Journal of Tropical Medicine最新文献

Diverse virulence genes encode for the Type III secretion system (T3SS) in bacteria. In Salmonella, these genes are located in the Salmonella pathogenicity Islands 1 and 2 (SPI-1 and SPI-2), and they facilitate bacterial invasion and replication within macrophages, contributing to the burden of nontyphoidal Salmonella infections. In this study, we investigated the prevalence of selected virulence-encoding genes in 30 laboratory stocks of Salmonella enterica serovar Enteritidis from Nigeria (16 isolates) and nonclinical sources comprising poultry and seafood from India (14 isolates). Analysis of PCR amplicons revealed that the genes sseB, sseD, sseF, sseT, and invH were conserved in all the isolates except for two isolates obtained from clams, which did not have the sseD and sseF genes. In addition, the sseC and sseG genes were absent from all the tested isolates. This study provides insights into the distribution of selected T3SS genes among Salmonella spp. isolated from clinical and raw animal food sources in Nigeria and India, respectively.

Epstein-Barr nuclear antigen 1 (EBNA1) is an attractive therapeutic target for identifying pharmaceutical drug molecules to fight Epstein-Barr virus (EBV) contagion because of its key function in viral reproduction. To find potent EBNA1 inhibitors, the Naturally Occurring Plant-based Anticancer Compound-Activity-Target (NPACT) database, including > 1500 compounds, was filtered utilizing computational approaches. The efficiency of the docking technique used to anticipate the inhibitor-EBNA1 binding pose was initially evaluated based on obtainable experimental data. Upon the computed docking scores, molecular dynamics simulations (MDSs) were executed for the most superior NPACT compounds bound to EBNA1, accompanied by binding affinity estimations utilizing the MM/GBSA approach. According to binding affinity computations over 200 ns MDS, bitucarpin A demonstrated stronger ΔG _binding than KWG, an EBNA1 reference inhibitor, with values of -39.1 and -32.4 kcal/mol, respectively. Post-MD analyses assured the steadiness of bitucarpin A inside the EBNA1 binding pocket over 200 ns MDS. Besides, pharmacokinetics, physicochemical, and toxicity features were predicted for bitucarpin A and demonstrated its promising oral bioavailability. Density functional theory calculations were executed, and their outcomes substantiated the results given by docking and MDS computations. According to these findings, bitucarpin A showed promising inhibitory activity as a potent EBNA1 inhibitor that may be a prospective anti-EBV drug candidate.

Background: Medicinal plants are used in Namibia for oral hygiene and to treat oral diseases. Validating the content and efficacy of medicinal chewsticks used in communities helps to provide proof of concept of medicinal plants used as a complementary/alternative medicine for oral diseases. Aim: This study presents the first report on quantified phytoconstituents, antimicrobial, time-kill kinetics, and biofilm inhibition properties of Diospyros lycioides organic and aqueous extracts against Enterococcus faecalis. Methodology: Dry plant materials were ground into powder and macerated in methanol and distilled water. Different phytoconstituents were quantified by Folin-Ciocalteu colorimetric method, ferric reducing antioxidant power assay, and DPPH free radical scavenging. An antibacterial assay was performed using the agar well diffusion method and a resazurin 96-well-based assay. Kill-time assay was done at various concentrations over 4 h. Biofilm inhibition was done using the crystal violet method. Results: Higher total flavonoid, total phenol contents, and free radical scavenging abilities were reported in methanol twig extracts. Inhibition zones of 28 ± 0.82 mm, with MICs of 15.6 ± 0.00 μg/mL, are reported against E. faecalis. The bactericidal endpoint of D. lycioides organic extracts for E. faecalis was reached after 4 h of incubation at 8 × MIC (124.8 μg/mL). These were comparable to the positive control, gentamicin. The organic extracts showed ≥ 50% biofilm inhibition against root canal-infecting E. faecalis at concentrations between 7.8 and 500 μg/mL, indicating strong biofilm inhibition. Conclusion: The study demonstrated that D. lycioides crude extracts have promising antibacterial properties and can eradicate E. faecalis biofilms in root canal treatments.

