Search PubMed⌕ Search

Biomedical subjects

C Schneider

Publications and source records attributed to C Schneider.

At least 37 records · Page 2Linked to original sources

Enhanced APOE2 transmission rates in families with autistic probands.

We have previously described linkage/association between reelin gene polymorphisms and autistic disorder. APOE also participates in the Reelin signaling pathway, by competitively antagonizing Reelin binding to APOE receptor 2 and to very-low-density lipoprotein receptors. The APOE2 protein variant displays the lowest receptor binding affinity compared with APOE3 and APOE4. In this study, we assess linkage/association between primary autism and APOE alleles in 223 complete trios, from 119 simplex Italian families and 44 simplex and 29 multiplex Caucasian-American families. Statistically significant disequilibrium favors the transmission of epsilon2 alleles to autistic offspring, over epsilon3 and epsilon4 (allele-wise transmission/disequilibrium test [TDT], chi2 = 6.16, 2 degrees of freedom [d.f.], P<0.05; genotype-wise TDT, chi2 = 10.68, 3 d.f., P<0.05). A novel epsilon3r allele was also discovered in an autistic child and his mother. Autistic patients do not differ significantly from unaffected siblings (allele-wise TDT comparing autistic patients versus unaffected sibs, chi2 = 1.83, 2 d.f., P<0.40, not significant). The major limitation of this study consists of our small sample size of trios including one unaffected sibling, currently not possessing the statistical power necessary to conclusively discriminate a specific association of epsilon2 with autism, from a distorted segregation pattern characterized by enhanced epsilon2 transmission rates both to affected and unaffected offspring. Our findings are thus compatible with either (a) pathogenetic contributions by epsilon2 alleles to autism spectrum vulnerability, requiring additional environmental and/or genetic factors to yield an autistic syndrome, and/or (b) a protective effect of epsilon2 alleles against the enhanced risk of miscarriage and infertility previously described among parents of autistic children.

Apolipoprotein E2↗

Daytime variation in performance and tiredness/sleepiness ratings in patients with insomnia, narcolepsy, sleep apnea and normal controls.

Daytime tiredness or sleepiness and deficits in cognitive performance are common complaints in sleep disordered patients. Till now there are few studies comparing patients from different diagnostic groups of sleep disorders in the same experimental protocol. We studied the time course of cognitive functions and subjective alertness in a parallel group design with four groups of patients [narcolepsy, untreated or treated obstructive sleep apnea (OSA), or psychophysiological insomnia] and a control group of subjects without sleep complaints. Each group consisted of 10 subjects, matched for age and gender. After a night with polysomnography, subjects were studied for 10 h from 08:00 hours to 18:00 hours at 20 min intervals under standardized environmental conditions. Four psychological tests were applied, (1) a critical flicker fusion (CFF) test to measure optical fusion threshold (alertness); (2) a paper-and-pencil visual line tracking test (selective attention); (3) a visual analog scale (VAS) for tiredness/sleepiness; and (4) the Tiredness Symptoms Scale (TSS), a 14 items check list. Each test session lasted for 8 min, followed by a 12 min pause. The level and time course of cognitive performance and self-rating data were analysed with hierarchical linear mixed effects models. Cognitive tests showed decrements in alertness and selective attention in untreated patients with insomnia, narcolepsy, and sleep apnea. Narcoleptic patients and untreated OSA had a lower CFF threshold than controls, and for narcoleptic patients the time course differed from that of all other groups. In the visual tracking test the performance of all groups of patients was worse compared with normal controls. Self-rated tiredness/sleepiness was significantly more pronounced in the three groups of untreated patients than in control subjects.

Attention↗

Tumour suppression induced by the macrophage activating lipopeptide MALP-2 in an ultrasound guided pancreatic carcinoma mouse model.

