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S Rupp

Publications and source records attributed to S Rupp.

At least 19 recordsLinked to original sources
PubMed2003

EFG1 is a major regulator of cell wall dynamics in Candida albicans as revealed by DNA microarrays.

Cell wall dynamics in Candida albicans, the most common fungal pathogen in man, underlie regulatory processes during the yeast-to-hyphae transition. To analyse this regulation at the transcriptional level, we have established a DNA microarray representing genes implicated in cell wall biogenesis. Using these microarrays, we were able to identify YWP1 and HWP2 that are specifically transcribed in the yeast or hyphal growth form respectively. Cluster analysis revealed at least two major clusters of genes: cluster I comprised genes that were upregulated under at least one hyphae-inducing condition. Three as yet not further characterized genes were attributed to cluster II. These genes were transcribed in the yeast form of C. albicans and were downregulated in an EFG1-dependent manner under specific hyphae-inducing conditions. We show further that, in contrast to CPH1, EFG1 plays a major role in the transcriptional regulation of cell wall proteins under the conditions investigated. EFG1 was essential for the transcription of both hyphae-specific genes such as HWP1 and HWP2 as well as the yeast form-specific gene YWP1. Moreover, we found that, under various conditions, EFG1 also can act as a strong repressor for the transcription of RBE1, another not yet characterized cell wall protein. Overall, our data show that EFG1 plays a major role in the induction and repression of cell wall genes, not only in the hyphal form but also in the yeast form of C. albicans.

Candida albicans↗
PubMed2003

A screen in Saccharomyces cerevisiae identified CaMCM1, an essential gene in Candida albicans crucial for morphogenesis.

Morphogenesis in Saccharomyces cerevisiae and the pathogenic yeast Candida albicans is governed in part by the same molecular circuits. In S. cerevisiae, FLO11/MUC1 expression has been shown to be modulated by multiple signalling pathways required for pseudohyphal development. We have established a screen in S. cerevisiae to identify regulators of fungal development in C. albicans based on FLO11::lacZ expression as a reporter. This screen identified both known components of the mitogen-activated protein kinase (MAPK) cascade and the cAMP cascade that are important for hyphal development in C. albicans, as well as genes not yet known to be involved in morphogenesis. The Candida homologue of MCM1 is one of the novel factors identified in this screen as being important for morphogenesis. CaMcm1p levels do not vary significantly in different cell types and respond to an autoregulatory feedback mechanism, arguing that CaMcm1p activity is regulated by post-translational modifications. Both overexpression and repression of this essential gene led to the induction of hyphae. Moreover, we found that the expression of HWP1, a hyphae-specific gene, was induced by repression of CaMCM1. The changes in morphology and HWP1 expression were not the result of a change in expression levels of NRG1 or TUP1, known repressors of hyphal development. Thus, CaMcm1p is a component of a hitherto unknown regulatory mechanism of hyphal growth.

Base Sequence↗
PubMed2003

[Biodegradable meniscus fixations: a comparative biomechanical study].

PURPOSE: Numerous new all inside meniscus repair techniques using biodegradable fixation devices have become available in the last years. Few studies have dealt with the biomechanical properties of these implants so far. The aim of this study was to analyze meniscus repairs under cyclic loading conditions for different fixation devices (Meniscus Arrow, Clearfix Meniscal Screw, Meniscal Dart, BioStinger) and to compare them to standard suture techniques. MATERIAL AND METHODS: Eighty meniscus repairs on 27 medial porcine menisci were performed. For biomechanical testing loosening, number of failures, failure modes and failure loads were evaluated under cyclic and maximum loading conditions. Testing was performed on a materials testing machine. RESULTS: During cyclic loading 10 out of 40 (25%) fixation devices failed. A gap appeared between the 2 parts of the meniscus within the first loading cycles. The failure strengths obtained with the 4 meniscus fixation devices did not differ significantly (Meniscus Arrow: 44 N; Clearfix Meniscal Screw: 35 N; Meniscal Dart: 33 N; BioStinger: 54 N). Besides for the BioStinger, the values of the sutures were significantly higher. The use of a stronger suture material (PDS 0) increased the failure load significantly. During maximum loading the fixation devices failed by both pull-out of the head or the tip of the device, except for the BioStinger showing only pull-out of the head. All sutures failed by breakage, except for the PDS 0 horizontal sutures in which 50% of complete tissue failures could be noted. CONCLUSION: This study shows that meniscal fixation devices may fail under repetitive loading conditions. A gap appeared between the meniscal margins within the first loading cycles irrespective of the suture type and fixation device used. Both gapping and failure modes of the fixation devices may be design-specific. The maximum failure loads differed significantly between the bioabsorbable devices and the sutures. Stronger suture materials increased the failure loads significantly. To allow a complete evaluation of new meniscus fixation devices not only biomechanical, but also biological and clinical parameters need to be analyzed in forthcoming studies.

