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1.
Front Public Health ; 11: 1159622, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37942246

RESUMEN

Despite of contact restrictions, population mobility remains the main reason for the spread of SARS-CoV-2. The state of Baden-Württemberg (BW), Germany, approved a model study in Tübingen (TÜMOD) to evaluate how mandatory rapid diagnostic tests (RDT) could reduce transmission. Between 16 March and 24 April 2021, approximately 165,000 residents and visitors to the city were screened for SARS CoV-2 infection using Abbott Panbio™ COVID-19 Antigen rapid test device. We assessed incidences and recorded epidemiological characteristics in a subset of 4,118 participants recruited at three of the nine testing stations. PCR tests were performed in RDT-positives to determine the positive predictive value (PPV), and circulating variants of SARS-CoV-2 were identified by whole-genome sequencing. 2,282 RDT-negative samples were tested by pooled PCR to calculate the false negative rate (FNR). Viral load was compared between variants. 116 (3%) participants were positive by RDT, and of these, 57 (49%) were positive by PCR, 55 (47%) were negative. This resulted in a PPV of 51%. Of the 57 positives, 52 SARS-CoV-2 genomes were successfully sequenced. Of these, 50 belonged to the B.1.1.7 lineage, which had a high viral load (average Ct = 19). Of the 2,282 RDT negatives tested, all were PCR negative (FNR 0%). At the end of TÜMOD, the incidence in Tübingen, which was initially lower, had reached the incidence in the state of BW. While it is difficult to assess the impact of TÜMOD on incidence independent of confounding factors, further studies are needed to identify the effect of close-meshed testing on infection rates.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , COVID-19/epidemiología , Reacción en Cadena de la Polimerasa , Alemania/epidemiología
2.
Front Cell Infect Microbiol ; 13: 1159814, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37124042

RESUMEN

Introduction: Mansonella species are filarial parasites that infect humans worldwide. Although these infections are common, knowledge of the pathology and diversity of the causative species is limited. Furthermore, the lack of sequencing data for Mansonella species, shows that their research is neglected. Apart from Mansonella perstans, a potential new species called Mansonella sp "DEUX" has been identified in Gabon, which is prevalent at high frequencies. We aimed to further determine if Mansonella sp "DEUX" is a genotype of M. perstans, or if these are two sympatric species. Methods: We screened individuals in the area of Fougamou, Gabon for Mansonella mono-infections and generated de novo assemblies from the respective samples. For evolutionary analysis, a phylogenetic tree was reconstructed, and the differences and divergence times are presented. In addition, mitogenomes were generated and phylogenies based on 12S rDNA and cox1 were created. Results: We successfully generated whole genomes for M. perstans and Mansonella sp "DEUX". Phylogenetic analysis based on annotated protein sequences, support the hypothesis of two distinct species. The inferred evolutionary analysis suggested, that M. perstans and Mansonella sp "DEUX" separated around 778,000 years ago. Analysis based on mitochondrial marker genes support our hypothesis of two sympatric human Mansonella species. Discussion: The results presented indicate that Mansonella sp "DEUX" is a new Mansonella species. These findings reflect the neglect of this research topic. And the availability of whole genome data will allow further investigations of these species.


Asunto(s)
Mansonella , Simpatría , Animales , Humanos , Mansonella/genética , Filogenia , ADN Ribosómico , Secuencia de Aminoácidos
3.
J Travel Med ; 30(1)2023 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-36547229

RESUMEN

BACKGROUND: Schistosomiasis is a neglected tropical disease caused by trematodes of the genus Schistosoma. Schistosoma haematobium causes urogenital schistosomiasis (UGS), a chronic disease characterized by pathology of the urogenital tract leading to potentially severe morbidity for which the treatment is poorly standardized. We conducted a survey in TropNet centres on the clinical presentations and management strategies of complicated urogenital schistosomiasis (cUGS). METHODS: We reviewed the clinical records of patients seen at TropNet centres over a 20-year timespan (January 2001-December 2020). Case definition for cUGS included the presence of urogenital cancer, obstructive uropathy, kidney insufficiency of all grades and female or male genital involvement leading to infertility. Collected data included demographic information, patient category (traveller or migrant), imaging data, microbiological data (serology results and presence/absence of eggs in urine), histological features and outcome at last visit recorded. RESULTS: Eight centres contributed with at least one case. Overall, 31 patients matched the inclusion criteria. Sub-Saharan Africa was the most likely place of infection for included patients. Median age was 30.6 years (range 21-46, interquartile ranges, IQR 27-33). Most patients (28/31, 90.3%) were males. Hydronephrosis was the most frequent complication, being present in 18 (58.1%) patients, followed by cancer, present in 5 patients (16.1%); 27 patients (87.1%) required surgical management of some sort. Use of praziquantel varied across centres, with six different regimens employed. DISCUSSION: Very few cases of cUGSs were found in our survey, possibly indicating underdiagnosis of this condition. Hydronephrosis was the most frequently observed urogenital complication, and most patients required invasive procedures. Infection by S. haematobium can result in considerable morbidity, resulting in clinically challenging presentations requiring a multidisciplinary approach. As such, development of common protocols for early diagnosis and treatment is urgently needed.


