Background On the Indian subcontinent, visceral leishmaniasis (VL) incidence is on track to reach elimination goals by 2020 in nearly all endemic districts. Although not included in official targets, previous data suggest post-kala-azar dermal leishmaniasis (PKDL) patients can act as an infection reservoir. Methods We conducted xenodiagnosis on 47 PKDL patients and 15 VL patients using laboratory-reared Phlebotomus argentipes. In direct xenodiagnosis, flies were allowed to feed on the patient’s skin for 15 minutes. For indirect xenodiagnosis, flies were fed through a membrane on the patient’s blood. Five days later, blood-fed flies were dissected and examined by microscopy and/or polymerase chain reaction (PCR). A 3-mm skin snip biopsy (PKDL) or venous blood (VL) was processed by quantitative PCR. Results Twenty-seven PKDL patients (57.4%) had positive results by direct and/or indirect xenodiagnosis. Direct was significantly more sensitive than indirect xenodiagnosis (55.3% vs 6.4%, P < .0001). Those with positive xenodiagnosis had median skin parasite loads >1 log10 unit higher than those with negative results (2.88 vs 1.66, P < .0001). In a multivariable model, parasite load, nodular lesions, and positive skin microscopy were significantly associated with positive xenodiagnosis. Blood parasite load was the strongest predictor for VL. Compared to VL, nodular PKDL was more likely and macular PKDL less likely to result in positive xenodiagnosis, but neither difference reached statistical significance. Conclusions Nodular and macular PKDL, and VL, can be infectious to sand flies. Active PKDL case detection and prompt treatment should be instituted and maintained as an integral part of VL control and elimination programs.
Quercetin, a bioactive flavonoid with anti-inflammatory, immunosuppressive, and protective properties, is a potential agent for the treatment of rheumatoid arthritis (RA). Collagen-induced arthritis (CIA) is the most commonly used animal model for studying the pathogenesis of RA. This study analysed the therapeutic role of quercetin in collagen-induced arthritis in C57BL/6 mice. The animals were allocated into five groups that were subjected to the following treatments: negative (untreated) control, positive control (arthritis-induced), arthritis+methotrexate, arthritis+quercetin, and arthritis+methotrexate+quercetin. Assessments of weight, oedema, joint damage, and cytokine production were used to determine the therapeutic effect of quercetin. This study demonstrated for the first time the anti-inflammatory and protective effects of quercetin in vivo in CIA. The results also showed that the concurrent administration of quercetin and methotrexate did not offer greater protection than the administration of a single agent. The use of quercetin as a monotherapeutic agent resulted in the lowest degree of joint inflammation and the highest protection. The reduced severity of the disease in animals treated with quercetin was associated with decreased levels of TNF-α, IL-1β, IL-17, and MCP-1. In conclusion, this study determined that quercetin, which was non-toxic, produced better results than methotrexate for the protection of joints from arthritic inflammation in mice. Quercetin may be an alternative treatment for RA because it modulates the main pathogenic pathways of RA.
Acute rheumatic fever and rheumatic heart disease (ARF/RHD) have long been described as autoimmune sequelae of Streptococcus pyogenes or group A streptococcal (GAS) infection. Both antibody and T-cell responses against immunodominant GAS virulence factors, including M protein, cross-react with host tissue proteins, triggering an inflammatory response leading to permanent heart damage. However, in some ARF/RHD-endemic regions, throat carriage of GAS is low. Because Streptococcus dysgalactiae subspecies equisimilis organisms, also known as β-hemolytic group C streptococci and group G streptococci (GGS), also express M protein, we postulated that streptococci other than GAS may have the potential to initiate or exacerbate ARF/RHD. Using a model initially developed to investigate the uniquely human disease of ARF/RHD, we have discovered that GGS causes interleukin 17A/interferon γ-induced myocarditis and valvulitis, hallmarks of ARF/RHD. Remarkably the histological, immunological, and functional changes in the hearts of rats exposed to GGS are identical to those exposed to GAS. Furthermore, antibody cross-reactivity to cardiac myosin was comparable in both GGS- and GAS-exposed animals, providing additional evidence that GGS can induce and/or exacerbate ARF/RHD.
Biomonitoring studies can provide valuable insights into human mycotoxin exposure, especially when food contaminant data are scarce or unavailable as in Bangladesh. First biomonitoring data in Bangladeshi adults indicated exposure to the nephrotoxic mycotoxins ochratoxin A (OTA) and citrinin (CIT). This led us to conduct a follow-up study with analysis of urinary biomarkers for both CIT and OTA to investigate regional and seasonal influences on mycotoxin exposure in two Bangladeshi cohorts. In total, 164 urines were collected (n = 69 in summer, n = 95 in winter) from residents of a rural and an urban area, among which there were 62 participants enrolled in both sampling periods. Most urines had detectable biomarker levels (OTA, CIT and its metabolite dihydrocitrinone, HO-CIT), with more or less pronounced differences with regard to season and region. In both cohorts, OTA was found at a mean level of 0.06 ± 0.10 ng/mL urine (range 0.01-0.55 ng/mL) in summer and a mean of 0.19 ± 0.38 ng/mL (range 0.01-1.75 ng/mL) in winter season. A season difference was significant in the rural cohort, but not in the urban cohort, and slightly higher mean OTA levels in the rural compared to the urban cohort were only observed in winter urines. CIT biomarkers showed more pronounced variations, with a CIT mean of 0.10 ± 0.17 ng/mL (range 0.02-1.22 ng/mL) and HO-CIT mean of 0.42 ± 0.98 ng/mL (range 0.02-5.39 ng/mL) in summer, and CIT mean of 0.59 ± 0.98 ng/mL (range 0.05-5.03 ng/mL) and HO-CIT mean of 3.18 ± 8.49 ng/mL (range 0.02-46.44 ng/mL) in winter urines of both cohorts. In both seasons, total CIT biomarker concentrations were significantly higher in the rural cohort than in the urban cohort. A provisional daily intake for CIT was calculated and exceeded a preliminary value set by EFSA (0.2 µg/kg/d) in 10 and 24 % of participants in summer and winter, respectively. No significant correlations were found between urinary biomarker levels and intake of certain types of food, except for a positive trend for higher rice consumption. Our results in the Bangladeshi population indicate frequent co-exposure to nephrotoxic mycotoxin food contaminants that vary by season and region.
