Innovative biochemisurgical treatment for stabilisation of an end-stage chronic wound in a complex vascular compromized patient

INTRODUCTION

Treating advanced peripheral arterial occlusive disease (e.g. PAOD IV) poses a significant challenge, as conventional treatments quite often fall short at this stage. However, a range of interventions can be considered to postpone amputation. This study presents an example of advanced stage of Peripheral Artery Occlusive Disease (PAOD) stage IV, encompassing a history of a high thigh amputation on the left side, coupled with pronounced wound healing disorders.

PRESENTATION OF CASE

Our patient, 55 years old, smoker and ASA Class III is in a left sided above-the knee-amputation situation. He presented to our outpatient clinic with blistering in the stump area, caused by non-proportinate pressure from the prosthesis. With an emerging septic course and advanced peripheral arterial occlusive disease (PAOD) at Fontaine class IV, revascularization was unfeasible in the left iliac artery axis and groin arteries. Additionally, a stage PAOD IV presents itself with poorly healing wounds on the right side which our patient still uses to support his transfers in and out bed and his wheelchair. Multiple surgical stump revisions and femur shortenings and diverse wound treatments were performed all were unsatisfying for patient and practitioners. We introduced a novel biochemisurgical treatment in our teaching hospital.

DISCUSSION

Desiccating-agent-A is an innovative dehydrating agent with potent desiccating characteristics upon application to organic substances. Its formulation involves blending 83% methane sulfonic acid with proton acceptors and dimethyl sulfoxide, as outlined in patent application. The case description results in an illustrated follow up period of 16 months and is presented in line with the recommendations of the consensus-based surgical case reporting guideline development.

CONCLUSION

The goal of achieving a secondary healing trend is to establish stability within the wound area or achieve complete healing. This endeavor becomes particularly intricate when severe blood circulation compromise exists. Nonetheless, progress in wound treatment measures has made it feasible to achieve this aim by fostering the formation of dry and clean necrotic tissue. This dry and clean wound is now manageable in a patient's home situation, allowing for effective care and a better chance at preventing further severe complications.

Noncovalent Interactions in Halogenated Pyridinium Salts of the Weakly Coordinating Anion [Al(OTeF5 )4 ]. Chemistry 2023;29:e202202749. [PMID: 36268910 PMCID: PMC10107151 DOI: 10.1002/chem.202202749]

The synthesis and the first structural characterization of the halogenated pyridinium salts [C₅ F₅ NH]⁺ , [C₅ F₄ ClNH]⁺ , [(C₅ F₅ N)₂ H]⁺ , [(C₅ Cl₅ N)₂ H]⁺ of the weakly coordinating anion (WCA) [Al(OTeF₅ )₄ ]^- , showing noncovalent interactions in the solid state, are presented. The salts were characterized by the multinuclear NMR and IR spectroscopy as well as X-ray diffraction. Hirshfeld surface analysis and solid state structures reveal various intermolecular anion-π and σ-hole interactions between the corresponding halogenated pyridinium cations and the anion [Al(OTeF₅ )₄ ]^- .

Electron Beam-Treated Enzymatically Mineralized Gelatin Hydrogels for Bone Tissue Engineering

Biological hydrogels are highly promising materials for bone tissue engineering (BTE) due to their high biocompatibility and biomimetic characteristics. However, for advanced and customized BTE, precise tools for material stabilization and tuning material properties are desired while optimal mineralisation must be ensured. Therefore, reagent-free crosslinking techniques such as high energy electron beam treatment promise effective material modifications without formation of cytotoxic by-products. In the case of the hydrogel gelatin, electron beam crosslinking further induces thermal stability enabling biomedical application at physiological temperatures. In the case of enzymatic mineralisation, induced by Alkaline Phosphatase (ALP) and mediated by Calcium Glycerophosphate (CaGP), it is necessary to investigate if electron beam treatment before mineralisation has an influence on the enzymatic activity and thus affects the mineralisation process. The presented study investigates electron beam-treated gelatin hydrogels with previously incorporated ALP and successive mineralisation via incubation in a medium containing CaGP. It could be shown that electron beam treatment optimally maintains enzymatic activity of ALP which allows mineralisation. Furthermore, the precise tuning of material properties such as increasing compressive modulus is possible. This study characterizes the mineralised hydrogels in terms of mineral formation and demonstrates the formation of CaP in dependence of ALP concentration and electron dose. Furthermore, investigations of uniaxial compression stability indicate increased compression moduli for mineralised electron beam-treated gelatin hydrogels. In summary, electron beam-treated mineralized gelatin hydrogels reveal good cytocompatibility for MG-63 osteoblast like cells indicating a high potential for BTE applications.

