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J Schachter

Publications and source records attributed to J Schachter.

At least 55 records · Page 3Linked to original sources

Sentinel-node guided lymph-node dissection for merkel cell carcinoma.

Merkel cell carcinoma is an aggressive neuroendocrine skin tumour. Treatment is still debatable. Merkel cell carcinoma resembles malignant melanoma in its cutaneous presentation and its embryonic origin; both have unpredictable biological behaviour, early regional lymph node involvement, early distant metastases and a high recurrence rate. In light of these common features, we used pre-operative lymphoscintigraphy, intraoperative lymph-node mapping and sentinel-node biopsy-a well-described technique for the treatment of melanoma-in a 60-year-old man with Merkel cell carcinoma in the right buttock. Following frozen section identification of a metastatic first-order sentinel node, radical right groin dissection was performed. All the other lymph nodes in this basin proved to be disease-free, including the second-order sentinel node and Cloquet node. The patient is now being treated with adjuvant chemotherapy and radiotherapy. This case shows that sentinel-node guided dissection is applicable to Merkel cell carcinoma.

Carcinoma, Merkel Cell↗

Which test is best for chlamydia?

Nucleic acid amplification tests are now the tests of choice for diagnosing Chlamydia trachomatis infection. For the first time there are diagnostic tests for Chlamydia trachomatis that are more sensitive than tissue culture. Another major advantage is that they can be used with first-catch urine specimens and vaginal swabs. It is thus possible to test for genital chlamydial infection without using invasive specimen collection methods.

Journal Article↗

Newly available and future laboratory tests for sexually transmitted diseases (STDs) other than HIV.

BACKGROUND AND OBJECTIVES: The development and introduction of nucleic acid amplification (NAA) tests by commercial sources has improved our ability to diagnose chlamydial infections and other sexually transmitted diseases (STDs). A review of approaches to diagnosing STDs can provide a clearer picture of the present needs. GOALS: To review the advantage and disadvantages of current and future diagnostic approaches. STUDY DESIGN: Survey the literature and define current and future needs in developed and developing country settings. RESULTS: The increase in analytical sensitivity afforded by NAA has enabled the use of noninvasive specimens, such as first-void urine (FVU) and self-obtained vaginal swabs, for diagnostic testing and screening asymptomatic low-prevalence populations and hard-to-access populations. This technology allows multiplexing in which targets from multiple agents responsible for a particular syndrome can be amplified and detected. Although NAA tests have been designed to minimize contamination, there is some reluctance to replace less sensitive tests with this new technology. The concerns involve potential false positive and false negative results caused by the presence of inhibitors, even though the rates of false results are low. Other concerns are cost, through-put, hands-on time, and time necessary for results. CONCLUSIONS: Nucleic acid amplification tests are a great improvement and additional tests are needed for the diagnosis of STDs at the point of first encounter, with minimal delay between diagnosis and treatment. Affordable tests, which are rapid, sensitive, and specific are needed for use in resource-limited settings where most STDs are seen; this has been a major undertaking for the Sexually Transmitted Diseases Diagnostics Initiative.

Clinical Laboratory Techniques↗

Ability of the digene hybrid capture II test to identify Chlamydia trachomatis and Neisseria gonorrhoeae in cervical specimens.

