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Biomedical subjects

S Schulz

Publications and source records attributed to S Schulz.

At least 19 recordsLinked to original sources

Implementation of evidence-based therapy in patients with systolic heart failure from 1998-2000.

BACKGROUND: In recent years, the incidence of systolic heart failure has increased. Besides a complete revascularization, guideline-based medication represents the most effective therapeutic approach. AIM: Analysis of adherence of guideline-recommended and actual medication during inpatient cardiac rehabilitation as well as under subsequent outpatient conditions. METHODS: From 01/1998 to 12/ 2000, 1346 consecutive patients (64 +/- 10 years, 73% male, LVEF 36.3 +/- 8%, 88% ischemic, 6.7% valvular cardiomyopathy, 5.3% other causes, 11.8% atrial fibrillation) were included in a singlecenter prospective register. Medication was recorded at discharge and after the follow-up period of 731 +/- 215 days. Trends in prescription rates were analyzed based on nonparametric correlations (Spearman's-Rho). Changes in medication from in- to outpatient settings were analyzed using exact McNemar test. RESULTS: At discharge 75.3% (67.9%/68.9%/ 86.6% in 1998/1999/2000, p <0.001) of the patients were treated as recommended. This rate dropped to 68.3% at followup (p <0.0001). Mortality within the follow-up period was low (12.6%). CONCLUSION: It could be shown that from 1998 to 2000 inpatient guideline conformity was implementable adequately. Outpatient conformity was significantly lower. Although a high proportion of correctly prescribed CHF medication could be demonstrated, a further effort to improve guideline adherence in the management of heart failure patients is desirable.

Aged↗

Induction of immunity and inflammation by interleukin-12 family members.

The interleukin (IL)-12 family is composed of three heterodimeric cytokines, IL-12 (p40p35), IL-23 (p40p19), and IL-27 (EBI3p28), and of monomeric and homodimeric p40. This review focuses on the three heterodimeric members of the IL-12 family. The p40 and p40-like (EBI3) subunits have homology to the IL-6R, the other subunits (p35, p19, and p28) are homologous to each other and to members of the IL-6 superfamily. On the basis of their structural similarity, it was expected that the members of the IL-12 family have overlapping pro-inflammatory and immunoregulatory functions. However, it was surprising that they also show very distinct activities. IL- 12 has a central role as a Th1-inducing and -maintaining cytokine, which is essential in cell-mediated immunity in nonviral infections and in tumor control. IL-23 recently emerged as an end-stage effector cytokine responsible for autoimmune chronic inflammation through induction of IL-17 and direct activation of macrophages. Very recently, IL-27 was found to exert not only a pro-inflammatory Thl-enhancing but also a significant anti-inflammatory function.

Animals↗

Linear and nonlinear methods for analyses of cardiovascular variability in bipolar disorders.

OBJECTIVES: Heart rate variability (HRV), blood pressure variability (BPV), and the assessment of baroreflex sensitivity are widely accepted methods for analyzing and characterizing cardiovascular regulation and for an enhanced risk evaluation in different diseases. As a result of the complexity of the investigated regulatory systems, univariate analyses do not often provide a convenient description of pathological changes in the cardiovascular regulation. Therefore, the application of a multivariate approach is preferable. METHODS: We present principal methods of time-domain, frequency-domain, and nonlinear analyses of HRV, BPV as well as methods for coupling and interaction analyses. RESULTS: Changes in autonomic nervous system (ANS) tone are known to accompany various mental disorders. Depressive patients frequently complain of symptoms of ANS dysfunction, such as dry mouth, diarrhea, and insomnia. These clinical observations propose the assumption of altered autonomic dysfunction in these patients. In contrast to these clinical assumptions, inconsistent results have been found in studies of HRV in depressive patients. This work therefore covers a brief review of the literature in respect to bipolar disorder and the rationale to study autonomic changes in such a psychiatric disease. CONCLUSIONS: Prospective studies of cardiovascular changes in mania and depression are needed to evaluate a psychopathological state in connection with cardiovascular changes and cardiac morbidity and mortality. These studies should consider BPV, coupling and interaction analyses, the application of nonlinear methods, and a multivariate approach in addition to the traditional analysis of HRV.

Autonomic Nervous System↗

The semantics of procedures and diseases in SNOMED CT.

