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71.
72.
BACKGROUND: Hepatitis E virus (HEV) has been found to be the causative agent of enterically transmitted non-A, non-B hepatitis in tropical and subtropical countries. Several investigators, however, have indicated that HEV could be endemic in Europe, albeit at a low prevalence. STUDY DESIGN AND METHODS: The purpose of this study was to estimate the prevalence of anti-HEV in various populations in northwestern Greece (Epirus region). Healthy blood donors (2636), refugees from southern Albania (350), children (165), injecting drug users (IDUs) (65), multiply transfused patients (62), patients with chronic viral hepatitis (75), and chronic hemodialysis patients (149) were investigated for anti-HEV by enzyme immunoassay and confirmatory Western blot assay. In addition, 380 consecutive healthy blood donors and 62 hemodialysis patients from a neighboring area (Agrinion, Greece) were investigated. RESULTS: A very low presence of anti-HEV antibody was found among healthy blood donors from Epirus (0.23%) and Agrinion (0.53%). Anti-HEV was not detected in children, IDUs, or multiply transfused patients. In contrast, a low but significant prevalence of anti-HEV was found among refugees (4.85%), patients with chronic viral hepatitis (5.3%), and hemodialysis patients from Epirus (1.34%), as compared with healthy blood donors from Epirus: p < 0.0001, p < 0.00001, and p < 0.10, respectively. A high prevalence (9.7%) of anti- HEV was revealed in patients at the hemodialysis unit of the General Hospital of Agrinion (p < 0.00005, compared to healthy blood donors from Agrinion). No significant association was found between anti-HEV positivity and the age or sex of donors, the duration of hemodialysis, positivity for hepatitis B or C virus infection markers, history of hepatitis, increased alanine aminotransferase, renal transplantation, a history of transfusion, or the number of units transfused. CONCLUSION: This study demonstrated a high prevalence of anti-HEV in a separate hemodialysis unit, without an association with the known routes of transmission of blood-borne viruses. This observation suggests that a still-undefined intra-unit factor or other factors are associated with HEV transmission.  相似文献   
73.
Ganz  T; Liu  L; Valore  EV; Oren  A 《Blood》1993,82(2):641-650
Human defensins are 29 to 30 amino acid (aa) antimicrobial peptides that are among the principal constituents of the neutrophil's azurophil granules. To determine the tissue specificity of posttranslational processing and subcellular targeting of defensins, the cDNA for a 94 aa human preprodefensin was transduced into murine cell lines (NIH 3T3 embryonic fibroblasts, AtT-20 pituitary adenoma, J774.1 and RAW 264.7 macrophages, and 32D and 32D cl3 granulocytes) using retroviral vectors. All transduced cell types expressed and to a variable extent constitutively secreted a 75 aa prodefensin formed by the removal of the amino terminal signal sequence. In AtT-20 cells, the 75 aa form accumulated intracellularly in granules and was releasable by secretagogues. Proteolytic processing to mature defensins was seen only in myeloid cells (J774.1, RAW 264.7, 32D, and 32D cl3). Newly formed mature defensin was rapidly degraded in J774.1 and RAW 264.7 macrophages, but accumulated stably in multivesicular bodies in 32D cells and in cytoplasmic granules of 32D cl3 cells. Our data suggest that the enzymatic and transport machinery required to process preprodefensin to mature defensin and to store it in cytoplasmic granules is a specialized feature of cells of granulocytic lineage.  相似文献   
74.
A method for obtaining a stable colloidal solution of silver oxide nanoparticles has been developed using laser ablation. The method allows one to obtain nanoparticles with a monomodal size distribution and a concentration of more than 108 nanoparticles per mL. On the basis of the obtained nanoparticles and the PLGA polymer, a nanocomposite material was manufactured. The manufacturing technology allows one to obtain a nanocomposite material without significant defects. Nanoparticles are not evenly distributed in the material and form domains in the composite. Reactive oxygen species (hydrogen peroxide and hydroxyl radical) are intensively generated on the surfaces of the nanocomposite. Additionally, on the surface of the composite material, an intensive formation of protein long-lived active forms is observed. The ELISA method was used to demonstrate the generation of 8-oxoguanine in DNA on the developed nanocomposite material. It was found that the multiplication of microorganisms on the developed nanocomposite material is significantly decreased. At the same time, the nanocomposite does not inhibit proliferation of mammalian cells. The developed nanocomposite material can be used as an affordable and non-toxic nanomaterial to create bacteriostatic coatings that are safe for humans.  相似文献   
75.

