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1.
Oral ganciclovir prophylaxis decreases the incidence of cytomegalovirus (CMV) disease among persons infected with the human immunodeficiency virus (HIV), but universal prophylaxis is not cost-effective. We evaluated urine and peripheral blood mononuclear cell cultures, a qualitative and quantitative antigenemia assay, and a commercially available CMV DNA hybridization assay for their ability to predict CMV disease in 138 HIV-infected patients. During a median follow-up of 10 months, 23 patients (17%) developed CMV disease. The sensitivity, specificity, positive predictive value, negative predictive value, and mean lead times for the antigenemia assay (with use of a threshold of 8 positive cells per 10(5) peripheral blood mononuclear cells as a positive) were 74%, 91%, 63%, 95%, and 95 days, respectively. Corresponding figures for the DNA hybridization assay were 91%, 64%, 34%, 97%, and 152 days. These assays can identify patients at increased risk of CMV disease and should allow a strategy of preemptive therapy to be tested.  相似文献   

2.
The retinal pigment epithelium (RPE) can undergo reactive hyperplasia and metaplasia following a variety of ocular insults. However, true neoplasms of the RPE are rare. We report a case of a papillary adenocarcinoma of the RPE arising in the blind staphylomatous right eye of a 79-year-old woman with a long history of bilateral posterior staphylomas who was seen with increasing pain and exophthalmos of the right eye. Findings from ultrasonography and computed tomography demonstrated linear calcification consistent with osseous metaplasia of the RPE. Progression of the exophthalmos and worsening exposure keratitis led to enucleation of the eye. Gross pathology showed a 79-mm-long globe. Histopathologic findings revealed a largely amelanotic papillary adenocarcinoma arising from the RPE. Positive immunoreactivity for cytokeratin supported the epithelial origin of the tumor. Adenocarcinoma of the RPE is rare but may develop in a blind eye.  相似文献   

3.
We conducted a comparative evaluation of the Chlamydiazyme (Abbott Laboratories), PACE 2 (Gen-Probe), and AMP-CT (Gen-Probe) assays for the detection of Chlamydia trachomatis in endocervical samples. Specimens from 787 females were included in the study. The sensitivities of the PACE 2 and Chlamydiazyme assays in comparison to the results of the AMP-CT assay were 79.3 and 63.4%, respectively. The specificities of the Chlamydiazyme and PACE 2 assays were 100%. All of the positive specimens detected in this study were positive by the AMP-CT assay. On the basis of the final results of the comparison, the prevalence of C. trachomatis in the population was 10.4%. Retesting of specimens whose results were in the intermediate zone by the PACE 2 assay by a probe competition assay identified some additional true-positive specimens. Amplification assay testing of such specimens did not significantly increase the yield. The majority of specimens which tested positive by the AMP-CT assay only were not in the intermediate zone by the PACE 2 assay. We were unable to identify demographic or clinical factors which could predict those individuals who tested positive by amplified tests but not by nonamplified tests. The Gen-Probe PACE 2 assay proved to be superior to the Chlamydiazyme assay for the screening and diagnosis of C. trachomatis infections in female endocervical specimens.  相似文献   

4.
BACKGROUND: Epidemiologic studies have demonstrated strong and consistent associations between the detection of human papillomavirus (HPV) type 16 DNA and the risk of cervical intraepithelial neoplasia (CIN) and cervical cancer. However, HPV16 is also the most common type of HPV in the normal population, and only a minority of women with HPV16 infection develop cervical cancer. Studies of genomic heterogeneity in HPV16 have demonstrated the presence of multiple variant forms in all human populations examined to date. It is conceivable that the natural variants of HPV16 in a given population may not have the same biologic behavior. PURPOSE: This study was designed to determine the association between natural variants of HPV16 and the risk of biopsy-confirmed CIN 2 or 3, the most important precancerous lesions of the uterine cervix. METHODS: Prospective studies were conducted among 1) women attending a university and 2) women presenting to a sexually transmitted disease clinic. Subjects were eligible for inclusion in this investigation if the initial cytologic findings did not reveal CIN 2-3 and HPV16 DNA was detected by means of a polymerase chain reaction (PCR)-based method in one or more cervical or vulvovaginal samples. Eligible subjects were followed every 4 months with cervical Pap smears and colposcopic examinations. Women were referred for biopsy if cytology or colposcopy suggested CIN 2-3. Two groups of HPV16 variants, prototype-like and nonprototype-like, were determined by means of single-strand conformation polymorphism (SSCP) analysis of PCR products from the noncoding region of the viral genome. Representative SSCP patterns from HPV16 variants were further characterized by direct DNA sequencing of the PCR products. Relative risks (RRs) and 95% confidence intervals (CIs) were calculated by Cox regression analysis. RESULTS: Prototype-like variants accounted for 79% of the HPV16 detected in university students and 86% of the virus detected in patients presenting to the sexually transmitted disease clinic. CIN 2-3 was confirmed by biopsy in nine of 57 HPV16-positive women attending the university and in 10 of 66 HPV16-positive women presenting to the sexually transmitted disease clinic. Among university students, those with HPV16 nonprototype-like variants were 6.5 (95% CI = 1.6-27.2) times more likely to develop CIN 2-3 than those with prototype-like variants. A similar association was observed among women presenting to the sexually transmitted disease clinic (RR = 4.5; 95% CI = 0.9-23.8). CONCLUSIONS: This study suggests that the risk of developing CIN 2-3 is not the same with all variants of HPV16 and that nonprototype-like variants confer a greater risk compared with prototype-like variants. The important genomic differences underlying this increased risk of CIN 2-3 remain to be determined.  相似文献   

