PubMed Health⌕ Search

Biomedical subjects

S Resch

Publications and source records attributed to S Resch.

At least 19 recordsLinked to original sources
PubMed2001

Decreased glomerular expression of agrin in diabetic nephropathy and podocytes, cultured in high glucose medium.

AIM: A decrease in glomerular heparan sulfate (HS) proteoglycan (PG), without apparent decrease in HSPG core protein expression, has been reported to occur in diabetic nephropathy (DN). In most studies however, agrin, the major HSPG core protein in the glomerular basement membrane, has not been studied. This prompted us to study the glomerular expression of agrin in parallel to the expression of HS-glycosaminoglycans (GAG) in biopsies of patients with DN. Furthermore, the influence of glucose on agrin production in cultured podocytes and the expression of agrin in fetal kidneys was investigated. METHODS: Cryostat sections of renal biopsies from patients with DN (n = 8) and healthy controls (HC, n = 8), were stained for agrin and HS-GAG. Sections of fetal kidneys were double stained for agrin and CD35 or CD31. Stainings were performed by indirect immunofluorescence (IIF). The production of agrin by cultured human podocytes was tested by ELISA and IIF. RESULTS: The expression of agrin, detected by AS46, was significantly reduced in biopsies from patients with DN compared to HC (p < 0.01). Similar findings were observed when monoclonal antibody JM72 was used (p < 0.05). In addition, a significant reduction in the glomerular expression of HS-GAG was detected with JM403 in these patients (p < 0.01). Agrin is expressed in cultured podocytes, the expression hereof was reduced when the cells were cultured in the presence of 25 mM D-glucose (p < 0.01). In biopsies of human fetal kidneys, glomerular expression of agrin coincided with the expression of CD31. In early stages of glomerular differentiation there was a strong staining for agrin and CD31 while CD35 was only slightly positive. CONCLUSIONS: Our data argue against a selective dysregulation in HSPG sulfation in DN, but suggest a pivotal role for hyperglycemia in the downregulation of agrin core protein production.

Aged↗
PubMed2000

Comparative studies in the promoter and exon 1 regions of tumour suppressor p53 in several mammalian species: absence of mutations in a panel of spontaneous domestic animal tumours.

Tumour suppressor p53 is critical in a broad panel of tumour types in human, mouse and other mammals. Regions of the promoter and exon 1 play an important role in expression of p53. In the present study, the DNA sequences of promoter and exon 1 regions of four domestic animal species (dog, cat, horse and cattle) are determined and compared with experimental rodents (mouse, rat and hamster) and man. A broad panel of tumour types have been investigated for mutations in this regulatory area in 90 canine, 136 feline, 25 equine and 10 bovine patients. No mutation was detected in any of the tumours analysed.

Animals↗
PubMed1999

Extended recombinant bacterial ghost system.

Controlled expression of cloned PhiX174 gene E in Gram-negative bacteria results in lysis of the bacteria by formation of an E-specific transmembrane tunnel structure built through the cell envelope complex. Bacterial ghosts from a variety of bacteria are used as non-living candidate vaccines. In the recombinant ghost system, foreign proteins are attached on the inside of the inner membrane as fusions with specific anchor sequences. Ghosts have a sealed periplasmic space and the export of proteins into this space vastly extends the capacity of ghosts or recombinant ghosts to function as carriers of foreign antigens. In addition, S-layer proteins forming shell-like self assembly structures can be expressed in candidate vaccine strains prior to E-mediated lysis. Such recombinant S-layer proteins carrying foreign epitopes further extend the possibilities of ghosts as carriers of foreign epitopes. As ghosts have inherent adjuvant properties, they can be used as adjuvants in combination with subunit vaccines. Subunits or other ligands can also be coupled to matrixes like dextran which are used to fill the internal lumen of ghosts. Oral, aerogenic or parenteral immunization of experimental animals with recombinant ghosts induced specific humoral and cellular immune responses against bacterial and target components including protective mucosal immunity. The most relevant advantage of recombinant bacterial ghosts as immunogens is that no inactivation procedures that denature relevant immunogenic determinants are employed in this production. This fact explains the superior quality of ghosts when compared to other inactivated vaccines. The endotoxic component of the outer membrane does not limit the use of ghosts as vaccine candidates but triggers the release of several potent immunoregulatory cytokines. As carriers, there is no limitation in the size of foreign antigens that can be inserted in the membrane and the capacity of all spaces including the membranes, peri-plasma and internal lumen of the ghosts can be fully utilized. This extended recombinant ghost system represents a new strategy for adjuvant free combination vaccines.