OBJECTIVES: SNOMED CT is emerging as a reference terminology for the entire health care process. It claims to be founded on logic-based modelling principles. In this article, we analyze a special encoding scheme for diseases and procedures in SNOMED CT, the so-called relationship groups (RGs), which had been devised to avoid ambiguities in definitions. METHODS: We reformulate SNOMED CT's relationship groups in the format of description logics in order to check whether RGs serve the needs they were designed for. RESULTS: We show that a considerable proportion of relationship groups represent hidden mereological relations. We also report discrepancies encountered between the defined semantics of many SNOMED CT terms and their intuitive meaning, as well as inconsistencies detected between the definition of various complex composed terms and the definition of their top-level parents. CONCLUSIONS: We formulate recommendations for improving SNOMED CT by replacing most occurrences of relation groups by formally more adequate "part-of" relations.

Anatomy↗

Delta-opioid receptor-immunoreactive neurons in the rat cranial sensory ganglia.

Immunohistochemistry for delta-opioid receptor (DOR) was performed on the rat cranial sensory ganglia. The immunoreactivity was detected in 16%, 19% and 11% of neurons in the trigeminal, jugular and petrosal ganglia, respectively. The nodose ganglion was devoid of such neurons. DOR-immunoreactive (IR) neurons were mostly small to medium-sized (trigeminal, range = 62-851 microm(2), mean +/- SD = 359 +/- 175 microm(2); jugular, range = 120-854 microm(2), mean +/- SD = 409 +/- 196 microm(2); petrosal, range = 167-1146 microm(2), mean +/- SD = 423 +/- 233 microm(2)). Double immunofluorescence method revealed that all DOR-IR neurons were also immunoreactive for calcitonin gene-related peptide. The cutaneous and mucosal epithelia in the oro-facial region, tooth pulp, taste bud and carotid body were innervated by DOR-IR nerve fibers. In the brainstem, IR nerve terminals were located in the superficial medullary dorsal horn and dorsomedial part of the subnucleus oralis as well as the solitary tract nucleus. The present study suggests that DOR-IR neurons may be associated with nociceptive and/or chemoreceptive function in the cranial sensory ganglia.

Animals↗

Effect of Brn-3a deficiency on primary nociceptors in the trigeminal ganglion.

Immunohistochemistry for substance P, somatostatin and vanilloid receptor subtype 1 as well as receptors for somatostatin and opioids was performed on the trigeminal ganglion in wild-type and Brn-3a knockout mice at postnatal day 0. In wild-type mice, the trigeminal ganglion contained abundant substance P-, vanilloid receptor subtype 1-, sst2A receptor- and delta-opioid receptor-immunoreactive neurons, while the ganglion had only a few mu-opioid receptor-immunoreactive neurons. The Brn-3a deficiency had an effect on the cell size but not the number of substance P-immunoreactive neurons. In knockout mice, the proportion of small immunoreactive neurons markedly increased and that of medium- to large-sized immunoreactive ones correspondingly decreased (mean +/- S.D. = 54.7 +/- 29.1 microm2, range = 10.9-220.8 microm2) compared to wild-type mice (mean +/- S.D. = 116.6 +/- 58.6 microm2, range = 27.3-400.7 microm2). As for vanilloid receptor subtype 1-immunoreactive neurons, the number and cell size was barely affected by the deficiency. On the other hand, the loss of Brn-3a caused a decrease in the number of sst2A receptor- or delta-opioid receptor-immunoreactive neurons (more than 95% reduction) and an increase in the number of mu-opioid receptor-immunoreactive neurons (9.3-fold increase). Somatostatin-immunoreactive neurons were not detected in the trigeminal ganglion of wild-type or mutant mice at postnatal day 0. The present study suggests that Brn-3a deficiency may have effects on the survival of trigeminal nociceptors and their expression of some neurochemical substances.

Animals↗

[Neurological complications and loss of efficacy with intrathecal pain therapy].

In a new guideline issued by the German Association for the Study of Pain, intrathecal opioid therapy is described as proven to be effective with relatively few side effects. We reviewed this statement by analysis of the available literature and critical evaluation of the clinical course in a few of our own patients (n=3). In these cases (as well as in a further eight patients), explantation and a switch to oral opioids led to distinctly better alleviation of pain and abatement of the unwanted effects. The problems we discuss do not appear to be rare instances, but by all means complications that are frequently described. The long-term efficacy of intrathecal opioids has not been adequately verified; moreover, their potency is not high. The frequency of undesired events is comparable to that of oral opioid medication, but serious neurological complications are possible. To avoid dose escalations and to recognize neurological complications in time, diligent monitoring by the surgeon or an experienced pain center is essential.

