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1.
Zhongguo Zhong Yao Za Zhi ; 44(16): 3569-3575, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602924

RESUMO

To further investigate the metabolism of Tripterygium wilfordii and Paeonia lactiflora micro-emulsion gel in vivo,an LCMS/MS method was established for the determination of triptolide and paeoniflorin in T. wilfordii and P. lactiflora micro-emulsion gel.The extracorporeal recovery rate of blood probe was measured by concentration difference methods( incremental method and decremental method). Meanwhile,the skin and blood micro-dialysis methods of tripterine and paeoniflorin were established,and the pharmacokinetics of T. wilfordii microemulsion gel in skin and blood was studied by micro-dialysis combined with LC-MS/MS quantitative analysis. The results showed that the established method for the determination of triptolide and paeoniflorin in T. wilfordii microemulsion gel was well linear within the required range,and the specificity,recovery rate and degree of precision of the chromatography all conformed to the research requirements of micro-dialysis samples. The stability of freeze-thawing and the residual effect all conformed to the criteria of biological sample methodology. The probe recovery rates measured by incremental method and decremental method were almost consistent with the extracorporeal recovery rate test. The recovery rates of paeoniflorin in skin and blood micro-dialysis were( 30. 60±1. 09) % and( 28. 01± 1. 75) %,respectively. And the recovery rates of skin and blood micro-dialysis were( 26. 79 ± 2. 78) % and( 25. 39±1. 86) %,respectively. The intraday recovery rate of probes was stable within 11 h. The results of pharmacokinetic study showed that the Cmaxvalues of triptolide in skin and blood were( 148. 03±41. 51) and( 76. 77±15. 27) µg·L-1,respectively. And the Tmaxvalues were( 2. 33±0. 29) and( 3. 00± 0) h,respectively. The AUC0-11 hvalues were( 2 814. 05± 1 070. 37) and( 1 580. 63±208. 27) µg·h·L-1,respectively. The MRT0-11 hvalues were( 4. 20± 0. 33) and( 4. 54± 0. 34) h,respectively. The T1/2 values were( 4. 61±4. 11) and( 1. 07± 0. 13) h,respectively. The Cmaxvalues of paeoniflorin in skin and blood were( 991. 88 ± 152. 22) and( 407. 02±120. 06) µg·L-1,respectively. The Tmaxvalues were( 2. 00±0) h and( 2. 83±0. 29) h,respectively. The AUC0-11 hvalues were( 18 430. 27±3 289. 35) and( 6 338. 59 ± 1 659. 32) µg·h·L-1,respectively. The MRT0-11 hvalues were( 4. 29 ± 0. 16) and( 4. 00±0. 05) h,respectively. The T1/2 values were( 2. 16±0. 43) and( 1. 78±0. 48) h,respectively. The results suggested that micro-emulsion gel played a role in forming skin reservoir through percutaneous penetration. It not only could improve drug transdermal efficiency,but also control the sustained release of drug and form a long-term effect.


Assuntos
Sangue/metabolismo , Medicamentos de Ervas Chinesas/farmacocinética , Paeonia/química , Pele/metabolismo , Tripterygium/química , Cromatografia Líquida , Emulsões , Géis , Humanos , Espectrometria de Massas em Tandem
2.
Niger Postgrad Med J ; 26(4): 216-222, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31621661

RESUMO

Background: Neonatal sepsis-related mortalities are the outcome of a complex interaction of maternal-foetal colonisation, transplacental immunity and physical and cellular defence mechanisms of neonates. Objective: The objective of this study was to evaluate the risk factors of mortality in outborn neonatal sepsis. Materials and Methods: A 1-year prospective observational study was undertaken at a tertiary care centre. All referred neonates with maternal and neonatal risk factors of sepsis were enrolled. Blood culture, sepsis screen and other relevant investigations were performed. Results: The mortality rate of neonatal sepsis among outborns was 38.24%. The common presentations of these neonates were respiratory distress, lethargy and hypothermia. On univariate analysis, significant risk factors for mortality included male sex (P = 0.05), weight on admission <1500 g (P < 0.001), hypothermia (P = 0.003), respiratory distress (P = 0.04), cyanosis (P = 0.001), convulsions (P = 0.02), prolonged capillary refill time (P < 0.001), thrombocytopenia (P < 0.001), abnormal radiological finding (P = 0.01), cerebrospinal fluid cellularity (P = 0.002) and positive C-reactive protein (P < 0.001). Maternal factors such as hypertension in pregnancy (P = 0.001) and antepartum haemorrhage (P = 0.03) were associated with statistically significant mortality. Gestational age (odds ratio [OR]: 0.49, confidence interval [CI]: 0.26-0.90, P = 0.02), weight on admission (OR: 1.57, CI: 1.08-2.27, P = 0.01), age at admission (OR: 0.89, CI: 0.78-0.99, P = 0.04), distance travelled with neonate (OR: 1.01, CI: 1.00-1.01, P = 0.003), duration of hospital stay (OR: 0.69, CI: 0.63-0.74, P < 0.001), hypothermia (OR: 1.87, CI: 1.01-3.42, P = 0.04), convulsion (OR: 2.88, CI: 1.33-6.20, P = 0.007), cyanosis (OR: 2.39, CI: 1.07-5.35, P = 0.03) and prolonged capillary refill time (OR: 3.34, CI: 1.78-6.24, P < 0.001) were the independent predictors of mortality in neonatal sepsis. Conclusion: Gestational age; birth weight; long distance travelled with neonate and presentation with hypothermia, cyanosis, convulsions and prolonged capillary refill time were the independent risk factors for mortality in neonatal sepsis among outborns.


