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Biomedical subjects

D Schneider

Publications and source records attributed to D Schneider.

At least 145 records · Page 8Linked to original sources
PubMed1998

Prediction of the survival of patients with advanced ovarian cancer according to a risk model based on a scoring system.

PURPOSE OF INVESTIGATION: The aim of the study was to devise a scoring system based on significantly prognostic parameters which might predict the survival time for each individual patient. METHODS: The study group included 40 patients with stage III or IV invasive ovarian cancer, operated on between 1987 and 1994. Different preoperative and intraoperative parameters were examined and their impact on survival was assessed using the Kaplan-Meier method. Survival rates were compared by the log rank test. The parameters, which have been found to be significant prognostic factors, were incorporated into the final risk model, based on a scoring system. The scores were given according to the cut-off point of each prognostic parameter. A correlation coefficient was calculated from the survival curve, representing the combined scores of individual patients versus their survival. RESULTS: From all studied parameters, only gravidity, the stage of ovarian cancer and the preoperative levels of LDH and CA-125 were demonstrated to have a significant impact on survival. On the basis of these four parameters a scoring system was devised. The scores were given considering the cut-off level of each parameter: gravidity < or = 2 versus > 2; stage of the cancer - IIIA, IIIB and stage IIIC versus stage IV; LDH level < or = 240 versus > 240 U/L; CA-125 < or = 100 versus > 100 U/ml. The average of the combined scores representing the four parameters was the final risk factor, which was plotted against the survival of each individual patient. A correlation coefficient of -0.99 was found. CONCLUSIONS: Our data suggest that the survival of each individual patient with advanced ovarian cancer could be predicted quite accurately considering our risk model based on a scoring system which incorporates four preoperative and intraoperative parameters. This scoring system needs to be validated by larger prospective trials.

Adult↗
PubMed1998

Well-differentiated versus less-differentiated endometrial carcinoma.

The aim of this study was to compare well-differentiated (grade 1) and less-differentiated (grades 2 and 3) endometrial carcinoma, concerning clinical risk factors, presenting symptoms and operative findings. Seventy-one surgically staged endometrial carcinoma cases were reviewed and retrospectively divided according to tumor differentiation into two groups: grade 1 cases (Group I; n=40) and grade 2 and 3 cases (Group II; n=31). No difference was found between the two groups when comparing patient age, gravidity and parity, history of hypertension, diabetes or other malignancies, duration of menopause, number of patients receiving hormonal replacement therapy and histological type of tumor. There was also no difference in presenting symptoms or in duration of uterine bleeding up to the diagnosis of endometrial carcinoma. On the other hand, patients with well-differentiated tumors, as compared to patients with less-differentiated endometrial carcinoma, were significantly more obese (p<0.02), had a smaller uterus (p<0.01) and presented with less advanced stage disease (p<0.0005). The fact that the age of the patients, as well as the duration of uterine bleeding before diagnosis, was similar in both groups may indicate that more advanced cases, as in group II, represent originally a more aggressive tumor rather than progression from a well-differentiated disease. This hypothesis needs further research.

Aged↗
PubMed1998

[Occurrence of onchocerciasis in subjects coming from non-endemic areas and migrating to a hyperendemic area].

The incidence of Onchocerca volvulus infection was measured from 1992-93 to 1995 in six villages of initially uninfected migrants who settled in 1991 in the Vina Valley (Cameroon), an area of ongoing transmission of onchocerciasis. The mean annual incidence (MAI) exceeded 20% in the three communities located in the first line, and fewer than 15 km from the hyperendemic areas of the Central African Republic. The MAI was lower than 16% in the second line communities. As these populations are particularly at risk of developing ocular complications from onchocerciasis, it is recommended that repeated ivermectin distributions be organized in the migrant villages of the Vina Valley.

Animals↗
PubMed1997

Itraconazole maintenance treatment for histoplasmosis in AIDS: a prospective, multicenter trial.

