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1.
iScience ; 27(5): 109773, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38711445

ABSTRACT

Drug resistance threatens the effective control of infections, including parasitic diseases such as leishmaniases. Neutrophils are essential players in antimicrobial control, but their role in drug-resistant infections is poorly understood. Here, we evaluated human neutrophil response to clinical parasite strains having distinct natural drug susceptibility. We found that Leishmania antimony drug resistance significantly altered the expression of neutrophil genes, some of them transcribed by specific neutrophil subsets. Infection with drug-resistant parasites increased the expression of detoxification pathways and reduced the production of cytokines. Among these, the chemokine CCL3 was predominantly impacted, which resulted in an impaired ability of neutrophils to attract myeloid cells. Moreover, decreased myeloid recruitment when CCL3 levels are reduced was confirmed by blocking CCL3 in a mouse model. Collectively, these findings reveal that the interplay between naturally drug-resistant parasites and neutrophils modulates the infected skin immune microenvironment, revealing a key role of neutrophils in drug resistance.

2.
PLoS Negl Trop Dis ; 18(5): e0012156, 2024 May.
Article in English | MEDLINE | ID: mdl-38709850

ABSTRACT

The multifactorial basis of therapeutic response can obscure the relation between antimicrobial drug susceptibility and clinical outcome. To discern the relationship between parasite susceptibility to meglumine antimoniate (SbV) and therapeutic outcome of cutaneous leishmaniasis, risk factors for treatment failure were considered in evaluating this relationship in ninety-one cutaneous leishmaniasis patients and corresponding clinical strains of Leishmania (Viannia) panamensis. Parasite susceptibility to 32 µg SbV/mL (plasma Cmax) was evaluated in primary human macrophages, PBMCs, and U937 macrophages. Early parasitological response to treatment was determined in lesions of a subgroup of patients, and pathogenicity of Sb-resistant and sensitive clinical strains was compared in BALB/c mice. Parasite survival in cell models and patient lesions was determined by qRT-PCR of Leishmania 7SLRNA transcript. Parasite loads in BALB/c mice were quantified by limiting dilution analysis. The disparate Sb-susceptibility of parasite subpopulations distinguished by isoenzyme profiles (zymodemes) was manifest in all cell models. Notably, Sb-resistance defined by parasite survival, was most effectively discerned in U937 macrophages compared with primary human host cells, significantly higher among strains from patients who failed treatment than cured and, significantly associated with treatment failure. Each unit increase in transformed survival rate corresponded to a 10.6-fold rise in the odds of treatment failure. Furthermore, treatment failure was significantly associated with naturally Sb-resistant zymodeme 2.3 strains, which also produced larger lesions and parasite burdens in BALB/c mice than Sb-sensitive zymodeme 2.2 strains. The confounding effect of host risk factors for treatment failure in discerning this association was evidenced in comparing strains from patients with and without the defined risk factors for treatment failure. These results establish the association of natural resistance to meglumine antimoniate with treatment failure, the importance of host risk factors in evaluating drug susceptibility and treatment outcome, and the clinical and epidemiological relevance of natural Sb-resistance in L. (V.) panamensis subpopulations.


Subject(s)
Antiprotozoal Agents , Drug Resistance , Leishmaniasis, Cutaneous , Macrophages , Meglumine Antimoniate , Meglumine , Mice, Inbred BALB C , Organometallic Compounds , Treatment Failure , Animals , Leishmaniasis, Cutaneous/drug therapy , Leishmaniasis, Cutaneous/parasitology , Meglumine Antimoniate/therapeutic use , Meglumine Antimoniate/pharmacology , Humans , Antiprotozoal Agents/therapeutic use , Antiprotozoal Agents/pharmacology , Female , Meglumine/therapeutic use , Meglumine/pharmacology , Organometallic Compounds/therapeutic use , Organometallic Compounds/pharmacology , Mice , Macrophages/parasitology , Macrophages/drug effects , Macrophages/immunology , Male , Leishmania guyanensis/drug effects , Adult , Middle Aged , Young Adult , Parasite Load , Adolescent
3.
Am J Trop Med Hyg ; 110(3): 417-420, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38266289

ABSTRACT

Research capacity is a critical component of pandemic preparedness, as highlighted by the challenges faced during the Ebola outbreak in West Africa. Recent global initiatives, such as the Research & Development Task Force of the Global Health Security Agenda and the World Health Assembly's resolution on strengthening clinical trials, emphasize the need for robust research capabilities. This Perspective discusses the experiences of leaders in infectious disease research and capacity building in low- and middle-income countries, focusing on Colombia, Jamaica, and Pakistan. These case studies underscore the importance of collaborative efforts, interdisciplinary training, and global partnerships in pandemic response. The experiences highlight the necessity for rapid pathogen identification, capacity for genomic sequencing, and proactive engagement with policymakers. Challenges faced, including the shortage of trained staff and reliance on imported reagents, emphasize the ongoing need for building research capacity.