Assuntos
Sepse Neonatal/mortalidade , Peso ao Nascer , Sangue/microbiologia , Cianose , Feminino , Idade Gestacional , Humanos , Hipotermia , Incidência , Índia/epidemiologia , Recém-Nascido , Masculino , Sepse Neonatal/etiologia , Gravidez , Estudos Prospectivos , Fatores de Risco , Convulsões
3.
Nature ; 574(7779): 543-548, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31645720

RESUMO

Multicellular organisms have co-evolved with complex consortia of viruses, bacteria, fungi and parasites, collectively referred to as the microbiota1. In mammals, changes in the composition of the microbiota can influence many physiologic processes (including development, metabolism and immune cell function) and are associated with susceptibility to multiple diseases2. Alterations in the microbiota can also modulate host behaviours-such as social activity, stress, and anxiety-related responses-that are linked to diverse neuropsychiatric disorders3. However, the mechanisms by which the microbiota influence neuronal activity and host behaviour remain poorly defined. Here we show that manipulation of the microbiota in antibiotic-treated or germ-free adult mice results in significant deficits in fear extinction learning. Single-nucleus RNA sequencing of the medial prefrontal cortex of the brain revealed significant alterations in gene expression in excitatory neurons, glia and other cell types. Transcranial two-photon imaging showed that deficits in extinction learning after manipulation of the microbiota in adult mice were associated with defective learning-related remodelling of postsynaptic dendritic spines and reduced activity in cue-encoding neurons in the medial prefrontal cortex. In addition, selective re-establishment of the microbiota revealed a limited neonatal developmental window in which microbiota-derived signals can restore normal extinction learning in adulthood. Finally, unbiased metabolomic analysis identified four metabolites that were significantly downregulated in germ-free mice and have been reported to be related to neuropsychiatric disorders in humans and mouse models, suggesting that microbiota-derived compounds may directly affect brain function and behaviour. Together, these data indicate that fear extinction learning requires microbiota-derived signals both during early postnatal neurodevelopment and in adult mice, with implications for our understanding of how diet, infection, and lifestyle influence brain health and subsequent susceptibility to neuropsychiatric disorders.


Assuntos
Extinção Psicológica/fisiologia , Medo/fisiologia , Metabolômica , Microbiota/fisiologia , Neurônios/fisiologia , Animais , Antibacterianos/farmacologia , Transtorno Autístico/metabolismo , Sangue/metabolismo , Cálcio/metabolismo , Líquido Cefalorraquidiano/química , Líquido Cefalorraquidiano/metabolismo , Sinais (Psicologia) , Espinhas Dendríticas/efeitos dos fármacos , Espinhas Dendríticas/patologia , Espinhas Dendríticas/fisiologia , Extinção Psicológica/efeitos dos fármacos , Medo/efeitos dos fármacos , Fezes/química , Vida Livre de Germes , Indicã/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microbiota/efeitos dos fármacos , Microbiota/imunologia , Inibição Neural , Neuroglia/patologia , Neuroglia/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/imunologia , Neurônios/patologia , Fenilpropionatos/metabolismo , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/imunologia , Córtex Pré-Frontal/fisiologia , Esquizofrenia/metabolismo , Transcriptoma , Nervo Vago/fisiologia
4.
Malar J ; 18(1): 262, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31366365

RESUMO

BACKGROUND: The Mindray BC-6800 haematology analyzer (BC-6800) provides a dedicated flag 'Infected RBC' (InR) and the number of InR (InR#)/the permillage of InR (InR‰) in routine blood testing as a screening tool for malaria in endemic areas. This study sought to evaluate the effectiveness of the BC-6800 flag parameter for aiding the diagnosis of malaria. METHODS: A total of 181 samples were tested using the Mindray BC-6800 haematology analyzer, including 117 malaria-infected samples collected from Yunnan, China, and 64 samples from healthy controls. Microscopy examination was conducted as reference when stained thick blood film revealed the presence of malaria parasites identified as Plasmodium vivax and Plasmodium falciparum. The receiver operating characteristic (ROC) curve analysis was developed using Analyse-it v4.92.3. The Kappa value was determined to evaluate the agreement between BC-6800 and light microscopy. RESULTS: The sensitivity of InR‰ generated by BC-6800 for P. vivax and P. falciparum was 88.3 and 24.1%, respectively; specificity of InR‰ for malaria parasites was 84.3 and 84.3%, respectively; positive predictive value and negative predictive value was 89.4 and 82.7% for P. vivax, and 52.8 and 60.3% for P. falciparum. There was a strong correlation between ΔWBC and InR‰ (R2 = 0.9731 for P. vivax and R2 = 0.9757 for P. falciparum). There was also a significant correlation between parasitaemia and InR# in P. vivax-infected samples (R2 = 0.734). InR# was evaluated using ROC curve analysis, the area under the ROC curve is 0.95 with a 95% confidence interval of 0.926 to 0.974, and the cut-off value is 0.01 × 109/L for P. vivax. However, the ring stage and the early trophozoite stage of Plasmodium cannot be detected easily on BC-6800, possibly because of the small size and low nucleic acid content of these stages. CONCLUSIONS: The findings suggest that the flag 'InR' and the parameters 'InR#/InR‰' provided by the BC-6800 haematology analyzer could be used to screen for malaria in a clinical setting.


