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Biomedical subjects

M Zellner

Publications and source records attributed to M Zellner.

18 recordsLinked to original sources

[Structure and process quality of inpatient urologic rehabilitation].

Inpatient rehabilitation and "Anschlussheilbehandlung" (rehabilitation soon after operation or acute intervention) are effective and economic for long-term improvement of urologic patients. Only therapy guided by urologic specialists during rehabilitation and afterwards guarantees the possibility of excellent results. Especially QOL and functional deficits are improved markedly by urologic rehabilitation. Therefore, inpatient urologic rehabilitation should be initiated more often in the future.

Combined Modality Therapy↗

[Urinary diversion after cystectomy: aspects of quality of life and options for rehabilitation].

Radical cystectomy in combination with different types of continent and incontinent urinary diversion is an integral part of the treatment concept for bladder tumors. Although in principle this operation does not cause disability in general, it represents a potentially massive encroachment on the physical and psychological integrity of the individual. The term "quality of life" appears with increasing frequency in modern concepts of evidence-based medicine. Also recognition of the subjective assessment of treatment by those affected in comparison to the "objective" view of qualified doctors and functionaries has become more relevant.Nevertheless, few studies have analyzed the "quality of life" after cystectomy. In addition, methodological factors hinder comparability. Only a few authors have used validated measuring instruments that allow comparison of the data. Low case numbers limit the statistical significance. Besides typical postoperative consequences and their effect on quality of life, potential influences on the pre- and postoperative assessment in the intraindividual course are discussed. The authors argue in favor of postoperative urological rehabilitation in qualified urological centers to optimize physical and psychological coping with the new life situation of "cystectomy with urinary diversion."

Adaptation, Psychological↗

Cell type-specific variations in the induction of hsp70 in human leukocytes by feverlike whole body hyperthermia.

Fever has been associated with shortened duration and improved survival in infectious disease. The mechanism of this beneficial response is still poorly understood. The heat-inducible 70-kDa heat shock protein (Hsp70) has been associated with protection of leukocytes against the cytotoxicity of inflammatory mediators and with improved survival of severe infections. This study characterizes the induction of Hsp70 by feverlike temperatures in human leukocytes in vitro and in vivo. Using flow cytometry, Hsp70 expression was determined in whole blood samples. This approach eliminated cell isolation procedures that would greatly affect the results. Heat treatment of whole blood in vitro for 2 hours at different temperatures revealed that Hsp70 expression depends on temperature and cell type; up to 41 degrees C, Hsp70 increased only slightly in lymphocytes and polymorphonuclear leukocytes. However, in monocytes a strong induction was already seen at 39 degrees C, and Hsp70 levels at 41 degrees C were 10-fold higher than in the 37 degrees C control. To be as close as possible to the physiological situation during fever, we immersed healthy volunteers in a hot water bath, inducing whole body hyperthermia (39 degrees C), and measured leukocyte Hsp70 expression. Hsp70 was induced in all leukocytes with comparable but less pronounced cell type-specific variations as observed in vitro. Thus, a systemic increase of body temperature as triggered by fever stimulates Hsp70 expression in peripheral leukocytes, especially in monocytes. This fever-induced Hsp70 expression may protect monocytes when confronted with cytotoxic inflammatory mediators, thereby improving the course of the disease.

Adult↗

Endothelial cells downregulate expression of the 70 kDa heat shock protein during hypoxia.

Hsp70 is induced by hypoxia in most mammalian cell types and contributes to their ability to survive hypoxic episodes. However, little is known about Hsp70 expression in the hypoxia-tolerant endothelial cells (ECs). We investigated the effect of hypoxia on Hsp70 in human microvascular endothelial HMEC-1 cells. Reduction of pO(2) to 2.5% of normal for 20 h stimulated lactate production and the activity of glycolytic enzymes. This metabolic adaptation to hypoxia was accompanied by a remarkable reduction of Hsp70 on the protein level and on the mRNA level. Approximately 12 h after the hypoxic period Hsp70 expression reached pre-hypoxia levels again. Since ECs are adapted to the low oxygen tension of the vasculature they are confronted with a supraphysiological oxygen level during in vitro culture. We suppose that the high Hsp70 under these conditions reflects a stress response which disappears at the more physiological reduced oxygen tension during hypoxia.

