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41.
Bacillus anthracis, the etiologic agent of anthrax, has been widely described as a genetically monomorphic species. We used both multiple-locus variable-number tandem-repeat analysis (MLVA) and pagA gene sequencing to determine the genetic diversity of a historical collection of B. anthracis isolates collected from the 1950s to the 1980s from various geographic locations and sources. We sequenced the pagA gene of 124 diverse B. anthracis isolates and found all previously identified B. anthracis pagA types except type 4. Sixty-three of the 124 B. anthracis strains were identified as pagA type 6, while 44 were pagA type 5, 12 were pagA type 1, and individual isolates were identified for types 2 and 3, respectively. Two new pagA genotypes were discovered in three environmental isolates within the historical collection. Two isolates had the same new genotype, and an additional isolate produced a second new genotype. MLVA detected 22 previously described genotypes in the historical collection. In addition, 33 new MLVA genotypes were found. For 11 isolates, an MLVA genotype could not be assigned because one or more alleles did not amplify. While only two additional B. anthracis pagA types were identified, in two instances, the use of pagA sequencing discriminated isolates with the same MLVA genotype. MLVA revealed that 39 of the 124 isolates were previously undocumented genotypes and that 1 isolate was found to be in the C cluster when it was subtyped by MLVA.  相似文献   
42.
Germline mutations of c-met oncogene at 7q31 have been detected in patients with hereditary papillary renal cell carcinoma. In addition, c-met mutations were shown to play a role in 13% of patients with papillary renal cell carcinoma and no family history of renal tumors. The histopathology of papillary renal cell carcinoma with c-met mutations has not been previously described. We analyzed the histopathology of 103 bilateral archival papillary renal cell carcinomas and 4 metastases in 29 patients from 6 hereditary papillary renal cell carcinoma families with germline c-met mutations and 6 papillary renal cell carcinomas with c-met mutations from 5 patients with no family history of renal tumors. Twenty-five sporadic renal tumors with prominent papillary architecture and without somatic c-met mutations were evaluated for comparison. All papillary renal cell carcinomas with c-met mutations were 75 to 100% papillary/tubulopapillary in architecture and showed chromophil basophilic, papillary renal cell carcinoma type 1 histology. Fuhrman nuclear grade 1-2 was seen in tumors from 23 patients, and nuclear grade 3 was observed focally in 8 patients. Seventeen patients had multiple papillary adenomas and microscopic papillary lesions in the surrounding renal parenchyma. Clear cells with intracytoplasmic lipid and glycogen were focally present in tumors of 94% papillary renal cell carcinoma patients. Clear cells of papillary renal cell carcinoma had small basophilic nuclei, and clear cell areas lacked a fine vascular network characteristic of conventional (clear) cell renal cell carcinoma. We conclude that papillary renal cell carcinoma patients with c-met mutations develop multiple, bilateral, papillary macroscopic and microscopic renal lesions. Renal tumors with c-met genotype show a distinctive papillary renal cell carcinoma type 1 phenotype and are genetically and histologically different from renal tumors seen in other hereditary renal syndromes and most sporadic renal tumors with papillary architecture. Although all hereditary and sporadic papillary renal cell carcinomas with c-met mutations share papillary renal cell carcinoma type 1 histology, not all type 1 sporadic papillary renal cell carcinomas harbor c-met mutations.  相似文献   
43.
We studied evidence of Bartonella henselae and Bartonella clarridgeiae infection in 54 cats living in Jakarta, Indonesia. By using an indirect immunofluorescence assay, we found immunoglobulin G antibody to B. henselae in 40 of 74 cats (54%). The blood of 14 feral cats was cultured on rabbit blood agar plates for 28 days. Bartonella-like colonies were identified as B. henselae or B. clarridgeiae by using restriction fragment length polymorphism analysis and direct sequencing of the PCR amplicons. Of the cats sampled in the study, 6 of 14 (43%; all feral) were culture positive for B. henselae; 3 of 14 (21%; 2 feral and 1 pet) culture positive for B. clarridgeiae. This is the first report that documents B. henselae and B. clarridgeiae infections in Indonesian cats.  相似文献   
44.
45.

