Biomedical subjects

M Ulrich

Publications and source records attributed to M Ulrich.

At least 19 recordsLinked to original sources

PubMed2001

[Selective pre- intra- and postoperative bile duct diagnosis--an efficient and low complication regimen within the scope of laparoscopic cholecystectomy. Early and late results of a prospective study].

INTRODUCTION: The discussion of diagnostic pre- and intraoperative procedures of the common bile duct (CBD) for laparoscopic cholecystectomy is still open. METHODS: Results of a prospective study of 4000 laparoscopic cholecystectomies were evaluated, adhering to the concept of selective common bile duct examination. In 1999 an inquiry was performed on 1197 patients an average of 38.7 months postoperatively to judge this concept. RESULTS: Three hundred and nineteen patients (8%) examined preoperatively by ERC revealing a CBD stone in 126 cases. The morbidity of this procedure was 3.1%. In 0.18% a lesion of the common bile duct was documented following laparoscopic cholecysTectomy. A intraoperative cholangiography was performed in 67 patients (1.7%) because of unclear anatomy or to exclude a CBD stone. Perioperatively a CBD stone was found in 0.5% of cases. Additionally, in 0.3% the same problem occurred in the long-term follow-up, so that the risk for unknown CBD stones following the selective diagnostic concept is 0.8%. CONCLUSION: The concept of selective diagnostic procedures of the common bile duct shows a low morbidity with sufficient efficiency in avoiding CBD stones as well as duct lesions. Therefore it is recommended for routine use in laparoscopic cholecystectomy.

Cholangiography↗

PubMed2001

Rapid D-dimer testing and pre-test clinical probability in the exclusion of deep venous thrombosis in symptomatic outpatients.

We assessed the performance of three rapid D-dimer tests (Auto Dimertest, VIDAS and Tinaquant) in combination with a pretest clinical probability model for deep venous thrombosis (DVT) in 106 consecutive outpatients with suspected DVT. Contrast venography or colour-coded duplex ultrasonography demonstrated the presence of DVT in 47 patients (14 distal DVT and 33 proximal DVT). First, we assessed the accuracy indices for different cut-off levels of the rapid D-dimer tests. Sensitivity was found to be 97.9-100%, negative predictive value (NPV) was 96.3-100%, and the exclusion rate was 24.5-31.1%. Next, the patients were grouped according to the pre-test clinical probability model in categories with low, moderate or high probability. In patients with a low pre-test probability, DVT would have been directly ruled out and the patients would not have undergone further investigations. In patients with a moderate probability, D-dimer testing and, in the case of a positive result, objective testing would have been performed and, in the case of a negative result, they would have been ruled out of having DVT. Patients with high probability would directly have undergone objective tests for DVT. The combination with the pre-test clinical probability model improved the exclusion rate (43.5-44.6%), whereas sensitivity (97.5-100%) and NPV (97.6-100%) remained roughly unchanged. The combination of rapid D-dimer tests with a pre-test clinical probability model may help to reduce unnecessary work-up in patients with suspected DVT.

Adolescent↗

PubMed2001

Anaerobic conditions induce expression of polysaccharide intercellular adhesin in Staphylococcus aureus and Staphylococcus epidermidis.

Products of the intercellular adhesion (ica) operon in Staphylococcus aureus and Staphylococcus epidermidis synthesize a linear beta-1,6-linked glucosaminylglycan. This extracellular polysaccharide mediates bacterial cell-cell adhesion and is required for biofilm formation, which is thought to increase the virulence of both pathogens in association with prosthetic biomedical implants. The environmental signal(s) that triggers ica gene product and polysaccharide expression is unknown. Here we demonstrate that anaerobic in vitro growth conditions lead to increased polysaccharide expression in both S. aureus and S. epidermidis, although the regulation is less stringent in S. epidermidis. Anaerobiosis also dramatically stimulates ica-specific mRNA expression in ica- and polysaccharide-positive strains of both S. aureus and S. epidermidis. These data suggest a mechanism whereby ica gene expression and polysaccharide production may act as a virulence factor in an anaerobic environment in vivo.