Absorbable Implants↗
PubMed2002

[Replacement of the anterior cruciate ligament with a patellar tendon transplant].

The bone-patellar tendon-bone graft (BTPB) was the most commonly used graft for many years. The scientific database is more complete than for every other graft option. This review article presents the surgical techniques of ACL reconstruction with the BPTB graft, aspects of rehabilitation, clinical results, and postoperative problems with special emphasis on donor site morbidity.

Anterior Cruciate Ligament↗
PubMed2002

[Diagnosis of rupture of the anterior cruciate ligament].

Clinical examination has remained the key for diagnosis of meniscal and ligament lesions of the knee. Economical use of imaging techniques is based on adequate clinical examination. Standard radiographic examination is still a simple and valuable method. Magnetic resonance tomography has made great progress during the past few decades. For this reason, this article centers on this imaging modality.

Anterior Cruciate Ligament↗
PubMed2002

In vitro reconstructed human epithelia reveal contributions of Candida albicans EFG1 and CPH1 to adhesion and invasion.

The individual and synergistic contributions of two transcription factors, EFG1 and CPH1, have been characterized with regard to adhesion to, and invasion of, human epithelia by Candida albicans. For this purpose two in vitro reconstructed tissue models were developed. A multi-layered model of human epidermis was used to simulate superficial infections of the skin, whereas a reconstructed human intestinal model was used to mimic the first steps of systemic infections. It was shown that C. albicans deleted for both transcription factors CPH1 and EFG1, in contrast to the congenic clinical isolate Sc5314, was neither able to adhere to, nor to penetrate, either of the model systems. A strain deleted for EFG1 alone showed significant reduction in adhesion and was not able to penetrate through the stratum corneum. However, strains deleted for CPH1 showed phenotypes paralleling the phenotypes of the clinical isolate Sc5314. Using different types of multi-layered human tissues reconstructed in vitro the individual contributions of Efg1p and Cph1p to two important virulence factors of C. albicans, namely adhesion and invasion, could be defined.

Candida albicans↗
PubMed2001

[Effect of various suture strength factors on behavior of meniscus sutures in cyclic loading conditions].

The aim of this study was to analyze meniscal sutures under cyclic loading conditions for different suture types (vertical and horizontal mattress sutures) and suture materials (absorbable monofilament sutures: PDS 2-0; PDS-0, and PDS-1 USP). Testing was performed on medial porcine menisci, using a well-established biomechanical testing model with a complete longitudinal tear 3 mm from the periphery of the meniscus. Sixty specimens were used. One suture was tested at a time. During cyclic testing 100 load cycles were applied with a crosshead speed of 50 mm/min. Three different maximum loads (10 N, 20 N, and 40 N) were used. The preload was set at 5 N. After cyclic loading, the specimens were loaded until failure. During cyclic loading, a gap appeared between the two parts of the meniscus, and partial tissue failures were observed at the surface of the meniscus. Gapping was more marked with higher loads and with the weaker suture material (p < 0.001). Using PDS 0 and PDS 1 sutures, less partial tissue failures were observed compared to PDS 2-0 (p < 0.001). The ultimate failure loads after cyclic loading were higher with PDS-0 and PDS-1 sutures. With these suture materials vertical sutures were stronger than horizontal sutures (p < 0.05). Using PDS 2-0 this difference could not be found. These results show that the primary strength of meniscal sutures depends on the suture material. The frequency and the amount of gapping and partial tissue failures, which can be observed under cyclic loading, are less distinct with PDS-0 and PDS-1 compared to PDS 2-0. From a biomechanical point of view, PDS 0 and PDS 1 sutures are recommended for meniscal sutures to guarantee a high primary stability, a small amount of gapping, and few partial tissue failures.

Animals↗
PubMed2001

[Intermediate-term results after arthroscopic subacromial decompression with special reference to ongoing disability claims].

