprenaient l'âge des répondants (AOR=2,95 ; 95%CI=2,25-6,01), le type d'école (AOR=2,9;95%CI=1,99-11,25), le niveau de classe (AOR=3,21;95% CI=2,13-8,12) et l'attitude à l'égard du dépistage (AOR=2,51;95% CI=2,01-6,39). CONCLUSION: Malgré un taux de sensibilisation élevé et une attitude très positive, la pratique du dépistage du VIH était faible dans le contexte de l'étude. Il est nécessaire que les décideurs en matière de santé accordent une plus grande priorité aux adolescents et aux jeunes dans la course à l'éradication de l'épidémie de VIH au Nigéria. Mots clés: VIH/SIDA, Adolescents, Jeunes, Jeunes, Nigeria.

Occurrence of pathogens in wild rodents caught on Swedish pig and chicken farms.

A total of 207 wild rodents were caught on nine pig farms, five chicken farms and five non-farm locations in Sweden and surveyed for a selection of bacteria, parasites and viruses. Lawsonia intracellularia and pathogenic Yersinia enterocolitica were only detected in rodents on pig farms (9% and 8% prevalence, respectively) which indicate that these agents are more likely to be transmitted to rodents from pigs or the environment on infected farms. Brachyspira hyodysenteriae (1%), Brachyspira intermedia (2%), Campylobacter jejuni (4%), Campylobacter upsaliensis (2%), leptospires (7%) and encephalomyocarditis virus (9%) were also detected from rodents not in contact with farm animals. Giardia and Cryptosporidium spp. were common, although no zoonotic types were verified, and Salmonella enterica was isolated from 1/11 mice on one farm but not detected by PCR from any of the rodents. Trichinella spp. and Toxoplasma gondii were not detected.

Knowledge, attitudes and perceptions of epilepsy among secondary school teachers in Osogbo South-West Nigeria: a community based study.

BACKGROUND: The attitudes toward people with epilepsy are influenced by the degree of knowledge of the condition. The social problems encountered by school children with epilepsy as a result of negative attitude and beliefs are quite enormous. OBJECTIVES: The study therefore looked at the knowledge, attitudes, and perceptions of teachers, who see a lot of epileptics, relate to them on a daily basis and have influence on them. MATERIALS AND METHODS: A cross-sectional survey, using a self-administered questionnaire obtained from the author of a similar study in the United States, was carried out among 269 school teachers randomly selected from various secondary schools in Osogbo, the Osun State capital in South-West Nigeria. The questionnaire included the scale of attitudes toward persons with epilepsy and knowledge about epilepsy as well as demographic and teaching experience survey among others. RESULTS: Despite the high level of education of the teachers ranging from Masters Degree to National Certificate in Education, there were significant deficits in terms of general knowledge about epilepsy (70% of the respondents reported their general knowledge about epilepsy in the lower half of the scale). There was also poor knowledge of the first aids measures in the classrooms. Below one-third (29.2%) felt it was contagious and 40% of respondents reported that sufferers should not be kept in regular classes. However, their attitudes toward epilepsy were generally positive. CONCLUSIONS AND RECOMMENDATIONS: We concluded that teachers need to have health education courses on common disease conditions such as epilepsy that are prevalent in school age; this might help to reduce the prejudice and increase the acceptance of epileptic individuals in the classrooms. Also, generally public health campaigns should be encouraged in this field.

Medical mortality in an emergency department in Nigeria: the transition is obvious!

INTRODUCTION: The emergency department (ED), a major entry point into the hospital, provides an insight to the type of cases seen, the quality of care and mortality spectrum in a health institution. We aim to identify the spectrum of medical causes of mortality in our ED, the demographic pattern and duration of stay before death. METHOD: This is a retrospective study that looked at medical mortality in the ED from January 2004 to December 2009. We obtained data on the demographics and causes of death from the medical records and case notes of the deceased. RESULTS: A total of 16587 patients were admitted during the period under review, of these 1262 (7.61%) died in the ED. The male to female ratio was 1.58:1.0 [772 males (61.2%), and 489 females (38.8%)]. Mortality was highest among the 20-45 years age range, followed by 46-65 years, >65 years and < 20 years in decreasing frequency [589(46.7%), 421(33.4%), 186 (14.8%) and 66(5.2%) respectively]. The three most common causes of death were stroke 315(25%), HIV related illnesses 126(10.0%), and heart failure 123(9.7%). Most deaths occurred less than 24hours of admission, 550(43.6%), followed by one day (36.0%) and two days (10.8%) post admissions respectively. CONCLUSION: The commonest cause of death in the ED was stroke. The burden of death was highest in the younger age group, with most occurring less than 24 hours of admission.

