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Biomedical subjects

H Hoffmann

Publications and source records attributed to H Hoffmann.

At least 91 records · Page 5Linked to original sources
PubMed1996

Bronchoplastic resection for non-small-cell lung cancer.

During the past 12 years, among 1478 operations for non-small-cell lung cancer (NSCLC), 102 (6.9%) bronchosplastic resections were performed. There were 74 lobectomies, 19 bilobectomies, and 9 pneumonectomies done by means of 72 sleeve-, 28 wedge resections, and 2 resections of the tracheal bifurcation. Atelectasis was observed in 6%, whereas anastomotic dehiscence occurred in 4%. Local complete resection was achieved in 81%. The 30-day mortality amounted to 4%. Our results demonstrate that bronchoplastic procedures represent a safe therapeutic option in the operative treatment of central NSCLC.

Carcinoma, Non-Small-Cell Lung↗
PubMed1996

Zebrafish mutations affecting retinotectal axon pathfinding.

We have isolated mutants in the zebrafish Danio rerio that have defects in axonal connectivity between the retina and tectum. 5-day-old fish larvae were screened by labeling retinal ganglion cells with DiI and DiO and observing their axonal projections to and on the tectum. 82 mutations, representing 13 complementation groups and 6 single allele loci, were found that have defects in retinal ganglion cell axon pathfinding to the tectum. These pathfinding genes fall into five classes, based on the location of pathfinding errors between eye and tectum. In Class I mutant larvae (belladonna, detour, you-too, iguana, umleitung, blowout) axons grow directly to the ipsilateral tectal lobe after leaving the eye. Class II mutant larvae (chameleon, bashful) have ipsilaterally projecting axons and, in addition, pathfinding mistakes are seen within the eye. In Class III mutant larvae (esrom, tilsit, tofu) fewer axons than normal cross the midline, but some axons do reach the contralateral tectal lobe. Class IV mutant larvae (boxer, dackel, pinscher) have defects in axon sorting after the midline and retinal axons occasionally make further pathfinding errors upon reaching the contralateral tectal lobe. Finally, Class V mutant larvae (bashful, grumpy, sleepy, cyclops, astray) have anterior-posterior axon trajectory defects at or after the midline. The analysis of these mutants supports several conclusions about the mechanisms of retinal axon pathfinding from eye to tectum. A series of sequential cues seems to guide retinal axons to the contralateral tectal lobe. Pre-existing axon tracts seem not to be necessary to guide axons across the midline. The midline itself seems to play a central role in guiding retinal axons. Axons in nearby regions of the brain seem to use different cues to cross the ventral midline. Mutant effects are not all-or-none, as misrouted axons may reach their target, and if they do, they project normally on the tectum. The retinotectal pathfinding mutants reveal important choice points encountered by neuronal growth cones as they navigate between eye and tectum.

Animals↗
PubMed1996

Mutations disrupting the ordering and topographic mapping of axons in the retinotectal projection of the zebrafish, Danio rerio.

Retinal ganglion cells connect to their target organ, the rectum, in a highly ordered fashion. We performed a large-scale screen for mutations affecting the retinotectal projection of the zebrafish, which resulted in the identification of 114 mutations. 44 of these mutations disturb either the order of RGC axons in the optic nerve and tract, the establishment of a topographic map on the tectum, or the formation of proper termination fields. Mutations in three genes, boxer, dackel and pinscher, disrupt the sorting of axons in the optic tract but do not affect mapping on the tectum. In these mutants, axons from the dorsal retina grow along both the ventral and the dorsal branch of the optic tract. Mutations in two genes, nevermind and who-cares, affect the dorsoventral patterning of the projection. In embryos homozygous for either of these mutations, axons from dorsal retinal ganglion cells terminate ventrally and dorsally in the tectum. In nevermind, the retinotopic order of axons along the optic nerve and tract is changed in a characteristic way as well, while it appears to be unaffected in who-cares. Two mutations in two complementation groups, gnarled and macho, affect the anteroposterior patterning of the projection. In these mutants, nasodorsal axons branch and terminate too soon in the anterior tectum. In 27 mutants belonging to six complementation groups, retinal axons do not form normal termination fields. Some implications for models concerning the formation of topographic projections are discussed.

Animals↗
PubMed1996

The osteocalcin gene promoter provides a molecular blueprint for regulatory mechanisms controlling bone tissue formation: role of transcription factors involved in development.