5.
This study compared the performances of three human papillomavirus (HPV) detection tests with specimens collected by three alternative procedures. The HPV tests included the Hybrid Capture Tube test (HCT), the microplate-based Hybrid Capture II test (HC II), and the MY09-MY11 L1 consensus primer PCR-based assay. Initial cervical specimens were collected from study subjects with a broom device, and after Papanicolaou smears were made, residual specimens were placed into PreservCyt (PC), a liquid cytology medium. A second specimen was collected from each subject and placed into Digene Specimen Transport Medium (STM). The device for collection of the second specimen alternated with consecutive subjects between a conical cytology brush and a Dacron swab. At the 1.0-pg/ml cutoff, the results of the HC II agreed well with those of the PCR. Specifically, when PCR data were restricted to the types found by the HC II (HPV types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68), there was greater than 90% agreement between the HC II and PCR results with both STM and PC. At a lower cutoff (0.2 pg/ml), HC II-positive results increased further, especially when the test was applied to the PC specimens. However, false-positive HC II results were more often observed at the 0.2-pg/ml cutoff. HC II yielded the highest HPV positivity with specimens placed into PC, followed by specimens collected with a conical brush and placed into STM and, last, by those collected with a Dacron swab and placed into STM. Our results demonstrate the utility of both the STM and PC specimen collection methods and show good agreement between the HC II and PCR.  相似文献   

6.
Women from families with multiple breast and/or ovarian cancers may be at increased risk to develop breast/ovarian cancer themselves. Due to personal experience with family members having these diseases they are anxious and ask for specific prophylactic measurements or treatment. The detection of two susceptibility genes, BRCA1 and BRCA2, has given insight into the genetic background of part of the familial breast/ovarian cancer syndromes. This has led to an increased demand in genetic counselling, testing, and early cancer detection programmes. Prospective data from early cancer detection programmes in this high risk population are yet not available. Based on data from epidemiological risk studies, breast and ovarian screening programmes and follow up data from breast cancer trials recommendations for an early cancer detection programme have been summarized. At the present these recommendations are tested in a prospective trial.  相似文献   

7.
OBJECTIVE: To determine the frequency of, and risk factors for, infections associated with intra-arterial catheters used for cancer chemotherapy. METHODS: Between September 1992 and September 1995, we conducted a surveillance study of all 807 intra-arterial catheters placed for chemotherapy at our center. The insertion site was disinfected with povidone iodine and alcohol, and the arterial catheter was placed using maximal sterile barrier precautions. Upon removal, all intravascular segments were submitted for semi-quantitative culture. RESULTS: No episodes of catheter-related bloodstream infection (95% confidence interval [CI95], 0%-1.6%) were observed. However, the risk of colonization (>15 colony-forming units) of arterial catheters was 15% (CI95, 12%-17%). Retrospective risk-factor analysis conducted on 224 intra-arterial catheters placed for chemotherapy in 1993 showed that colonization was associated significantly with duration of catheterization (median of 1 day for culture-negative catheters vs median of 4 days for culture-positive catheters, P<.001). Age, gender, prior radiotherapy, underlying cancer, neutropenia, and hypoalbuminemia were not associated with catheter colonization. CONCLUSION: Intra-arterial catheters for cancer chemotherapy placed under maximal sterile barrier precautions for a short period of time are associated with a very low risk of bloodstream infection.  相似文献   