Impact of high-energy electron irradiation on mechanical, structural and chemical properties of agarose hydrogels

Due to their excellent biocompatibility and biodegradability, natural hydrogels are highly demanded biomaterials for biomedical applications such as wound dressing, tissue engineering, drug delivery or three dimensional cell culture. Highly energetic electron irradiation up to 10 MeV is a powerful and fast tool to sterilize and tailor the material's properties. In this study, electron radiation treatment of agarose hydrogels was investigated to evaluate radiation effects on physical, structural and chemical properties. The viscoelastic behavior, surface hydrophilicity and swelling behavior in a range of typical sterilization doses of 0 kGy to 30 kGy was analyzed. The mechanical properties were determined by rheology measurements and decreased by more than 20% compared to the initial moduli. The number average molecular weight between crosslinks was estimated based on rubber elasticity theory to judge on the radiation degradation. In this dose range, the number average molecular weight between crosslinks increased by more than 6%. Chemical structure was investigated by FTIR spectroscopy to evaluate the radiation resistance of agarose hydrogels. With increasing electron dose, an increasing amount of carbonyl containing species was observed. In addition, irradiation was accompanied by formation of gas cavities in the hydrogels. The gas products were specified for CO₂, CO and H₂O. Based on the radiolytic products, a radiolysis mechanism was proposed. Electron beam treatment under high pressure conditions was found to reduce gas cavity formation in the hydrogels.

Improved Access to Organo-Soluble Di- and Tetrafluoridochlorate(I)/(III) Salts

A facile one-pot gram-scale synthesis of tetraalkylammonium tetrafluoridochlorate(III) [cat][ClF4 ] ([cat]=[NEt3 Me]+ , [NEt4 ]+ ) is described. An acetonitrile solution of the corresponding alkylammonium chloride salt is fluorinated with diluted fluorine at low temperatures. The reaction proceeds via the [ClF2 ]- anion which is structurally characterized for the first time. The potential application of [ClF4 ]- salts as fluorinating agents is evaluated by the reaction with diphenyl disulfide, Ph2 S2 , to pentafluorosulfanyl benzene, PhSF5 . The CN moieties in acetonitrile and [B(CN)4 ]- are transferred in CF3 groups. Exposure of carbon monoxide, CO, leads to the formation of carbonyl fluoride, COF2 , and elemental gold is dissolved under the formation of tetrafluoridoaurate [AuF4 ]- .

Contact Guidance by Microstructured Gelatin Hydrogels for Prospective Tissue Engineering Applications

Design of functionalized biomimetic scaffolds is one of the key approaches for regenerative medicine and other biomedical applications. Development of engineered tissue should optimize organization and function of cells and tissue in vitro as well as in vivo. Surface topography is one factor controlling cellular behavior and tissue development. By topographical patterning of biocompatible materials, highly functionalized scaffolds can be developed. Gelatin is hereby a promising candidate due to its biocompatibility and biodegradability. It is low in cost and easy to handle, enabling a variety of applications in science and medicine. However, for biomedical applications at physiological conditions, gelatin has to be additionally stabilized since its gel-sol-transition temperature lies beneath the human body temperature. This is realized by a reagent-free cross-linking technique utilizing electron beam treatment. By topographical patterning, gelatin can be functionalized toward scaffolds for cell cultivation and tissue development. Thereby, customized patterns are transferred onto gelatin hydrogels via molds. Thermal stabilization of gelatin is then achieved by electron-induced cross-linking. In this study, we investigate the influence of gelatin concentration and irradiation dose on pattern transfer, long-term stability of topographically patterned gelatin hydrogels, and their impact on the cellular behavior of human umbilical vein endothelial cells as well as normal human dermal fibroblasts. We will show that contact guidance occurs for both cell types due to a concrete stripe pattern. In addition, the presented studies show a high degree of cytocompatibility, indicating a high potential of topographically patterned gelatin hydrogels as tissue development scaffold for prospective biomedical applications.

