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1.
Pathogens ; 10(6)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201231

RESUMO

This work was conducted as a cross sectional study to define the disease burden of schistosomiasis in pregnant Madagascan women and to evaluate serological and molecular diagnostic assays. A total of 1154 residual EDTA blood samples from pregnant Madagascan women were assessed. The nucleic acid extractions were subjected to in-house real-time PCRs specifically targeting S. mansoni complex, S. haematobium complex, and African Schistosoma spp. on genus level, while the EDTA plasma samples were analyzed using Schistosoma-specific IgG and IgM commercial ELISA and immunofluorescence assays. The analyses indicated an overall prevalence of schistosomiasis in Madagascan pregnant women of 40.4%, with only minor regional differences and differences between serology- and blood PCR-based surveillance. The S. mansoni specific real-time PCR showed superior sensitivity of 74% (specificity 80%) compared with the genus-specific real-time PCR (sensitivity 13%, specificity 100%) in blood. The laborious immunofluorescence (sensitivity IgM 49%, IgG 87%, specificity IgM 85%, IgG 96%) scored only slightly better than the automatable ELISA (sensitivity IgM 38%, IgG 88%, specificity IgM 78%, IgG 91%). Infections with S. mansoni were detected only. The high prevalence of schistosomiasis recorded here among pregnant women in Madagascar calls for actions in order to reduce the disease burden.

3.
Pathogens ; 10(2)2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33572338

RESUMO

This study aimed to assess standard and harsher nucleic acid extraction schemes for diagnostic helminth real-time PCR approaches from stool samples. A standard procedure for nucleic acid extraction from stool and a procedure including bead-beating as well as proteinase K digestion were compared with group-, genus-, and species-specific real-time PCR assays targeting helminths and nonhelminth pathogens in human stool samples. From 25 different in-house and commercial helminth real-time PCR assays applied to 77 stool samples comprising 67 historic samples and 10 external quality assessment scheme samples positively tested for helminths, higher numbers of positive test results were observed after bead-beating-based nucleic acid extraction for 5/25 (20%) real-time PCR assays irrespective of specificity issues. Lower cycle threshold values were observed for one real-time PCR assay after the standard extraction scheme, and for four assays after the bead-beating-based scheme. Agreement between real-time PCR results after both nucleic acid extraction strategies according to Cohen's kappa ranged from poor to almost perfect for the different assays. Varying agreement was observed in eight nonhelminth real-time PCR assays applied to 67 historic stool samples. The study indicates highly variable effects of harsh nucleic acid extraction approaches depending on the real-time PCR assay used.

4.
Mol Ther Methods Clin Dev ; 11: 131-142, 2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30547047

RESUMO

Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease characterized by high levels of pathogenic autoantibodies and tissue damage. Multiple studies showed that dendritic cell (DC) activation plays a critical role in SLE pathogenesis. Human alpha 1 antitrypsin (hAAT) is a serine proteinase inhibitor with potent anti-inflammatory and cytoprotective properties. In this study, we first examined the effects of hAAT on the functions of DCs from lupus-prone mice, and we showed that hAAT treatment efficiently inhibited CpG- (TLR9 agonist) induced activation of bone marrow-derived conventional and plasmacytoid DCs as well as the production of pro-inflammatory cytokines. The hAAT treatment also attenuated DC help for B cell proliferation and immunoglobulin M (IgM) production. We next tested the protective effect of hAAT protein and gene therapy using recombinant adeno-associated virus 8 (rAAV8-CB-hAAT) in a spontaneous lupus mouse model, and we showed that both treatments decreased autoantibody levels. Importantly, rAAV8-CB-hAAT did not induce an immune response to its transgene product (hAAT), but it showed more pronounced therapeutic effects in reducing urine protein levels and extending the lifespan of these mice. These results indicate that AAT has therapeutic potential in the treatment of SLE in humans.

