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31.
Human herpesvirus 8 seroprevalence and evaluation of nonsexual transmission routes by detection of DNA in clinical specimens from human immunodeficiency virus-seronegative patients from central and southern Italy, with and without Kaposi's sarcoma 下载免费PDF全文
Cattani P Capuano M Cerimele F La Parola IL Santangelo R Masini C Cerimele D Fadda G 《Journal of clinical microbiology》1999,37(4):1150-1153
In order to investigate the seroprevalence of human herpesvirus 8 (HHV-8) infection in central and southern Italy, sera from human immunodeficiency virus (HIV)-seronegative subjects, with and without Kaposi's sarcoma (KS), were analyzed by immunofluorescence assay, using BC-3, a cell line latently infected with HHV-8. High titers of antibody against HHV-8 lytic and latent antigens were detected in all 50 KS patients studied, while in 50 HIV-seronegative subjects without KS, 32 (64%) were found positive for HHV-8 antibodies. Titers in the sera of these patients were lower than those for KS patients. This data suggests that HHV-8 infection is not restricted to KS patients and that the prevalence of HHV-8 infection in the general population may be correlated with differing rates of prevalence of KS in different parts of the world. In view of these findings, possible nonsexual transmission routes were evaluated. Nested PCR was used to test for the presence of HHV-8 DNA in saliva, urine, and tonsillar swabs from KS and non-KS patients. In KS patients, 14 out of 32 tonsillar swabs (43.7%), 11 out of 24 saliva samples (45.8%), and just 2 out of 24 urine samples (8.3%) tested positive for HHV-8 DNA. In the control group, on the contrary, none of the 20 saliva and 20 urine specimens was positive for HHV-8 DNA; only 1 out of 22 tonsillar swabs gave a positive result. This data supports the hypothesis that HHV-8 infects the general population in a latent form. The reactivation of viral infection may result in salivary shedding of HHV-8, contributing to viral spread by nonsexual transmission routes. 相似文献
32.
De Carolis E Posteraro B Florio AR Colonna B Prosseda G Bugli F Lorenzetti SR Fiscarelli E Inzitari R Iavarone F Castagnola M Fadda G Sanguinetti M 《International journal of medical microbiology : IJMM》2011,301(4):273-281
Stenotrophomonas maltophilia is a microorganism of environmental and clinical importance as well as a frequent airway colonizer of cystic fibrosis (CF) individuals. We combined 2-DE and MALDI-TOF MS to profile the protein expression in S. maltophilia K279a, a completely sequenced clinical isolate, grown at 37 °C with respect to the strain grown at 26 °C. Among the proteins up-regulated at 37 °C, we identified GroEL, a molecular chaperone that mainly assist the folding and unfolding of proteins under both normal and stress conditions. A 2.4-kb groESL mRNA was detected independently by Northern blot analyses with a groES- and a groEL-specific probe, indicating that S. maltophilia groES and groEL form an operon. Primer extension analysis of S. maltophilia groESL done in Escherichia coli showed that 2 promoters, Pσ(32) and Pσ(70), were utilized under the heat-shock and normal condition, respectively, whereas S. maltophilia groEL was shown to act as a heat-shock gene at 37 °C, 42 °C, and, to a lesser extent, at 50 °C by real-time RT-PCR analyses. Finally, immunoblot analyses revealed that S. maltophilia GroEL strongly reacted with sera from CF patients chronically infected by the microorganism, but did not with sera from CF patients with sporadic infection or uninfected. 相似文献
33.
Fadda G Muie A Rufini V Ardito G Revelli L Fiorino MC Capelli A 《Endocrine pathology》2000,11(4):373-377
Cystic lesions of the thyroid are common findings. Although many thyroid cysts are of benign, some cases of hemorrhagic degenerative
changes occur in neoplastic nodules, mostly follicular neoplasms and papillary carcinomas. The occurrence of hemorrhagic changes
in medullary carcinomas has never been documented with aspirative cytological and histological pictures to the best of our
knowledge. A case of medullary thyroid carcinoma with a large central hemorrhagic cyst is described, and the literature regarding
the pathogenesis of this regression and the occurrence of cystic neoplasms in the thyroid is reviewed. 相似文献
34.
