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1.
PLoS One ; 19(2): e0298752, 2024.
Article in English | MEDLINE | ID: mdl-38416754

ABSTRACT

INTRODUCTION: This study investigated the interactions between a low protein high calorie (LPHC) diet and an integrase inhibitor-containing antiretroviral drug regimen (INI-CR)in light of evidence suggesting that the initiation of cART in patients with poor nutritional status is a predictor of mortality independent of immune status. METHODS: Freshly weaned Sprague Dawley rats (120) were randomized into the standard, LPHC and normal protein high calorie (NPHC) diet groups (n = 40/group) initially for 15 weeks. Thereafter, experimental animals in each diet group were further randomized into four treatment sub-groups (n = 10/group) Control (normal saline), group 1(TDF+3TC+DTG and Tesamorelin), group 2 (TDF+3TC+DTG), and Positive control (AZT+3TC+ATV/r) with treatment and diets combined for 9 weeks. Weekly body weights, fasting blood glucose (FBG), oral glucose tolerance test (OGTT); lipid profiles, liver weights, hepatic triglycerides and adiposity were assessed at week 24. RESULTS: At week 15, body weights increased between the diet group in phase 1(standard 146 ± 1.64 vs. 273.1 ± 1.56 g), (NPHC, 143.5 ± 2.40 vs. 390.2 ± 4.94 g) and (LPHC, 145.5 ± 2.28 g vs. 398.3 ± 4.89 g) (p< 0.0001). A similar increase was noted in the FBG and OGTT (p< 0.0001). In phase 2, there was an increase in FBG, OGTT, body weights, lipid profile, liver weights, hepatic triglycerides, adiposity and insulin levels in group 2 and positive control in both NPHC and LPHC diet groups (p<0.0001). Growth hormone levels were decreased in Tesamorelin-free group 2 and positive control in both NPHC and LPHC (p< 0.0001). CONCLUSIONS: The obesogenic activities of the LPHC diet exceeded that of the NPHC diet and interacted with both integrase-containing and classical cART drug regimens to reproduce cART associated metabolic dysregulation. The effects were however reversed by co-administration with tesamorelin, a synthetic growth hormone releasing hormone analogue.


Subject(s)
HIV Infections , Metabolic Syndrome , Humans , Rats , Animals , Rats, Sprague-Dawley , Obesity , Diet, Protein-Restricted , HIV Infections/drug therapy , Triglycerides , Lipids/therapeutic use
2.
Account Res ; 30(6): 343-355, 2023 12.
Article in English | MEDLINE | ID: mdl-34620012

ABSTRACT

Academic medical centers conduct clinical research and provide patient care to the community and their workforce. Conflict may exist, as employees might expect benefits or feel pressured or coerced to participate in research studies or receive clinical care. Without evidence, some universities consider employees to be part of a vulnerable population for research consent at their institution, potentially restricting opportunities for employees to participate in clinical trials. At the same time, these universities encourage employees to receive health care at the same institution. We hypothesized that attitudes toward voluntary research participation and receipt of health care services at the site of employment are similar and favorable. To study this, we conducted a survey of employees at Oregon Health & Science University (OHSU) that asked parallel questions focusing on attitudes regarding concerns with participation in research and receipt of clinical care. We found the majority of respondents reported favorable and similar attitudes regarding employee participation in clinical care 596/688 (87%) or research 605/639 (95%) and personally comfortable with the idea (614/688 (90%) for clinical care, 582/639 (92%) for research participation). Our findings support efforts to remove barriers that restrict participation in clinical research by employees at academic medical centers.


Subject(s)
Attitude , Employment , Humans , Universities , Oregon , Surveys and Questionnaires
3.
Sci Rep ; 11(1): 21513, 2021 11 02.
Article in English | MEDLINE | ID: mdl-34728706

ABSTRACT

Short-term reattendances to emergency departments are a key quality of care indicator. Identifying patients at increased risk of early reattendance could help reduce the number of missed critical illnesses and could reduce avoidable utilization of emergency departments by enabling targeted post-discharge intervention. In this manuscript, we present a retrospective, single-centre study where we created and evaluated an extreme gradient boosting decision tree model trained to identify patients at risk of reattendance within 72 h of discharge from an emergency department (University Hospitals Southampton Foundation Trust, UK). Our model was trained using 35,447 attendances by 28,945 patients and evaluated on a hold-out test set featuring 8847 attendances by 7237 patients. The set of attendances from a given patient appeared exclusively in either the training or the test set. Our model was trained using both visit level variables (e.g., vital signs, arrival mode, and chief complaint) and a set of variables available in a patients electronic patient record, such as age and any recorded medical conditions. On the hold-out test set, our highest performing model obtained an AUROC of 0.747 (95% CI 0.722-0.773) and an average precision of 0.233 (95% CI 0.194-0.277). These results demonstrate that machine-learning models can be used to classify patients, with moderate performance, into low and high-risk groups for reattendance. We explained our models predictions using SHAP values, a concept developed from coalitional game theory, capable of explaining predictions at an attendance level. We demonstrated how clustering techniques (the UMAP algorithm) can be used to investigate the different sub-groups of explanations present in our patient cohort.