Characterization of regulatory sequences and their cognate binding factors in the bone-specific osteocalcin (OC) gene promoter has provided insight into mechanisms that control expression of the gene under diverse biological conditions. We present evidence for AP-1 motifs and two multipartite conserved regulatory sequences, the OC Box I (nt-99 to-76) and a site designated OC Box II (nt-136 to-130) in contributing to developmental and tissue-specific expression of osteocalcin. OC Box I is characterized by a homeodomain binding site and OC Box II is a recognition sequence for AML-1 (also called PEBP2 alpha), a runt homology-related DNA binding protein. Functional activity of the elements was established in osseous and non-osseous cell lines and is in part related to the binding of osteoblast-specific complexes which enhance OC transcription. The contribution of several elements and binding of multiple classes of transcription factors to independent elements in both these domains serve to illustrate the complexity of control required for tissue-specific OC expression.

Animals↗
PubMed1996

[Lymphadenectomy in bronchial carcinoma: facts and fiction].

Removal of mediastinal lymph nodes is essential for the surgical staging of lung cancer; it is therefore integral part of a curative surgical treatment. The accuracy of mediastinal staging - "biopsy" sampling or complete removal of mediastinal lymph nodes - is of significance since the N-status affects treatment and survival. Anatomical and technical considerations lead to the conclusion: Because of the anatomy of the lymph system a complete removal of all draining lymph vessels is not possible. However, accurate mediastinal staging is clearly recommended over "biopsy"-sampling. Future studies should focus on an improved histologic evaluation and should take other "new" factors affecting prognosis into consideration.

Biopsy↗
PubMed1995

A Double-Blind Multicenter Comparison of the Efficacy and Safety of Saruplase and Urokinase in the Treatment of Acute Myocardial Infarction: Report of the SUTAMI Study Group.

Background: Urokinase or two-chain urokinase-type plasminogen activator has been shown to be effective in the treatment of acute myocardial infarction. Its parent molecule, single-chain urokinase-type plasminogen activator (scu-PA), unlike urokinase, can selectively activate fibrin-bound plasminogen. The induced clot lysis is amplified by plasmin-triggered conversion of scu-PA to urokinase and by further plasmin generation. The aim of our study was to compare the efficacy and safety of recombinant unglycosylated scu-PA, or saruplase, and urokinase at doses considered optimal in patients with acute myocardial infarction within 6 hours of onset of pain. Methods and results: In a double-blind trial 543 patients were randomized to saruplase (20 mg bolus + 60 mg/hr) or urokinase (1.5 million unit bolus + 1.5 million units/hr). Primary endpoint: The patency rates at 24-72 hours were 75.4% (95% CI 70.3-80.5%) for saruplase and 74.2% (95% CI 69.0-79.4%; P = 0.77) for urokinase. Secondary endpoint: The incidence of bleeding events in both groups was 10.7%. There were three hemorrhagic strokes in the saruplase group (ns). Other efficacy and safety evaluations: Apart from the generation of more fibrinogen degradation products under saruplase, the changes in hemostatic parameters did not differ. Hospital mortality was 4.4% for saruplase and 8.1% for urokinase. This nonsignificant difference was maintained for 1 year. Conclusion: The efficacy and safety of saruplase and urokinase in the regimens used are very similar.

Journal Article↗
PubMed1995

Thrombolysis with recombinant unglycosylated single-chain urokinase-type plasminogen activator (saruplase) in acute myocardial infarction: influence of heparin on early patency rate (LIMITS study). Liquemin in Myocardial Infarction During Thrombolysis With Saruplase.