Background

Older people living in care homes often have limited life expectancy. Practitioners and policymakers are increasingly questioning the appropriateness of many acute hospital admissions and the quality of end-of-life care provided in care homes.

Aim

To describe care home residents’ trajectories to death and care provision in their final weeks of life.

Design and setting

Prospective study of residents in six residential care homes in three sociodemographically varied English localities: Hertfordshire, Essex, and Cambridgeshire.

Method

Case note reviews and interviews with residents, care home staff, and healthcare professionals.

Results

Twenty-three out of 121 recruited residents died during the study period. Four trajectories to death were identified: ‘anticipated dying’ with an identifiable end-of-life care period and death in the care home (n = 9); ‘unexpected dying’ with death in the care home that was not anticipated and often sudden (n = 3); ‘uncertain dying’ with a period of diagnostic uncertainty or difficult symptom management leading to hospital admission and inpatient death (n = 7); and ‘unpredictable dying’ with an unexpected event leading to hospital admission and inpatient death (n = 4). End-of-life care tools were rarely used. Most residents who had had one or more acute hospital admission were still alive at the end of the study.

Conclusion

For some care home residents there was an identifiable period when they were approaching the end-of-life and planned care was put in place. For others, death came unexpectedly or during a period of considerable uncertainty, with care largely unplanned and reactive to events.  相似文献   
46.

Objectives

To determine whether abnormalities of lung volume and/or airway function were associated with wheeze at follow‐up in infants born very prematurely and to identify risk factors for wheeze.

Design

Lung function data obtained at 1 year of age were collated from two cohorts of infants recruited into the UKOS and an RSV study, respectively.

Setting

Infant pulmonary function laboratory.

Patients

111 infants (mean gestational age 26.3 (SD 1.6) weeks).

Interventions

Lung function measurements at 1 year of age corrected for gestational age at birth. Diary cards and respiratory questionnaires were completed to document wheeze.

Main outcome measures

Functional residual capacity (FRCpleth and FRCHe), airways resistance (Raw), FRCHe:FRCpleth and tidal breathing parameters (TPTEF:TE).

Results

The 60 infants who wheezed at follow‐up had significantly lower mean FRCHe, FRCHe:FRCpleth and TPTEF:TE, but higher mean Raw than the 51 without wheeze. Regression analysis demonstrated that gestational age, length at assessment, family history of atopy and a low FRCHe:FRCpleth were significantly associated with wheeze.

