Py-CoMFA, docking, and molecular dynamics simulations of Leishmania (L.) amazonensis arginase inhibitors.

Leishmaniasis is a disease caused by a protozoan of the genus Leishmania, affecting millions of people, mainly in tropical countries, due to poor social conditions and low economic development. First-line chemotherapeutic agents involve highly toxic pentavalent antimonials, while treatment failure is mainly due to the emergence of drug-resistant strains. Leishmania arginase (ARG) enzyme is vital in pathogenicity and contributes to a higher infection rate, thus representing a potential drug target. This study helps in designing ARG inhibitors for the treatment of leishmaniasis. Py-CoMFA (3D-QSAR) models were constructed using 34 inhibitors from different chemical classes against ARG from L. (L.) amazonensis (LaARG). The 3D-QSAR predictions showed an excellent correlation between experimental and calculated pIC50 values. The molecular docking study identified the favorable hydrophobicity contribution of phenyl and cyclohexyl groups as substituents in the enzyme allosteric site. Molecular dynamics simulations of selected protein-ligand complexes were conducted to understand derivatives' interaction modes and affinity in both active and allosteric sites. Two cinnamide compounds, 7g and 7k, were identified, with similar structures to the reference 4h allosteric site inhibitor. These compounds can guide the development of more effective arginase inhibitors as potential antileishmanial drugs.

Enabling product development partnerships to bring forward the next generation of health technologies.

Over the past quarter century, product development partnerships (PDPs) have importantly brought health technologies, particularly for neglected diseases, to market for low- and middle-income countries (LMICs). With public sector financing, PDPs de-risk the gulf between where the global burden of disease falls and where paying markets exist. From fighting COVID-19 to developing novel antibiotics, the work of PDPs now extends beyond these traditional bounds. As PDPs have shepherded more health technologies to market, they are also confronting new access challenges. This article lays out 5 areas to strategically leverage the PDP model for better access to new health technologies. Making the case for enhanced support of the PDP approach will require greater transparency, as well as recognition of the contributions made by both public and private sector partners. The governance and funding of PDPs must be accountable to meeting the needs and building capacity of target beneficiaries in LMICs. To take an end-to-end approach, PDPs must work in tandem with other public sector institutions as well as local manufacturers as part of a larger innovation ecosystem. PDPs will need to keep pace with both the dynamics of diseases and markets in delivering the next generation of much needed health technologies.

Product development partnerships (PDPs) play an important role in bringing new and needed health technologies to market, particularly in low- and middle-income countries. As these products emerge from the R&D pipeline, new access challenges in paying for and delivering them in the health care system have emerged. The COVID-19 pandemic has also both stretched and tapped into this work. These developments provide a window of opportunity, both to take stock of lessons learned and of strategic opportunities to leverage the PDP model beyond its traditional bounds of neglected diseases. Greater transparency and recognition of the contributions of PDPs, accountability of governance and surety of financing, and coordination with pooled procurement and local manufacturing initiatives can build a foundation for even more impactful contributions in the future.

N-Pyrazolyl- and N-Triazolylamines and -ureas as Antileishmanial and Antitrypanosomal Drugs.

Three types of modifications of antileishmanial pyrazole lead compounds 7 and 8 were conducted to expand the relationships between structural features and antileishmanial/antitrypanosomal activity: (1) the pyrazole core was retained or replaced by a 1,2,4-triazole ring; (2) various aryl moieties including 2-fluorophenyl, pyridin-3-yl and pyrazin-2-yl rings were attached at 3-position of the core azole; (3) either arylmethylamino or ureido substituents were introduced at 5-position of the azole core. The synthesis followed established routes starting with esters 9 or 15 and anhydride 21. The synthesized 3-arylpyrazoles and 3-aryl-1,2,4-triazoles showed only very low antileishmanial activity. The 2-fluorophenyl-substituted pyrazole 18c revealed the highest antileishmanial activity of this series of compounds, but its IC50 value (20 µM) still indicates low activity. However, low micromolar antitrypanosomal activity was detected for the pyridin-3-yl-substituted pyrazoles 12b (IC50 = 4.7 µM) and 14a (IC50 = 2.1 µM). Their IC50 values are comparable with the IC50 values of the reference compounds benznidazole and nifurtimox. Whereas only low unspecific cytotoxicity at the primary peritoneal mouse macrophages (PMM) was detected, considerable cytotoxicity at MRC-5 human fibroblast cells was found for both pyrazoles 12b an 14a. The activity of pyrazole 12b against T. cruzi is 4-fold higher than its unspecific MRC-5 cytotoxicity.