Atmosphere Exposure Chambers↗

Granulocyte colony-stimulating factor (G-CSF) downregulates its receptor (CD114) on neutrophils and induces gelatinase B release in humans.

Despite the increasing use of granulocyte colony-stimulating factor (G-CSF) for the mobilization of stem cells and neutrophils, its pharmacodynamic actions are not fully understood. Because of the roles of G-CSF and gelatinase B in leucokinetics, we set out to characterize the interaction of G-CSF with its receptor in humans and its effects on gelatinase B release. G-CSF was infused at bolus doses of 1 microg/kg and 5 microg/kg, and compared to placebo and dexamethasone (1 mg/kg b.i.d), which enhances the plasma levels of endogenous G-CSF. The study was randomized, double-blind, four-way crossover, in eight healthy male volunteers. G-CSF dose-independently induced profound neutropenia (> 95%) within minutes and downregulated its own receptor (CD114) on neutrophils by 75%. The G-CSF/CD114 interaction dose-independently induced degranulation of neutrophils as evidenced by a 300-400% increase in CD11b expression. Degranulation induced up to a 10-fold increase in plasma levels of gelatinase B, an enzyme known to precipitate neutropenia and subsequent neutrophilia in animals. In this study, it was shown that G-CSF downmodulates CD114 expression on the surface of neutrophils in humans and the consequent degranulation enhances gelatinase B release into plasma, which may contribute to mobilization of neutrophils or stem cells.

Antigens↗

Safety issues of plateletpheresis: comparison of the effects of two cell separators on the activation of coagulation, fibrinolysis, and neutrophils and on the formation of neutrophil-platelet aggregates.

BACKGROUND: Although many donors undergo repeated plateletpheresis, data on the consequences of plateletpheresis for the donor's health remain scarce. Thus, the effect of plateletpheresis on the activation of coagulation, fibrinolysis, and neutrophils was investigated. STUDY DESIGN AND METHODS: Part 1: Sixteen healthy men were randomly assigned to undergo plateletpheresis on a cell separator (AMICUS, Fenwal Baxter; or MCS 3p, Haemonetics). The effects of plateletpheresis on plasma levels of prothrombin fragment (F(1+2)), D-dimer, plasmin-plasmin inhibitor (PPI) complexes, and plasminogen activator inhibitor (PAI-1); on the activation of neutrophils (% L-selectin+); and on the frequency of platelet-neutrophil aggregates (% CD41+ neutrophils) were compared. Part 2: Ten healthy men received infusions of ACD-A and placebo without apheresis in a randomized, double-blind crossover study to control for the pharmacologic effects of citrate. RESULTS: Part 1: No change in F(1+2) occurred (p>0.05), which indicated that plateletpheresis did not enhance coagulation. Levels of D-dimer, PPI, and PAI-1 decreased over time on the AMICUS (p<0.001). Plateletpheresis did not activate neutrophils (p>0.05), but it decreased the percentage of CD41+ neutrophils (p<0.003). An approximately 80-percent drop in mononuclear cells was observed in the extracorporeal circulation of the AMICUS (p<0.001 vs. baseline and p = 0.005 vs. MCS 3p), and circulating lymphocyte and monocyte counts decreased concomitantly. Part 2: Infusion of ACD-A slightly decreased D-dimer levels (p<0.05), and both infusions decreased the circulating lymphocyte counts. CONCLUSION: Plateletpheresis can be regarded as safe with respect to the activation of coagulation or neutrophils. The consequences for the donor's health of the decrease in D-dimer, PPI, and PAI-1 may deserve further investigation.