Assuntos
Análise Química do Sangue/métodos , Sangue/parasitologia , Hematologia/métodos , Malária Falciparum/diagnóstico , Malária Vivax/diagnóstico , Plasmodium falciparum/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Adolescente , Adulto , Idoso , Análise Química do Sangue/instrumentação , Criança , Pré-Escolar , China/epidemiologia , Feminino , Hematologia/instrumentação , Humanos , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Malária Vivax/epidemiologia , Malária Vivax/parasitologia , Masculino , Pessoa de Meia-Idade , Parasitemia/diagnóstico , Parasitemia/epidemiologia , Parasitemia/parasitologia , Prevalência , Curva ROC , Sensibilidade e Especificidade
5.
Emerg Microbes Infect ; 8(1): 1108-1121, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31340720

RESUMO

Human papillomaviruses (HPV) contribute to most cervical cancers and are considered to be sexually transmitted. However, papillomaviruses are often found in cancers of internal organs, including the stomach, raising the question as to how the viruses gain access to these sites. A possible connection between blood transfusion and HPV-associated disease has not received much attention. Here we show, in rabbit and mouse models, that blood infected with papillomavirus yields infections at permissive sites with detectable viral DNA, RNA transcripts, and protein products. The rabbit skin tumours induced via blood infection displayed decreased expression of SLN, TAC1, MYH8, PGAM2, and APOBEC2 and increased expression of SDRC7, KRT16, S100A9, IL36G, and FABP9, as seen in tumours induced by local infections. Furthermore, we demonstrate that blood from infected mice can transmit the infection to uninfected animals. Finally, we demonstrate the presence of papillomavirus infections and virus-induced hyperplasia in the stomach tissues of animals infected via the blood. These results indicate that blood transmission could be another route for papillomavirus infection, implying that the human blood supply, which is not screened for papillomaviruses, could be a potential source of HPV infection as well as subsequent cancers in tissues not normally associated with the viruses.


Assuntos
Sangue/virologia , Papillomaviridae/fisiologia , Infecções por Papillomavirus/transmissão , Infecções por Papillomavirus/virologia , Animais , DNA Viral/genética , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Papillomaviridae/genética , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/sangue , Infecções por Papillomavirus/genética , Coelhos
6.
J Forensic Sci ; 64(6): 1913-1915, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31283022

RESUMO

We present a case of a faux blood fingermark, wherein a natural latent fingerprint on the pistol at the crime scene was enhanced by the whole blood of the victim. A male was shot to death. The crime scene investigator did not find any blood fingermark during the collection of evidence, but a blood fingerprint was noticed in the firearms examination. We identified that the fingerprint was of the victim; a series of experiments on the nonporous substrate were then conducted; the death in this case was classified as a suicide. The phenomenon is interesting, and thus, calls for attention of the forensic community.


Assuntos
Sangue , Dermatoglifia , Armas de Fogo , Suicídio , Ciências Forenses/métodos , Humanos , Masculino
7.
Nature ; 571(7764): 205-210, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31270459

RESUMO

The mammalian brain contains neurogenic niches that comprise neural stem cells and other cell types. Neurogenic niches become less functional with age, but how they change during ageing remains unclear. Here we perform single-cell RNA sequencing of young and old neurogenic niches in mice. The analysis of 14,685 single-cell transcriptomes reveals a decrease in activated neural stem cells, changes in endothelial cells and microglia, and an infiltration of T cells in old neurogenic niches. T cells in old brains are clonally expanded and are generally distinct from those in old blood, which suggests that they may experience specific antigens. T cells in old brains also express interferon-γ, and the subset of neural stem cells that has a high interferon response shows decreased proliferation in vivo. We find that T cells can inhibit the proliferation of neural stem cells in co-cultures and in vivo, in part by secreting interferon-γ. Our study reveals an interaction between T cells and neural stem cells in old brains, opening potential avenues through which to counteract age-related decline in brain function.