Subject(s)
Hemorrhagic Fever, Ebola , Pandemic Preparedness , Humans , Developing Countries , Disease Outbreaks , Hemorrhagic Fever, Ebola/epidemiology , Hemorrhagic Fever, Ebola/prevention & control , Global Health
4.
Am J Trop Med Hyg ; 109(4): 778-790, 2023 10 04.
Article in English | MEDLINE | ID: mdl-37640290

ABSTRACT

Cutaneous leishmaniasis (CL) remains a global health problem. Compelled by the protracted healing process, initial and final outcomes of treatment are determined at 90 and 180 days, respectively, after initiation of treatment. Loss to follow-up during these intervals is substantial. Consequently, the effectiveness of treatment is largely unknown. We conducted an effectiveness-implementation hybrid design study of a community-based mobile health (mHealth) strategy to monitor adherence to anti-leishmanial treatment, adverse drug reactions, and therapeutic response compared with standard of care in two rural communities of Colombia. Three implementation outcomes were evaluated: usability and acceptability by qualitative methods and fidelity using quantitative methods. Fifty-seven patients were prospectively included in the mHealth intervention and 48 in the standard-of-care group. In addition, 24 community health leaders (CHLs), health workers, and patients participated in qualitative evaluations. The intervention significantly increased the proportion of patients having follow-up of therapeutic outcomes 90 and 180 days after initiating treatment from 4.2% (standard of care) to 82.5% (intervention), P < 0.001. The proportion of patients having records of treatment adherence, adverse drug reactions, and therapeutic response also increased significantly (P < 0.001). Fidelity to the intervention (recording of treatment adherence, adverse drug reactions, lesion photographs, and evaluation of therapeutic response) was 70-100%. The app was highly accepted by CHLs, health workers, and patients, who perceived that the app improved case identification and follow-up and met a public health need. Although usability was high, low connectivity affected real-time transmission of data. This community-based mHealth strategy facilitated access to health care for CL in rural areas and knowledge of treatment effectiveness.


Subject(s)
Drug-Related Side Effects and Adverse Reactions , Leishmaniasis, Cutaneous , Telemedicine , Humans , Telemedicine/methods , Delivery of Health Care , Treatment Outcome , Leishmaniasis, Cutaneous/diagnosis , Leishmaniasis, Cutaneous/drug therapy
5.
PLoS Negl Trop Dis ; 17(3): e0011180, 2023 03.
Article in English | MEDLINE | ID: mdl-36972285

ABSTRACT

BACKGROUND: In Latin America, cutaneous leishmaniasis primarily affects dispersed rural communities, that have limited access to the public health system and medical attention. Mobile health (mHealth) strategies have shown potential to improve clinical management and epidemiological surveillance of neglected tropical diseases, particularly those of the skin. METHODS: The Guaral +ST app for Android was designed to monitor cutaneous leishmaniasis treatment and assess therapeutic response. We carried out a randomized trial in the coastal municipality of Tumaco in southwestern Colombia, with parallel arms comparing a) follow-up aided by the app to b) standard institution-based follow-up. Treatment was prescribed according to national guidelines. Follow-up of therapeutic response was scheduled at the end of treatment and at 7, 13 and 26 weeks after the start of treatment. The primary endpoint was the proportion of participants who were monitored at or around week 26, allowing outcome and effectiveness of treatment to be determined. RESULTS: Follow-up of treatment and outcome assessment was achieved in significantly more patients in the intervention arm than the controls, Of the 75 participants in the two randomized arms, 74 had information on whether or not treatment was followed and outcome determined at or around week 26. Among these, 26/49 (53.1%) were evaluated in the intervention arm, and none (0/25, 0%) in the control arm (difference = 53.1%, 95% confidence interval 39.1-67.0%, p<0.001). Of the 26 participants evaluated at or around week 26 in the intervention arm, 22 (84.6%) had cured. There were no serious adverse events, nor events of severe intensity among patients monitored by CHW using the app. CONCLUSION: This study provides proof of concept for mHealth to monitor treatment of CL in remote and complex settings, deliver improved care and to provide information to the health system on the effectiveness of treatment as it is delivered to affected populations. CLINICAL TRIAL REGISTRATION: ISRCTN54865992.