Effect of an exercise-based cardiac rehabilitation program on quality of life of patients with chronic Chagas cardiomyopathy: results from the PEACH randomized clinical trial.

To investigate the effect of an exercise-based cardiac rehabilitation program on the quality of life (QoL) of patients with chronic Chagas cardiomyopathy (CCC). PEACH study was a single-center, superiority randomized clinical trial of exercise training versus no exercise (control). The sample comprised Chagas disease patients with CCC, left ventricular ejection fraction < 45%, without or with HF symptoms (CCC stages B2 or C, respectively). QoL was assessed at baseline, after three months, and at the end of six months of follow-up using the SF-36 questionnaire. Patients randomized for the exercise group (n = 15) performed exercise training (aerobic, strength and stretching exercises) for 60 min, three times a week, during six months. Patients in the control group (n = 15) were not provided with a formal exercise prescription. Both groups received identical nutritional and pharmaceutical counseling during the study. Longitudinal analysis of the effects of exercise training on QoL, considering the interaction term (group × time) to estimate the rate of changes between groups in the outcomes (represented as beta coefficient), was performed using linear mixed models. Models were fitted adjusting for each respective baseline QoL value. There were significant improvements in physical functioning (ß = + 10.7; p = 0.02), role limitations due to physical problems (ß = + 25.0; p = 0.01), and social functioning (ß = + 19.2; p < 0.01) scales during the first three months in the exercise compared to the control group. No significant differences were observed between groups after six months. Exercise-based cardiac rehabilitation provided short-term improvements in the physical and mental aspects of QoL of patients with CCC.Trial registration: ClinicalTrials.gov Identifier: NCT02517632; August 7, 2015.

Impairment of health-related quality of life and its determinants among patients with podoconiosis in East Wollega Zone, Oromia Regional State, Ethiopia: institutional-based cross-sectional study.

OBJECTIVE: This study aimed to assess the impairment of health-related quality of life (HRQoL) and its determinants among patients diagnosed with podoconiosis in East Wollega Zone, Oromia Regional State, Ethiopia. METHODS: An institutional-based cross-sectional study design was used in the setting of primary healthcare facilities to assess impaired HRQoL among patients with podoconiosis in the East Wollega Zone from 1 March 2023 to 30 April 2023, using the Dermatologic Life Quality Index (DLQI). Data was collected from 494 patients with podoconiosis, and a multistage sampling technique was employed. The data was entered into EpiData V.4.6 and exported to SPSS V.27 for analysis. A linear regression model with a 95% cofidence interval (CI) was used to estimate level of HRQoL and to identify its determinants estimating beta (ß) coefficient declaring the significance level at p<0.05. RESULTS: The quality of life among patients was impaired on average by 9.6±6.1 with the lowest DLQI Score in the domain of treatment (0.8±0.97) and the highest in the domain of daily activity (2.3±1.72). The identified significant determinants of impairment of HRQoL associated with DLQI scores were duration of disease (95% CI, ß=0.11 (0.08 to 0.15)), acute dermato-lymphangio-adenitis (ADLA) (95% CI, ß=0.08 (0.01 to 0.16)), comorbidity (95% CI, ß=1.26 (0.37 to 2.16)), consistently wearing shoes (95% CI, ß=-0.06 (-0.09 to -0.03)), feeling of stigmatised (95% CI, ß=0.21 (0.16 to 0.25)) and psychological distress (95% CI, ß=0.17 (0.14 to 0.21)) and being female (95% CI, ß=1.16 (0.19 to 2.12)). CONCLUSION: Overall, HRQoL among patients with podoconiosis was moderately impaired. The duration of disease, ADLA, comorbidity, stigma, psychological distress and being female in sex significantly impaired HRQoL, whereas consistently wearing shoes significantly improved HRQoL among the patients with podoconiosis. Therefore, healthcare providers and public health experts should work on educating communities and counselling patients to avoid stigma and psychological distress, wearing shoes consistently and treating podoconiosis and other comorbidities among these patients.

Spatial-temporal distribution of visceral leishmaniasis in Rio de Janeiro, Brazil, 2001-2020: expansion and challenges.

