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31.
Orthopoxvirus DNA: strain differentiation by electrophoresis of restriction endonuclease fragmented virion DNA. 总被引:6,自引:0,他引:6
Procedures were developed for purifying intact intracytoplasmic poxvirus particles from infected cells and for isolating DNA from virions by equilibrium centrifugation in sodium diatrizoate density gradients. The buoyant density of twelve closely related orthopoxviruses purified in these gradients was determined to be 1.25 g/ml, and that of the isolated virion DNAs was 1.1 g/ml. Virion DNA from each of the 12 selected prototype and wild-type viruses was cleaved with three separate site-specific restriction endonucleases, Hin d III, Sal I, and Bam HI, and the fragments (molecular weights 0.5 × 106 to 20 × 106) were separated by agarose gel electrophoresis. Characteristic DNA fragment migration patterns observed in the gels permitted classification of the viruses. By comparing profiles of Hin d III cleaved DNAs we were able to group the viruses into 4 species: cowpox, vaccinia, monkeypox (2 isolates), and variola (8 isolates). Viruses from variola major infection could be differentiated from viruses from variola minor infection. Isolates within species (strains) were also differentiated, mainly by comparing the gel electrophoresis profiles of Sal I digested DNA from the viruses. 相似文献
32.
Baldi A Santini M Mellone P Esposito V Groeger AM Caputi M Baldi F 《Journal of clinical pathology》2004,57(9):993-994
Hibernomas are rare benign tumours that arise most often in adults from the remnants of fetal brown adipose tissue. They usually affect muscle and subcutaneous tissue and are asymptomatic and slow growing. The distribution of this tumour follows the sites of persistence of brown fat. Out of more then 100 cases described in the word literature only three hybernomas were mediastinal. A recent clinicopathological study of 170 cases from the Armed Forces Institute of Pathology confirmed the exceptionality of the intrathoracic location. This report describes a very rare case of mediastinal hibernoma in a young man. 相似文献
33.
Dpc4 is expressed in virtually all primary and metastatic pancreatic endocrine carcinomas 总被引:2,自引:0,他引:2
Scarpa A Orlandini S Moore PS Lemoine NR Beghelli S Baron A Falconi M Zamboni G 《Virchows Archiv : an international journal of pathology》2002,440(2):155-159
DPC4/Smad4 is inactivated in about 50% of pancreatic ductal cancers. It has been recently reported that this gene is also inactivated in neoplasms arising from pancreatic islet cells, a phenomenon suggested to be related to similar progressions of malignancy found in common ductal cancers. To evaluate this possibility, we analysed 20 metastases of pancreatic endocrine carcinomas and their corresponding primary lesion for inactivation of DPC4 using immunohistochemical staining. In fact, immunohistochemical labelling has been shown to correlate with DPC4 gene status with high sensitivity and specificity. The cancers included 18 nonfunctioning tumours, one gastrinoma and one ViPoma all with liver, nodal and/or adrenal metastases. Seventeen were well-differentiated and three poorly differentiated endocrine carcinomas. Dpc4 expression was absent in only one primary well-differentiated endocrine cancer and its liver metastasis, while all the remaining 19 primary tumours and their metastases stained positive for the protein. All positively staining cases showed diffuse cytoplasmic and nuclear staining in virtually all neoplastic cells. Our data suggest that DPC4 is only rarely involved in pancreatic endocrine tumourigenesis and give further weight to the hypothesis that tumours arising from pancreatic exocrine and endocrine epithelia are genetically distinct. 相似文献
34.