Asunto(s)
Hidronefrosis , Esquistosomiasis Urinaria , Adulto , Animales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Europa (Continente) , Enfermedades Desatendidas , Estudios Retrospectivos , Schistosoma haematobium , Esquistosomiasis Urinaria/tratamiento farmacológico
5.
PLoS Negl Trop Dis ; 16(5): e0010340, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35503786

RESUMEN

BACKGROUND: Annual mass drug administrations (MDA) of ivermectin will strongly reduce Onchocerca volvulus microfilariae (mf) in the skin and in the onchocerciasis patients' eyes. Ivermectin treatment will also affect the expression of immunity in patients, such that activated immune defenses may help control and contribute to clearance of mf of O. volvulus. Longitudinal surveys are a prerequisite to determining the impact of ivermectin on the status of anti-parasite immunity, notably in risk zones where parasite transmission and active O. volvulus infections persist. METHODOLOGY/PRINCIPAL FINDINGS: Onchocerciasis patients were treated annually with ivermectin and their Onchocerca volvulus antigen (OvAg) specific IgG and cellular responses were investigated before and at 30 years post initial ivermectin treatment (30yPT). Repeated annual ivermectin treatments eliminated persisting O. volvulus microfilariae (mf) from the skin of patients and abrogated patent infections. The OvAg-specific IgG1 and IgG4 responses were diminished at 30yPT to the levels observed in endemic controls. Prior to starting ivermectin treatment, OvAg-induced cellular productions of IL-10, IFN-γ, CCL13, CCL17 and CCL18 were low in patients, and at 30yPT, cellular cytokine and chemokine responses increased to the levels observed in endemic controls. In contrast, mitogen(PHA)- induced IL-10, IFN-γ, CCL17 and CCL18 cellular production was diminished. This divergent response profile thus revealed increased parasite antigen-specific but reduced polyclonal cellular responsiveness in patients. The transmission of O. volvulus continued at the patients' location in the Mô river basin in central Togo 2018 and 2019 when 0.58% and 0.45%, respectively, of Simulium damnosum s.l. vector blackflies carried O. volvulus infections. CONCLUSIONS/SIGNIFICANCE: Repeated annual ivermectin treatment of onchocerciasis patients durably inhibited their patent O. volvulus infections despite ongoing low-level parasite transmission in the study area. Repeated MDA with ivermectin affects the expression of immunity in patients. O. volvulus parasite-specific antibody levels diminished to levels seen in infection-free endemic controls. With low antibody levels, antibody-dependent cellular cytotoxic responses against tissue-dwelling O. volvulus larvae will weaken. O. volvulus antigen inducible cytokine and chemokine production increased in treated mf-negative patients, while their innate responsiveness to mitogen declined. Such lower innate responsiveness in elderly patients could contribute to reduced adaptive immune responses to parasite infections and vaccines. On the other hand, increased specific cellular chemokine responses in mf-negative onchocerciasis patients could reflect effector cell activation against tissue invasive larval stages of O. volvulus. The annual Simulium damnosum s.l. biting rate observed in the Mô river basin was similar to levels prior to initiation of MDA with ivermectin, and the positive rtPCR results reported here confirm ongoing O. volvulus transmission.