5.
Front Immunol ; 9: 811, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29760693

RESUMO

In untreated HIV infection, the efficacy of T cell responses decreases over the disease course, resulting in disease progression. The reasons for this development are not completely understood. However, immunosuppressive cells are supposedly crucially involved. Treatment strategies to avoid the induction of these cells preserve immune functions and are therefore the object of intense research efforts. In this study, we assessed the effect of treatment intensification [=5-drug antiretroviral therapy (ART)] on the development of suppressive cell subsets. The New Era (NE) study recruited patients with primary HIV infection (PHI) or chronically HIV-infected patients with conventional ART (CHI) and applied an intensified 5-drug regimen containing maraviroc and raltegravir for several years. We compared the frequencies of the immune suppressive cells, namely, the myeloid-derived suppressor cells (MDSCs), regulatory B cells (Bregs), and regulatory T cells (Tregs), of the treatment intensification patients to the control groups, especially to the patients with conventional 3-drug ART, and analyzed the Gag/Nef-specific CD8 T cell responses. There were no differences between PHI and CHI in the NE population (p > 0.11) for any of the studied cell types. Polymorphonuclear myeloid-derived suppressor cell (PMN-MDSC), monocytic myeloid-derived suppressor cell (M-MDSC), and the Breg frequencies were comparable to those of patients with a 3-drug ART. However, the Treg levels were significantly lower in the NE patients than those in 3ART-treated individuals and other control groups (p ≤ 0.0033). The Gag/Nef-specific CD8 T cell response was broader (p = 0.0134) with a higher magnitude (p = 0.026) in the NE population than that in the patients with conventional ART. However, we did not find a correlation between the frequency of the immune suppressive cells and the interferon-gamma+ CD8 T cell response. In the treatment intensification subjects, the frequencies of the immune suppressive cells were comparable or lower than those of the conventional ART-treated subjects, with surprisingly broad HIV-specific CD8 T cell responses, suggesting a preservation of immune function with the applied treatment regimen. Interestingly, these effects were seen in both treatment intensification subpopulations and were not attributed to the start of treatment in primary infection.


Assuntos
Antirretrovirais/uso terapêutico , Linfócitos T CD4-Positivos/citologia , Infecções por HIV/tratamento farmacológico , Linfócitos T Reguladores/citologia , Adulto , Idoso , Linfócitos B Reguladores/citologia , Linfócitos T CD8-Positivos/citologia , Progressão da Doença , Feminino , HIV-1/efeitos dos fármacos , HIV-1/imunologia , Humanos , Interferon gama/imunologia , Leucócitos Mononucleares/citologia , Masculino , Maraviroc/uso terapêutico , Pessoa de Meia-Idade , Células Supressoras Mieloides/citologia , Raltegravir Potássico/uso terapêutico , Carga Viral , Adulto Jovem
6.
Sci Adv ; 2(12): e1601282, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28028536

RESUMO

Humans use a variety of deliberate means to modify biologically rich environs in pursuit of resource stability and predictability. Empirical evidence suggests that ancient hunter-gatherer populations engineered ecological niches to enhance the productivity and availability of economically significant resources. An archaeological excavation of a 3800-year-old wetland garden in British Columbia, Canada, provides the first direct evidence of an engineered feature designed to facilitate wild plant food production among mid-to-late Holocene era complex fisher-hunter-gatherers of the Northwest Coast. This finding provides an example of environmental, economic, and sociopolitical coevolutionary relationships that are triggered when humans manipulate niche environs.


Assuntos
Arqueologia , Jardinagem/história , História Antiga , Alimentos , Humanos , Noroeste dos Estados Unidos
7.
Eur Surg Res ; 54(3-4): 114-26, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25472712

RESUMO

Organ transplantation is still affected by a notable degree of preservation-associated ischemia and reperfusion injury, which can seriously hamper early graft function. The increasing extension of the criteria for donor organ acceptance, especially for organs that have suffered from periods of warm ischemic injury prior to graft retrieval, results in even higher demands on preserving these ischemia-sensitive grafts. Growing attention is thus directed towards more dynamic preservation methods instead of simple static storage. Particularly in grafts that are retrieved after cardiac standstill of the donor, provision of oxygen to enable some kind of regenerative metabolism appears to be desirable, although the optimal temperature for oxygenated preservation/revitalization is still under debate. Hybrid solutions, comprising conventional cold storage for ease of graft procurement and transportation together with more sophisticated 'in-house' reconditioning protocols after arrival at the implantation clinic, might help to minimize graft injury during the critical transition from preservation to reperfusion.


Assuntos
Preservação de Órgãos/tendências , Aerobiose , Animais , Temperatura Baixa , Humanos , Perfusão , Fluxo Pulsátil , Transplante
8.
J Virol ; 82(7): 3791-5, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18199638

RESUMO

Acquired forms of prion diseases or transmissible spongiform encephalopathies are believed to occur following peripheral exposure. Prions initially accumulate in the lymphoid system before spreading to the nervous system, but the underlying mechanisms for prion transfer between the two systems are still elusive. Here we show that ablation of the B-cell-specific transmembrane protein CD19, a coreceptor of the complement system, results in an acceleration of prion neuroinvasion. This appears to be due to an alteration of the follicular dendritic cell (FDC) network within the lymphoid tissue, thereby reducing the distance between FDCs and adjacent nerve fibers that mediate prion neuroinvasion.


