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J Witte

Publications and source records attributed to J Witte.

At least 19 recordsLinked to original sources
PubMed1992

Prognostic significance of micrometastatic tumour cells in bone marrow of colorectal cancer patients.

Much of the information recorded at the time of surgery for malignant disease has been used, alone or in combination, to indicate the outlook for that patient, including probability of metastasis. However, direct evidence of tumour seeding in distant organs at that time is not available. An immunocytochemical assay for the epithelial cytokeratin protein (CK18) may fill this gap since it is a feature of epithelial cells but would not normally be in bone marrow. We looked for disseminated tumour cells preoperatively in bone marrow from 88 patients with radically resected colorectal carcinomas. Smears for 28 (32%) patients were positive for cells of epithelial origin, which were absent from aspirates taken from 102 controls with non-malignant disease. The prognostic value was assessed in a follow-up study with a median observation time of 35 (12-58) months. Patients who had bone marrow tumour cells in the aspirate showed a significantly shorter disease-free survival than those without tumour cells (p = 0.0084). In a Cox regression model multivariate analysis demonstrated that the finding of tumour cells in bone marrow is an independent, significant (p = 0.0035) determinant of relapse. Although the skeleton is not a preferred site of overt metastasis in colorectal cancer the demonstration of tumour cells in bone marrow has to be taken as evidence of the general disseminative capability of an individual tumour.

Adenocarcinoma↗
PubMed1992

Transmission of human immunodeficiency virus in a dental practice.

OBJECTIVE: To determine if patients of a dentist with the acquired immunodeficiency syndrome (AIDS) became infected with human immunodeficiency virus (HIV) during their dental care and, if so, to identify possible mechanisms of transmission. DESIGN: Retrospective epidemiologic follow-up of the dentist, his office practice, and his former patients. SETTING: The practice of a dentist with AIDS in Florida. PARTICIPANTS: A dentist with AIDS, his health care providers and employees, and former patients of the dentist, including eight HIV-infected patients. MEASUREMENTS: Identification of risks for HIV transmission (if present), degree of genetic relatedness of the viruses, and identification of infection control and other office practices. RESULTS: Five of the eight HIV-infected patients had no confirmed exposures to HIV other than the dental practice and were infected with HIV strains that were closely related to those of the dentist. Each of the five had invasive dental procedures, done by the dentist after he was diagnosed with AIDS. Four of these five patients shared visit days (P greater than 0.2). Breaches in infection control and other dental office practices to explain these transmissions could not be identified. CONCLUSION: Although the specific incident that resulted in HIV transmission to these patients remains uncertain, the epidemiologic evidence supports direct dentist-to-patient transmission rather than a patient-to-patient route.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Sexual practices in the transmission of hepatitis B virus and prevalence of hepatitis delta virus infection in female prostitutes in the United States.

OBJECTIVE: To evaluate heterosexual transmission of hepatitis B virus (HBV) and the prevalence of hepatitis delta virus (HDV) infection in female prostitutes. DESIGN: Survey. SETTING: Sexually transmitted disease clinics, drug treatment programs, detention centers, and/or outreach efforts in eight areas in the United States. PARTICIPANTS: A total of 1368 female prostitutes 18 years of age or older. OUTCOME MEASURES: Seropositivity for HBV and HDV infection. RESULTS: The overall prevalence of past or present HBV infection was 56%: 74% in women who were injecting-drug users (IDUs), 38% in women reporting no history of injecting-drug use (non-IDUs), 51% in whites, 55% in blacks, and 67% in Hispanics. Of 21 HBV carrier IDUs, 21% had HDV infection; of 18 HBV carrier non-IDUs, 6% had HDV infection. In non-IDUs (49%), risk factors for HBV infection were a history of having penile-anal intercourse (odds ratio [OR], 3.1; 95% confidence limits [CL], 1.3, 7.3) and seropositivity for syphilis and human immunodeficiency virus (HIV) infection. In IDUs, factors associated with an increased risk of infection, in addition to behaviors related to injecting-drug use, were the number of lifetime sexual partners, having sexual partners from groups at high risk for HBV infection, and seropositivity for syphilis and HIV infection; spermicide and/or diaphragm use was associated with a markedly decreased risk of HBV infection among blacks (OR, 0.1; 95% CL, 0.03, 0.4) and Hispanics (OR, 0.2; 95% CL, 0.06, 0.9). CONCLUSION: This is the first study to suggest that having anal intercourse and failing to use vaginal contraceptives may facilitate transmission of HBV to women. Our data support guidelines that recommend hepatitis B vaccination for prostitutes and persons with a history of sexually transmitted diseases or multiple sexual partners.