Assuntos
Envelhecimento/fisiologia , Encéfalo/citologia , Movimento Celular , Células-Tronco Neurais/citologia , Neurogênese , Análise de Célula Única , Nicho de Células-Tronco/fisiologia , Linfócitos T/citologia , Animais , Sangue , Proliferação de Células , Células Clonais/citologia , Técnicas de Cocultura , Células Endoteliais/citologia , Interferon gama/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia , Análise de Sequência de RNA , Transdução de Sinais , Linfócitos T/metabolismo , Transcriptoma/genética
8.
Anal Chim Acta ; 1077: 288-296, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31307721

RESUMO

Rapid and reliable detection of pathogenic bacteria is vital to prevent and control bacterial diseases. In this study, we present a magnetically assisted surface-enhanced Raman scattering (SERS) biosensor based on the dual-recognition of bacterial cell by aptamer and antibiotic molecules. Aptamer-Fe3O4@Au magnetic nanoparticles (AuMNPs) were synthesized as magnetic and SERS activated substrate for specific bacteria enrichment, vancomycin-SERS tags (Au@MBA) were prepared for the sensitive quantification of pathogenic bacteria. Due to the Au-shell based dual-SERS enhancement and aptamer/vancomycin based dual-recognition ability, a detection limit of 3 cells/mL with a wide dynamic linear range from 10 to 107 cells/mL can be achieved within 50 min without other non-target bacteria interference. When applied in real samples, the approach shows recoveries from 95.0% to 106.4% with relative standard derivation (RSD) less than 5.3%. The SERS strategy could be used to detect a broad range of bacteria by using different aptamers, moreover, the simple operation and precise quantification ability empower this assay great potential in the application of food safety and infectious disease point-of-care diagnosis.


Assuntos
Aptâmeros de Nucleotídeos/química , Óxido Ferroso-Férrico/química , Ouro/química , Nanopartículas Metálicas/química , Staphylococcus aureus/isolamento & purificação , Vancomicina/química , Animais , Benzoatos/química , Técnicas Biossensoriais/métodos , Sangue/microbiologia , Contaminação de Alimentos/análise , Sucos de Frutas e Vegetais/microbiologia , Humanos , Limite de Detecção , Leite/microbiologia , Reprodutibilidade dos Testes , Análise Espectral Raman/métodos , Compostos de Sulfidrila/química
9.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(5): 629-632, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31198153

RESUMO

OBJECTIVE: To investigate the detection and distribution of hospitalized specimens from a tertiary hospital over 5 years. METHODS: Specimens of sputum, urine, blood, secretions and puncture fluid were collected from patients admitted to the Harrison International Peace Hospital from November 2013 to November 2018. The origin of specimens, the distribution of departments and the distribution of pathogenic bacteria isolated were analyzed retrospectively. RESULTS: A total of 61 286 specimens were sent for examination during the 5 years. The top 5 specimens were sputum culture (n = 18 302, 29.9%), sputum smear (n = 11 253, 18.4%), blood culture (n = 9 713, 15.8%), urine culture (n = 6 448, 10.5%) and secretion culture (n = 6 133, 10.0%), accounting for 84.6% (51 849/61 286). Sputum specimens accounted for 48.2% (29 555/61 286) with the largest proportion. The number of specimens from medical wards was much higher than that from surgical wards (specimens: 25 468 vs. 10 521), respiratory medicine, department of critical care medicine and emergency intensive care unit (EICU) were important sources of pathogenic specimens in the hospital, accounting for 29.8% (18 243/61 286) in total. The average positive rate of all specimens was 23.5% (14 424/61 286). The positive rates of sputum culture and urine culture were 29.7% (5 428/18 302) and 35.4% (2 281/6 448), respectively, while the positive rate of blood culture was only 6.6% (643/9 713). Escherichia coli was the most common pathogen in all specimens except for sputum culture and fecal culture. Escherichia coli [40.6% (926/2 281)], Klebsiella pneumoniae [9.2% (210/2 281)], Pseudomonas aeruginosa [8.2% (188/2 281)], Enterococcus faecalis (group D) [6.6% (151/2 281)] and Candida albicans [3.2% (73/2 281)] were the most common pathogens in urine culture. Klebsiella pneumoniae [24.1% (1 309/5 428)], Acinetobacter baumannii [21.3% (1 154/5 428)], Pseudomonas aeruginosa [15.1% (818/5 428)], Escherichia coli [6.5% (351/5 428)] and Maltose oligotrophomonas maltose [5.8% (316/5 428)] were the most common pathogens in sputum culture. Escherichia coli [36.5% (235/643)], Klebsiella pneumoniae [10.9% (70/643)], Pseudomonas aeruginosa [4.8% (31/643)], Staphylococcus epidermidis [3.4% (22/643)] and Staphylococcus humanis [3.3% (21/643)] were the most common pathogens in blood culture. CONCLUSIONS: Specimens sent for examination by inpatients are mainly from internal medicine wards, mainly from sputum, blood and urine, and the detected pathogens are mainly Gram-negative bacteria.