Programing stimuli-responsiveness of gelatin with electron beams: basic effects and development of a hydration-controlled biocompatible demonstrator

Biomimetic materials with programmable stimuli responsiveness constitute a highly attractive material class for building bioactuators, sensors and active control elements in future biomedical applications. With this background, we demonstrate how energetic electron beams can be utilized to construct tailored stimuli responsive actuators for biomedical applications. Composed of collagen-derived gelatin, they reveal a mechanical response to hydration and changes in pH-value and ion concentration, while maintaining their excellent biocompatibility and biodegradability. While this is explicitly demonstrated by systematic characterizing an electron-beam synthesized gelatin-based actuator of cantilever geometry, the underlying materials processes are also discussed, based on the fundamental physical and chemical principles. When applied within classical electron beam lithography systems, these findings pave the way for a novel class of highly versatile integrated bioactuators from micro- to macroscales.

Matrix-isolation and comparative far-IR investigation of free linear [Cl3]−and a series of alkali trichlorides

Here we discuss the reaction products of laser ablated alkali chlorides and elemental chlorine.

Differential modulation of the lipid metabolism as a model for cellular resistance to fumonisin B1-induced cytotoxic effects in vitro

Differential sensitivity of primary hepatocytes and Chang cells to the cancer promoter fumonisin B1 (FB1)-induced cytotoxic effects were investigated in relation to changes in membrane lipid distribution. In contrast to primary hepatocytes, Chang cells were resistant to FB1-induced cytotoxic effects. This was associated with a high cholesterol (Chol) and sphingomyelin (SM) and low phosphatidylcholine (PC) content, resulting in a significant (P<0.05) decrease in phosphatidylethanolamine (PE)/PC ratio, increased Chol/total phosphoglyceride (TPG) ratios and low total polyunsaturated fatty acids (PUFA) content in PC and PE, suggesting a more rigid membrane structure. High levels of C18:1 and reduced polyunsaturated fatty acid (PUFA) levels are likely to provide selective resistance to FB1-induced oxidative stress. FB1-associated lipid changes included decreases in SM and Chol, increases in sphinganine (Sa) and PE with the increases in key saturated, monounsaturated, and PUFAs in PE as key role players in the differential responses to FB1-induced cell growth responses in cells.

Induction of an altered lipid phenotype by two cancer promoting treatments in rat liver

Changes in lipid metabolism have been associated with tumor promotion in rat liver. Similarities and differences of lipid parameters were investigated using the mycotoxin fumonisin B1 (FB1) and the 2-acetylaminofluorene/partial hepatectomy (AAF/PH) treatments as cancer promoters in rat liver. A typical lipid phenotype was observed, including increased membranal phosphatidylethanolamine (PE) and cholesterol content, increased levels of C16:0 and monounsaturated fatty acids in PE and phosphatidylcholine (PC), as well as a decrease in C18:0 and long-chained polyunsaturated fatty acids in the PC fraction. The observed lipid changes, which likely resulted in changes in membrane structure and fluidity, may represent a growth stimulus exerted by the cancer promoters that could provide initiated cells with a selective growth advantage. This study provided insight into complex lipid profiles induced by two different cancer promoting treatments and their potential role in the development of hepatocyte nodules, which can be used to identify targets for the development of chemopreventive strategies against cancer promotion in the liver.

Investigation of alkali metal polyfluorides by matrix-isolation spectroscopy

From CsF crystals to molecular polyfluorides.

[Pulmonary capillary blood volume and membrane components of pulmonary diffusion capacity in patients with chronic obstructive bronchitis (COPD)]

Reduced pulmonary diffusion capacity is a hallmark of COPD, although the relative contribution of the subcomponents of pulmonary diffusion--membranous component (Dm) and capillary volume (Vc)--is unknown. These components can be measured with the method of NO single-breath diffusion (DLNO). In a prospective study, pulmonary function tests including spirometry, body plethysmography and single-breath measurements of diffusion capacity with CO and NO were performed in 183 patients with COPD of varying severity. There was a severity-dependent decrease in DLCO. Furthermore, Dm as well as Vc was positively correlated with the severity of COPD measured by FEV1. In all stages of COPD, reduction of Vc was more pronounced than constriction of Dm. In patients with most severe COPD, the preponderance of the reduction of Vc was significantly more marked than in milder stages.We conclude that Dm as well as Vc contributes to the reduction of DLCO in COPD, with a predominance of Vc at all stages of COPD. This confirms the idea that the loss of pulmonary capillaries in COPD is functionally relevant.

