Journal of Tropical Medicine最新文献

Background: Surgical site infections resulting from trauma orthopedic surgery increase morbidity and mortality rates and generate additional costs for the healthcare system. Preoperative and postoperative blood parameters have been described as risk predictors for surgical site infection in other surgical areas. The purpose of this study was to assess the role of preoperative and postoperative hematological parameters in predicting the risk of surgical site infections in trauma orthopedic surgery. Methods: Data on patients' demographics were collected from their medical records and the operation reports. Preoperative and postoperative blood samples were collected for a complete blood count assay. The blood cell parameters as predictors of surgical site infection after trauma orthopedic surgery were determined by the Mann-Whitney U test to assess the differences in the median between the dependent and independent variables. p value < 0.05 was considered statistically significant. Results: Out of the 210 patients who were followed postsurgery, 14 (6.7%) developed surgical site infection following trauma orthopedic surgery. The mean age of the study participants was 33.08 ± 19.23 (Mean ± SD), with a range of 86 to 0.67 years old. Low preoperative hemoglobin level was identified as a predictor of surgical site infection following trauma orthopedic surgery (p=0.019). None of the postoperative blood parameters measured was significantly associated with surgical site infections after trauma orthopedic surgery in Northern Ghana. Conclusion: In conclusion, our study demonstrates that preoperative hemoglobin level is a useful hematological parameter for predicting surgical site infection following trauma orthopedic surgery. These inexpensive and common hematological parameters could assist in guiding preventive efforts to reduce surgical site infections and improve outcomes for vulnerable patients undergoing trauma orthopedic surgery. Assessing preoperative hemoglobin levels is crucial in identifying patients at increased risk of developing surgical site infections. Preoperative optimization, including incorporating hemoglobin levels into predictive risk models can help to assess these at-risk persons better. Educate patients on the need to optimize their hemoglobin levels before surgery and discuss potential interventions, including iron supplementation or transfusion.

This study aimed to evaluate the effectiveness of the algorithm used in HIV diagnosis and to propose an effective new algorithm for rapid diagnosis. In accordance with CDC algorithm, our laboratory uses Architect HIVAg/Ab for screening and Geenius HIV1/2 and Artus HIVirus-1 QS-RGQ for confirmation. The Geenius test was used as a reflex and the HIV-1-RNA required clinician order. The HIVAg/Ab test was performed in 82,882 sera and found to be reactive in 262 (0.3%). HIV-antibody confirmatory testing was performed on 79% of samples with a reactive screening test, and the presence of HIV-1 antibodies was confirmed in 51% (105/206). Half of the samples with positive-screening but negative-antibody confirmatory results were tested for HIV1-RNA, and viremia was detected in 5, confirming acute HIV1 infection. HIV1-RNA was not ordered for 49 samples with positive-screening and negative antibody-confirmation tests, and 16 of these were considered false-reactive by the clinician. The Geenius assay result was indeterminate in 1.45% (3/206) of the samples. In the algorithm, the number of Geenius tests would have been reduced by 25% if HIV-1-RNA had been applied as a reflex test to HIV-Ag/Ab positive samples and Geenius testing had been performed on RNA negative samples. A retrospective analysis showed that the HIV diagnostic algorithm was not fully implemented. An important factor was that clinicians did not order HIV-1-RNA-PCR from ELISA reactive and Geenius test negative patients. Requesting HIV-1 RNA PCR as a reflex test is thought to prevent patient losses and shorten the turnaround time of the HIV diagnosis.