Subject(s)
Leishmaniasis, Cutaneous , Telemedicine , Humans , Rural Population , Colombia/epidemiology , Follow-Up Studies , Leishmaniasis, Cutaneous/diagnosis , Leishmaniasis, Cutaneous/epidemiology , Leishmaniasis, Cutaneous/therapy
6.
PLoS Negl Trop Dis ; 17(1): e0011029, 2023 01.
Article in English | MEDLINE | ID: mdl-36689465

ABSTRACT

BACKGROUND: Treatment guidance for children and older adult patients affected by cutaneous leishmaniasis (CL) is unclear due to limited representation of these groups in clinical trials. METHODS: We conducted a collaborative retrospective study to describe the effectiveness and safety of antileishmanial treatments in children ≤ 10 and adults ≥ 60 years of age, treated between 2014 and 2018 in ten CL referral centers in Latin America. RESULTS: 2,037 clinical records were assessed for eligibility. Of them, the main reason for non-inclusion was lack of data on treatment follow-up and therapeutic response (182/242, 75% of children and 179/468, 38% of adults). Data on 1,325 eligible CL patients (736 children and 589 older adults) were analyzed. In both age groups, disease presentation was mild, with a median number of lesions of one (IQR: 1-2) and median lesion diameter of less than 3 cm. Less than 50% of the patients had data for two or more follow-up visits post-treatment (being only 28% in pediatric patients). Systemic antimonials were the most common monotherapy regimen in both age groups (590/736, 80.2% of children and 308/589, 52.3% of older adults) with overall cure rates of 54.6% (95% CI: 50.5-58.6%) and 68.2% (95% CI: 62.6-73.4%), respectively. Other treatments used include miltefosine, amphotericin B, intralesional antimonials, and pentamidine. Adverse reactions related to the main treatment were experienced in 11.9% (86/722) of children versus 38.4% (206/537) of older adults. Most adverse reactions were of mild intensity. CONCLUSION: Our findings support the need for greater availability and use of alternatives to systemic antimonials, particularly local therapies, and development of strategies to improve patient follow-up across the region, with special attention to pediatric populations.


Subject(s)
Antiprotozoal Agents , Leishmaniasis, Cutaneous , Humans , Child , Aged , Retrospective Studies , Leishmaniasis, Cutaneous/drug therapy , Pentamidine , Treatment Outcome
7.
Pathogens ; 11(3)2022 Mar 21.
Article in English | MEDLINE | ID: mdl-35335703

ABSTRACT

Addition of the immunomodulator pentoxifylline (PTX) to antimonial treatment of mucosal leishmaniasis has shown increased efficacy. This randomized, double-blind, placebo-controlled trial evaluated whether addition of pentoxifylline to meglumine antimoniate (MA) treatment improves therapeutic response in cutaneous leishmaniasis (CL) patients. Seventy-three patients aged 18−65 years, having multiple lesions or a single lesion ≥ 3 cm were randomized to receive: intramuscular MA (20 mg/kg/day × 20 days) plus oral PTX 400 mg thrice daily (intervention arm, n = 36) or MA plus placebo (control arm, n = 37), between 2012 and 2015. Inflammatory gene expression was evaluated by RT-qPCR in peripheral blood mononuclear cells from trial patients, before and after treatment. Intention-to-treat failure rate was 35% for intervention vs. 25% for control (OR: 0.61, 95% CI: 0.21−1.71). Per-protocol failure rate was 32% for PTX, and 24% for placebo (OR: 0.50, 95% CI: 0.13−1.97). No differences in frequency or severity of adverse events were found (PTX = 142 vs. placebo = 140). Expression of inflammatory mediators was unaltered by addition of PTX to MA. However, therapeutic failure was associated with significant overexpression of il1ß and ptgs2 (p < 0.05), irrespective of study group. No clinical benefit of addition of PTX to standard treatment was detected in early mild to moderate CL caused by Leishmania (V.) panamensis.

8.
Lancet Reg Health Am ; 9: 100195, 2022 May.
Article in English | MEDLINE | ID: mdl-35156075

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to cause very high morbidity and mortality throughout Latin American countries. However, few population-based seroprevalence surveys have been conducted to quantify attack rates and characterize drivers of transmission. METHODS: We conducted a population-based cross-sectional study to assess the seroprevalence of antibodies against SARS-CoV-2 in ten cities in Colombia between September and December 2020. The study involved multi-stage cluster sampling at each city. Participants provided a serum sample and answered a demographic and risk factor questionnaire. Prior infection by SARS-CoV-2 was ascertained using the "SARS-CoV-2 Total (COV2T) Advia Centaur - Siemens" chemiluminescence assay. FINDINGS: A total of 17863 participants from 7320 households participated in the study. Seroprevalence varied substantially between cities, ranging from 26% (95%CI 23-29 %) in Medellín to 68% (95%CI 62-74 %) in Guapi. There were no differences in seroprevalence by sex, but seropositivity was higher in certain ethnic groups. There was substantial heterogeneity in seroprevalence within cities, driven to a large extent by a strong association between socioeconomic stratum and seropositivity. INTERPRETATION: Colombia has been one of the Latin American countries most affected by the COVID-19 pandemic. This study documented very high attack rates in several Colombian cities by the end of 2020 and identified key drivers of heterogeneities including ethnicity and socioeconomic stratum. Few studies of seroprevalence of SARS-CoV-2 have been conducted in Latin America, and therefore this study contributes to the fundamental understanding of the pandemic in the region. FUNDING: The study was sponsored by, Ministerio de Ciencia y Tecnología e Innovación -CT361/2020, Ministerio de Salud y Protección Social, Fundación Universitaria del Norte, Imperial College of London, Universidad Nacional de Colombia (Sede Medellín), Universidad de Córdoba, California University, Unidad Nacional de Gestión del Riesgo, Centro de Atención y Diagnóstico de Enfermedades Infecciosas -CDI-, Centro Internacional de Entrenamiento e Investigaciones Médicas -CIDEIM-, Departamento Administrativo Nacional de Estadística - DANE, Fondo Nacional de Turismo -FONTUR-, Secretarías de Salud Departamentales, Distritales y Municipales and Instituto Nacional de Salud.

