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Biomedical subjects

M Friedrich

Publications and source records attributed to M Friedrich.

At least 325 records · Page 18Linked to original sources

Heat production and oxygen consumption of the isolated rabbit heart: their relation to mechanical function.

A method is described for simultaneous determination of the heat production and the oxygen consumption of the isolated, isovolumetrically beating rabbit heart. The perfusion of the heart was performed via the aorta at a constant flow rate with carbogen saturated Tyrode's solution at a temperature of 37.0 degrees C. Heart function was varied by stepwise augmentation of the left intraventricular volume (LVV) by means of a balloon catheter. The following mechanical parameter of heart function were determined: enddiastolic pressure (EDP), peak pressure (PP), developed pressure (DP), max. contraction and relaxation velocity (dP/dt-A and dP/dt-B), enddiastolic tension (Tens-EDP), peak tension (Tens-PP), developed tension (Tens-DP), and circumferential tension (Tens-Cir). DP, dP/dt-A and dP/dt-R showed a maximum response to changes of the LVV at 2.0 ml LVV and 19.3 mm Hg EDP. Heat production (H) and oxygen consumption (Q) were correlated closely to mechanical function and to each other (r = 0.89, n = 8). The ratio H/Q was 4.9 cal/ml O2 and remained constant during the experiment. The myocardial energy consumption was significantly correlated toall contraction parameters with the best fit to DP and Tens-Cir (r = 0.934 and 0.933 resp.). On the basis of the calculated mean regression lines, the function-independent and the function-dependent energy consumption were calculated.

Animals↗

[Pain patterns of disc lesions of the lumbar spine].

AIM: The aim of this study was to find out the reliability of several dermatomic maps (description of pain pattern within a nerve root lesion) according to the respective segmental area. METHODS: Different studies which deal with pain pattern caused by disc lesions were searched for with MedLine support and then reviewed. RESULTS: A clear correlation between the pain projections of the lumbar spine does not seem to exist. A contradiction of the most common pain projection (S1) and operated disc (L4/5) is described. CONCLUSION: Even though there are studies of high scientific design and value (Nitta H, Wolff A) the pain pattern of dermatomic maps is only of limited value for the definition of the affected segment.

Diagnosis, Differential↗

Protein supplementation of human milk for the nutrition of VLBW-infants: human milk protein vs. meat protein hydrolysate.

In 25 very low birth weight infants appropriate for gestational age the influences of different human milk (HM) preparations on weight gain, gross indices of nitrogen metabolism and energy balance were studied during the second month of postnatal life. HM was fortified either by HM-protein (HMP) or by an enzymatic meat protein hydrolysate (PH) to protein concentrations between 1.5 and 1.7 g/100 ml. The caloric densities of both HM preparations were similar between 62 and 68 kcal/100 ml. There were no differences in weight gain (MM + HMP: 18.6 +/- 3.4 g/kg/day; HM + PH: 16.5 +/- 4.1 g/kg/day), nitrogen retention (HM + HMP: 31.5 +/- 3.1 mmol/kg/day; HM + PH: 30.0 +/- 3.2 mmol/kg/day), and the preprandial estimated essential amino acid profiles between the both feeding groups. In contrast the serum concentrations of alpha-amino-nitrogen 60 minutes postprandially were elevated in the infants fed HM + PH in comparison to the infants fed HM + HMP. This high postprandial amino acid concentrations in serum in the group fed HM + PH were accompanied by increased bile acids concentrations in serum, higher renal amino acid excretion and increased fecal fat losses. The results suggest that due to the more rapid intestinal absorption of amino acids from PH than from HMP the concentrations of amino acids increase postprandially which results in a detectable increase of the newborn cholestasis in these infants. Nevertheless, the scale of these metabolic responses to feeding protein hydrolysates is small and without detectable influences on nitrogen retention or weight gain.

Amino Acids, Essential↗

[Fundus-oriented perimetry. Evaluation of a new visual field examination method for detecting angioscotoma].