Antimicrobial resistance (AMR) has become an emerging health issue globally, posing a threat to zoonotic pathogens and foodborne diseases. In Bangladesh, the poultry sector supplies the majority of the demand for animal-source protein. The irrational and excessive use of antimicrobials (AMU) has been observed in the poultry sector. The development of AMR is associated with many factors, including the knowledge and attitudes of poultry farmers. Therefore, AMR reduction requires intervention from all the stockholders, including the farmers who are considered as end users of antimicrobials. This current research conducted a cross-sectional study to assess the knowledge, attitudes, and practices (KAP) of poultry farmers on AMU and AMR in Bangladesh. We determined the KAP of poultry farmers (broiler and layer farmers) of some selected districts of the country using a tested and paper-based questionnaire. The results demonstrated that most of the respondents have insufficient KAP regarding AMU and AMR. The respondents used a variety of antimicrobials primarily in the treatment of various diseases in poultry. One-third of the farmers did not seek antimicrobials from registered vets. Instead, they depended on others or themselves. The factor score analysis further revealed that the farmers’ demographic and socioeconomic variables were significant factors influencing the KAP. An adjusted logistic regression analysis showed that older farmers with 9–12 years of farming experience and graduate-level education, engaging in medium-sized layer farming, were more likely to have correct KAP on AMU and AMR. Further, farmers from the Cox’s Bazar region showed correct knowledge, whereas farmers of the Chattogram region showed a correct attitude towards AMU and AMR. A Spearman’s rank-order correlation revealed a positive association between knowledge–attitudes and knowledge–practices. The findings of the current investigation provide baseline evidence about the KAP of poultry farmers from low-income resources and offer insights into designing interventions and policies for the use of AMU and AMR in Bangladesh.
Citrinin (CIT) is a mycotoxin contaminant in food commodities and can co-occur with ochratoxin A (OTA), another nephrotoxic contaminant in food and feed. Presence of OTA in maize from Bangladesh has been reported, but no data exist on CIT occurrence in food or feed in Bangladesh. Since biomonitoring provides the best approach to assess human exposure to contaminants from various sources and by all routes, a validated method for biomarker analysis has been used to investigate the presence of CIT and its metabolite dihydrocitrinone (HO-CIT) in urines from two Bangladeshi cohorts: Both analytes were determined in urine samples collected from inhabitants of a rural (n=32) and an urban (n=37) area in the Rajshahi district of Bangladesh. After cleanup by immunoaffinity columns, extracts were analyzed by LC-MS/MS; the limits of detection for CIT and HO-CIT in urine were 0.02 and 0.05 ng/mL, respectively. CIT and HO-CIT were detectable in 94 and 71% of all urine samples. Urinary biomarker levels did not show significant correlations with age, gender, and body mass index of the donors. However, excretion of CIT together with its metabolite HO-CIT was significantly higher (p<0.01) in the rural cohort (mean 1.1±1.9 ng/mL) than in the urban cohort (mean 0.14±0.14 ng/mL). This clearly indicates differences in mycotoxin exposure. As food habits differ between rural and urban people and also their main areas of occupation, further research is needed with regard to the major contributors of CIT exposure in the two cohorts. In conclusion, this first biomarker analysis indicates widespread and variable exposure to CIT in Bangladeshi adults.
Abstract.We compared the efficacy of three intervention packages for active case detection (ACD) of visceral leishmaniasis (VL)/post–kala-azar dermal leishmaniasis (PKDL) combined with sandfly control around an index case. The packages were 1) no kala-azar transmission activity involving indoor residual spraying (IRS) with deltamethrin, peri-domestic deployment of larvicide with temephos, and house-to-house search for cases; 2) fever camp (FC) plus durable wall lining (DWL) with deltamethrin; and 3) FC plus insecticide (deltamethrin) impregnated bed-nets (ITN) around an index case. Fever camp includes 1-day campaign at the village level to screen and diagnose VL, PKDL, leprosy, malaria, and tuberculosis among residents with chronic fever or skin disease. Efficacy was measured through yield of new cases, vector density reduction, and mortality at 1, 3, 6, 9, and 12 months following intervention. Fever camp + DWL was the most efficacious intervention package with 0.5 case detected per intervention, 79% reduction in vector density (incidence rate ratio [IRR] = 0.21, P = 0.010), and 95.1% (95% confidence interval: 93.4%, 96.8%) sandfly mortality at 12 months. No kala-azar transmission activity was efficacious for vector control (74% vector reduction, IRR = 0.26, P < 0.0001 at 9 months; and 84% sandfly mortality at 3 months), but not for case detection (0 case per intervention). Fever camp + ITN was efficacious in detection of VL/PKDL cases (0.43 case per intervention), but its efficacy for vector control was inconsistent. We recommend index case–based FC for ACD combined with DWL or IRS plus larvicide for sandfly control during the consolidation and maintenance phases of the VL elimination program of the Indian subcontinent.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
334 Leonard St
Brooklyn, NY 11211
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.