8.
Systemic lupus erythematosus (SLE) predominantly affects women (9:1 compared to men) of childbearing age and often decreases its intensity in postmenopausal women, suggesting that sex hormones play a role in its pathogenesis. Comparison of steady-state levels of calcineurin mRNA using RNase protection assays revealed increased calcineurin expression in response to estradiol in cultured T cells from nine female lupus patients. Calcineurin mRNA levels did not increase significantly in T cells from eight age-matched normal control female volunteers. Estrogen-dependent calcineurin mRNA increased in a dose-dependent fashion, while progesterone and dexamethasone did not increase calcineurin mRNA in patient cells. Lupus T cell calcineurin mRNA increased in response to estradiol at 6 h but not at 3 h. Calcineurin phosphatase activity increased in lupus T cell extracts after incubation of cells with estradiol, while phosphatase activity in normal T cells was unaffected by estrogen. Calcineurin expression in T cells from patients with vasculitis and rheumatoid arthritis taking medications similar to those taken by the lupus patients was unaffected by estradiol. This study provides the first evidence for a molecular marker of estrogen action in lupus patients and suggests that estrogen-dependent changes in lupus T cell calcineurin could alter proinflammatory cytokine gene regulation and T-B cell interactions.  相似文献   

9.
Efficient molecular methods are being developed for detecting various types of cytogenetic genetic damage in sperm, especially numerical aneuploidy for chromosomes involved in trisomies that survive at birth. These methods provide new approaches for identifying potentially detrimental environmental exposures, genetic predisposition, chromosomal rearrangements, and physiologic factors which may increase a man's risk of fathering a genetically defective offspring. Corollary methods are also being developed for detecting sperm aneuploidy in laboratory rodents and these will be used to make inter-species comparisons of mutagen sensitivities and for investigating mechanisms of induction and persistence of aneuploidy. Validated assays for detecting genetic alterations in human and rodent sperm (of which sperm aneuploidy is a first example) permit comparisons of somatic and germinal response to mutagens within individuals, comparisons of human and rodent germinal sensitivity to mutagens, and can be applied in an extended parallelogram model to sperm for assessing heritable risk resulting from paternal mutagen exposures.  相似文献   

10.
An antigen-capture enzyme immunoassay (EIA) was developed to detect classical swine fever virus (CSFV) antigen directly from 10% w/v tissue suspension. The assay, based on the sandwich principle, uses a biotinylated monoclonal antibody bound to streptavidin-coated microplates as the capture system and a swine anti-CSFV antibody and rabbit anti-swine HRPO-conjugate as the detector system. The antigen-capture EIA was compared with conventional virus isolation and polymerase chain reaction (PCR) for detection of CSFV in tissues. The ability of the antigen-capture EIA to discriminate classical swine fever (CSF) from bovine viral diarrhea and African swine fever viruses was also tested. The assay was shown to detect 21 different strains of CSFV and was unreactive with tissues from uninfected animals. Signal to noise (S/N) ratios were calculated from the EIA absorbance values. Readings from samples positive by virus isolation (n = 47) averaged a S/N ratio of 5.34. In contrast, samples negative by virus isolation (n = 96) demonstrated a mean S/N ratio of 0.16. At S/N cut-off value of 1.0, all samples that yield virus isolation and PCR negative result were negative in the antigen-capture EIA. Compared with virus propagation in tissue culture using PK15 cells (followed by indirect peroxidase assay detection) and PCR, the EIA had a specificity of 98.7% and a sensitivity of 91.4%. The EIA is simple, can be performed in 4 h and lends itself to automation for screening of tissues sample from pigs suspected of CSFV infection.  相似文献   

11.
A 35-year-old man with non-Hodgkin's lymphoma (NHL) (follicular small cleaved, B cell, stage IVB) received double myeloablative chemotherapy with syngeneic peripheral blood stem cell transplantation (PBSCT). Although platelet recovery was delayed until day 29 after the second transplantation, thereafter trilineage hematopoietic reconstitution was achieved. The evaluation after PBSCT did not detect any residual tumor. The patient was in good health until day 138, when his platelet count suddenly began falling; on day 150, it had fallen to 1.5 x 10(4)/microliter, and the patient was re-admitted for treatment. The bone marrow was normocellular with a normal count and megakaryocyte structure. Other examinations, including serological tests and computed tomography of the neck, chest, abdomen, and retroperitoneum, did not indicate a recurrence of NHL or reveal the cause of thrombocytopenia. The patient's platelet-associated IgG (PAIgG) level was at 70.9 ng/10(7) platelets (normal range: 9-25 ng/10(7) platelets); a diagnosis of thrombocytopenia due to an autoimmune mechanism such as idiopathic thrombocytopenic purpura (ITP) was made. Prednisolone therapy increased the platelet count and reduced the PAIgG level. Thrombocytopenia with an ITP-like mechanism rarely occurs more than 100 days after autologous or syngeneic stem cell transplantation, and should be taken into consideration as a late complication of PBSCT.  相似文献   