Adult↗

Influence of heat shock on cell volume regulation: protection from hypertonic challenge in a human monocyte cell line.

Heat shock response provides cells with higher tolerance against a variety of insults such as heavy metals, reperfusion injury, and endotoxin. In addition, heat treatment is known to affect ion transport mechanisms associated with vital cellular processes, including cell volume regulation. However, there has been no reports to date of a heat shock effect on cellular volume regulation itself. The aim of our study was to investigate whether the heat shock response influences volume regulation of cells. Human promonocytic U937 cells display an increase in volume in response to osmotic shrinkage. This regulatory volume increase (RVI) is mediated mainly by ion antiporters. U937 cells exposed to a temperature of 45 degrees C for 10 min (heat shock) show an enhancement of RVI after hypertonic challenge compared with untreated cells. Also, heat-treated cells display a lower intracellular pH (pHi) than untreated cells; similar control mechanisms are believed to be involved in regulating both pHi and RVI. In agreement with this, heat-shocked cells demonstrated increased activity of an HCO3(-)-independent/DIDS-sensitive pHi down-regulator, postulated to be a Cl-/HCO3- exchange. We suggest that heat shock-mediated RVI enhancement is at least partially mediated by an increased Cl-/HCO3- exchange. Our results indicate that heat shock of U937 cells activates a hitherto unknown cytoprotective effect that may help cells to overcome hypertonic challenge.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗

Treatment of gustatory sweating with botulinum toxin.

Gustatory sweating is an autonomic disorder that frequently occurs after parotid gland surgery. We investigated the action of intracutaneous injections of botulinum toxin (BTX) (1.0-2.0 mouse units/2.25-cm2 skin area) in 45 patients (mean age, 52 years) with gustatory sweating. The area of hyperhidrosis was determined by Minor's iodine test before and up to 24 weeks after the injection. The effect of BTX was assessed by measuring the hyperhidrotic area. The maximum BTX-induced reduction of gustatory sweating was seen at 7.4 +/- 4.5 days after injection. The area of sweating decreased from 17.6 +/- 8.6 cm2 before BTX to 1.3 +/- 1.6 cm2 after BTX (p < 0.0001). Half the patients rated gustatory sweating subjectively as completely abolished, and the remainder felt pronounced improvement. No toxic effects were observed. In none of the patients did hyperhidrosis recur over a 6-month follow-up. We conclude that BTX is a safe and effective treatment that can be recommended as the therapy of choice in gustatory sweating.

Adult↗

Identification of the active-site residues of the 3C proteinase of foot-and-mouth disease virus.

To identify the active-site residues of the 3C proteinase of foot-and-mouth disease virus (FMDV), we introduced mutations into the 3C coding region and examined the activity of mutant enzymes on various substrates. Based on alignment of FMDV 3C with other picornavirus 3C proteinases and with the trypsin family of serine proteinases, mutations were introduced at residues presumed to be part of the catalytic triad, involved in substrate binding, or present in nonconserved regions. Wild-type and mutant 3C proteins were expressed in Escherichia coli and tested for their ability to cleave synthetic substrates corresponding to different portions of the viral genome. Substitutions at His-46 (catalytic triad), Asp-84 (catalytic triad), or His-181 (substrate binding) produced enzymes unable to process P1, P2, or P3 substrates in trans, whereas a change in the conserved Asp-98 had no effect on enzyme activity. Substitution of Ser for Cys-163 (catalytic triad) yielded an enzyme that retained activity on some substrates, while a substitution of Gly at this position resulted in a completely inactive enzyme. The kinetics of trans processing of translation products from a transcript encoding the P1 and P2 coding regions and the 2C/3A cleavage site with wild-type 3C or a transcript encoding P1 with 3C mutants revealed that the order of cleavage was VP3-VP1, VP0-VP3, VP1-2A, 2C-3A, and 2B-2C. Mutations in 3C that resulted in a partially active enzyme were individually introduced into full-length FMDV cDNA and RNA transcripts were translated in a cell-free system and used to transfect cells. In all cases the virus that was rescued had reverted to the wild-type 3C codon.