Subject(s)
Algorithms , Critical Illness/therapy , Emergency Service, Hospital/organization & administration , Hospitalization/statistics & numerical data , Machine Learning , Patient Discharge/statistics & numerical data , Patient Readmission/statistics & numerical data , Adolescent , Adult , Aftercare/statistics & numerical data , Aged , Electronic Health Records , Female , Humans , Male , Middle Aged , Retrospective Studies , Risk Factors , Triage , Young Adult
4.
Plant Methods ; 17(1): 80, 2021 Jul 21.
Article in English | MEDLINE | ID: mdl-34289852

ABSTRACT

BACKGROUND: The parasitic plant Orobanche cumana is one of the most important threats to sunflower crops in Europe. Resistant sunflower varieties have been developed, but new O. cumana races have evolved and have overcome introgressed resistance genes, leading to the recurrent need for new resistance methods. Screening for resistance requires the phenotyping of thousands of sunflower plants to various O. cumana races. Most phenotyping experiments have been performed in fields at the later stage of the interaction, requiring time and space. A rapid phenotyping screening method under controlled conditions would need less space and would allow screening for resistance of many sunflower genotypes. Our study proposes a phenotyping tool for the sunflower/O. cumana interaction under controlled conditions through image analysis for broomrape tubercle analysis at early stages of the interaction. RESULTS: We optimized the phenotyping of sunflower/O. cumana interactions by using rhizotrons (transparent Plexiglas boxes) in a growth chamber to control culture conditions and Orobanche inoculum. We used a Raspberry Pi computer with a picamera for acquiring images of inoculated sunflower roots 3 weeks post inoculation. We set up a macro using ImageJ free software for the automatic counting of the number of tubercles. This phenotyping tool was named RhizOSun. We evaluated five sunflower genotypes inoculated with two O. cumana races and showed that automatic counting of the number of tubercles using RhizOSun was highly correlated with manual time-consuming counting and could be efficiently used for screening sunflower genotypes at the tubercle stage. CONCLUSION: This method is rapid, accurate and low-cost. It allows rapid imaging of numerous rhizotrons over time, and it enables image tracking of all the data with time kinetics. This paves the way toward automatization of phenotyping in rhizotrons that could be used for other root phenotyping, such as symbiotic nodules on legumes.

5.
Prog Urol ; 31(16): 1093-1100, 2021 Dec.
Article in French | MEDLINE | ID: mdl-34272179

ABSTRACT

OBJECTIVE: The aim of this study was to report our experience after 10 years of practice of feminizing genitoplasty in prepubertal and adolescent patients with disorders of sex development (DSD) assigned females as females in a developing country. METHODOLOGY: This was a cross-sectional, descriptive and retrospective study over a period of 9 years. All pre-pubertal (8-12 years) and adolescent patients female sex assigned with DSD who had willfully consented to the surgery with their guardians and underwent feminizing genital surgery were enrolled in the study. Data collection included: age at presentation, precise diagnosis, surgical procedures, complications, cosmetic result and duration of follow-up. Each patient had a precise diagnosis and the surgery was planned after discussion with the multidisciplinary team. Cosmetic results were assessed based on: appearance of the clitoris and separation of the vaginal and urethral openings. RESULTS: Nine patients raised as females with a median age of 8 years (IR: 10.75) were recorded. Surgery was performed at a median age of 11 years (IR: 9.5). In this series, 6 had a 46, XY karyotype with varying diagnoses: partial androgen insensitivity syndrome (n=2); 5-alphareductase insufficiency (n=2); 17-ketoreductase insufficiency (n=2); gonadal dysgenesis with a mutation in the NR5A1 gene (n=2), 2 had ovostesticular DSD, (karyotypes 46, XX), and 1 had mixed gonadal dysgenesis (karyotype 45, X/46, XY). Partial or total gonad(s) removal in accordance with assigned gender was the most common associated procedure. It was bilateral in 7 cases and unilateral in 2 cases. Follow-up ranged from 3 months to 4.5 years (median: 26 months, IR:18.25). One patient had acute urinary retention in the early follow-up. No other complication such as incision bleeding was recorded. The cosmetic appearance of the external genitalia was satisfactory in all patients. CONCLUSION: Feminizing genital surgery in Cameroon remains a major challenge and should seldom be realized without a precise diagnosis. Late age at presentation is peculiar to our setting; however, it gives room for the patients' participation and input to decisions that will have a life-long personal impact on their lives in terms of psychosocial development and fertility. LEVEL OF EVIDENCE: 3.


Subject(s)
Disorders of Sex Development , Urogenital Surgical Procedures , Adolescent , Cameroon , Child , Cross-Sectional Studies , Female , Humans , Male , Retrospective Studies , Vagina
6.
Microorganisms ; 9(6)2021 Jun 21.
Article in English | MEDLINE | ID: mdl-34205811

ABSTRACT

There are well documented complications associated with the continuous use of antibiotics in the poultry industry. Over the past few decades, probiotics have emerged as viable alternatives to antibiotics; however, most of these candidate probiotic microorganisms have not been fully evaluated for their effectiveness as potential probiotics for poultry. Recent evaluation of a metagenome of broiler chickens in our laboratory revealed a prevalence of Lactobacillus reuteri (L. reuteri) and Actinobacteria class of bacteria in their gastrointestinal tract. In this study Lactobacillus reuteri and Streptomyces coelicolor (S. coelicolor) were selected as probiotic bacteria, encapsulated, and added into broiler feed at a concentration of 100 mg/kg of feed. In an 8-week study, 240 one day-old chicks were randomly assigned to four dietary treatments. Three dietary treatments contained two probiotic bacteria in three different proportions (L. reuteri and S. coelicolor individually at 100 ppm, and mixture of L. reuteri and S. coelicolor at 50 ppm each). The fourth treatment had no probiotic bacteria and it functioned as the control diet. L. reuteri and S. coelicolor were added to the feed by using wheat middlings as a carrier at a concentration of 100 ppm (100 mg/kg). Chickens fed diets containing L. reuteri and S. coelicolor mixture showed 2% improvement in body weight gain, 7% decrease in feed consumption, and 6-7% decrease in feed conversion ratios. This research suggests that L. reuteri and S. coelicolor have the potential to constitute probiotics in chickens combined or separately, depending on the desired selection of performance index.

