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Biomedical subjects

J Ritter

Publications and source records attributed to J Ritter.

At least 235 records · Page 13Linked to original sources
PubMed1986

Frequency and clinical significance of DNA aneuploidy in acute leukemia.

Analyses of the cellular DNA content were carried out in 446 patients with newly diagnosed acute myeloid (AML) and lymphoblastic (ALL) leukemias in order to assess the frequency of DNA aneuploidies and its relation to immunologic and morphologic subtypes as well as its prognostic relevance. Based on high resolution FCM analyses and standardized reference measurements, DNA aneuploidies were identified at a similar frequency in children and adults with AML (38.0% and 40.0%) and ALL (40.0% and 37.4%). In AML aneuploid DNA stemlines were significantly less frequent in FAB-M 1 cases as compared to the other morphologic subtypes (p less than 0.05), whereas the degree of DNA aneuploidy was significantly lower in M 1 and M 2 leukemias as compared to the M 4 and M 5 subgroups (p less than 0.05). In ALL non-T/non-B and C-ALL revealed a higher frequency of DNA aneuploidies than T- and Null-ALL cases (p less than 0.05). No differences in the response to induction therapy were found between patients with and without DNA aneuploidy in children or adults with AML or ALL. In the childhood ALL trial BFM 79/81, however, a significantly higher frequency of long term remissions was observed in children with DNA aneuploidy (0.91 versus 0.66 at five years, p = 0.053). A similar though not significant tendency was also revealed from the AML studies BFM 78 in children and 78/81 in adults. In the subsequent studies these differences could not be confirmed at present, possibly because of the considerably shorter observation time.

Adult↗
PubMed1986

[Risk groups in acute, non-lymphatic leukemia in childhood. Analysis of the results of the cooperative therapeutic studies AML-BFM 78 and 83].

The analysis of the treatment results of the co-operative therapy studies BFM 78 and 83 for the treatment of acute myelogenous leukemia in children revealed the following risk factors: Death before the onset of therapy and early death occurred more frequently in children with acute monoblastic/monocytic leukemia and in children with initial WBC of greater than 100,000/microliters than in the other patient groups. The remission rate was lower in children with an initial WBC greater than 100,000/microliters (56%) than in children with an initial WBC less than 100,000/microliters (86%). In study BFM 78 the probability of a relapse free interval of 6 years is significantly lower in children with an initial WBC greater than 100,000/microliters (pCCR = 28%; SD 11%) than in children with an initial WBC less than 100,000/microliters (pCCR = 64%; SD 10%). The median follow up time is 4 3/4 years (range 2 3/4-6 3/4 years). The probability of an event free interval of 3 years was significantly lower in children with initial involvement of the CNS (pCCR = 24%, SD 12%) than in children without involvement of the CNS (pCCR = 50%; SD 5%).

Adolescent↗
PubMed1986

[Salmonella osteoarthritis in hemophilia A].

The unexpected course of a hemarthrosis in a young man with severe hemophilia and septic osteoarthritis is described. The arthritis appeared first as a relapse of a series of hemarthroses . However, the further course of the disease led to the diagnosis of a salmonella osteoarthritis.

Adult↗
PubMed1986

[Value and indications for nipple stimulation in obstetrics].

The authors have evaluated the effect of stimulation of the breast on uterine tone in a series of 25 patients at term where induction of labour was indicated for obstetric reasons. In 64% of cases breast stimulation carried out for 30 minutes was followed by uterine contractions. In 20% of these cases the authors found that the uterus contracted strongly and in two patients so strongly as to cause fetal heart slowing. Breast stimulation matures the cervix slightly but this is not statistically significant for Bishop's score. In 16% of case breast stimulation provoked labour. Analysing these results and studying the literature shows that the effect is linked to the degree of cervical maturity at the onset and the effect of stimulation depends also on the length of time the stimulation was carried out. In practice the use of breast stimulation is limited because of the risks of hypertonic contractions and this is turn requires careful fetal heart monitoring.

Adolescent↗
PubMed1985

Treatment of acute myelogenous leukemia in children.

Progress in the treatment of childhood AML has not equalled the advances obtained in the management of ALL. Two recent chemotherapy studies (i.e. VAPA and BFM 78), however, reported marked increase in the proportion of long-term remissions. The initial therapy of the cooperative study BFM 78 consisted of two 4-week phases of intensive induction/consolidation with 7 different drugs and cranial irradiation followed by maintenance with thioguanine and cytosine arabinoside for 2 years and additional adriamycin during the first year. A total of 151 children with AML were enrolled in the study from 30 centers. Of these 119 (79%) patients achieved complete remission. After a median observation time of 34 (14-57) months, there have been 46 relapses. CNS was involved in 6 of these relapses. Life table analyses revealed the following probabilities after 4 1/2 years: survival: 46%; disease-free survival: 41% (total group), 52% (remission group); disease-free interval 56% (remission group). The risk of relapse appears to decrease considerably after 2 1/2 years. No risk factors for the occurrence of relapse have been identified.

