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A Renner

Publications and source records attributed to A Renner.

At least 19 recordsLinked to original sources
PubMed2006

Efficacy of a strategy to prevent neonatal early-onset group B streptococcal (GBS) sepsis.

BACKGROUND: Existing guidelines recommend different strategies to prevent early-onset neonatal GBS sepsis. In 1997, using our own data on incidence and risk factors, we established a new prevention strategy which includes GBS screening at 36 weeks' gestation and intrapartum antibiotic prophylaxis (IAP) in women with positive or unknown GBS colonization with at least one risk factor. The present study evaluates the efficacy of the new prevention strategy. METHODS: Retrospective study of the incidence of early-onset GBS sepsis among all live births at the University Women's Hospital Basel between 1997 and 2002. Additional analysis of delivery and post partum period of all GBS sepsis cases, including GBS screening, risk factors during labor (prematurity, rupture of membranes (ROM) <12 h, intrapartum signs of infection), and IAP. Comparison of this group's characteristics G2 (9,385 live births, using the new strategy) with the previous group, G1 (1984-1993, 16,126 live births, without GBS screening or routine IAP) was performed. RESULTS: The incidence of early-onset GBS sepsis was reduced from 1/1000 (G1) to 0.53/1000 (G2). We observed a significant reduction of overall intrapartum risk factors in cases of GBS sepsis. CONCLUSION: This study suggests that our new prevention strategy is effective in reducing the incidence of early-onset GBS sepsis in neonates. In comparison, implementation of the CDC's prevention strategy might have prevented 2 additional cases in 9385 live births. However, this would have required treating a much larger number of pregnant women with IAP with consequential increasing costs, side effects and complications.

Antibiotic Prophylaxis↗
PubMed2004

[Late results after nerve transplantation on the upper extremities].

PURPOSE: The purpose of this retrospective study was to determine the influence of the type of injury, the time elapsed after the injury, the blood supply to the operation area, the size of the graft, and the applied treatment method on the late results. METHOD AND MATERIAL: In the study period from 1985 through 2000, nerve transplantations had been performed in 281 patients. There were 204 men and 77 women. Reconstructions were applied on the median nerve in 59 patients, ulnar nerve in 48, median and ulnar nerves in 23, radial nerve in ten, and digital nerves in 141 patients. 188 patients presented for late follow-up (66.9%). RESULTS: Evaluation was made according to the Highet scheme. In patients with median nerve transplantation M(3) or better results were seen in 69%, with M(3) being 45.2%. S(3) or better was observed in 64.3%, with S(3) being 47.6%. In patients after ulnar nerve transplantation M(3) or better result was achieved in 56.8%, M(3) being 19%. S(3) or better result was seen in 32.4%, S(3) being 27%. In patients who underwent median and ulnar nerve transplantations M(3) or better result was seen in 36.8%, M(3) being 26.3%. S(3) was in 42.1%, while S(4) did not occur. In patients after radial nerve transplantation M(3) or better effect resulted in 87.5%, M(3) being 12.5%. In patients with digital nerve transplantation S(3) or better result occurred in 57.4 %, S(3) being 47.6%. CONCLUSION: The best result can be achieved with nerve suturing, performed as an optimum from all aspects. However, as far as the surgical technique is concerned, results of using interfascicular grafts are more advantageous than epineural nerve suture based on compromises. In ideal circumstances, transplantation of a nerve graft less than 2 cm is of the same value as a good primary suture. If a nerve graft is longer than 2 cm, and negative local factors are accumulating due to the type of injury, late results will gradually deteriorating. The final outcome definitely depends on the patient's age and the time elapsed from the injury to the operation.

Adolescent↗
PubMed2001

Lipid hydroperoxides and free radical scavenging enzyme activities in preeclampsia and HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome: no evidence for circulating primary products of lipid peroxidation.

