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1.
Trop Med Health ; 52(1): 72, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39425178

RESUMO

Malaria remains a key health and economic problem, particularly in sub-Saharan Africa. The emergence of artemisinin drug resistance (ART-R) parasite strains poses a serious threat to the control and elimination of this scourge. This is because artemisinin-based combination therapies (ACTs) remain the first-line treatment in the majority of malaria-endemic regions in Sub-Saharan Africa. Certain single-nucleotide polymorphisms in the propeller domains of Plasmodium falciparum Kelch 13 protein (K13) have been associated with delayed parasite clearance in vivo and in vitro. These mutations serve as vital molecular markers for tracking the emergence and dispersion of resistance. Recently, there have been increasing reports of the emergence and spread of P. falciparum ART-R parasites in the Eastern Africa region. This necessitates continued surveillance to best inform mitigation efforts. This study investigated the presence of all reported mutations of K13 propeller domains in the parasite population in Busia County, Kenya, a known malaria-endemic region. Two hundred twenty-six participants with microscopically confirmed uncomplicated malaria were recruited for this study. They were treated with artemether-lumefantrine under observation for the first dose, and microscopic examination was repeated 1 day later after ensuring the participants had taken the second and third doses. P. falciparum DNA from all samples underwent targeted amplification of the K13 gene using a semi-nested PCR approach, followed by Sanger sequencing. The recently validated ART-R K13 mutation C469Y was identified in three samples. These three samples were among 63 samples with a low reduction in parasitemia on day 1, suggesting day 1 parasitemia reduction rate is a useful parameter to enrich the ART-R parasites for further analysis. Our findings highlight the need for continuous surveillance of ART-R in western Kenya and the region to determine the spread of ART-R and inform containment.

2.
J Pharmacol Exp Ther ; 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39304350

RESUMO

Despite considerable efforts, there remains no FDA-approved medications for cocaine use disorder (CUD). One strategy to mitigate cocaine craving and relapse is to elevate dopamine (DA). The DA transport inhibitor and releaser d-amphetamine has been shown to decrease cocaine self-administration (SA), although it has abuse liability. Recently, several modafinil analogues reduced cocaine SA in rats and monkeys, including JJC8-088, characterized as "cocaine like" in rats, and JJC8-091, characterized as "atypical" and not SA by rats. The present studies evaluated the reinforcing effects of both compounds in monkeys under several conditions. For Experiment 1, four male cocaine-experienced rhesus monkeys self-administered cocaine (0.001-0.3 mg/kg/injection), JJC8-088 (0.001-0.3 mg/kg/injection), and JJC8-091 (0.1-3.0 mg/kg/injection) under a progressive-ratio (PR) schedule of reinforcement. Both JJC compounds functioned as reinforcers with equal reinforcing strength to cocaine. Although JJC8-091 was less potent than cocaine, JJC8-088 and cocaine had similar potencies. For Experiment 2, one male and two females drug-naïve cynomolgus monkeys responded on a fixed-ratio schedule of food reinforcement. JJC8-091 was self-administered at rates higher than saline in all three monkeys. In Experiment 3, monkeys from Experiment 2 responded under a concurrent drug vs. food choice paradigm and given access to cocaine or JJC8-091 under these conditions. At doses equal to or one-half log-units higher than doses used in Experiment 2, cocaine, but not JJC8-091, was chosen over food. Together, these results demonstrate that while JJC8-091 may be reinforcing under some conditions, its reinforcing strength, in the presence of an alternative reinforcer, is substantially less than cocaine. Significance Statement JJC8-088 and JJC8-091 have shown efficacy is reducing cocaine self-administration in rats and in nonhuman primates. This study found that both compounds maintained self-administration in monkeys responding under several conditions. However, when given access to an alternative reinforcer during the self-administration session, JJC8-091 was not reinforcing, suggesting that JJC8-091 may be a viable candidate for CUD since, in the human population, alternatives to drug use are often available.