BACKGROUND AND AIM: Carcinoma of the exocrine pancreas has a particularly poor prognosis. Therefore, novel therapeutic strategies such as immunotherapy are required. Here we investigated the immunomodulatory capacity of macrophage activating lipopeptide 2 (MALP-2), which binds to toll-like receptors 2 and 6 and induces activation of nuclear factor kappaB in monocytes. This causes the release of early stage leucocyte attracting chemokines and proinflammatory cytokines. METHODS: MALP-2 was tested in a new orthotopic ultrasound guided pancreatic cancer mouse model. This model is close to the biological situation and avoids the stress and immunostimulation caused by laparotomy. Cells from the syngeneic, highly aggressive, and metastatic cell line Panc 02 were administered orthotopically, by ultrasound guidance, to C57bl/6 mice. MALP-2 was administered intratumorally or intraperitoneally and tumour growth, immune status, and leucocyte infiltration at the tumour site were determined. RESULTS: We showed a tumour suppressive effect induced by a single injection of MALP-2. Median survival increased from 21 to 30 days (p<0.002). Combining chemotherapy (gemcitabine) with MALP-2 treatment caused further prolonged survival (median survival 27 days with chemotherapy alone v 37 days for combined treatment; p<0.0002). The life prolonging effect was paralleled by a significant increase in cytotoxic T cells, restoration of beta2 integrin expression on lymphocytes, and high expression of CD45RB on T helper cells. Immunohistochemical stains showed strong cytotoxic T lymphocyte and natural killer cell infiltration. CONCLUSIONS: In conclusion, in a model of orthotopic pancreatic cancer in mice, we induced a tumour suppressive effect by treatment with a synthetic lipopeptide. Treatment with MALP-2 could be an option for immunotherapy in pancreatic cancer.

Adenocarcinoma↗

Staging of colonic neoplasms by colonoscopic miniprobe ultrasonography.

BACKGROUND AND AIMS: In contrast to the situation in the upper gastrointestinal tract staging of colonic neoplasm by endoscopic ultrasonography (EUS) has not gained importance because until yet preoperative staging is without any clinical consequences. This may change with the introduction of minimally invasive surgical procedures and endoscopic resection techniques as an alternative to conventional (open) surgery. PATIENTS AND METHODS: We performed EUS with a miniprobe in 54 consecutive patients with colonic tumors who had been referred to our hospital for endoscopic resection or for laparoscopic resection of their lesions. Therefore patients with locally advanced tumors or systemic tumor spread were not included. After detection of the lesion during colonoscopy miniprobe EUS was performed with water-filling of the colonic lumen. The depth of invasion (T classification) and the local lymph node status (positive or negative) was ascertained. Lymph node-negative lesions staged as T1 underwent endoscopic resection whenever this was technically possible. In lymph node-negative T2-3 tumors laparoscopic resection was planned if they were localized at least 10 cm apart from the flexuras. All other lesions were resected by open surgery. The EUS findings were later compared with the final pathological results (pTN classification) of the resected specimen. RESULTS: In 50 patients (93%) a sufficient EUS evaluation of the colonic tumor was possible. In one patient with a tumor at the left flexura the lesion could not be completely visualized, and in three patients a sufficient water filling of the colon was impossible. The infiltration depth was correctly classified in 17 adenomas, 16 T1, 8 T2, 5 T3, and one T4-carcinoma (EUS accuracy for T staging: 94%). Two T2 and one T3 carcinoma were overstaged by EUS while no understaging was recorded. The lymph node status was correctly classified in 42/50 patients (84%), and a false-negative lymph node status was found in only 4/50 cases (8%). The overall accuracy of EUS was 80%. CONCLUSION: Miniprobe EUS is suitable and has a sufficient but not optimal accuracy for staging of colonic neoplasm. Its employment makes sense if minimally invasive resection techniques in patients with high-risk for open surgery are planned.

Adenoma↗

Totally extraperitoneal repair of recurrent inguinal hernia.

BACKGROUND: A variety of procedures with substantial differences in results are employed to treat recurrent inguinal hernia. The advantages of totally extraperitoneal patch repair (TEP) are even more evident when it is applied to recurrent compared to primary hernias. To investigate the superiority of this method more closely, we reviewed our results obtained for recurrent inguinal hernias over a period of 2 years. METHODS: We performed a prospective single-center study using data obtained in consecutive patients with recurrent inguinal hernia who were operated on in 1997 and 1998. RESULTS: A total of 179 patients with recurrent inguinal hernia were recruited. Overall, 1329 patients with inguinal hernia were treated in the 2-year period, of whom 1270 underwent TEP. The percentage of recurrent hernias was 14%. The average age of the patients was 56 years. The follow-up rate was 87.5%, and the mean follow-up period was 2.3 years. The 154 patients who were followed up underwent a total of 225 hernia repairs, of which 181 were for recurrent hernias. The average operating time was 57 min. In 68% (104/154) of the patients, adhesions, adherent epigastric vessels, or cicatricial changes were found, which resulted in the inadvertant opening of the peritoneum in 26.3% of the patients. All the openings in the peritoneum were closed by endoscopic suturing. Intraoperative complications developed in 4 patients (2.3%), including one injury to the bladder and three cases of bleeding from side branches of the epigastric vessels. The conversion rate was 0%. The sole postoperative complication was treatment requiring hematomas in 7 patients, in 2 of whom reoperation became necessary. In both cases, a diffuse hemorrhage due to a preoperatively undiagnosed coagulation disorder was found. No cases of wound or patch infection were observed. In a patient undergoing both primary and recurrent hernia repair, displacement of a mesh led to a recurrence on the primary hernia side (recurrence rate, 0.4%; re-recurrence rate, 0%). CONCLUSIONS: Although for its definitive management, recurrent hernia requires a reliable operative technique, current data do not support the recommendation of any of the currently available procedures as the gold standard. In a representative patient population with recurrent hernia, we were able to demonstrate that TEP achieves very good results in terms of re-recurrence rate, intraoperative and postoperative complications, and rehabilitation. Prerequisites for the reliable and low-complication application of the method are a high level of standardization of the procedure and an advanced learning curve.