OBJECTIVE: Preeclampsia is reportedly accompanied by increased plasma lipid peroxidation. However, to date the assays that have been applied to measure lipid peroxides have been relatively nonspecific. A highly specific high-performance lipid chromatographic-chemiluminescence technique was used here to measure lipid hydroperoxides in plasma and red blood cells of patients with preeclampsia and HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome. STUDY DESIGN: Lipid peroxidation products, both lipid hydroperoxides and thiobarbituric acid reactive substances (TBARS), and free radical scavenging enzyme activities were measured in either plasma or erythrocytes of patients with normal pregnancies (n = 36), preeclampsia (n = 28), or HELLP syndrome (n = 10). RESULTS: Whereas lipid hydroperoxides were undetectable (<0.02 micromol/L), plasma TBARS and glutathione peroxidase activity in plasma and erythrocytes were significantly increased in patients with HELLP syndrome. There were no differences in glutathione transferase and reductase activities or superoxide dismutase activity between the groups. CONCLUSIONS: We were unable to corroborate results of studies that suggested that increased TBARS are representative of circulating plasma lipid hydroperoxides in preeclampsia. However, elevated glutathione peroxidase activity and TBARS are in line with increased oxidative stress in preeclampsia.

Adult↗
PubMed2000

High-throughput functional annotation of novel gene products using document clustering.

Gene products differentially expressed in healthy vs. diseased tissues may be considered drug targets since the change in their expression level can be related to the cause and progression of the disease studied. A significant portion of the proteins produced by these genes will be unknown and consequently their function must be characterised. The experimental elucidation of biochemical function must be supported by computational tools which can help predicting the possible function of a given protein from its amino acid sequence. We have designed a high-throughput system which automatically analyses amino acid sequences deduced from differentially represented cDNA clones. The system attempts to assign a biological function to protein sequences by carrying out searches in sequence databanks and by locating functionally relevant motifs in the query sequences. The results delivered by the various prediction methods consist of the annotations of matching sequences and/or motifs, which are free-format texts written by humans and therefore may describe the same concept with synonymous words. It is desirable to present the results in such a way that the annotations describing the same biological function are grouped together. To this end we devised an algorithm that enables the hierarchical clustering of free-format documents based on their contents. The system is capable of detecting and flagging conflicting annotations, and will speed up the interpretation of the function prediction results.

Algorithms↗
PubMed1999

Force field based conformational analysis of RNA structural motifs: GNRA tetraloops and their pyrimidine relatives.

The protocol of conformational analysis applied here to ribonucleotide oligomers combines conformational search in the space of torsion angles and energy minimization using the AMBER4.1 force field with a continuum treatment of electrostatic solute-solvent interactions. RNA fragments with 5'-GGGCGNNAGCCU-3' sequences commonly fold into hairpins with four-membered loops. The combinatorial search for acceptable conformations using the MC-SYM program was restricted to loop nucleotides and yielded roughly 1500 structures being compatible with a double-stranded stem. After energy minimization by the JUMNA program (without applying any experimental constraints), these structures converged into an ensemble of 74 different conformers including 26 structures which contained the sheared G-A base pair observed in experimental studies of GNRA tetraloops. Energetic analysis shows that inclusion of solvent electrostatic effects is critically important for the selection of conformers that agree with experimentally determined structures. The continuum model accounts for solvent polarization by means of the electrostatic reaction field. In the case of GNRA loop sequences, the contributions of the reaction field shift relative stabilities towards conformations showing most of the structural features derived from NMR studies. The agreement of computed conformations with the experimental structures of GAAA, GCAA, and GAGA tetraloops suggests that the continuum treatment of the solvent represents a definitive improvement over methods using simple damping models in electrostatic energy calculations. Application of the procedure described here to the evaluation of the relative stabilities of conformers resulting from searching the conformational space of RNA structural motifs provides some progress in (non-homology based) RNA 3D-structure prediction.

Base Sequence↗
PubMed1998

Unstable pelvic fractures in children.