BACKGROUND: Visceral leishmaniasis results from complex interactions among humans, dogs and environment. Brazil accounts for 97% of cases in the Americas. METHODS: Twenty years (2001-2020) of the endemic disease in the state of Rio de Janeiro were studied. Incidence, lethality, sociodemographic and clinical characteristics were investigated, complemented with spatial methodologies (kernel and clusters). RESULTS: Ninety-seven human cases and 625 dogs were reported. Of the 92 cities, 22 were human endemic areas. The state had a low incidence level (0.6 per 100 000). Lethality was higher compared with the Brazilian average. More than 90% of infections occurred in urban areas. Most cases (66%) occurred in men. The predominant age groups were 0-4 y (28.7%) and 20-39 y (32.9%). Fever (89.5%), splenomegaly (83.2%) and hepatomegaly (76.8%) were the main clinical manifestations. Spatial analysis showed a displacement of the human endemic: in the first decade (2001-2010), cases were concentrated in the Metropolitan region, and in the second decade (2011-2020) in the Médio Paraíba region of the state. Most of the endemic area (56.4%) had canine infections without reported human cases. CONCLUSIONS: Disorderly urbanisation and precarious living conditions favour the transmission of the disease. Changes in the environment and migratory processes contribute to its expansion.

An evaluation of mental health integration in the neglected tropical diseases program in Zamfara, North-west Nigeria.

BACKGROUND: Mental health and neglected tropical diseases (NTDs) are critical in healthcare systems, especially in low- and middle-income countries. Several policies are planned or designed by health stakeholders to address the mental health needs of people affected by NTDs. Still, the impact of such policies seems to be of no consequence. METHODS: The GAD-7 and PHQ-9 tools were used to determine the rate of depression and anxiety, respectively, among people affected by skin NTDs (leprosy and lymphatic filariasis [LF]) in Zamfara State, North-west Nigeria. The study also evaluated the barriers to the uptake of mental health services for people affected by skin NTDs in the state. We assessed 48 people affected by NTDs (leprosy, 32; lymphatic filariasis, 16) along with a corresponding 48 people who served as controls in the study. Qualitative interviews were carried out with the participants to elicit the barriers to mental health services for people affected by NTDs. Additionally, 48 selected healthcare workers from the state were assessed for their skills and capacity to offer mental health services. RESULTS: We found anxiety disorder present in 100% of the people living with LF and in 62% of the people living with leprosy. Depression was also found in 56% and 75% of the people living with leprosy and LF, respectively. An assessment of the barriers to the uptake of mental health services reveals that most people with NTDs are constrained by a lack of money to visit hospitals, the fear of stigmatisation and discrimination and long distances to health centres. Regarding the healthcare workers, the skills and capacity to offer mental health services were very low. CONCLUSIONS: We conclude that for mental health services to be integrated into the community health system for people with NTDs, there should be a concerted effort by all stakeholders and the intervention should be context specific instead of generalised. CONTEXTE: La santé mentale et les maladies tropicales négligées (MTN) sont des problématiques centrales dans la santé, en particulier dans les pays à revenu faible ou intermédiaire. Plusieurs politiques sont conçues par les acteurs de la santé publique pour répondre aux besoins de soins en santé mentale pour les personnes touchées par les MTN. Pourtant, le bilan reste mitigé quant à l'efficacité de ces soins. MÉTHODES: Les outils GAD-7 et PHQ-9 ont été utilisés pour déterminer le taux de dépression et d'anxiété chez les personnes atteintes de MTN cutanées (lèpre et filariose lymphatique) dans l'État de Zamfara, au nord-ouest du Nigeria. L'étude a également évalué les obstacles à l'utilisation des services de santé mentale pour les personnes atteintes de MTN cutanées dans l'État. Nous avons évalué 48 personnes atteintes de MTN (lèpre : 32, filariose lymphatique : 16) ainsi que 48 personnes correspondantes qui ont servi de témoins dans l'étude. Des entretiens qualitatifs ont été menés avec les participants afin d'identifier les obstacles aux services de santé mentale pour les personnes atteintes de MTN. En outre, 48 professionnels de la santé sélectionnés dans l'État ont été évalués pour déterminer leurs compétences et leur capacité à offrir des services de santé mentale. RÉSULTATS: Nous avons trouvé des troubles anxieux chez 100% des personnes atteintes de filariose lymphatique et chez 62% des personnes atteintes de lèpre. La dépression touche 56% et 75% des personnes vivant avec la lèpre et la filariose lymphatique respectivement. Une évaluation des obstacles à l'utilisation des services de santé mentale révèle que la plupart des personnes atteintes de MTN sont limitées par le manque d'argent pour se rendre à l'hôpital, la peur de la stigmatisation et de la discrimination, et les longues distances à parcourir pour se rendre dans les centres de santé. Les compétences et les capacités des professionnels de la santé à offrir des services de santé mentale sont très faibles. CONCLUSION: L'efficacité d'un protocole de soins pour les patients atteints de MTN (traitant la pathologie physique et d'éventuelles pathologies psychiatriques associées) nécessite une intégration des services de santé mentale dans le système de santé communautaire. ANTECEDENTES: La salud mental y las enfermedades tropicales desatendidas (ETDs), son fundamentales en los sistemas sanitarios, especialmente en los países de renta baja y media. Las partes interesadas en la sanidad planean o diseñan varias políticas para abordar las necesidades de salud mental de las personas afectadas por ETDs. Sin embargo, el impacto de dichas políticas parece ser nulo. MÉTODOS: Se utilizaron las herramientas GAD-7 y PHQ-9 para determinar la tasa de depresión y ansiedad, respectivamente, entre las personas afectadas por ETDs cutáneas (lepra y filariasis linfática) en el Estado de Zamfara, al noroeste de Nigeria. El estudio también evaluó las barreras para la aceptación de los servicios de salud mental por parte de las personas afectadas por ETDs cutáneas en el Estado. Se evaluó a 48 personas afectadas por ETDs (lepra: 32; filariasis linfática: 16) y a otras 48 que sirvieron de control en el estudio. Se llevaron a cabo entrevistas cualitativas con los participantes para determinar las barreras a los servicios de salud mental para las personas afectadas por ETDs. Además, se evaluaron las habilidades y la capacidad para ofrecer servicios de salud mental de 48 profesionales sanitarios del Estado. RESULTADOS: Encontramos trastorno de ansiedad presente en el 100% de las personas que vivían con filariasis linfática y en el 62% de las personas que vivían con lepra. También se encontró depresión en el 56% y el 75% de las personas que vivían con lepra y filariasis linfática respectivamente. Una evaluación de los obstáculos para la utilización de los servicios de salud mental revela que la mayoría de las personas con ETDs se ven limitadas por la falta de dinero para acudir a los hospitales, el miedo a la estigmatización, la discriminación y las largas distancias hasta los centros sanitarios. Por parte del personal sanitario, los conocimientos y la capacidad para ofrecer servicios de salud mental eran muy escasos. CONCLUSIONES: Para que los servicios de salud mental para personas con ETD se integren en el sistema sanitario comunitario, debe haber una concertación entre todas las partes interesadas y la intervención debe ser específica para cada contexto en lugar de generalizada.