Aerobiosis↗

PubMed2001

Isolation of Leishmania infantum, zymodeme MON-1 from canine and human visceral leishmaniasis on Margarita Island, Venezuela.

An increase in the incidence of human visceral leishmaniasis (HVL) has been detected in recent years on Margarita Island, located off the NE coast of Venezuela. Recent studies have revealed reactivity to rK39 antigen (Leishmania chagasi) in 20% of 541 sera from domestic dogs in endemic communities; PCR reactions were positive using primers for the L. donovani complex. Here we report that isolates from human and canine infection, identified by isoenzyme analysis, correspond to L. infantum, zymodeme MON-1. This appears to be the first isolation and identification of an isolate from HVL on Margarita Island and demonstrates the presence of this zymodeme in the canine population.

Animals↗

PubMed2000

Chronic lithium and sodium valproate both decrease the concentration of myo-inositol and increase the concentration of inositol monophosphates in rat brain.

One of the mechanisms underlying lithium's efficacy as a mood stabilizer in bipolar disorder has been proposed to be via its effects on the phosphoinositol cycle (PI-cycle), where it is an inhibitor of the enzyme converting inositol monophosphates to myo-inositol. In contrast, sodium valproate, another commonly used mood stabilizer, appears to have no direct effects on this enzyme and was thus believed to have a different mechanism of action. In the present study, high resolution nuclear magnetic resonance (NMR) spectroscopy was used to study the chronic effects of both lithium and sodium valproate on the concentrations of myo-inositol and inositol monophosphates in rat brain. As predicted, lithium-treated rats exhibited a significant increase in the concentration of inositol monophosphates and a significant decrease in myo-inositol concentration compared to saline-treated controls. However, unexpectedly, sodium valproate administration produced exactly the same results as lithium administration. These novel findings suggest that both lithium and sodium valproate may share a common mechanism of action in the treatment of bipolar disorder via actions on the PI-cycle.

Animals↗

PubMed2000

Vaccine potential of poly-1-6 beta-D-N-succinylglucosamine, an immunoprotective surface polysaccharide of Staphylococcus aureus and Staphylococcus epidermidis.

Staphylococcus aureus and S. epidermidis are among the most common causes of nosocomial infection, and S. aureus is also of major concern to human health due to its occurrence in community-acquired infections. These staphylococcal species are also major pathogens for domesticated animals. We have previously identified poly-N-succinyl beta-1-6 glucosamine (PNSG) as the chemical form of the S. epidermidis capsular polysaccharide/adhesin (PS/A) which mediates adherence of coagulase-negative staphylococci (CoNS) to biomaterials, serves as the capsule for strains of CoNS that express PS/A, and is a target for protective antibodies. We have recently found that PNSG is made by S. aureus as well, where it is an environmentally regulated, in vivo-expressed surface polysaccharide and similarly serves as a target for protective immunity. Only a minority of fresh human clinical isolates of S. aureus elaborate PNSG in vitro but most could be induced to do so under specific in vitro growth conditions. However, by immunofluorescence microscopy, S. aureus cells in infected human sputa and lung elaborated PNSG. The ica genes, previously shown to encode proteins in CoNS that synthesize PNSG, were found by PCR in all S. aureus strains examined, and immunogenic and protective PNSG could be isolated from S. aureus. Active and passive immunization of mice with PNSG protected them against metastatic kidney infections after intravenous inoculation with eight phenotypically PNSG-negative S. aureus. Isolates recovered from kidneys expressed PNSG, but expression was lost with in vitro culture. Strong antibody responses to PNSG were elicited in S. aureus infected mice, and a PNSG-capsule was observed by electron microscopy on isolates directly plated from infected kidneys. PNSG represents a previously unidentified surface polysaccharide of S. aureus that is elaborated during human and animal infection and is a prominent target for protective antibodies.

Animals↗

PubMed2000

Trefoil factor family domain peptides in the human respiratory tract.