3C Viral Proteases↗

Expression in Escherichia coli and purification of biologically active L proteinase of foot-and-mouth disease virus.

The foot-and-mouth disease virus (FMDV) Lb gene was cloned into bacterial expression vectors under the control of a T7 RNA polymerase promoter. The Lb protein was expressed in both an in vitro transcription-translation system and in Escherichia coli. In vitro expression of a construct containing the Lb gene fused to a portion of the VP4 and 3D genes demonstrated cis cleavage activity that could be blocked by the thiol protease inhibitor E-64. Lb expressed in E. coli was purified from the soluble fraction by metal chelation chromatography. Purified Lb had trans cleavage activity at the L/P1 junction and cleaved the p220 component of the cap-binding protein complex.

Aphthovirus↗

Identification of the active-site residues of the L proteinase of foot-and-mouth disease virus.

The foot-and-mouth disease virus (FMDV) leader (L) protein is involved in autocatalytic cleavage at the L/P1 junction and in the cleavage of translation initiation factor p220, a subunit of the cap-binding protein complex. It has been suggested that this proteinase has homology to the papain-like family of cysteine proteinases, and from this information, we have investigated the active-site residues by introducing specific mutations into the L gene. Mutations of Cys-23 to Ala or His-120 to Leu resulted in enzymes that lacked cis activity at the L/VP4 cleavage site, trans activity on a truncated L-P1 substrate, and p220 cleavage activity. Mutations of Cys-23 to ser or His-110 to Leu resulted in enzymes that retained some or all cis activity and had reduced p220 cleavage. These mutations were introduced separately into a full-length FMDV cDNA, and RNA transcripts derived from these cDNAs were translated in a cell-free system and transfected into cells. The C23S mutant inefficiently cleaved at the L/P1 junction and within P1, and virus obtained from transfected cells reverted to wild type. The H110L mutant cleaved the L/P1 junction almost as well as the wild-type enzyme, and virus recovered from transfected cells retained the mutation and displayed wild-type viral protein synthesis and host shut-off kinetics.

Animals↗

[Interstitial laser-induced coagulation of the prostate for therapy of benign hyperplasia].

Interstitial laser-induced coagulation (ILC) is a new, minimally invasive, procedure for the treatment of benign prostatic hyperplasia (BPH). It is based on the placement of special light guides in the prostatic tissue, either transurethrally or perineally. The radiation source is a Nd-YAG laser, which is active for 3 or 5 min per fiber placement, respectively, with the power reduced stepwise. The coagulation necroses caused shrink during follow-up, leading to a decrease in the obstruction. In 239 patients treated in this way the mean I-PSS-Score fell from 25.4 to 8.1 points and the quality of life index from 4.1 to 1.6, the urinary peak flow rate increased from 7.7 to 16.3 ml/s, the residual urine volume fell from 151 to 32 ml, and the mean prostate volume declined from 47.4 to 32.2 ml in the first 3 months of follow up; 9.2% of the patients required further treatment within 1 year because of persistent obstruction. The complication rate was low. Statistical analysis showed no factors allowing prediction of the outcome. ILC is an effective method with few side effects and complications, and it has a wide range of indications for all BPH patients.

Aged↗

Phylogenetic analysis of segment 10 from African horsesickness virus and cognate genes from other orbiviruses.

Utilizing the reverse transcriptase-polymerase chain reaction (RT-PCR) procedure, we have synthesized full-length copies of segment 10 from African horsesickness virus (AHSV) serotypes 1, 4 and 8. The genes were cloned, sequenced and compared with the sequence of the cognate gene from AHSV serotypes 3 and 9. Sequences were analyzed to assess evolutionary relationships among serotypes using cladistics. Based on this analysis the data support a close relationship between serotypes 4 and 9 and between serotypes 1 and 8 and a closer relationship of serotype 3 to the 4 and 9 group.