Adjuvants, Immunologic↗
PubMed1999

New strategies for combination vaccines based on the extended recombinant bacterial ghost system.

Controlled expression of cloned PhiX174 gene E in Gram-negative bacteria results in lysis of the bacteria by formation of an E-specific transmembrane tunnel structure built through the cell envelope complex. Bacterial ghosts have been produced from a great variety of bacteria and are used as non-living candidate vaccines. In the recombinant ghost system, foreign proteins are attached on the inside of the inner membrane as fusions with specific anchor sequences. Ghosts have a sealed periplasmic space and the export of proteins into this space vastly extents the capacity of ghosts or recombinant ghosts to function as carriers of foreign antigens, immunomodulators or other substances. In addition, S-layer proteins forming shell-like self assembly structures can be expressed in bacterial candidate vaccine strains prior to E-mediated lysis. Such recombinant S-layer proteins carrying inserts of foreign epitopes of up to 600 amino acids within the flexible surface loop areas of the S-layer further extend the possibilities of ghosts as carriers of foreign epitopes. As ghosts do not need the addition of adjuvants to induce immunity in experimental animals they can also be used as carriers or targeting vehicles or as adjuvants in combination with subunit vaccines. Matrixes like dextran which can be used to fill the internal lumen of ghosts can be substituted with various ligands to bind the subunit or other materials of interest. Oral, aerogenic or parenteral immunization of experimental animals with recombinant ghosts induced specific humoral and cellular immune responses against bacterial and target components including protective mucosal immunity. The most relevant advantage of ghosts and recombinant bacterial ghosts as immunogens is that no inactivation procedures that denature relevant immunogenic determinants are employed in the production of ghosts. This fact explains the superior quality of ghosts when compared to other inactivated vaccines. As carriers of foreign antigens there is no limitation in the size of foreign antigens to be inserted and the capacity of all spaces including the membranes, periplasma and internal lumen of the ghosts can be fully utilized. Using the different building blocks and combining them into the recombinant ghost system represents a new strategy for adjuvant free combination vaccines.

Adjuvants, Immunologic↗
PubMed1999

Results of flexor-to-extensor and extensor brevis tendon transfer for correction of the crossover second toe deformity.

Between 1990 and 1995, 38 patients (42 feet) underwent repair for crossover toe deformity, 31 (35 feet) of whom returned for final examination at an average of 51.6 months (range, 24-81 months). Causes included trauma, iatrogenic, and unknown. Presenting complaints included dorsal pain with either metatarsalgia or joint pain, isolated metatarsophalangeal (MP) joint pain, metatarsalgia, painful plantar callus, metatarsalgia and joint pain, and painful dorsal callus. All patients were treated with one of two operative techniques, either the flexor-to-extensor tendon transfer or the extensor brevis tendon transfer. Choice of procedure depended on the stage of preoperative deformity. Twenty-four patients were completely satisfied with the surgical correction, 6 were satisfied with reservations, and 1 was dissatisfied. The average postoperative AOFAS score for all patients was 85 points (range, 54-100 points), which correlated strongly with patient satisfaction. Twenty-two patients stated that they had no postoperative pain, 8 reported some pain, and 1 had frequent pain at the corrected toe. In 30 feet, there was no recurrence; three patients had mild residual crossover toe deformity, and two patients had recurrent deformity, although all MP joints were stable. Follow-up radiographs demonstrated substantial reduction in MP joint angles in both the AP (from 7 degrees to -1 degree) and lateral (from 45 degrees to 25 degrees) projections. This article reviews the surgical technique of both procedures, proposes specific indications for each, and presents outcomes. Based on our findings, the extensor brevis tendon transfer is appropriate for stage 1, stage 2, and flexible stage 3 deformities. Flexor-to-extensor tendon transfer is appropriate for rigid stage 3 and stage 4 deformities and for all patients with a symptomatic neuroma of the second web space (where the extensor brevis transfer is not possible). Stiffness of the MP joint is a potential problem with the flexor-to-extensor tendon transfer.

Adult↗
PubMed1998

Heterologous phi X174 gene E-expression in Ralstonia eutropha: E-mediated lysis is not restricted to gamma-subclass of proteobacteria.

E-lysis of Ralstonia eutropha H16, which belongs to the beta-subclass, was undertaken to verify whether transmembrane tunnel formation is possible in bacteria which do not belong to the enterobacteriaceae. For this purpose, a new gene E expression plasmid, pKG12, with two origins of replication, oriV and oriT, from plasmid pRP4, chloramphenicol and kanamycin resistance genes and a casette composed of lambda cI857 and lambda pR gene E was constructed. Temperature upshift of R. eutropha H16 (pKG12) from 28 to 45 degrees C during exponential growth resulted in lysis of the strain with features characteristic of E-mediated lysis of Escherichia coli. The cytoplasmic contents released can easily be separated from the still intact envelope fraction by centrifugation or filtration. As R. eutropha H16 represents an important industrial organism, E-mediated lysis could facilitate procedures for the recovery of intracellular mediators or products like polyhydroxyalkanoates.