The objective was to evaluate mid-term results after arthroscopic subacromial decompression (ASD) with special focus on the bias due to an application to social insurance for pension based on sickness disability. The study group consisted of 42 patients (28 male, 14 female). ASD was performed in 1993 or 1994 for impingement stage II. The mean age was 49.5 years. Thirty-nine patients (93%) were evaluated by an independent observer for an average follow-up of 3.5 years (range 1.5-5). Patients satisfaction with the outcome was assessed by a visual analog scale graded from 0 (extremely dissatisfied) to 10 (extremely satisfied). The functional result was assessed using the Constant score. At follow-up the mean VAS value was 6.4 +/- 3.4. The Constant score improved from 49.6 +/- 18.5 to 84.8 +/- 14.3. The subgroup of patients having applied to social insurance for pension had significantly worse results compared with the remaining patients: VAS: 4.9 +/- 3.1 vs. 7.5 +/- 3.1; Constant-Score: 76.1 +/- 12.7 vs. 88.3 +/- 13.5. The fact that patients try to get benefit from social insurance based on sickness disability significantly biased the outcome after ASD.

Acromioclavicular Joint↗
PubMed2001

[Long-term results after excision of a popliteal cyst].

The objective was to evaluate long term results after removal of a popliteal cyst with special focus on recurrence rate and associated intraarticular pathology. Between 1982 and 1995 71 patients (23 women and 48 men between 21 and 75 years of age) underwent removal of a popliteal cyst. An additional arthroscopy of the knee joint was carried out in 51 consecutive patients starting in 1988. The mean follow up was 6.5 years (2 to 15 years), 66 patients (93%) were available. The subjective satisfaction with the outcome was assessed using a visual analogue scale (VAS) graded from 1 (highly satisfied) to 10 (highly dissatisfied). The popliteal region was evaluated by ultrasonography for recurrence of a cyst. During arthroscopy the predominant associated intraarticular pathologic finding was the lesion of the posterior horn of the medial meniscus (75%) and the lesion of the hyaline cartilage (90%). The cyst recurrence rate was 71%. In this subgroup grade III and grade IV chondral lesions were significantly more frequent (p < 0.001). Patients with a recurrence of the popliteal cyst rated the result significantly worse (7.6 +/- 2.3 vs. 3.4 +/- 2.3; p < 0.001). The recurrence rate was relatively high in the long term follow up. It depends strongly on the type of associated intraarticular pathology. Especially grade III and grade IV chondral lesions correlated significantly with recurrence of a popliteal cyst after removal. Therefore, the main goal of surgery should be the successful treatment of associated intraarticular pathologies.

Adult↗
PubMed2001

[Approach to open treatment of osteochondral lesions of the talus].

Arthroscopic techniques still represent the treatment of choice in osteochondral lesions of the talus (OLT). Open techniques may be used as an alternative or may be complementary to arthroscopic treatments. They are especially indicated in cases of large osteochondral lesions, difficult localisations and in cases of recurrent interventions. In addition to the type of treatment for the lesion itself, the choice of an ideal surgical approach is of paramount importance. Indications, operative technique, possible complications and rehabilitation are described in detail for each approach. Anterolateral, anteromedial, posterolateral and posteromedial soft-tissue approaches as well as medial and lateral malleolar osteotomies are discussed. If a distraction is not desired with arthroscopy, posteromedial and posterolateral soft-tissue approaches offer a good alternative for the treatment of posterior OLT. Osteotomy of the (medial) malleolus offers good visualisation of the medial talar dome. With the introduction of new techniques of osteochondral transplantations, the use of this approach is becoming more popular. However, it is an invasive technique and the risk of secondary osteoarthritis after malleolar osteotomy still needs to be determined.

Ankle Injuries↗
PubMed2001

[Biomechanical properties of interference screw implantation in replacement of the anterior cruciate ligament with patellar and hamstring transplants. An experimental study using roentgen stereometry analysis (RSA)].