9.
Antimicrob Agents Chemother ; 66(1): e0142521, 2022 01 18.
Article in English | MEDLINE | ID: mdl-34694879

ABSTRACT

Failure of treatment of cutaneous leishmaniasis with antimonial drugs and miltefosine is frequent. Use of oral combination therapy represents an attractive strategy to increase efficacy of treatment and reduce the risk of drug resistance. We evaluated the potency of posaconazole, itraconazole, voriconazole, and fluconazole and the potential synergy of those demonstrating the highest potency, in combination with miltefosine (HePC), against infection with Leishmania (Viannia) panamensis. Synergistic activity was determined by isobolograms and calculation of the fractional inhibitory concentration index (FICI), based on parasite quantification using an ex vivo model of human peripheral blood mononuclear cells (PBMCs) infected with a luciferase-transfected, antimony and miltefosine sensitive line of L. panamensis. The drug combination and concentrations that displayed synergy were then evaluated for antileishmanial effect in 10 clinical strains of L. panamensis by reverse transcription-quantitative (qRT-PCR) of Leishmania 7SLRNA. High potency was substantiated for posaconazole and itraconazole against sensitive as well as HePC- and antimony-resistant lines of L. panamensis, whereas fluconazole and voriconazole displayed low potency. HePC combined with posaconazole (Poz) demonstrated evidence of synergy at free drug concentrations achieved in plasma during treatment (2 µM HePC plus 4 µM Poz). FICI, based on 70% and 90% reduction of infection, was 0.5 for the sensitive line. The combination of 2 µM HePC plus 4 µM Poz effected a significantly greater reduction of infection by clinical strains of L. panamensis than individual drugs. Orally administrable miltefosine/posaconazole combinations demonstrated synergistic antileishmanial capacity ex vivo against L. panamensis, supporting their potential as a novel therapeutic strategy to improve efficacy and effectiveness of treatment.


Subject(s)
Antiprotozoal Agents , Leishmania guyanensis , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/therapeutic use , Azoles/pharmacology , Humans , Leukocytes, Mononuclear , Phosphorylcholine/analogs & derivatives , Phosphorylcholine/therapeutic use
10.
Front Cell Infect Microbiol ; 11: 710006, 2021.
Article in English | MEDLINE | ID: mdl-34631596

ABSTRACT

Emerging evidence indicates that innate host response contributes to the therapeutic effect of antimicrobial medications. Recent studies have shown that Leishmania parasites derived by in vitro selection for resistance to pentavalent antimony (SbV) as meglumine antimoniate (MA) modulate the activation of neutrophils. However, whether modulation of neutrophil activation extends to natural resistance to this antileishmanial drug has not been established. We have evaluated the influence of clinical strains of L. (V.) panamensis having intrinsic tolerance/resistance to SbV, on the inflammatory response of neutrophils during ex vivo exposure to MA. Accordingly, neutrophils obtained from healthy donors were infected with clinical strains that are sensitive (n = 10) or intrinsically tolerant/resistant to SbV (n = 10) and exposed to a concentration approximating the maximal plasma concentration (Cmax) of SbV (32 µg/ml). The activation profile of neutrophils was evaluated as the expression of the surface membrane markers CD66b, CD18, and CD62L by flow cytometry, measurement of reactive oxygen species (ROS) by luminometry, and NET formation using Picogreen to measure dsDNA release and quantification of NETs by confocal microscopy. These parameters of activation were analyzed in relation with parasite susceptibility to SbV and exposure to MA. Here, we show that clinical strains presenting intrinsic tolerance/resistance to SbV induced significantly lower ROS production compared to drug-sensitive clinical strains, both in the presence and in the absence of MA. Likewise, analyses of surface membrane activation markers revealed significantly higher expression of CD62L on cells infected with intrinsically SbV tolerant/resistant L. (V.) panamensis than cells infected with drug-sensitive strains. Expression of other activation markers (CD18 and CD66b) and NET formation were similar for neutrophils infected with SbV sensitive and tolerant clinical strains under the conditions evaluated. Exposure to MA broadly impacted the activation of neutrophils, diminishing NET formation and the expression of CD62L, while augmenting ROS production and CD66b expression, independently of the parasite susceptibility phenotype. These results demonstrated that activation of human neutrophils ex vivo is differentially modulated by infection with clinical strains of L. (V.) panamensis having intrinsic tolerance/resistance to SbV compared to sensitive strains, and by exposure to antimonial drug.