The trend of HIV infection in Kano, Nigeria--a seven-year study of adult attendees of Aminu Kano Teaching Hospital.

BACKGROUND: Human immunodeficiency virus (HIV) infection is a huge concern with increasing epidemic proportions The consequences are devastating in developing countries particularly in large areas of southeast Asia and sub Saharan Africa including decrease in life-expectancy, huge loss of manpower and a heavy economic and social burden. Sub-Saharan Africa has been hit harder by HIV/AIDS pandemic than any other region of the world At the end of 2006, the Joint United Nations Programme on HIV/AIDS (UNAIDS) estimated that, globally 39.5 million people were living with HIV/AIDS, out of which 24.7 million were in sub-Saharan Africa. To determine the annual trend of HIV infection in Kano as well as the seroprevalence rates over the years. METHOD: This retrospective study includes all adults that are 15years and above, who are also AKTH attendees and. patients referred from other hospitals in Kano, who, based on clinical suspicion, were sent to the serology laboratory of the hospital for HIV screening and confirmation between January, 1997 and December, 2003. It however, excludes all pediatrics, antenatal care clinic attendees and all blood donors screened for HIV antibodies within the period. These have been collated under various risk groups elsewhere. RESULTS: Of 9241 subjects tested, 3217 (34.8%) were confirmed seropositive for HIV antibodies consisting of 1908 (36.7%) and 1441 (35.7%) males and females respectively Analysis of results on yearly basis shows prevalence rates of 37.1% in 1997, 40% in 1998 and 47.9% in 1999. However, the HIV seroprevalence rates declined to 22.6% among these subjects in 2000 before rising to the peak (48.8%) in 2002 from 30% seroprevalence of the previous year, 2001. The prevalence rate for 2003 was 32.1%. effective control strategies aimed at curbing the spread of HIV infection.

Malaria-induced anaemia and serum micronutrients in asymptomatic Plasmodium falciparum infected patients.

Interaction between malaria, anaemia and malnutrition is poorly understood in asymptomatic malaria patients. This information is important in the management of malaria infection in many endemic regions in sub-Saharan Africa. Malaria parasitaemia, full blood counts and serum levels of essential micronutrients particularly iron (Fe), zinc (Zn) and copper (Cu) of the patients attending Health Centres in Ilorin, Kwara state were investigated using microscope, auto-haemanalyzer and atomic absorption spectrophotometer respectively. A total of 123 (55.2%) of our study population were positive of Plasmodium falciparum. Infection was age-specific (p < 0.0001), and a significant proportion (88.6%) of malaria infected patients were 28.5% mild, 45.5% moderate and 14.6% severely anaemic. The severity of anaemia increases as parasite density increases. Analysis of serum micronutrients revealed a significant low level of iron (3.72 mg/l), copper (2.05 mg/l) and zinc (3.67 mg/l) in infected patients (p < 0.0001); which further increased their anaemic condition. This study confirmed a significant relationship between severity of anaemia and nutritional deficiency in the pathogenesis of malaria infection. We therefore, recommend that immunomodulation potential of micronutrients may be essential in the management of malaria infection.

Characteristics, management, and outcomes of patients with hepatocellular carcinoma in Africa: a multicountry observational study from the Africa Liver Cancer Consortium.