3.
Trop Med Health ; 52(1): 52, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103954

RESUMO

BACKGROUND: While Plasmodium falciparum (Pf) stands out as the most lethal malaria parasite species in humans, the impact of other species should not be dismissed. Moreover, there is a notable lack of understanding of mixed-species infections and their clinical implications. METHODS: We conducted eight school-based cross-sectional malariometric surveys in the Lake Victoria region of western Kenya between January-February 2012 and September-October 2018. In each survey, a minimum of 100 children aged 3 to 15 years were randomly chosen from a school in Ungoye village on the mainland and as well as from each school selected in every catchment area on Mfangano island. Plasmodium infection was determined by microscopy and nested polymerase chain reaction (PCR). The multiple-kind lottery (MKL) model calculated the expected distribution of Plasmodium infections in the population and compared it to observed values using a chi-squared test (χ2). RESULTS: The Plasmodium prevalence was 25.9% (2521/9724) by microscopy and 51.1% (4969/9724) by PCR. Among all infections detected by PCR, Pf, P. malariae (Pm), and P. ovale (Po) mono-infections were 58.6%, 3.1%, and 1.8%, respectively. Pf/Pm, Pf/Po, Pm/Po, and Pf/Pm/Po co-infections were 23.5%, 4.3%, 0.1%, and 8.6%, respectively. MKL modelling revealed non-random distributions, with frequencies of Pf/Pm and Pf/Pm/Po co-infections being significantly higher than expected (χ2 = 3385.60, p < 0.001). Pf co-infections with Pm and Po were associated with a decreased risk of fever (aOR 0.64, 95% CI 0.46-0.83; p = 0.01) and increased risks of splenomegaly (aOR 12.79, 95% CI 9.69-16.9; p < 0.001) and anaemia (aOR 2.57, 95% CI 2.09-3.15; p < 0.001), compared to single-species infections. CONCLUSION: This study sheds light on the potential interaction between Pf and Pm and/or Po. Given the clinical significance of mixed-species infections, improved diagnostics, and case management of Pm and Po are urgently needed.

4.
Drug Metab Pharmacokinet ; 57: 101029, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39079373

RESUMO

Cytochrome P450 3A4 (CYP3A4) enzyme is involved in the metabolism of about 30 % of clinically used drugs, including the antimalarials artemether and lumefantrine. CYP3A4 polymorphisms yield enzymatic variants that contribute to inter-individual variation in drug metabolism. Here, we examined CYP3A4 polymorphisms in populations from malaria-endemic islands in Lake Victoria, Kenya, and Vanuatu, to expand on the limited data sets. We used archived dried blood spots collected from 142 Kenyan and 263 ni-Vanuatu adults during cross-sectional malaria surveys in 2013 and 2005-13, respectively, to detect CYP3A4 variation by polymerase chain reaction (PCR) and sequencing. In Kenya, we identified 14 CYP3A4 single nucleotide polymorphisms (SNPs), including the 4713G (CYP3A4∗1B; allele frequency 83.9 %) and 19382A (CYP3A4∗15; 0.7 %) variants that were previously linked to altered metabolism of antimalarials. In Vanuatu, we detected 15 SNPs, including the 4713A (CYP3A4∗1A; 88.6 %) and 25183C (CYP3A4∗18; 0.6 %) variants. Additionally, we detected a rare and novel SNP C4614T (0.8 %) in the 5' untranslated region. A higher proportion of CYP3A4 genetic variance was found among ni-Vanuatu populations (16 %) than among Lake Victoria Kenyan populations (8 %). Our work augments the scarce data sets and contributes to improved precision medicine approaches, particularly to anti-malarial chemotherapy, in East African and Pacific Islander populations.


Assuntos
Antimaláricos , Citocromo P-450 CYP3A , Malária , Polimorfismo de Nucleotídeo Único , Humanos , Quênia/epidemiologia , Polimorfismo de Nucleotídeo Único/genética , Malária/genética , Malária/tratamento farmacológico , Malária/epidemiologia , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Vanuatu/epidemiologia , Feminino , Adulto , Masculino , Doenças Endêmicas , Estudos Transversais , Variação Genética/genética
5.
PLoS Negl Trop Dis ; 18(7): e0012282, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38990839