BACKGROUND: Conventional automated perimeters usually work with a given set of grids and thus are normally not adapted to individual conditions. This fact restricts efficiency of this method not only for any single examination but also for follow-up studies. MATERIALS AND METHODS: A new method (patent pending) is introduced which superimposes an individual perimetric grid--corrected in respect to orientation, position and size--onto a patient's fundus image. A recently developed software realizes this procedure in a comfortable manner: the digitized fundus image is loaded into the computer by e.g. photo-CD or disc, depicted on a control monitor and mirrored if necessary. Assuming a central fixation, the foveola is translationally shifted to the center of the perimetric grid by the help of a crosshair. The blind spot which has been previously determined with kinetic perimetry is then superimposed onto the optic disc of the fundus image using a rotation and zoom function. In this way, it is possible to adapt the perimetric grid directly to the underlying individual fundus findings: thus, stimuli can be spatially concentrated or more frequently tested in special regions of interest. Additionally, test points can be dragged away from delicate positions to avoid artifacts. Examinations were carried out on a high resolution colour VDU of the Tübingen Electronic Campimeter (TCC). Alternatively, suited bowl perimeters can be used. RESULTS: In order to test the precision of the superimposing procedure, fundus oriented perimetry was performed to detect angioscotomata in 13 ophthalmologically normal subjects. Using dark stimuli (12'), visual field defects in the expected region, caused by retinal vessels, could be detected in 7 cases (= 54%). The resulting attenuation of differential light sensitivity in this circumscribed region was up to 12 dB. CONCLUSIONS: By means of a morphologically adapted, individual arrangement of stimulus locations fundus-oriented perimetry enables detection of even minute (angio-) scotomata.

Adult↗

[Current aspects in the diagnosis of spondylodiscitis].

New aspects regarding the diagnosis of spondylodiscitis are shown by means of the casuistics of a severe immobilizing lumbar syndrome. In this special case only the MR-examination was able to make clear the diagnosis, at a time when all other diagnostic methods failed. The MR-examination was taken as primary and progressive diagnostic method and it also decided about therapeutic consequences.

Adult↗

[Effect of patient age on use of the knee joint score].

AIM OF THE STUDY: Clinical studies are done with the help of scores though different factors of influence lower comparability. The underlying study examines the influence of patient age as this always presents a certain span. METHOD: 96 degree I damaged knee joints were examined by 3 examiners using the Larson-, Lysholm-, Marshall-, HSS- and OAK-score. Furthermore ratings by a VAS and the Tegner activity score were done. With the Friedman test, the rank correlation coefficient by Spearman and the contingency chart by Bowker it was tested if the examiners and the scores rate equally. To find out the influence of the age three age groups were made up. RESULTS: The examiners judged significantly different excluding the Marshall and the OAK scores. In between two examiners no significant difference could be found between the young and the middle-aged patient group. Between two other examiners no significant difference was found only for the Lysholm and the HSS score in the young group and only for the Lysholm score in the middle-aged group. In the group of the senior patients no significant difference for the scores by Lysholm, Marshall and OAK were found. In the comparison of the second examiner pair no significant differences could be proven by the scores by Larson, the OAK and the HSS. All other comparisons were significantly different. In the comparison of all five scores significant differences were seen between the Larson score and the HSS and the Lysholm and the HSS. The Lysholm score proved to be the strictest, the HSS to be the leanest. CONCLUSION: Especially for the senior patients in dependency of the examiner and the chosen score significant differences were found concluding that the relevance of results lessens for future times as the score results drop with patient age anyway. The age span in one study should have a maximum of 10-20 years to reduce the influence of age on the final result.

Activities of Daily Living↗

Changes in plasmatic biochemical parameters during experimental murine paracoccidioidomycosis.

Determinations of plasma cholesterol, HDL-cholesterol, triglycerides, total proteins, bilirubin, aspartate transaminases (AST), glucose, iron and total iron binding capacity were evaluated after 15 and 90 days of intraperitoneal infection with 5 x 10(6) virulent yeasts of Paracoccidioides brasiliensis Pb 18 isolate in resistant (A/J) and susceptible (B10.A) mice. Significant differences between control and infected groups were seen: an increase of triglycerides and total proteins for both strains, a decrease of glucose and HDL-cholesterol in B10.A mice and of iron in both strains, while AST, bilirubin and TIBC increased only in B10.A mice. While glucose, AST, bilirubin and TIBC were strongly modified in susceptible mice, no differences were seen in the resistant infected group, thus confirming the usefulness of biochemical parameters as an index of infection severity, as well as of recovery.

Animals↗

[The dose dependence of 15N-incorporation in organ proteins of newborn rats after pulse labeling with different tracers].