7.
Heliyon ; 7(2): e06073, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33604468

ABSTRACT

In this work, the adsorption-desorption dynamics of diuron in three typical Kenyan agricultural soils, Nzoia (NZ), Thika (TH) and Machakos (MK) was investigated. The equilibrium adsorption data, tested against three classical nonlinear adsorption isotherms, was best described by the Freundlich model. The Freundlich adsorption constant, (KF), increased in the order MK > TH > NZ soil. Additionally, the negative Gibb's free energy values indicate the adsorption processes were thermodynamically spontaneous and physical. Multiple linear regression analysis indicated that the adsorption-desorption behavior was controlled by the clay and phosphorus contents of the soil. Phosphorus negatively affected the adsorption of diuron and promoted desorption. The groundwater ubiquity score (GUS) indicated that diuron movement rating in MK soil was 'moderate' while the movement in TH and NZ soils was 'high'.

8.
Anat Histol Embryol ; 50(1): 169-174, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32969516

ABSTRACT

Slight changes in lung volume have previously been reported in ducks. We studied the functional structure of the lung of the domestic duck using classical anatomical techniques as well as ultrasound monitoring to unravel the causes of such changes. Later dorsal and medioventral secondary bronchi were superficially positioned and covered with a thin transparent and collapsible membrane, internally lined with a cuboidal to squamous epithelium. The lung parenchyma was rigid, with atria well supported by septa containing smooth muscles, interparabronchial septa reinforced by collagen fibres, and blood capillaries supported by epithelial plates. On ultrasound monitoring, an outward and inward movement of the lung surface during inspiration and expiration, respectively, was evident at the region where the airways were covered by the thin membranes. The movements plausibly facilitated air movement in the lung just like the air sacs. We conclude that volume changes in the duck lung occur due to a slight morphological adaptation rather than a change in the archetypical design of the avian lung parenchyma.


Subject(s)
Ducks/anatomy & histology , Lung/anatomy & histology , Parenchymal Tissue/anatomy & histology , Air Sacs/anatomy & histology , Animals , Bronchi/anatomy & histology
9.
Int J Mol Sci ; 21(16)2020 Aug 05.
Article in English | MEDLINE | ID: mdl-32764289

ABSTRACT

Amino acids are known to play a key role in gene expression regulation. Amino acid signaling is mediated via two pathways: the mammalian target of rapamycin complex 1 (mTORC1) and the amino acid responsive (AAR) pathways. Cationic amino acid transporters (CATs) are crucial in these pathways due to their sensing, signaling and transport functions. The availability of certain amino acids plays a key role in the intake of other amino acids, hence affecting growth in young birds. However, the specific mechanism for regulating lysine transport for growth is not clear. In this study, we analyze the transcriptome profiles and mRNA expression of selected cationic amino acid transporters in the livers of broilers fed low and high lysine diets. Birds consumed high-lysine (1.42% lysine) or low-lysine (0.85% lysine) diets while the control group consumed 1.14% lysine diet. These concentrations of lysine represent 125% (high lysine), 75% (low lysine) and 100% (control), respectively, of the National Research Council's (NRC) recommendation for broiler chickens. After comparing the two groups, 210 differentially expressed genes (DEGs) were identified (fold change >1 and false discovery rate (FDR) <0.05). When comparing the high lysine and the low lysine treatments, there were 67 upregulated genes and 143 downregulated genes among these DEGs. Analysis of Kyoto Encyclopedia of Genes and Genomes (KEGG) and the Gene Ontology (GO) enrichment analysis show that cellular growth, lipid metabolism and lysine metabolism pathways were among the significantly enriched pathways. This study contributes to a better understanding of the potential molecular mechanisms underlying the correlation between lysine intake, body weight gain (BWG) and feed intake (FI) in broiler chickens. Moreover, the DEGs obtained in this study may be used as potential candidate genes for further investigation of broiler growth customized responses to individualized nutrients such as amino acids.


Subject(s)
Animal Feed , Chickens/genetics , Liver/metabolism , Transcriptome/genetics , Amino Acid Transport Systems, Basic , Animals , Chickens/growth & development , Diet , Gene Expression Profiling/methods , Gene Expression Regulation/genetics , Liver/growth & development , Lysine/pharmacology
10.
Int. j. morphol ; 38(4): 940-946, Aug. 2020. tab, graf
Article in English | LILACS | ID: biblio-1124880