Asunto(s)
Vólvulo Intestinal , Onchocerca volvulus , Oncocercosis , Parásitos , Simuliidae , Anciano , Animales , Citocinas , Humanos , Inmunoglobulina G , Interleucina-10 , Ivermectina/uso terapéutico , Microfilarias , Mitógenos/uso terapéutico , Onchocerca , Simuliidae/parasitología , Togo/epidemiología
6.
PLoS Negl Trop Dis ; 16(2): e0010099, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35108275

RESUMEN

BACKGROUND: The infestation with Echinococcus multilocularis larvae may persist in humans for up to decades without evident clinical symptoms. Longitudinal investigations are needed to understand the dynamic immunological processes in alveolar echinococcosis (AE) patients associated with an active and progressive, a stable or a regressive course of disease. METHODOLOGY/PRINCIPAL FINDINGS: This study evaluated the E. multilocularis specific antibody responses, systemic cytokine, and chemokine serum levels over a 10-year follow-up period, as well as cellular responsiveness in AE patients. Our results demonstrate a rapid decrease in antibodies against E. multilocularis specific antigen Em2+. Especially in cured patients, these antibodies remained negative, making them a significant predictor for cured AE. E. multilocularis specific IgG4, and indirect hemagglutination IHA decreased later in time, after around 5 years. While total IgE did not show significant dynamics over the course of disease, E. multilocularis specific IgE decreased after one to two years, and increasing levels were a significant predictor of progressive disease. There was no significant change in systemic IL-8, IL-9, CCL18 or CCL20 serum levels over time. Univariate analysis across groups indicated lower IL-8 levels in cured patients; however, this result could not be confirmed by multivariate analysis. Levels of CCL17 decreased during treatment, especially in cured patients, and thus might serve as a predictive or risk factor for progressive disease. Levels of IL-10 and CCL13 decreased during disease, especially after five and ten years of intervention. The E. multilocularis antigen (EmAg) inducible cellular productions of MCP1(CCL13), TARC(CCL17) and PARC(CCL18) were lowest in patients with cured AE and infection-free controls, while the EmAg inducible cellular production of IFN-γ increased after cure. Significant positive cytokine and chemokine correlations were observed in AE patients for IL-9, IL-10, CCL13(MCP-4), CCL17(TARC) and CCL20(LARC)(for all p<0.001). E. multilocularis specific IgG4 response correlated positively with TARC (p<0.001). Both markers enhanced over time in progressive disease and decreased after cure. The levels of IL-8, IL-10, MCP4 and LARC enhanced with AE regression. CONCLUSIONS/SIGNIFICANCE: Repeated biomarker surveys are advisable to evaluate progression or regression of disease during longitudinal follow-up and such analyses can support imaging techniques and improve staging of AE patients.


Asunto(s)
Equinococosis Hepática/parasitología , Equinococosis Hepática/terapia , Echinococcus multilocularis , Animales , Antígenos Helmínticos , Biomarcadores/sangre , Citocinas , Estudios de Seguimiento , Regulación de la Expresión Génica/inmunología , Humanos
7.
Nat Commun ; 12(1): 2518, 2021 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-33947856

RESUMEN

Immunization with Plasmodium falciparum (Pf) sporozoites under chemoprophylaxis (PfSPZ-CVac) is the most efficacious approach to malaria vaccination. Implementation is hampered by a complex chemoprophylaxis regimen and missing evidence for efficacy against heterologous infection. We report the results of a double-blinded, randomized, placebo-controlled trial of a simplified, condensed immunization regimen in malaria-naive volunteers (EudraCT-Nr: 2018-004523-36). Participants are immunized by direct venous inoculation of 1.1 × 105 aseptic, purified, cryopreserved PfSPZ (PfSPZ Challenge) of the PfNF54 strain or normal saline (placebo) on days 1, 6 and 29, with simultaneous oral administration of 10 mg/kg chloroquine base. Primary endpoints are vaccine efficacy tested by controlled human malaria infection (CHMI) using the highly divergent, heterologous strain Pf7G8 and safety. Twelve weeks following immunization, 10/13 participants in the vaccine group are sterilely protected against heterologous CHMI, while (5/5) participants receiving placebo develop parasitemia (risk difference: 77%, p = 0.004, Boschloo's test). Immunization is well tolerated with self-limiting grade 1-2 headaches, pyrexia and fatigue that diminish with each vaccination. Immunization induces 18-fold higher anti-Pf circumsporozoite protein (PfCSP) antibody levels in protected than in unprotected vaccinees (p = 0.028). In addition anti-PfMSP2 antibodies are strongly protection-associated by protein microarray assessment. This PfSPZ-CVac regimen is highly efficacious, simple, safe, well tolerated and highly immunogenic.