Adolescent↗
PubMed1991

Micrometastatic tumour cells in bone marrow of patients with gastric cancer: methodological aspects of detection and prognostic significance.

Monoclonal antibodies (Mab) are potent probes to identify individual tumour cells or small tumour cell clusters in bone marrow. In the present study, various antibodies directed against either cell surface or intracytoplasmic antigens of epithelial cells were assessed for their ability to detect such cells in bone marrow of patients with breast, colorectal and gastric cancer. According to the presented data, monoclonal antibodies against intracellular cytokeratin (CK) components are superior in terms of specificity and sensitivity to antibodies reacting with epitopes of the cell membrane. Using a monoclonal antibody against the cytokeratin polypeptide 18 in connection with the alkaline phosphatase anti-alkaline phosphatase detection system (APAAP), we could detect tumour cells in bone marrow of 34 out of 97 patients with gastric cancer examined at the time of primary surgery. The incidence of positive findings was correlated to established risk factors, such as histological classification and locoregional lymph node involvement. Clinical follow-up studies on 38 patients demonstrated a significantly increased relapse rate in patients presenting with CK-positive cells in their bone marrow at the time of primary surgery. Thus the described technique may help to identify patients with gastric cancer carrying a high risk of early relapse.

Antibodies, Monoclonal↗
PubMed1991

[Surgical indications in cricopharyngeal dysfunction].

In 1989, five patients were treated for a cricopharyngeal dysfunction by cervical myotomy. In the past, due to extremely limited indications for surgery, repeated efforts of conservative treatment had been attempted in patients with idiopathic cricopharyngeal dysfunction and tracheopulmonary aspiration and/or permanent inability of oral nourishment. These patients underwent surgery after an interdisciplinary clinical assessment. Four out of five patients showed immediate improvement of their serious symptoms. Cervical myotomy is not expected to be successful in patients with insufficient oropharyngeal propulsion, as we could see in one female patient with severe upper oesophageal sphincter spasm. According to the literature and to our results, approximately 70 to 90% of the patients with idiopathic dysfunction of the cricopharyngeal muscle, who underwent surgery, showed significant improvement or even recovery. Due to the multifactoral genesis of the cricopharyngeal dysfunction it is understandable, that the surgical result is heavily dependent on the preoperative interdisciplinary diagnosis. In summary, for idiopathic cricopharyngeal dysfunction with complications we recommend the early and technically simple operation.

Aged↗
PubMed1990

[Non-medicinal therapy tachycardiac arrhythmias].

The conservative antiarrhythmic treatment was improved by the introduction of the Holter-ECG technique, of the serial electrophysiological testing and by new antiarrhythmic drugs. An essential enhancement of the therapeutic possibilities, particularly when ineffectiveness, proarrhythmic action or intolerance of the medicaments are existing, are increasingly the non-medicamentous techniques of the antiarrhythmic therapy. Thus the treatment of arrhythmia has become by far more effective, but at the same time also more complicated and more expensive. Between 1980 and 1989 altogether 53 patients were treated with anti-tachycardiac pacemakers (25), with an ablation of the bundle of His by means of catheter-mediated DC-shock application (20), with a direct surgical interruption of the bundle of Kent (5) as well as with the implantation of an automatic cardioverter/defibrillator (3). Indications, techniques and results of the individual methods are represented.