PURPOSE: To study the efficacy and safety of maintenance treatment with itraconazole for disseminated histoplasmosis in patients with AIDS. PATIENTS AND METHODS: This was a prospective, multicenter, open-label study conducted at university-based hospitals participating in the AIDS Clinical Trial Group (ACTG). Forty-six AIDS patients with mild to moderate disseminated histoplasmosis who had successfully completed 12 weeks of induction treatment with itraconazole were treated with itraconazole, 200 mg once daily (42 patients) or 400 mg once daily (4 patients). Patients were followed at monthly intervals with clinical and laboratory assessment for relapse or toxicity. Primary outcome measures were relapse of histoplasmosis and survival. Secondary outcome measures included drug-limiting toxicity and changes in serum and urine Histoplasma polysaccharide antigen (HPA) levels. RESULTS: Two patients relapsed during a median follow-up period of 87 weeks. The 1-year relapse-free rate was estimated to be 95.3% (95% CI, 85.3%-99.7%). One relapse may have been related to poor adherence to treatment and the second to concurrent administration of rifampin. From the start of maintenance treatment, the estimated 1-year survival rate was 73.0% (95% CI, 67.5%-77.9%). Five patients discontinued treatment because of suspected drug toxicity, three of whom had possible or probable hepatotoxicity. Median serum and urine HPA levels declined significantly during treatment. The only patient in whom antigen levels rose >2 U developed clinical relapse 1 week later; antigen levels were unavailable in the other relapsing patient. CONCLUSIONS: Itraconazole, 200 mg daily, is effective in preventing relapse of disseminated histoplasmosis in patients with AIDS. It is generally well tolerated, but clinicians should be alert for drug interactions and possible hepatotoxicity.

AIDS-Related Opportunistic Infections↗
PubMed1997

Serum neuron-specific enolase levels do not increase after electroconvulsive therapy.

BACKGROUND: Cognitive disorders occurring after electroconvulsive therapy (ECT) are regarded as an expression of brain damage, despite computed tomography (CT) and magnetic resonance imaging (MRI) showing no signs of structural brain damage. Serum neuron-specific enolase (NSE) is a sensitive marker of neuronal damage (i.e., after stroke or cardiac arrest). The objective of this study was to investigate whether ECT leads to a rise in the serum NSE level as an expression of neuronal damage. METHODS: We investigated seven patients (four women, three men; mean age 6212 years) with major depressive disorder, who were treated with ECT for the first time. ECT was administered every 2 days, three times a week under standard conditions (anaesthesia: thiopental, succinylcholine, 100% oxygen, unilateral ECT, seizure duration more than 20 s). Blood samples were drawn at the following times. For the first ECT: 15 and 1 min before ECT, and 1, 5, 10, 15, 20, 25, 30, 45, 60, 75, 90, 105, 120 min, and 8, 12, 24 h after ECT. For all subsequent ECT: 1 min before and 4 h after every ECT. Serum NSE was measured by means of enzyme immunoassay (Cobas Core NSE, EIA, Hoffmann-La Roche). RESULTS: On average, each patient underwent ECT 10 times (range 5-20). In the first ECT there was no difference in serum NSE levels before and at all times following ECT. A comparison of serum NSE levels before and after each subsequent bout of ECT revealed no differences. Moreover, comparing the baseline serum NSE levels (before the first ECT) with the values after final ECT showed no differences either. CONCLUSION: ECT did not increase serum NSE values, indicating that electroconvulsive therapy does not cause neuronal damage.

Aged↗
PubMed1997

Characterization of the solution complex between the interferon-induced, double-stranded RNA-activated protein kinase and HIV-I trans-activating region RNA.

The antiviral activity of the interferon-induced, double-stranded RNA (dsRNA)-activated protein kinase (PKR) is mediated through dsRNA binding leading to PKR autophosphorylation and subsequent inhibition of protein synthesis. Previous biochemical studies have suggested that autophosphorylation of PKR occurs via a protein-protein interaction and that PKR can form dimers in vitro. Using four independent biophysical and biochemical methods, we have characterized the solution complex formed between PKR and trans-activating region (TAR) RNA, a 57-nucleotide RNA species with double-stranded secondary structure derived from the human immunodeficiency virus type I genome. Chemical cross-linking and gel filtration analyses of PKR.TAR RNA complexes reveals that TAR RNA addition increases PKR dimerization and results in the formation of a solution complex with a molecular weight of approximately 150,000. Addition of TAR RNA to PKR results in a quenching of tryptophan fluorescence, indicative of a conformational shift. Through small angle neutron scattering analysis, we show that PKR exists in solution predominantly as a dimer, and has an elongated solution structure. Addition of TAR RNA to PKR causes a significant conformational shift in the protein at a 2:1 stoichiometric ratio of protein to RNA. Taken together, these data indicate that the PKR activation complex consists of a protein dimer bound cooperatively to one dsRNA molecule.

Base Sequence↗
PubMed1997

CO2 laser surgery for verrucous carcinoma of the larynx.

