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Biomedical subjects

J Kirchner

Publications and source records attributed to J Kirchner.

At least 73 records · Page 4Linked to original sources
PubMed1997

Balloon dacryocystoplasty: indications and contraindications.

PURPOSE: To define the indications and contraindications for balloon dacryocystoplasty. MATERIALS AND METHODS: Eighty-five patients with severe epiphora due to partial (n = 47) or complete (n = 38) obstruction of the nasolacrimal duct (NLD) were treated with balloon dacryocystoplasty (DCP). Steerable micro-guide wires with flexible tips were used. Success rates of DCP were evaluated clinically and dacryocystographically during the acute phase and at 6- and 12-month follow-up. Failures and recurrences were correlated with clinical and dacryocystographic indications for treatment. RESULTS: Recanalization was successful in 35 (92%) of 38 patients with isolated focal stenoses (n = 20) or short-distance occlusions (n = 18) of the NLD. Among all 85 patients, recanalization was successful in 25 patients (66%) with complete and 37 patients (79%) with partial obstructions. In the absence of the main predictors for recurrent obstructions (ie, active inflammation, filling defects due to calculi, long-distance occlusions, and posttraumatic lesions), 12-month patency rates were 89% (17 of 19 focal stenoses) and 94% (15 of 16 focal occlusions). Otherwise, reobstruction rate was 46% (12 of 26 cases). CONCLUSION: Balloon dacryocystoplasty is successful only in select cases. To achieve results comparable to those of operative treatment, the indication should be limited to patients with circumscribed focal stenoses or occlusions of the NLD. Active dacryocystitis, dacryocystolithiasis, and posttraumatic lesions are the main contraindications.

Catheterization↗
PubMed1997

[Teratoma of the mediastinum--detection in conventional imaging and CT].

We report the case of a 20-years old female patient with a tumor in the anterior mediastinum which was coincidently detected by a conventional X-ray of the chest. Differential diagnose were eliminated was constructed by means of computed tomography showing area of fatty density. The tumor was exstirpated because of its possible malignancy as well as the possibility of the development of local complications. Histology confirmed the tentative diagnosis of fatty cystic teratoma.

Adipose Tissue↗
PubMed1997

[MRI: incidence and evaluation of size and form criteria in hypophysis-healthy probands and in patients with detectable microadenomas].

Magnetic resonance imaging (MRI) was performed in 42 patients with proven microadenomas and in 42 patients with normal pituitary hormone analysis. The normal MRI--anatomy of the pituitary gland and its possible variations with measurement of the volume and comparison of the anatomy with that of the gland after changes caused by microadenomas has to our knowledge not yet described. In this study we measured the height, coronary and sagittal diameter of the pituitary gland in both groups as well as other indirect signs of microadenomas (asymmetry of the gland, sella turcica, and the stalk). The pituitary volume indicates the expansion of microadenomas much better than the gland height (and the other diameters). Normal pituitary glands showed a significant lower volume (525 +/- 137 mm3 [R = 225-800 mm3]) than patients with proven microadenomas (734 +/- 393 mm3 [R = 335-2800 mm3], p < 0.001). The normal pituitary gland and sella turcica show a large variety of anatomic variations. These variations are less frequent in healthy subjects (10-21%) than in patients with microadenomas (48-71%). The described criteria are of some value in diagnosis of a suspected gland hypertrophy or microadenoma. In 75% of the patients with normal pituitary parameters and in 12% of the patients with microadenomas no indirect adenoma criteria was found in our study.

Adenoma↗
PubMed1997

[Radiologic appearance of primary anomalies of the lymphatic vessel system of the lung. Review and personal results].

Congenital disorders of the lymphatics of the lung are rare. On the basis of a literature review and our own experiences the disorders are divided into four groups and their radiographic findings are described. Pulmonary lymphangiectasia shows not typical signs. As an expression of the underlying pathophysiologic processes CT shows thickening of interlobular septs, interstitial edema and pleural effusions. Neither architectural distraction nor thickening of intralobular septs was seen. Lymphangioleiomyomatosis shows rather typical findings with multiple thin-walled bullae. In contrast to the opinion that architectural distraction is not seen in LAM we sometimes found signs of fibrosis. Disseminated pulmonary lymphangioma is characterised by proliferation of lymph vessels. CT-findings of this disorder have not been described before. CT shows multiple disseminated nodules of up to 2.5 cm accompanied by multiple bullae of similar distribution and size.

Humans↗
PubMed1997

[Preoperative radiotherapy for prevention of heterotopic ossifications after hip endoprosthesis].