Enhanced reactivity and related optical changes of Ag nanoparticles on amorphous Al₂O₃ supports

Pairs of samples containing Ag nanoparticles (NPs) of different dimensions have been produced under the same conditions but on different substrates, namely standard glass slides and a thin layer of amorphous aluminum oxide (a-Al₂O₃) on-glass. Upon storage in ambient conditions (air and room temperature) the color of samples changed and a blue-shift and damping of the surface plasmon resonance was observed. The changes are weaker for the samples on-glass and tend to saturate after 12 months. In contrast, the changes for the samples on a-Al₂O₃ appear to be still progressing after 25 months. While x-ray photoelectron spectroscopy shows a slight sulfurization and negligible oxidation of the Ag for the on-glass samples upon 25 months aging, it shows that Ag is strongly oxidized for the on a-Al₂O₃ samples and sulfurization is negligible. Both optical and chemical results are consistent with the production of a shell at the expense of a reduction of the metal core dimensions, the latter being responsible for the blue-shift and related to the small (<10 nm initial diameter) of the NPs. The enhanced reactivity of the Ag NPs on the a-Al₂O₃ supports goes along with specific morphological changes of the Ag NPs and the observation of nitrogen.

PCR offers no advantage over culture for microbiologic diagnosis in cellulitis

PURPOSE

Most cases of cellulitis are traditionally attributed to β-hemolytic Streptococcus and Staphylococcus species, although in most cases, no organism is identified. Development of PCR using the conserved bacterial 16 S rRNA DNA permits identification of bacteria independent of conventional culture approaches and prior use of antibiotics.

METHODS

We used PCR-based techniques to identify cellulitis etiology using aspirate samples from affected skin. Saline was infiltrated and aspirated at the site of greatest erythema or at the cellulitic border. Samples were tested for 16 S rRNA DNA, and organism-specific probes used to identify bacteria commonly seen in skin infections.

RESULTS

Aspirates from 32 patients were studied, and 16 S rRNA DNA was detected in nine of these patient samples (28.1%). Bacterial species were identified by PCR methods in six of these nine samples (66.6%), with S. aureus and methicillin-resistant S. aureus (MRSA) identified in four and two, respectively, of these samples. Of the patients with positive aspirate bacterial cultures (3/9, 33.3%), S. aureus and coagulase-negative Staphylococcus (CoNS) were present on cultures of two of the three (both 66.6%) positive samples. Only in one of the three positive bacterial cultures did the PCR method detect the same organism as was detected by culture. Among patients with positive provider-collected clinical cultures, MRSA was the predominant organism (11/18, 61.1%) and when present, it was found as the sole organism. Where S. aureus or Streptococcus species were detected by molecular methods, clinical cultures yielded a positive result as well.

CONCLUSIONS

PCR-based techniques do not appear to be more sensitive than aspirate cultures for the detection of pathogens in cellulitis.

Überprüfung des revidierten Trainings zur Förderung der Lesekompetenz und der Lesemotivation (LekoLemo) für die Sekundarstufe I

Zusammenfassung. Angeregt durch die Befunde der PISA-Studie und auf der Basis bisheriger Förderprogramme wurde das Lesetraining LekoLemo (Programm zur Förderung der LEseKOmpetenz und LEseMOtivation) für Schüler der 7. Jahrgangsstufe entwickelt. Das Training unterscheidet sich von bereits existierenden Lesetrainings vor allem durch zwei Aspekte: (1) Es umfasst Aufgaben zu den in der PISA-Studie verwendeten Dimensionen des Lesens Informationen ermitteln, textbezogenes Interpretieren sowie Reflektieren und Bewerten und (2) beinhaltet eine explizite Förderung der Lesemotivation. Die vorliegende Studie überprüfte das revidierte LekoLemo-Training anhand einer Stichprobe von 235 Siebtklässlern. Die Ergebnisse belegen die Wirksamkeit des Trainings und zeigen signifikante Effekte geringer bis mittlerer Größe auf die Lesekompetenz im Follow-up-Test. Demgegenüber erwiesen sich die Effekte auf die intrinsische Lesemotivation und das Selbstkonzept nicht nur als niedrig, sondern auch als nicht nachhaltig.