Electric Countershock↗
PubMed1990

Seroprevalence and risk factors for HTLV-I/II infection among female prostitutes in the United States.

We tested 1305 female prostitutes from eight areas of the United States for antibodies to human T-cell lymphotropic virus type I/II. Overall, 6.7% were human T-cell lymphotropic virus type I/II seropositive (with antibodies to both gag and env gene products). The seroprevalence rates ranged from 0% in southern Nevada to 25.4% in Newark, NJ. Human T-cell lymphotropic virus type I/II seropositivity was independently associated with race (odds ratio, 4.68), intravenous drug use (odds ratio, 2.94), hepatitis B seropositivity (odds ratio, 2.87), recruitment in Newark (odds ratio, 2.34), and more years of sexual activity (odds ratio, 1.08 per year of sexual activity). Groups with high rates included blacks, Hispanics, and American Indians, and the rates in these groups were significantly higher than among whites and Asian Americans for women both with and without a history of intravenous drug use. Among intravenous drug users, the only other independent associations were more years of sexual activity and recruitment in Newark; and in non-intravenous drug users, hepatitis B seropositivity. These data show that human T-cell lymphotropic virus type I/II infection is present among female prostitutes in some areas of the United States. Further studies are needed to evaluate patterns of transmission and long-term health effects.

Acquired Immunodeficiency Syndrome↗
PubMed1990

The biosynthetic basis of adult lactase deficiency.

The intestinal brush-border enzyme lactase splits lactose into its component monosaccharides, glucose and galactose. Relative deficiency of the enzyme during adulthood is a common condition worldwide and is frequently associated with symptoms of lactose intolerance. We studied the synthesis and processing of lactase in normal and adult hypolactasic subjects using human intestinal explants in organ culture. Metabolic labeling experiments in our control subjects with [35S]methionine followed by immunoprecipitation, sodium dodecyl sulfate-polyacrylamide-gel electrophoresis, and fluorography demonstrated that newly synthesized lactase is initially recognized as a precursor molecule with a relative molecular weight (Mr) of 205,000. Over the course of several hours most of the labeled lactase was converted to a mature form of 150,000 Mr. Transiently appearing forms of 215,000 and 190,000 Mr were identified and were felt to represent intermediary species generated during intracellular processing. We identified two distinct alterations in lactase biosynthesis accounting for adult hypolactasia. Studies in three deficient subjects demonstrated markedly reduced synthesis of the precursor protein though posttranslational processing appeared identical to normal. Multiple studies in a fourth deficient subject demonstrated synthesis of ample amounts of precursor lactase but reduced conversion to the mature active form of the enzyme.

Adult↗
PubMed1990

Epithelial tumor cells in bone marrow of patients with colorectal cancer: immunocytochemical detection, phenotypic characterization, and prognostic significance.

A monoclonal antibody (mAb) directed against the cytokeratin (CK) polypeptide no. 18 specifically expressed in cells derived from simple epithelia was used to detect epithelial tumor cells in bone marrow aspirates. Of 156 patients with colorectal carcinoma, 42 presented with cells at the time of primary surgery. The incidence of positive findings varied considerably with the size and the localization of the primary tumor, the involvement of regional lymph nodes, and the presence of clinically manifest metastases. Applying a sensitive double-staining procedure, we could demonstrate that epithelial cells in bone marrow showed a heterogeneic expression of receptors for epidermal growth factor (EGF-R) and transferrin (Tf-R) as well as of the proliferation-associated Ki67 antigen. Also human leukocyte antigen (HLA) class I antigens differed widely in their expression on the CK-positive cells. Clinical follow-up studies on 85 patients showed a significantly higher relapse rate in patients presenting with CK-positive cells in their bone marrow at the time of primary surgery. Twenty-three patients were monitored for the presence or absence of CK-positive cells in bone marrow over time. The majority of monitored patients (18 of 23) exhibited a constant pattern of immunocytochemical findings during the time of observation. Thus, the technique may be useful in identifying high-risk patients as well as in monitoring adjuvant therapeutic trials.