BACKGROUND: The verrucous carcinoma (VC) is a low grade malignant tumor. Treatment strategies of VC of the larynx are topics of the ongoing discussion, and the role of the carbon dioxide laser therapy in the management remains unclear to date. STUDY DESIGN/MATERIALS AND METHODS: From 1986 to 1995, 21 patients with glottic VC were treated with transoral carbon dioxide laser surgery. Follow-up ranged from 6 to 122 months (mean 52). RESULTS: In T1 lesions, a complete removal of the tumor was possible with laser-cordectomy in ten cases and with extended laser cordectomy in four cases. In seven patients suffering from T2 carcinoma, a partial laser laryngectomy was performed. There was no tumor-related death in this series. No patient required laryngectomy or radiotherapy. CONCLUSION: The results presented here are superior to those previously reported with radiotherapy. They add further support to the observation that surgery is the better treatment option for VC of the larynx. Based on the results of this study, recommended treatment for T1 and T2 VC is oncologic CO2 laser surgery in combination with a meticulous follow up for early recognition of local recurrence.

Adult↗
PubMed1997

Peritoneal fluid lactate dehydrogenase in ovarian cancer.

In attempt to identify patients with ovarian carcinoma and differentiate them from patients with benign ovarian tumor or other gynecological malignancies, peritoneal fluid and serum lactate dehydrogenase (LDH) levels were measured in 51 patients: 15 with ovarian carcinoma, 15 with endometrial carcinoma, 4 with cervical carcinoma, and 17 with benign ovarian tumor. Peritoneal fluid and serum LDH levels in ovarian cancer patients were significantly higher than those in patients with benign ovarian tumor (P < 0.001) or other gynecological malignancies (P < 0.001 and P < 0.03, respectively). Yet, peritoneal fluid LDH demonstrated higher diagnostic sensitivity (87%) and greater diagnostic accuracy (90%) than serum LDH (60 and 77%, respectively) or serum CA-125 (73 and 83%, respectively). Comparing the histological types of ovarian cancer, serous cystadenocarcinoma presented higher peritoneal fluid LDH levels than endometrioid or mucinous cystadenocarcinoma. No difference in peritoneal fluid LDH was observed comparing different stages of ovarian cancer. The results suggest that peritoneal fluid LDH may be an efficient biochemical marker in diagnosis of ovarian cancer.

Adolescent↗
PubMed1997

Treatment of histoplasmosis with fluconazole in patients with acquired immunodeficiency syndrome. National Institute of Allergy and Infectious Diseases Acquired Immunodeficiency Syndrome Clinical Trials Group and Mycoses Study Group.

PURPOSE: This study assesses the efficacy and safety of fluconazole therapy in patients with acquired immunodeficiency syndrome (AIDS) and mild to moderately severe manifestations of disseminated histoplasmosis. PATIENTS AND METHODS: This was a multicenter, open-label, nonrandomized prospective trial. All patients had AIDS and disseminated histoplasmosis. Patients were treated with 1,200 mg of fluconazole given by mouth once on the first day, then 600 mg once daily for 8 weeks, and those patients who improved clinically were then assigned fluconazole maintenance therapy 200 mg once daily for at least 1 year. Interim analysis revealed a high failure rate (10 of 20, 50%), causing revision of the protocol to increase the fluconazole dose to 1,600 mg given once on the first day, then 800 mg once daily, and the duration to 12 weeks for induction therapy and then 400 mg daily for 1 year for maintenance therapy. MEASUREMENTS AND MAIN RESULTS: Thirty-six of 49 patients (74%; 95% confidence interval [CI]: 59% to 85%) with mild to moderately severe clinical manifestations who entered into the revised study responded to 800 mg of fluconazole daily for 12 weeks as induction therapy. Of the seven patients who failed induction therapy because of progression of histoplasmosis, one died of the infection. Of 36 patients who entered into the maintenance phase of the study receiving 400 mg of fluconazole daily for 1 year, 11 (30.5%) relapsed, including one who died (2.8%). Two of the 49 patients (4.1%) were removed because of grade 4 adverse events, alkaline phosphatase elevation for one and aspartate aminotransferase elevation in the other. The relapse-free rate at 1 year was 53% (95% CI: 32% to 89%), prompting closure of the study. CONCLUSIONS: Fluconazole 800 mg daily is a safe and moderately effective induction therapy for mild or moderately severe disseminated histoplasmosis in patients with AIDS. On the basis of historic comparison, fluconazole 400 mg daily is less effective than itraconazole 200 to 400 mg daily or amphotericin B 50 mg given weekly as maintenance therapy to prevent relapse.

AIDS-Related Opportunistic Infections↗
PubMed1997

Beyond habituation: long-term repetition effects on visual event-related potentials in epileptic patients.