BACKGROUND: Hepatocellular carcinoma is a leading cause of cancer-related death in Africa, but there is still no comprehensive description of the current status of its epidemiology in Africa. We therefore initiated an African hepatocellular carcinoma consortium aiming to describe the clinical presentation, management, and outcomes of patients with hepatocellular carcinoma in Africa. METHODS: We did a multicentre, multicountry, retrospective observational cohort study, inviting investigators from the African Network for Gastrointestinal and Liver Diseases to participate in the consortium to develop hepatocellular carcinoma research databases and biospecimen repositories. Participating institutions were from Cameroon, Egypt, Ethiopia, Ghana, Ivory Coast, Nigeria, Sudan, Tanzania, and Uganda. Clinical information-demographic characteristics, cause of disease, liver-related blood tests, tumour characteristics, treatments, last follow-up date, and survival status-for patients diagnosed with hepatocellular carcinoma between Aug 1, 2006, and April 1, 2016, were extracted from medical records by participating investigators. Because patients from Egypt showed differences in characteristics compared with patients from the other countries, we divided patients into two groups for analysis; Egypt versus other African countries. We undertook a multifactorial analysis using the Cox proportional hazards model to identify factors affecting survival (assessed from the time of diagnosis to last known follow-up or death). FINDINGS: We obtained information for 2566 patients at 21 tertiary referral centres (two in Egypt, nine in Nigeria, four in Ghana, and one each in the Ivory Coast, Cameroon, Sudan, Ethiopia, Tanzania, and Uganda). 1251 patients were from Egypt and 1315 were from the other African countries (491 from Ghana, 363 from Nigeria, 277 from Ivory Coast, 59 from Cameroon, 51 from Sudan, 33 from Ethiopia, 21 from Tanzania, and 20 from Uganda). The median age at which hepatocellular carcinoma was diagnosed significantly later in Egypt than the other African countries (58 years [IQR 53-63] vs 46 years [36-58]; p<0·0001). Hepatitis C virus was the leading cause of hepatocellular carcinoma in Egypt (1054 [84%] of 1251 patients), and hepatitis B virus was the leading cause in the other African countries (597 [55%] of 1082 patients). Substantially fewer patients received treatment specifically for hepatocellular carcinoma in the other African countries than in Egypt (43 [3%] of 1315 vs 956 [76%] of 1251; p<0·0001). Among patients with survival information (605 [48%] of 1251 in Egypt and 583 [44%] of 1315 in other African countries), median survival was shorter in the other African countries than in Egypt (2·5 months [95% CI 2·0-3·1] vs 10·9 months [9·6-12·0]; p<0·0001). Factors independently associated with poor survival were: being from an African countries other than Egypt (hazard ratio [HR] 1·59 [95% CI 1·13-2·20]; p=0·01), hepatic encephalopathy (2·81 [1·72-4·42]; p=0·0004), diameter of the largest tumour (1·07 per cm increase [1·04-1·11]; p<0·0001), log α-fetoprotein (1·10 per unit increase [1·02-1·20]; p=0·0188), Eastern Cooperative Oncology Group performance status 3-4 (2·92 [2·13-3·93]; p<0·0001) and no treatment (1·79 [1·44-2·22]; p<0·0001). INTERPRETATION: Characteristics of hepatocellular carcinoma differ between Egypt and other African countries. The proportion of patients receiving specific treatment in other African countries was low and their outcomes were extremely poor. Urgent efforts are needed to develop health policy strategies to decrease the burden of hepatocellular carcinoma in Africa. FUNDING: None.

Knowledge and perception of stroke among adults in Osogbo, Nigeria.