A short-chain 15N-peptide mixture characterized by an average chain length of 2.3 was obtained when 15N-labeled yeast protein has hydrolyzed enzymatically by thermitase from Thermoactinomyces vulgaris. Fifteen newborn Wistar-rats were given a single pulse of [15N]glycine. [15N]H4Cl and [15N]yeast protein-thermitasehydrolysate (YPTH) in a dosage of 50 mg 15N excess kg-1 by gastric tube. In comparison with [15N]glycine the 15N-incorporation rates of brain, muscle and liver were approximately 150% higher after [15N]YPTH-application. Uniform labeling, high 15N-enrichment, almost complete absorption, avoidance of imbalances and the low price make this tracer substance superior to other tracers conventionally used for organ labeling.

Animals↗

Prenatal and perinatal aspects of a giant fetal cervicothoracal lymphangioma.

A massive cervicothoracal lymphangioma was diagnosed in a fetus at 25 weeks of gestation. On ultrasound study, the mass showed septated, cystic components and extended from the right submandibular region to the right anterolateral thoracic wall including the right axilla and right scapula. Close sonographic follow-up revealed an increase in the size of the lymphangioma without fetal hydrops. An interdisciplinary approach including a pediatric surgeon, neonatologist, perinatologist and anesthesiologist was chosen. Elective cesarean section under general anesthesia was planned at 37 + 0 weeks of gestation. Surgical correction of the lymphangioma was successfully performed on the 4th day of life. Possible differential diagnoses and the obstetrical management are presented.

Adult↗

Immunohistochemical analysis of DNA mismatch-repair enzyme hMSH-2 and Ki-67 in breast carcinomas.

BACKGROUND: The human Mut-S-Homologon-2 (hMSH-2) gene product is a member of a highly conserved family of proteins involved in postrepiclation mismatch repair. MATERIALS AND METHODS: We have analyzed hMSH-2 expression in normal breast tissue (n = 10) and breast carcinomas (n = 30). hMSH-2 protein was investigated immunohistochemically on frozen sections using a specific mouse monoclonal antibody (clone FE11). hMSH-2 labelling pattern was compared with the staining pattern of the proliferation marker Ki-67. A hMSH-2-immunoreactivity score (hMSH-2-IRS) for the semiquantitative analysis of hMSH-2 expression is presented. RESULTS: In normal breast tissue, we only found weak nuclear immunoreactivity for hMSH-2 in 70%, while the remaining 30% were hMSH-2 negative (mean hMSH-2- IRS: 1.00; SD: +/- 0.82). All breast carcinomas analyzed revealed moderate to strong nuclear immunoreactivity (mean hMSH-2-IRS: 7.67; SD: +/- 3.55). hMSH-2 staining was heterogeneous, with visual differences between individual tumour cells. Expression of hMSH-2 protein was consistently and strongly upregulated in tumour cells of breast carcinomas as compared to normal breast tissue. No visual correlation in comparing the labelling patterns for hMSH-2 with the labeliing patterns for Ki-67 (mean percentage of Ki-67 positive tumour cells: 24.33%; SD: +/- 15.35) was observed in breast carcinomas. CONCLUSION: Our findings indicate that (a) hMSH-2 is expressed in normal human breast tissue; (b) expression of hMSH-2 may be of importance for the genetic stability of breast carcinomas in vivo.

Base Pair Mismatch↗

Treatment of metastatic hormone-refractory prostate adenocarcinoma (MatLyLu) in Copenhagen rats with micro-osmotic interleukin-2 pumps.

BACKGROUND: We studied the influence of interleukin-2 (IL-2) therapy on tumor growth and prevention of metastasis in metastatic, hormone-refractory prostatic carcinoma (PCa) in an animal model orthotopically (ortho) and subcutaneously (s.c.). MATERIALS AND METHODS: 75 juvenile male Copenhagen rats were divided into five groups of 15 rats each. MatLyLu-PCa (MLL) was implanted ortho (n = 30) in 2 groups or s.c. (n = 30) in 2 groups and were treated locally at the tumor site with micro-osmotic pumps. The rats in 2 groups received IL-2 pumps with 36 x 10(6) IU of IL-2 and the rats in 2 other groups were treated with pumps delivering albumin only as a control. The rats in the last group received ortho MLL and s.c. IL-2 (n = 15). Survival time was then monitored. RESULTS: Prostatic tumor was found in all ortho animals. Additionally lymphogenic and pulmonary metastasis was found in all animals. The orthotopic and s.c. IL-2-treated groups showed a statistically significantly increased survival compared with the orthotopic and s.c. albumin-treated groups. When treating the ortho MLL with s.c. IL-2 there was still a statistically significant longer survival than in the control groups. CONCLUSION: IL-2 therapy significantly reduces tumor growth of rats with metastatic, hormone-refractory prostatic cancer MatLyLu.