Assuntos
Manejo de Espécimes/estatística & dados numéricos , Centros de Atenção Terciária , Sangue/microbiologia , Bactérias Gram-Negativas/isolamento & purificação , Hospitalização , Humanos , Medicina Interna/estatística & dados numéricos , Estudos Retrospectivos , Escarro/microbiologia , Urina/microbiologia
10.
Sud Med Ekspert ; 62(3): 33-36, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31198202

RESUMO

The aim of this study was to identify the peculiarities of blood droplets on the street in frosty weather on the surfaces of objects with a negative temperature. The effect of negative ambient temperature (-19 °C) on the morphology of blood droplet traces was experimentally established. On cold trace surfaces, the droplet footprint was smaller, relatively flat and with wave-shaped edges; there was no splashing. Such a morphological presentation in frosty weather arises from the rapid cooling of the falling drop of blood which crystallizes in contact with the cold surface. There was no complete spreading of liquid droplets. The data obtained should be taken into account when assessing the traces of blood droplets detected at the scene of the incident on the street in winter, in order to avoid expert errors in determining their mechanism and the height of the blood source.


Assuntos
Sangue , Temperatura Baixa , Patologia Legal , Humanos , Propriedades de Superfície
11.
Microb Pathog ; 135: 103566, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31252065

RESUMO

BACKGROUND: Breast cancer is one of the most common cancers in the world particularly among Iranian women. Bovine leukemia virus (BLV) is an enzootic, exogenous, and oncogenic retrovirus that causes B-cell leukosis in 1-5% of infected cattle. The current study aimed at evaluating the correlation between BLV infection and breast cancer in an Iranian population. MATERIALS AND TECHNIQUES: A total of 400 samples including 200 breast cancer-suspected tissue samples and 200 blood samples of women without breast cancer, were collected from July 2017 to October 2018 from women referred to two general hospitals in Qom Province, Iran. The nested PCR technique was performed to determine the presence of tax and gag gene of BLV in the collected samples. RESULTS: Out of 200 breast cancer-suspected tissue samples, 172 samples were malignant in terms of pathology. Other samples were reported as non-malignant and non-tumor. Based on nested PCR technique, tax and gag genes of BLV were detected in 30% and 8% of breast cancer-suspected tissue samples, respectively. The frequency of BLV in blood samples collected from women without breast cancer was 16.5% (33/200). CONCLUSION: It seems that human breast cancer and BLV infection in cattle could be associated using nested PCR technique.


Assuntos
Sangue/virologia , Mama/virologia , Infecções por Deltaretrovirus/virologia , Vírus da Leucemia Bovina/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/patologia , Neoplasias da Mama/sangue , Neoplasias da Mama/virologia , DNA Viral/análise , Infecções por Deltaretrovirus/epidemiologia , Feminino , Genes gag , Genes pX , Humanos , Irã (Geográfico)/epidemiologia , Vírus da Leucemia Bovina/genética , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
12.
Medicine (Baltimore) ; 98(25): e16079, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31232949

RESUMO

Clinical signs and symptoms of central nervous system (CNS) infections in neonates are often nonspecific. Therefore, cerebrospinal fluid (CSF) analysis is performed to diagnose CNS infections. Data on combined microbiological results and their correlation with biochemical characteristics in CSF and blood in infants younger than 90 days are limited. This study provides an overview of microbiological test results, CSF- and hematological characteristics among infants with a clinically suspected CNS infection.This retrospective study included infants younger than 90 days, with a clinically suspected CNS infection who underwent a diagnostic lumbar puncture between January 2012 and January 2014. Data on the presence of microbiological pathogens in CSF, CSF inflammation markers (white blood cell [WBC] counts, protein levels and glucose CSF/serum ratio) and blood inflammatory responses (WBC count, C-reactive protein [CRP], neutrophil percentage) were collected by reviewing patient files.We included data from 576 infants (median age 12.5 days, interquartile range, 6-27 days) of whom 383 (66.5%) were born prematurely. In total, 16 bacterial pathogens (3.0%) and 21 viruses (5.5%) were detected in CSF. Escherichia coli was detected in 5 cases (1.0%), Enterovirus was detected in 12 cases (3.1%). Leucocytosis in CSF was associated with identification of a pathogen in CSF. Increased CRP was associated with the identification of a bacterial pathogen in CSF.Bacterial or viral pathogens were only identified in a small proportion of infants with a clinically suspected CNS infection. Leucocytosis in CSF was associated with CNS infection in infants. An increased CRP was indicative of bacterial meningitis.


Assuntos
Sangue/microbiologia , Infecções do Sistema Nervoso Central/sangue , Infecções do Sistema Nervoso Central/líquido cefalorraquidiano , Líquido Cefalorraquidiano/microbiologia , Infecções do Sistema Nervoso Central/fisiopatologia , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Países Baixos , Estudos Retrospectivos , Estatísticas não Paramétricas
13.
Radiat Res ; 192(2): 189-199, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31237816