Stroke is a major cause of neurological admission in Nigeria. Its prevention has been reported to be dependent on public knowledge of stroke warning signs and risk factors. Ignorance of stroke risk factors and inability to control such risk factors may contribute to high prevalence of stroke among blacks. This cross-sectional descriptive study therefore investigated knowledge and perception of stroke among adults living in Osogbo, Nigeria. Multistage sampling technique was used to select a sample of 900 adults aged between 18 and 80 years as at their last birthday. Data were collected using a pretested modified version of instrument used in a previous study. Data collected from the final survey instrument were analyzed using both descriptive and inferential statistics. A total of 900 adults with male to female ratio of 1.4:1 and mean age 43.6+/-17.63 years participated in this study. Four hundred and seven (45.2%) of the interviewees reported that they were hypertensive. Heart was incorrectly identified by 54% of the respondents as injured organ during stroke. Majority (83.0%) of the respondents indicated that stroke was preventable whereas only 37.1% of them were aware of stroke recurrence. The most common stroke risk factors listed by the respondents were hypertension (78.2%) stress (59.9%) and old age (58.3%). Stroke survivors were perceived by 68.7% of the respondents as being able to return to activities of daily living but with diminished quality of social life. Knowledge of stroke warning signs and risk factors was good among the respondents. However, their baseline knowledge about stroke was poor. Stroke survivors were perceived as being unable to return to pre-stroke's quality of social life. Development of educational strategies to enlighten the public about stroke is therefore recommended.

Thermal conductivity of soils with heavy metals concentration from the Niger Delta region of Nigeria.

This paper presents the characteristic thermal and chemical properties of some surface soil samples from the oil-producing regions of Nigeria. A microprocessor-based thermal analyzer was used to determine the thermal conductivity while spectrophotometric procedure was employed to conduct the heavy metal concentration analysis. Thermal conductivity values were compared with heavy metal concentrations in each soil sample. The values of lead and cadmium and their respective measured thermal conductivities were highly correlated, with their correlation coefficients both greater than 0.900, while other metals showed no correlation.

Effectiveness of different approaches to mass delivery of praziquantel among school-aged children in rural communities in Nigeria.

Schistosomiasis is hyperendemic in Nigeria. The national policy on schistosomiasis control has adopted praziquantel as the main drug of use in the control strategy aimed at reducing morbidity. However, the best delivery channel for praziquantel in schistosomiasis control in Nigeria is yet to be determined. This study assessed different channels for praziquantel delivery in a mass treatment effort. Three groups, each of two communities, were assigned to one of the following three channels: health facility (HF), school, and community for mass delivery of praziquantel to school-aged children. Distributors were trained on all aspects of praziquantel distribution and sufficient praziquantel tablets were provided for the drug distribution within 3 weeks following which an evaluation of the drug distribution by the different treatment channels was conducted. Overall, the community channel of delivery achieved the best coverage of 72.2% (range: 69-73%) compared to 44.3% (range: 39.5-62%) and 28.5% (range: 26.3-74.5%) for the HF and school channels, respectively. Community channel of praziquantel delivery as shown in this study ensures good coverage of both in and out-of-school children.

Examination of the compaction properties of a 1:1 acetaminophen:microcrystalline cellulose mixture using precompression and main compression.

The compaction properties of a 1:1 acetaminophen and microcrystalline cellulose (MCC) mixture have been studied using a compaction simulator to make tablets by single compression and by a combination of precompression and main compression. The tensile strengths of the tablets and the energies involved in the compressions were determined. The tensile strengths of the tablets increased with increases in single compression pressure from 80 to 400 MPa and as the total applied pressure increased from 80 MPa up to around 400 MPa when combinations of precompression and main compression pressures were used. The tablet porosity decreased with increase in main compression pressure while the tablet tensile strengths increased. At minimum tablet porosity, further increase in main compression pressure could no longer result in increase in tablet strengths. Tablets compressed with combinations of precompression and main compression were stronger (2.15 +/- 0.02 to 3.99 +/- 0.1 MPa) than those produced with single compression (0.73 +/- 0.01 to 3.09 +/- 0.05 MPa). The total gross energies of compression increased with an increase in pressure of both the precompression and main compression. The elastic energies during main compression increased with an increase in precompression pressure as the tablet exhibited greater elastic deformation and reduced plasticity on second compression. The increase in elastic energies during main compression may also be because elastic energy is recoverable and is independent of precompression. As the precompression pressure increased, the minimum tablet porosity was attained; hence, the plastic energy during main compression became smaller while the elastic energy increased. Thus, a combination of low precompression and main compression pressures of 160/80 MPa or 80/160 MPa are more advantageous in the tableting of the 1:1 acetaminophen:MCC than a high single compression pressure of 320 or 400 MPa.