Neglected Tropical Diseases: A Comprehensive Review.

Neglected tropical diseases (NTDs) are a group of diseases caused by diverse organisms, affecting millions of people in tropical and subtropical conditions. NTDs are more prevalent among people who live in poverty, without access to clean water, adequate sanitation, and quality health care. Most NTDs are chronic conditions and are potentially disablers than killers, leaving behind a trail of social consequences. Controlling NTDs has become complicated due to limited resources and are frequently ignored by global funding agencies. India experiences a significant burden of global NTDs. The paradox is that NTDs are preventable and treatable at an affordable cost. It then makes no sense as to why we co-exist with such diseases. The World Health Organization (WHO) has donned the leadership role of eliminating, eradicating, and controlling global NTDs. The WHO published a roadmap delineating a plan of action, which was being reviewed periodically. This led to substantive progress in tackling the NTDs. However, many challenges still exist to controlling and preventing NTDs. India has achieved significant progress towards NTD control and elimination by implementing the WHO strategies and action plans. This was evident by an increase in research and funding in this direction. The number of new drugs, vaccines, and investigative tools available and those in the pipeline is testimony to their efforts. Focusing singly on India's NTD problem would substantially reduce the burden of poverty-related neglected diseases and could dramatically advance the global health agenda. This review highlights the problem of NTDs in the Indian and global perspective.

Management of paediatric soil-transmitted helminthiasis in a non-endemic area: experience in a reference international health unit.