Preliminary results of a prospective study which investigates the efficacy of preoperative radiotherapy (RT) for prevention of heterotopic ossification (HO) after total hip arthroplasty are summarized. A total number of 20 hip joints (18 patients) were irradiated with a single dose of 6.0 Gy < 4 hours before the surgical procedure. After an average observation period of 6.9 months (range: 6-11 months) the results were evaluated using radiological and clinical criteria. At follow-up, one case (5%) had evidence of high-grade HO (> Brooker grade II). The functional outcome quantified with the Harris score was improved by an average of 37.9 points. The authors conclude that preoperative RT is an effective alternative for postoperative irradiation.

Adult↗
PubMed1997

[Hamman-Rich syndrome in a goldsmith].

We report the case of a 54-year old goldsmith admitted because of dyspnea on exertion, persistent cough, and weakness under the suspicion of exogenous allergic alveolitis. He rapidly developed progressive lung fibrosis with exitus letalis 7 weeks after admission. Radiological examination (chest X-ray and HRCT) first showed ground glass opacties, and later rapid development of severe interstitial pattern with architectural distraction. The findings were similar to idiopathic lung fibrosis; however, the rare Hamman-Rich syndrome was confirmed by progressive course of the disease. Correlations between Hamman-Rich syndrome and idiopathic lung fibrosis are discussed.

Diagnosis, Differential↗
PubMed1997

Sonographic detection of focal changes in the liver hilus in patients receiving corticosteroid therapy.

OBJECTIVE: While diffuse deposition of fat may occur with corticosteroid (CS) administration both in the liver and in other organs, comparatively little is known about focal changes in the liver under corticosteroid medication. Therefore, we evaluated pattern and extent of focal hepatic steatosis by ultrasound (US) in patients receiving corticosteroids. SUBJECTS AND METHODS: 93 patients with known inflammatory bowel disease (IBD) received corticosteroids during a period of at least six weeks prior to the ultrasound examination and 28 IBD-patients had no corticosteroids within the last three years. 13 additional patients received corticosteroids for other reasons than IBD for > 1 year. 80 healthy volunteers served as controls. Focal changes of the liver as assessed by high resolution ultrasound (Acuson 128, 3.5 and 5 MHz) were defined as areas of brighter echogenicity compared to the general aspect of the liver. The size of the hyperechoic areas was documented (photoprint). RESULTS: 40/93 IBD-patients with corticosteroids (43%) had definite areas of brighter echos in the hilus region of the liver. In IBD-patients without corticosteroids only one patient showed a focal brighter echogenicity, whereas in the non-IBD group with corticosteroids 8/13 had focal lesions (62%). In the control group only four healthy subjects showed brighter areas (5%). CONCLUSION: Bright focal areas in the liver hilus occur in > 40% of IBD-patients during corticosteroid medication. This phenomenon occurs in IBD-patients as frequently and as intense as in other patients with longstanding corticosteroid therapy. There is a hilar area of the liver with typical size and location which reacts to corticosteroid administration with hyperechoic reflexes at ultrasound investigation. This is important to know when it comes to the differential diagnosis of focal changes.

Adrenal Cortex Hormones↗
PubMed1996

Multiple potential germ-line helicases are components of the germ-line-specific P granules of Caenorhabditis elegans.

Two components of the germ-line-specific P granules of the nematode Caenorhabditis elgans have been identified using polyclonal antibodies specific for each. Both components are putative germ-line RNA helicases (GLHs) that contain CCHC zinc fingers of the type found in the RNA-binding nucleocapsid proteins of retroviruses. The predicted GLH-1 protein has four CCHC fingers; GLH-2 has six. Both GLH proteins localize in the P granules at all stage of germ-line development. However, the two glh genes display different patterns of RNA and protein accumulation in the germ lines of hermaphrodites and males. Injection of antisense glh-1 or glh-2 RNA into wild-type worms causes some offspring to develop into sterile adults, suggesting that either or both genes are required for normal germ-line development. As these very similar glh genes physically map within several hundred kilobases of one another, it seems likely that they represent a fairly recent gene duplication event.

Amino Acid Sequence↗
PubMed1996

[Disseminated pneumoperitoneum during the therapy of lymphoma with methotrexate and cytosine arabinoside].

HISTORY AND CLINICAL FINDINGS: A 58-year-old man was treated for abdominal and inguinal recurrence of a centroblastic non-Hodgkin lymphoma with high doses of methotrexate and cytosine arabinoside. A chest radiogram, taken on the 18th day of chemotherapy to exclude pulmonary infiltration, revealed pneumoperitoneum. The patients's complaints were merely of abdominal fullness and persisting diarrhoea. His general state was hardly impaired, the abdomen soft on palpation with active peristalsis. INVESTIGATIONS: There was aplastic anaemia (haemoglobin 9.9 g/dl, erythrocytes 3.4 x 10(6)/microliters, white cells 1000/microliters, platelets 20,000/microliters. Plain film of the abdomen and abdominal computed tomography confirmed pneumoperitoneum. Intraluminal air had caused wall dissection in the ascending and transverse colon (pneumatosis coli as cause of the pneumoperitoneum). TREATMENT AND COURSE: There was complete absorption of the free abdominal air by the 29th day of chemotherapy under parenteral nutrition and metronidazole (3 x 500 mg daily).