ABSTRACT

Solanum nigrum (SLN), commonly known as African nightshade, is used as a vegetable as well as in the management and treatment of various ailments including gastric ulcers. We analyzed, both grossly and microscopically using H&E, Masson's trichrome and PSA staining methods, the protective effects of aqueous leaf extracts of three Kenyan SLN genotypes namely S. scabrum (SSB), S. sarrachoides (SSR) and S. villosum (SVL) on ethanol-induced gastric lesions in rats. There was evidence of gastro-protection by all the three genotypes with the SSB showing the highest ulcer inhibition score (76.37 %) followed by SSR (72.51 %) and SVL (63.30 %). SLN-pretreated rats showed less areas of gastric mucosal surface erosion. Additionally in the pretreated animals, the depth of the ulcers were markedly reduced, reaching only the gastric pit region except in those treated with SVL where the ulcers penetrated slightly more deeply to affect the gastric glands. Compared with controls, the mean microscopic ulcer index decreased 5.07, 3.55 and 2.37-fold in rats pretreated with SSB, SSR and SVL extracts respectively. Results of this work show extracts of the three SLN genotypes to have antiulcerogenic potential but at varied strengths, thus confirming earlier reports that phytoconstituents and hence the efficacy of a medicinal plant may be influenced by genetic factors.


Solanum nigrum (SLN), comúnmente conocida como la solanácea africana, se usa como vegetal, para el tratamiento de diversas dolencias incluyendo las úlceras gástricas. Analizamos de forma macro y microscópica, de forma macroscópica y microscópica, utilizando para ello tinciones de H&E, tricrómico de Masson y PSA los efectos protectores de extractos acuosos de hojas de tres genotipos SLN de Kenia: S. scabrum (SSB), S. sarrachoides (SSR) and S. villosum (SVL) en lesiones gástricas inducidas por etanol en ratas. Hubo evidencia de gastroprotección por parte de los tres genotipos con el SSB mostrando el puntaje más alto de inhibición de la úlcera (76,37 %) seguido de SSR (72,51 %) y SVL (63,30 %). Las ratas tratadas previamente con SLN mostraron menos áreas de erosión de la superficie de la mucosa gástrica. Además, en los animales pretratados, la profundidad de las úlceras se redujo notablemente, llegando solo a la región del fondo gástrico, excepto en aquellos tratados con SVL donde las úlceras penetraron un poco más profundamente para afectar las glándulas gástricas. En comparación con los controles, el índice medio de úlcera microscópica disminuyó 5,07, 3,55 y 2,37 veces en ratas pretratadas con extractos de SSB, SSR y SVL, respectivamente. Los resultados de este trabajo muestran que los extractos de los tres genotipos de SLN tienen potencial antiulcerogénico en diferentes concentraciones, lo que confirma informes anteriores que los fitoconstituyentes y la eficacia de una planta medicinal pueden estar influenciados por factores genéticos.


Subject(s)
Animals , Rats , Stomach Ulcer/drug therapy , Plant Extracts/therapeutic use , Solanum nigrum/chemistry , Anti-Ulcer Agents/therapeutic use , Stomach/drug effects , Rats, Wistar , Protective Agents , Plant Preparations/pharmacology , Kenya , Anti-Ulcer Agents/pharmacology
11.
Rev. med. vet. (Bogota) ; (40): 45-59, ene.-jun. 2020. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1139284

ABSTRACT

Abstract Seroprevalence of the antibodies of Brucella canis and Brucella abortus in dogs was assessed using a cross-sectional survey in Anambra and Enugu States, Nigeria. A total of 123 Companion dogs made up of 65 clinic dogs, 34 slaughter dogs and 24 household dogs were screened. For B. abortus antibody assay, the collected serum was used for Rose Bengal plate test (RBPT), Serum agglutination test (SAT) and Solid Phase Immunoassay technique with Immunocomb® Canine Brucellosis Antibody Test Kit was used. Out of the 123 dogs screened, none was positive for Brucella abortus antibodies while 34 (27.7%) of the dogs screened were positive for B. canis antibodies. There was a significant association (P<0.05) between infection and sex, the infection was significantly higher (P<0.05) in female than male dogs. Prevalence was significantly higher (P<0.05) in Exotic breeds than in mixed and local dog breeds. There was no association (P>0.05) between infection and antibody titre levels in the different categories of dogs. However, there was significant association (P<0.05) between the presence of Brucella canis antibodies and free roaming of dogs. This study provides the first serological evidence of B. canis infection in dogs in Enugu and Anambra States. This shows that B. canis is endemic in both states, underscoring the need for further studies. Female dogs, exotic breeds and freely roaming dogs are at a higher risk of Brucella infection in the study area; therefore, preventive and control measures are strongly recommended.


Resumen Se evaluó la seroprevalencia de los anticuerpos de Brucella canis y Brucella abortus en perros usando un sondeo transversal en los Estados Anambra and Enugu, Nigeria. Se examinó un total de 123 perros de compañía, de los cuales 65 eran perros de clínica, 34 perros de matadero y 24 perros caseros. Para el ensayo de anticuerpos de B. abortus, el suero muestreado se usó para la prueba de Rosa de Bengala (RBPT), prueba de aglutinación del suero (SAT) y se usó la técnica de inmunoensayo en fase sólida con el kit de prueba de anticuerpos para brucelosis canina Immunocomb®. De los 123 perros analizados, ninguno dio positivo para los anticuerpos de Brucella abortus mientras que 34 (27.7%) de los perros analizados dieron positivo para los anticuerpos de B. canis. Hubo una asociación significativa (P<0.05) entre infección y género; la infección fue significativamente más alta (P<0.05) en las hembras que en los machos. La prevalencia fue significativamente más alta (P<0.05) en las razas exóticas que en las razas cruzadas y las razas locales. No hubo ninguna relación (P>0.05) entre la infección y los niveles de titulación de anticuerpos en las diferentes categorías de perros. Sin embargo, hubo una relación significativa (P<0.05) entre la presencia de anticuerpos Brucella canis y los perros que andan libremente por doquier. Este estudio provee la primera evidencia serológica de infección con B. canis en perros de los Estados Enugu y Anambra. Esto muestra que la B. canis es endémica en ambos estados, enfatizando la necesidad de hacer más estudios. Las hembras, las razas exóticas y los animales que deambulan libremente se encuentran en el riesgo más alto de infección con Brucella en el área de estudio; por consiguiente, se recomienda enormemente tomar medidas preventivas y de control.