Bacteriophages↗
PubMed1998

Aqueous release and purification of poly(beta-hydroxybutyrate) from Escherichia coli.

The poly(beta-hydroxybutyrate) (PHB) biosynthetic genes of Ralstonia eutropha that are organized in a single operon (phaCAB) have been cloned in Escherichia coli, where the expression of the genes in the wild-type pha operon from plasmid pTZ18U-PHB leads to the formation of 50-80% PHB/celldry mass when the cells are grown in Luria-Bertani medium supplemented with 1% glucose (w/v). In combination with the phaCAB genes, expression of cloned lysis gene E of bacteriophage PhiX174 from plasmid pSH2 has been used to release PHB granules produced in E. coli. It was shown that small PHB granules in a semiliquid stage are squeezed out of the cells through the E-lysis tunnel structure which is characterized by a small opening in the envelope with borders of fused inner and outer membranes. All envelope components remain intact after E-lysis and can be removed from the mixture of released PHB granules by density gradient centrifugation. In addition, a modified E-lysis procedure is described which enables the release of PHB from cell pellets in pure water or low ionic strength buffer. PHB granules in aqueous solution can be aggregated by divalent cations. Addition of glassmilk speeds up the agglomeration of PHB granules and binding to glass beads can either be used for collection or further purification of PHB in aqueous solutions.

Bacteriolysis↗
PubMed1998

Radiographic and clinical classification of acquired midtarsus deformities.

To develop a classification of midtarsus deformities, clinical examination and weightbearing radiographs were used to evaluate 131 feet in 109 patients (average age, 59+/-11 years) with those deformities. Patients were classified into four types based on anatomic location of the maximum deformity. Type I (N=43) showed deformity at the metatarsocuneiform joints medially and the fourth and fifth metatarsocuboid joints laterally, with plantarmedial and/or medial prominence. Type II (N= 60) had deformity at the naviculocuneiform joint medially and the fourth and fifth metatarsocuboid joints laterally; plantarlateral prominence was characteristic, although one-third had isolated or additional medial prominences. Type III (N=17) had major deformity in the perinavicular region, with a prominence plantarcentrally or plantarlaterally. Type IV (N=11) had deformity at the transverse tarsal joints with variable prominences. Each type was further subdivided into stages A, B, and C based on the severity of the deformity. In stage B, the midtarsus was coplanar with the metatarsocalcaneal plane. In stage A, the midtarsus was above this plane. In stage C, the midtarsus was below this plane. We concluded that midtarsus deformities can be classified as one of four types and one of three stages. Additional study is warranted to correlate this system with prognosis and treatment for this pathologic process.

Adult↗
PubMed1998

Preoperative traction for hip fracture: a randomized comparison between skin and skeletal traction in 78 patients.

153 consecutive patients with displaced cervical and trochanteric hip fractures were considered for inclusion in this study. 75 were excluded because of senile confusion and the remaining 78 were randomized to skeletal or skin traction preoperatively. The effect on pain alleviation was evaluated with a Visual Analogue Scale (VAS) and by the number of doses of analgesics administered. The processing time through the emergency department, radiographic department and to the ward, as well as time to operation, was registered. No significant difference in the VAS pain evaluation was found. There was a small significant increase in consumption of analgesics of no clinical importance in patients with skin traction, and no effect of traction type on the processing time or time to operation. Fracture type did not affect the outcome. Since half of the patients found the application of skeletal traction painful, compared to one fifth with skin traction, skeletal traction should not be routinely used to alleviate pain preoperatively in these patients.

Aged↗
PubMed1997

Molecular biology of S-layers.