Background: Several studies have focused on the town of Kamituga, the epicentre of the current MPOX Clade Ib epidemic, in South Kivu Province, in the east of the Democratic Republic of Congo. However, the disease is widespread in several health zones in this province. Objectives: The aim of this study was to describe the clinical characteristics and vital prognosis of admissions for MPOX in the city of Bukavu (21,808 inhabitants/km²), in the province of South Kivu. Methodology: Between 1 July and 31 December 2024, MPOX patients were recruited as and when they were admitted to the treatment centre at the Bukavu university clinics. For each patient, clinical characteristics and outcome were sought. Results: Of the 343 patients hospitalized during this study period, 201 (58.6%) were men and 142 (41.4%) were women (p=0.001). The median age was 21.0 (11.0-27.7) years. Traders (42.3%) and field workers (24.7%) were more numerous. Contact with an MPOX case (61.2%) was the most frequent mode of contamination. The frequency was 70.2% for elevated white blood cells, 73.0% for elevated c-reactive protein, 37.9% for anemia, 43.1% for genital lesions, 7.0% for pregnancy and 2.6% for HIV. Finally, during the 2400 patient-day observation period, 3 patients subsequently died (0.8%). The incidence of death was 1.25/1000 patient days. Conclusion: The results of this study show that, in the city of Bukavu, MPOX is a disease of young people. Contact with a case of MPOX was the most important mode of contamination, and the professions at risk were trade and field work. Thus, the list of professions at risk of MPOX to be vaccinated must be established according to each region.

Cancer patients are at a high risk of Candida infections, and candidemia may aggravate the prognosis among patients with cancers. To investigate the incidence, mortality, risk factors, and antifungal resistance of candidemia among cancer patients, 100 inpatients with malignant solid tumors and candidemia in Fujian Province, southern China, during the period from January 2014 through December 2023 were recruited. Among the study subjects, Candida albicans was the predominant Candida species (50%), and the prevalence of candidemia showed an overall tendency towards a slight decline during the study period. Candida tropicalis showed 10.53% prevalence of resistance to fluconazole, voriconazole and itraconazole, while C. albicans, Candida glabrata and Candida parapsilosis were all totally susceptible to fluconazole, voriconazole, itraconazole and amphotericin B. The overall 30-day crude mortality of candidemia was 67% among cancer patients, and there was no significant difference between the mortality due to Candida catheter-related bloodstream infection (CRBSI) and bloodstream infection (BSI) (p = 0.59). Multivariate Cox regression analysis identified that the presence of cardiovascular diseases and use of two to three catheters (OR = 385.064, p = 0.005) increased the risk of candidemia among cancer patients. Our data demonstrate an overall tendency towards a slight decline in the prevalence of candidemia and a high mortality rate of candidemia among cancer patients in southeastern China from 2014 to 2023, and development of cardiovascular diseases and use of two to three catheters may increase the risk of candidemia among cancer patients.

Background: Mycetoma is a public health problem with a high prevalence in Africa. Materials and Methods: The study included 50 cases presenting at a tertiary care research hospital, retrospectively (cases we visited and followed up between November 2022 and March 2023) and prospectively between 1 August and 30 September 2024. Demographic characteristics, clinical features, physical examination findings, and diagnostic methods were reported. Results: Out of 50 patients, 76% were male and 24% were female. The mean age (mean ± SD) of all cases was 35.50 ± 15.14. The most affected occupational group was farmers (44%). All patients presented with complaints of swelling. Symptoms continued for > 1-5 years in about 30 percent of cases. The diagnosis was made by pathological biopsy in 62% of the cases. The lower extremities were most commonly affected (80%), and subcutaneous soft tissue and muscle involvement was also commonly encountered. Bone involvement was higher in eumycetoma cases as compared to actinomycetoma. Conclusion: The frequency of myçetoma cases, which can involve all parts of the lower extremities, was determined, especially in Somali farmers. Difficulties in diagnosis and follow-up were analyzed.

Background: Even in well-resourced settings, the case-fatality rate of melioidosis approaches 10%. This has prompted an interest in identifying adjunctive therapies that might improve survival. A prospective, multicentre study in Thailand suggested that statin therapy may reduce the incidence of pneumonia in patients with melioidosis; however, the impact of statins on the clinical course of patients with the infection is incompletely defined. Materials and Methods: We examined all cases of culture-confirmed melioidosis in Far North Queensland, tropical Australia, since October 2016 to determine if statin therapy influenced the clinical phenotype of melioidosis and the patients' clinical course. Results: Of 321 individuals with culture-confirmed melioidosis, 100 (31%) were prescribed a statin at the time of their diagnosis. There was no difference in the clinical phenotype of patients who were- and were not-taking statin therapy. Pulmonary involvement, specifically, was no less common in patients taking a statin (79/100 [79%] versus 175/221 [79%], p = 0.97). A smaller proportion of patients taking statin therapy died before hospital discharge, but this difference did not reach statistical significance (5/100 [5%] versus 26/221 [12%], p = 0.07). This finding was at least partially explained by the fact that fewer patients with an active malignancy were taking a statin (7/37 [19%] versus 93/284 [33%] patients without a malignancy, p = 0.09) and that, in multivariable analysis, patients with malignancy were more likely to die before hospital discharge (odds ratio [95% confidence interval]: 4.73 [1.62-13.87], p = 0.005). Among 290 individuals surviving to hospital discharge, there was no difference in 12-month mortality between those that were-and were not-prescribed a statin at presentation (11/95 [12%] versus 23/195 [12%], p = 0.96). Conclusion: Statin therapy does not appear to have any significant influence on the clinical phenotype of patients with melioidosis. There is also no appreciable impact of statin therapy on patients with melioidosis' short-term or 12-month survival.