A total of 3561 freshly injured children received treatment at the paediatric trauma department of the National Institute of Traumatology between 1984 and 1994. Out of these 38 (approx. 1%) had pelvic fractures. Based on the classification of Tile and Laer, 15 pelvic fractures were diagnosed to be unstable, from which 8 were polytraumatised, 4 shocked and 1 was a casualty. Run downs could be considered as the main cause of these fractures. Conservative treatment was provided for 13 unstable cases (bed rest: 5, band suspension: 1, femur skeletal traction: 4, femur traction and band suspension: 3). Surgery was performed in 2 cases (symphysis cerclage: 1, acetabulum plate o.s.: 1). Eleven patients were called in for late controls (after 3 years). Subsequent complications were: pain: 3, limb shortening: 4, lumbal scoliosis: 1, minor pelvic deformations: 4, partial necrosis of caput femoris: 2. The subjective complaints of 3 adolescent cases seem to be small in number, however, it is a fair assumption that the control period of 3-6 years later is not enough to form a comprehensive conception on the nature of early degenerative deformations occurring later, e.g. during adulthood. Because of further surgeries and examinations, correct traction and suspensional treatment can only be carried out with great difficulties regarding children. Therefore, posterior stabilisation of the pelvic ring must be planned with percutaneous sacroiliac pinning or screwing in unstable cases.

Accidents, Traffic↗
PubMed1998

[Possibilities for revascularization in early and late stage lunate malacia].

There are various biomechanical procedures for the treatment of lunate necrosis in the literature, but only a few deal with the possible revascularisation of the bone. We used the second dorsal metacarpal vascular bundle implantation technique in different stages of Kienböck's disease. Since 1990, twelve patients were treated by this method. In stage I-II according to Lichtman, we implanted the vessels in the lunate after excochleation and cancellous bone grafting, in stage III we used a modified form of the Graner operation and revascularised the proximalised part of the capitate. In the first group, six patients, we observed significant improvement in five cases clinically, radiologically confirmed stagnation of the process in four cases. In the second group of six patients, the clinical symptoms improved in four cases, three patients had to change work and one patient developed a pseudarthrosis between the capitate and corticocancellous block, but the proximalised part of capitate survived in all cases. Vascular bundle implantation can be a helpful method in early stages of lunate necrosis, helping to slow or to stop the progression of the disease.

Adolescent↗
PubMed1997

Orthodromic activation of peptidergic cells in the medial amygdala.

Electrical recordings from vasopressin-containing cells in the medial amygdala were obtained. Electrical stimulation of one major afferent structure, the accessory olfactory bulb, invariably elicited single unit discharge in the peptidergic cells and set up a field potential indicating widespread excitation in the structure. Pheromonal stimuli, normally borne into the brain by the accessory olfactory bulb, were ineffective in activating the medial amygdala. These results in combination with preexisting research suggest that the accessory olfactory bulb is an important influence, but not the only influence, on the activity of the peptidergic cells.

Action Potentials↗
PubMed1997

RNA structures and folding: from conventional to new issues in structure predictions.

Prediction and modeling of RNA structures has become an indispensable tool of biological research disciplines. Currently, reliable predictions require massive input of experimental data. Structure-forming elements are conventional base pairs, as well as a rapidly increasing repertoire of novel structural motifs. New developments extend structural analysis beyond the one-sequence/one-structure paradigm and allow questions that are relevant to molecular evolution to be answered.

Algorithms↗
PubMed1997

Density of states, metastable states, and saddle points exploring the energy landscape of an RNA molecule.

Detailed knowledge of the energy landscape of a biopolymer molecule is a prerequisite for understanding its folding kinetics and its final spatial structure. In the case of RNA we consider the energy landscape defined on the set of all secondary structures that can be formed by a given sequence. We show that the exploration of this energy landscapes is computationally feasible. For this purpose we present a recursive algorithm for computing the complete density of states and discuss its application to tRNA sequences. For shorter sequences a more detailed analysis of the energy surface is possible using a complete list of all secondary structures. In this case we identify metastable states and the saddle points that connect them.