RESUMO

OVERVIEW: The roadmap adopted by the World Health Organization (WHO) for eliminating neglected tropical diseases aims to eliminate schistosomiasis, as a public health concern, by 2030. While progress has been made towards reducing schistosomiasis morbidity control in several sub-Saharan African countries, there is still more that needs to be done. Proper surveillance using accurate diagnostics with acceptable sensitivity and specificity is essential for evaluating the success of all efforts against schistosomiasis. Microscopy, despite its low sensitivity, remains the gold standard approach for diagnosing the disease. Although many efforts have been made to develop new diagnostics based on circulating parasite proteins, genetic markers, schistosome egg morphology, and their paramagnetic properties, none has been robust enough to replace microscopy. This review highlights common diagnostic approaches for detecting schistosomiasis in field and clinical settings, major challenges, and provides new and novel opportunities and diagnosis pathways that will be critical in supporting elimination of schistosomiasis. METHODS: We searched for relevant and reliable published literature from PubMed, Scopus, google scholar, and Web of science. The search strategies were primarily determined by subtopic, and hence the following words were used (schistosom*, diagnosis, Kato-Katz, antibody test, circulating antigen, POC-CCA, UCP-LF-CAA, molecular diagnostics, nucleic acid amplification test, microfluidics, lab-on a disk, lab-on chip, recombinase polymerase amplification (RPA), LAMP, portable sequencer, nanobody test, identical multi-repeat sequences, diagnostic TPPs, REASSURED, extraction free), and Boolean operators AND and/OR were used to refine the searching capacity. Due to the global public health nature of schistosomiasis, we also searched for reliable documents, reports, and research papers published by international health organizations, World Health Organization (WHO), and Center for Disease control and Elimination.


Assuntos
Esquistossomose , Esquistossomose/diagnóstico , Esquistossomose/prevenção & controle , Humanos , Animais , Schistosoma/genética , Schistosoma/isolamento & purificação , Erradicação de Doenças , Sensibilidade e Especificidade , Técnicas de Diagnóstico Molecular/métodos , Doenças Negligenciadas/diagnóstico , Doenças Negligenciadas/prevenção & controle , Doenças Negligenciadas/parasitologia , Técnicas de Amplificação de Ácido Nucleico/métodos
6.
Ann Neurol ; 96(5): 914-931, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39073169

RESUMO

OBJECTIVE: Intellectual disability is often the outcome of neurodevelopmental disorders and is characterized by significant impairments in intellectual and adaptive functioning. X-linked intellectual disability (XLID) is a subset of these disorders caused by genetic defects on the X chromosome, affecting about 2 out of 1,000 males. In syndromic form, it leads to a broad range of cognitive, behavioral, ocular, and physical disabilities. METHODS: Employing exome or genome sequencing, here we identified 4 missense variants (c.475C > G; p.H159D, c.1373C > A; p.T458N, and c.1585G > A; p.E529K, c.953C > T; p.S318L) and a putative truncating variant (c.1413_1414del; p.Y471*) in the SRPK3 gene in 9 XLID patients from 5 unrelated families. To validate SRPK3 as a novel XLID gene, we established a knockout (KO) model of the SRPK3 orthologue in zebrafish. RESULTS: The 8 patients ascertained postnatally shared common clinical features including intellectual disability, agenesis of the corpus callosum, abnormal eye movement, and ataxia. A ninth case, ascertained prenatally, had a complex structural brain phenotype. Together, these data indicate a pathological role of SRPK3 in neurodevelopmental disorders. In post-fertilization day 5 larvae (free swimming stage), KO zebrafish exhibited severe deficits in eye movement and swim bladder inflation, mimicking uncontrolled ocular movement and physical clumsiness observed in human patients. In adult KO zebrafish, cerebellar agenesis and behavioral abnormalities were observed, recapitulating human phenotypes of cerebellar atrophy and intellectual disability. INTERPRETATION: Overall, these results suggest a crucial role of SRPK3 in the pathogenesis of syndromic X-linked intellectual disability and provide new insights into brain development, cognitive and ocular dysfunction in both humans and zebrafish. ANN NEUROL 2024;96:914-931.


Assuntos
Proteínas Serina-Treonina Quinases , Peixe-Zebra , Animais , Humanos , Masculino , Proteínas Serina-Treonina Quinases/genética , Feminino , Criança , Deficiência Intelectual/genética , Deficiência Intelectual Ligada ao Cromossomo X/genética , Pré-Escolar , Adolescente , Cognição/fisiologia , Adulto , Olho
7.
Addict Neurosci ; 112024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38911873