11.
PLoS Negl Trop Dis ; 15(4): e0009291, 2021 04.
Article in English | MEDLINE | ID: mdl-33909619

ABSTRACT

BACKGROUND: Control of cutaneous leishmaniasis by public health systems in the Americas relies on case identification and treatment. Point-of-care diagnostics that can be performed by health workers within or near affected communities could effectively bring the health system to the resource-limited sites providing early diagnosis and treatment, reducing morbidity and the burden of disease. METHODOLOGY/PRINCIPAL FINDINGS: A cross-sectional study was undertaken to evaluate the diagnostic test performance of Isothermal Recombinase Polymerase Amplification (RPA) targeting Leishmania kinetoplast DNA, coupled with a lateral flow (LF) immunochromatographic strip, in a field setting and a laboratory reference center. Minimally invasive swab and FTA filter paper samples were obtained by community health workers and highly trained technicians from ulcerated lesions of > 2 weeks' evolution from 118 patients' ≥ 2 years of age in the municipality of Tumaco, Nariño. Extracted DNA was processed by RPA-LF at a reference center or in a primary health facility in the field. Evaluation was based on a composite "gold standard" that included microscopy, culture, biopsy and real-time polymerase chain reaction detection of Leishmania 18S rDNA. Standard of care routine diagnostic tests were explored as comparators. Sensitivity and specificity of RPA-LF in the reference lab scenario were 87% (95%CI 74-94) and 86% (95%CI 74-97), respectively. In the field scenario, the sensitivity was 75% (95%CI 65-84) and specificity 89% (95%CI 78-99). Positive likelihood ratios in both scenarios were higher than 6 while negative likelihood ratios ranged to 0.2-0.3 supporting the usefulness of RPA-LF to rule-in and potentially to rule-out infection. CONCLUSIONS/SIGNIFICANCE: The low complexity requirements of RPA-LF combined with non-invasive sampling support the feasibility of its utilization by community health workers with the goal of strengthening the diagnostic capacity for cutaneous leishmaniasis in Colombia. TRIAL REGISTRATION: ClinicalTrials.gov NCT04500873.


Subject(s)
Leishmania/genetics , Leishmania/isolation & purification , Leishmaniasis, Cutaneous/diagnosis , Molecular Diagnostic Techniques/methods , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Chromatography, Affinity , Colombia , Cross-Sectional Studies , DNA Primers/genetics , DNA, Kinetoplast/genetics , DNA, Protozoan/genetics , Female , Humans , Male , Middle Aged , Nucleic Acid Amplification Techniques , Sensitivity and Specificity , Young Adult
12.
PLoS Negl Trop Dis ; 15(2): e0008989, 2021 02.
Article in English | MEDLINE | ID: mdl-33571192

ABSTRACT

BACKGROUND: Detection and management of neglected tropical diseases such as cutaneous leishmaniasis present unmet challenges stemming from their prevalence in remote, rural, resource constrained areas having limited access to health services. These challenges are frequently compounded by armed conflict or illicit extractive industries. The use of mobile health technologies has shown promise in such settings, yet data on outcomes in the field remain scarce. METHODS: We adapted a validated prediction rule for the presumptive diagnosis of CL to create a mobile application for use by community health volunteers. We used human-centered design practices and agile development for app iteration. We tested the application in three rural areas where cutaneous leishmaniasis is endemic and an urban setting where patients seek medical attention in the municipality of Tumaco, Colombia. The application was assessed for usability, sensitivity and inter-rater reliability (kappa) when used by community health volunteers (CHV), health workers and a general practitioner, study physician. RESULTS: The application was readily used and understood. Among 122 screened cases with cutaneous ulcers, sensitivity to detect parasitologically proven CL was >95%. The proportion of participants with parasitologically confirmed CL was high (88%), precluding evaluation of specificity, and driving a high level of crude agreement between the app and parasitological diagnosis. The chance-adjusted agreement (kappa) varied across the components of the risk score. Time to diagnosis was reduced significantly, from 8 to 4 weeks on average when CHV conducted active case detection using the application, compared to passive case detection by health facility-based personnel. CONCLUSIONS: Translating a validated prediction rule to a mHealth technology has shown the potential to improve the capacity of community health workers and healthcare personnel to provide opportune care, and access to health services for underserved populations. These findings support the use of mHealth tools for NTD research and healthcare.