The effects of lag-time and dwell-time on the compaction properties of 1:1 paracetamol/microcrystalline cellulose tablets prepared by pre-compression and main compression.

The effects of lag-time and dwell-time on the compaction properties of tablets compressed from a 1:1 blend of paracetamol and microcrystalline cellulose have been examined using a compaction simulator. Increases in lag-times (from 0.06 to 0.53 s) resulted in small increases in the tensile strengths of the tablets when combinations of 80 and 160 MPa were used as the compression pressures. Further increases in lag-time did not alter the tablet strengths. When combinations of 240 and 320 MPa were used for pre-compression and main compression, the effects on the tensile strengths were more complex, partly because the high elastic recoveries of the tablets resulted in greater variability in the data. Increases in lag-times from 0.06 to 0.97 s resulted in an increase of between 12 and 28% in tensile strength. Longer lag-times (1.24 or 1.52 s) did not result in further increases in tensile strength. The application of a dwell-time of 0.26 s during pre-compression or main compression pressures of 80 and 160 MPa generally led to a decrease (14-22%) in tensile strength compared with tablets where no dwell-time was used. This was because of increases in both the elastic recoveries and elastic energies. Subsequent increases in dwell-time from 0.26 to 0.9 s resulted in increases in tablet strength compared with that obtained when no dwell-time was applied. The tensile strengths of tablets made with a pre-compression of 160 MPa then a main compression of 80 MPa were 11-33% higher than those of tablets made with a pre-compression of 80 MPa then a main compression of 160 MPa. This was because higher plastic energies and more plastic deformation occurred at the higher pre-compression. Generally, the application of dwell-time resulted in greater increases in tensile strengths than lag-time, which had less effect on the compaction properties.

Cleft lip and palate as seen in the University College Hospital, Ibadan.

The purpose of this study was to update cleft lip and palate anormalies in Nigerian Africans using clinic materials. Hospital available information about records of 45 children with cleft lip and palate were reviewed. The 24 males and 21 females were all seen at the Dental centre, U. C. H., Ibadan during a period of six years. Twice more females than males had complete cleft of the palate and alveolar process on one side of the premaxilla. Majority of the clefts of the soft and hard palates on both sides of the premaxilla occurred in males with a male-to-female ration 6:1. There were several bilateral clefts and a preponderance of left unilateral clefts over clefts on right side. No other clear-cut patterns emerged probably because of small sample size.

Lipoma of the oral cavity: clinicopathological review of seven cases from Ibadan.

This study provides documented basis of oral lipoma experience at the University College Hospital Ibadan. The study reviewed seven cases, seen over a period of 18 years. Peak age of occurrence way 40 years and above. The tongue, and cheek were the predominant sites while the overall incidence was 0.43%. Male to female ratio was 2.5:1. Surgical excision is the only treatment recommended in the present study and no recurrence was recorded in these case treated in this study.

Osteomyelitis mimicking Paget's disease or a pagetoid phenomenon: a case report.

Osteomyelitis is an inflammatory infection of the bone marrow. When the maxillofacial region is involved the mandible is the preferred site in adults and the elderly. Maxillary involvement is usually seen in children with only few cases reported in adults. The disease occurs in stages, with some stages highly mimicking other diseases. Clinicians ought to be aware of the full biological course of osteomyelitis of the jaws to avoid mis-diagnosis or underdiagnosis.

Effects of different brands of fluoride dentifrices on dental caries incidence in the rat.

The effectiveness of 3 different brands of fluoride-containing dentifrices on the prevention of dental caries was investigated in molars of young rats. Forty albino Wistar rats weighing 50-80g, 28 males and 12 females were inoculated in the mouth with streptococcus viridans daily from day 1 to day 5 of the experiment. The animals were then divided into four groups and fed with rat pellets containing 60% sucrose added as granulated sugar. All the groups were given water ad libitum. Group I had daily tooth brushing with water and served as the control while groups II, III and IV received daily brushing of their molar teeth with different fluoride--containing dentifrices: (Maxam, Florish and Close-Up respectively. All topical treatments were given for one minute daily per rat from day 6 to day 56 of the experiment. At the end of the experiment the animals were sacrificed, the jaws removed and the teeth were scored for occlusal caries. All fluoride--containing dentifrices tested reduced caries in the following order: Maxam 37.86%, Florish 59.22% and Close-Up 57.28%. This study confirmed that fluoride incorporated in Florish and Close-Up showed significant levels of caries reduction (P <0.01) and (P <0.05) respectively in the rat. It also adds credence to Dental Health Education in the application of various tooth pastes in oral hygiene measures.