Administration, Oral↗

Specific recognition, detoxification and metabolism of pyrrolizidine alkaloids by the polyphagous arctiid Estigmene acrea.

Evidence is presented that the polyphagous arctiid Estigmene acrea is well adapted to sequester and specifically handle pyrrolizidine alkaloids of almost all known structural types representative of the major plant families with pyrrolizidine alkaloid-containing species, i.e. Asteraceae with the tribes Senecioneae and Eupatorieae, Boraginaceae, Fabaceae, Apocynaceae and Orchidaceae. The adaptation of E. acrea to pyrrolizidine alkaloids includes a number of specialized characters: (i) highly sensitive recognition of alkaloid sources by pyrrolizidine alkaloid-specific taste receptors; (ii) detoxification of pyrrolizidine alkaloids by N-oxidation catalyzed by a specific flavin-dependent monooxygenase; (iii) transfer and maintenance of all types of pyrrolizidine N-oxides through all developmental stages; (iv) conversion of the various structures into the male courtship pheromone hydroxydanaidal most probably through retronecine and insect specific retronecine esters (creatonotines) as common intermediates; (v) specific integration into mating behavior and defense strategies. Toxic otonecine derivatives, e.g. the senecionine analogue senkirkine, which often accompany the common retronecine derivatives and which cannot be detoxified by N-oxidation do not affect the development of E. acrea larvae. Senkirkine is not sequestered at all. Non-toxic 1,2-saturated platynecine derivatives that frequently occur together with toxic retronecine esters are sequestered and metabolized to hydroxydanaidal, indicating the ability of E. acrea to aromatize saturated pyrrolizidines. Although pyrrolizidine alkaloids, even if they are offered continuously at a high level (2%) in the larval diet, are non-toxic, E. acrea larvae are not able to develop exclusively on a pyrrolizidine alkaloid-containing plant like Crotalaria. Therefore, E. acrea appears to be specifically adapted to exploit pyrrolizidine alkaloid-containing plants as "drug source" but not as a food source.

Animals↗

Cost analysis of a hospital-wide selective screening programme for methicillin-resistant Staphylococcus aureus (MRSA) carriers in the context of diagnosis related groups (DRG) payment.

The costs of a hospital-wide selective screening programme were analysed for a period of 19 months. During this time, 539 inpatients were screened, of whom 111 were MRSA-positive. Based on microbiological costs (staff and materials) and the costs of preventive contact isolation for 2 days until microbiological results were available (including material costs for medical consumable goods and the costs of additional nursing time), a total of 26,241.51 Euro was spent for the 539 patients screened. Based on cost units, the costs were 39.96 Euro for a patient found to be MRSA-negative and 82.33 Euro for a patient found to be MRSA-positive. Under the prospective diagnosis related groups (DRG) payment system in Germany, the costs of a prolonged hospital stay resulting from a hospital-acquired MRSA infection (HA-MRSA-I) are not reimbursed adequately by revenues, with a calculated average cost-revenue loss/patient with HA-MRSA-I of 5705.75 Euro. The screening programme was able to prevent 48% of predicted HA-MRSA-Is (35.2 patients with infection), thereby saving a predicted 200,782.73 Euro. After subtracting the screening costs, there was a net saving of 110,236.56 Euro annually. A sensitivity analysis of the break-even points for different screening frequencies and different MRSA incidence rates indicated that the screening programme became cost-effective at a low MRSA incidence rate, meaning that it can be recommended for most hospitals with an MRSA problem.

Carrier State↗

MorphoSaurus--design and evaluation of an interlingua-based, cross-language document retrieval engine for the medical domain.

OBJECTIVES: We propose an interlingua-based indexing approach to account for the particular challenges that arise in the design and implementation of cross-language document retrieval systems for the medical domain. METHODS: Documents, as well as queries, are mapped to a language-independent conceptual layer on which retrieval operations are performed. We contrast this approach with the direct translation of German queries to English ones which, subsequently, are matched against English documents. RESULTS: We evaluate both approaches, interlingua-based and direct translation, on a large medical document collection, the OHSUMED corpus. A substantial benefit for interlingua-based document retrieval using German queries on English texts is found, which amounts to 93% of the (monolingual) English baseline. CONCLUSIONS: Most state-of-the-art cross-language information retrieval systems translate user queries to the language(s) of the target documents. In contra-distinction to this approach, translating both documents and user queries into a language-independent, concept-like representation format is more beneficial to enhance cross-language retrieval performance.

Abstracting and Indexing↗

Interchanging lexical information for a multilingual dictionary.