Aim-Background

Infected pancreatic necrosis (IPN) develops in approximately one third of patients with necrotizing pancreatitis (NP). In the past, open necrosectomy (ON) was the standard treatment for this condition, but it carried significant morbidity and mortality. Currently, minimally invasive procedures (MIPs) have been established for the management of IPN, decreasing the risk of complications compared with ON.

Methods

A prospective study was made of patients with IPN treated by a MIP for necrosectomy via a percutaneous drainage catheter, followed by video-assisted retroperitoneal debridement (VARD).

Results

Between 2013 and 2016, 3 consecutive patients, with a mean age of 58 years, underwent a MIP for the management of IPN. All 3 patients had left lateral retroperitoneal pockets of necrosis, and the first-line procedure consisted of placement of a pigtail catheter. The drain tract was subsequently used to carry out VARD. None of the patients presented major postoperative complications or required re-intervention.

Conclusion

The management of IPN has shifted away from ON, which was associated with high morbidity, towards less invasive techniques. MIPs should be used initially as the surgical treatment of choice in most cases. When this is not feasible, or when the MIP is not successful, ON should be implemented.
  相似文献   
76.
77.
We recently reported the positional cloning of a homeobox gene involved in the pathogenesis of Rieger syndrome, RIEG1 , and its mouse homolog, Rieg1 . Rieg1 (also independently described as Pitx2) is highly homologous to the Ptx1/Potx gene product, suggesting that there may be additional members of this novel Pitx family. The Pitx genes play an important role in eye, tooth, pituitary and umbilical region development as evidenced by Rieger syndrome and iris hypoplasia phenotypes, resulting from mutations in the RIEG1 gene and by expression studies. In order to characterize further the Pitx gene family we searched mouse cDNA libraries to identify additional members. A new gene was isolated which encodes a homeoprotein with strong homology to the other Pitx proteins and 97-100% identity in the homeodomain itself, suggesting that this is a third member of the family, Pitx3 . In whole mount in situ hybridization on mouse embryos ranging from 8.5 to 11.5 days post-coitum (d.p.c.), Pitx3 mRNA was seen only in the developing lens starting at day 11. Hybridization on cross- sections revealed strong signals in the lens vesicle in 11 d.p.c. embryos and throughout the lens, particularly in the anterior epithelium and equator region in 15 d.p.c. embryos. Pitx3 was mapped close to aphakia on mouse chromosome 19. The aphakia homozygous mouse is characterized by small eyes lacking a lens, which fail to develop beyond 11 d.p.c. These data make Pitx3 a strong candidate gene for the aphakia phenotype in the mouse and suggest a role for the human homolog in congenital lens malformations.   相似文献   
78.
In patients undergoing exercise thallium-201 myocardial scintigraphy, activity in the inferior wall on anterior images may appear diminished when the standard supine view is used, but normal when the view is acquired with the patient upright. To determine the clinical significance of this observation, the distribution of thallium-201 activity was semiquantitatively assessed in supine and upright anterior images obtained immediately after exercise in 93 patients (65 men, 28 women). The presence of inferior wall and coronary artery disease was established with coronary angiography or from documentation of previous myocardial infarction. Supine and upright images were compared with use of receiver operating characteristic curves. In male patients diagnostic accuracy for identification of both inferior wall and coronary artery disease was improved through the use of the upright anterior image. In women, there was no significant difference in reader performance with upright and supine images. Upright anterior images should be routinely obtained in men in order to reduce the frequency of false-positive identification of inferior wall defects.  相似文献   
79.
We caught, 2002-2003 in caves of Novosibirsk Region and Altai Territory, 52 bats (Myotis daubentoni, Myotis brandtii, Murina leucogaster, Plecotus auritus). Examinations of the animals' brain samples by fluorescence antibody microscopy and RT-PCR revealed lyssaviruses, genotype 1, which were close to strains provoking rabies in the local animals. According to the results, bats can be involved in keeping alive the rabies foci in Western Siberia, which must be taken into account in antiepizootic measures.  相似文献   
80.
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