OBJECTIVES: The Liquemin in Myocardial Infarction During Thrombolysis With Saruplase (LIMITS) study was instituted to evaluate and characterize the effect of a prethrombolytic heparin bolus (5,000 IU) on the efficacy and safety of saruplase in patients with acute myocardial infarction. BACKGROUND: Heparin has been used after thrombolytic therapy for acute myocardial infarction to prevent reocclusion of the infarct-related artery. METHODS: The study was designed as a randomized, parallel-group, double-blind, multicenter trial. Patients were treated within 6 h of onset of symptoms with either a bolus of 5,000 IU of heparin (Liquemin) (n = 56, HSH group) or placebo (n = 62, PSH group) before thrombolytic treatment with saruplase given as a 20-mg bolus followed by an infusion of 60 mg over 60 min. Thirty minutes after completion of thrombolysis, an intravenous heparin infusion was administered for 5 days. Before coronary angiography was performed at 6 to 12 h after start of lysis, an additional bolus of 5,000 IU heparin was given to all patients. End points studied were patency of the infarct-related artery, changes in the hemostatic system and bleeding complications. RESULTS: In the HSH group (heparin-saruplase-heparin), 78.6% of patients had an open infarct-related vessel (Thrombolysis in Myocardial Infarction [TIMI] flow grade 2 or 3) compared with 56.5% in the PSH group (placebo-saruplase-heparin) (intention-to-treat analysis, p = 0.01). No significant difference was observed between the two groups with regard to changes in fibrinogen and fibrin/fibrinogen degradation products. A total of eight bleeding complications (14.3%) were observed in the HSH group and five (8.1%) in the PSH group; no cerebrovascular event occurred, and no allergic reaction was reported. A total of 12 patients died during the hospital stay, 3 in the HSH group (5.4%) and 9 in the PSH group (14.5%). CONCLUSIONS: In acute myocardial infarction, the administration of a heparin bolus before thrombolytic therapy with saruplase is associated with a significantly higher patency at angiography 6 to 12 h after the start of thrombolysis without any appreciable increase in risk of bleeding.

Adult↗
PubMed1995

Gels from surfactant solutions with densely packed multilamellar vesicles.

Results on surfactant gels containing densely packed multilamellar vesicles are reported. The gels form spontaneously when the bilayers of L alpha or L3 phases of alkyldimethylaminoxide and cosurfactant are charged up by the addition of ionic surfactant or HCl. The rheological behaviour on addition of excess salt was studied by dynamic rheological measurements for systems with surfactants of different chainlengths. Both the storage modulus, G', and the yield stress, sigma y, decay with rising salinity. This effect is caused by the reduction of both the electrical contribution of the bending constants of the bilayers and the compression modulus of the vesicles. The influence of the charge density on the rheological properties was determined. G' and sigma y increase with charge density and reach a plateau that depends on the chainlength of the surfactant. Measurements on samples prepared with waterglycerol mixtures show that the moduli and the yield stress value are independent of the solvent viscosity. Photographs of the surfactant gels that were taken with the interference contrast microscopy technique are presented. They reveal that some of the vesicles are much bigger than expected on the basis of TEM micrographs. The mean size of the vesicles can be estimated on basis of conductivity data. This method yields an average number of 5-6 shells per vesicle and corresponds with the value taken from the electron micrograph. The rheological data are explained with a model that was recently introduced by van der Linden. In connection with a model due to Lekkerkerker for the electric contribution of the bending constant of the bilayers and our own calculations of the osmotic pressure the van der Linden formula yields good results for describing the experimental data.

Chemical Phenomena↗
PubMed1995

Amelioration of endotoxin-induced acute lung injury in pigs by HWA 138 and A 80 2715: new analogs of pentoxifylline.

We have evaluated the potential therapeutic effects of the xanthine derivatives HWA 138 (1-(5 hydroxy-5-methylhexyl)-3-methylxanthine) and A 80,2715 (1-(5 hydroxy-5-methylhexyl)-3-methyl-7-propylxanthine) on acute lung injury in endotoxemic pigs when administered following the septic insult. Salmonella abortus equi endotoxin (LPS) was given as a continuous intravenous infusion of 2 micrograms/kg/h over a period of 8 h. 1 h after the start of the LPS infusion the animals received a bolus injection followed by continuous infusion of A 80,2715 (3 mg/kg + 1.5 mg/kg/h; n = 6), HWA 138 (3 mg/kg + 1.5 mg/kg/h; n = 6), or saline (LPS control; n = 6). Treatment with A 80,2715 or HWA 138 inhibited the LPS-induced increases in the pulmonary artery pressure (p < .05; ANOVA) and in lung wet/dry weight ratio (p < .05), and ameliorated the LPS-induced deterioration in lung mechanics (decreased lung dynamic compliance (p < .05); increased peak airway pressure (p < .05)). Xanthine treatment, however, failed to significantly improve arterial PO2 and did not affect peripheral leukopenia. The results of this study suggest a potential therapeutic role for HWA 138 and A 80,2715 in attenuating endotoxin-induced acute lung injury.

Animals↗
PubMed1995

Age as a factor in identifying young adult chronic patients who are difficult to treat.