This experimental roentgen stereometric analysis (RSA) study was performed to measure micromotions between the graft and tunnel under submaximal load in anterior cruciate ligament (ACL) reconstruction. The aim was to evaluate the maximum load at failure, linear stiffness, and slippage of bone-patellar-tendon-bone (BPTB) grafts fixed with interference screws compared to quadrupled hamstring grafts fixed with interference screws. We used 15 porcine tibia specimens for the study. In the BPTB group, the 10 x 25-mm bone plugs were fixed in a tunnel with 10 mm in diameter using a 7 x 25-mm titanium interference screw (n = 5) or a biodegradable screw (n = 5). The five hamstring transplants were folded to a four-stranded graft and armed with a baseball stitch suture. The sutured side was fixed with a 7 x 25-mm biodegradable polylactide screw in an 8-mm tunnel. The tibial bones, tendon grafts, and interference screws were marked with tantalum beads. The grafts were mounted to a custom made load frame and loaded parallel to the axis under RSA control increasing the force in steps of 50 N. Micromotions between bone plug, screw, and tibia were measured with RSA. Accuracy of RSA for the in vitro study was evaluated as 0.05 mm. Hamstring grafts failed at significantly lower maximum loads (492 +/- 30 N) than BPTB grafts (658 +/- 98 N). Linear stiffness of the hamstring graft fixations was eight times lower compared to the BPTB grafts (403 +/- 141 N/mm vs 3500 +/- 1300 N/mm). There was no significant difference between the biodegradable and titanium screws in the BPTB group. Slippage of the graft started at 82 +/- 35 N load in the hamstring group and at 428 +/- 135 N in the BPTB group. Slippage of the graft at 75% of the maximum pull-out strength was measured as 0.36 +/- 0.25 mm in the BPTB and 2.58 +/- 1.08 mm in the hamstring group. The interference screw fixation of a quadrupled hamstring graft showed a lower linear stiffness and an earlier slippage compared to a patellar tendon bone plug. Slippage of the hamstring grafts at submaximal loads may result in fixation failure during rehabilitation.

Animals↗
PubMed2001

Knee laxity after ACL reconstruction with a BPTB graft.

UNLABELLED: The objective of the study was to compare prospectively short-term and mid-term results after ACL reconstruction with special focus on changes in instrumented knee laxity. METHODS: The original study group included prospectively 58 patients who underwent arthroscopically assisted ACL reconstruction with BPTB graft in a two-tunnel technique between 1991 and 1993. Seven patients were lost to follow-up, leaving 51 patients for a first follow-up at 6 months and a second follow-up at 3-6 years (mean 4.3 years). Clinical results were evaluated by means of the Lysholm score and the IKDC score. Laxity was assessed using a KT-1000 arthrometer applying an 89 N anterior load in 20 degrees of flexion. Increased laxity was defined as a 3 mm increase in AP translation between the first and the second follow-up. RESULTS: At mid-term follow-up pivot shift was negative in 86% of cases. IKDC score: normal = 28%, nearly normal = 44%, abnormal = 24%, severely abnormal = 4%. KT-1000: < 3 mm = 68%, 3-5 mm = 24%, > 5 mm = 8%. The mean KT-1000 side-to-side difference was 1.08 (0.17) mm at 6 months and 2.01 (0.29) mm at 3-6 years. The difference was statistically significant (P < 0.005). According to the defined criteria, seven patients had increased laxity at the second follow-up, suggesting a malfunction of the graft due to stretch-out or injury. In this subgroup the mean KT-1000 measurements were 0.86 (0.26) mm at the first follow-up and 5.93 (0.54) mm at the second follow-up. In five of these patients, a malposition of the tunnels was identified as a possible cause. In the remaining group, KT-1000 measurements did not differ significantly between the first and the second follow-up [1.12 (0.20) mm versus 1.37 (0.21) mm]. CONCLUSIONS: Increase in AP laxity occurred in 14% of our cases between the first and the second follow-up. In most of these cases increased laxity was due to inadequate surgical technique, especially malposition of bony tunnels. If tunnel position was correct, there was no evidence for elongation of grafts over time as a general principle.

Adult↗
PubMed2001

Blood loss in anterior cruciate ligament (ACL) reconstruction with and without intercondylar notchplasty: does it affect the clinical outcome?