Anemia, Aplastic↗
PubMed1996

[Quality assurance measures within DIN 6856: the adaptation of film viewing boxes and their specifications in the radiology department of a university hospital. Deutsche Industrie-Norm].

PURPOSE: The aim of our study was to examine the quality and consistency of film viewing equipment and surroundings for radiological film viewing as stipulated by the recently released DIN 6856 standard specifications sheet. METHODS: 107 film viewers in 43 locations in the Department of General Radiology (Hospital of the Goethe University in Frankfurt, Germany) were examined with regard to viewer brightness (intrinsic luminous intensity) uniformity of viewbox brightness, colour of fluorescence tubes, dimensions, adjustable filters, positioning of the viewers and ambient light level. RESULTS: Requirements regarding brightness were met in 70%, whereas conditions regarding uniformity of brightness were fulfilled in only 27% and the required filters in only 20% of all cases. CONCLUSIONS: 89% of the examined film viewboxes did not comply with the strict specifications laid down in DIN 6856. The requirements regarding the ambient light level (recommended range 50-100 lx) were met by only 75% of the examined desks.

Germany↗
PubMed1996

Intracranial pressure and hemodynamic effects of remifentanil versus alfentanil in patients undergoing supratentorial craniotomy.

Remifentanil hydrochloride is an ultra-short-acting esterase metabolized mu-opioid receptor agonist. The purpose of this study was to provide preliminary information regarding the effects of this drug on intracranial pressure (ICP) and mean arterial pressure (MAP) in patients scheduled for craniotomy. Twenty-six patients undergoing excision of supratentorial space-occupying lesions were anesthetized with 0.3-0.8 vol% isoflurane in a 2:1 mixture of nitrous oxide:oxygen. Ventilation was adjusted to provide a Paco2 of < 30 mm Hg. After the first burr hole was drilled, patients (n = 5-6 per group) were administered an intravenous infusion of study drug (placebo, remifentanil 0.5 micrograms/kg or 1.0 micrograms/kg, or alfentanil 10 micrograms/kg or 20 micrograms/kg) over 1 min. Epidural ICP and MAP values were recorded at baseline, at completion of infusion, and every minute for the next 10 min. Blood study drug concentrations were measured immediately after completion of infusion. Neither opioid caused a significant increase in ICP. Both drugs were associated with a dose-dependent decrease in MAP. Remifentanil was 31 times more potent than alfentanil for effects on MAP. We conclude that remifentanil produces similar cerebral perfusion pressure effects as does alfentanil.

Adult↗
PubMed1996

Ty3 integrase mutants defective in reverse transcription or 3'-end processing of extrachromosomal Ty3 DNA.

Ty3, a retroviruslike element in Saccharomyces cerevisiae, encodes an integrase (IN) which is essential for position-specific transposition. The Ty3 integrase contains the highly conserved His-Xaa(3-7)-His-Xaa(23-32)-Cys-Xaa(2)-Cys and Asp, Asp-Xaa(35)-Glu [D,D(35)E] motifs found in retroviral integrases. Mutations were introduced into the coding region for the Ty3 integrase to determine the effects in vivo of changes in conserved residues of the putative catalytic triad D,D(35)E and the nonconserved carboxyl-terminal region. Ty3 viruslike particles were found to be associated with significant amounts of linear DNA of the approximate size expected for a full-length reverse transcription product and with plus-strand strong-stop DNA. The full-length, preintegrative DNA has at each 3' end 2 bp that are removed prior to or during integration. Such 3'-end processing has not been observed for other retroviruslike elements. A mutation at either D-225 or E-261 of the Ty3 integrase blocked transposition and prevented processing of the 3' ends of Ty3 DNA in vivo, suggesting that the D,D(35)E region is part of the catalytic domain of Ty3 IN. Carboxyl-terminal deletions of integrase caused a dramatic reduction in the amount of Ty3 DNA in vivo and a decrease in reverse transcriptase activity in vitro but did not affect the apparent size or amount of the 55-kDa reverse transcriptase in viruslike particles. The 115-kDa viruslike particle protein, previously shown to react with antibodies to Ty3 integrase, was shown to be a reverse transcriptase-IN fusion protein. These results are consistent with a role for the integrase domain either in proper folding of reverse transcriptase or as part of a heterodimeric reverse transcriptase molecule.

Amino Acid Sequence↗
PubMed1996

[Postoperative radiotherapy in the prevention of heterotopic ossification after endoprosthetic hip joint replacement].

