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Biomedical subjects

W Hoffmann

Publications and source records attributed to W Hoffmann.

At least 163 records · Page 9Linked to original sources
PubMed1992

Implantation of self-expanding esophageal metal stents for palliation of malignant dysphagia.

Eleven self-expanding metal stents were perorally implanted in ten patients with locally advanced malignant obstruction of the esophagus. After bougienage of the strictures, the stents were painlessly inserted and properly released by means of an 18 French gauge delivery catheter. In all cases, the endoprostheses expanded to a diameter of 14-20 mm and achieved immediate improvement of dysphagia. One perforation was seen after a single session of dilatation and subsequent stent insertion. No other early complication was observed. After a median follow-up of 74 days (Range, 33-252 days), one of eight patients is still alive and 7 died of non-procedural causes. The grade of dysphagia improved from a mean of 2.9 to a mean of 1.6 and 2.0, respectively, depending on the follow-up period (scale 0-4). Esophageal reobstruction occurred in four patients due to food impaction (two patients) or tumor ingrowth into the stent through the wire mesh (two patients). Recanalisation of the obstructed stent lumen was achieved by endoscopic irrigation (two patients), laser therapy only (one patient) or diathermia with subsequent insertion of a conventional plastic endoprosthesis into the metal stent (one patient). The initial results are promising. The delivery system, the wide-bore diameter, the macroporous configuration and the low mass of the self-expanding stents would seem to be associated with a less traumatic insertion procedure and a lower rate of stent migration as compared with conventional prostheses. Technical improvement may be required for prevention of tumor infiltration. Controlled trials are warranted to determine the future role of metallic stents for palliation of esophagocardial tumors.

Adult↗
PubMed1992

Endoscopic laser lithotripsy with an automatic stone recognition system for basket impaction in the common bile duct.

In a patient with a common bile duct stone 28 mm in diameter, the traction wires of two basket catheters fractured during endoscopic mechanical lithotripsy. Disintegration of the concrement and removal of the impacted baskets failed even after extracorporeal application of 8,000 shockwaves. Pulsed dye laser lithotripsy was carried out via a 250 microns fiber which was advanced to the stone through a 6 French ERCP guiding catheter. Lithotripsy could be safely performed under fluoroscopic control since the laser used provides an automatic cut-out system upon tissue contact. 3,600 of 11,800 applied pulses were emitted with the total power setting and complete disintegration of the calculus was achieved. The baskets and the fragments could be removed endoscopically in the same session. Laser lithotripsy with a stone recognition system would seem to improve the applicability and safety of intracorporeal lithotripsy even when performed without direct visual guidance.

Aged↗
PubMed1992

Prospective evaluation of the use of endoscopic retrograde cholangiography prior to laparoscopic cholecystectomy.

Preoperative cholangiography and subsequent removal of bile duct stones may increase the efficacy of laparoscopic cholecystectomy and reduce the rate of conversion to open cholecystectomy. Since there is little data on the incidence of choledocholithiasis in this group of patients, we undertook a prospective study on the routine performance of ERC in 288 patients selected for laparoscopic cholecystectomy. ERC succeeded in 264 of the 288 patients (91.7%) and showed a normal bile duct system in 227 (86.0%). Atypical bile duct anatomy was seen in eight patients. Open cholecystectomy was performed in seven of them but was judged to be absolutely necessary in only two cases (one patient each with Caroli syndrome and Mirizzi syndrome). ERC also revealed bile duct stones in 29 of 264 patients (11.0%) which had not been suspected on the basis of clinical, laboratory and ultrasonographic findings in nine cases (3.4%). EPT succeeded in all of the 29 patients with choledocholithiasis but open cholecystectomy was subsequently performed in four patients due to incomplete bile duct clearance (n = 3) or temporary bleeding after EPT (n = 1). The rate of ERC/EPT-related morbidity was 2.8%. It is concluded from a risk-benefit analysis in these patients that ERC should be restricted to patients with suspected bile duct stones. Following this strategy, small ductal concrements and bile duct abnormalities will be missed in 6.4% of cases but the clinical relevance of these findings is still unclear. In patients with combined gallbladder and common bile duct stones, preoperative EPT plus subsequent laparoscopic cholecystectomy appears to be an effective and time-saving therapeutic regimen which should be compared with open cholecystectomy plus common bile duct exploration in future studies.

Bile Duct Diseases↗
PubMed1992

[Sequential parenteral and oral therapy with ofloxacin in urogenital infections].

125 hospitalized patients (56 men and 69 women) suffering from urinary tract infection (UTI) and 15 women with endometritis or pelvic inflammatory disease were treated with ofloxacin 6 mg/kg/d i.v. divided into 2 doses. Two thirds of the patients were switched to oral ofloxacin using the same dose regimen after 4 days. The median duration of treatment was 10 days. 98 patients were evaluable for efficacy: 45 had complicated lower UTI, 32 had upper UTI (75% of them with complications), 13 had endometritis and 8 an uncomplicated lower UTI. The most frequent complications of UTI were: obstruction (n = 27), indwelling catheters (n = 23), urinary concrements (n = 12), residual urine (n = 8) and a neurogenic bladder (n = 6). 22 patients had diabetes mellitus. A total of 103 pathogens was isolated from the urine of 85 patients, the most frequent being E. coli, Proteus spp. and Enterococcus faecalis. 98% of patients with UTI and 85% of patients with endometritis were clinically cured. Adverse drug events were observed in 6 patients.