12.
Poult Sci ; 99(3): 1409-1420, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32115028

ABSTRACT

Lysine is the second most limiting amino acid after methionine and is considered the most limiting amino acid for growth in poultry. Lysine requirement for broiler chickens has changed over the years. Leptin and adiponectin represent 2 adipokines that mediate metabolism by eliciting satiety effects whereas ghrelin peptide hormone influences appetite. We hypothesize that this affects growth performance of chicks. This study evaluates the effect of varying dietary lysine homeostasis on performance of broiler chickens through satiety- and appetite-mediating hormones. In 3 replications, 270 one-day-old chicks were reared for 8 wk feeding on diets comprising 0.85, 1.14, and 1.42% lysine during the starter period and 0.75, 1.00, and 1.25% lysine during the grower period. These concentrations of lysine represent 75% (low lysine), 100% (control), and 125% (high lysine) of National Research Council recommendation for broiler chickens. Feed and water were provided for ad libitum consumption. At 8 wk of age, liver, pancreas, brain, and hypothalamus tissues were collected from 18 birds randomly selected from each treatment, snap frozen in liquid nitrogen, and stored at -80°C until use. Total RNA was extracted, and cDNA was synthesized for quantitative real-time PCR assays. Low lysine concentration caused slow growth and high mortality. There was significant upregulation of ghrelin in the hypothalamus and pancreas, and leptin and adiponectin in the hypothalamus and liver, and downregulation of ghrelin in the intestines. At low lysine concentrations, adiponectin was not expressed in both pancreas and intestines. High lysine concentration exhibited increased growth, upregulation of ghrelin in the liver, and downregulation of ghrelin in the intestines, and both adiponectin and leptin in the liver. The expression of ghrelin was negatively correlated with the expression of adiponectin and leptin (P < 0.05) in the liver, hypothalamus, and pancreas. Expression of leptin was positively correlated with adiponectin in the hypothalamus and liver (P < 0.05), exhibiting satiety effects when the concentrations of lysine were low.


Subject(s)
Appetite/genetics , Chickens/physiology , Lysine/metabolism , Neuropeptides/genetics , Peptide Hormones/genetics , Satiation , Adiponectin/genetics , Adiponectin/metabolism , Animal Feed/analysis , Animals , Chickens/genetics , Chickens/growth & development , Diet/veterinary , Dietary Supplements/analysis , Dose-Response Relationship, Drug , Down-Regulation , Gene Expression Profiling/veterinary , Ghrelin/genetics , Ghrelin/metabolism , Homeostasis , Leptin/genetics , Leptin/metabolism , Lysine/administration & dosage , Neuropeptides/metabolism , Peptide Hormones/metabolism , Random Allocation , Up-Regulation
13.
PLoS Negl Trop Dis ; 14(2): e0008088, 2020 02.
Article in English | MEDLINE | ID: mdl-32109246

ABSTRACT

BACKGROUND: Rabies lyssavirus (RABV) is the aetiologic agent of rabies, a disease that is severely underreported in Nigeria as well as elsewhere in Africa and Asia. Despite the role that rabies diagnosis plays towards elucidating the true burden of the disease, Nigeria-a country of 180 million inhabitants-has a limited number of diagnostic facilities. In this study, we sought to investigate two of the World Organization for Animal Health (OIE)-recommended diagnostic assays for rabies-viz; the direct fluorescent antibody test (DFA) and the direct rapid immunohistochemical test (dRIT) in terms of their relative suitability in resource-limited settings. Our primary considerations were (1) the financial feasibility for implementation and (2) the diagnostic efficacy. As a case study, we used suspect rabies samples from dog meat markets in Nigeria. METHODS/PRINCIPAL FINDINGS: By developing a simple simulation framework, we suggested that the assay with the lowest cost to implement and routinely use was the dRIT assay. The costs associated with the dRIT were lower in all simulated scenarios, irrespective of the number of samples tested per year. In addition to the cost analysis, the diagnostic efficacies of the two assays were evaluated. To do this, a cohort of DFA-positive and -negative samples collected from dog meat markets in Nigeria were initially diagnosed using the DFA in Nigeria and subsequently sent to South Africa for diagnostic confirmation. In South Africa, all the specimens were re-tested with the DFA, the dRIT and a quantitative real-time polymerase chain reaction (qRT-PCR). In our investigation, discrepancies were observed between the three diagnostic assays; with the incongruent results being resolved by means of confirmatory testing using the heminested reverse transcription polymerase reaction and sequencing to confirm that they were not contamination. CONCLUSIONS/SIGNIFICANCE: The data obtained from this study suggested that the dRIT was not only an effective diagnostic assay that could be used to routinely diagnose rabies, but that the assay was also the most cost-effective option among all of the OIE recommended methods. In addition, the results of our investigation confirmed that some of the dogs slaughtered in dog markets were rabies-positive and that the markets posed a potential public health threat. Lastly, our data showed that the DFA, although regarded as the gold standard test for rabies, has some limitations-particularly at low antigen levels. Based on the results reported here and the current challenges faced in Nigeria, we believe that the dRIT assay would be the most suitable laboratory test for decentralized or confirmatory rabies diagnosis in Nigeria, given its relative speed, accuracy, cost and ease of use.