Soil-transmitted helminth (STH) infections inflict disability worldwide, especially in the poorest communities. Current therapeutic options against STHs show limited efficacy, particularly against Trichuris trichiura. The empirical management of patients coming from high-prevalence areas has been suggested for non-endemic areas. This study aimed to describe the management of STH infections in a non-endemic setting using an individualised approach. We performed a retrospective, descriptive study of all patients up to 16 years of age with STH infections attended at an international health unit in a non-endemic area (2014-2018), including all T. trichiura, Necator americanus, Ancylostoma duodenale, and Ascaris lumbricoides infections diagnosed using a formol-ether concentration technique and direct visualisation. Patients were treated according to current international guidelines. Sixty-one stool samples from 48 patients testing positive for STHs were collected, with 96% (46/48) reporting a previous long-term stay in endemic areas. Cure rates with 3-day benzimidazole regimens were 72% for T. trichiura, 40% for hookworms, and 83% for A. lumbricoides. The results were not influenced by any reinfection risk due to the study being performed in a non-endemic area. Patients coming from STH-endemic areas should be evaluated with appropriate diagnostic tools and followed up until cure control results. Cure rates in our cohort were moderate to low, similar to those published in studies in endemic areas. The efficacy of current treatment options is insufficient to recommend a specific empirical approach in high-income countries' healthcare systems.

Prevalence of trachoma in indigenous and non-indigenous areas, Northeastern Brazil, 2019-2021.

Objective: To estimate the prevalence of trachoma in indigenous and non-indigenous populations in selected areas of the state of Maranhão, in northeastern Brazil. Methods: This was a population-based survey with probabilistic sampling. For the diagnosis of trachoma, external ocular examination was performed using head magnifying loupes, at 2.5X magnification. The prevalence of trachomatous inflammation - follicular (TF) in children aged 1-9 years and the prevalence of trachomatous trichiasis (TT) in the population aged ≥15 years were estimated. Relative frequencies of sociodemographic and environmental characteristics were obtained. Results: The study included 7 971 individuals, 3 429 from non-indigenous populations and 4 542 from indigenous populations. The prevalence of TF in non-indigenous and indigenous populations was 0.1% and 2.9%, respectively, and the prevalence of TT among indigenous populations was 0.1%. Conclusions: The prevalence of TF and TT in the two evaluation units in the state of Maranhão were within the limits recommended for the elimination of trachoma as a public health problem. However, the prevalence of TF was higher in the indigenous evaluation unit, indicating a greater vulnerability of this population to the disease. The prevalence of TF of below 5.0% implies a reduction in transmission, which may have resulted from improved socioeconomic conditions and/or the implementation of the World Health Organization SAFE strategy.

Personalised human albumin in patients with cirrhosis and ascites: design and rationale for the ALB-TRIAL - a randomised clinical biomarker validation trial.

INTRODUCTION: Human albumin is used in the treatment of complications of cirrhosis. However, the use of long-term human albumin administration is costly and resource demanding for both patients and healthcare systems. A precision medicine approach with biomarkers to predict human albumin treatment response, so-called predictive biomarkers, could make this a viable treatment option in patients with cirrhosis and ascites. METHODS AND ANALYSIS: ALB-TRIAL is a multinational, double-blind, placebo-controlled randomised controlled trial. We aim to validate a predictive biomarker, consisting of a panel of circulating metabolites, to predict the treatment response to human albumin in patients with cirrhosis and ascites. All enrolled patients are stratified into a high-expected or low-expected effect stratum of human albumin based on the biomarker outcome. After stratification, patients in each group are randomised into either active treatment (20% human albumin) or corresponding placebo (0.9% NaCl) every 10th day for 6 months. The primary outcome is the cumulative number of liver-related events (composite of decompensation episodes, transjugular intrahepatic shunt insertion, liver transplantation and death). Key secondary outcomes include time-to-event analysis of primary outcome components, an analysis of the total healthcare burden and a health economic analysis. ETHICS AND DISSEMINATION: The trial obtained ethical and regulatory approval in Denmark, Germany, the Netherlands, Belgium, Hungary and Spain through the Clinical Trials Information System (CTIS) from 13 February 2023, while UK approvals from the Health Regulatory Authority, Medicines and Healthcare products Regulatory Agency and Research Ethics Committee are pending. Findings will be published in peer-reviewed journals, presented at conferences, communicated to relevant stakeholders and in the public registry of CTIS, following trial completion. TRIAL REGISTRATION NUMBER: NCT05056220 EU CT: 2022-501006-34-01.

Highly abundant bacteria in the gut of Triatoma dimidiata (Hemiptera: Reduviidae) can inhibit the growth of Trypanosoma cruzi (Kinetoplastea: Trypanosomatidae).