Adolescent↗
PubMed1992

[Role of cholangiography in laparoscopic cholecystectomy].

Cholangiography in laparoscopic cholecystectomy is indicated for the detection of bile duct stones and for visualization of the biliary anatomy in particular cases. For a selective approach patients with gallbladder stones can be split into groups with a low, an intermediate and a high probability of choledocholithiasis by use of ultrasonographic and laboratory parameters. In this respect, the choledochal diameter is the most accurate criterion for the prediction of duct stones. A narrow lumen, detectable in almost one-half of the patients, indicates a less than 4% incidence of duct stones. Cholangiography seems to be unnecessary in this low risk group. However, endoscopic retrograde cholangiography (ERC) or intraoperative cholangiography is indicated in patients with a 7-12 mm width of common bile duct and/or an elevated serum bilirubin level due to 10-50% risk of choledocholithiasis. There are several therapeutic options in case of detected duct calculi. To date, laparoscopic bile duct clearance can not be reliably performed. In about 15% of the patients an even larger choledochol diameter is associated with a high chance of bile duct stones. ERC and in case of detected stones endoscopic papillotomy (EPT) should be routinely performed in these patients to facilitate elective laparoscopic cholecystectomy.

Cholangiography↗
PubMed1991

xP1 and xP4. P-domain peptides expressed in Xenopus laevis stomach mucosa.

Two different precursors for secretory polypeptides from the stomach of Xenopus laevis have been characterized by cDNA cloning. Both mature polypeptides are potential candidates for gastrointestinal growth factors. One, xP1, is the X. laevis homologue of the pS2 gene product consisting only of a single P-domain, whereas the second, xP4, is a novel polypeptide formed by four P-domains arranged in tandem. Northern analysis detected both transcripts in the stomach but not in the skin or the brain. In situ hybridizations localized the expression of both precursors in surface mucous cells of the gastric mucosa. With an antibody generated against the deduced C-terminal end of xP4, the mature polypeptide was investigated by Western analysis revealing N-glycosylation of xP4.

Amino Acid Sequence↗
PubMed1991

Reevaluation of the Cottbus Reinfarction Study with 30 mg aspirin per day 4 years after the end of the study.

Four to 6 years after the end of the Cottbus Reinfarction Study with 30, 60 and 1000 mg/day aspirin, the survivors (72% of the patients) were reevaluated under standardized conditions at the district hospital. Nearly all patients (82%) of the former 30 mg group took further on 30 mg aspirin daily whereas of the former 1000 mg group only 20% continued to take doses higher than 500 mg aspirin. Forty-five percent changed to very low doses. Whereas the death rate was nearly the same in all three former dosage groups the total reinfarction rate was higher (22.5%) in the previous 1000 mg group in comparison to the 30 mg group (17.4%, p less than 0.05). The non-fatal reinfarction rate was by 50% lower in the former 30 mg group compared with the previous 1000 mg group. In the age group 50-59 a 8.6% non-fatal reinfarction rate is contrasted to 1.7% reinfarctions in patients of the former 30 mg group (p less than 0.01). The risk factors were not significantly different in the three groups.

Aspirin↗
PubMed1991

Segmental renal hypoplasia of vascular origin causing renal hypertension in a 3-year-old girl.

A rare case of renal hypertension in a 3-year-old girl caused by segmental renal hypoplasia of vascular origin is presented. Resection of the hypoplastic segment of the kidney permitted successful treatment of the high blood pressure with preservation of renal function. Elevated plasma renin activity in the renal vein of the affected side and biochemical investigations demonstrated that the resected segment of the renal cortex was the source of the renin leading to hypertension by activation of the renin-angiotensin-aldosterone system.

Child, Preschool↗
PubMed1990

An integumentary mucin (FIM-B.1) from Xenopus laevis homologous with von Willebrand factor.

We present a new protein from X. laevis skin termed "frog integumentary mucin B.1" (FIM-B.1) with a general structure similar to FIM-A.1 (formerly "spasmolysin"). The central region consisting of tandem repeats of 11 amino acid residues is probably a target for extensive O-glycosylation, whereas the C-terminal cysteine-rich domain shows pronounced homology with the C1-C2 domains and the C-terminal end of von Willebrand factor. Furthermore, we describe homology with antistasin, an anticoagulant peptide from a leech. We also discuss some implications concerning the evolutionary origin of von Willebrand factor. In situ hybridization studies revealed the expression of FIM-B.1 exclusively in mucous glands of the skin. This is comparable with FIM-A.1 but is in contrast to all other physiologically active peptides, which are synthesized in granular glands.