In this chapter we report on the molecular biology of crystalline surface layers of different bacterial groups. The limited information indicates that there are many variations on a common theme. Sequence variety, antigenic diversity, gene expression, rearrangements, influence of environmental factors and applied aspects are addressed. There is considerable variety in the S-layer composition, which was elucidated by sequence analysis of the corresponding genes. In Corynebacterium glutamicum one major cell wall protein is responsible for the formation of a highly ordered, hexagonal array. In contrast, two abundant surface proteins from the S-layer of Bacillus anthracis. Each protein possesses three S-layer homology motifs and one protein could be a virulence factor. The antigenic diversity and ABC transporters are important features, which have been studied in methanogenic archaea. The expression of the S-layer components is controlled by three genes in the case of Thermus thermophilus. One has repressor activity on the S-layer gene promoter, the second codes for the S-layer protein. The rearrangement by reciprocal recombination was investigated in Campylobacter fetus. 7-8 S-layer proteins with a high degree of homology at the 5' and 3' ends were found. Environmental changes influence the surface properties of Bacillus stearothermophilus. Depending on oxygen supply, this species produces different S-layer proteins. Finally, the molecular bases for some applications are discussed. Recombinant S-layer fusion proteins have been designed for biotechnology.

ATP-Binding Cassette Transporters↗
PubMed1997

Bacterial ghosts as multifunctional vaccine particles.

Expression of cloned PhiX174 gene E in Gram-negative bacteria results in lysis of the bacteria by formation of an E-specific transmembrane tunnel structure built through the cell envelope complex. Bacterial ghosts have been produced from a variety of bacteria including Escherichia coli. Salmonella typhimurium, Salmonella enteritidis, Vibrio cholerae, Klebsiella pneumoniae, Actinobacillus pleuropneumoniae, Haemophilus influenzae, Pasteurella haemolytica, Pasteurella multocida, and Helicobacter pylori. Such ghosts are used as non-living candidate vaccines and represent an alternative to heat or chemically inactivated bacteria. In recombinant ghosts, foreign proteins can be inserted into the inner membrane prior to E-mediated lysis via specific N-, or C-, or N- and C-terminal anchor sequences. The export of proteins into the periplasmic space or the expression of recombinant S-layer proteins vastly extents the capacity of ghosts or recombinant ghosts as carriers of foreign epitopes or proteins. Oral, aerogenic or parenteral applications of (recombinant) ghosts in experimental animals induced specific humoral and cellular immune responses against bacterial and target components including protective mucosal immunity. The most relevant advantage of ghosts and recombinant bacterial ghosts as immunogens is that no inactivation procedures that denature relevant immunogenic determinants are employed in the production of ghosts used as vaccines or as carriers of relevant antigens. The inserted target antigens into the inner membrane or into S-layer proteins are not limited in size.

Adjuvants, Immunologic↗
PubMed1996

Presence of renin within intramitochondrial dense bodies of the rat adrenal cortex.

It has been suggested that tissue-specific expression of the genes of the renin-angiotensin system (RAS) leads to local generation of angiotensin (ANG) II with specific physiological implications. We demonstrate here that an intracellular RAS exists in adrenal glomerulosa cells; 60 h after bilateral nephrectomy and hemodialysis, renin and prorenin were eliminated from the circulation, whereas intra-adrenal renin content increased (control rats: 2 +/- 0.5 ng ANG I.mg-1.h-1; anephric rats: 25 +/- 2). Thus renin is produced locally within adrenal cells. We obtained immunocytochemical and biochemical evidence for the presence of renin within intramitochondrial dense bodies of the zona glomerulosa. After nephrectomy, dense bodies increased in number, size, and renin content (control rats: 2.5 +/- 0.7 ngANGI.mg-1.h-1; anephric rats: 43 +/- 7). Angiotensin-converting enzyme (ACE) was also present within mitochondria and their dense bodies. In addition, in adrenal cortex of anephric rats, giant dense bodies were observed, which contain renin and strongly react with an anti-angiotensinogen antibody. The localization of renin, ACE, and angiotensinogen at these sites provides new evidence for the existence of an intracellular adrenal RAS.

Adrenal Cortex↗
PubMed1996

Hallux valgus.

Explore the source record for details and available documents.

Hallux Valgus↗
PubMed1995

[Significance of serum troponin T in the differential diagnosis of myocardial infarct vs rhabdomyolysis vs renal insufficiency].

HISTORY AND FINDINGS: A 30-year-old man in renal failure due to focal sclerosing glomerulonephritis was, after a seizure with subsequent rhabdomyolysis, found to have an increase not only of creatinekinase (CK) activity (> 100,000 U/l) but also of cardiac troponin T (cTnT) concentration in serum (13 micrograms/l; normal: < 0.1 microgram/l), in the absence of any cardiac symptoms. COURSE: Raised concentration of cTnT is known to occur in patients with renal failure but no cardiac symptoms. In our patient, despite increased creatinine levels, serum cTnT gradually fell to normal within 3 weeks, i.e. the raised creatinine played no part in the elevation of cTnT, which in this patient was probably due to crossreaction between cardiac and skeletal TnT, or transient fresh synthesis of cTnT in regenerating skeletal musculature. CONCLUSIONS: In patients with extensive rhabdomyolysis and renal failure the assessment of the clinical status and the ECG, to exclude myocardial infarction, are of crucial importance. The cTnT level by itself is of only limited value in such cases.