Trefoil factor family domain peptides (TFF) are thought to be involved in mucosal epithelial restitution and wound healing of the gastrointestinal tract and are up-regulated in ulceration and in a variety of solid tumours. It was hypothesized that TFFs are also expressed on mucosal surfaces of the human respiratory tract. Lung tissue, nasal polyps, and sputum samples from seven patients with cystic fibrosis (CF), two with chronic and acute bronchitis, and non-dysplastic material from two cases of bronchial adenocarcinoma were analysed for TFF expression by immunohistochemistry, immunofluorescence, western blot and RT-PCR. Expression of TFF1 and TFF3 was observed in material from all patients. TFFs were localized in goblet and ciliated cells, as well as in some submucosal cells of tracheobronchial tissues and nasal polyps from normal and CF individuals. In sputa of patients with CF and with chronic or acute bronchitis, TFF1 and TFF3 were detected by western blotting. Freshly cultivated nasal epithelial cells transcribed and secreted TFFs and mucins, whereas nasal cells cultivated for 6 weeks still expressed mucins, but not TFFs. Secreted TFFs and mucins also bound to the surface of Staphylococcus aureus in infected CF airways. In conclusion, TFF1 and TFF3 are expressed and secreted in normal and inflamed airways. The association of TFFs with bacteria may contribute to the anti-microbial mucociliary defence system.

Adenocarcinoma↗

PubMed2000

[Surgical therapy of colonic diverticulitis--how reliable is primary anastomosis?].

INTRODUCTION: The aim of the study was to evaluate the modern principles of surgery in diverticulitis, e.g. early elective resection and primary anastomosis. METHODS: The data of 445 consecutive patients were retrospectively analysed after classifying all cases in four subgroups according to a modified Hinchey classification (stages 0-III). RESULTS: Within our study group the morbidity was 26.5% (n = 118) and the mortality was 1.6% (n = 7). In 96% (n = 425) of all cases and in 64% (21/33) of patients with perforated diverticulitis and peritonitis (stage III), a primary anastomosis was performed. Four patients of the study group showed insufficient anastomosis (0.9%). No leakage was observed from any of the anastomoses performed in stage III diverticulitis. Stage of inflammation and age of patient correlate with morbidity and mortality. Some 53% (94/177) of the patients in stage II and 67% (22/33) of the patients in stage III had never showed symptoms of diverticulitis before. CONCLUSION: Prophylactic surgery to avoid life-threatening situations, including abscess formation or perforation, is not possible in many cases. However, especially patients at risk (age, coexisting illness) should undergo early surgery. Primary anastomosis can be performed safely even at an advanced stage.

Adult↗

PubMed2000

[Laparoscopic hernia therapy (TAPP) as a teaching operation].

INTRODUCTION: Because of an increasing number of endoscopic hernia procedures, it is important to look into the possibility of standardizing these techniques helping surgeons to acquire the operative skills necessary. MATERIAL AND METHODS: To discuss these aspects, the documented data on TAPP operations that have been carried out in this department since 1993 were analyzed. The results of teaching procedures were compared with those of experts after they had gotten past the learning and development curve. RESULTS: A total of 778 teaching procedures were performed by 10 surgeons with an individual experience of 30.5 operations (median). Before starting the first procedure, 89 were done by assistants operating the camera. The morbidity of teaching operations was 1.9% compared to 1.4% for those performed by experts. After a median follow-up of 23 months there were two recurrences (0.23%) in the expert group and none in the teaching group (follow-up 16 months). CONCLUSION: Because of the potentials of standardization of the TAPP technique, the results of teaching were equal to expert operations. Therefore, TAPP is suitable for application in a routine setting.

Clinical Competence↗

PubMed2000

Scrotal hernias: a contraindication for an endoscopic procedure? Results of a single-institution experience in transabdominal preperitoneal repair.