OBJECTIVE: To facilitate the interchange of lexical information for multiple languages in the medical domain. To pave the way for the emergence of a generally available truly multilingual electronic dictionary in the medical domain. METHODS: An interchange format has to be neutral relative to the target languages. It has to be consistent with current needs of lexicon authors, present and future. An active interaction between six potential authors aimed to determine a common denominator striking the right balance between richness of content and ease of use for lexicon providers. RESULTS: A simple list of relevant attributes has been established and published. The format has the potential for collecting relevant parts of a future multilingual dictionary. An XML version is available. CONCLUSION: This effort makes feasible the exchange of lexical information between research groups. Interchange files are made available in a public repository. This procedure opens the door to a true multilingual dictionary, in the awareness that the exchange of lexical information is (only) a necessary first step, before structuring the corresponding entries in different languages.

Dictionaries, Medical as Topic↗

Breast cancer: patient information needs reflected in English and German web sites.

Individual belief and knowledge about cancer were shown to influence coping and compliance of patients. Supposing that the Internet information both has impact on patients and reflects patients' information needs, breast cancer web sites in English and German language were evaluated to assess the information quality and were compared with each other to identify intercultural differences. Search engines returned 10 616 hits related to breast cancer. Of these, 4590 relevant hits were analysed. In all, 1888 web pages belonged to 132 English-language web sites and 2702 to 65 German-language web sites. Results showed that palliative therapy (4.5 vs 16.7%; P=0.004), alternative medicine (18.2 vs 46.2%; P<0.001), and disease-related information (prognosis, cancer aftercare, self-help groups, and epidemiology) were significantly more often found on German-language web sites. Therapy-related information (including the side effects of therapy and new studies) was significantly more often given by English-language web sites: for example, details about surgery, chemotherapy, radiotherapy, hormone therapy, immune therapy, and stem cell transplantation. In conclusion, our results have implications for patient education by physicians and may help to improve patient support by tailoring information, considering the weak points in information provision by web sites and intercultural differences in patient needs.

Breast Neoplasms↗

Formation and analysis of mannosylerythritol lipids secreted by Pseudozyma aphidis.

Pseudozyma aphidis DSM 70725 was found to be a novel producer of mannosylerythritol lipids (MELs). The MELs were quantified by HPLC. Glucose as carbon source for precultivation supported growth well. By contrast, at concentrations >30 g l(-1) in preculture, subsequent MEL formation in the main culture with soybean oil as sole carbon source was reduced. The type of substrate supply considerably influenced MEL formation. High concentrations of soybean oil (80 ml l(-1)) at init favored the production process when compared to a stepwise (20 ml l(-1)) addition. Mannose or erythritol were suitable second carbon sources that enhanced the MEL yield with soybean oil as preferred primary substrate. After 10 days, a maximum yield of 75 g l(-1) was attained during shake-flask cultivation. Biofuel (rapeseed oil methyl ester) also resulted in high yields of MEL, but glucose reduced the MEL yield. Analysis by GC-MS showed that all fatty acids contained in MEL and derived from soybean oil or related methyl ester were degraded by C2-units to differing extents. The surface (water/air) and interfacial (water/hexadecane) tension of the MELs produced from different carbon sources were reduced to a minimum of 26.2 mN m(-1) and 1 mN m(-1), respectively.

Glycolipids↗

tBuP(NH2)2--a reactive synthon for the synthesis of molecular imidophosphinates of group 13 metals.

Reactions of tBuP(NH(2))(2) with Group 13 trialkyls MR(3) (M=Al, Ga, In; R=Me, tBu) were investigated in detail. According to variable-temperature (VT) NMR investigations, the reaction proceeds stepwise with the initial formation of aminophosphane adducts, which subsequently react to give iminophosphorane adducts and finally the heterocyclic metallonitridophosphinates. BP86/TZVPP (DFT) calculations were performed to verify this reaction pathway, to elucidate the influence of the central Group 13 element on the stability of the reaction intermediates and the heterocycles, as well as to assess the thermodynamics of their formation. The relative stability of free and complexed aminophosphane RP(NH(2))(2) and iminophosphorane R(H(2)N)(H)P=NH (adducts) with P(III) and P(V) centers was studied in more detail with DFT and MP2 methods. In addition, the influence of the substituent R was investigated by variation of R from H to Me, tBu, F, and NH(2). In general, the aminophosphane form was found to be favored for the free ligand, however, upon complexation with MR(3) (M=Al, Ga; R=alkyl) both forms are almost equal in energy.