Subject(s)
Fluorescent Antibody Technique, Direct/veterinary , Immunohistochemistry/veterinary , Meat/virology , Rabies virus/isolation & purification , Rabies/veterinary , Animals , Antibodies, Viral/immunology , Costs and Cost Analysis , Diagnostic Tests, Routine/methods , Dog Diseases/virology , Dogs , Fluorescent Antibody Technique, Direct/economics , Fluorescent Antibody Technique, Direct/methods , Humans , Immunohistochemistry/economics , Immunohistochemistry/methods , Nigeria/epidemiology , Rabies/epidemiology , Sensitivity and Specificity
14.
Viruses ; 12(2)2020 01 23.
Article in English | MEDLINE | ID: mdl-31979379

ABSTRACT

Despite being the first country to register confirmed cases of Mokola and Lagos bat lyssaviruses (two very distant lyssaviruses), knowledge gaps, particularly on the molecular epidemiology of lyssaviruses, still exist in Nigeria. A total of 278 specimens were collected from dogs in southeastern Nigeria between October 2015 and July 2016, and 23 (8.3%) of these tested positive for lyssaviruses with the direct fluorescent antibody test (DFA). The lyssaviruses were genetically characterized by amplifying the highly conserved nucleoprotein (N) gene of the rabies lyssaviruses (RABVs) of the viral genome. Phylogenetic analyses of the nucleotide sequences showed that all the RABV sequences in this study were of the Africa-2 lineage. Our results demonstrated that transboundary transmission of rabies lyssavirus is a key event, given that one of the RABV sequences (MN196576) clustered with rabies variants from neighboring Niger Republic. Furthermore, three RABVs from dogs from Anambra State clustered separately forming a novel and distinct group. Our results demonstrated that transboundary transmission of RABLVs is a key driver in the spread of rabies in West Africa. In order for the successful control of this zoonotic disease, a multinational stepwise surveillance and elimination of rabies in Africa by 2030 is probably the solution for regional elimination.


Subject(s)
Dogs/virology , Nucleocapsid Proteins/genetics , Rabies virus/isolation & purification , Rabies/transmission , Rabies/veterinary , Africa, Western/epidemiology , Animals , Brain/virology , DNA, Viral/genetics , Nigeria/epidemiology , Phylogeny , Rabies/epidemiology , Rabies virus/classification
15.
Environ Monit Assess ; 192(1): 18, 2019 Dec 09.
Article in English | MEDLINE | ID: mdl-31820117

ABSTRACT

The occurrence of 17 antibiotics belonging to sulfonamides, ß-lactams, macrolides and aminoglycosides classes, and trimethoprim in raw hospital wastewater, wastewater treatment plant (WWTP), and surface water was determined. Residual antibiotics were quantified by LC/MS/MS. Residues of antibiotics in hospital wastewater were 3-10 times higher than that detected in WWTP and surface water. Trimethoprim, spectinomycin, ampicillin, and oxacillin were detected in all the sampled water. Sulfamethoxazole was detected at the highest concentration of 20.6, 7.8, and 6.8 µg L-1 in hospital wastewater, WWTP and in surface water, respectively. Other detected sulfonamides were sulfamethazine, sulfadiazine, and sulfanilamide at a concentration range of 0.4-15.7 µg L-1. Detected trimethoprim ranged from 0.4-6.6 µg L-1, the rest of the detected antibiotics were up to 1.0 µg L-1. The speciation of the sulfonamides at pH values relevant to sampled water was evaluated by use of pKa values. These compounds existed largely as anionic and neutral species indicating high mobility as these speciation forms are less sorbed in environmental matrices. Continuous monitoring of antibiotics residues in wastewater, surface water, and other environmental matrices is very important due to their adverse health and environmental effects. The information is useful in designing strategies for antibiotics pollution control and also in policy formulation.


Subject(s)
Anti-Bacterial Agents/analysis , Environmental Monitoring , Waste Disposal, Fluid , Water Pollutants, Chemical/analysis , Chromatography, Liquid , Fresh Water/chemistry , Kenya , Macrolides , Sulfonamides , Tandem Mass Spectrometry , Wastewater/chemistry , Water
16.
BMC Res Notes ; 11(1): 920, 2018 Dec 22.
Article in English | MEDLINE | ID: mdl-30577868

ABSTRACT

OBJECTIVES: Domestic dogs are the main reservoir of rabies virus (RABV) infection in Nigeria, thus surveillance of rabies in dog populations is crucial in order to understand the patterns of spread of infection and ultimately devise an appropriate rabies control strategy. This study determined the presence of lyssavirus antigen in brain tissues and anti-rabies antibodies in sera of apparently healthy and suspected-rabid dogs slaughtered for human consumption at local markets in South-Eastern Nigeria. RESULTS: Our findings demonstrated that 8.3% (n = 23) of brain tissues were lyssavirus positive and 2.5% (n = 25) of sera had rabies antibody levels as percentage blocking of 70% and above correlating with a cut-off value ≥ 0.5 IU/mL in the fluorescent antibody neutralization test. There was an inverse correlation between lyssavirus positivity and rabies antibody levels confirming that infected individuals most often do not develop virus neutralizing antibodies to the disease. The low percentage of rabies antibodies in this dog population suggests a susceptible population at high risk to RABV infection. These findings highlight a huge challenge to national rabies programs and subsequent elimination of the disease from Nigeria, considering that majority of dogs are confined to rural communal areas, where parenteral dog vaccination is not routinely undertaken.