[Counselling centres for patients with cancer--analysis of service provision in Saxony]

OBJECTIVES

The aim of this study was to understand the quantity and quality of psychosocial services offered at counselling centres for outpatients with cancer in Saxony, a federal state of Germany.

METHODS

Structured interviews with employees on site at the counselling centres in Saxony (N=30) and an analysis of their yearly reports were undertaken.

RESULTS

The majority of the counselling centres (N=25) was situated at local health departments. All institutions document their activities regularly and offer continuous training for their employees. Services include primarily information on and admission to social services whereas psychological and psychotherapeutic services are rare. Considering the guideline criteria for staffing with a ratio of one counsellor per 75,000 inhabitants, a total of 23 counsellors were lacking in the federal state of Saxony at the time of investigation.

CONCLUSIONS

The method of situating counselling centres at local health departments ensures good access for almost all cancer patients and relatives seeking counselling. However, due to restricted financial resources the services offered are not sufficient according to the guidelines and solutions for this situation are needed.

Neonatal Trichomonas vaginalis infection: a case report and review of literature

Neonatal infection with Trichomonas vaginalis is an unusual occurrence. We present a case of T. vaginalis found on routine urinalysis in a five-day-old neonate born at 29 weeks gestational age. The patient was treated with metronidazole and had complete resolution of the infection. This report discusses the significance of diagnosis and treatment of T. vaginalis in the neonate.

Antimicrobial use in Europe and antimicrobial resistance in Streptococcus pneumoniae

The study presented here determined the relationship between antimicrobial resistance in Streptococcus pneumoniae and the use of antimicrobial agents in 15 different European countries. Pneumococcal isolates (n = 1974) recovered from patients with community-acquired respiratory tract infections during the winter of 2004-2005 in 15 European countries were characterized. The overall percentages of isolates demonstrating intermediate or complete resistance to penicillin, erythromycin, tetracycline, trimethoprim-sulfamethoxazole (TMP-SMX) and ciprofloxacin were 24, 24.6, 19.8, 26.7 and 2%, respectively, as determined using the broth microdilution MIC method recommended by the Clinical and Laboratory Standards Institute. The overall and mean antimicrobial consumption levels (ACL)--i.e., the defined daily doses per 1,000 inhabitants per day--were obtained from the European Surveillance of Antimicrobial Consumption project for each of the 15 countries for the years 1998-2004. Using linear regression analysis, the mean annual ACL for beta-lactams, macrolides, tetracyclines, TMP-SMX and fluoroquinolones in each country was compared to the country-specific resistance rates determined in 2004-2005. The rate of overall antimicrobial use in all 15 European countries was significantly associated with antimicrobial resistance in S. pneumoniae. There was variation among the different antimicrobial classes as drivers of resistance, with beta-lactams having the strongest association.

Kinder-Umwelt-Survey (KUS) im Rahmen des Kinder- und Jugendgesundheitssurveys (KiGGS)

The German Environmental Survey for Children (GerES IV) is the environment-related module of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) of the Robert Koch Institute and the fourth GerES of the Federal Environment Agency. The main objective of GerESs is to analyse and document the extent, distribution and determinants of exposure to environmental pollutants of the German general population. GerES IV was performed from 2003 to 2006. A total of 1.790 children aged 3-14 years from 150 sampling locations participated in GerES IV. Samples of blood, urine, tap water, house dust and indoor air were analysed. Hearing tests, measurements of traffic noise and interviews to get exposure-related information were conducted. First results indicate a clear decrease of the exposure to arsenic, lead and mercury. Cotinine concentrations in urine can be used to classify the exposure of children to environmental tobacco smoke. The examination of the tap water used in the subjects' households indicates that in some households the guideline values of the German Drinking Water Ordinance were not always met. This is the case for nickel, copper and lead which are used as pipe material for domestic plumbing.