Prevalence of pregnancy related oral granuloma in a Nigerian population group and the possible role of contraceptives.

A clinicopathological survey on pregnancy related tumours was carried out on 400 randomly selected pregnant Nigerian women. Fifteen (15) cases of pregnancy granuloma or 'epulis gravidanum' were found. Of these subjects, 287 representing 71.8 percent were on birth control before conception, while 113 or 28.2 percent were not. Nine (9) cases of pregnancy tumour were found in the group on birth control pills and six (6) in the group not on birth control representing an incidence of 3.1 and 5.3 percent respectively. Literature review indicate a general incidence of between 0-2.5 percent. Five of the granuloma regressed post partum, while ten were excised. Patients were followed 1-2 years post partum and no recurrence was recorded, even in patients who have re-commenced on contraceptives.

Influence of nitric oxide on histamine and carbachol-induced gastric Acid secretion in the common african toad - bufo regularis.

The study aimed to determine the influence of nitric oxide (NO) on the action of histamine and carbachol on acid secretion in the common African toad - Bufo regularis. Gastric acidity was determined by titration method. The acid secretion was determined when nitric oxide was absent following administration of NO synthase inhibitor; N-nitro-L-arginine methyl ester (L-NAME) and when nitric oxide was in excess by administration of exogenous NO donor, sodium nitroprusside (SNP). Histamine or carbachol increased acid secretion in the toad. Acid output increased from 0.32 +/- 0.04 mEq/15min to 0.56 +/- 0.08 and 0.61 +/- 0.05 mEq/15min for histamine and carbachol respectively [P < 0.05]. Pretreatment of the toad with L-NAME produced further increases in histamine (0.62 +/- 0.06 mEq/15min) or carbachol (0.74 +/- 0.06 mEq/15min) induced acid secretion respectively. SNP however, completely abolished the acid secretion stimulated by either histamine or carbachol. It was therefore concluded that nitric oxide has a negative influence on the histamine or carbachol-stimulated acid secretion in the toad - Bufo regularis.

Molecular cloning, characterization, and expression in Escherichia coli of full-length cDNAs of three human glutathione S-transferase Pi gene variants. Evidence for differential catalytic activity of the encoded proteins.

We report the isolation of three full-length cDNAs corresponding to the mRNAs of closely related glutathione S-transferase (GST) Pi genes, designated hGSTP1*A, hGSTP1*B, and hGSTP1*C, expressed in normal cells and malignant gliomas. The variant cDNAs result from A --> G and C --> T transitions at nucleotides +313 and +341, respectively. The transitions changed codon 104 from ATC (Ile) in hGSTP1*A to GTC (Val) in hGSTP1*B and hGSTP1*C and changed codon 113 from GCG (Ala) to GTG (Val) in hGSTP1*C. Both amino changes are in the electrophile-binding active site of the GST Pi peptide. Computer modeling of the deduced crystal structures of the encoded peptides showed significant deviations in the interatomic distances of critical electrophile-binding active site amino acids as a consequence of the amino acid changes. The encoded proteins expressed in Escherichia coli and purified by GSH affinity chromatography showed a 3-fold lower Km (CDNB) and a 3-4-fold higher Kcat/Km for the hGSTP1*A encoded protein than the proteins encoded by hGSTP1*B and hGSTP1*C. Analysis of 75 cases showed the relative frequency of hGSTP1*C to be 4-fold higher in malignant gliomas than in normal tissues. These data provide conclusive molecular evidence of allelopolymorphism of the human GST Pi gene locus, resulting in active, functionally different GST Pi proteins, and should facilitate studies of the role of this gene in xenobiotic metabolism, cancer, and other human diseases.