RESUMO

In the possible event of a detonation of an improvised nuclear device (IND), the immediate radiation would consist of both photons (gamma rays) and neutrons. Since neutrons generally have a high relative biological effectiveness (RBE) for most physiological end points, it is important to understand the effect that neutrons would have on the biodosimetry methods that are being developed for medical triage purposes. We previously compared the transcriptomic response in human blood after neutron and photon irradiation. In this study, we analyzed the effect of mixed-field-neutron-photon radiation on gene expression responses in human peripheral blood, to elucidate the neutron contribution in the setting of a radiation exposure from an IND detonation. We used four combinations of mixed neutron-photon exposures, with increasing percentages of neutrons, to a cumulative dose of 3 Gy. The mixed-field exposures consisted of 0%, 5%, 15% and 25% of neutrons, where 0% corresponds to 3 Gy of pure X rays. A maximum neutron exposure, corresponding to 83% neutrons (0.75 Gy) was also used in the study. Increases were observed in both the number and expression level of genes, with increasing percentages of neutrons from 0% to 25% in the mixed-field exposures. Gene ontology analysis showed an overall predominance of TP53 signaling among upregulated genes across all exposures. Some TP53 regulated genes, such as EDA2R, GDF15 and VWCE, demonstrated increased expression with increasing neutron percentages in mixed-field exposures. Immune response, specifically natural-killer-cell mediated signaling, was the most significant biological process associated with downregulated genes. We observed significant suppression of T-cell-mediated signaling in mixed-field exposures, which was absent in the response to pure photons. In this first study investigating gene expression in human blood cells exposed to mixed neutron-photon fields similar to an actual IND explosion, we have identified a number of genes responding to the 3 Gy dose that showed increasing expression as the neutron percentage increased. Such genes may serve as better indicators of the expected biological damage than a report of total physical dose, and thus provide more relevant information for treating physicians.


Assuntos
Nêutrons/efeitos adversos , Fótons/efeitos adversos , Exposição à Radiação/efeitos adversos , Transcriptoma/efeitos da radiação , Sangue/metabolismo , Sangue/efeitos da radiação , Ontologia Genética , Voluntários Saudáveis , Humanos , Eficiência Biológica Relativa
14.
Malar J ; 18(1): 192, 2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31185976

RESUMO

BACKGROUND: Mutational analysis of the Plasmodium falciparum kelch 13 (k13) gene is routinely performed to track the emergence and spread of artemisinin resistance. Surveillance of resistance markers has been impeded by the difficulty of extracting sufficient DNA from low parasite density infections common in low-transmission settings, such as Southeast Asia. This problem can be overcome by collecting large volumes of venous blood. Efficient methods for extracting and amplifying k13 from dried blood spots (DBS) would facilitate resistance surveillance. METHODS: Methods for k13 amplification from standard Whatman 3MM DBS (stored for 14 days at 28 °C with 80% relative humidity) were optimized by systematically testing different extraction conditions. Conditions that improved parasite DNA recovery as assessed by quantitative polymerase chain reaction (PCR) of 18S rDNA were then tested for their impact on k13 PCR amplification. RESULTS: The optimized protocol for amplification of k13 from DBS is markedly more sensitive than standard methods using commercial kits. Using this method, k13 was successfully amplified from laboratory-created DBS samples with parasite densities as low as 500 parasites/mL. Importantly, the method recovers both DNA and RNA, making it compatible with RNA-based ultrasensitive techniques currently in use. CONCLUSIONS: The optimized DBS protocol should facilitate drug resistance surveillance, especially in low-transmission settings where clinical malaria infections with high parasite densities are rare.


Assuntos
Artemisininas/farmacologia , Sangue/parasitologia , DNA de Protozoário/isolamento & purificação , Resistência a Medicamentos , Malária Falciparum/parasitologia , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Antimaláricos/farmacologia , Ásia Sudeste , DNA de Protozoário/química , DNA de Protozoário/genética , Dessecação/métodos , Humanos , Plasmodium falciparum/efeitos dos fármacos , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Manejo de Espécimes/métodos
15.
J S Afr Vet Assoc ; 90(0): e1-e5, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31170779

RESUMO

Equid herpesvirus type 1 is primarily a respiratory tract virus associated with poor athletic performance that can also cause late gestation abortion, neonatal foal death and encephalomyelopathy. Horizontal transmission is well described, whereas evidence of vertical transmission of equid herpesvirus type 1 associated with the birth of a healthy foal has not been demonstrated. This study sampled a population of Thoroughbred mares (n = 71), and their healthy neonatal foals and foetal membranes, to test for the presence of both equid herpesvirus types 1 and 4 using a quantitative polymerase chain reaction assay. Foetal membrane swabs and tissue samples were taken immediately post-partum, and venous blood samples and nasal swabs were obtained from both mare and foal 8 h after birth. Neither equid herpesvirus type 1 nor equid herpesvirus type 4 nucleic acid was detected in any sample, and it was concluded that there was no active shedding of equid herpesvirus types 1 and 4 at the time of sampling. Consequently, no evidence of vertical transmission of these viruses could be found on this stud farm during the sampling period.