Subject(s)
Antibodies, Viral/blood , Antigens, Viral/immunology , Dog Diseases/immunology , Lyssavirus/immunology , Rabies/immunology , Animals , Brain/immunology , Dog Diseases/blood , Dog Diseases/epidemiology , Dogs , Nigeria/epidemiology , Rabies/blood , Rabies/epidemiology
17.
Chem Mater ; 28(8): 2557-2572, 2016 Apr 26.
Article in English | MEDLINE | ID: mdl-27212791

ABSTRACT

The failure mechanism of silicon-based electrodes has been studied only in a half-cell configuration so far. Here, a combination of 7Li, 19F MAS NMR, XPS, TOF-SIMS, and STEM-EELS, provides an in-depth characterization of the solid electrolyte interphase (SEI) formation on the surface of silicon and its evolution upon aging and cycling with LiNi1/3Mn1/3Co1/3O2 as the positive electrode in a full Li-ion cell configuration. This multiprobe approach indicates that the electrolyte degradation process observed in the case of full Li-ion cells exhibits many similarities to what has been observed in the case of half-cells in previous works, in particular during the early stages of the cycling. Like in the case of Si/Li half-cells, the development of the inorganic part of the SEI mostly occurs during the early stage of cycling while an incessant degradation of the organic solvents of the electrolyte occurs upon cycling. However, for extended cycling, all the lithium available for cycling is consumed because of parasitic reactions and is either trapped in an intermediate part of the SEI or in the electrolyte. This nevertheless does not prevent the further degradation of the organic electrolyte solvents, leading to the formation of lithium-free organic degradation products at the extreme surface of the SEI. At this point, without any available lithium left, the cell cannot function properly anymore. Cycled positive and negative electrodes do not show any sign of particles disconnection or clogging of their porosity by electrolyte degradation products and can still function in half-cell configuration. The failure mechanism for full Li-ion cells appears then very different from that known for half-cells and is clearly due to a lack of cyclable lithium because of parasitic reactions occurring before the accumulation of electrolyte degradation products clogs the porosity of the composite electrode or disconnects the active material particles.

18.
J Ethnopharmacol ; 179: 177-96, 2016 Feb 17.
Article in English | MEDLINE | ID: mdl-26721219

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Plants from Kenyan flora are traditionally used against many ailments, including cancer and related diseases. Cancer is characterized as a condition with complex signs and symptoms. Recently there are recommendations that ethnopharmacological usages such as immune and skin disorders, inflammatory, infectious, parasitic and viral diseases should be taken into account when selecting plants that treat cancer. AIM: The present study was aimed at investigating the cytotoxicity of a plethora of 145 plant parts from 91 medicinal plants, most of which are used in the management of cancer and related diseases by different communities in Kenya, against CCRF-CEM leukemia cell line. MATERIALS AND METHODS: Extracts from different plant parts (leaves, stems, stem bark, roots, root barks, aerial parts and whole herb) were obtained by cold percolation using different solvent systems, such as (1:1v/v) dichloromethane (CH2Cl2) and n-hexane (1), methanol (MeOH) and CH2Cl2 (2); neat MeOH (3), 5% H2O in MeOH (4) and with ethanol (EtOH, 5); their cytotoxicities were determined using the resazurin reduction assay against CCRF-CEM cells. RESULTS: At a single concentration of 10µg/mL, 12 out of 145 extracts exhibited more than 50% cell inhibition. These include samples from the root bark of Erythrina sacleuxii (extracted with 50% n-hexane-CH2Cl2), the leaves of Albizia gummifera, and Strychnos usambarensis, the stem bark of Zanthoxylum gilletii, Bridelia micrantha, Croton sylvaticus, and Albizia schimperiana; the root bark of Erythrina burttii and E. sacleuxii (extracted with 50% CH2Cl2-MeOH), the stem bark of B. micrantha and Z. gilletii (extracted using 5% MeOH-H2O) and from the berries of Solanum aculeastrum (extracted with neat EtOH). The EtOH extract of the berries of S. aculeastrum and A. schimperiana stem bark extract displayed the highest cytotoxicity towards leukemia CCRF-CEM cells, with IC50 values of 1.36 and 2.97µg/mL, respectively. Other extracts having good activities included the extracts of the stem barks of Z. gilletii and B. micrantha and leaves of S. usambarensis with IC50 values of 9.04, 9.43 and 11.09µg/mL, respectively. CONCLUSIONS: The results of this study provided information related to the possible use of some Kenyam medicinal plants, and mostly S. aculeastrum, A. schimperiana, C. sylvaticus, Z. gilletii, B. micrantha and S. usambarensis in the treatment of leukemia. The reported data helped to authenticate the claimed traditional use of these plants. However, most plants are used in combination as traditional herbal concoctions. Hence, the cytotoxicity of corresponding plant combinations should be tested in vitro to authenticate the traditional medical practitioners actual practices.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Growth Inhibitors/pharmacology , Leukemia/pathology , Plant Extracts/pharmacology , Plants, Medicinal , Cell Line, Tumor , Cell Survival/drug effects , Humans , Kenya
19.
Antimicrob Agents Chemother ; 60(1): 115-25, 2016 01.
Article in English | MEDLINE | ID: mdl-26459907