R. A. Sinico N. Mezzina B. Trezzi GM. Ghiggeri A. Radice 《Clinical and experimental immunology》2016,183(2):157-165
Membranous nephropathy (MN), the leading cause of nephrotic syndrome in adults, is characterized by the deposition of subepithelial immune deposits that consist mainly of immunoglobulin (Ig)G and complement. Most of the cases are primary or idiopathic (iMN), while only approximately 25% of the cases are secondary to some known disease such as systemic lupus erythematosus, hepatitis B, drugs and malignancies. Most of our knowledge on the pathogenesis of iMN has relied upon old experimental models (i.e. Heymann nephritis) that have shown that immune deposits are formed in situ by the reaction of autoantibodies against the respective podocyte antigen. Recent findings indicate that podocyte proteins also act as an autoantigen in human iMN. The M‐type phospholipase A2 receptor (PLA2R) has been identified as the main target antigen, as it can be found in approximately 70% of iMN patients but only rarely in other glomerulonephritides. Podocytes damage in the experimental model of Heymann nephritis is complement‐mediated. In humans, the presence of complement within the subepithelial deposits is well established, but IgG4, which does not activate complement by classical or alternative pathways, represents the predominant subclass of IgG anti‐PLA2R. Some evidence suggests that IgG4 anti‐PLA2R autoantibodies can bind mannan‐binding lectin (MBL) and activate the lectin complement pathway. A genetic background for iMN has been demonstrated by genome‐wide association studies that have shown highly significant associations of the PLA2R1 and the human leucocyte antigen (HLA)‐DQA1 loci with iMN. In addition to their diagnostic value, anti‐PLA2R antibodies may be useful to monitor disease activity and predict response to treatment. 相似文献
35.
Janneke AL van Kempen Henk J Schers Anne Jacobs Sytse U Zuidema Franca Ruikes Sarah HM Robben René JF Melis Marcel GM Olde Rikkert 《The British journal of general practice》2013,63(608):e225-e231
Background
Primary care is increasingly interested in the identification of frailty, as it selects the target population for integrated care. However, instruments for the identification of frailty specifically validated for use in primary care are scarce. This study developed the Easycare Two-step Older persons Screening (Easycare-TOS), which provides a valid, efficient, and pragmatic screening procedure to identify frail older people.Aim
This paper aims to describe the development of the Easycare-TOS and the data from the pilot studies.Design and setting
Observational pilot study in seven academic GP practices in and around Nijmegen, The Netherlands.Method
The Easycare-TOS was developed in a cyclic process with the input of stakeholders. In every cycle, the requirements were first defined, then translated into a prototype that was tested in a pilot study. The Easycare-TOS makes optimal use of prior knowledge of the GP, and the professionals’ appraisal is decisive in the frailty decision, instead of a cut-off score. Further, it considers aspects of frailty, as well as aspects of the care context of the patient.Results
The pilot data have shown that after step 1, two-thirds of the patients do not need further assessment, because they are judged as not frail, based on prior knowledge of the GP. The overall prevalence of frailty in this pilot study is 24%. Most professionals who participated in the pilot studies considered the time investment acceptable and the method to be of added value.Conclusion
The Easycare-TOS instrument meets the predefined efficiency, flexibility, and acceptability requirements for use as an identification instrument for frailty in primary care. 相似文献36.
Detection and typing of herpes simplex viruses by using recombinant immunoglobulin fragments produced in bacteria. 下载免费PDF全文
P Cattani G M Rossolini S Cresti R Santangelo D R Burton R A Williamson P P Sanna G Fadda 《Journal of clinical microbiology》1997,35(6):1504-1509
Thirty-seven bacterial clones producing human recombinant monoclonal antibody Fab fragments (rFabs) reactive to herpes simplex virus (HSV) antigens were selected from a human combinatorial antibody library constructed in a phage-display vector by a panning procedure against an HSV lysate. Thirty-four of the HSV-specific rFabs were able to specifically recognize HSV-infected cells in indirect immunofluorescence (IF) assays; of these, 25 recognized cells infected by either HSV type 1 (HSV-1) or HSV-2, while 9 recognized only HSV-1-infected cells. One HSV type-common rFab (rFab H37) and one HSV-1-specific rFab (rFab H85) were further evaluated as reagents for viral detection and typing by IF staining in 134 HSV-positive (72 HSV-1 and 62 HSV-2) viral cultures from clinical specimens. The results obtained with these two rFabs were fully consistent with those obtained with a commercial preparation of fluorescein-labeled anti-HSV type-specific murine monoclonal antibodies. The detection sensitivity with the type-common rFab in indirect IF assays was higher overall than that provided by the type-specific murine monoclonal antibodies. Preparations of rFabs suitable for IF staining can be easily and inexpensively obtained in a clinical microbiology laboratory from Escherichia coli cultures. Similar HSV-specific rFabs, therefore, could be advantageous for in vitro diagnostic purposes. 相似文献
37.