Sixteen patients with partial epilepsy learned to produce positive or negative slow cortical potential shifts in a biofeedback condition during 20 consecutive training sessions. Visual ERPs to the presentation of the feedback and the discriminative stimulus were recorded at vertex. Regardless of the subjects' task (positivity versus negativity), amplitudes of the P2 (mean peak latency about 225 ms) and P3a (322 ms) components decreased across sessions, resulting in appearance and subsequent enhancement of a negative wave N2 (298 ms) between P2 and P3a. As N2 grew the P2 latency decreased and the P3a latency increased. Additionally, the P3b (472 ms) decreased with repetition, however, it did so slower than P2 and P3a. A comparison between the present data, on the one hand, and those obtained in the ERP habituation paradigm within one session, on the other hand, indicates that some repetition effects cannot be explained by habituation.

Adult↗
PubMed1997

Spiritual care for children with cancer.

OBJECTIVES: To review literature pertinent to spirituality of children with cancer and to identify practical strategies for providing care for this dimension in children. DATA SOURCES: Nursing research and literature about pediatric nursing care and spirituality; theoretical formulations of Piaget, Fowler, and Erikson. CONCLUSION: Children diagnosed with cancer have unique spiritual needs that place them at risk for developing spiritual distress. With the diagnosis may come experiences of loss of normalcy, physical stamina, relationships, body image, and future goals. Spiritual care includes interventions that assist children to find meaning and purpose in life, to continue relationships, and to transcend beyond the self. IMPLICATIONS FOR NURSING PRACTICE: Spiritual care includes caregiver and child assessment and interventions appropriate to the developmental stages of infancy through adolescents. Tables outlining how this can be done by oncology nurses are included.

Adolescent↗
PubMed1997

Region of birth, migration and homicide rates of African Americans.

A study was made of all homicide deaths among black Americans during the period 1979-1991 in order to test two competing hypotheses about region of birth and region of death. One hypothesis was that Southern-born blacks had the highest homicide rates in every region of the US. The competing hypothesis was that blacks who did not migrate out of their region of birth had the highest homicide rates. We found that Southern-born blacks had the highest homicide rates among the population 35+ years old in the Northeast, Midwest, South and West. Yet non-migrants (region-born population) had higher rates than their Southern-born counterparts among the population 15-34 years old. Long distance migrants who were born in the Northeast, West or were foreign-born had the lowest homicide rates, by far. The distressing implications of these findings for public health efforts to prevent violent death are discussed.

Adolescent↗
PubMed1997

Therapy of myasthenic crisis.

OBJECTIVES: To investigate the frequency, causes, and characteristic features of the course of isolated myasthenic crisis (defined as acute respiratory failure with the need for mechanical ventilation). To compare the effectiveness of three different therapeutic regimens (i.e., continuous intravenous infusion of pyridostigmine, pyridostigmine plus prednisolone, and plasma exchange) in terms of duration of ventilation and outcome of patients with myasthenic crisis. DESIGN: Population-based retrospective study covering the period 1970 to 1995. SETTING: University hospital, center for myasthenia gravis in Saxony, Germany. PATIENTS: Of 235 patients with myasthenia gravis treated at our institution, 44 patients developed a total of 63 myasthenic crises (average annual incidence 2.5%). INTERVENTIONS: Myasthenic crises were treated with pyridostigmine (n = 24), pyridostigmine plus prednisolone (n = 18), and plasma exchange (n = 21). MEASUREMENTS AND MAIN RESULTS: There were no significant differences between the three treatment groups with respect to clinical characteristics, duration of mechanical ventilation, complications, and outcome on release from intensive care and after 3 months. Eleven (17%) patients had severe cardiac arrhythmia, which ended fatally for six patients. CONCLUSIONS: None of the therapeutic regimens applied demonstrated any advantage over the others. All three regimens used were found to be effective and should be applied depending on the circumstances prevailing. Patients with myasthenic crisis must undergo careful cardiac monitoring, and temporary pace-making should be provided where clinically indicated.

Humans↗
PubMed1997

Perioperative complications of percutaneous dilational tracheostomy.

Percutaneous dilational tracheostomy (PDT) has replaced conventional tracheostomy for long-term intubated patients in many intensive care units (ICUs). In a prospective study carried out between September 1994 and August 1996, 76 patients underwent PDT. In 41 patients, PDT was performed "blind." In 35 patients it was executed with simultaneous bronchoscopic monitoring. The type and rate of complications of the two techniques were compared. Comparing the groups with and without bronchoscopy, the perioperative complication rate was equivalent (7% vs 6%); however, more severe complications occurred in the group without bronchoscopy (one death due to tension pneumothorax, two cases of perforating the rear tracheal wall) than in the group with bronchoscopy (two cases of intratracheal hemorrhage). PDT is a suitable bedside method for ICU patients undergoing long-term ventilation. Simultaneous endoscopy minimizes the severity of complications.

Adult↗