[In-house questioning on patient satisfaction in a maximum resource clinic--report from practice]

Since 1999, the statutory obligation of all German hospitals to establish an internal quality management system has resulted in an increase of patient surveys on inpatient care. Information on the subjective satisfaction of the patients is of particular interest because improvements may be realised. In the present paper, the objectives, the methodology and the choice of a tested survey instrument, the interpretation of the results and the practical problems in implementing a survey on patient satisfaction at the Leipzig University Hospital (a public institution comprising 1,464 beds in 2001) will be reported. This is intended to facilitate comparable projects in the future and to enable hospitals with fewer resources to organize and use such surveys. Altogether, 1,718 questionnaires (Hamburg questionnaires on patient stay in hospital, HFK) from 43 wards could be evaluated. The high satisfaction determined (mean values of the scores for 10 test parameters are between 1.72 and 2.02 on a 5-point scale) corresponds to the general tendency of patients to make socially desirable responses. Covert dissatisfaction was therefore analysed comparing the relative frequencies of complete and limited satisfaction at item level. Sociodemographic patient characteristics such as age and stay in hospital were of no substantial relevance. One important aim of the Leipzig survey project was to give detailed feedback within brief time periods. The project focussed on a differentiated and early monitoring of responses. If requested, an oral presentation of the results was made to each structural unit. This presentation included the spontaneous responses of the patient, which enhanced the acceptance of the investigation by the medical staff.

IFN-gamma synergizes with TNF-alpha but not with viable H. pylori in up-regulating CXC chemokine secretion in gastric epithelial cells

Helicobacter pylori colonizes the gastric epithelial surface and induces epithelial cells to increase production of the neutrophil attractant IL-8. Little is known about the role of the gastric epithelium in regulating mucosal T cell trafficking. We therefore characterized constitutive and regulated epithelial expression of the CXC chemokines IP-10, I-TAC and Mig, which specifically attract CXCR3 expressing CD4(+) T cells. Human gastric epithelial cell lines (AGS, Kato III, NCI) were used to characterize the constitutive and regulated expression of three CXC chemokines in response to IFN-gamma, TNF-alpha and different H. pylori preparations. Chemokine mRNA and protein production were measured by RT-PCR and ELISA. Gastric epithelial cells constitutively expressed mRNA for IP-10, Mig and I-TAC. IFN-gamma in combination with TNF-alpha strongly induced secretion of those chemokines. Soluble or membranous fractions of H. pylori significantly inhibited IFN-gamma/TNF-alpha induced epithelial cell IP-10 and Mig production. Gastric epithelial cells may contribute to mucosal T cell trafficking. The capacity of H. pylori products to inhibit IP-10 and Mig secretion may explain, at least in part, the failure to induce protective immunity against this bacterium and the ability of H. pylori to affect the presentation of the local inflammation.

CD4+ Th1-cells predominate in low-grade B-cell lymphoma of gastric mucosa-associated lymphoid tissue (MALT type)

BACKGROUND

Little is known about the function of T cells in the inflammatory infiltrate in Helicobacter pylori-associated gastritis and B-cell lymphoma of mucosa-associated lymphoid tissue (MALT type). Previous studies have proposed a dominant Th1-type response in low-grade MALT lymphoma consistent with the Th1 response observed in H. pylori-associated gastritis.

METHODS

We performed a novel flow cytometric approach in which CD3 panning for enrichment and activation of small numbers of T cells and intracellular cytokine analysis were combined to selectively characterize the cytokine profile of T cells (IFN-gamma for Th1) derived from the gastric mucosa of 23 patients with low-grade MALT lymphoma stage IEI1 (lymphoma infiltration of mucosa/submucosa sparing the muscularis). Endosonography was performed in each case to control the depth of lymphoma infiltration. For comparison, 19 patients with H. pylori-positive gastritis were also analysed.

RESULTS

There was a CD4/CD8 ratio of 4 in patients with MALT lymphoma and of 2 in chronic gastritis. The proportion of IFN-gamma producing cells within the CD4-positive T-cell population in MALT lymphoma was 22%; in chronic gastritis it was 13% while no such difference could be encountered in CD8-positive T cells.

CONCLUSIONS

The data point towards a dominant intratumoral IFN-gamma dominated T-cell response associated with early low-grade MALT lymphoma. A polarized IFN-gamma dominated Th1-type response may either contribute to the inability of the immune system to eradicate H. pylori infection, thereby promoting the activation status of the lymphocytic infiltrate in low-grade MALT lymphoma, or may mirror a concomitant tumor-specific T-cell response accompanying early stages of tumor progression.