Amino Acid Sequence↗
PubMed1990

Epirubicin and ifosfamide in patients with refractory breast cancer and other metastatic solid tumours.

The combination of ifosfamide (IFO) and epirubicin (EPI) has been found to be an effective regimen in the treatment of metastatic tumours and shows remarkable activity in heavily pretreated breast cancer patients. A combination of EPI (35 mg/m2 on days 1 and 2) and IFO (1.8-2.5 g/m2 on days 1-5) was given to 58 patients with refractory breast cancer (n = 23), metastatic sarcomas (n = 15) and other solid tumours (n = 20). Due to extensive prior therapy, the IFO dose had to be adapted to the individual haematological situation. In all, 55 patients were evaluable; we observed 5 complete (CRs) and 16 partial responses (PRs). In addition, 18 patients experienced a minor response (MR) or no change (NC). The median duration of all responses was 6.7 months. Toxicity was generally mild and closely related to previous therapy.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

Expression of spasmolysin (FIM-A.1): an integumentary mucin from Xenopus laevis.

In the past, a unique type of precursor for a secretory protein was discovered. It contains a central repetitive domain rich in threonine residues and terminal cysteine-rich domains. Due to striking homologies of these terminal domains with pancreatic spasmolytic polypeptide, originally the name "prepro-spasmolysin" was proposed. Here we show that the mature protein has a MW of about 130 kDa, consisting of about 70% carbohydrate and 30% protein. Similar O-linked glycoproteins have been found in mucins from human intestine. For this and numerous other reasons we decided to rename this glycoprotein "frog integumentary mucin A.1" (FIM-A.1). Furthermore, analysis of the protein with specific antibodies against the predicted C-terminal end indicates that FIM-A.1 is probably not processed at pairs of basic residues. In situ hybridization as well as immunofluorescence studies revealed that FIM-A.1 is expressed and stored exclusively in mature mucous glands of Xenopus laevis skin. Only cone cells at the proximal part of these glands do not synthesize FIM-A.1. In contrast, all other physiologically active peptides from X. laevis skin investigated so far are synthesized in granular glands. A hypothetical function of FIMs for defense against microbial infections is discussed.

Amino Acid Sequence↗
PubMed1990

Biosynthesis and expression of ependymin homologous sequences in zebrafish brain.

Ependymins are unique, brain specific glycoproteins, which are major constituents of the cerebrospinal fluid. Originally, they were discovered in goldfish and are thought to be involved in synaptic plasticity. In the present study two transcripts were characterized in Brachydanio rerio originating from a single gene possibly by alternative splicing. These transcripts differ only in the length of their 3'-non-coding-regions and the encoded protein shares 90 and 88% homology with the two corresponding goldfish proteins, respectively. In situ hybridization revealed the expression of ependymins exclusively in the leptomeninx including its invaginations but not at all in the ependymal layer surrounding the ventricles. An initial developmental profile showed that ependymins first appear before hatching, i.e. between 48 and 72 h postfertilization.

Amino Acid Sequence↗
PubMed1990

[Alpha 2-interferon in kidney cancer. Experiences with 6 patients].

We report on 6 male patients with advanced renal cell carcinoma without prior chemotherapy. They were treated by recombinant alpha 2-interferon in a toxicity limited dosage. The maximal tolerated dose was 3 x 5 x 10(6) U/wk. to 3 x 20 x 10(6) U/wk., limited by flu-like symptoms in 5 cases, by thrombopenia in 1. We observed a response in 3 cases (2 partial remissions, 1 mixed response) lasting for 10, 11 and 13 months, respectively. This comparatively good result may be due to patient characteristics (little pretreatment, pulmonary metastasis, good performance status) as well as to a medium dosage. Occurrence of response after termination of interferon therapy in two cases are of particular interest.

Carcinoma, Renal Cell↗
PubMed1990

[Hutchinson-Horton ulcero-necrotizing cranial arteritis].

Arteritis cranialis ulcero-necroticans Hutchinson-Horton is the necrotizing variant of giant-cell temporal arteritis, which was first described by Hutchinson in 1890 and Horton in 1932. Although the histomorphological findings (occluding proliferation of the intima, destruction of the elastica interna, giant-cell infiltration) suggest reactive pathomechanisms, the aetiology of the disease remains rather uncertain. The hypothesis currently favoured is that auto-immunological processes originate from vascular alterations and subsequently lead to the recognition of antigenic determinants by the host immune system being followed by immunological response mechanisms clinically manifest as vasculitis. Arteritis cranialis is most frequently found in the temporal artery; however, the reasons for this preferential location are not clearly established, and giant-cell arteritis can also be found elsewhere. Ulceration of the skin can be encountered and may affect large areas of the scalp, depending on the vascular perfusion pattern involved. The case report described in this paper comprises anamnestic data, clinical and serological findings, and the histological picture typical for giant-cell arteritis. Stress is laid on the importance of early diagnosis to prevent irreversible complications with possibly fatal outcome.

Aged↗