The Digene Hybrid Capture II (HCII CT/GC) test is a combination test designed to detect Chlamydia trachomatis and Neisseria gonorrhoeae in a single specimen. It is a nucleic acid hybridization test which uses signal amplification to increase sensitivity. We compared its performance to that of culture on cervical specimens from 1,370 women. Direct fluorescent-antibody assay was used to resolve discrepant results for C. trachomatis. Samples were collected with a proprietary cervical brush or with endocervical swabs. The HCII CT/GC test proved to be sensitive and specific in detecting these organisms. Compared to N. gonorrhoeae culture, it had a sensitivity of 93% (87/94) and a specificity of 98.5% (1,244/1,263). Compared to C. trachomatis culture, the sensitivity was 97.7% (129/132) and specificity was 98.2% (1,216/1,238). Testing of some specimens with discrepant results by PCR suggested that the test would actually prove to be even more specific if it were compared to a nucleic acid amplification test (NAAT). The sensitivity of C. trachomatis culture was somewhat less, at 88.6% (117/132). The endocervical brush appeared to be better than Dacron swabs for collecting specimens. The HCII CT/GC test offers an attractive format that allows simultaneous detection of C. trachomatis and N. gonorrhoeae with a single specimen. An initial positive result is followed by repeat tests with probes to identify chlamydiae or gonococci. This test is more sensitive than C. trachomatis culture and is at least as sensitive as culture for gonococci. It deserves further evaluation and comparison with NAATs and may well offer an attractive alternative for diagnosis and screening of these infections.

Bacteriological Techniques↗

Reliability of clinical diagnosis in identifying infectious trachoma in a low-prevalence area of Nepal.

The WHO Alliance for Global Elimination of Trachoma by 2020 has increased the need to identify ocular chlamydial infections by clinical examination in areas of both high and low prevalence. The relationship between clinically active trachoma (as defined by clinical examination) and chlamydial infection is known for areas with hyperendemic trachoma, but not for areas with a low prevalence of the clinical disease. In the present study, we examined, photographed, and DNA tested the conjunctivae of children in the Surkhet district of mid-western Nepal, an area known to have a low prevalence of clinically active trachoma. Although 6% of the children aged 10 years and under were found to have clinically active trachoma, none were found to have chlamydia infection by the most sensitive DNA amplification tests available. A very low prevalence of clinically active trachoma is not necessarily evidence of the presence of chlamydial infection. Therefore, the WHO policy of not recommending an intensive trachoma control effort when the prevalence of clinically active trachoma is less than 10% in children is appropriate for this area of Nepal.

Child↗

Risk factors for plasma cell endometritis among women with cervical Neisseria gonorrhoeae, cervical Chlamydia trachomatis, or bacterial vaginosis.

OBJECTIVE: We sought to determine potential risk factors for upper genital tract inflammation in women with cervical Neisseria gonorrhoeae, Chlamydia trachomatis, or bacterial vaginosis. STUDY DESIGN: In a case-controlled study we compared 111 women with cervical Neisseria gonorrhoeae, Chlamydia trachomatis, or bacterial vaginosis (the study group) with 24 women who had negative tests for each of these infections (the control group). We evaluated potential risk factors for upper genital tract inflammation by use of bivariate and then logistic regression analysis. RESULTS: We found plasma cell endometritis in 53 of 111 women in the study group and 3 of 24 controls (odds ratio = 6.4, 95% confidence interval 1.7 to 35.0). On logistic regression, the study group women who were in the proliferative phase had increased likelihood of plasma cell endometritis (odds ratio = 4.5, 95% confidence interval 1.6 to 12.4). CONCLUSION: The proliferative phase of the menstrual cycle seems to be the primary risk factor for ascending infection by organisms associated with pelvic inflammatory disease. This may be due to a hormonal effect or to the loss of the cervical barrier during menstruation.

Adolescent↗

Asymptomatic sexually transmitted disease prevalence in four military populations: application of DNA amplification assays for Chlamydia and gonorrhea screening.

The prevalence of asymptomatic chlamydial and gonococcal infections in male and female military populations was determined using urine-based ligase chain reaction DNA amplification assays (DAAs). Cross-sectional surveys in four military settings revealed an overall prevalence of asymptomatic chlamydial infection of 4.2% (56/1338). This included 3.4% (21/618) of Western Pacific shipboard US Marine Corps enlisted men; 5.2% (21/406) of male marines shore-based in Okinawa, Japan; 2.7% (5/183) of female enlisted US Navy subtender personnel in dry dock; and 6.9% (9/131) of shore-based female naval personnel in San Diego. No gonococcal infections were detected. All subjects were treated within 2 weeks of screening; none of them had progressed to symptomatic disease. General population-based screening for asymptomatic sexually transmitted diseases, and in particular chlamydial infection, can be successfully implemented using urine-based DAA tests. Benefits are maximized in a population in which compliance for follow-up therapy is high.