BACKGROUND: Following total hip arthroplasty high-grade heterotopic ossification occurs with a range of 0.5 to 27%. Local postoperative hip irradiation using different dosage and fractionation schedules reduces the incidence in high-risk cases on an average of 8%. The present retrospective study compares results after conventionally fractionated and high-dose radiotherapy. PATIENTS AND METHOD: A total of 50 hips (46 patients) from 2 different risk groups had complete follow-up. In group I (40 hips [80.0%]) radiotherapy was indicated after surgical excision of pre-existing high-grade heterotopic ossification, in group II (10 hips [20.0%]) for several risk factors (contralateral heterotopic ossification [n = 7], hypertrophic osteoarthritis [n = 2], spondylosis hyperostotica [n = 1]). In 28/50 cases (56.0%) conventionally fractionated irradiation with total doses ranging from 12.0 to 20.0 Gy was given, in 22/50 hips (44.0%) a high-dose irradiation consisting of 10.0 Gy given in 2 fractions on each of the first 2 postoperative days was applied. After a minimal observation period of 6 months (median: 22 months, range: 6 to 56 months) roentgenograms were analysed using a modified Brooker score. RESULTS: At follow-up, 2 hips in group I had recurrence of high-grade heterotopic ossification with the stages IIIA and IVB. In 1 case radiotherapy was interrupted after 3 x 2.0 Gy due to sepsis (IIIA), in the other case ectopic bone recurred from bony islands which layed outside the radiation portal (IVB). In group II, 9 patients had stage 0 and 1 patient stage IA. Statistical analysis using the Wilcoxon test showed a highly significant reduction of the amount of pre-existing heterotopic ossification (p < 0.0001) for both fractionation schedules. The comparison of both fractionation groups with the Whitney-Mann-U-test (p = 0.92) showed no statistical significant difference. CONCLUSIONS: The data about the high therapeutic efficacy of postoperative radiotherapy for prevention of heterotopic ossification were confirmed. Both fractionation schedules led to a sufficient reduction of high-grade heterotopic ossification in the 2 treated risk groups.

Adult↗
PubMed1996

[Pneumoperitoneum and pneumoretroperitoneum without perforation].

Asymptomatic radiologically recognised pneumoperitoneum still remains a diagnostic and therapeutic dilemma, because free intraperitoneal air is not necessarily caused by alimentary tract perforation. We present two cases of nonsurgical pneumoperitoneum (caused by pneumomediastinum and pneumatosis intestinalis cystoides) and their typical radiologic findings. Other causes of pneumoperitoneum that do not necessitate laparotomy so as cited in the radiologic and surgical literature are discussed.

Adult↗
PubMed1996

[Universal organ involvement in Rendu-Osler-Weber disease: interdisciplinary diagnosis and interventional therapy].

A case of hereditary hemorrhagic teleangiectasia (HHT, Morbus Rendu-Osler-Weber) in a 63-years-old patient presenting with recurrent gastrointestinal and nasopharyngeal bleeding who required transfusion of 100-200 units of red blood cell concentrate a year is reported. Endoscopically, one source of bleeding could be located in the upper part of the jejunum. Multiple Osler spots were found in the antrum, the bulbal and descending part of the duodenum without signs of bleeding. Colonoscopy revealed no further lesions. Selective mesentericography visualized dilatation of the arterial arcardes in the duodenal region with early venous filling. During coeliacography, parenchymal deposits of contrast medium appeared in the liver. Numerous angiodysplastic arterial alterations from the lower ethmoidal arteria were shown to be another source of bleeding. They were embolized using microspheres and thereby terminating epistaxis. Termination of epistaxis was the crucial prerogative for the consecutive aortal valve replacement. At abdominal ultrasound, the liver harbored multiple anechoic lesions and a bigger cystic formation with portal inflow and early venous distribution. This teleangiectatic portovenous-malformation was confirmed on abdominal computertomography and on T1-enhanced images of MRT, too. This case examplifies the universal character of organ distribution in HHT and underlines the value of complementary diagnostic and therapeutic modalities.

Combined Modality Therapy↗
PubMed1995

Requirement of RNA polymerase III transcription factors for in vitro position-specific integration of a retroviruslike element.

The yeast retroviruslike element Ty3 inserts at the transcription initiation sites of genes transcribed by RNA polymerase III (Pol III). An in vitro integration assay was developed with the use of Ty3 viruslike particles and a modified SUP2 tyrosine transfer RNA (tRNA(Tyr)) gene target. Integration was position-specific and required Ty3 integrase, Pol III transcription factor (TF) IIIB-, TFIIIC-, and Pol III-containing fractions showed that TFIIIB and TFIIIC, together, were sufficient for position-specific Ty3 integration, but not for transcription. This report demonstrates that in vitro integration of a retroelement can be targeted by cellular proteins.

DNA Nucleotidyltransferases↗