Chagas disease, caused by the protozoan Trypanosoma cruzi, is a zoonosis primarily found in rural areas of Latin America. It is considered a neglected tropical disease, and Triatoma dimidiata is the main vector of the parasite in Central America. Despite efforts, Chagas disease continues to be a public health concern, and vector control remains a primary tool to reduce transmission. In this study, we tested the hypothesis that highly abundant bacteria in the gut of T. dimidiata inhibit the growth of T. cruzi. To achieve this, bacterial diversity in the gut of T. dimidiata specimens from Costa Rica was characterized by metabarcoding of the 16S rRNA, microbial isolation was performed, and the effect of freeze-dried supernatants of the isolates on T. cruzi was investigated. Metabarcoding showed that the most abundant genera in the gut were Corynebacterium, Tsukamurella, Brevibacterium, and Staphylococcus. Barcoding and sequences comparison confirmed that 8 of the 30 most abundant amplicon sequence variants (ASVs) were isolated, and 2 of them showed an inhibitory effect on the growth of T. cruzi epimastigotes. These bacteria correspond to isolates of Tsukamurella and Brevibacterium, which were respectively the second and sixth most abundant ASVs in the gut of T. dimidiata. Notably, only the isolate of Brevibacterium showed a significant difference in growth inhibition against epimastigotes of both T. cruzi strains tested. These findings suggest that the gut microbiota of T. dimidiata may play an active role in modulating parasite development.

Pull me - push you? The disparate financing mechanisms of drug research in global health.

BACKGROUND: There is an inconsistency in the way pharmaceutical research is financed. While pull mechanisms are predominantly used to incentivize later-stage pharmaceutical research for products with demand in the Global North, so-called neglected diseases are chiefly financed by push funding. This discrepancy has so far been ignored in the academic debate, and any compelling explanation for why we draw the line between push and pull at poor people is lacking. MAIN BODY: Clinical development of new pharmaceuticals is chiefly financed by free market pull mechanisms. Even in cases where markets fail to deliver adequate incentives, demand enhancement mechanisms are used to replicate pull funding artificially, for example, with subscription models for antibiotics. Push funding in clinical research is almost always used when the poverty of patients means that markets fail to create sufficient demand. The general question of whether push or pull generally is the more efficient way to conduct pharmaceutical research arises. CONCLUSIONS: If the state is efficient in directing limited budgets for pharmaceutical research, push funding should be expanded to global diseases. If private industry is the more efficient actor, there would be enormous value in experimenting more aggressively with different approaches to enhance market demand artificially for neglected diseases.

Late-Stage Diversification of Pyrazoles as Antileishmanial Agents.

N-Pyrazolylcarboxamides and N-pyrazolylureas represent promising lead compounds for the development of novel antileishmanial drugs. Herein, we report the late-stage diversification of 3-bromopyrazoles 10 A/B and 14 A by Pd-catalyzed Sonogashira and Suzuki-Miyaura cross coupling reactions. The electron-withdrawing properties of the cyano moiety in 4-position of the pyrazole ring limited the acylation of the primary amino moiety in 5-position. A large set of pyrazoles bearing diverse aryl and alkynyl substituents in 3-position was prepared and the antileishmanial and antitrypanosomal activity was recorded. The urea 38 lacking the electron withdrawing cyano moiety in 4-position and containing the large 4-benzylpiperidinoo moiety exhibited a modest antileishmanial (IC50=19 µM) and antitrypanosomal activity (IC50=7.9 µM)). However, its considerable toxicity against the PMM and MRC-5 cells indicates low selectivity, i. e. a small gap between the desired antiparasitic activity and undesired cytotoxicity of <2- to 4-fold.

Unusual parasitoses in urban dogs: Urinary capillariosis and linguatulosis, cases report.