Background: The development of insecticide resistance in malaria vectors has necessitated a need to evaluate new insecticide molecules with different modes of action. In the present study, Fludora Fusion 562.5 WP-SB (clothianidin 50% + deltamethrin 6.25% AI/kg) was evaluated for its efficacy and residual action for the control of pyrethroid-resistant malaria vector, Anopheles culicifacies (Diptera: Culicidae), during May 2017 to February 2018 in Gujarat state, India. Methods: Fludora Fusion at the dose of 225 mg AI/m² and bendiocarb at a dose of 400 mg AI/m² as a positive control were sprayed in 5 villages each in districts of Kheda, Vadodara, and Panchmahal. The persistence of their efficacy on different local surfaces was determined against An. culicifacies. Entomological indices such as indoor resting density, human landing collections, pyrethrum spray collections, and exit trap collections were monitored to assess the impact of spraying. Results: The observed residual action of Fludora Fusion on mud and cement surfaces was for 6 months and bendiocarb for 3-4 months on both surfaces. Indoor resting densities and parous rate of An. culicifacies were significantly lower in houses sprayed with Fludora Fusion compared to bendiocarb-sprayed houses. Daily entomological inoculation rate (EIR) declined from 1.275 during prespray period to 0.5225 in the Fludora Fusion arm and 0.3802 in the Ficam arm in postspray period, indicating a reduction in the malaria transmission potential of An. culicifacies in both arms. Conclusion: Based on the residual action of the Fludora Fusion on most common sprayed surfaces and its effects on the elements of vectorial capacity, Fludora Fusion at 225 mg/m² dose was found effective for more than 6 months and could be a potential option for the control of resistant mosquito vectors.

Silymarin is a polyphenolic flavonoid extracted from milk thistle. It has potent immunomodulatory effects and can inhibit the replication of influenza A virus (IAV). The present study aimed to determine the inflammatory and anti-inflammatory cytokine secretion patterns in mice before and after silibinin treatment. For this, bronchoalveolar lavage (BAL) fluids were collected from the thoracic cavity 5 days after the intervention, and viral quantification was performed using TaqMan Real-time PCR. Enzyme-linked immunosorbent assay (ELISA) was used to evaluate IFN-γ and IL-10 levels in serum and BAL samples. Finally, pathological damage to lung tissue was assessed by pathologists. The results reveal that silibinin pretreatment exhibits a dose-dependent immunomodulatory effect on IFN-γ and IL-10 levels. After the virus challenge, silibinin reduced immune cell infiltration in mouse BAL fluid. These data similarly suggest a remarkable immunomodulatory effect of silibinin. Silibinin also decreased lung damage following the virus challenge in the post-treatment group, but its lung protective properties seem to be due to a different mechanism than when it was administered before infection. Finally, high doses of silibinin (post-treatment) significantly reduced viral load in BAL fluid compared to the virus challenge group. These results support the idea that therapies aimed at moderating immune and inflammatory responses are essential to decrease the mortality rate caused by IAV infection. Silibinin has strong immunomodulatory properties, can inhibit IAV infection, and reduces lung tissue damage in a dose-dependent manner.

Glycosaminoglycan (GAG) molecules on the surface of red blood cells play an important regulatory role in the invasion of merozoites of apicomplexan protozoa. Heparan sulfate, a type of GAG molecule, has been identified as an important receptor facilitating the invasion of red blood cells by these parasites. Proteins in the parasite that exhibit strong affinity for heparin may play a pivotal role in this invasion process. This study aims to use proteomics to identify Babesia microti proteins with high binding affinity to heparin. Bioinformatics was utilized to analyze the subcellular localization and biological functions of these proteins. Candidate genes encoding proteins with strong heparin affinity will be expressed in a prokaryotic system to produce recombinant proteins. The interaction between these recombinant proteins and heparin will be characterized through heparin-binding experiments and other methods. Initially, a mouse model of B. microti was established and high-density B. microti were obtained. Heparin affinity chromatography was then used to purify natural B. microti proteins that can bind to heparin, identifying 186 B. microti proteins via ESI-MS that specifically interact with heparin. Further studies were carried out to analyze those specific proteins with unique peptide segments of two or more, yielding 15 B. microti proteins, most of which are cell surface proteins and secretory proteins. Based on mass spectrometry identification and subsequent analyses, BMSA5-1-1, B. microti peptidyl-prolyl cis-trans isomerase (BmPPIase), and chaperonin were selected for further study due to their potential impact on the invasion of red blood cells by B. microti. These candidate proteins were expressed as recombinant proteins using a prokaryotic expression system. In vitro heparin-binding assays demonstrated that these recombinant proteins specifically bind to heparin. Notably, BmPPIase and chaperonin recombinant proteins exhibited activity in specific heparin binding. Molecular interaction studies further confirmed the strong interaction between BmPPIase and heparin. In conclusion, this study used proteomic methods to identify 186 specific B. microti proteins with specific binding affinity to heparin, providing in-depth analysis of 15 key proteins. The findings confirmed that BmPPIase and chaperonin specifically bind to heparin, with molecular interaction experiments substantiating the strong interaction between BmPPIase and heparin.