Clinical,immunological, and molecular analysis in a large cohort of patients with X-linked agammaglobulinemia: an Italian multicenter study 总被引:5,自引:0,他引:5
Plebani A Soresina A Rondelli R Amato GM Azzari C Cardinale F Cazzola G Consolini R De Mattia D Dell'Erba G Duse M Fiorini M Martino S Martire B Masi M Monafo V Moschese V Notarangelo LD Orlandi P Panei P Pession A Pietrogrande MC Pignata C Quinti I Ragno V Rossi P Sciotto A Stabile A;Italian Pediatric Group for XLA-AIEOP 《Clinical immunology (Orlando, Fla.)》2002,104(3):221-230
A questionnaire-based retrospective clinical and immunological survey was conducted in 73 males with a definite diagnosis of X-linked agammaglobulinemia based on BTK sequence analysis. Forty-four were sporadic and 29 familial cases. At December 2000, the patients' ages ranged from 2 to 33 years; mean age at diagnosis and mean duration of follow-up were 3.5 and 10 years respectively. After the mid-1980s all but 2 were on intravenous immunoglobulin (IVIG) substitution therapy, with residual IgG >500 mg/dl in 94% of the patients at the time of enrollment. Respiratory infections were the most frequent manifestation both prior to diagnosis and over follow-up. Chronic lung disease (CLD) was present in 24 patients, in 15 already at diagnosis and in 9 more by 2000. The cumulative risk to present at diagnosis with CLD increased from 0.17 to 0.40 and 0.78 when the diagnosis was made at the ages of 5, 10, and 15 years respectively. For the 9 patients who developed CLD during follow-up, the duration of follow-up, rather than age at diagnosis; previous administration of intramuscular immunoglobulin; and residual IgG levels had a significant effect on the development of CLD. Chronic sinusitis was present in 35 patients (48%), in 15 already at diagnosis and in 20 by 2000. Sistemic infections such as sepsis and meningitis/meningoencephalitis decreased over follow-up, probably due to optimal protection provided by high circulating IgG levels reached with IVIG. 相似文献
35.
Reliability of a single urine culture in establishing diagnosis of asymptomatic bacteriuria in adult males. 下载免费PDF全文
Fifty-nine asymptomatic men without catheters of ileal-loop bladders, who were attending a urology clinic and were incidentally discovered to have 100,000 or more Enterobacteriaceae per ml ("significant bacteriuria") in a clean voided urine sample, were prospectively evaluated. To identify these 59 patients, 5,876 urine samples, collected exclusively from men, had been subjected to quantitation and identification. A repeat urine culture performed on these patients invariably confirmed the results of the initial culture. The reproducibility of a single urine culture containing significant bacteriuria occurred independently of the tissue source of infection, as determined by the antibody-coated-bacteria immunofluorescence test. We conclude that a single urine culture obtained from a cooperative man can establish the diagnosis of asymptomatic bacteriuria. 相似文献
36.
The aim of this study was to define the effects of diltiazem, a calcium antagonist drug used in cardiology and in clinical transplantation, on the differentiation and maturation of human dendritic cells (DC). Herein, we demonstrate that diltiazem, in association with granulocyte macrophage-colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4), induces monocytes to differentiate into cells with many of the characteristic of DC. However, diltiazem-induced DC express high levels of mannose receptor and Fc gamma RII and, consequently, manifest a higher endocytic activity compared with GM-CSF+IL-4-induced DC. Importantly, diltiazem-induced DCs have an impaired responsiveness to lipopolysaccharide and CD40 ligand because they produce decreased levels of IL-12 and reveal a reduced ability to stimulate alloreactive T-cell responses as well as in inducing interferon-gamma producing Th1 cells. These effects may contribute to a decreased DC-dependent T-cell activation and may help to explain the immunoregulatory function of diltiazem and its effectiveness in preventing transplant rejection. 相似文献
37.
Ambient air and its potential effects on conception in vitro 总被引:5,自引:1,他引:5
Cohen J; Gilligan A; Esposito W; Schimmel T; Dale B 《Human reproduction (Oxford, England)》1997,12(8):1742-1749
Incidences of chemical air contamination (CAC) are common in assisted
reproductive technology, but not reported in peer review format. Justified
fear of car and industrial emissions clearly exists among reproductive
specialists, but standards for air contents and gaseous emission limits
have not been reported. Here, we describe air sampling methods and assay
systems which can be applied to any laboratory or laboratory item. It was
found that unfiltered outside air may be cleaner than high efficiency
particulate air filtration (HEPA) filtered laboratory air or air obtained
from incubators, due to accumulation of volatile organic compounds derived
from adjacent spaces or specific laboratory products such as compressed
CO2, sterile Petri dishes and other materials or devices known to release
gaseous emissions. Specific groups of products such as anaesthetic gases,
refrigerants, cleaning agents, hydrocarbons and aromatic compounds such as
benzene and toluene are described. The latter were shown to accumulate
specifically in incubators. Isopropyl alcohol was the most dominant product
found, though it was not used by the laboratory staff. Concentrations of
this agent were low in incubator air, indicating that it was probably
absorbed by the water in the pan or by culture medium. Measures to counter
CAC are proposed, including the use of activated carbon filters and
oxidizing material placed in the central air handling systems, in separate
free-standing units or even inside the incubators.