Parasitic diseases caused by uncommonly diagnosed parasites may pose a threat to companion animals' health in urban environments where they are least expected. The pentastomid Linguatula serrata (tongue worm) and the capillarid Pearsonema plica (syn. Capillaria plica) are parasites with an indirect life cycle, infecting both domestic and wild carnivores. The present report describes two cases: the first one of urinary capillariosis and the other of linguatulosis, in two dogs living in the urban environment of Athens, Greece. In the case of capillariosis, the dog never lived out of the city, so it was presumably infected in the urban environment. On the contrary, in the case of linguatulosis, the dog was adopted at a young age from a rural environment but remained asymptomatic for several months while living in the city. Both dogs had mild symptoms, compatible with these infections. Urinary capillariosis and linguatulosis are uncommon in owned, pet dogs, living in cities due to epizootiological characteristics, i.e. need for wildlife reservoir for P. plica and consumption of raw infected viscera for L. serrata. Different factors contribute to the fact that such infections may occur in scenarios where they are least expected. Recent studies show a progressive worldwide increase in the number of uncommon parasitoses in pet animals, that in some cases, such as linguatulosis, are of zoonotic relevance. Regular parasitological examinations and preventive antiparasitic schemes are necessary in order to treat and prevent infections in pet animals and safeguard the health of both animals and humans under the concept of One Health.

Nanotechnological approaches in the treatment of schistosomiasis: an overview.

Schistosomiasis causes over 200,000 deaths annually. The current treatment option, praziquantel, presents limitations, including low bioavailability and resistance. In this context, nanoparticles have emerged as a promising option for improving schistosomiasis treatment. Several narrative reviews have been published on this topic. Unfortunately, the lack of clear methodologies presented in these reviews leads to the exclusion of many important studies without apparent justification. This integrative review aims to examine works published in this area with a precise and reproducible method. To achieve this, three databases (i.e., Pubmed, Web of Science, and Scopus) were searched from March 31, 2022, to March 31, 2023. The search results included only original research articles that used nanoparticles smaller than 1 µm in the treatment context. Additionally, a search was conducted in the references of the identified articles to retrieve works that could not be found solely using the original search formula. As a result, 65 articles that met the established criteria were identified. Inorganic and polymeric nanoparticles were the most prevalent nanosystems used. Gold was the primary material used to produce inorganic nanoparticles, while poly(lactic-co-glycolic acid) and chitosan were commonly used to produce polymeric nanoparticles. None of these identified works presented results in the clinical phase. Finally, based on our findings, the outlook appears favorable, as there is a significant diversity of new substances with schistosomicidal potential. However, financial efforts are required to advance these nanoformulations.

Protocol for the challenge non-typhoidal Salmonella (CHANTS) study: a first-in-human, in-patient, double-blind, randomised, safety and dose-escalation controlled human infection model in the UK.

INTRODUCTION: Invasive non-typhoidal Salmonella (iNTS) serovars are a major cause of community-acquired bloodstream infections in sub-Saharan Africa (SSA). In this setting, Salmonella enterica serovar Typhimurium accounts for two-thirds of infections and is associated with an estimated case fatality rate of 15%-20%. Several iNTS vaccine candidates are in early-stage assessment which-if found effective-would provide a valuable public health tool to reduce iNTS disease burden. The CHANTS study aims to develop a first-in-human Salmonella Typhimurium controlled human infection model, which can act as a platform for future vaccine evaluation, in addition to providing novel insights into iNTS disease pathogenesis. METHODS AND ANALYSIS: This double-blind, safety and dose-escalation study will randomise 40-80 healthy UK participants aged 18-50 to receive oral challenge with one of two strains of S. Typhimurium belonging to the ST19 (strain 4/74) or ST313 (strain D23580) lineages. 4/74 is a global strain often associated with diarrhoeal illness predominantly in high-income settings, while D23580 is an archetypal strain representing invasive disease-causing isolates found in SSA. The primary objective is to determine the minimum infectious dose (colony-forming unit) required for 60%-75% of participants to develop clinical or microbiological features of systemic salmonellosis. Secondary endpoints are to describe and compare the clinical, microbiological and immunological responses following challenge. Dose escalation or de-escalation will be undertaken by continual-reassessment methodology and limited within prespecified safety thresholds. Exploratory objectives are to describe mechanisms of iNTS virulence, identify putative immune correlates of protection and describe host-pathogen interactions in response to infection. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the NHS Health Research Authority (London-Fulham Research Ethics Committee 21/PR/0051; IRAS Project ID 301659). The study findings will be disseminated in international peer-reviewed journals and presented at national/international stakeholder meetings. Study outcome summaries will be provided to both funders and participants. TRIAL REGISTRATION NUMBER: NCT05870150.

Empowering Riverine Communities in the Amazon: Strategies for Preventing Rabies.

