Search results for "Molecular Epidemiology"
showing 10 items of 142 documents
Changing distribution of norovirus genotypes and genetic analysis of recombinant GIIb among infants and children with diarrhea in Japan
2006
A total of 402 fecal specimens collected during July 2003-June 2004 from infants and children with acute gastroenteritis, encompassing five localities (Maizuru, Tokyo, Sapporo, Saga, and Osaka) of Japan, were tested for the presence of norovirus by RT-PCR. It was found that 58 (14.4%) fecal specimens were positive for norovirus. Norovirus infection was detected throughout the year with the highest prevalence in December. Norovirus GII was the most predominant genogroup (98.3%; 57 of 58). The genotypes detected in this study were GI/4, GII/2, GII/3, GII/4, and GII/6. Of these, NoV GII/3 (known as the Arg320 virus cluster) was the most predominant genotype (43.9%), followed by NoV GII/4 (the …
Molecular characterization of rotavirus strains from children with diarrhea in Italy, 2007-2009.
2011
The surveillance network RotaNet-Italia was established in 2007 in order to investigate the diversity of co-circulating rotavirus strains in Italy, and to provide a baseline for future assessment of possible effects of vaccine implementation in selecting novel versus common rotavirus strains. A total of 2,645 rotavirus strains from pediatric patients with acute diarrhea were collected over three consecutive seasons from September 2006 through August 2009, and partially characterized by standardized multiplex RT-PCR. Most of strains (89.1%) belonged to genotypes G1–G4, and G9, associated with either P[8] or P[4], commonly found in humans worldwide. However, in at least 2.0% of cases, viruses…
Distribution of VP7 serotypes and VP4 genotypes among rotavirus strains recovered from Italian children with diarrhea
1997
108 rotavirus strains obtained from children with diarrhea hospitalized in Palermo, Italy, in the years 1990-1994, were examined by seminested PCR to study the relative frequency and distribution of the four most common alleles of the gene 4. Such strains were selected from 344 human rotavirus strains recovered in palermo during those years after characterization by electropherotyping, subgrouping and G serotyping. One hundred and seven of the 108 strains could be classified into P types, the P[8], G1 (38.3%) and the P[8], G4 (52.3%) types being predominant. The unique strain whose P genotype could not be identified showed an unusual combination of long migration electrophoretic pattern and…
Lymnaea schirazensis, an Overlooked Snail Distorting Fascioliasis Data: Genotype, Phenotype, Ecology, Worldwide Spread, Susceptibility, Applicability
2011
BackgroundLymnaeid snails transmit medical and veterinary important trematodiases, mainly fascioliasis. Vector specificity of fasciolid parasites defines disease distribution and characteristics. Different lymnaeid species appear linked to different transmission and epidemiological patterns. Pronounced susceptibility differences to absolute resistance have been described among lymnaeid populations. When assessing disease characteristics in different endemic areas, unexpected results were obtained in studies on lymnaeid susceptibility to Fasciola. We undertook studies to understand this disease transmission heterogeneity.Methodology/principal findingsA ten-year study in Iran, Egypt, Spain, t…
Prevalence of Angelman syndrome and Prader-Willi syndrome in Estonian children: sister syndromes not equally represented.
2006
In 2000-2004, we performed a focused search for individuals with Angelman syndrome (AS) and Prader-Willi syndrome (PWS) aiming to establish the prevalence data for the individuals born between 1984 and 2004 in Estonia. All persons with probable AS or PWS (n = 184) were studied using the DNA methylation test. Individuals with abnormal methylation were all further tested by chromosomal and FISH analysis, and if necessary for uniparental disomy and UBE3A gene mutation. Nineteen cases with abnormal methylation test result were identified. Seven of them had AS, including six (85.7%) due to 15q11-13 deletion and one paternal UPD15. Twelve subjects had PWS: 4 (33%) 15q11-13 deletions, 6 (50%) mate…
Sequential variation in genomic RNA patterns of human rotaviruses isolated from infantile gastroenteritis
1986
The incidence and RNA electrophoretypes of rotaviral isolates obtained from infants and young children with acute gastroenteritis were studied from October, 1985 through April, 1986. Analysis of the viral RNA was carried out by Polyacrylamide gel electrophoresis followed by silver staining. Fourteen electrophoretypes were identified. A single dominant electrophoretype was found during the first months of the rotavirus seasonal outbreak. In contrast, a large variety of RNA patterns were observed during the latter portion of the study period. Subgrouping of rotavirus isolates by a double-sandwich enzyme-linked immunosorbent assay using monoclonal-detecting antibodies showed that all strains b…
Molecular epidemiology and forensic genetics: application to a hepatitis C virus transmission event at a hemodialysis unit.
2002
Molecular phylogenetic analyses are frequently used in epidemiologic testing, although only occasionally in forensics. Their acceptability is hampered by a lack of statistical confidence in the conclusions. However, maximum likelihood testing provides a sound statistical framework for the testing of phylogenetic hypotheses relevant for forensic analysis. We present the results of applying this method to a small hepatitis C outbreak produced in a hospital hemodialysis unit that involved 6 patients. Polymerase chain reaction products from a 472-nt fragment of the E1-E2 region, including the hypervariable region, HVR-1, of the hepatitis C virus genome were cloned, and an average of 10 clones/p…
Molecular characterization of fasciola spp. From some parts of Iran
2020
Background: Identification of liver flukes, Fasciola hepatica, and Fasciola gigantica by morphometric parameters is not always reliable due to the overlapping measurements. This study aimed to characterize the liver flukes of animals from different parts of Iran by the genetic markers, ITS1, and COXI. Methods: We collected flukes from infected livestock in six provinces of Iran from Sep to Nov 2016. The flukes were identified by amplification of a 680 bp sequence of ITS1 locus followed by a restriction fragment polymorphism (RFLP) assay. The genetic diversity among isolates was evaluated by amplification and sequencing of a 493 bp fragment of the COXI gene. Results: We obtained 38 specimens…
Genetic Variability and Phylogenetic Relationships within Trypanosoma cruzi I Isolated in Colombia Based on Miniexon Gene Sequences
2010
Phylogenetic studies ofTrypanosoma cruzihave identified the existence of two groups:T. cruziI andT. cruziII. There are aspects that still remain unknown about the genetic variability within theT. cruziI group. Given its epidemiological importance, it is necessary to have a better understanding ofT. cruzitransmission cycles. Our purpose was to corroborate the existence of haplotypes within theT. cruziI group and to describe the genetic variability and phylogenetic relationships, based on single nucleotide polymorphisms (SNPs) found in the miniexon gene intergenic region, for the isolates from different hosts and epidemiological transmission cycles in Colombian regions. 31T. cruziisolates wer…
S2k Guidelines for Cutaneous Basal Cell Carcinoma - Part 1: Epidemiology, Genetics and Diagnosis
2018
Basal cell carcinoma is the most common malignant tumor among fair-skinned individuals, and its incidence has been rising steadily in the past decades. In order to maintain the highest quality of patient care possible, the German S2k guidelines were updated following a systematic literature search and with the participation of all professional societies and associations involved in the management of the disease. Part 1 highlights new developments in genetics in particular as well as aspects regarding epidemiology, diagnosis, and histology.