Assuntos
Animais Recém-Nascidos/virologia , Infecções por Herpesviridae/veterinária , Herpesvirus Equídeo 1/isolamento & purificação , Herpesvirus Equídeo 4/isolamento & purificação , Doenças dos Cavalos/virologia , Animais , Sangue/virologia , Feminino , Infecções por Herpesviridae/transmissão , Doenças dos Cavalos/transmissão , Cavalos , Transmissão Vertical de Doença Infecciosa/veterinária , Mucosa Nasal/virologia , Placenta/virologia , Reação em Cadeia da Polimerase/veterinária , Gravidez , África do Sul/epidemiologia
16.
Parasit Vectors ; 12(1): 297, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31196161

RESUMO

BACKGROUND: Effective malaria control relies on evidence-based interventions. Anopheline behaviour and Plasmodium infections were investigated in North Cameroon, following long-lasting insecticidal net (LLIN) distribution in 2010. METHODS: During four consecutive years from 2011 to 2014, adult mosquitoes were collected indoors, outdoors and in exit traps across 38 locations in the Garoua, Pitoa and Mayo-Oulo health districts. Anophelines were morphologically and molecularly identified, then analysed for blood meal origins and Plasmodium falciparum circumsporozoite protein (Pf-CSP). Blood from children under 5 years-old using LLINs was examined for Plasmodium infections. RESULTS: Overall, 9376 anophelines belonging to 14 species/sibling species were recorded. Anopheles gambiae (s.l.) [An. arabiensis (73.3%), An. coluzzii (17.6%) and An. gambiae (s.s.) (9.1%)] was predominant (72%), followed by An. funestus (s.l.) (20.5%) and An. rufipes (6.5%). The recorded blood meals were mainly from humans (28%), cattle (15.6%) and sheep (11.6%) or mixed (45%). Pf-CSP rates were higher indoors (3.2-5.4%) versus outdoors (0.8-2.0%), and increased yearly (χ2 < 18, df = 10, P < 0.03). Malaria prevalence in children under 5 years-old, in households using LLINs was 30% (924/3088). CONCLUSIONS: The present study revealed the variability of malaria vector resting and feeding behaviour, and the persistence of Plasmodium infections regardless the use of LLINs. Supplementary interventions to LLINs are therefore needed to sustain malaria prevention in North Cameroon.


Assuntos
Anopheles/fisiologia , Controle de Doenças Transmissíveis , Comportamento Alimentar , Malária Falciparum/prevenção & controle , Animais , Anopheles/parasitologia , Sangue/parasitologia , Camarões/epidemiologia , Mosquiteiros Tratados com Inseticida , Malária Falciparum/epidemiologia , Controle de Mosquitos , Mosquitos Vetores/parasitologia , Mosquitos Vetores/fisiologia , Plasmodium falciparum , Proteínas de Protozoários/genética
17.
Malar J ; 18(1): 187, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31146762

RESUMO

BACKGROUND: The propensity of different Anopheles mosquitoes to bite humans instead of other vertebrates influences their capacity to transmit pathogens to humans. Unfortunately, determining proportions of mosquitoes that have fed on humans, i.e. Human Blood Index (HBI), currently requires expensive and time-consuming laboratory procedures involving enzyme-linked immunosorbent assays (ELISA) or polymerase chain reactions (PCR). Here, mid-infrared (MIR) spectroscopy and supervised machine learning are used to accurately distinguish between vertebrate blood meals in guts of malaria mosquitoes, without any molecular techniques. METHODS: Laboratory-reared Anopheles arabiensis females were fed on humans, chickens, goats or bovines, then held for 6 to 8 h, after which they were killed and preserved in silica. The sample size was 2000 mosquitoes (500 per host species). Five individuals of each host species were enrolled to ensure genotype variability, and 100 mosquitoes fed on each. Dried mosquito abdomens were individually scanned using attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectrometer to obtain high-resolution MIR spectra (4000 cm-1 to 400 cm-1). The spectral data were cleaned to compensate atmospheric water and CO2 interference bands using Bruker-OPUS software, then transferred to Python™ for supervised machine-learning to predict host species. Seven classification algorithms were trained using 90% of the spectra through several combinations of 75-25% data splits. The best performing model was used to predict identities of the remaining 10% validation spectra, which had not been used for model training or testing. RESULTS: The logistic regression (LR) model achieved the highest accuracy, correctly predicting true vertebrate blood meal sources with overall accuracy of 98.4%. The model correctly identified 96% goat blood meals, 97% of bovine blood meals, 100% of chicken blood meals and 100% of human blood meals. Three percent of bovine blood meals were misclassified as goat, and 2% of goat blood meals misclassified as human. CONCLUSION: Mid-infrared spectroscopy coupled with supervised machine learning can accurately identify multiple vertebrate blood meals in malaria vectors, thus potentially enabling rapid assessment of mosquito blood-feeding histories and vectorial capacities. The technique is cost-effective, fast, simple, and requires no reagents other than desiccants. However, scaling it up will require field validation of the findings and boosting relevant technical capacity in affected countries.