Antibodies, Monoclonal↗
PubMed1990

[Becoming a surgeon--at the large community hospital].

There is no correlation between the number of places for surgical education and the real demand for surgeons. In Bavaria 86.7% of all surgeons licensed to train surgeons between 1-6 ys. took part in an inquiry. They asked for 25-30% surgeons in their residency staff but got only 8-24% in reality. In addition 60.2% of all resident wait for a place to finish their surgical training in fully licensed hospitals. In a big community hospital there are no problems for residents to get the needed number of operations. Beside this surgical education should include 6 months clinical training in ICU, 2.5 ys. general, 1.5 trauma and 1 year vascular-thoracis surgery. Basic science and research can be done only in universities, but clinical control of patients outcome, i.e. in tumor patients is mandatory.

Curriculum↗
PubMed1990

[Lactic acidosis--recognition and treatment of an important complication of perioperative parenteral nutrition].

We report 5 cases of acute vitamin B-1 induced lactic acidosis in surgical patients receiving parenteral nutrition. In all patients treatment with vitamin B-1 induced a dramatical improvement of clinical findings. 4 patients recovered completely, 1 patient died from already developed irreversible cardiocirculatory failure. These cases underline the need for regular vitamin B-1 substitution in patients with parenteral nutrition and preoperatively in alcoholics and in patients, in whom a sufficient food intake can not be assured.

Acidosis, Lactic↗
PubMed1989

[Bone marrow micrometastases in colorectal cancers].

To date, the detection of individual micrometastases or disseminated tumor cells has not been possible with conventional diagnostic procedures. With the aid of new immunocytochemical investigation, however, histogenetically different cells can now be detected in the bone marrow. The monoclonal antibody, cytokeratin component 18, is most suitable for the detection of micrometastases from colorectal carcinoma. In 22 out of 82 patients with colorectal carcinoma, we were able to detect CK2-positive cells. The incidence of these "micrometastases" is represented as a function of primary tumor size, lymph node involvement, distant metastasis, and degree of malignancy of the tumor, age and sex of the patient, and tumor localization.

Adult↗
PubMed1989

[The academy for surgical postgraduate education and practical continued education of the Professional Society of German Surgeons].

The aim of the academy is to present an up-to-date knowledge of all fields of surgery to young surgeons in the 5th/6th year of education. The main topics are taken from general, trauma, vascular, pediatric, neuro- and heart-surgery. The meetings are held once per year in five different cities in Germany. The second branch of the academy is an annual symposium dealing with five different current events that will be discussed each for half a day. Furthermore there is offered a course for ultrasound and another for endoscopy.

Curriculum↗
PubMed1989

Current status of anti-bradycardial electrotherapy.

A review of the current status of cardiac pacing in the treatment of cardiac bradyarrhythmias is presented. The article describes the indications, haemodynamic principles of differentiated treatment and the technical potential of a new generation of (multi-mode and multi-parameter programmable, rate responsive) devices.

Bradycardia↗
PubMed1989

Results of pacemaker therapy in the German Democratic Republic. Organizational, methodological and technical aspects.

A review of the organizational, methodological and technical aspects of pacemaker therapy in the German Democratic Republic is presented. It underlines the importance of expeditious decentralization of cardiac pacing centres and the role played by an inter-disciplinary working group made up of cardiologists, surgeons and health-care engineers in establishing a uniform therapeutic standard. On the basis of data provided by the nation-wide registry of pacemaker therapy, statistical data on the numbers of pacemaker implantations, patient distribution by age and sex, indications and methods of pacemaker implantation and the types of devices employed are presented. Moreover, the current standard of technical development of pacemaker therapy in the German Democratic Republic is evaluated drawing on an analysis of this country's programme of pacemaker manufacture.

Adolescent↗