Adult↗

Chronic follicular conjunctivitis associated with Chlamydia psittaci or Chlamydia pneumoniae.

We determined whether patients with chronic conjunctivitis in whom direct fluorescent antibody (DFA) tests revealed genus-specific chlamydial antigens (but not species-specific Chlamydia trachomatis antigens) were infected with Chlamydia psittaci or Chlamydia pneumoniae. Patients were divided into a case group of possible non-trachomatis chlamydial conjunctivitis and a control group of nonchlamydial conjunctivitis on the basis of examination and DFA testing. Species-specific primers were used to amplify C. trachomatis, C. psittaci, and C. pneumoniae DNA with polymerase chain reaction (PCR). Four (27%) of 15 samples from the case group were positive for C. psittaci or C. pneumoniae DNA, whereas none of 24 control samples were positive. Sequencing revealed a C. pneumoniae, an avian C. psittaci, and two mammalian C. psittaci strains. A short course of oral antibiotic treatment appears to be inadequate for patients with non-trachomatis chlamydial conjunctivitis. Ocular infections due to C. pneumoniae and C. psittaci may be more common than previously recognized and can be identified by DFA and PCR.

Adult↗

A sequential four-drug chemotherapy and biotherapy with interferon alpha and GM-CSF--an innovative protocol for the treatment of metastatic melanoma.

We present the results of our chemo-biotherapy protocol for patients with metastatic melanoma. The rationale for the design of the combined therapy was induction of systemic anti-tumor immunity by: (a) priming with IFN-alpha for enhancement of tumor and histocompatibility antigen expression, (b) therapy by the 4-drug regimen (BCNU, DTIC, cisplatin and tamoxifen) for maximal tumor destruction, followed by (c) an immunomodulatory, low dose of GM-CSF. Treatment was given in cycles of three weeks: first IFN-alpha (3 x 10(6) U/day on days 1, 3, and 5); then the 4-drug regimen given according to Del Prete et al., (4); followed by GM-CSF (20 micrograms/m2/day on days 15 to 21). All patients were previously untreated by chemotherapy, and had a performance status of ECOG 0-2. Treatment was discontinued upon severe toxicity or disease progression. In responding patients--once maximal response was achieved-IFN alpha treatment (3 x 10(6) U/day, three times weekly) was continued for a period of two years or until disease progression. All 40 patients (28 males and 12 females) who received the above program were evaluable for response and toxicity and received at least two cycles of therapy. At a median follow-up of one year, 50% had achieved an objective response, with 22.5% complete responses (CR), and 27.5% partial remissions (PR). Median duration of response is 11 months (12 for CR and 9 for PR patients). Median survival for all patients is 14 months (range, 7-21), increasing to 22 months (range, 15-29) in responding patients. Activation of patients' peripheral blood Macrophages and Dendritic Cells was observed following GM-CSF treatment. The chemo-biotherapy protocol presented above--while associated with acceptable toxicity--resulted in a relatively high response rate with an increase in the number of durable responses in patients with metastatic melanoma.

Adolescent↗

Can serology diagnose upper genital tract Chlamydia trachomatis infections? Studies on women with pelvic pain, with or without chlamydial plasmid DNA in endometrial biopsy tissue.