Adolescent↗
PubMed1985

Differential pattern of DNA-aneuploidy in human malignancies.

The differential pattern of DNA-aneuploidy, detected by flow cytometry (FCM) regarding its frequency, grade and multiclonality, was investigated and correlated to tumor type, malignancy grade, tumor stage and prognosis in a multi-institutional study at the University of Münster. High resolution measurements using admixed normal blood reference cells were undertaken in 2413 cases of 13 different malignant diseases and in 776 benign lesions or samples. The incidence of DNA-aneuploidy was highest in melanomas, carcinomas, testicular tumors, sarcomas (75%-95%) and myelomas (65%). Acute leukemias showed an intermediate DNA-aneuploidy rate of 40% with special subgroups represented by common ALL (44%), p less than 0.05) and myelomonocytic/monocytic AML (47%, p less than 0.01). The lowest DNA-aneuploidy-rate was found in basal cell skin carcinomas (19%) and congenital melanocytic nevi (9%). No case of DNA-aneuploidy was observed in the 776 benign lesions or samples.--DNA-indices giving the grade of DNA-aneuploidy with 1.0 for normal diploid G1/0 cells were found distributed predominantly between 1.0 and 2.0 in the solid tumors, except testicular tumors, clustering around a triploid maximum at 1.5. DNA-indices of myelomas and acute leukemias generally ranged below 1.25 with lower DNA-aneuploidy grades in AML than in ALL (p less than 0.01).--In melanomas the aneuploidy rate was higher (86%) in metastases than in the primary tumors (54%, p = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Myocardial hemodynamics during induced hypotension: a comparison between sodium nitroprusside and adenosine triphosphate.

Adenosine triphosphate (ATP) has been reported to be a hypotensive agent similar in effect to sodium nitroprusside (SNP). The purpose of this study was to examine and compare the effects of both SNP and ATP on general coronary hemodynamics, myocardial O2 consumption, and circulating catecholamines. Twelve dogs were anesthetized with 1.0% halothane and given either SNP or ATP by controlled infusion to reduce their systemic blood pressure by 50% for a 2-h period followed by a (blood pressure) recovery period. The ATP-induced hypotension was rapid, easily controlled, not accompanied by tachyphylaxis over the 120 min studied, and resulted in an increase in coronary sinus blood flow (CSBF), which plateaued at 260% above control. The increase in CSBF was almost immediate and remained at this elevated level for the duration of the induced hypotension. During the ATP-induced hypotension, there was no change in heart rate or circulating catecholamines. A 60% reduction in myocardial O2 uptake was observed, presumably from the cardiac unloading. In contrast, SNP-induced hypotension required a marked increase in dose over time, did not significantly increase CSBF, did increase heart rate, and resulted in large increases in circulating plasma catecholamines. Neither agent affected cardiac output. ATP-induced hypotension resulted in no change in cardiac lactic acid uptake, while SNP caused lactic acid production, indicating possible cardiac ischemia or cyanide toxicity.

Adenosine Triphosphate↗
PubMed1985

Improved treatment results in childhood acute myelogenous leukemia: a report of the German cooperative study AML-BFM-78.

One hundred fifty-one children with acute myelogenous leukemia (AML) entered the cooperative study BFM-78 between December 1978 and October 1982. The initial therapy consisted of an intensive induction and consolidation regimen over eight weeks with seven different drugs and cranial irradiation. It was followed by maintenance with thioguanine and cytosine arabinoside for two years and additional Adriamycin during the first year. One hundred nineteen (79%) patients achieved a complete remission. Thirteen (9%) children died of early hemorrhages. After a median follow-up time of 36 (12 to 57) months, 47 relapses have occurred, with CNS involvement in seven cases. The life table analysis revealed a probability for overall survival after almost five years of 45% (SD, 4%), for event-free survival 41% (SD, 4%), and for the event-free interval 52% (SD, 5%). Up to now, no relapse was seen after 2 1/2 years. Risk factor analysis showed that early fatal hemorrhages occurred predominantly in children with M5 FAB type and with initial leukocytosis. An initial high WBC count and liver enlargement were unfavorable parameters for achieving remission. No factors could be identified concerning the risk for relapse. These data indicate that the applied treatment strategy is successful in inducing complete remissions in about three fourths of children with AML and also in enhancing considerably the chances for long-term remission.

Adolescent↗
PubMed1985

[Cytological detection of cancer of the cervix uteri].