Evaluation of a nonradiometric system (BACTEC 9000 MB) for detection of mycobacteria in human clinical samples. 总被引:2,自引:4,他引:2 下载免费PDF全文
S Zanetti F Ardito L Sechi M Sanguinetti P Molicotti G Delogu M P Pinna A Nacci G Fadda 《Journal of clinical microbiology》1997,35(8):2072-2075
This study was carried out to evaluate the rate of recovery and time required for detection of mycobacteria from pulmonary and extrapulmonary human clinical samples, by using a fluorescence-quenching-based oxygen sensor (BACTEC 9000 MB; Becton Dickinson Microbiology Systems, Sparks, Md.). The results were compared with those obtained by microscopy, conventional culture in Lowenstein-Jensen (LJ) medium, and a BACTEC radiometric system (BACTEC 460 TB; Becton Dickinson). Of the 779 clinical samples processed, 364 from pulmonary sites and 415 from extrapulmonary sites, 62 (7.9%) were positive for mycobacterial isolates; of the positive samples, 59 (95.1%) were detected with the fluorescent BACTEC 9000 MB system, 57 (91.9%) were detected with the radiometric system (BACTEC 460 TB), and 43 (69.3%) were detected with LJ conventional culture. The mean times to detection of all mycobacteria with BACTEC 9000 MB and BACTEC 460 TB were similar (10.3 and 10.0 days, respectively). The results obtained indicate that the nonradiometric BACTEC (BACTEC 9000 MB) system is as efficient as Bactec 460 TB and significantly more efficient than LJ for the rapid recovery of mycobacteria from both pulmonary and extrapulmonary clinical specimens. Though the BACTEC 9000 MB system is recommended for respiratory specimens, we demonstrated that it can be successfully used also for recovery of mycobacteria from clinical specimens from various extrapulmonary sites. 相似文献
38.
Early transvaginal ultrasound following an accurately dated pregnancy: the importance of finding a yolk sac or fetal heart motion 总被引:1,自引:2,他引:1
Deaton JL; Honore GM; Huffman CS; Bauguess P 《Human reproduction (Oxford, England)》1997,12(12):2820-2823
Our goals were to determine the prognostic value of a yolk sac or fetal
heart motion seen during an early accurately dated transvaginal ultrasound
(TVU). We reviewed 225 consecutive pregnancies for fetal heart motion data.
Furthermore, 63 pregnancies following in-vitro fertilization were reviewed
for yolk sac information. The TVU was performed between 5 and 6 weeks
following presumed conception (heart motion data) and between 22 and 32
days following in-vitro fertilization (yolk sac data). Pregnancies were
followed until an ongoing pregnancy or spontaneous abortion was documented.
The presence of a yolk sac between 22 and 32 days from fertilization was
associated with the development of fetal heart motion in 94% of cases. The
absence of the yolk sac by 32 days after fertilization was always
associated with a poor outcome. In women < 36 years of age, the presence
of fetal heart motion was associated with a spontaneous abortion in only
4.5% of the cases. However, the incidence of spontaneous abortion following
fetal heart motion increased to 10% in women 36-39 years and 29% in women
> or = 40 years of age. The presence of heart motion should not be
considered a reassuring sign in the older woman. These data have
implications regarding early embryology and the counselling of infertility
patients.
相似文献
39.
Warnes GM; Payne D; Jeffrey R; Hourigan L; Kirby C; Kerin J; Matthews C 《Human reproduction (Oxford, England)》1997,12(7):1525-1530
Over a 26 month period 17% of couples having treatment in our clinical
programmes selected a commercially available protein (normal serum albumin,
NSA) prepared from pooled human sera instead of using their own serum as a
supplement for their embryo culture media. In a retrospective analysis of
>2000 gonadotrophin-stimulated cycles and 1000 cycles where
frozen/thawed embryos were transferred, fertilization, embryo quality and
pregnancy rates following in-vitro fertilization (IVF), gamete
intra-Fallopian transfer (GIFT) or intracytoplasmic sperm injection (ICSI)
were unaffected by the type of protein used to supplement the culture
medium. When embryos were thawed in medium containing NSA, both pregnancy
(PR) and implantation rates (IR) were significantly lower (P <0.05) than
if the medium was supplemented with serum (PR 8.3% and 17.5%; IR 4.6% and
10.5%). Inclusion of NSA before freezing reduced the IR of thawed embryos.
To further test this observation all cycles where embryos were cultured and
frozen in medium containing NSA (173 cycles) were matched to cycles where
serum was used and the outcome was compared. At the end of 1995 just over
half of the embryos in both groups had been thawed. No statistical
difference was noted in the pregnancy rates (NSA, 5.6% versus serum, 11.3%)
but the IR per embryo was significantly lower when embryos were cultured
and frozen in medium supplemented with NSA (2.2%) than when serum was used
as the supplement (6.6%).
相似文献