Dengue is one of the major public health concerns in tropical and subtropical countries. In addition to neurological sequelae which are well documented, emerging evidence suggests that dengue may also lead to psychiatric sequelae including mood disorders, psychosis, anxiety, and body dysmorphic disorder. This narrative review aims to synthesize the existing literature to explore the psychiatric manifestations and postulated pathophysiological mechanisms and identify predictors and treatment of psychiatric sequelae in dengue. This review identified 30 studies including observational studies, case reports, and case series. The immune-inflammatory responses due to cytokine dysregulation, blood-brain barrier disruption, direct viral effects, and epigenetic mechanisms with histone deacetylase activation are possible contributors to psychiatric sequelae in dengue. The main predictors include severity of dengue, thrombocytopenia, central nervous system involvement, febrile and critical phase of illness, specific dengue virus serotypes (DENV-2 and DENV-3), and stress due to hospitalization. Psychiatric symptoms often persist beyond the acute phase, highlighting the importance of long-term follow-up to evaluate the impact of dengue on mental health. Additionally, comparisons with other Flaviviridae viruses, such as Zika, West Nile, and Japanese encephalitis viruses, reveal both shared and distinct psychiatric implications, suggesting potential virus-specific mechanisms. The current treatment approaches are largely extrapolated from general psychiatric practice, with limited research on targeted interventions. Future research should focus on standardized diagnostic assessment, longitudinal follow-up, diagnostic biomarkers, and developing targeted treatment strategies to improve clinical outcomes. With rising cases of dengue, integrating psychiatric screening into routine dengue management may enhance early recognition and intervention. Hence, a multidisciplinary research approach involving psychiatrists, neurologists, infectious disease specialists, immunologists, and policymakers is crucial for addressing psychiatric sequelae in dengue fever and mitigating the detrimental implications on public health.

The increase in antibiotic resistance has increased the demand for new and safe therapeutic options. Herbal beverages, whether used alone or combined with standard antibiotics, have shown promise in combating drug-resistant bacteria. This study investigated the antibacterial activity and combinatorial efficacy of common herbal beverages prepared from clove, cinnamon, and thyme. The inhibitory and cidal effects were examined using MIC and MBC on a panel of 14 multidrug-resistant strains and clinical isolates (resistant to ciprofloxacin (CIP), tetracycline (TET), and erythromycin (ERY)), including Staphylococcus aureus, Salmonella and Shigella species, Escherichia coli, and Pseudomonas aeruginosa. The combinatorial efficacy was further evaluated using a fractional inhibitory concentration index (FICi). Qualitative phytochemical screening of the plant extracts followed established protocols. The tested botanicals showed inhibitory effects against all 14 tested bacteria, with varying degrees of potency (MICs ranged from 13.33 ± 2.67 to 1024 ± 0.00 μg/mL). The aqueous and hydroethanolic extracts of clove demonstrated the highest activity, with most MIC values ranging from 13.33 ± 2.67 to 256 ± 0.00 μg/mL, indicating excellent to good efficacy. When combined with TET, CIP, and ERY, clove extracts exhibited significant synergistic and additive interactions, leading to more than a 100-fold reduction in the MICs of the antibiotics in some cases. The most notable synergistic interactions were observed with the combination of clove hydroethanol extract with TET (FICi = 0.078 ± 0.016) against P. aeruginosa. The findings indicate possible optimization of antibiotic treatment strategies using these combinations, which may help mitigate antibiotic resistance and improve patient outcomes. However, an antagonistic effect was observed with the clove aqueous extract and CIP on S. aureus, which may require further evaluation. Phytochemical analysis revealed the presence of several major bioactive secondary metabolites, including phenols, flavonoids, tannins, anthocyanins, saponins, and alkaloids. Overall, the tested botanicals, particularly clove, demonstrate considerable potential in fighting drug-resistant bacteria, either through direct action or by enhancing the effectiveness of existing antibiotics. Further, in vivo testing and investigation of the mechanisms behind the active combinations are recommended to assess their overall efficacy.