RESUMO

While the majority of people with cocaine use disorders (CUD) also co-use tobacco/nicotine, most preclinical cocaine research does not include nicotine. The present study examined nicotine and cocaine co-use under several conditions of intravenous drug self-administration in monkeys, as well as potential peripheral biomarkers associated with co-use. In Experiment 1, male rhesus monkeys (N = 3) self-administered cocaine (0.001-0.1 mg/kg/injection) alone and with nicotine (0.01-0.03 mg/kg/injection) under a progressive-ratio schedule of reinforcement. When nicotine was added to cocaine, there was a significant leftward/upward shift in the number of injections received. In Experiment 2, socially housed female and male cynomolgus monkeys (N = 14) self-administered cocaine under a concurrent drug-vs-food choice schedule of reinforcement. Adding nicotine to the cocaine solution shifted the cocaine dose-response curves to the left, with more robust shifts noted in the female animals. There was no evidence of social rank differences. To assess reinforcing strength, delays were added to the presentation of drug; the co-use of nicotine and cocaine required significantly longer delays to decrease drug choice, compared with cocaine alone. Blood samples obtained post-session were used to analyze concentrations of neuronally derived small extracellular vesicles (NDE); significant differences in NDE profile were observed for kappa-opioid receptors when nicotine and cocaine were co-used compared with each drug alone and controls. These results suggest that drug interactions involving the co-use of nicotine and cocaine are not simply changing potency, but rather resulting in changes in reinforcing strength that should be utilized to better understand the neuropharmacology of CUD and the evaluation of potential treatments.

8.
Immunity ; 57(8): 1769-1779.e4, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-38901428

RESUMO

Many infections, including malaria, are associated with an increase in autoantibodies (AAbs). Prior studies have reported an association between genetic markers of susceptibility to autoimmune disease and resistance to malaria, but the underlying mechanisms are unclear. Here, we performed a longitudinal study of children and adults (n = 602) in Mali and found that high levels of plasma AAbs before the malaria season independently predicted a reduced risk of clinical malaria in children during the ensuing malaria season. Baseline AAb seroprevalence increased with age and asymptomatic Plasmodium falciparum infection. We found that AAbs purified from the plasma of protected individuals inhibit the growth of blood-stage parasites and bind P. falciparum proteins that mediate parasite invasion. Protected individuals had higher plasma immunoglobulin G (IgG) reactivity against 33 of the 123 antigens assessed in an autoantigen microarray. This study provides evidence in support of the hypothesis that a propensity toward autoimmunity offers a survival advantage against malaria.


Assuntos
Autoanticorpos , Imunoglobulina G , Malária Falciparum , Plasmodium falciparum , Humanos , Plasmodium falciparum/imunologia , Autoanticorpos/imunologia , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Criança , Pré-Escolar , Adulto , Imunoglobulina G/imunologia , Imunoglobulina G/sangue , Feminino , Mali , Masculino , Adolescente , Anticorpos Antiprotozoários/imunologia , Estudos Longitudinais , Lactente , Antígenos de Protozoários/imunologia , Adulto Jovem , Autoantígenos/imunologia , Estudos Soroepidemiológicos , Pessoa de Meia-Idade
9.
Neuropsychopharmacology ; 49(11): 1729-1737, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38760425

RESUMO

Considerable research has suggested that certain cognitive domains may contribute to cocaine misuse. However, there are gaps in the literature regarding whether cognitive performance before drug exposure predicts susceptibility to cocaine self-administration and how cognitive performance relates to future cocaine intake. Thus, the present study aimed to examine cognitive performance, as measured using automated CANTAB cognitive battery, prior to and following acquisition of cocaine self-administration under a concurrent drug vs. food choice procedure in female and male socially housed cynomolgus macaques. The cognitive battery consisted of measures of associative learning (stimulus and compound discrimination tasks), behavioral flexibility (intradimensional and extradimensional tasks), and behavioral inhibition (stimulus discrimination reversal, SDR, and extra-dimensional reversal tasks). After assessing cognitive performance, monkeys were trained to self-administer cocaine (saline, 0.01-0.1 mg/kg/injection) under a concurrent cocaine vs. food schedule of reinforcement. After a history of cocaine self-administration across 3-4 years, the cognitive battery was re-assessed and compared with sensitivity to cocaine reinforcement. Results showed drug-naïve monkeys that were less accurate on the SDR task, measuring behavioral inhibition, were more sensitive to cocaine reinforcement under the concurrent cocaine vs. food choice procedure. Furthermore, following chronic cocaine self-administration, cocaine intake was a negative predictor of accuracy on the SDR behavioral inhibition task. After cocaine maintenance, monkeys with higher cocaine intakes required more trials to complete the SDR behavioral inhibition task and made more incorrect responses during these trials. No sex or social rank differences were noted. Overall, these findings suggest that cognitive performance may influence vulnerability to cocaine misuse. Also, chronic cocaine may decrease levels of behavioral inhibition as measured via the SDR task in both females and males.