Subject(s)
Early Diagnosis , Leishmaniasis, Cutaneous/diagnosis , Mobile Applications , Tropical Medicine/methods , Adaptation, Physiological , Adolescent , Adult , Colombia/epidemiology , Community Health Workers , Female , Humans , Leishmaniasis, Cutaneous/epidemiology , Male , Mass Screening/methods , Medically Underserved Area , Reproducibility of Results , Tropical Medicine/instrumentation , Young Adult
13.
Clin Infect Dis ; 72(10): e484-e492, 2021 05 18.
Article in English | MEDLINE | ID: mdl-32818964

ABSTRACT

BACKGROUND: Control of cutaneous leishmaniasis (CL) relies on chemotherapy, yet gaps in our understanding of the determinants of therapeutic outcome impede optimization of antileishmanial drug regimens. Pharmacodynamic (PD) parameters of antimicrobials are based on the relationship between drug concentrations/exposure and microbial kill. However, viable Leishmania persist in a high proportion of individuals despite clinical resolution, indicating that determinants other than parasite clearance are involved in drug efficacy. METHODS: In this study, the profiles of expression of neutrophils, monocytes, Th1 and Th17 gene signatures were characterized in peripheral blood mononuclear cells (PBMCs) during treatment with meglumine antimoniate (MA) and clinical cure of human CL caused by Leishmania (Viannia). We explored relationships of immune gene expression with plasma and intracellular antimony (Sb) concentrations. RESULTS: Our findings show a rapid and orchestrated modulation of gene expression networks upon exposure to MA. We report nonlinear pharmacokinetic/pharmacodynamic (PK/PD) relationships of Sb and gene expression dynamics in PBMCs , concurring with a time lag in the detection of intracellular drug concentrations and with PK evidence of intracellular Sb accumulation. CONCLUSIONS: Our results quantitatively portray the immune dynamics of therapeutic healing, and provide the knowledge base for optimization of antimonial drug treatments, guiding the selection and/or design of targeted drug delivery systems and strategies for targeted immunomodulation.


Subject(s)
Antiprotozoal Agents , Leishmania , Leishmaniasis, Cutaneous , Antiprotozoal Agents/therapeutic use , Humans , Leishmaniasis, Cutaneous/drug therapy , Leukocytes, Mononuclear , Meglumine Antimoniate/therapeutic use
14.
Rev Panam Salud Publica ; 44: e77, 2020.
Article in English | MEDLINE | ID: mdl-32774348

ABSTRACT

Universal health coverage is a public health priority in the Americas. Social innovation in health offers novel solutions to unmet needs, by enabling health care delivery to be more inclusive, affordable, and effective. In 2017, an international collaborative consortium launched an open call for solutions that sought to identify social innovations in health in Central America and the Caribbean. The focus was set on how these solutions can strengthen health care delivery, with emphasis on reducing the impact of neglected transmissible diseases. A crowdsourcing strategy was implemented to identify social innovations in health. These were evaluated by an external panel of experts and practitioners and civil society representing the health and social innovation sectors, based on the appropriateness, innovativeness, and affordability of the solution. The three top-scoring solutions were analyzed through case studies including site visits by a team of investigators. Two key findings emerged from the response to the call: 1) innovative solutions were based on the knowledge and experience of individuals and communities facing adverse situations; 2) this knowledge was shared through health promotion and education, leading to empowerment of the communities. The principal challenges addressed by the solutions were the limited access to quality health care services and failed traditional strategies for vector control. The solutions identified demonstrated how social innovation can strengthen health systems by delivering novel solutions to health needs and articulating communities to enable them to work hand-in-hand with the health system toward universal health.


La cobertura universal de salud es una prioridad de salud pública en la Región de las Américas. La innovación social en materia de salud ofrece soluciones novedosas a las necesidades insatisfechas, al permitir que la prestación de servicios de salud sea más inclusiva, asequible y eficaz. En 2017, un consorcio de colaboración internacional lanzó una convocatoria abierta de soluciones con el fin de identificar innovaciones sociales en materia de salud en América Central y el Caribe. Esta se centró en la forma en que esas soluciones pueden fortalecer la prestación de atención sanitaria, con énfasis en la reducción de los efectos de las enfermedades transmisibles desatendidas. Para identificar las innovaciones sociales en materia de salud se aplicó una estrategia de colaboración masiva (crowdsourcing). Las propuestas fueron evaluadas por un grupo externo conformado por expertos, profesionales y la sociedad civil que representaban a los sectores de la salud y la innovación social, sobre la base de la idoneidad, la capacidad de innovación y la asequibilidad de la solución. Se analizaron las tres soluciones mejor calificadas mediante estudios de casos que incluyeron visitas al lugar por parte de un equipo de investigadores. De la respuesta a la convocatoria surgieron dos conclusiones clave: 1) las soluciones innovadoras se basaron en el conocimiento y la experiencia de las personas y las comunidades que se enfrentaban a situaciones adversas, y 2) este conocimiento se compartió a través de actividades de promoción de la salud y educación, lo que condujo al empoderamiento de las comunidades. Los principales problemas que abordaron las soluciones fueron el acceso limitado a servicios de atención sanitaria de calidad y el fracaso de las estrategias tradicionales de control de vectores. Las soluciones identificadas demostraron cómo la innovación social puede fortalecer los sistemas de salud proporcionando soluciones novedosas a las necesidades de salud y apoyando a las comunidades para que puedan colaborar estrechamente con el sistema de salud hacia la salud universal.