INTRODUCTION: Endoscopic repair was introduced for use with inguinal hernia therapy more than 10 years ago. The technique as well as the indications for this method are debated, however. As a borderline inguinal hernia situation, the scrotal hernia in particular evokes vehement objections to an endoscopic procedure because of the anticipated problems and complications in dissecting the extended hernia sac. The efficiency of the laparoscopic transabdominal preperitoneal (TAPP) technique in the treatment of scrotal hernia therefore is discussed in this article. METHODS: Laparoscopic hernia repair (TAPP) has been performed in our department since 1993. Data are collected by a prospective documentation of operative and follow-up results. For evaluation, a comparison of scrotal and normal hernia repair was performed. RESULTS: Between April 1993 and June 1998 the TAPP technique was used to treat 191 scrotal hernias, 42 (22%) of which were recurrent hernias. The median operating time for a normal inguinal hernia repair was 45 min, whereas scrotal hernias required a median of 65 min and irreducible scrotral hernias a median of 68.5 min. Major complications were observed in 1.6% of scrotal and 0.6% of normal inguinal hernia repairs. The most frequent scrotal hernia repair problem was the formation of a seroma, 10.5% of which had to be evacuated. During a follow-up period of 30 months, we found a total of two recurrences (1.05%). CONCLUSION: In scrotal hernia repair, TAPP is not associated with higher complication rates and can be performed with efficiency comparable with that in normal inguinal hernia repair.

Contraindications↗

PubMed2000

Recurrence after endoscopic transperitoneal hernia repair (TAPP): causes, reparative techniques, and results of the reoperation.

BACKGROUND: Even though the introduction of endoscopic surgical techniques to inguinal hernia therapy dates back 10 years, only a few data exist concerning the problem of development of a recurrence after endoscopic repair. Similarly there are only anecdotal reports on the feasibility of an endoscopic reintervention for this situation. For the first time we are able to present data of a prospective study on both issues. STUDY DESIGN: We analyzed the data of a prospectively documented series of 46 transperitoneal hernia repair reinterventions after endoscopic hernia repair. In 33 patients from our own clinic we evaluated the cause of recurrence after transperitoneal hernia repair. Together with these and 13 more patients sent to us from external clinics we examined the efficiency of an endoscopic reoperation. RESULTS: When implanting a 13 x 8-cm mesh with an incision (phase I) we found the main cause of recurrence to be that the mesh was too small (47.4%) and the region of the mesh incision was insufficient (42.1%). After a change to a 15 x 10-cm implant without incision (phase II) the main cause of recurrence was found to be a mesh dislocation (38.9%) and the rate of recurrence dropped from 2.8% (phase I) to 0.36% (phase II). The transperitoneal reoperation lasted for a median of 75 minutes (range 45 to 170 minutes) for the medial recurrence and a median of 110 minutes (range 65 to 190 minutes) for the lateral recurrence (p = 0.009). The total rate of complications was 10.9%, and the rate of re-recurrence was 0% after a median followup of 26 months (range 2 to 72 months). CONCLUSIONS: To avoid hernia recurrence after transperitoneal hernia repair operations a sufficiently large mesh (at least 15 x 10 cm) has to be implanted, preferably without an incision, after an extensive parietalization. The endoscopic reoperation for recurrence can be done only in a transperitoneal way and is effective with comparably low complication rates. The procedure is significantly easier for a medial recurrence compared with a lateral recurrence. This method of reoperation should be reserved for endoscopically experienced surgeons.

Adult↗

PubMed2000

Adherence of Staphylococcus aureus to endothelial cells: influence of capsular polysaccharide, global regulator agr, and bacterial growth phase.