12.
Pharmacological characterization of [3H]benzodiazepine binding to membrane preparations of adult rat hippocampus and neonatal rat brain have demonstrated, in addition to the omega 1 and omega 2 populations of central omega benzodiazepine binding sites associated with GABAA receptors, the existence of binding sites with microM affinity for the imidazopyridines zolpidem and alpidem. In the present study we have investigated their comparative autoradiographic distribution using [3H]flumazenil as a ligand. In the neonatal rat CNS, the imidazopyridine derivatives zolpidem and alpidem were found to discriminate two [3H]flumazenil binding site populations with an IC50 value ratio of more than 200-fold. In the different regions investigated (spinal cord, striatum, neocortex and inferior colliculus) the low affinity component had IC50 values of 20-40 microM (zolpidem) and 5-15 microM (alpidem) and accounted for ca. 50% of the total binding site population. In the adult rat, these imidazopyridine derivatives displayed a greater displacing potency in the cerebellum (IC50 = 6 and 36 nM, respectively) than in the hippocampus (IC50 = 37 and 403 nM, respectively). In the cerebellum, [3H]flumazenil binding was fully displaced by 1 microM of either compound and Hill coefficients of displacement curves were close to unity. In the hippocampus, 25% of [3H]flumazenil binding were resistant to 3 microM zolpidem or 1 microM alpidem, but were displaced by 100 microM of either compound. CL 218,872 also displayed a greater displacing potency in the cerebellum (IC50 = 83 nM) than in the hippocampus (IC50 = 711 nM) but [3H]flumazenil binding in the hippocampus was fully displaced by 10 microM of this compound. In adult rat hippocampus, zolpidem and alpidem were found to discriminate between three central omega site subtypes which display high (IC50 = 31 and 6.1 nM, for these imidazopyridine derivatives. In contrast, CL 218,872 discriminated between omega 1 and omega 2 sites but not between two omega 2 receptor subpopulations. omega 1 sites were mainly localized in layer IV of the sensorimotor cortex, cerebellum, substantia nigra, olfactory bulb and inferior colliculus. omega 2I sites were present in the cortical mantle (with higher levels in the cingulate and olfactory than in the sensorimotor cortex) and in subcortical (hippocampus, hypothalamus and nucleus accumbens) limbic structures. In the hippocampus, hypothalamus, spinal cord and nucleus accumbens, omega 2L sites accounted for more than 25% of the specific [3H]flumazenil binding; the density of these sites was minor in the cortex and in most pyramidal and extrapyramidal system structures.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

13.
This is the first in a two-part series of papers dealing with the area of assessing human errors in high risk complex systems. This first paper outlines thirty-eight approaches of error identification, categorising them into types of error identification approach. The paper then reviews these techniques with respect to a broad range of criteria. Viable and non-viable techniques are identified. Trends and research needs are also noted. The second paper proposes a framework or tool-kit approach to Human Error Identification, and presents a prototype methodology to show what such a framework approach would look like in practice, for the nuclear power domain.  相似文献   

14.
New guidelines for the management of patients at risk of developing hypertension and associated conditions have recently been published. These guidelines include a new risk stratification and blood pressure classification, as well as an altered approach to drug therapy. This article describes the major changes from previous recommendations, highlights the role of oral health care providers and emphasizes the dental implications of caring for patients with blood pressure conditions.  相似文献   