Adenocarcinoma↗

Endometrial stromal sarcomas--a retrospective analysis of 11 patients.

BACKGROUND: Endometrial stromal sarcoma (ESS) is a malignant tumour with its origin in the endometrial stroma. Little is known about the pathogenesis, risk factors, optimal therapy or outcome of this disease. PATIENTS AND METHODS: Eleven patients with ESS, treated between 1972 and 1996, are reported on. The hospital records of all the patients, including pathology and operative reports, were reviewed and information on treatment, recurrence and survival was obtained. RESULTS: The mean age of our patients was 56.6 years. The main symptom was abnormal vaginal bleeding. Most patients were diagnosed at FIGO stage I. Treatment modalities were surgery, radiation and, in one patient, chemotherapy. The median follow-up time was 42.1 months; 27.3% of the patients had local recurrence. The 1-year, 2-year and 5-year survival rates were 36.3%, 18.1% and 9.1%, respectively. CONCLUSION: ESS is a uterine sarcoma with a difficult differential diagnosis. Patients are frequently diagnosed in an early tumour stage but still experience local or distant recurrence. The prognosis is poor, with early recurrence and low long-time survival rates. The treatment includes surgery and adjuvant radiation, with endocrine therapy being a promising new approach. In order to obtain more information about the pathogenesis of the tumour and to find the optimal therapy, it is necessary that studies, even with small numbers of patients, are undertaken.

Adult↗

Modulation of MAPK ERK1 and ERK2 in VDR-positive and -negative breast cancer cell lines.

1alpha-25-Dihydroxyvitamin D3 (calcitriol), the biologically active metabolite of vitamin D, is known to regulate calcium and phosphate levels in bone metabolism. It is also known to influence proliferation and differentiation in carcinoma cells mediated by the vitamin D receptor (VDR). The antiproliferative effects of calcitriol are believed to be mediated by the nuclear pathway via binding the activated receptor to vitamin D-responsive elements. This induces the vitamin D-responsive genes. Another possible pathway might be the MAPK-cascade or rapid response pathway. The interaction of calcitriol and the MAP-kinase-cascade was evaluated on VDR-positive MCF-7 cells and VDR-negative MDA-MB-231 breast cancer cells. The cells were incubated with calcitriol solution at 10(-7) M and 10(-9) M, or ethanol as controls, for up to 48 h. The effects of calcitriol were measured by semi-quantitative Western blotting. Calcitriol stimulated the MAP-kinases ERK1 and ERK2. A biphasic activation was found for calcitriol in VDR-positive cells after incubation for 5 to 20 min and from 2 to 24 h. However, early activation of ERK1 and ERK2 was also demonstrated in VDR-negative cells. In the controls, ethanol also induced the MAPK-cascade at 5 to 10 min. Calcitriol induction was demonstrated after incubation from 2 to 24 h. In conclusion, it seems that the early induction of the MAPK-cascade was independent of the VDR. A calcitriol-induced MAPK activation was shown after 4 h, which may have been caused by activation of the nuclear receptor pathway.

Breast Neoplasms↗

Carcinosarcomas--a retrospective analysis of 21 patients.

BACKGROUND: Carcinosarcomas (CS) are mixed epithelial and stromal tumours with both components being malignant. Twenty-one patients with carcinosarcomas who were treated at the University of Saarland, Germany, are presented. PATIENTS AND METHODS: The hospital records of all patients were reviewed. RESULTS: The mean age range for homologue CS (homCS) was 60.7 years and for heterologue CS (hetCS) 68.4 years. Post-menopausal bleeding and abdominal pain were the main symptoms. Treatment modalities included surgery, adjuvant radiation therapy and various chemotherapy regimens. The median follow-up time was 17.6 months (homCS) and 31.1 months (hetCS). The 1-year survival rate was 55.6% (hetCS 58.3%) and the 5-year survival rate was 11.1% (hetCS 8.3%). CONCLUSION: Carcinosarcoma is a uterine sarcoma with a poor prognosis. Treatment includes surgery and adjuvant chemotherapy, whereas radiotherapy does not necessarily lead to a benefit. Treatment with trastuzumab might be a new approach in the therapy of HER-2/neu-positive CS.

Aged↗