Assuntos
Cocaína , Cognição , Macaca fascicularis , Autoadministração , Animais , Cocaína/administração & dosagem , Cocaína/farmacologia , Masculino , Feminino , Cognição/efeitos dos fármacos , Inibidores da Captação de Dopamina/administração & dosagem , Inibidores da Captação de Dopamina/farmacologia , Transtornos Relacionados ao Uso de Cocaína/psicologia , Fenótipo , Condicionamento Operante/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos
10.
Foot Ankle Orthop ; 9(2): 24730114241247821, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38711913
11.
PLoS One ; 19(4): e0298873, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38626173

RESUMO

Regular monitoring of bacterial susceptibility to antibiotics in clinical settings is key for ascertaining the current trends as well as re-establish empirical therapy. This study aimed to determine bacterial contaminants and their antimicrobial susceptibility patterns from medical equipment, inanimate surfaces and clinical samples obtained from Thika Level V Hospital (TLVH), Thika, in Central Kenya. Three hundred and five samples were collected between the period of March 2021 to November 2021 and comprised urine, pus swabs, catheter swabs, stool, and environmental samples. Bacterial identification and antimicrobial susceptibility were performed using VITEK 2 and disc diffusion respectively. We observed that Coagulase-negative Staphylococci (28 /160, 17.5%) were the most commonly isolated species from clinical samples followed by E. coli (22 /160 13.8%) and S. aureus (22/160, 13.8%). The bed rails were the mostly contaminated surface with S. aureus accounting for 14.2% (6/42). Among the clinical samples, pus swabs yielded the highest number of pathogens was pus (92/160). Trauma patients had the highest proportion of isolates (67/160, 41.8%). High level of antimicrobial resistance to key antimicrobials, particularly among Enterobacterales was observed. Extended Spectrum Beta Lactamase (ESBL) phenotype was noted in 65.9% (29/44) of enteric isolates. While further ESBL genetic confirmatory studies are needed, this study highlights the urgent need for actions that mitigate the spread of antibiotic-resistant bacteria.


Assuntos
Burkholderia cepacia , Stenotrophomonas maltophilia , Humanos , Escherichia coli , Farmacorresistência Bacteriana Múltipla , Staphylococcus aureus , Quênia , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Hospitais , Bactérias , Encaminhamento e Consulta , Supuração , beta-Lactamases
12.
Heliyon ; 10(6): e27344, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38533083

RESUMO

Background: Curable sexually transmitted infections (STIs), such as Neisseria gonorrhoeae (N. gonorrhoeae), are a major cause of poor pregnancy outcomes. The infection is often asymptomatic in pregnant women, and a syndrome-based approach of testing leads to a missed diagnosis. Culture followed by microscopy is inadequate and time-consuming. The gold standard nucleic acid amplification tests require advanced infrastructure settings, whereas point-of-care tests are limited to immunoassays with sensitivities and specificities insufficient to accurately diagnose asymptomatic cases. This necessitates the development and validation of assays that are fit for purpose. Methods: We identified new diagnostic target biomarker regions for N. gonorrhoeae using an algorithm for genome mining of identical multi-repeat sequences (IMRS). These were then developed as DNA amplification primers to design better diagnostic assays. To test the primer pair, genomic DNA was 10-fold serially diluted (100 pg/µL to 1 × 10-3 pg/µL) and used as DNA template for PCR reactions. The gold standard PCR using 16S rRNA primers was also run as a comparative test, and both assay products were resolved on 1% agarose gel. Results: Our newly developed N. gonorrhoeae IMRS-PCR assay had an analytical sensitivity of 6 fg/µL representing better sensitivity than the 16S rRNA PCR assay with an analytical sensitivity of 4.3096 pg/µL. The assay was also successfully validated using clinical urethral swab samples. We further advanced this technique by developing an isothermal IMRS, which was both reliable and sensitive for detecting cultured N. gonorrhoeae isolates at a concentration of 38 ng/µL. Combining isothermal IMRS with a low-cost lateral flow assay, we were able to detect N. gonorrhoeae amplicons at a starting concentration of 100 pg/µL. Conclusion: Therefore, there is a potential to implement this concept within miniaturized, isothermal, microfluidic platforms, and laboratory-on-a-chip diagnostic devices for highly reliable point-of-care testing.