Assuntos
Antígenos CD19/imunologia , Linfócitos B/imunologia , Doenças do Sistema Nervoso/imunologia , Scrapie/imunologia , Animais , Células Dendríticas/imunologia , Tecido Linfoide/citologia , Camundongos , Camundongos Knockout , Proteínas PrPSc/análise , Proteínas PrPSc/isolamento & purificação , Baço/química , Análise de Sobrevida
9.
Anticancer Drugs ; 14(1): 79-85, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12544262

RESUMO

The combination of irinotecan (CPT-11), bolus 5-fluorouracil (5-FU) and folinic acid (FA) (Saltz regimen) has recently been questioned as first-line chemotherapy for metastatic colorectal cancer after high early death rates due to gastrointestinal and thromboembolic events were reported in two US trials. Therefore, we carefully evaluated the safety and efficacy of this regimen, with high value placed on the management of delayed diarrhea. Forty-six patients with metastatic colorectal cancer received this first-line treatment in nine German outpatient clinics. Dose reductions were mandatory from the first cycle in case of toxicity grade >2. Chemotherapy was administered only to diarrhea-free patients. During a total of 175 cycles administered treatments were delayed for 1 week in 11.6% and given at a reduced dose in 14.5%. All and 40 patients were evaluable for toxicity and response, respectively. Grade 3/4 toxicities included diarrhea (n=10), leukopenia (n=9), neutropenia (n=3) and anemia (n=4). One non-fatal pulmonary embolism occurred. Four complete responses (CR) and 10 partial responses were seen, for an overall response rate of 35%. In addition, 16 patients (40%) had stable disease. Resectability of liver metastases was achieved in three patients, including one pathologically confirmed CR. Median progression-free and overall survival were 5 and 13 months, respectively. We conclude that outpatient treatment with the Saltz regimen was well tolerated. Severe gastrointestinal toxicity and thromboembolic events were rarely observed and never fatal. As down-staging was possible, combinations of CPT-11 and FA/5-FU should be further investigated in neoadjuvant protocols.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Camptotecina/análogos & derivados , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Adulto , Idoso , Assistência Ambulatorial/estatística & dados numéricos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Irinotecano , Leucovorina/administração & dosagem , Leucovorina/efeitos adversos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taxa de Sobrevida/tendências
10.
Syst Appl Microbiol ; 25(2): 267-74, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12353882

RESUMO

Methanotrophic bacteria play a crucial role in regulating the emission of CH4 from rice fields into the atmosphere. We investigated the CH4 oxidation activity together with the diversity of methanotrophic bacteria in ten rice field soils from different geographic locations. Upon incubation of aerated soil slurries under 7% CH4, rates of CH4 oxidation increased after a lag phase of 1-4 days and reached values of 3-10 micromol d(-1) g-dw(-1) soil. The methanotrophic community was assayed by retrieval of the pmoA gene which encodes the a subunit of the particulate methane monooxygenase. After extraction of DNA from actively CH4-oxidizing soil samples and PCR-amplification of the pmoA, the community was analyzed by Denaturant Gradient Gel Electrophoresis (DGGE) and Terminal Restriction Fragment Length Polymorphism (T-RFLP). DGGE bands were excised, the pmoA re-amplified, sequenced and the encoded amino acid sequence comparatively analyzed by phylogenetic treeing. The analyses allowed the detection of pmoA sequences related to the following methanotrophic genera: the type-I methanotrophs Methylobacter, Methylomicrobium, Methylococcus and Methylocaldum, and the type-II methanotrophs Methylocystis and Methylosinus. T-RFLP analysis detected a similar diversity, but type-II pmoA more frequently than DGGE. All soils but one contained type-II in addition to type-I methanotrophs. Type-I Methylomonas was not detected at all. Different combinations of methanotrophic genera were detected in the different soils. However, there was no obvious geographic pattern of the distribution of methanotrophs.


Assuntos
Bactérias/enzimologia , Variação Genética , Oryza , Oxigenases/genética , Microbiologia do Solo , Agricultura , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Sequência de Bases , China , DNA Bacteriano/análise , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Eletroforese em Gel de Ágar/métodos , Genes Bacterianos , Metano/metabolismo , Dados de Sequência Molecular , Oxigenases/análise , Filipinas , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA , Solo/análise
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