The loa22 protein is highly conserved among pathogenic Leptospira serovars and it is expressed during both acute and chronic infections. The aim of this study was to clone and sequence of the loa22 protein-encoding gene of Leptospira serovars. In this study, 23 pathogenic Leptospira serovars and two nonpathogenic Leptospira serovars were used. These serovars were obtained from the microbial culture collection of Leptospira Reference Laboratory, Department of Microbiology, Razi Vaccine and Serum Research Institute, Karaj, Iran. Three serovars, including L. Sejroe Hardjo-bovis, L. Grippotyphosa, L. Canicola, are used in the preparation of the trivalent vaccine. The loa22 gene was amplified by specific primers and the PCR products were then purified using kit and were cloned into a pTZ57R/T vector and transformed in competent E. coli DH5α cells. The cells were then plated onto LB agar containing ampicillin and recombinant colonies subjected to colony PCR to confirm the presence of the Leptospiral gene. Positive colonies plasmid vector was isolated from cells by High Pure Plasmid Isolation Kit. The loa22 gene was detected in all 23 pathogenic serovars, while this gene was not observed in nonpathogenic L. biflexa. It was determined that the similarity percentage of the sequenced pathogenic serovars is between 95.5% and 100%. The results concluded that the loa22 gene was highly conserved among various pathogenic Leptospira serovars and can be used to develop an effective recombinant vaccine.

Background: Dengue virus infection is a major source of morbidity and mortality in the majority of tropical and subtropical nations. In Nepal, the first case of dengue was reported in 2004, followed by numerous outbreaks exerting a critical impact on public health. This study aims to describe the clinical and laboratory characteristics of dengue patients visiting a tertiary care hospital to see the trend of presentation. Method: Hospital based cross-sectional study was conducted among diagnosed cases of dengue from April 2023 to September 2023. A total of 692 patients undergoing testing by commercially available dengue rapid diagnostic tests were recruited and categorized dengue positive (if NS1 and/or IgM positive) and dengue negative (NS1, IgM, and IgG all negative or only IgG positive). The dengue-positive cases were further subdivided into three groups (only NS1 positive, only IgM positive, both NS1 and IgM positive). Additionally, biochemical and hematological analyses were performed, and results were compared between positive and negative cases by using Mann-Whitney U test while subgroups of dengue-positive cases were compared using Kruskal-Wallis H test. Results: Most common symptoms were fever (94.5%) followed by headache (79.8%) and myalgia (74.7%). Among 346 dengue-positive subjects, 53.2% (n = 184) were NS1-only positive, 21.7% (n = 75) were IgM-only positive, and 25.1% (n = 87) were both NS1+IgM positive. Thrombocytopenia (n = 179, 51.7%), leucopenia (n = 99, 28.6%), increased SGPT (n = 182, 52.6%), increased SGOT (n = 188, 54.3%) were seen among dengue positive patients. Leukopenia was more severe in patients with only NS1 positive cases (p = 0.008) whereas thrombocytopenia (p ≤ 0.001) was more severe in patients with both IgM and NS1 positive cases. Conclusion: Our study depicted there is a marked alteration in biochemical and hematological parameters specifically thrombocytopenia, leukopenia, increased transaminase levels, and high prothrombin time seen in dengue positive cases.