BACKGROUND: Upper genital tract chlamydial infections in women are on the increase, and serology might be a convenient tool for diagnosis. Evaluations of this approach are needed in women with or without microbiologic evidence of organisms in the upper genital tract. GOALS: To compare the results of antibody assays with cervical culture and upper genital tract histopathology in women with pelvic pain and chlamydial plasmid DNA in endometrial biopsies. STUDY DESIGN: Chlamydia trachomatis plasmid DNA was detected by polymerase chain reaction (PCR) on extracted deparaffinized endometrial biopsy tissue. Five antichlamydial antibody assays were performed measuring total antibodies or immunoglobulin G (IgG), IgM, and IgA classes on sera from 14 women with plasmid DNA as well as 31 without plasmid DNA. RESULTS: Accepting the presence of plasmid DNA as the gold standard, no single test had total diagnostic accuracy. The best sensitivity and specificity occurred with the following assays: whole inclusion fluorescence (WIF) (100% and 80.6%); microimmunofluorescence IgM (MIF IgM) (78.6% and 93.6%); and heatshock protein-60 enzyme immunoassay (42.9% and 100%). Although recombinant anti-lipopolysaccharide enzyme-linked immunosorbent assays measured anti-chlamydial antibodies in a large proportion of these women, specificity was low. The sensitivity and specificity of cervical culture was 28.6% and 100% and of endometrial histopathology was 71.4% and 48.4%. Analysis of patient serological profiles suggested that and 6 women without plasmid DNA may have been cases that were missed by PCR. CONCLUSIONS: Evaluations of assays to diagnosis Chlamydia trachomatis upper genital tract infections could use the presence of organisms or their markers in the upper genital tract as a standard of comparison. Some of these serological assays, such as WIF or MIF IgM, may be helpful in diagnosis, but more studies are needed.

Antibodies, Bacterial↗

Who's afraid of psychoanalytic research? Analysts' attitudes towards reading clinical versus empirical research papers.

The authors point out that psychoanalytic research papers are cited with less frequency than clinical papers, and, presumably, are read with less frequency. Results from two sets of questionnaires from psychoanalysts indicate that a majority of analysts report high levels of conviction in the rationales and techniques in their clinical work. However, analysts with higher degrees of conviction read fewer research papers than analysts with lower degrees of conviction. The authors speculate that analysts with higher degrees of conviction may have an underlying sense of uncertainty about their analytic work. Their uncertainty may generate concerns that research may raise questions and doubts about their rationales and techniques, and, consequently, they have little interest in empirical psychoanalytic research. Such an attitude would be understandable because analysts sense or explicitly believe that confidence in their work is an important, perhaps essential, element in the mutative effects of treatment, and must be maintained and protected. The authors believe that clinical and research approaches have each contributed to the development of psychoanalysis and that both need to be used.

Attitude of Health Personnel↗

A comparison of oral azithromycin with topical oxytetracycline/polymyxin for the treatment of trachoma in children.

Trachoma, an infectious keratoconjunctivitis caused by Chlamydia trachomatis, is a leading cause of preventable blindness in developing countries. In this study we compared oral azithromycin with oxytetracycline/polymyxin eye ointment (once daily for 5 days every 4 weeks; total of six treatment cycles) for the treatment of active endemic trachoma in 168 rural Egyptian children. A suspension of azithromycin was administered to children as a dose of 20 mg/kg by one of three schedules: a single dose, one dose a week for 3 weeks, and one dose every 4 weeks for a total of six doses. The children's clinical status and chlamydial infection rates were evaluated for 1 year. The clinical cure rates were 35% 2 months after initial treatment, 16% at 8 months (during the annual autumn epidemic of purulent conjunctivitis), and 47% at 1 year. The pretreatment chlamydial infection rate of 33% (determined by direct immunofluorescence) decreased to 5% at 2 months and was 9% at 12 months. There were no significant clinical or laboratory differences among the four treatment groups. Thus, 1-6 doses of azithromycin were equivalent to 30 days of topical oxytetracycline/polymyxin ointment and may offer an effective alternative means of controlling endemic trachoma.

Administration, Oral↗