Asunto(s)
Vacunas contra la Malaria/inmunología , Malaria Falciparum/prevención & control , Plasmodium falciparum/inmunología , Vacunación/métodos , Vacunas Atenuadas/inmunología , Adulto , Antimaláricos/uso terapéutico , Línea Celular , Quimioprevención , Cloroquina/uso terapéutico , Femenino , Humanos , Inmunoglobulina G/inmunología , Vacunas contra la Malaria/efectos adversos , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/inmunología , Malaria Falciparum/parasitología , Masculino , Parasitemia/inmunología , Análisis por Matrices de Proteínas , Esporozoítos/inmunología , Vacunación/efectos adversos , Vacunas Atenuadas/efectos adversos
8.
Int J Infect Dis ; 106: 265-268, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33848675

RESUMEN

INTRODUCTION: Use of hydroxychloroquine in patients with coronavirus disease 2019 (COVID-19) was widespread and uncontrolled until recently. Patients vulnerable to severe COVID-19 are at risk of hydroxychloroquine interactions with co-morbidities and co-medications contributing to detrimental, including fatal, adverse treatment effects. METHODS: A retrospective survey was undertaken of health conditions and co-medications of patients with COVID-19 who were pre-screened for enrolment in a randomized, double-blind, placebo-controlled hydroxychloroquine multi-centre trial. RESULTS: The survey involved 305 patients [median age 71 (interquartile range 59-81) years]. The majority of patients (n = 279, 92%) considered for inclusion in the clinical trial were not eligible, mainly due to safety concerns caused by health conditions or co-medications. The most common were QT-prolonging drugs (n = 188, 62%) and haematologic/haemato-oncologic diseases (n = 39, 13%) which prohibited the administration of hydroxychloroquine. In addition, 165 (54%) patients had health conditions and 167 (55%) patients were on co-medications that did not prohibit the use of hydroxychloroquine but had a risk of adverse interactions with hydroxychloroquine. The most common were diabetes (n = 86, 28%), renal insufficiency (n = 69, 23%) and heart failure (n = 58, 19%). CONCLUSION: The majority of hospitalized patients with COVID-19 had health conditions or took co-medications precluding safe treatment with hydroxychloroquine. Therefore, hydroxychloroquine should be administered with extreme caution in elderly patients with COVID-19, and only in clinical trials.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Hidroxicloroquina/efectos adversos , SARS-CoV-2 , Anciano , Anciano de 80 o más Años , Comorbilidad , Contraindicaciones de los Medicamentos , Interacciones Farmacológicas , Femenino , Alemania/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
9.
Wien Klin Wochenschr ; 133(9-10): 500-508, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33398458

RESUMEN

Medical research in sub-Saharan Africa is of high priority for societies to respond adequately to local health needs. Often enough it remains a challenge to build up capacity in infrastructure and human resources to highest international standards and to sustain this over mid-term to long-term periods due to difficulties in obtaining long-term institutional core funding, attracting highly qualified scientists for medical research and coping with ever changing structural and political environments. The Centre de Recherches Médicales de Lambaréné (CERMEL) serves as model for how to overcome such challenges and to continuously increase its impact on medical care in Central Africa and beyond. Starting off as a research annex to the Albert Schweitzer Hospital in Lambaréné, Gabon, it has since then expanded its activities to academic and regulatory clinical trials for drugs, vaccines and diagnostics in the field of malaria, tuberculosis, and a wide range of poverty related and neglected tropical infectious diseases. Advancing bioethics in medical research in Africa and steadily improving its global networks and infrastructures, CERMEL serves as a reference centre for several international consortia. In close collaboration with national authorities, CERMEL has become one of the main training hubs for medical research in Central Africa. It is hoped that CERMEL and its leitmotiv "to improve medical care for local populations" will serve as an inspiration to other institutions in sub-Saharan Africa to further increase African capacity to advance medicine.


Asunto(s)
Investigación Biomédica , Enfermedades Transmisibles , Tuberculosis , Gabón , Humanos , Pobreza
10.
Trop Med Int Health ; 25(3): 380-386, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31808594

RESUMEN

OBJECTIVE: Ivermectin is safe and widely used for treating helminth infections. It also kills arthropods feeding on treated subjects, including malaria vectors. Thus, ivermectin mass drug administration as an additional tool for malaria control is being evaluated by WHO. As in vitro data, animal experiments and epidemiological observations suggest that ivermectin has a direct effect on the liver stages of the malaria parasite, this study was designed to assess the prophylactic effect of ivermectin on Plasmodium falciparum controlled human malaria infection. METHODS: A total of 4 volunteers were randomised to placebo, and 8 volunteers were randomised to receive ivermectin 0.4 mg/kg, orally, once 2 h before being experimentally infected intravenously with 3200 P. falciparum sporozoites. The primary endpoint was time to parasitaemia detected by positive thick blood smear; RT-qPCR was performed in parallel. RESULTS: All but one volunteer became thick blood smear positive between day 11 and day 12 after infection, and there was no significant effect of ivermectin on parasitaemia. CONCLUSION: Ivermectin - at the dose used - has no clinically relevant activity against the pre-erythrocytic stages of P. falciparum.