Rabies, caused by the Lyssavirus genus, is a highly lethal zoonotic disease transmitted by animals such as bats and domestic and wild carnivores to humans, claiming nearly 100% of lives. In Brazil, recent evidence suggests an increasing role of bats in human deaths from rabies, particularly in the Amazon region. This neglected tropical disease disproportionately affects impoverished and vulnerable populations in rural areas, where approximately 80% of human cases are concentrated. This article presents research conducted in riverine communities of the Tapajós/Arapiuns Extractive Reserve in Brazil to combat rabies in September 2022. The study adopted a participatory and collaborative approach, involving community members, healthcare professionals, and educators. Prioritizing proactive interventions, the health team administered prophylactic vaccinations to 30 individuals residing in communities exposed to the Lyssavirus. Educational activities focused on dispelling myths and raising awareness about preventive measures, with 100% of individuals reporting prior doubts about the disease, emphasizing the essential nature of the clarification, especially regarding preventive aspects. This study underscores the importance of community involvement, personalized interventions, and ongoing education to effectively combat rabies. By reinforcing public health policies and promoting health education, we can empower communities to take proactive measures in rabies prevention, leading to a reduction in incidence and an improvement in quality of life.

Interaction between diterpene icetexanes and old yellow enzymes of Leishmania braziliensis and Trypanosoma cruzi.

Old Yellow Enzymes (OYEs) are flavin-dependent redox enzymes that promote the asymmetric reduction of activated alkenes. Due to the high importance of flavoenzymes in the metabolism of organisms, the interaction between OYEs from the parasites Trypanosoma cruzi and Leishmania braziliensis and three diterpene icetexanes (brussonol and two analogs), were evaluated in the present study, and differences in the binding mechanism and inhibition capacity of these molecules were examined. Although the aforementioned compounds showed poor and negligible activities against T. cruzi and L. braziliensis cells, respectively, the experiments with the purified enzymes indicated that the interaction occurs by divergent mechanisms. Overall, the ligands' inhibitory effect depends on their accessibility to the N5 position of the flavin's isoalloxazine ring. The results also indicated that the OYEs found in both parasites share structural similarities and showed affinities for the diterpene icetexanes in the same range. Nevertheless, the interaction between OYEs and ligands is directed by enthalpy and/or entropy in distinct ways. In conclusion, the binding site of both OYEs exhibits remarkable plasticity, and a large range of different molecules, including that can be substrates and inhibitors, can bind this site. This plasticity should be considered in drug design using OYE as a target.

Development and evaluation of the in vitro schistosomicidal activity of solid dispersions based on 2-(-5-bromo-1-H-indole-3-yl-methylene)-N-(naphthalene-1-ylhydrazine-carbothiamide.

Among all the neglected diseases, schistosomiasis is considered the second most important parasitic infection after malaria. Praziquantel is the most widely used drug for this disease, but its exclusive use may result in the development of drug-resistant schistosomiasis. To increase the control of the disease, new drugs have been developed as alternative treatments, among them 2-(-5-bromo-1-h-indole-3-yl-methylene)-N-(naphthalene-1-ylhydrazine-carbothiamide (LQIT/LT-50), which showed promising schistosomicidal activity in nonclinical studies. However, LQIT/LT-50 presents low solubility in water, resulting in reduced bioavailability. To overcome this solubility problem, the present study aimed to develop LQIT/LT-50 solid dispersions for the treatment of schistosomiasis. Solid dispersions were prepared through the solvent method using Soluplus©, polyethylene glycol (PEG) or polyvinylpyrrolidone (PVP K-30) as hydrophilic carriers. The formulations with the best results in the compatibility tests, aqueous solubility and preliminary stability studies have undergone solubility tests and physicochemical characterizations by Fourier-transform infrared spectroscopy (FTIR), x-ray diffractometry (XRD), exploratory differential calorimetry (DSC), thermogravimetry (TG) and Raman spectroscopy. Finally, the schistosomicidal activity was evaluated in vitro. The phycochemical analyzes showed that when using PVP K-30, there was an interaction between the PVP K-30 and LQIT/LT-50, proving the successful development of the solid dispersion. Furthermore, an increase in the solubility of the new system was observed (LQIT/LT-50:PVP K-30) in addition to the improvement in the in vitro shistosomidal activity at 1:4 (w/w) molar ratio (i.e., 20% drug loading) when compared to LQIT/LT-50 alone. The development of the LQIT/LT-50:PVP K-30 1:4 solid dispersion is encouraging for the future development of new pharmaceutical solid formulations, aiming the schistosomicidal treatment.