相似文献
38.
Francesca Fernandez Teresa Esposito Rod A Lea Natalie J Colson Alfredo Ciccodicola Fernando Gianfrancesco Lyn R Griffiths 《BMC medical genetics》2008,9(1):109
Background
Migraine is a neurological disorder characterized by recurrent attacks of severe headache, affecting around 12% of Caucasian populations. It is well known that migraine has a strong genetic component, although the number and type of genes involved is still unclear. Prior linkage studies have reported mapping of a migraine gene to chromosome Xq 24–28, a region containing a cluster of genes for GABA A receptors (GABRE, GABRA3, GABRQ), which are potential candidate genes for migraine. The GABA neurotransmitter has been implicated in migraine pathophysiology previously; however its exact role has not yet been established, although GABA receptors agonists have been the target of therapeutic developments. The aim of the present research is to investigate the role of the potential candidate genes reported on chromosome Xq 24–28 region in migraine susceptibility. In this study, we have focused on the subunit GABA A receptors type ε (GABRE) and type θ (GABRQ) genes and their involvement in migraine. 相似文献39.
Monica Ruotolo Mario Gagliardi Carolina Ciacci Fabiana Zingone Corina de Santis Ciacci Antonella Santonicola Giovanna DArcangelo Monica Siniscalchi 《Nutrients》2021,13(6)
Background: Coronavirus disease 2019 (COVID-19) causes not only severe illness but also detrimental effects associated with the lockdown measures. The present study aimed to evaluate reported lifestyle changes in a cohort of adults in Italy, including physical exercise, food choices, and psychological wellbeing, after two months of lockdown. Methods: A web survey on social media (Facebook and LinkedIn) of 32 multiple-choice questions aiming to evaluate the impact of the national COVID-19 lockdown in a sample of Italian adults. Results: We received 1378 complete responses (women 68.3%, mean age 39.5 ± 12.5 years). The percentage of participants reporting regular exercise decreased during lockdown (52 vs. 56.5%). The vast majority of people continued to consume the three traditional meals per day, but the consumption of meat, fish, and eggs significantly decreased. Women reported more frequent anxiety, sadness, fear, and feelings of insecurity than men. The factors predicting the worst outcome during the lockdown were being a woman, low education and income, gastrointestinal diseases. Conclusion: The lockdown has had a limited impact on food choices and physical exercise in Italian adults of our series, since most of them made an effort to improve their lifestyle. However, women with gastrointestinal diseases reported more frequent negative feelings and poor adaptation to the lockdown. 相似文献
40.
Biasi Giovanni; Panozzo Marina; Pertile Paolo; Mezzalira Silvio; Facchinetti Antonella 《International immunology》1994,6(7):983-989
We observed that peripheral T cells activated in vivo or invitro by superantigens are susceptible to cell death when theirantigen receptor is cross-linked with the appropriate anti-ßTCR mAb. TCR ligation by mAbs specifically drove the T cellclonal deletion in both CD4+ and CD8+ cell subsets. An IL-2/1L-2Rinteraction seems to be a critical step In predisposing superantigenactivated cells to death; In fact, in vivo IL-2R bockade reversedT cell deletion In superantlgen plus anti-ß TCR mAbtreated mice. TCR ligatlon by mAbs also produced cell deathof the relevant targets in in vitro IL-2 activated T cells.Surprisingly, no T cell deletion was demonstrable in IL-2 activatedcells following staphylococcal enterotoxin B - TCR Interaction,ruling out the possibility that superantigen in Itself can inducecell death. Thus, while superantigen activation opens the celldeath program, a subsequent TCR-antigen (self) Interaction appearsnecessary to produce clonal deletion in mature T lymphocytes. 相似文献