OBJECTIF: L'ivermectine est sûr et largement utilisé pour traiter les helminthiases. Il tue également les arthropodes se nourrissant sur les sujets traités, y compris les vecteurs du paludisme. Ainsi, l'administration en masse d'ivermectine en tant qu'outil supplémentaire de lutte contre le paludisme est actuellement évaluée par l'OMS. Comme les données in vitro, les expériences sur animaux et les observations épidémiologiques suggèrent que l'ivermectine a un effet direct sur les stades hépatiques du parasite du paludisme, cette étude a été conçue pour évaluer l'effet prophylactique de l'ivermectine sur l'infection paludéenne humaine par Plasmodium falciparum contrôlée. MÉTHODES: Quatre volontaires ont été randomisés pour un placebo et 8 volontaires ont été randomisés pour recevoir de l'ivermectine à 0,4 mg/kg en une fois par voie orale, 2 heures avant d'être expérimentalement infectés par voie intraveineuse avec 3.200 sporozoïtes de P. falciparum. Le critère d'évaluation principal était le temps à la parasitémie détectée par un frottis sanguin épais positif. Une RT-qPCR a été réalisée en parallèle. RÉSULTATS: Tous les volontaires sauf un sont devenus positifs pour les frottis sanguins épais entre le jour 11 et le jour 12 après l'infection et il n'y avait aucun effet significatif de l'ivermectine sur la parasitémie. CONCLUSION: L'ivermectine - à la dose utilisée - n'a aucune activité cliniquement pertinente contre les stades pré-érythrocytaires de P. falciparum.


Asunto(s)
Antimaláricos/uso terapéutico , Ivermectina/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Plasmodium falciparum/efectos de los fármacos , Adulto , Antimaláricos/farmacología , Femenino , Humanos , Ivermectina/farmacología , Malaria Falciparum/parasitología , Masculino , Administración Masiva de Medicamentos , Resultado del Tratamiento , Adulto Joven
11.
Artículo en Alemán | MEDLINE | ID: mdl-31828371

RESUMEN

Globally, 3.1 billion people live in areas endemic for malaria (the tropics and subtropics). Annually, around 200 million fall ill, and around 500,000 persons die as a result of this infection. Mainly children are the victims. In order to control and eventually prevent any new infection, the development of effective vaccines is pivotal. In this review, background information about the history of vaccine development and malaria disease as well as possibilities for therapy and control is given. In the main part of the article, an update on the development of vaccines against Plasmodium falciparum is provided followed by an extensive discussion.Malaria is a parasitic infectious disease caused by the single cell organism Plasmodium. Five different Plasmodium species can induce disease in humans with P. falciparum being the origin for more than 99% of infections in Africa. The vector is the Anopheles mosquito. The life cycle of Plasmodium offers several approaches for vaccines to have an impact. Out of around 70 candidates, pre-erythrocytic vaccine candidates interfering with the liver phase of the parasite are the most developed. However, a vaccine with more than 75% efficacy, as required by the World Health Organization (WHO), is not yet in sight.Currently, for the first time, a moderately efficacious vaccine (RTS,S/AS01) is being applied in large-scale operations. But it is obvious that malaria can only be controlled in combination with concurring measures. For example, the use of impregnated mosquito nets, indoor residual spraying, elimination of vector breeding sites, rapid diagnosis, and therapy of the infection as well as a functioning health system are important elements, which can hardly be guaranteed in areas characterized by poverty.


Asunto(s)
Vacunas contra la Malaria , Malaria Falciparum , Malaria , Animales , Niño , Alemania , Humanos , Plasmodium falciparum
12.
Parasite Epidemiol Control ; 3(2): 77-87, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29774301