Assuntos
Anopheles/fisiologia , Mosquitos Vetores/fisiologia , Espectrofotometria Infravermelho , Aprendizado de Máquina Supervisionado , Vertebrados/sangue , Animais , Sangue , Galinhas/sangue , Comportamento Alimentar , Feminino , Cabras/sangue , Especificidade de Hospedeiro , Humanos , Modelos Logísticos , Malária/sangue
18.
Parasitol Res ; 118(8): 2409-2417, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31197543

RESUMO

Human babesiosis, a tick-borne disease similar to malaria, is most often caused by the hemoprotozoans Babesia divergens in Europe, and Babesia microti and Babesia duncani in North America. Babesia microti is the best documented and causes more cases of human babesiosis annually than all other agents combined. Although the agents that cause human babesiosis are considered high-risk pathogens in transfusion medicine, federally licensed diagnostics are lacking for B. duncani in both the USA and Canada. Thus, there has been a need to develop and validate diagnostics specifically for this pathogen. In this study, B. duncani (WA1 isolate) was cultivated in vitro from Syrian hamster (Mesocricetus auratus) infected blood. We hypothesized HL-1 media with supplements would result in B. duncani propagating at higher levels in culture than supplemented M199 similar to the medium the parasite was originally cultivated with in 1994. We were unable to recreate Thomford's cultivation results with the M199 medium but supplemented HL-1 medium was able to successfully establish continuous culture. We further hypothesized that RBC from species other than hamsters would support B. duncani in vitro. However, rat, mouse, horse, and cow RBC did not support continuous culture of the parasite. Culture stocks of B. duncani were deposited at BEI Resources and are now commercially available to the scientific community to further research. The cultured parasite developed in this study was instrumental in the adaptation of B. duncani continuous culture to human RBC.


Assuntos
Babesia microti/crescimento & desenvolvimento , Babesiose/parasitologia , Sangue/parasitologia , Zoonoses/parasitologia , Animais , Babesia/crescimento & desenvolvimento , Babesia/isolamento & purificação , Babesia microti/isolamento & purificação , Babesiose/sangue , Canadá , Bovinos , Cricetinae , Europa (Continente) , Feminino , Cavalos , Humanos , Masculino , Camundongos , América do Norte , Ratos , Zoonoses/sangue
19.
Parasit Vectors ; 12(1): 316, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31234905

RESUMO

BACKGROUND: Juvenile gnathiid isopods are common ectoparasites of marine fishes. Each of the three juvenile stages briefly attach to a host to obtain a blood meal but spend most of their time living in the substrate, thus making it difficult to determine patterns of host exploitation. Sequencing of host blood meals from wild-caught specimens is a promising tool to determine host identity. Although established protocols for this approach exist, certain challenges must be overcome when samples are subjected to typical field conditions that may contribute to DNA degradation. The goal of this study was to address a key methodological issue associated with molecular-based host identification from free-living, blood-engorged gnathiid isopods-the degradation of host DNA within blood meals. Here we have assessed the length of time host DNA within gnathiid blood meals can remain viable for positive host identification. METHODS: Juvenile gnathiids were allowed to feed on fish of known species and subsets were preserved at 4-h intervals over 24 h and then every 24 h up to 5 days post-feeding. Host DNA extracted from gnathiid blood meals was sequenced to validate the integrity of host DNA at each time interval. DNA was also extracted from blood meals of wild-fed gnathiids for comparison. Attempts were also made to extract host DNA from metamorphosed juveniles. RESULTS: Using a cox1 universal fish primer set, known fish host DNA sequences were successfully identified for nearly 100% of third-stage juvenile gnathiid blood meals, digested for up to 5 days post-feeding. For second-stage juveniles, host identification was 100% successful when gnathiids were preserved within 24 h of collection. Fish hosts were positively identified for 69% of sequences from wild-fed gnathiid isopods. Of the 31% of sequences not receiving a ≥ 98 % match to a sequence in GenBank, 25 sequences were of possible invertebrate origin. CONCLUSIONS: To our knowledge, this is the first study to examine the degradation rate of gnathiid isopod blood meals. Determining the rate at which gnathiids digest their blood meal is an important step in ensuring the successful host identification by DNA-based methods in large field studies.


Assuntos
DNA/química , Peixes/genética , Peixes/parasitologia , Isópodes/fisiologia , Animais , Sangue , Comportamento Alimentar , Doenças dos Peixes/parasitologia , Larva , Masculino
20.
Mem Inst Oswaldo Cruz ; 114: e190047, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31166422

RESUMO

OBJECTIVES: We tested a rapid and specific immunochromatographic assay (that detects human blood in forensic samples) to determine if human blood was present in triatomines and their fecal excreta. METHODS: We fed Triatoma rubida human blood (positive control) or mouse blood (negative control) and performed the assay on the abdominal contents and fecal excreta. Triatomine field specimens collected in and around human habitations and excreta were also tested. FINDINGS: The assay was positive in triatomines fed human blood (N = 5/5) and fecal excreta from bugs known to have ingested human blood (N = 5/5). Bugs feeding on mice (N = 15/15) and their fecal excreta (N = 8/8) were negative for human blood. Human blood was detected in 47% (N = 23/49) triatomines, representing six different species, collected in the field. MAIN CONCLUSIONS: The pilot study shows that this rapid and specific test may have applications in triatomine research. Further study is needed to determine the sensitivity of this assay compared to other well-established techniques, such as DNA- and proteomics-based methodologies and the assay's application in the field.


Assuntos
Sangue , Fezes/química , Imunoensaio/métodos , Triatominae , Animais , Doença de Chagas/transmissão , Humanos , Camundongos , Projetos Piloto , Padrões de Referência , Valores de Referência , Reprodutibilidade dos Testes , Fatores de Tempo
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