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Biomedical subjects

R Langer

Publications and source records attributed to R Langer.

At least 469 records · Page 26Linked to original sources
PubMed1988

[Ultrasound findings in patients with AIDS].

The ultrasonographic findings of 43 patients with AIDS and ARC were analyzed. In 63% an enlarged liver, in 66% an enlarged spleen, partially with focal lesions, and in 21% enlarged abdominal lymph nodes were diagnosed. The typical parenchymal lesions of the kidney (focal segmental glomerulosclerosis) were not observed. Abdominal ultrasound is the first diagnostic procedure to perform in patients with AIDS and ARC with the suspicion of abdominal pathology. With additional thin needle puncture of the lesions a histological verification of the pathologic findings is possible.

AIDS-Related Complex↗
PubMed1988

Influence of pentoxifylline administered in vivo on the synthesis of PGI2 in human varicose veins.

The influence of pentoxifylline on the synthesis of prostacyclin (PGI2) was studied using human varicose veins removed by a stripping operation. Patients got 100 mg pentoxifylline iv. during the operation. The synthesis of PGI2 was studied according to the inhibition of the ADP-induced platelet aggregation without and with addition of substrate (100 ng prostaglandinendoperoxide H2) to the incubation fluid. There were no changes in the synthesis of PGI2 compared to control values.

Epoprostenol↗
PubMed1988

[Digital radiographic image enhancement in bone diagnosis--initial clinical results].

34 patients with skeletal alterations mostly in the periphery were investigated by digital image intensifier radiography (DIIR). A high resolution image-intensifier system (1024 x 1024 matrix, 40 cm, 28 cm, 14 cm image intensifier, maximal spatial resolution: 3.6 lp/mm) was available. The image quality was diagnostic sufficient in 76% using DIIR. A good or very good image quality of fine-structures was obtained only in 41%. The quality deficits in comparison to conventional radiograms were particularly obvious in investigation of the phalangeals. Logarithmic amplification and software upgrading lead after these first clinical investigations to a better image quality.

Adult↗
PubMed1988

Ovarian residual syndrome.

During the years 1979 to 1983, 329 patients underwent hysterectomy with preservation of one or both ovaries. Six patients were evaluated for postoperative chronic lower abdominal pain and dyspareunia. Findings at laparotomy confirmed the diagnosis of residual ovarian syndrome in all six. Relief of symptoms was observed after adnexectomy in four, oophorectomy in one patient and ovariopexy in one. The literature concerning this rare complication after hysterectomy is briefly reviewed.

Abdomen↗
PubMed1987

[Early systemic thrombolysis in acute myocardial infarct. Comparison between the clinical and the prehospital phase].

Short-term systemic thrombolytic treatment was undertaken in 84 patients--within the first three hours after onset of pain; with typical ECG signs of acute transmural myocardial infarction; refractory to nitroglycerin--either in an intensive care unit (n = 40) or in a medically-staffed ambulance (n = 44). Coronary angiography was undertaken in patients of both groups, after obtaining informed consent, at the earliest possible moments, combined with percutaneous transluminal coronary angioplasty (PTCA), if indicated. Thrombolytic treatment in the ambulance was primarily more effective (72%, n = 32) than in the ICU patients (47.5%; n = 19), and the pain-thrombolysis interval shorter by 30 min. The higher recurrent infarction rate in the former meant that the success rate at the end of the hospital stay did not significantly differ between the two groups (54.5% and 47.5%, respectively). Only when early systemic thrombolysis was combined with PTCA within the first three hours (n = 26) was there a markedly greater effectiveness after four weeks (77%) than without PTCA (40%). Early thrombolytic treatment by doctors in the ambulance during transfer to hospital is sensible only if it can be followed at once by coronary angiography with PTCA or operation soon after admission. Only in this way will the effectiveness of treatment be increased and maintained after discharge from hospital.

Acute Disease↗
PubMed1987

In vitro and in vivo kinetics of regulated drug release from polymer matrices by oscillating magnetic fields.

The kinetics of drug release from polymer-drug matrices containing an embedded magnet was continuously monitored in vitro and in vivo. The application of an oscillating magnetic field increased the rate of drug release from the polymer matrices. Within the limits of detection the increase in release occurred immediately, remained stable for as long as the field was applied, and returned exactly to baseline upon withdrawal of the field. The increase in release was directly proportional to field amplitude. The same pattern of results were observed in vivo as in vitro, though higher strength fields were required in vivo to achieve the same effect observed in vitro.

Animals↗
PubMed1987

Controlled release using a new bioerodible polyphosphazene matrix system.

Polyphosphazenes possess polymer backbones consisting of nitrogen and phosphorous formally separated by alternating single and double bonds. Their potential for biomedical applications stems from the fact that polymers with a wide array of properties can be synthesized using the same starting compound, poly(dichlorophosphazene), through changes in side chain substituents, and that many of these compounds synthesized have been found to biodegrade to harmless products. In this article, studies of a novel monolithic bioerodible polyphosphazene matrix system for controlled drug delivery are presented. Poly(imidazole methylphenoxy)phosphazene is synthesized and shown to be bioerodible. The versatility of drug delivery devices fabricated using this polymer is shown through studies of release of macro-molecules and low molecular weight drugs. Initial histological evaluations of this particular polyphosphazene are also presented.

Aniline Compounds↗
PubMed1987

Magnetically enhanced insulin release in diabetic rats.