Adolescent↗

Oncological quality and preliminary long-term results in laparoscopic colorectal surgery.

BACKGROUND: Our aim here was interpret data on the perioperative course, oncological quality, and preliminary long-term results of laparoscopic colorectal surgery carried out with a curative intent. METHODS: The data were collected within the framework of a prospective multicenter observational study that has been ongoing since 1 Aug 1995 and includes 46 hospitals. Of a total of 3133 patients, 826 (26.4%) underwent a curative resection for colorectal carcinoma. RESULTS: The average age of the patients was 67.9 years; the sex distribution was almost 1:1. UICC staging of tumors (stages I, II, and III) showed the following figures: 301/36.4%, 265/32.1%, and 260/31.5%. In the majority of cases, an oncologically radical resection with high transection of the supplying vessels was performed. Intraoperative seeding of tumor cells was reported in 1.8% of the patients. In eight cases, the seeding was due to spontaneous rupture of the tumor. A mean of 13.5 lymph nodes in the resected specimen were investigated histopathologically (10.9 lymph nodes in stage I, 15 each in stages II and III). Depending on the individual hospital, we found a remarkable variation in the number of lymph nodes investigated. With a mean follow-up period of 2.1 years, Kaplan-Meier survival function showed acceptable results, both for rectal and colonic carcinoma, in comparison with conventional colorectal surgery. A stage-related consideration of the survival data yielded similar results. CONCLUSION: All in all, the results show that a laparoscopic colorectal procedure can meet oncological radicality criteria, even though certain reservations-in particular, in the case of procedures done with a curative intent-have not been completely eliminated.

Aged↗

Myotonic dystrophy type 2: molecular, diagnostic and clinical spectrum.

BACKGROUND: Myotonic dystrophy types 1 (DM1) and 2 (DM2/proximal myotonic myopathy PROMM) are dominantly inherited disorders with unusual multisystemic clinical features. The authors have characterized the clinical and molecular features of DM2/PROMM, which is caused by a CCTG repeat expansion in intron 1 of the zinc finger protein 9 (ZNF9) gene. METHODS: Three-hundred and seventy-nine individuals from 133 DM2/PROMM families were evaluated genetically, and in 234 individuals clinical and molecular features were compared. RESULTS: Among affected individuals 90% had electrical myotonia, 82% weakness, 61% cataracts, 23% diabetes, and 19% cardiac involvement. Because of the repeat tract's unprecedented size (mean approximately 5,000 CCTGs) and somatic instability, expansions were detectable by Southern analysis in only 80% of known carriers. The authors developed a repeat assay that increased the molecular detection rate to 99%. Only 30% of the positive samples had single sizeable expansions by Southern analysis, and 70% showed multiple bands or smears. Among the 101 individuals with single expansions, repeat size did not correlate with age at disease onset. Affected offspring had markedly shorter expansions than their affected parents, with a mean size difference of -17 kb (-4,250 CCTGs). CONCLUSIONS: DM2 is present in a large number of families of northern European ancestry. Clinically, DM2 resembles adult-onset DM1, with myotonia, muscular dystrophy, cataracts, diabetes, testicular failure, hypogammaglobulinemia, and cardiac conduction defects. An important distinction is the lack of a congenital form of DM2. The clinical and molecular parallels between DM1 and DM2 indicate that the multisystemic features common to both diseases are caused by CUG or CCUG expansions expressed at the RNA level.

Adolescent↗

Potential device interaction of a dual chamber implantable cardioverter defibrillator in a patient with continuous spinal cord stimulation.

Spinal cord or thalamic deep brain stimulation with a pacemaker is becoming more important in the treatment of drug refractory pain due to peripheral vascular disease, angina pectoris and intractable tremor in patients with neurologic disorders such as Parkinson's disease. An additional indication for a cardiac pacemaker or implantable cardioverter defibrillator raises concerns about possible interactions between the implanted electrical devices. We report on a patient with existing spinal cord stimulation who survived sudden cardiac death and received a dual chamber cardioverter defibrillator capable of delivering tiered therapies in both the atrium and ventricle.