15.
Article in English | PAHO-IRIS | ID: phr-52527

ABSTRACT

[ABSTRACT]. Universal health coverage is a public health priority in the Americas. Social innovation in health offers novel solutions to unmet needs, by enabling health care delivery to be more inclusive, affordable, and effective. In 2017, an international collaborative consortium launched an open call for solutions that sought to identify social innovations in health in Central America and the Caribbean. The focus was set on how these solutions can strengthen health care delivery, with emphasis on reducing the impact of neglected transmissible diseases. A crowdsourcing strategy was implemented to identify social innovations in health. These were evaluated by an external panel of experts and practitioners and civil society representing the health and social innovation sectors, based on the appropriateness, innovativeness, and affordability of the solution. The three top-scoring solutions were analyzed through case studies including site visits by a team of investigators. Two key findings emerged from the response to the call: 1) innovative solutions were based on the knowledge and experience of individuals and communities facing adverse situations; 2) this knowledge was shared through health promotion and education, leading to empowerment of the communities. The principal challenges addressed by the solutions were the limited access to quality health care services and failed traditional strategies for vector control. The solutions identified demonstrated how social innovation can strengthen health systems by delivering novel solutions to health needs and articulating communities to enable them to work hand-in-hand with the health system toward universal health.


[RESUMEN]. La cobertura universal de salud es una prioridad de salud pública en la Región de las Américas. La innovación social en materia de salud ofrece soluciones novedosas a las necesidades insatisfechas, al permitir que la prestación de servicios de salud sea más inclusiva, asequible y eficaz. En 2017, un consorcio de colaboración internacional lanzó una convocatoria abierta de soluciones con el fin de identificar innovaciones sociales en materia de salud en América Central y el Caribe. Esta se centró en la forma en que esas soluciones pueden fortalecer la prestación de atención sanitaria, con énfasis en la reducción de los efectos de las enfermedades transmisibles desatendidas. Para identificar las innovaciones sociales en materia de salud se aplicó una estrategia de colaboración masiva (crowdsourcing). Las propuestas fueron evaluadas por un grupo externo conformado por expertos, profesionales y la sociedad civil que representaban a los sectores de la salud y la innovación social, sobre la base de la idoneidad, la capacidad de innovación y la asequibilidad de la solución. Se analizaron las tres soluciones mejor calificadas mediante estudios de casos que incluyeron visitas al lugar por parte de un equipo de investigadores. De la respuesta a la convocatoria surgieron dos conclusiones clave: 1) las soluciones innovadoras se basaron en el conocimiento y la experiencia de las personas y las comunidades que se enfrentaban a situaciones adversas, y 2) este conocimiento se compartió a través de actividades de promoción de la salud y educación, lo que condujo al empoderamiento de las comunidades. Los principales problemas que abordaron las soluciones fueron el acceso limitado a servicios de atención sanitaria de calidad y el fracaso de las estrategias tradicionales de control de vectores. Las soluciones identificadas demostraron cómo la innovación social puede fortalecer los sistemas de salud proporcionando soluciones novedosas a las necesidades de salud y apoyando a las comunidades para que puedan colaborar estrechamente con el sistema de salud hacia la salud universal.


Subject(s)
Neglected Diseases , Delivery of Health Care , Social Participation , Central America , Caribbean Region , Neglected Diseases , Delivery of Health Care , Social Participation , Central America , Caribbean Region
17.
Infect Immun ; 88(3)2020 02 20.
Article in English | MEDLINE | ID: mdl-31818959