Conclusions

Wheeze at follow‐up in very prematurely born infants is associated with gas trapping, suggesting abnormalities of the small airways.  相似文献   
47.
BACKGROUND: The clinical and prognostic significance of "inadequate" cervical smear is unknown, even though women with repeated inadequate smears are referred for colposcopy in the National Health Service (NHS) Cervical Screening Programme. Aim: To follow up a cohort of women with inadequate cervical smears over the following five years to examine outcomes, including detection of high grade cervical intraepithelial neoplasia (CIN). METHODS: The study comprised 1972 women with an inadequate cervical smear reported at Walsall Hospitals NHS Trust between 1 April 1995 and 31 March 1996. Results of cervical smears and biopsies taken over the following five years were reviewed to confirm the outcome. FINDINGS: Within five years, 2.2% of women with an inadequate cervical smear developed histologically confirmed high grade CIN, which was higher than the 1.3% seen among all women with cervical smear tests reported at the same laboratory over the same period, although the difference was not significant at the 95% level of confidence. Where inadequacy resulted from or was contributed to by "polymorphs obscuring", the risk of subsequent development/detection of high grade CIN was 2.6%. CONCLUSIONS: Women with inadequate cervical smears had an increased risk of detection of high grade CIN in the following five years compared with "all women". This increased risk was not significant, although if a larger number of women had been studied significance may have been reached, so that further studies are needed. The increased risk appeared to be at least partially dependent on the reason for inadequacy.  相似文献   
48.
We report the use of spectral karyotyping (SKY) and comparative genomic hybridization (CGH) to describe the numerous genomic imbalances characteristic of stage IV clear cell renal cell carcinoma (CCRCC). SKY and CGH were performed on 10 cell lines established from nephrectomy specimens, and CGH on uncultured material from five of the primary renal tumors. The mutational status of VHL (3p25) and MET (7q31), genes implicated in renal carcinogenesis, were determined for each case. Each case showed marked aneuploidy, with an average number of copy alterations of 14.6 (+/-2.7) in the primary tumors and 19.3 (+/-4.6) in the cell lines. Both whole-chromosome and chromosome-segment imbalances were noted by CGH: consistent losses or gains included +5q23-->ter (100%), -3p14-->ter (80%), and +7 (70%). All VHL mutations and 83% of the genomic imbalances found in the primary tumors were also found in the cell lines derived from them. SKY showed many complex structural rearrangements that were undetected by conventional banding analysis in these solid tumors. All cases with VHL inactivation had 3p loss and 5q gain related primarily to unbalanced translocations between 3p and 5q. In contrast, gains of chromosome 7 resulted primarily from whole-chromosome gains and were not associated with mutations of MET. SKY and CGH demonstrated that genomic imbalances in advanced RCC were the result of either segregation errors [i.e., whole chromosomal gains and losses (7.8/case)] or chromosomal rearrangements (10.7/case), of which the majority were unbalanced translocations.  相似文献   
49.
Oral inoculation of 5-day-old gnotobiotic pigs with Salmonella enterica serovar Typhimurium strain F98 resulted in severe enteritis and invasive disease. Preinoculation 24 h earlier with an avirulent mutant of Salmonella enterica serovar Infantis (1326/28) completely prevented disease for up to 14 days (when the experiment was terminated). S. enterica serovar Infantis colonized the alimentary tract well, with high bacterial counts in the intestinal lumen but with almost no invasion into the tissues. Unprotected pigs had high S. enterica serovar Typhimurium counts in the intestines, blood, and major nonintestinal organs. Recovery of this strain from the blood and major organs in S. enterica serovar Infantis-protected pigs was substantially reduced despite the fact that intestinal counts were also very high. Protection against disease thus did not involve a colonization exclusion phenomenon. Significant (P < 0.05) infiltration of monocytes/macrophages was observed in the submucosal regions of the intestines of both S. enterica serovar Infantis-protected S. enterica serovar Typhimurium-challenged pigs and unprotected S. enterica serovar Typhimurium-challenged pigs. However, only polymorphonuclear neutrophils (PMNs) were observed throughout the villus, where significant (P < 0.05) numbers infiltrated the lamina propria and the subnuclear and supranuclear regions of the epithelia, indicating that PMN induction and positioning following S. enterica serovar Infantis inoculation was consistent with rapid protection against the challenge strain. Similarly, in vitro experiments using a human fetal intestinal epithelial cell line (INT 407) demonstrated that, although significantly (P < 0.05) fewer S. enterica serovar Infantis than S. enterica serovar Typhimurium organisms invaded the monolayers, S. enterica serovar Infantis induced an NF-kappaB response and significantly (P < 0.05) raised interleukin 8 levels and transmigration of porcine PMN. The results of this study suggest that attenuated Salmonella strains can protect the immature intestine against clinical salmonellosis by PMN induction. They also demonstrate that PMN induction is not necessarily associated with clinical symptoms and/or intestinal pathology.  相似文献   
50.
Von Hlppel—Lindau (VHL) disease is a dominantly Inheritedfamillal cancer syndrome In which affected individuals havea greatly increased predisposition to the development of haemangloblastomasof the central nervous system and retina, renal cell carcinomaand phaeochromocytoma. The VHL gene has been mapped to chromosome3p25 -p26 by genetic linkage studies and we have previouslydemonstrated that the VHL gene is tightly linked to the D3S601locus (Zmax = 18.86 at  相似文献   
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