[Attitude of medical students toward the handicapped]

In their daily professional work physicians are increasingly faced with persons who live with chronic diseases or handicaps. Beyond profound medical knowledge, an understanding of psychosocial factors and a positive attitude are essential for providing optimal treatment. In order to teach the medical students of Leipzig University how to balance these factors they are required to visit self-help groups and institutions for disabled persons as part of the course "Social Medicine". 250 medical students of the 9th semester filled out a questionnaire designed to assess their attitudes toward handicapped persons as well as their motivation for choosing the medical profession. The questionnaire was given twice, once before their visitations and once following. 28 students of special supportive education served as a control group. While the attitudes of the medical students were very similar to those of the standard population, the attitudes of the supportive education students were significantly more positive. A comparison of the results of the questionnaires before and after the visitations showed that the attitudes of the medical students remained essentially the same without any obvious changes due to their experiences during the visitations. This evidence suggests that there needs to be more emphasis in Social Medicine and medical education in general placed on the problems specific to handicapped people.

[Validation of the acute physiology and chronic health evaluation (APACHE) III scoring system and comparison with APACHE II in German intensive care units]

OBJECTIVES

The aim of the study was to systematically validate the APACHE III scoring system concerning severity of illness classification and prediction of hospital mortality. Such data have not yet been determined in a large population of critically ill patients in germany.

METHODS

531 patients (ICU stay > 4 hours) were prospectively and consecutively investigated. The day-1-scores and risk-of-death predictions of APACHE III and APACHE II were determined. A comparison was performed between both scoring systems, and the correlation with the observed hospital mortality was examined.

RESULTS

For both main validation criteria, as were discrimination (areas under the ROC-curves: APACHE III 0.873; APACHE II 0.859) and calibration (goodness-of-fit testings; p > 0.05), both scoring systems provided satisfying results concerning hospital mortality, no system showing a significantly superior performance. Compared to the observed hospital mortality (13.4%), the prediction of APACHE III (13.2%) was extremely accurate, whereas the prediction of APACHE II was higher (16.8%). The standard (mortality index not significantly < or > 1.0) provided by APACHE III was fulfilled, while the standard given by APACHE II was surpassed. The mean scores and the mean risk-of-death predictions for non-survivors were significantly higher compared to survivors (P < 0.001). The individual score values of both systems were found to have a strong correlation (r = 0.922).

CONCLUSIONS

APACHE III (like APACHE II) provides a sufficient severity of disease classification and accurately predicts overall hospital mortality in a representatively large german population of a medical ICU. Therefore APACHE III can be regarded as validated for the use in comparable german ICUs. For use as a standard the more recently introduced APACHE III seems to be superior to the established but older APACHE II. However, each user will--depending on the particular questions to be addressed--carefully have to evaluate, if the improvement of prognostic accuracy really justifies the increased amount of workload necessary for calculating APACHE III score and risk prediction.

[Social medicine in the ecology curriculum--Leipzig experiences with a social medicine practicum]

Apart from only offering lectures, Leipzig university introduced, within the scope of the "Ecological course", a newly outlined practical training in the field of social medicine. The topics of this practical training were: living with handicaps: chronic illness; psychosocial problems. The training consisted of two seminars and one attendance at disabled persons' unions and self-help groups. In addition to that, extern experts held lectures on the feasibility of rehabilitation. Each team, consisting of 3-5 students, was expected to write a report on their attendance in order to prove their efforts. Later on, these reports suppled the basis for discussion in the second seminar. The high quality of these reports clearly shows the students' interest in this kind of training. Some especially interested students took an active part in a final scientific colloquium, delivering their own lecture reports. Summing up, this teaching concept proved truly successful and should be continued.

[Results of vascular surgery reconstructions after PTA]

From 1986 through 1994 263 patients underwent vascular treatment due to 266 PTA complications. Complications at the site of the puncture were found in 35 patients (13.2%), at the site of dilatation in 210 (78.9%), and due to macro-embolism in 21 (7.9%). The most frequent pathology was thrombosis in 135 patients (50.7%). 62% of all operations were performed immediately or few days after PTA. The primary (secondary) patency rate after one month in AK femoro-popliteal reconstructions was 84% (88%), in BK reconstruction 69% (74%), after aorto-iliac reconstruction 90% (96.8%), in renal artery reconstructions 96% (96%), and in surgical interventions in the innominate artery and the subclavian artery 100%. In our opinion the unfavourable early results, especially after BK femoro-popliteal reconstructions, are due to a deterioration of the run-off caused by peripheral microembolisation. Of the aorto-iliac and limb artery reconstructions 7.1% required major amputation. The second most frequent complications were wound infections in 6.5%.