Polymer matrices containing insulin and embedded magnets were implanted subcutaneously in diabetic rats for 51 days. Passive release of insulin from the polymer resulted in a decrease in the blood glucose level. When the diabetic rats were exposed to an oscillating magnetic field, the blood glucose levels were additionally lowered by nearly 30%. No statistically significant effect in blood glucose decrease was observed in four different sets of control animals subjected to the magnetic field. Because of the very small size of the implants, they may, with additional study, provide an alternative to current modes of therapy using programmable implantable infusion pumps.

Animals↗
PubMed1987

Ultrasonic investigation of the hip in newborns in the diagnosis of congenital hip dislocation: classification and results of a screening program.

The method of ultrasonic examination of the hip is described, the latest updated Graf classification is explained, and the results of a prospective screening program are described. One thousand four hundred and sixty newborn infants were examined by ultrasound and clinically by independent observers. The distribution of the ultrasound types was determined. Recommendations are given for the use of ultrasonic investigation of the hip for groups at risk in the neonatal period.

Female↗
PubMed1987

Arteriovenous malformation of the great cerebral vein (of Galen) in a newborn. Diagnosis by ultrasound and digital subtraction angiography.

This is a report of a case with an arteriovenous (a.v.) malformation of the great cerebral vein. Applicable diagnostic procedures are reviewed. The initial diagnostic procedure in the approach to an a.v. malformation of the great vein of Galen is cerebral ultrasound. The findings in our patient are compared with those reported in the literature.

Cerebral Angiography↗
PubMed1987

Reproductive outcome after fimbrial evacuation of tubal pregnancy.

Thirty-one ectopic pregnancies were manually expressed (i.e., "milked out") by the tubal fimbria during a 13-year period. Reproductive histories and operative findings were unremarkable when compared with the general population with ectopic gestation. The subsequent reproductive performance was evaluated in 27 patients who attempted conception. Twenty-five (92%) of the 27 patients subsequently conceived, 23 (85%) had at least one successful term pregnancy, and the remaining 2 (7%) had abortions only. There was no repeat ectopic pregnancy. Average follow-up time was 38.5 months. Previous experience with this technique has been disappointing with low postoperative rates of successful term pregnancies. Favorable outcomes after fimbrial expression have been reported only in small numbers of patients. It is suggested that the procedure is appropriate for distal tubal gestations that are loosely adherent within the tubal lumen; these are usually expressed with minimal efforts. However, if the gestational mass does not yield to gentle milking of the tube or evacuation has been incomplete, the surgeon can always use a linear salpingotomy. More experience is obviously needed to verify these preliminary results, suggesting that fimbrial evacuation is simple, safe, and advantageous in properly selected cases.

Adult↗
PubMed1987

Extracorporeal enzymatic heparin removal: use in a sheep dialysis model.

Extracorporeal medical devices such as the hemodialyzer rely on systemic heparinization to prevent thrombus formation. Heparin, however, can lead to serious hemorrhagic complications. A blood filter containing immobilized heparinase, a heparin specific enzyme, was used to degrade heparin into small fragments which have significantly less anticoagulant activity than the parent compound. The heparinase filter was tested in the extracorporeal circuit during the hemodialysis of adult sheep. At a blood flow of 200 ml/min, the clearance of heparin varied from 50 to 70 ml/min (N = 16) depending on the amount of immobilized heparinase in the filter. Hemolysis was insignificant as measured by the animals' red cell counts, hematocrit, total hemoglobin and a plasma-free hemoglobin value of 89 +/- 33 mg/dl (N = 16) (less than 1% of the total hemoglobin). The white cell counts dropped to 47 +/- 7% (N = 16) of the initial value at 20 minutes and rebounded to 72 +/- 10% (N = 16) after one hour. The platelet counts decreased to 55 +/- 8% (N = 16) of the initial value after one hour. No change in heparin clearance was observed when reactors were used repeatedly in adult sheep over a 10 week period. The red cell counts, white cell counts, platelet counts, total hemoglobin and hematocrit did not change after 10 weeks of exposure to the device. These results suggest that with further study, heparinase may be useful in removing heparin used to anticoagulate blood in extracorporeal circuits.

Animals↗
PubMed1987

[Sonography of the hip joint in skeletal dysplasias and chromosome disorders].

The preliminary results of ultrasound of the hip in patients with skeletal dysplasias and chromosomal aberrations are described. Pathology of the hip joint can be demonstrated by ultrasound; especially the entities with abundant cartilage can be visualized by sonography. Ultrasound of the hip is a valuable method in the diagnosis of skeletal dysplasias complementary to plain x-ray surveys.

Bone Diseases, Developmental↗
PubMed1987

Fertility following conservative surgery for tubal pregnancy.

Eighty seven conservative surgical interventions for unruptured tubal pregnancy were performed on 83 patients. Salpingotomy was performed in 66 cases and expression of tubal pregnancy in 21 cases. In this patient group, 76.7% (56 out of 73) experienced intra-uterine pregnancy following surgery and 71.2% (52 out of 73) had a live birth. The recurrence rate of tubal pregnancy was 12.3%. Of the 42 patients with a normal contralateral tube, 36 (85.7%) had an intra-uterine pregnancy, 80.9% had a live birth and 7.1% had a recurrent tubal pregnancy. Sixty percent of the patients who underwent operation on their single tube, had a live birth and 66.6% had an intra-uterine pregnancy; the recurrence of tubal pregnancy in this group was 26.6%. No recurrence of tubal pregnancy was found in the group of patients who underwent expression of tubal gestation. It is suggested that the expression of tubal gestation (milking) is a safe procedure for conserving future fertility, and that the indications for conservative surgical management in patients with unruptured tubal gestation should be broadened to include all patients interested in future pregnancies, regardless of the current state of the contralateral tube.

Adolescent↗