African Horse Sickness Virus↗

Quality of life in long-term survivors of orthotopic heart transplantation.

This study was designed to evaluate quality of life and life changes after heart transplantation in long-term survivors, to compare the patients' results with those obtained from healthy subjects of similar age, and to correlate quality of life with psychological and clinical variables. Questionnaires were mailed to all 43 adult German-speaking transplant patients operated between 1982 and 1986. Forty-one (95%) of this patient population completed the questionnaires; 52 controls answered those questions not addressing transplant-specific issues. 83% of the transplant patients versus 88% of the controls rated global quality of life as "good" or "excellent". Psychological affect and well-being were comparable in both groups. 70% of the transplant patients versus only 30% of the controls stated "to be bothered by symptoms". Despite that response, heart transplant recipients perceived postoperative life changes mostly as positive, although sexual function and professional situation had worsened in 34% and 41%, respectively. Global quality of life correlated best with job satisfaction (r = 0.65, p less than 0.01), satisfaction about health (r = 0.64, p less than 0.01), well being (r = 0.53, p less than 0.01), and everyday life function (r = 0.53, p less than 0.01), and correlated negatively with depression (r = -0.40) and physical symptoms (r = -0.36). The study shows that the subjective quality of life of long-term survivors after heart transplantation is similar to that of healthy individuals of the same age group. Thus, survival is certainly not the only indicator of success; aspects of quality of life must also be included in cost effectiveness and/or cost benefit considerations in transplantation policies.

Activities of Daily Living↗

Nucleotide and deduced amino acid sequence of the nonstructural phosphoprotein, NS2, of bluetongue virus serotype 17: comparison to two isolates of serotype 10.

The nucleotide sequence of bluetongue virus (BTV) serotype 17 segment 8 from North America (NA) coding for the nonstructural phosphoprotein, NS2, was determined. This segment contains 1125 base pairs and codes for a protein of 40,581 daltons containing 354 amino acids with a net charge of -8.5 at pH 7.0. The carboxyl terminal portion of the protein is very hydrophilic and has a high degree of potential alpha-helix. Serine is the major, if not the exclusive, phosphorylated amino acid residue and ten of the twenty serine residues present in NS2 are found in consensus phosphorylation sites. Comparison of the nucleotide sequence of BTV-17NA segment 8 with the sequence of BTV-10NA and BTV-10 South Africa (SA) revealed a greater degree of homology between different serotypes within the same geographical area, i.e., 17NA and 10NA, than between isolates of the same serotype located in different areas, i.e., 10NA and 10SA. The same homology relationship as above was found at the amino acid level.

Amino Acid Sequence↗

Antigenic comparison of the polypeptides of foot-and-mouth disease virus serotypes and other picornaviruses.

The cross-reactivity of proteins coded for by the seven serotypes of foot-and-mouth disease virus (FMDV) was assessed by reaction of infected cell lysates with polyclonal and monospecific antisera against the structural and nonstructural proteins of FMDV type A12 strain 119ab. It was shown that the homologous polypeptides from most serotypes are antigenically related. The least cross-reactivity occurred between VP1, VP3, and the protease (3C) of type A12 and South African Territories types 1 and 3. There was also a reduced degree of reactivity of A12 VP1 serum with VP1 from some A subtypes and the other serotypes. Comparison of FMDV proteins with polypeptides from other picornaviruses by a radioimmune binding assay revealed a low level of reactivity of antisera against some A12 polypeptides with encephalomyocarditis virus (EMCV) infected cell lysates but no reactivity with bovine enterovirus type 1 and swine vesicular disease virus infected cells. The same EMCV proteins were immunoprecipitated by the various reactive A12 antisera, but the reaction was abolished if the lysate from EMCV infected cells was denatured prior to immunoprecipitation.

Animals↗