RESUMEN

BACKGROUND: Mansonella perstans, Onchocerca volvulus and Strongyloides stercoralis are widespread helminth parasites in the tropics. Their distribution remains difficult to determine as it may change during national disease control programs and with regional mass drug administration (MDA). Epidemiological surveys are of importance to evaluate the geographical distribution of these helminth parasites and the diseases they may cause, however, up to date epidemiological evaluations on M. perstans and S. stercoralis in Togo are rare, and surveys on O. volvulus are important especially under the aspect of MDA of ivermectin which is performed since decades. METHODS: Dry blood samples (n = 924) were collected from rural populations in the Régions Central and Plateaux in Togo, and analyzed by parasite-specific real-time PCR and ELISA techniques. RESULTS: Dry blood samples from 733 persons where investigated by real-time PCR tested for DNA of blood-circulating M. perstans microfilaria, and a prevalence of 14.9% was detected. Distinct differences were observed between genders, positivity was higher in men increasing with age, and prevalence was highest in the Région Plateaux in Togo. IgG4 responses to O. volvulus antigen (OvAg) were studied in 924 persons and 59% were found positive. The distribution of parasite infestation between age and gender groups was higher in men increasing with age, and regional differences were detected being highest in the Région Plateaux. The diagnostic approach disclosed 64,5% positive IgG4 responses to S. stercoralis infective third-stage larvae-specific antigen (SsL3Ag) in the surveyed regions. Antigen cross reactivity of SsL3Ag with parasite co-infections may limit the calculated prevalence. Singly IgG4 positive for SsL3Ag were 13.9%, doubly positive for OvAg and SsL3Ag were 35.5% and triply positive for M. perstans, O. volvulus and S. stercoralis were 9.9%. CONCLUSIONS: Mansonelliasis, onchocerciasis and strongyloidiasis remain prevalent in the surveyed regions, yet with local differences. Our observations suggest that transmission of M. perstans, O. volvulus and S. stercoralis may be ongoing. The degree of positive test results in the examined rural communities advocate for the continuation of MDA with ivermectin and albendazole, and further investigations should address the intensity of transmission of these parasites.

14.
Oncotarget ; 9(10): 9073-9087, 2018 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-29507675

RESUMEN

Cytostatic drugs used in cancer therapy were evaluated for their capacity to inhibit Echinococcus multilocularis metacestode growth and proliferation. Metacestode tissues were exposed in vitro to docetaxel, doxorubicin, navelbine, paclitaxel, and vorinostat for 1 week, then incubated in drug-free culture, and thereafter metacestodes were injected into the peritoneum of Meriones unguiculatus. Magnetic resonance imaging (MRI) and simultaneous positron emission tomography (PET) were applied to monitor in vivo growth of drug-exposed E. multilocularis in Meriones. At 3 month p.i., docetaxel (at 10 µM, 5 µM and 2 µM) inhibited in vivo growth and proliferation of E. multilocularis, and at 5 months p.i., only in the 2 µM docetaxel exposure group 0.3 cm 3 of parasite tissue was found. With paclitaxel and navelbine the in vivo growth of metacestodes was suppressed until 3 months p.i., thereafter, parasite tissues enlarged up to 3 cm 3 in both groups. E. multilocularis tissues of more than 10 g developed in Meriones injected with metacestodes which were previously exposed in vitro to doxorubicin, navelbine, paclitaxel or vorinostat. In Meriones infected with metacestodes previously exposed to docetaxel, the in vivo grown parasite tissues weighted 0.2 g. In vitro cultured E. multilocularis metacestodes exposed to docetaxel did not produce vesicles until 7 weeks post drug exposure, while metacestodes exposed to doxorubicin, navelbine and vorinostat proliferated continuously. In summary, docetaxel, and less efficaciously paclitaxel, inhibited in vivo and in vitro parasite growth and proliferation, and these observations suggest further experimental studies with selected drug combinations which may translate into new treatment options against alveolar echinococcosis.