13.
BMC Pregnancy Childbirth ; 24(1): 187, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459499

RESUMO

In sub-Saharan Africa, malaria, which remains a major public health burden, has a prevalence of 9 to 28% and malaria in pregnancy is associated with severe adverse outcomes for the mother and her baby. Here, we sought to determine the predictors of birth weight in a cohort of 140 women with malaria in pregnancy, who were recruited at the Webuye County hospital in Western Kenya. All study participants underwent malaria diagnosis through microscopic examination of blood smear samples and were grouped into the malaria-positive and malaria-negative groups. Both groups were followed up beginning at the first antenatal visit (March 2022) until delivery (December 2022) and various data, including demographic, parity, gravidity, socioeconomic, maternal and fetal outcomes were collected. Data analyses were done using SPSS version 27. Chi-square and Fisher's Exact tests were used for bivariate and relative risk analyses at a p-value of ≤0.05 (95%) confidence level. Most of the participants were aged 18-25 years, were primigravidas and married, had secondary school-level education, earned 20-30 thousand Kenya shillings, resided in rural areas, and were in the second trimester. There were 6 (4.6%) cases of low birth weight, 3 (4.5%) in the malaria-negative group and 3 (4.7%) in the malaria-positive group. During pregnancy, 41 (31.5%) were anaemic, 5 (3.8%) were HIV-positive, 5 (3.8%) had preeclampsia, and 2 (1.5%) had gestational diabetes. Our analyses show that confounding factors like anaemia, HIV, pre-eclampsia and gestational diabetes did not influence birthweight (p ≥ 0.923). The malaria-positive and malaria-negative groups did not differ significantly with regard to the low birth weight (relative risk: 0.999, 95% confidence interval: 0.926-1.077). Marital status, gestational age, and area of residence were associated with malaria p ≤ 0.001, ≤ 0.001 and 0.028 respectively. In both groups, 124 of the 140 deliveries had normal birth weights and of these 63 (95.4%, n = 70) were in the malaria-negative group, whereas 61 (95.3%, n = 70) belonged to the malaria-positive group.


Assuntos
Anemia , Diabetes Gestacional , Malária , Feminino , Gravidez , Humanos , Adolescente , Adulto Jovem , Adulto , Peso ao Nascer , Gestantes , Quênia/epidemiologia , Estudos Prospectivos , Malária/epidemiologia , Anemia/epidemiologia
14.
Front Immunol ; 15: 1352618, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38404581

RESUMO

Human malaria, caused by five Plasmodium species (P. falciparum, P. vivax, P. malariae, P. ovale, and P. knowlesi), remains a significant global health burden. While most interventions target P. falciparum, the species associated with high mortality rates and severe clinical symptoms, non-falciparum species exhibit different transmission dynamics, remain hugely neglected, and pose a significant challenge to malaria elimination efforts. Recent studies have reported the presence of antigens associated with cross-protective immunity, which can potentially disrupt the transmission of various Plasmodium species. With the sequencing of the Plasmodium genome and the development of immunoinformatic tools, in this study, we sought to exploit the evolutionary history of Plasmodium species to identify conserved cross-species B-cell linear epitopes in merozoite proteins. We retrieved Plasmodium proteomes associated with human malaria and applied a subtractive proteomics approach focusing on merozoite stage proteins. Bepipred 2.0 and Epidope were used to predict B-cell linear epitopes using P. falciparum as the reference species. The predictions were further compared against human and non-falciparum databases and their antigenicity, toxicity, and allergenicity assessed. Subsequently, epitope conservation was carried out using locally sequenced P. falciparum isolates from a malaria-endemic region in western Kenya (n=27) and Kenyan isolates from MalariaGEN version 6 (n=131). Finally, physiochemical characteristics and tertiary structure of the B-cell linear epitopes were determined. The analysis revealed eight epitopes that showed high similarity (70-100%) between falciparum and non-falciparum species. These epitopes were highly conserved when assessed across local isolates and those from the MalariaGEN database and showed desirable physiochemical properties. Our results show the presence of conserved cross-species B-cell linear epitopes that could aid in targeting multiple Plasmodium species. Nevertheless, validating their efficacy in-vitro and in-vivo experimentally is essential.