In spite of the apparent simplicity in detection of dysplasias (cervical intraepithelial neoplasias or CIN I, II, or III) and cancer of the cervix, numerous epidemiologic, biochemical, cytologic and socioeconomic problems are involved. The purpose of this early detection is unquestionably sound, even if the efficiency seems not to achieve high levels in accordance to expectations concerning results and if the cost of reiterated cervical and vaginal scraping smears seems exorbitant. The financial constraints and some cost-effectiveness analyses have promulgated use of longer intervals between cytologic exams (Pap tests). Such an attitude is only acceptable if an improvement in quality and sensitivity of detection is likewise established: other factors such as variable biologic development of epithelial lesions of the cervix must be taken into account; and consideration of cytologic sensitivity of early detection with the difficulties encountered in definition and identification of groups of women at risk. The longer spread between Pap smears exposes some women to the danger of non-detection of certain dysplasias (CIN I, II, or III), rapidly developing carcinomas, and so they lose out on the benefits of an early diagnosis, limited, effective, and less expensive treatment.

Adolescent↗
PubMed1985

Effect of the antioxidant (+)-cyanidanol-3 on H2O2 formation and lipid peroxidation in liver microsomes.

(+)-Cyanidanol-3, a flavonoid with antioxidant properties, leads to an increase of hydrogen peroxide production when added to liver microsomes from untreated and variously pretreated rats. No distinct extra production of hydrogen peroxide was observed in liver microsomes from guinea pig, rabbit and man. The optimal stimulatory concentration was 100 microM; at higher concentrations a lesser degree of stimulation was obtained. Metyrapone inhibited the stimulation process, indicating that cytochrome P-450 function may be involved. Increase of hydrogen peroxide formation occurred at the same (+)-cyanidanol-3 concentrations that were capable to inhibit lipid peroxidation, suggesting that the interference of (+)-cyanidanol-3 with the oxidase function of cytochrome P-450 does not compromise its antioxidative activity towards lipid peroxidation.

Animals↗
PubMed1983

Adjuvant chemotherapy in osteosarcoma - effects of cisplatinum, BCD, and fibroblast interferon in sequential combination with HD-MTX and adriamycin. Preliminary results of the COSS 80 study.

In a cooperative adjuvant chemotherapy study of osteosarcoma (COSS-80), 192 patients were registered from December 1979 to March 1982. Forty-one patients have been excluded from study because of their nonadjuvant situation, therapy-limiting clinical conditions, or inadequate diagnosis. One hundred and fifty-one patients have been randomized to receive either the drug combination bleomycin + cyclophosphamide + dactinomycin (BCD) or cisplatinum (CPL) within a course of sequential multidrug chemotherapy including adriamycin (ADR) and high dose methotrexate (HDMTX). After exclusion of 51 patients with some deviation in history and/or management 100 selected patients were randomized once more to receive in addition or not fibroblast interferon after preoperative chemotherapy and surgical removal of the primary tumor. Patients were stratified for age and sex and for site and extension of tumor as well in both randomizations. Median follow up is now 12 (1-16) months. The expected 2-year disease free survival (DFS) rate of the total doubly randomized group is 78% and of the single randomized group 76%. No difference could be discerned between recombined groups receiving BCD vs CPL or interferon vs no interferon. The effect of preoperative chemotherapy on the tumor was evaluated clinically and by histopathologic grading; 66/85 (78%) patients were judged clinically as responders with pathohistologic verification of this finding in 71% of these cases. No adverse effect arose from delaying definite surgery for preoperative chemotherapy, but initial application of chemotherapy as well as planning, preparing, and performing of the surgical procedure have been facilitated. The majority of patients received some kind of limb-salvage treatment without local recurrences so far. A statistically insignificant but intriguing tendency for a slightly higher incidence of pulmonary metastases after resection as opposed to amputation could be detected. Similar to observations in the previous study COSS-77.

Adult↗
PubMed1983

Combined ultrastructural, histochemical, and autoradiographic study of osteosarcoma after preoperative chemotherapy according to the COSS 80 protocol.

Twelve osteosarcomas treated according to the COSS 80 protocol (preoperative chemotherapy, resection) were studied by light and electron microscopic, histochemical, and autoradiographic methods. Evidence of regressive and necrotic changes was found in many tumor cells, but the alterations were unspecific. Viable tumor cells of high malignancy were also observed regularly, often at the S phase. As the tumor regression continued, a strong reaction of the mononuclear phagocyte system was manifested by the presence of macrophages and giant cells.

Acid Phosphatase↗
PubMed1983

Pharmacokinetics of caffeine during and after pregnancy.

The pharmacokinetic parameters of caffeine were measured in 9 pregnant women and 4 women 4 days post partum. The results show a significant prolongation of caffeine elimination in pregnant women. Normal pharmacokinetic parameters seem to be restored as soon as 4 days post partum. Steroids hormones (estriol, estradiol, and progesterone) were measured in both cases.

Adult↗