ABSTRACT

The immune mechanisms that contribute to the efficacy of treatment of cutaneous leishmaniasis (CL) are not fully understood. The aim of this study was to define immune correlates of the outcome of treatment of CL caused by Leishmania (Viannia) species during standard of care treatment with pentavalent antimonials. We conducted a comparative expression profiling of immune response genes in peripheral blood mononuclear cells (PBMCs) and lesion biopsy specimens obtained from CL patients before and at the end of treatment (EoT) with meglumine antimoniate. The ex vivo response of PBMCs to L (V) panamensis partially reflected that of lesion microenvironments. Significant downregulation of gene expression profiles consistent with local innate immune responses (monocyte and neutrophil activation and chemoattractant molecules) was observed at EoT in biopsy specimens of patients who cured (n = 8), compared to those from patients with treatment failure (n = 8). Among differentially expressed genes, pretreatment expression of CCL2 was significantly predictive of the therapeutic response (receiver operating characteristic [ROC] curve, area under the curve [AUC] = 0.82, P = 0.02). Polymorphisms in regulatory regions of the CCL2 promoter were analyzed in a pilot cohort of DNA samples from CL patients (cures, n = 20, and treatment failure, n = 20), showing putative association of polymorphisms rs13900(C/T) and rs2857656(G/C) with treatment outcome. Our data indicate that dampening gene expression profiles of monocyte and neutrophil activation characterize clinical cure after treatment of CL, supporting participation of parasite-sustained inflammation or deregulated innate immune responses in treatment failure.


Subject(s)
Antiprotozoal Agents/therapeutic use , Cytokines/metabolism , Immunity, Innate/physiology , Leishmania/immunology , Leishmaniasis/drug therapy , Leishmaniasis/immunology , Meglumine Antimoniate/therapeutic use , Gene Expression Profiling , Humans , Leishmaniasis/metabolism , Leukocytes, Mononuclear/metabolism , Monocyte Chemoattractant Proteins/metabolism , Monocytes/metabolism
19.
Article in Spanish, Portuguese | PAHO-IRIS | ID: phr-51084

ABSTRACT

[EXTRACTO]. Actualmente se presta cada vez más atención a los determinantes políticos, económicos, ambientales y sociales de la salud. Esto ha generado una mayor demanda de investigación para la salud a nivel mundial que incluya a los países de ingresos bajos y medianos, con objeto de alcanzar los objetivos de desarrollo sostenible de las Naciones Unidas. Además del financiamiento, se necesitan suficientes recursos humanos e infraestructura para que estos países lleguen a ser asociados en un plano de igualdad con las instituciones de investigación internacionalmente reconocidas de los países de ingresos altos que establecen las agendas de investigación, y para garantizar que el programa de investigación mundial refleje sus necesidades. Las limitaciones en la capacidad de investigación y las grandes disparidades existentes entre los países de ingresos altos y los de ingresos bajos y medianos en cuanto a su capacidad de producir y usar la investigación para la salud han contribuido a producir una falta de evidencia que permita fundamentar la práctica clínica y orientar las políticas sanitarias regionales y mundiales. Esto ha perpetuado las desigualdades en la salud...


[EXTRACTO]. Existe atualmente um maior reconhecimento dos determinantes políticos, econômicos, ambientais e sociais da saúde. A consequência disso foi um aumento da demanda por pesquisa em saúde global, com participação dos países de baixa e média renda, para cumprir os objetivos de desenvolvimento sustentável das Nações Unidas. Além de financiamento, são necessários recursos humanos e infraestrutura suficientes para que esses países se tornem parceiros em igualdade de condições com instituições de pesquisa internacionalmente reconhecidas em países de alta renda que definem as agendas de pesquisa e cuidam para que o programa global de pesquisa em saúde reflita suas necessidades. A limitada capacidade de pesquisa e as grandes disparidades entre países de alta renda e países de baixa e média renda no tocante à capacidade de produzir e usar pesquisas para a saúde contribuíram para a falta de evidências para informar a prática e orientar as políticas de saúde regionais e globais, o que perpetuou as desigualdades em saúde...


Subject(s)
Health Services Research , Social Determinants of Health , Sustainable Development , Americas , Caribbean Region , Health Services Research , Social Determinants of Health , Sustainable Development , Caribbean Region
20.
PLoS Negl Trop Dis ; 12(11): e0006791, 2018 11.
Article in English | MEDLINE | ID: mdl-30383809

ABSTRACT

Mobile applications (apps) can bring health research and its potential downstream benefits closer to underserved populations. Drawing on experience developing an app for detecting and referring cases of cutaneous leishmaniasis in Colombia, called Guaral/app, we review key steps in creating such mobile health (mHealth) tools. These require consideration of the sociotechnical context using methods such as systems analysis and human-centered design (HCD), predicated on engagement and iteration with all stakeholders. We emphasize usability and technical concerns and describe the interdependency of technical and human considerations for mHealth systems in rural communities.


Subject(s)
Biomedical Research/methods , Cell Phone/statistics & numerical data , Neglected Diseases/diagnosis , Tropical Medicine/methods , Biomedical Research/instrumentation , Humans , Mobile Applications , Neglected Diseases/epidemiology , Software , Tropical Medicine/instrumentation
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