Age younger than 35 years has been used as a factor in identifying young adult chronic mentally ill patients, a group considered difficult to treat due to their rebelliousness, lack of insight about their mental illness, and increased likelihood of showing symptoms of borderline or antisocial personality disorder. In a sample of psychiatric outpatients, the authors found that a subgroup of patients under age 35 fit this profile, while other patients under age 35 and nearly all patients over age 35 did not. The authors conclude that age is a legitimate factor in identifying a subgroup of challenging patients and that such patients may outgrow many troublesome characteristics as they age.

Adult↗
PubMed1995

[Morbidity and long-term survival after bronchoplastic resection of non-small-cell bronchial carcinoma].

During the past 12 years, among 1384 operations for NSCLC, 96 (6.9%) bronchoplastic resections were performed. There were 68 lobectomies, 19 bilobectomies and 9 pneumonectomies done by means of 66 sleeve resections, 28 wedge resections and 2 resections of the tracheal bifurcation. Atelectasis and anastomotic dehiscence were observed in 5 and 4%, respectively. A local complete resection was achieved in 81%. The 30-day mortality was 4%. The results show, that bronchoplastic procedures represent a safe therapeutic option in the operative treatment of centrally located NSCLC.

Aged↗
PubMed1995

[Theory of schizophrenia and community psychiatry--conclusions from current models for management].

Starting with Ciompis model of "affect logic" I want to show that affective, cognitive and behavioral patterns, once emerged in psychosis, subsequently tend to repetition and chronification on account of psychological, social but also neuronal plasticity. In the discussion about reasons of the chronification process, negative symptoms become more and more relevant. Beside the primary negative symptoms, patients develop coping strategies to avoid a new relapse. These secondary negative symptoms, however, should not only be understood as an adaptation effort of internal "disturbing factors", but also of external ones, caused by the surroundings. Therefore, the patient's behavior should not be seen detached from his context. To see negative symptoms also as coping strategy has major therapeutical implications for community psychiatry, because of the involved option that negative symptoms can be replaced by more curative and less disabling behaviour, i.e. they are accessible to therapeutical efforts. That means for community psychiatry, however, to develop itself out of its deficit oriented treatment paradigm and to increase its therapeutical ambitions.

Affective Symptoms↗
PubMed1994

Age and other factors relevant to the rehospitalization of schizophrenic outpatients.

In this study 50 of 51 schizophrenic long-term patients treated by a community-based outpatient service were followed-up for 2 years. Factors known to be relevant for rehospitalization were correlated with the rate of hospitalizations 1) in the past, 2) during the last year and 3) during the follow-up period. We were particularly interested in the influence of the patient's age on readmission. In agreement with previous research, the results showed that the best predictor of future admissions was the number of previous hospitalizations. Age also has a high predictive value and correlates not only significantly with the hospitalization rates but also with other factors relevant for readmission such as drug compliance, antisocial behavior and suicidal risk. This, however, only partly explains the frequency of rehospitalization, as partial correlation shows. Although items concerning compliance were highly correlated with previous hospitalizations, they had less predictive value, contrary to the findings in the literature.

Adult↗
PubMed1994

[Social control, social support and therapy. The tension field of (social-)psychiatric treatment].

As generally in psychiatry the treatment concepts in social psychiatry base to a great extend on disease- and deficit models. These models, however, have their limits and run the risk to promote exactly that, what social psychiatry is fighting against: chronification. The question shall be discussed, if the systemic approach could be helpful to reduce (social) psychiatry's contribution on the process of chronification. Since ever psychiatric institutions have the mandate of social control and exclusion of social disturbing people from society. On the other hand, social support has become a cornerstone of rehabilitation in psychiatry. There the therapist becomes the manager of the disability. The (case-)manager subsequently takes over the responsibility for the future course. So he also gets power over the system to be treated. He decides, how much of social support and control is necessary. But then he gives up the aim of profoundly changing something in the sense that the patient can give up his symptoms and take more self-responsibility for his acting. The consequence is that the patient and psychiatry keep up each other: a coevolution develops. This leads to rigidity and makes changes difficult. By taking over responsibility the therapist becomes part of the system to be treated. So he looses his neutrality and also the possibility of therapeutical influence and change. The whole system quickly moves into a vicious circle of helplessness. Finally it will be reflected how someone, working in an institution, still can do therapy in this field of tension of (social) psychiatry.

Activities of Daily Living↗