15.
PLoS Negl Trop Dis ; 12(3): e0006312, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29494606

RESUMEN

BACKGROUND: Mass drug administration (MDA) of ivermectin has become the main intervention to control onchocerciasis or "river blindness". In Togo, after many years of MDA, Onchocerca volvulus infection has declined dramatically, and elimination appears achievable, but in certain river basins the current situation remains unknown. We have conducted parasitological, serological, ophthalmological, and entomological assessments in northern and central Togo within the river basins of Ôti, Kéran and Mô. METHODOLOGY/PRINCIPAL FINDINGS: Examinations were completed in 1,455 participants from 11 onchocerciasis sentinel villages, and O. volvulus transmission by Simulium damnosum sensu lato (s.l.) was evaluated. In children (aged 1-10 years), the prevalence of microfilariae (Mf) was 2.3% and in adults it ranged from 5.1 to 13.3%. Positive IgG4 responses to O. volvulus adult (crude) worm antigen (OvAg) and the recombinant Ov16 antigen were in all-ages 48.7% and 34.4%, and 29.1% and 14.9% in children, respectively. In the river basin villages of Kéran, Mô and Ôti, the IgG4 seroprevalences to OvAg in children were 51.7%, 23.5% and 12.7%, respectively, and to the Ov16 antigen 33.3% (Kéran) and 5.2% (Ôti). Onchocerciasis ocular lesions (punctate keratitis, evolving iridocyclitis and chorioretinitis) were observed in children and young adults. O. volvulus-specific DNA (Ov150) was detected by poolscreen in vector samples collected from Tchitchira/Kéran(22.8%), Bouzalo/Mô(11.3%), Baghan/Mô(2.9%) and Pancerys/Ôti(4.9%); prevalences of O. volvulus infection in S. damnosum s.l. were, respectively, 1%, 0.5%, 0.1% and 0.2%. CONCLUSIONS/SIGNIFICANCE: In the northern and central river basins in Togo, interruption of O. volvulus transmission has not yet been attained. Patent O. volvulus infections, positive antibody responses, progressive ocular onchocerciasis were diagnosed, and parasite transmission by S. damnosum s.l. occurred close to the survey locations. Future interventions may require approaches selectively targeted to non-complying endemic populations, to the seasonality of parasite transmission and national onchocerciasis control programs should harmonize cross-border MDA as a coordinated intervention.


Asunto(s)
Ivermectina/uso terapéutico , Oncocercosis Ocular/epidemiología , Oncocercosis Ocular/prevención & control , Oncocercosis Ocular/transmisión , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Animales , Anticuerpos Antihelmínticos/sangre , Niño , Preescolar , ADN de Helmintos/sangre , Femenino , Humanos , Insectos Vectores/parasitología , Masculino , Administración Masiva de Medicamentos/métodos , Microfilarias , Persona de Mediana Edad , Onchocerca volvulus , Estudios Seroepidemiológicos , Simuliidae/parasitología , Togo/epidemiología , Adulto Joven
16.
Lancet ; 390(10097): 898-912, 2017 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-28684024

RESUMEN

Germany has become a visible actor in global health in the past 10 years. In this Series paper, we describe how this development complements a broad change in perspective in German foreign policy. Catalysts for this shift have been strong governmental leadership, opportunities through G7 and G20 presidencies, and Germany's involvement in managing the Ebola virus disease outbreak. German global health engagement has four main characteristics that are congruent with the health agenda of the Sustainable Development Goals; it is rooted in human rights, multilateralism, the Bismarck model of social protection, and a link between development and investment on the basis of its own development trajectory after World War 2. The combination of momentum and specific characteristics makes Germany well equipped to become a leader in global health, yet the country needs to accept additional financial responsibility for global health, expand its domestic global health competencies, reduce fragmentation of global health policy making, and solve major incoherencies in its policies both nationally and internationally.


Asunto(s)
Salud Global/tendencias , Política de Salud , Liderazgo , Política , Política Pública/tendencias , Alemania , Gobierno , Humanos , Cooperación Internacional
17.
Int J Infect Dis ; 56: 81-84, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27888000

RESUMEN

Both routine and research tuberculosis (TB) laboratory capacity urgently need to be expanded in large parts of Sub-Saharan Africa. In 2009, the Centre de Recherches Médicales de Lambaréné (CERMEL) took a strategic decision to expand its activities by building TB laboratory capacity to address research questions and to improve routine diagnostic and treatment capacity. Over the past 7 years, a standard laboratory has been developed that is contributing significantly to TB diagnosis, treatment, and control in Gabon; training has also been provided for TB research staff in Central Africa. CERMEL has a cordial relationship with the Gabon National TB Control Programme (PNLT), which has culminated in a successful Global Fund joint application. This endeavour is considered a model for similar developments needed in areas of high TB prevalence and where TB control remains poor to date.


Asunto(s)
Creación de Capacidad , Laboratorios/organización & administración , Laboratorios/provisión & distribución , Salud Pública , Tuberculosis/prevención & control , Tuberculosis/terapia , África del Sur del Sahara/epidemiología , Antituberculosos/uso terapéutico , Recursos en Salud , Humanos , Ciencia del Laboratorio Clínico/educación , Ciencia del Laboratorio Clínico/organización & administración , Vigilancia de la Población , Prevalencia , Tuberculosis/epidemiología
18.
New Microbiol ; 39(4): 287-289, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28004846

RESUMEN

Zika virus (ZIKV) is mainly transmitted by mosquitoes bites. However, transmission by sexual contacts has been reported in 11 non endemic countries. The rapid spread of ZIKV in Latin American and Caribbean Countries (LCR), person-to-person transmission and perceived risk on people's well being can affect the emerging economies of LCR which historically dependent on truism. Here we present an analysis on economic outputs for assessing the current impact of ZIKV on markets. Our analysis show an unexpected resilience of LCR markets to international alerts. This positive response represents an opportunity to scale-up interventions for preventing the further spreading of the ZIKV epidemic.