Algorithms↗
PubMed1997

Exploring the fitness landscapes of lattice proteins.

We present methods to investigate the sequence to structure relation for proteins. We use random structures of HP-type lattice models as a coarse grained model to study generic properties of biopolymers. To circumvent the computational limitations imposed by most lattice protein folding algorithms we apply a simple and fast deterministic approximation algorithm with a tunable accuracy. We investigate ensemble properties such as the conditional probability to find structures with a certain similarity at a given distance of the underlying sequence for various alphabets. Our results suggest that the structure landscapes for lattice proteins are generally very rugged, while larger alphabets fine tune the folding process and smoothen the map. This implies a simplification for evolutionary strategies. The applied methods appear to be helpful in the study of the complex interplay between folding strategies, energy functions and alphabets. Possible implications to the investigation of evolutionary strategies or the optimization of biopolymers are discussed.

Algorithms↗
PubMed1997

[Microsurgical methods of bone replacement].

Vascularized bone grafting techniques are ideal for long bone defects in the extremities. The authors report on their experience in this field. From January 1991 to 2nd November 1995, 17 patients were treated by vascularized bone grafts. In ten cases iliac crest, in six cases fibula, and in one case a radial forearm composite flap was used. All patients have shown optimal healing and good bony consolidation, except for one case of circulatory disorder of the fibula graft.

Adult↗
PubMed1997

[Special epiphyseal injuries. 5 case examples].

In daily practice, the well-proved Salter-Harris-Rang epiphyseal injuries classification is used worldwide and in Hungary as well. Occasionally there are to be seen epiphyseal injuries which cannot be typed by this classification. The Ogden classification of epiphyseal injuries which enlarges the Salter-Harris-Rang classification with 6 subdivisions and 3 more subdivisions is very useful for the classification of such rare epiphyseal injuries. The authors focus one's attention on Ogden IIB type and Ogden VI type injuries on the basis of their own experience. Ogden IIB is often unstable and susceptible to shortening. In Ogden VI type ligamentous instability beside growing disturbance, caused by meta-epiphyseal bone bridge formation, can be seen. The comminuted growing plate injury caused by high energy direct trauma and healed without growing disturbance in their case, is missed in the Ogden classification. The proper classification is a necessary condition of adequate treatment. We recommend the Ogden classification of rare epiphyseal injuries.

Adolescent↗
PubMed1996

[Comparison between various treatment methods in scaphoid pseudarthrosis].

In this study we compare the results of various methods of treatment in 159 patients who were operated on between 1980 and 1990 for scaphoid pseudarthrosis at the Budapest Central Institute for Traumatology. Rated subjectively, 84% of the results of the Russe-I plasty were regarded as good, as were 75% of the spongiosaplasty, 88% of the Ender plate synthesis, and 75% of the AO navicular screw. Of the palliative methods retaining movement, denervation with styloidectomy yielded good results. Silicon prosthesis and proximal pole resection only led to temporary improvement. In patients with severe radiocarpal arthrosis who do heavy work, even today radiocarpal stiffening is regarded as the procedure of choice. In our experience, the best functional results can be expected when immobilization is as short as possible and fixation as stable as possible - which corresponds to Ender plate synthesis according to our results.

Adolescent↗
PubMed1995

Occult distal radial fractures.

The radiological diagnosis of distal radial fractures is usually easy, but some fractures without displacement cannot be detected at the first examination. In this retrospective study of 626 wrist injuries diagnosed as "wrist sprain" we found 39 distal radial fractures which were discovered only after repeated examinations. The incidence of distal radial fractures was much higher than other wrist fractures that were diagnosed after repeated examinations. Repeat standard four-view X-ray examination, as well as other imaging methods, are necessary to diagnose these fractures.

Adolescent↗