Assuntos
Malária Falciparum , Malária Vivax , Malária , Plasmodium , Animais , Humanos , Merozoítos , Epitopos de Linfócito B , Quênia , Proteômica , Plasmodium falciparum , Plasmodium vivax , Malária/diagnóstico
15.
J Leukoc Biol ; 115(4): 714-722, 2024 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-38169315

RESUMO

Rapid discrimination between viral and bacterial infections in a point-of-care setting will improve clinical outcome. Expression of CD64 on neutrophils (neuCD64) increases during bacterial infections, whereas expression of CD169 on classical monocytes (cmCD169) increases during viral infections. The diagnostic value of automated point-of-care neuCD64 and cmCD169 analysis was assessed for detecting bacterial and viral infections at the emergency department. Additionally, their value as input for machine learning models was studied. A prospective observational cohort study in patients suspected of infection was performed at an emergency department. A fully automated point-of-care flow cytometer measured neuCD64, cmCD169, and additional leukocyte surface markers. Flow cytometry data were gated using the FlowSOM algorithm. Bacterial and viral infections were assessed in standardized clinical care. The sole and combined diagnostic value of the markers was investigated. Clustering based on unsupervised machine learning identified unique patient clusters. Eighty-six patients were included. Thirty-five had a bacterial infection, 30 had a viral infection, and 21 had no infection. neuCD64 was increased in bacterial infections (P < 0.001), with an area under the receiver operating characteristic curve (AUROC) of 0.73. cmCD169 was higher in virally infected patients (P < 0.001; AUROC 0.79). Multivariate analyses incorporating additional markers increased the AUROC for bacterial and viral infections to 0.86 and 0.93, respectively. The additional clustering identified 4 distinctive patient clusters based on infection type and outcome. Automated neuCD64 and cmCD169 determination can discriminate between bacterial and viral infections. These markers can be determined within 30 min, allowing fast infection diagnostics in the acute clinical setting.


Assuntos
Infecções Bacterianas , Viroses , Humanos , Neutrófilos/metabolismo , Monócitos/metabolismo , Sistemas Automatizados de Assistência Junto ao Leito , Estudos Prospectivos , Biomarcadores/metabolismo , Viroses/diagnóstico , Infecções Bacterianas/microbiologia , Curva ROC , Serviço Hospitalar de Emergência , Receptores de IgG/metabolismo
16.
Psychopharmacology (Berl) ; 241(2): 263-274, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37882812

RESUMO

RATIONALE: Previous studies in socially housed monkeys examining acquisition of cocaine self-administration under fixed-ratio (FR) schedules of reinforcement found that subordinate males and dominant females were more vulnerable than their counterparts. OBJECTIVES: The present studies extended these findings in two ways: (1) to replicate the earlier study, in which female monkeys were studied after a relatively short period of social housing (~ 3 months) using cocaine-naïve female monkeys (n = 9; 4 dominant and 5 subordinate) living in well-established social groups (~ 18 months); and (2) in male monkeys (n = 3/social rank), we studied cocaine acquisition under a concurrent schedule, with an alternative, non-drug reinforcer available. RESULTS: In contrast to earlier findings, subordinate female monkeys acquired cocaine reinforcement (i.e., > saline reinforcement) at significantly lower cocaine doses compared with dominant monkeys. In the socially housed males, no dominant monkey acquired a cocaine preference (i.e., > 80% cocaine choice) over food, while two of three subordinate monkeys acquired cocaine reinforcement. In monkeys that did not acquire, the conditions were changed to an FR schedule with only cocaine available and after acquisition, returned to the concurrent schedule. In all monkeys, high doses of cocaine were chosen over food reinforcement. CONCLUSIONS: The behavioral data in females suggests that duration of social enrichment and stress can differentially impact vulnerability to cocaine reinforcement. The findings in socially housed male monkeys, using concurrent food vs. cocaine choice schedules of reinforcement, confirmed earlier social-rank differences using an FR schedule and showed that vulnerability could be modified by exposure to cocaine.