Adult↗
PubMed1995

Parallel regulation of constitutive NO synthase and renin at JGA of rat kidney under various stimuli.

Four chronic experiments were performed to assess changes in the activity and gene expression of type I nitric oxide synthase (NOS) at the macula densa (MD) and of renin expression and immunoreactivity (IR) at the juxtaglomerular apparatus (JGA) of rat kidney, as follows: 1) two-kidney, one-clip Goldblatt hypertension (2K1C, for 3 and 40 days; sham operation for controls), 2) furosemide treatment (150 mg/kg-1.day-1 ip for 5 days), 3) chronic low-salt diet (0.02%) vs. high-salt diet (3%; both for 11 days), and 4) chronic blockade of NOS by nitro-L-arginine methyl ester (L-NAME, 40 mg.kg-1.day-1 for 2 mo). NOS and renin gene expression, NOS enzyme activity and renin IR were semiquantitatively evaluated with histochemical methods (NADPH diaphorase, in situ hybridization, immunohistochemistry). In 2K1C, marked increases were induced in NOS and renin in the ischemic vs. contralateral kidneys both after 3 and 40 days, respectively (P < 0.05). Related to controls, significant increases in the ischemic kidney were encountered after 3 and 40 days, whereas contralateral suppression of NOS and renin was found only after 40 days. Furosemide treatment resulted in a marked increase of both NOS and renin levels compared with controls (P < 0.05). Salt restriction induced a significant elevation of NOS levels compared with salt loading (P < 0.05), whereas only minor changes were evident in renin levels. L-NAME treatment resulted in a moderate reduction of NOS activity (not significant), whereas renin levels were markedly reduced (P < 0.05). These results show that NOS activity and gene expression are inversely related to chronic changes in renal perfusion, salt balance, and salt transport at the distal tubule in parallel with the known response of renin to these changes. Inhibition of NOS decreases renin levels at the JGA. The histochemical findings support previous concepts that MD-derived NO is involved in the control of renin synthesis.

Animals↗
PubMed1995

Measuring hallux valgus: a comparison of conventional radiography and clinical parameters with regard to measurement accuracy.

To assess the repeatability and error of conventional x-ray measurements, intra- and interobserver evaluations of measurement accuracy were done on 20 preoperative and 40 postoperative (20 chevron and 20 proximal osteotomy) x-rays of hallux valgus patients. Standard x-rays showed an average interobserver error of measurement of 6.4 degrees for the hallux valgus angle, 5.4 degrees for the intermetatarsal angle, and 2.0 mm for the intermetatarsal distance. The intraobserver error did not differ greatly. The repeatability and error of two clinical measurements, ball circumference, and dorsal to plantar range of motion of the first metatarsophalangeal joint were evaluated for 20 healthy volunteers. The ball circumference had an average measurement error of 1.1 cm, whereas the dorsal and plantar range of motion of the great toe had an average measurement error of 12 degrees in dorsiflexion and 16 degrees in plantarflexion. In both clinical and radiographic parameters, linear measurements were more accurate than angular measurements. Although x-rays are of value in hallux valgus surgery, standard x-rays are less accurate than previously assumed. Small changes produced by osteotomies may be hidden by the postoperative measurement error. The results of hallux valgus surgery should primarily be evaluated clinically. When clinical and radiological evaluations are made, linear measurements may be preferable.

Female↗
PubMed1995

Measurement of the forefoot with roentgen stereophotogrammetry in hallux valgus surgery.

Eight hallux valgus patients were marked with tantalum markers in conjunction with hallux valgus surgery (seven proximal osteotomies and one chevron osteotomy). Changes on weightbearing before surgery as well as corrective changes after surgery were analyzed with roentgen stereophotogrammetry (RSA) and with standard x-rays. RSA is accurate to 0.6 degrees in rotational changes and 0.3 mm in translation. Weightbearing changes were inconsistent, and minimal with both standard x-rays and RSA. It was possible to analyze the correction at the osteotomy site with RSA. In half the cases, the correction measured by RSA corresponded with that measured with standard x-rays, within measurement error; in the other cases, RSA showed that the correction was of a different size or direction than that measured on standard x-rays. Corrective changes in hallux valgus surgery are complex, including angular and translational changes at several levels and in several joints in order to produce a clinical resultant. Rotational changes can be evaluated with RSA. Although RSA in an optimal situation is very accurate, it is still limited to a laboratory setting.

Female↗