15.
Murex hybrid capture DNA assay (HCS) is a solution hybridization antibody capture assay for detection and quantitation of cytomegalovirus (CMV) DNA in leukocytes. To determine whether CMV HCS is sensitive enough to initiate and monitor antiviral therapy after allogeneic stem cell transplantation (SCT), 51 consecutive SCT recipients were prospectively screened for the appearance of CMV infection by HCS, PCR, and culture assays from blood samples. Preemptive antiviral therapy was initiated after the second positive PCR result in all patients, as previously reported, and HCS was not considered for clinical decision making. A total of 417 samples were analyzed. Of these, 21 samples were found to be positive by PCR and HCS, 88 samples were PCR positive but HCS negative, and 308 were negative by both assays. Concordance of results between PCR and HCS and between HCS and blood culture was observed in 78.9 and 95.9% of the samples assayed, respectively. PCR was found to be more sensitive than HCS, and HCS was more sensitive than the blood culture assay (P < 0.0001). Four patients with symptomatic CMV infection were PCR positive prior to the onset of CMV-related symptoms, whereas HCS detected CMV DNA in three patients prior to and one at onset of CMV disease. The numbers of genomes per milliliter of blood were higher in patients with symptomatic CMV infection than in those with asymptomatic CMV infection (P = 0.06). None of the HCS-negative patients developed CMV disease. Thus, all patients with CMV disease were correctly identified by HCS; however, the lower sensitivity limit of the HCS assay may still be insufficient to allow diagnosis of CMV infection early enough to prevent CMV disease in patients following allogeneic SCT.  相似文献   

16.
17.
Cochlear implantation has evolved from its experimental state into a safe and effective therapy for the treatment of profound deafness. Although not applicable to all patients, it offers an alternative to a life in silence. In particular, in early detected and treated deafness in childhood inner ear prostheses have enabled affected persons to be integrated into the world of sound. In addition to the significant impact that therapy has on the life of the individual, there is a social and cultural consequence for society. This is epitomized in the criticism by the deaf community that has resulted in the total rejection of cochlear implants. A critical analysis reveals different personal images prevailing in the deaf community. Knowledge of these differences and their relevance is important for all clinicians involved in counselling a cochlear implant candidate.  相似文献   

18.
19.
The immunological reactivity of 19 operated cases of breast cancer (14 T1 2, 5T3) was investigated before and at 3-weekly intervals up to 12 weeks after radiotherapy by means of a large panel of techniques. The results were compared with two groups of identically-investigated patients, one consisting of 11 cases of cervical cancer (stage III), treated solely by irradiation and the other of 12 cases of cervical cancer (Stages I a and II b), treated by operation only. Before irradiation and in the non-irradiated group cellular immunity appeared to be more disturbed in cases of breast cancer than in cases of cervical carcinoma, as shown by the lowest number of lymphocytes, the lowest number of spontaneously-rosetting lymphocytes, the lowest percentage of DNCB sensitization in patients and the lowest percentage of Tuberculin-positive skin tests. In both types of carcinoma the humoral immunity appeared to be impaired, as apparent from the lowered immune response to tetanus vaccination. Other parameters of humoral immunity such as the immune globulin concentration, iso- and heteroagglutinine, the titre of measles antibodies or membrane fluorescence of lymphocytes showed no dinstinct trends during the investigation period. After irradiation a) inhibiting and b) stimulating influences were observed: a) The incidence and extent of the immune response to tetanus vaccination was further reduced and a distinct lymphopenic effect was observed. b) The incidence of positive skin tests with varidase, as well as the number of spontaneously-rosetting lymphocytes increased after the commencement of irradiation. Apart from the known sensitization with DNCB and skin tests with tuberculin, determination of the antitoxin titre before and after tetanus vaccination provided the most reliable results in regard to immunological reactivity in the investigated tumour patients.  相似文献   

20.
A gas chromatographic method for the analysis of cresol metabolites of toluene and [2H8]toluene in urine was developed. Cresol glucuronides and sulfates in urine were hydrolyzed with beta-glucuronidase and arylsulfatase. Following extraction with tert.-butyl methyl ether and solvent exchange into benzene, the cresols were derivatized with heptafluorobutyric anhydride to form the heptafluorobutyrate esters. The derivatives were analyzed by gas chromatography with electron capture detection. Chromatographic resolution was achieved between all cresol isomers and their 2H7 analogs. Calibration ranged from 0.001 to 500 microg/ml. Recoveries were 55-97% and showed no trend with respect to analyte concentration. Within-day precision of analyses of benchmark urine samples had a coefficient of variation of less than 4%. The assay sensitivity was limited by chromatographic background but was sufficient for quantification of the unlabeled cresols in urine from men with only environmental exposure to toluene. Average levels in urine samples from 45 men were 0.023, 0.054 and 37 microg/ml for o-, m- and p-cresol, respectively.  相似文献   

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