The adherence of Staphylococcus aureus to human endothelial cells (EC) is probably an important step in the pathogenesis of systemic staphylococcal infections. We examined the influence of type 5 capsular polysaccharide (CP5) production, the global regulator agr, and the bacterial growth phase on S. aureus adherence to EC. Whereas S. aureus Newman showed maximal adherence to EC in the logarithmic phase of growth, an isogenic agr mutant showed maximal adherence in the stationary growth phase. S. aureus adherence to EC and CP5 expression were negatively correlated: a mutation in the agr locus diminished CP5 production and led to increased adherence. Likewise, induction of CP5 expression by addition of NaCl to the growth medium resulted in reduced staphylococcal adherence to EC. S. aureus Newman cells that adhered to EC did not express CP5. A Newman cap5O mutant was acapsular and showed significantly greater adherence to EC than the parental strain did (P<0.005). Complementation of the cap5O mutation in trans restored CP5 expression and reduced EC adherence to a level similar to that of the parental strain. The enhanced adherence shown by the cap5O mutant was similar in magnitude to that of the agr mutant or the cap5O agr double mutant. Cells of the cap5O mutant and cap5O agr double mutant harvested from stationary-phase cultures adhered significantly better than did cells harvested in the exponential growth phase. These data are consistent with the postexponential and agr-independent expression by S. aureus of at least one putative EC adhesin, whose binding domain may be masked by CP5.

Bacterial Adhesion↗

PubMed1999

Broadly protective vaccine for Staphylococcus aureus based on an in vivo-expressed antigen.

Vaccines based on preferential expression of bacterial antigens during human infection have not been described. Staphylococcus aureus synthesized poly-N-succinyl beta-1-6 glucosamine (PNSG) as a surface polysaccharide during human and animal infection, but few strains expressed PNSG in vitro. All S. aureus strains examined carried genes for PNSG synthesis. Immunization protected mice against kidney infections and death from strains that produced little PNSG in vitro. Nonimmune infected animals made antibody to PNSG, but serial in vitro cultures of kidney isolates yielded mostly cells that did not produce PNSG. PNSG is a candidate for use in a vaccine to protect against S. aureus infection.

Animals↗

PubMed1999

Laparoscopic hernia repair -- the facts, but no fashion.

BACKGROUND: For about 10 years now, laparoscopic hernia surgery has been introduced as an additional mode of therapy in the treatment of inguinal hernias. This method is being reproached with higher costs of surgery and rate of complications, as well as missing long-term results. MATERIALS AND METHODS: Within a literature research, data from 25 randomised trials and 16 prospective observational studies on endoscopic and conventional hernia surgery were evaluated. Statistics were calculated using the chi2 test. RESULTS: Compared with the conventional suture technique and tension-free surgery, the endoscopic repair proved to be advantageous with regard to postoperative pain and period of disablement. There was no significant difference between the methods when evaluating the rate of complications. In two randomised trials, there was a significant difference in favour of endoscopic repair with regard to the recurrence rates, whereas in the other studies a significant difference could not be shown. In the prospective series, recurrence rates were 0.71% for totally preperitoneal repair (TEP) and 1.06% for transabdominal preperitoneal repair (TAPP) repair. CONCLUSION: Endoscopic hernia surgery (TAPP and TEP) represents an efficient method of treatment in the therapy of inguinal hernias. Recurrent and bilateral hernias can be seen as an absolute indication for endoscopic repair.

Cost-Benefit Analysis↗

PubMed1999

In vivo analysis of dynamic tensile stresses at arterial end-to-end anastomoses. Influence of suture-line and graft on anastomotic biomechanics.

OBJECTIVE: to determine the influence of an anastomotic suture line and a graft on dynamic tensile stresses of vascular end-to-end anastomoses in vivo. MATERIAL AND METHODS: the abdominal aorta of twelve 35-kg pigs was used as an experimental model. Simultaneous recordings of internal arterial diameter and pressure were performed on each pig at 3 successive stages: (1) The genuine artery (REF), (2) artery-artery (A-A) and (3) graft-artery (G-A) anastomosis at 1-mm increments in the immediate perianastomotic area. Thereby, RD (relative distension), CC (compliance coefficient), E(p)(dynamic pressure-strain elastic modulus) and hysteresis loop areas could be calculated for every measuring point. RESULTS: the graft was significantly stiffer than REF. A-A and G-A anastomoses were significantly less compliant than REF. Maximum E(p), minimum CC and hysteresis loop areas were found at the anastomotic line due to minimum anastomotic RD. Downstream of the G-A anastomosis, the RD, CC, E(p)and loop areas were significantly different from REF, but significantly different from A-A. CONCLUSION: an animal model for acute studies of mechanical properties of vascular end-to-end anastomoses was developed. The main determinant for anastomotic biomechanics was the suture-line itself.