Aluminum↗

[Is combined surgical correction of horizontal and vertical squint of value in graves' ophthalmopathy?].

BACKGROUND: In Graves' ophthalmopathy squint can be corrected in about two-thirds of the patients with a single recession of an inferior or medialis rectus muscle. The dose-effect correlation is linear over a wide range. Combined vertical and convergent misalignments are rare. The aim of this study was to evaluate the dose-effects in combined recessions of medialis and inferior rectus muscles. MATERIAL AND METHODS: The dose-effect of combined recessions (one side medialis and inferior n = 28, both sides medialis and one side inferior n = 9) was evaluated. The control groups were patients with Graves' ophthalmopathy, who had single inferior recession (n = 187), single medialis recession (n = 37) and bilateral medialis recession (n = 44). RESULTS: Small hypotropias (up to 5 degrees ) at the eye with the poorer abduction disappear after single (17 of 21) or bilateral (11 of 19) medialis recessions. This obvious influence of horizontal recession on the vertical angle leads to a higher dose-effect for the inferior recessions in combined surgery, and was stronger for bilateral cases (from 2.0 degrees to 2.7 degrees /mm recession) than for unilateral cases (from 2.0 degrees to 2.2 degrees /mm recession). The dose-effect for medialis recession in combined surgery increased for the unilateral procedures only from 1.7 degrees to 1.8 degrees /mm recession and not for the bilateral medialis recession. CONCLUSIONS: The dose-effect for combined medialis and inferior recessions is enhanced and varies to a much higher degree in comparison to single muscle recessions. Because of the higher variability, patients who need both medialis and inferior recession should be better operated in separate sessions, beginning with the horizontal muscle(s).

Adult↗

Immunohistochemical determination of somatostatin receptor subtypes 1, 2A, 3, 4, and 5 in various adrenal tumors.

While octreotide binds with high affinity to sst2a only, the new analogue SOM230 demonstrates high affinity for sstl, 3, and 5, in addition. We examined the immunohistochemical expression of somatostatin receptor subtypes (sst) in 7 pheochromocytomas (PHEO), 5 Conn adenomas (CONN), 9 Cushing adenomas (CUSH), 7 nonfunctioning tumors (NFA), and 4 adrenal carcinomas (CA). About one third of the PHEO were positive for sst1, 2a, and 5. Less than 30% of cells were stained in the majority of these tumors. Each of the PHEO expressed sst3 with more than 60% of cells stained. Two thirds of the NFA revealed positive staining for sst1, 2a, and 3 with less than 30% of cells affected. Sst5 was expressed in nearly all of the NFA with positive staining in 30-60% of tumor cells. Nearly all CUSH and CONN were positive for the subtypes evaluated. In the majority of these tumors, less than 30% of cells were positively stained. Fifty percent of CA expressed sst2a and 3 with positive staining in 30-100% of cells. None of them expressed sst1. Somatostatin receptors are expressed in adrenal tumors with a tumor-specific distribution pattern. This may offer new diagnostic and therapeutic possibilities.

Adenoma↗

Influence of O(3)/O(2)-pneumoperitoneum as an oxidative stressor on duration of anaesthesia, loss of different reflexes and cytokine mRNA expression.

We analysed the effect of intraperitoneal insufflated ozonized oxygen on the anaesthetic strength generated by tribromoethanol, ketamine/xylazine, chloral hydrate, pentobarbital, and urethane in male Wistar rats. High dosages of anaesthetic drugs normally used for deep surgical anaesthesia were injected. The ozonized oxygen gas mixture was given five times daily on five consecutive days at 0.8 mg ozone/kg body weight before anaesthesia. The reflexes were measured 15, 30, 60, 90, 120, 180, and 240 min after injection of the anaesthetic drug. The sleeping time and the loss and regain of six different reflexes on noxious and non-aversive stimuli were recorded during the 4 h of observation. O(3)/O(2)-pneumoperitoneum (O(3)/O(2)-PP) reduced the sleeping time induced by tribromoethanol and ketamine/xylazine and increased it for chloral hydrate and pentobarbital. In accordance to the changes in the duration of anaesthesia, the O(3)/O(2)-PP induced significant changes in the loss of different reflexes. Additionally, the modulatory effect of the anaesthetic drugs on splenic cytokine mRNA expression was further influenced by O(3)/O(2)-PP. Thus, the influence of an oxidative stressor on anaesthetic potency and on the resting immune system has to be taken into account for experimental designs in which surgical anaesthesia is necessary for small laboratory animals.

Analysis of Variance↗