ABSTRACT

The heme-containing enzymes indoleamine 2,3-dioxygenase-1 (IDO-1) and IDO-2 catalyze the conversion of the essential amino acid tryptophan into kynurenine. Metabolites of the kynurenine pathway and IDO itself are involved in immunity and the pathology of several diseases, having either immunoregulatory or antimicrobial effects. IDO-1 plays a central role in the pathogenesis of cerebral malaria, which is the most severe and often fatal neurological complication of infection with Plasmodium falciparum. Mouse models are usually used to study the underlying pathophysiology. In this study, we screened a natural compound library against mouse IDO-1 and identified 8-aminobenzo[b]quinolizinium (compound 2c) to be an inhibitor of IDO-1 with potency at nanomolar concentrations (50% inhibitory concentration, 164 nM). Twenty-one structurally modified derivatives of compound 2c were synthesized for structure-activity relationship analyses. The compounds were found to be selective for IDO-1 over IDO-2. We therefore compared the roles of prominent amino acids in the catalytic mechanisms of the two isoenzymes via homology modeling, site-directed mutagenesis, and kinetic analyses. Notably, methionine 385 of IDO-2 was identified to interfere with the entrance of l-tryptophan to the active site of the enzyme, which explains the selectivity of the inhibitors. Most interestingly, several benzo[b]quinolizinium derivatives (6 compounds with 50% effective concentration values between 2.1 and 6.7 nM) were found to be highly effective against P. falciparum 3D7 blood stages in cell culture with a mechanism independent of IDO-1 inhibition. We believe that the class of compounds presented here has unique characteristics; it combines the inhibition of mammalian IDO-1 with strong antiparasitic activity, two features that offer potential for drug development.


Subject(s)
Antimalarials/pharmacology , Indoleamine-Pyrrole 2,3,-Dioxygenase/antagonists & inhibitors , Malaria/drug therapy , Plasmodium berghei/drug effects , Quinolizines/pharmacology , Animals , Antimalarials/chemical synthesis , Antimalarials/chemistry , Cell Line, Tumor , Cell Survival/drug effects , Cloning, Molecular , Crystallography, X-Ray , Erythrocytes/drug effects , Erythrocytes/parasitology , Escherichia coli/genetics , Escherichia coli/metabolism , Gene Expression , Humans , Indoleamine-Pyrrole 2,3,-Dioxygenase/chemistry , Indoleamine-Pyrrole 2,3,-Dioxygenase/genetics , Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism , Kynurenine/metabolism , Malaria/parasitology , Mice , Mutagenesis, Site-Directed , Plasmodium berghei/enzymology , Plasmodium berghei/genetics , Plasmodium falciparum/drug effects , Plasmodium falciparum/enzymology , Plasmodium falciparum/genetics , Quinolizines/chemical synthesis , Quinolizines/chemistry , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Structure-Activity Relationship , Tryptophan/antagonists & inhibitors , Tryptophan/metabolism
20.
J Biol Chem ; 290(49): 29629-41, 2015 Dec 04.
Article in English | MEDLINE | ID: mdl-26318454

ABSTRACT

The malaria parasite Plasmodium falciparum apicoplast indirect aminoacylation pathway utilizes a non-discriminating glutamyl-tRNA synthetase to synthesize Glu-tRNA(Gln) and a glutaminyl-tRNA amidotransferase to convert Glu-tRNA(Gln) to Gln-tRNA(Gln). Here, we show that Plasmodium falciparum and other apicomplexans possess a unique heterodimeric glutamyl-tRNA amidotransferase consisting of GatA and GatB subunits (GatAB). We localized the P. falciparum GatA and GatB subunits to the apicoplast in blood stage parasites and demonstrated that recombinant GatAB converts Glu-tRNA(Gln) to Gln-tRNA(Gln) in vitro. We demonstrate that the apicoplast GatAB-catalyzed reaction is essential to the parasite blood stages because we could not delete the Plasmodium berghei gene encoding GatA in blood stage parasites in vivo. A phylogenetic analysis placed the split between Plasmodium GatB, archaeal GatE, and bacterial GatB prior to the phylogenetic divide between bacteria and archaea. Moreover, Plasmodium GatA also appears to have emerged prior to the bacterial-archaeal phylogenetic divide. Thus, although GatAB is found in Plasmodium, it emerged prior to the phylogenetic separation of archaea and bacteria.


Subject(s)
Apicoplasts/metabolism , GATA Transcription Factors/metabolism , Nitrogenous Group Transferases/metabolism , Plasmodium falciparum/metabolism , Protozoan Proteins/metabolism , RNA, Transfer, Amino Acyl/biosynthesis , Antimalarials/chemistry , Cell Nucleus/metabolism , Computational Biology , Erythrocytes/parasitology , Gene Deletion , Green Fluorescent Proteins/metabolism , Humans , Malaria/metabolism , Malaria/parasitology , Models, Molecular , Phylogeny , Protein Structure, Tertiary , RNA, Transfer, Gln/genetics , Recombinant Proteins/metabolism
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