Anastomosis, Surgical↗

PubMed1999

Epidemiologic aspects of American visceral leishmaniasis in an endemic focus in Eastern Venezuela.

An endemic focus of American visceral leishmaniasis (AVL) in eastern Venezuela has been evaluated in terms of patients (n = 48), immunologic reactivity to Leishmania in household contacts (n = 187) and neighborhood controls (n = 170), detection of Leishmania (L. donovani complex) in dogs and wild animals by the polymerase chain reaction (PCR) and characteristics of the sandfly population. The male:female ratio of patients was 1.18:1; 89.6% were < or =12 years old. Serologic reactivity was significantly higher in household contacts than in controls (P = 0.0008), as was the size of leishmanin reactions in contacts < or =10 years of age (P = 0.0141). Leishmania donovani complex-specific PCRs were positive in dogs, an opossum (Didelphis marsupialis), and a black rat (Rattus rattus). Lutzomyia longipalpis and Lu. evansi, both implicated in the transmission of AVL, were identified among the 386 sand flies examined. These observations provide the bases for an active control program as well as further studies of reservoirs and vector-host relationships in this area.

Adolescent↗

PubMed1999

The influence of folic acid supplement on the outcome of pregnancies in the county of Funen in Denmark. Part I.

OBJECTIVE: To determine whether a supplement of folic acid given preconceptionally or early in pregnancy had any influence on, birth weight, incidence of preterm labour, low birth weight and small for gestational age. Furthermore, the aim was to elucidate, whether the outcome differed following the administration of two different dosages of folic acid, namely 2.5 and 1.0 mg. MATERIAL: All women in the childbearing age living on the island of Funen, Denmark (population 500,000) were offered a supplement of folic acid over a period of 3 years and 3 months. 14,021 women, who gave birth to 13,860 single-born and 325 multiborn children, were registered. A total of 8184 women took part in the double-blind randomized trial: 2310 had a supplement of folic acid without being randomized and 2721 women received no folic acid supplement. No information regarding the use of folic acid was available in 806 pregnancies. Abortions (512) were excluded. RESULTS AND CONCLUSIONS: A supplement 1.0 mg folic acid had the same effect as 2.5 mg. The effects of supplementing the diet with folic acid given preconceptionally or in the first half of pregnancy in an affluent Northern country were a slight increase of birth weight and a decrease in the incidence of preterm labour, infants with low birth weight and small for gestational age. The greatest effect was seen in the groups receiving folic acid preconceptionally.

Birth Weight↗

PubMed1999

The influence of folic acid supplement on the outcome of pregnancies in the county of Funen in Denmark. Part II. Congenital anomalies. A randomised study.

OBJECTIVE: The effect of folic acid supplement on the prevalence of congenital anomalies was studied in a Danish population. MATERIAL AND METHODS: From 1983 to 1986 all Danish women resident in the county of Funen were offered free folic acid when pregnant or planning a pregnancy. Folic acid dose was randomised to 2.5 or 1.0 mg. A randomised control group was not feasible for ethical reasons. Hospitals, midwives and most general practitioners cooperated to procure information on close to all pregnancies and congenital anomalies were recorded. RESULTS AND CONCLUSIONS: In a total of 14,021 pregnancies resulting in child birth 8184 women (58.4%) had folic acid with randomisation. Supplement was started in the randomised group before the last menstrual period in 1359/8184 (16.6%) and in the first 19 weeks of pregnancy in 6825/8184 (83.4%). The prevalence of congenital anomalies was 224 in 8293 children (27.0/1000). No dose-dependent differences were found in either total anomalies or in those specific malformations which have been reported to occur with reduced prevalence with periconceptional folic acid. The result was probably influenced by a start of supplement too late to affect malformation development in many cases and by the high level of both folic acid doses given compared to usual recommendations. Pregnancies without folic acid supplement showed prevalences similar to the supplemented groups.

Congenital Abnormalities↗