Blood loss is associated with any surgical procedure and should be reduced wherever possible. It was our impression that notchplasty adds to the amount of postoperative bleeding after anterior cruciate ligament (ACL) reconstruction. With posterior placement of the tibial tunnel, notchplasty is optional in many cases. This study aimed to quantify blood loss with and without notchplasty after arthroscopically assisted ACL reconstruction using bone-patellar tendon-bone autografts. We performed a prospective clinical study of 58 patients, who had undergone arthroscopically assisted autogenous patellar tendon ACL reconstruction. In group I, a notchplasty was necessary according to the local anatomical criteria (intraoperative impingement test). In group II, ACL replacement could be performed without notchplasty. Single and total day drainage volume, serum and suction drain hemoglobin (Hb) and hematocrit (Hct) levels were monitored. One year after surgery, the patients were reviewed to assess the outcome according to the IKDC and Lysholm scores and the KT-1000 arthrometer. The total drainage volume was 448 ml (range 150-550 ml) in group I and 299 ml (range 50-420 ml) in group II (p < 0.001). The serum hematocrit (Hct) decrease was 9.7% in group I and 7.4% in group II (p < 0.001). At 12 months after surgery, the IKDC and Lysholm score evaluations and the KT-1000 arthrometer measurements revealed no clinical differences between the notchplasty and non-notchplasty groups. Despite a 30% increase in blood loss, notchplasty has been shown to be a useful procedure to prevent graft impingement without negative side-effects.

Adult↗
PubMed2001

Fracture of the proximal tibia six months after Fulkerson osteotomy. A report of two cases.

The Fulkerson osteotomy has proved to be a reliable treatment for subluxation of the patella due to malalignment. Aggressive rehabilitation in the early postoperative period is unwise since the proximal tibia is weakened by the oblique osteotomy. Early weight-bearing and unrestricted activity have caused fractures in a few patients. Even late in the postoperative period the osteotomy may adversely influence the biomechanical properties of the proximal tibia. We describe two athletes who sustained a fracture of the proximal tibia, during recreational activities, six months after a Fulkerson osteotomy. Both had been bearing full weight for about ten weeks without complaint. Bony healing of the osteotomy had been demonstrated on plain radiographs at ten and at 12 weeks. After a Fulkerson osteotomy, jogging and activities which impose considerable impact force should be discouraged for at least nine to 12 months.

Adult↗
PubMed2000

A microarray enzyme-linked immunosorbent assay for autoimmune diagnostics.

In order to quantify autoantibodies in the sera of patients with autoimmune disease, we have created a microarray-based immunoassay that allows the simultaneous analysis of 18 known autoantigens. The microarrays contain serial dilutions of the various antigens, thereby allowing accurate determination of autoantibody titer using minimal amounts of serum. The assay is very sensitive and highly specific: as little as 40 fg of a known protein standard can be detected with little or no cross-reactivity to nonspecific proteins. The signal intensities observed from serial dilutions of immobilized antigen correlate well with serial dilutions of autoimmune sera. Miniaturized and highly parallelized immunoassays like these will reduce costs by decreasing reagent consumption and improve efficiency by greatly increasing the number of assays that can be performed with a single serum sample. This system will significantly facilitate and accelerate the diagnostics of autoimmune diseases and can be adapted easily to any other kind of immunoassay.

Antibodies, Antinuclear↗
PubMed2000

Evaluation of transarterial embolization for lower gastrointestinal bleeding.

INTRODUCTION: Transcatheter arterial embolization has been used as a therapeutic maneuver for lower gastrointestinal bleeding. The availability of highly selective arteriography has made this procedure safer and warrants re-evaluation. METHODS: A retrospective chart review was done of all patients undergoing arteriography for presumed lower gastrointestinal bleeding at two acute-care community hospitals. Causes of bleeding, clinical outcome, and complications caused by transcatheter arterial embolization were recorded. RESULTS: There were 26 arteriographically identified bleeding sites in the colon and small bowel. The most frequent cause of bleeding was diverticulosis (12 patients), with the diagnosis being arterio venous malformation in two, and one unknown colonic source. Transcatheter arterial embolization was attempted for 17 separate bleeding episodes in 16 patients. Transfusion requirements were an average (+/- standard deviation) of 7 +/- 1.43 units per patient. Transcatheter arterial embolization was successful in stopping bleeding in 14 cases (82 percent). Two patients had surgery after transcatheter arterial embolization: one for colonic necrosis and one for persisting bleeding. There were two more unsuccessful procedures; one had a successful repeated transcatheter arterial embolization, and one stopped spontaneously. One patient rebled during the same hospitalization and was controlled with intra-arterial vasopressin. There were two deaths, both secondary to sepsis unrelated to the transcatheter arterial embolization or the gastrointestinal tract. CONCLUSIONS: Transcatheter arterial embolization is a relatively safe and successful procedure in patients with massive lower gastrointestinal hemorrhage. It is an excellent choice of therapy for patients that are poor candidates for surgery, but its role in other patients remains to be defined.

Aged↗