Background: A diverse range of pollutants, including heavy metals, agrochemicals, pharmaceutical residues, illicit drugs, personal care products, and other anthropogenic contaminants, pose a significant threat to aquatic ecosystems. The Winam Gulf of Lake Victoria, heavily impacted by surrounding human activities, faces potential contamination from these pollutants. However, studies exploring the presence of antibiotic resistance genes (ARGs) in the lake remain limited. In the current study, a shotgun metagenomics approach was employed to identify ARGs and related pathways. Genomic DNA was extracted from water and sediment samples and sequenced using the high-throughput Illumina NovaSeq platform. Additionally, phenotypic antibiotic resistance was assessed using the disk diffusion method with commonly used antibiotics. Results: The analysis of metagenomes sequences from the Gulf ecosystem and Comprehensive Antibiotic Resistance Database (CARD) revealed worrying levels of ARGs in the lake. The study reported nine ARGs from the 37 high-risk resistant gene families previously documented by the World Health Organization (WHO). Proteobacteria had the highest relative abundance of antibiotic resistance (53%), Bacteriodes (4%), Verrucomicrobia (2%), Planctomycetes Chloroflexi, Firmicutes (2%), and other unclassified bacteria (39%). Genes that target protection, replacement, change, and antibiotic-resistant efflux were listed in order of dominance. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed antibiotic resistance to beta-lactamase and vancomycin. Phenotypic resistance to vancomycin, tetracycline, sulfamethoxazole, erythromycin, trimethoprim, tetracycline, and penicillin was reported through the zone of inhibition. Conclusions: This study highlights that the Winam Gulf of Lake Victoria in Kenya harbors a diverse array of antibiotic-resistant genes, including those conferring multidrug resistance. These findings suggest that the Gulf could be serving as a reservoir for more antibiotic-resistant genes, posing potential risks to both human health and aquatic biodiversity. The insights gained from this research can guide policy development for managing antibiotic resistance in Kenya.

Malaria remains a significant global health challenge, with the deadliest infections caused by Plasmodium falciparum. In light of the escalating drug resistance and the limited effectiveness of available vaccines, innovative treatment approaches are urgently needed. This study explores the potential of the probiotic Limosilactobacillus fermentum YZ01, isolated from traditionally fermented kindirmo milk, to modify host responses to Plasmodium berghei ANKA infection. Twenty-five male BALB/c mice were grouped and administered various treatments, including probiotic-enriched yogurt alone or in combination with antibiotics. Parameters assessed included gut lactic acid bacteria (LAB) composition, parasitaemia progression, survival rates, and immune response dynamics over a 21-day postinfection period. The probiotic treatment significantly altered gut microbiota, evidenced by increased LAB counts and modulated immune responses, notably enhancing IgM and IL-4 production while reducing IFN-γ levels. Mice receiving prolonged probiotic treatment exhibited delayed parasitaemia onset, reduced mortality rates, and a more robust immune response compared to control groups. These outcomes suggest that probiotic intervention not only tempers the pathological effects of malaria but also enhances host resilience against infection. This study underscores the role of gut microbiota in infectious disease pathogenesis and supports probiotics as a promising adjunct therapy for malaria management.

Enteric fever is a significant health problem in developing countries caused by Salmonella enterica serovars Typhi and Paratyphi. Unfortunately, the burden of the disease remains high not only because of the complications related to the disease but also, especially, because of the spread of the strains of Salmonella resistant to antibiotics. The aim of the present study was to evaluate the antibiotic resistance patterns of Salmonella Typhi and Paratyphi clinical isolates as well as the risk factors associated with infection. This cross-sectional study was conducted from June 2020 to September 2021. One thousand and seventy-six patients in the age range (1- ≥ 50 years) were recruited including 423 (39.31%) infected with S. Typhi, 115 (10.68%) infected with S. Paratyphi, and 538 (50%) noninfected after obtaining their informed consent using a face-to-face interview and questionnaire. The stool samples were collected in clean and sterile boxes reserved for this purpose and were cultured. Demographic parameters such as sex, age, occupation, water source, level of education, as well as clinical signs and symptoms were obtained. The resistance profile determination was carried out by the disk diffusion method. A multivariate logistic regression analysis was performed to identify factors associated with infection. Results of multivariate logistic regression analysis showed positive and significant associations (OR > 1; p < 0.05) between enteric fever and women among the age groups: 1-10 years, 11-20 years, and 21-30 years. These positive associations were also noted in patients who ate shellfish, salads, fruits, and vegetables; in patients who consumed ice cubes; as well as those who consumed food and drinks offered by ambulant merchants. This indicated that they are more likely to be infected by S. enterica than others. The level of multidrug-resistant (MDR) S. enterica to first-line antimicrobial agents ampicillin, chloramphenicol, and co-trimoxazole was high and selectively distributed according to age groups, marital status, profession, level of education, source of water, and lifestyle. The results highlighted the emergence of MDR S. enterica isolated in the study population, demonstrating resistance to first-line drugs, fluoroquinolones, and third-generation cephalosporins. Further studies with large-scale samples are needed to validate the present results and to monitor MDR S. Typhi and S. Paratyphi serovars in other parts of Cameroon.