Assuntos
Cocaína , Habitação , Masculino , Feminino , Animais , Reforço Psicológico , Alimentos , Autoadministração , Esquema de Reforço , Relação Dose-Resposta a Droga
17.
OTA Int ; 6(5 Suppl): e291, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38152436

RESUMO

Objectives: The number of geriatric hip fracture patients is high and expected to rise in the coming years, and many are frail and at risk for adverse outcomes. Early identification of high-risk patients is crucial to balance treatment and optimize outcome, but remains challenging. Previous research in patients with multitrauma suggested that neutrophil phenotype analysis could aid in early identification of high-risk patients. This pilot study investigated the feasibility and clinical value of neutrophil phenotype analysis in geriatric patients with a hip fracture. Methods: A prospective study was conducted in a regional teaching hospital in the Netherlands. At the emergency department, blood samples were collected from geriatric patients with a hip fracture and analyzed using automated flow cytometry. Flow cytometry data were processed using an automated clustering algorithm. Neutrophil activation data were compared with a healthy control cohort. Neutrophil phenotype categories were assessed based on two-dimensional visual assessment of CD16/CD62L expression. Results: Blood samples from 45 geriatric patients with a hip fracture were included. Neutrophils showed an increased activation profile and decreased responsiveness to formyl peptides when compared to healthy controls. The neutrophil phenotype of all patients was categorized. The incidence of severe adverse outcome was significantly different between the different categories (P = 0.0331). Moreover, patients with neutrophil phenotype category 0 developed no severe adverse outcomes. Conclusions: Using point-of-care fully automated flow cytometry to analyze the neutrophil compartment in geriatric hip fracture patients is feasible and holds clinical value in determining patients at risk for adverse outcome. This study is a first step toward immuno-based precision medicine for identifying geriatric hip fracture patients that are deemed fit for surgery.

19.
Pathog Dis ; 812023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-37727973

RESUMO

Because the placenta is bathed in maternal blood, it is exposed to infectious agents and chemicals that may be present in the mother's circulation. Such exposures, which do not necessarily equate with transmission to the fetus, may primarily cause placental injury, thereby impairing placental function. Recent research has improved our understanding of the mechanisms by which some infectious agents are transmitted to the fetus, as well as the mechanisms underlying their impact on fetal outcomes. However, less is known about the impact of placental infection on placental structure and function, or the mechanisms underlying infection-driven placental pathogenesis. Moreover, recent studies indicate that noninfectious environmental agents accumulate in the placenta, but their impacts on placental function and fetal outcomes are unknown. Critically, diagnosing placental insults during pregnancy is very difficult and currently, this is possible only through postpartum placental examination. Here, with emphasis on humans, we discuss what is known about the impact of infectious and chemical agents on placental physiology and function, particularly in the absence of maternal-fetal transmission, and highlight knowledge gaps with potential implications for diagnosis and intervention against placental pathologies.


Assuntos
Feto , Placenta , Gravidez , Feminino , Humanos
20.
Drug Alcohol Depend ; 251: 110952, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37699287

RESUMO

BACKGROUND: Individuals who use cocaine have high rates of co-morbid alcohol use and when ethanol and cocaine are administered concurrently, the metabolite cocaethylene is formed. Cocaethylene is equipotent to cocaine in blocking dopamine reuptake and substitutes for cocaine in drug discrimination studies. However, no previous work has directly compared the reinforcing strength of cocaine to cocaethylene. METHODS: In Experiment 1, three individually-housed adult male rhesus macaques self-administer cocaine under a progressive-ratio (PR) schedule of reinforcement, during daily 4-hr sessions. Under this schedule, the primary dependent variable is the number of injections received, or the break point (BP). Saline, cocaine (0.001-0.3mg/kg/injection) and cocaethylene (0.0003-0.1mg/kg/injection) dose-response curves were determined. In Experiment 2, two female cynomolgus and one rhesus macaque responded under a concurrent schedule of drug (cocaine or cocaethylene) vs. 1.0-g banana-flavored food pellets, during daily 1-hr sessions. RESULTS: Both cocaine and cocaethylene functioned as reinforcers under the PR and concurrent choice schedules of reinforcement. Under the PR schedule, peak BPs were not significantly different, nor were ED50 values on the ascending limb, suggesting that cocaethylene has equal reinforcing strength and potency to cocaine. Under the concurrent drug-food choice procedure, cocaethylene was also equally potent to cocaine. CONCLUSIONS: Under two schedules of reinforcement designed to assess reinforcing strength, cocaethylene and cocaine were equipotent and of equal reinforcing strength. Because cocaethylene has a longer duration of action, it is important for studies designed to evaluate treatments for cocaine use to also consider the effects of these interventions on cocaethylene.


Assuntos
Cocaína , Animais , Masculino , Feminino , Macaca mulatta , Autoadministração , Relação Dose-Resposta a Droga , Cocaína/farmacologia , Esquema de Reforço
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