Experience on the reversibility of the vibration-induced white finger disease

In connection with medical appraisements of the occupational disease No. 2104 "Vibration-induced vasospastic disease" 240 patients could be examined a first time, 94 of them a second time, 42 patients a third time and 11 patients a forth time. The interval between examinations was 2, 4 or 6 years respectively. The standard procedure besides clinical whole body examination included anamnestic questionnaire, cold-provocation test with infrared thermography and vibrotactile perception test. The evaluation of the diagnoses in principle followed the Stockholm vascular V and sensorineural SN stages and was used to establish the grade of disability for compensation. The re-examinations after 2-6 years gave information on the development of the health status after cessation of vibration exposure. In only about 54% of all cases there was any improvement, in 39% the health status was unchanged, in 7% aggravated. It is obvious that the reversibility of the VWF if any needs many years abstaining from vibration exposure.

Consideration of grip and push forces for the assessment of vibration exposure

There is much influence of the coupling forces between hand and grip of the vibrating tool on the measuring results as well as on the vibration effects on the hand-arm system. In a research project the effects of grip and push forces on acute responses of the hand-arm system under vibration conditions have been studied. Using these results of the biodynamic response, vibration perception threshold and subjective vibration sensation a bonus/malus system for a correction of the measured frequency-weighted r.m.s. acceleration was drafted, to assess the hand-arm vibration at the workplace: Since there is no difference between the acute effects of grip force and push force, so the forces have to be added and defined as coupling force Fcf. On the basis of this coupling force Fcf a correcting factor cF may be calculated. The factor amounts to 0.6 at Fcf = 20 N, 1.0 at Fcf = 120 N and 1.1 at Fcf = 200 N. To correct the measured weighted r.m.s. acceleration ahwz (Fcf) depending on coupling forces the r.m.s. acceleration has to be multiplied with the correcting factor cF. The drafted procedure enables to assess vibration exposure depending on coupling forces in a standardized way.

Partial purification of hog kidney sodium-D-glucose cotransport system by affinity chromatography on a phlorizin polymer

A brush border membrane fraction isolated from hog kidney cortex was solubilized with 0.5% Triton X-100 and subjected to affinity chromatography on a phlorizin polymer. As demonstrated by transport studies with reconstituted proteoliposomes, the polymer adsorbs the sodium-dependent D-glucose transport system. The latter can be eluted from the polymer by 0.5 M D-glucose. The purified fraction contains 0.4% of the membrane protein extract and exhibits a 20--30-fold higher transport activity than the crude membrane extract. Other brush border membrane proteins such as alkaline phosphatase and aminopeptidase M are markedly reduced in the purified fraction. Thus, affinity chromatography on a phlorizin polymer is a suitable tool for the isolation of the sodium-glucose transport system present in brush border membranes.

The use of octyl beta-D-glucoside as detergent for hog kidney brush border membrane

Octyl beta-D-glucoside was synthetized from alpha-acetobromoglucose with an improved method yielding a very pure product with a sharp melting point (108-109 degrees C) and free of intermediate products as judged by IR and NMR spectra. The yield of the synthesis is 66% when referred to alpha-acetobromoglucose. The potency of this compound as a detergent on hog kidney brush border membranes was compared to the action of Triton X-100. Octyl glucoside preferentially extracts aminopeptidase M and gamma-glutamyltranspeptidase in a concentration-dependent manner. The more deeply imbedded membrane enzyme, alkaline phosphatase, was relatively resistent to the action of octyl glucoside. In contrast, Triton X-100 extracted all membrane proteins to about the same extent. Additionally it was found that octyl glucoside can be removed from membrane extracts by Biobead SM 2. The capacity of the beads is about 170 mg detergent/g of dry Biobead SM 2. Thus octyl glucoside seems to be a useful tool for solubilization and purification of brush border membranes proteins.