Asunto(s)
Brotes de Enfermedades/economía , Infección por el Virus Zika/economía , Infección por el Virus Zika/epidemiología , Virus Zika , Humanos , América Latina/epidemiología , México , Factores de Tiempo , Indias Occidentales/epidemiología
19.
Mol Immunol ; 73: 98-111, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27062712

RESUMEN

Prenatal exposure to parasite antigens or allergens will influence the profile and strength of postnatal immune responses, such contact may tolerize and increase susceptibility to future infections or sensitize to environmental allergens. Exposure in utero to parasite antigens will distinctly alter cellular gene expression in newborns. Gene microarrays were applied to study gene expression in umbilical cord blood cell (UCBC) from parasite-exposed (Para-POS) and non-exposed (Para-NEG) neonates. UCBC were activated with antigens of helminth (Onchocerca volvulus), amoeba (Entamoeba histolytica) or allergens of mite (Dermatophagoides farinae). When UCBC from Para-POS and Para-NEG newborns were exposed to helminth antigens or allergens consistent differences occurred in the expression of genes encoding for MHC class I and II alleles, signal transducers of activation and transcription (STATs), cytokines, chemokines, immunoglobulin heavy and light chains, and molecules associated with immune regulation (SOCS, TLR, TGF), inflammation (TNF, CCR) and apoptosis (CASP). Expression of genes associated with innate immune responses were enhanced in Para-NEG, while in Para-POS, the expression of MHC class II and STAT genes was reduced. Within functional gene networks for cellular growth, proliferation and immune responses, Para-NEG neonates presented with significantly higher expression values than Para-POS. In Para-NEG newborns, the gene cluster and pathway analyses suggested that gene expression profiles may predispose for the development of immunological, hematological and dermatological disorders upon postnatal helminth parasite infection or allergen exposure. Thus, prenatal parasite contact will sensitize without generating aberrant inflammatory immune responses, and increased pro-inflammatory but decreased regulatory gene expression profiles will be present in those neonates lacking prenatal parasite antigen encounter.


Asunto(s)
Amebiasis/complicaciones , Helmintiasis/complicaciones , Complicaciones Parasitarias del Embarazo/inmunología , Efectos Tardíos de la Exposición Prenatal/inmunología , Amebiasis/genética , Amebiasis/inmunología , Animales , Antígenos Dermatofagoides/inmunología , Antígenos Helmínticos/inmunología , Antígenos de Protozoos/inmunología , Femenino , Sangre Fetal , Helmintiasis/genética , Helmintiasis/inmunología , Humanos , Recién Nacido , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena de la Polimerasa , Embarazo , Complicaciones Parasitarias del Embarazo/genética , Efectos Tardíos de la Exposición Prenatal/genética , Transcriptoma/inmunología
20.
Cell Cycle ; 15(7): 974-85, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26919204

RESUMEN

Cdc45 is an essential protein that together with Mcm2-7 and GINS forms the eukaryotic replicative helicase CMG. Cdc45 seems to be rate limiting for the initial unwinding or firing of replication origins. In line with this view, Cdc45-overexpressing cells fired at least twice as many origins as control cells. However, these cells displayed an about 2-fold diminished fork elongation rate, a pronounced asymmetry of replication fork extension, and an early S phase arrest. This was accompanied by H2AX-phosphorylation and subsequent apoptosis. Unexpectedly, we did not observe increased ATR/Chk1 signaling but rather a mild ATM/Chk2 response. In addition, we detected accumulation of long stretches of single-stranded DNA, a hallmark of replication catastrophe. We conclude that increased origin firing by upregulated Cdc45 caused exhaustion of the single-strand binding protein RPA, which in consequence diminished the ATR/Chk1 response; the subsequently occurring fork breaks led to an ATM/Chk2 mediated phosphorylation of H2AX and eventually to apoptosis.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Replicación del ADN , Apoptosis , ADN de Cadena Simple/análisis , Células HeLa , Histonas/metabolismo , Humanos , Origen de Réplica , Puntos de Control de la Fase S del Ciclo Celular , Transducción de Señal
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