Aged↗

A European survey of diagnostic methods and testing protocols for Clostridium difficile.

OBJECTIVE: To conduct a survey of the methods used in clinical microbiology laboratories in Europe to diagnose infection with Clostridium difficile. METHODS: A questionnaire was devised and sent to a co-ordinating member of the Study Group in each of eight European countries. This co-ordinator was in charge of forwarding the questionnaire to hospital laboratories arbitrarily selected. The number of laboratories in each country was determined on the basis of one laboratory for 10,000 beds of hospitalization. This questionnaire covered different aspects pertaining to Clostridium difficile associated to diarrhea (CDAD) diagnosis such as circumstances of request, criteria used for undertaking C. difficile investigations, methods used for the diagnosis, etc. RESULTS: A total of 212 questionnaires were completed and submitted for analysis: 87.7% of laboratories reported routinely performing C. difficile diagnostic tests. Methods used included toxin detection (93%), culture (55%), and glutamate dehydrogenase (GDH) detection (5.9%). Among the laboratories detecting toxins, different enzyme immunoassays (EIA) and cytotoxicity assays were used in 79% and 17.3% of cases, respectively. Among the different strategies reported, 4.8% were considered suboptimal for the diagnosis of C. difficile infections, but marked discrepancies could be observed between countries. The overall incidence (median) of CDAD was estimated at 1.1 for 1,000 patient admissions. CONCLUSION: The results of this study suggest marked discrepancies between laboratories and also between countries regarding the criteria by which C. difficile is investigated for, and the methods and the strategies that are used for the diagnosis of C. difficile. These discrepancies could be explained by the lack of clear guidelines for C. difficile diagnosis in each country, and by the importance that physicians attach to C. difficile. Precise guidelines for C. difficile diagnosis would be the first step to make possible accurate comparison of the incidence and the epidemiology of CDAD from one hospital to another or from one country to another.

Bacterial Proteins↗

Mixed chimerism of erythro- and megakaryopoiesis following allogeneic bone marrow transplantation.

Until now, studies on mixed chimerism (MCh) after allogeneic bone marrow transplantation (BMT) have predominantly focused on the B- and T-lymphocyte population, but not on distinct myeloid cell lineages like nucleated erythroid precursors and megakaryocytes. To evaluate the lineage-restricted MCh more explicitly in 10 patients with chronic myelogenous leukemia (CML), a quantitative analysis was performed on bone marrow biopsies following a sex-mismatched host/donor constellation. Techniques included immunophenotyping (antiglycophorin C, CD61) for the identification of erythro- and megakaryopoiesis and a simultaneously conducted genotyping with x- and y-chromosome-specific DNA probes. Normal bone marrow and specimens taken before BMT served as controls. Contrasting a total gender-dependent sex-typing in the latter samples in the early and late posttransplant period (up to 586 days), 3-9% erythroid precursors and about 16% megakaryocytes revealed a host-type origin. This significantly higher number of host megakaryocytes is explained by their polyploidy generating an increased probability to detect positive signals at a certain section level of the corresponding biopsies. A striking conversion of MCh to a recipient cell type was found in leukemic relapse with a more than 90% host-derived erythroid and megakaryocytic cell population in 4 patients approximately 643 days after BMT.

Adult↗

Analysis of the mouse transcriptome based on functional annotation of 60,770 full-length cDNAs.

Only a small proportion of the mouse genome is transcribed into mature messenger RNA transcripts. There is an international collaborative effort to identify all full-length mRNA transcripts from the mouse, and to ensure that each is represented in a physical collection of clones. Here we report the manual annotation of 60,770 full-length mouse complementary DNA sequences. These are clustered into 33,409 'transcriptional units', contributing 90.1% of a newly established mouse transcriptome database. Of these transcriptional units, 4,258 are new protein-coding and 11,665 are new non-coding messages, indicating that non-coding RNA is a major component of the transcriptome. 41% of all transcriptional units showed evidence of alternative splicing. In protein-coding transcripts, 79% of splice variations altered the protein product. Whole-transcriptome analyses resulted in the identification of 2,431 sense-antisense pairs. The present work, completely supported by physical clones, provides the most comprehensive survey of a mammalian transcriptome so far, and is a valuable resource for functional genomics.

Alternative Splicing↗

Totally extraperitoneal endoscopic inguinal hernia repair (TEP).

BACKGROUND: This report reviews our experience with 5,203 totally extraperitoneal (TEP) endoscopic hernia repairs performed in 3,868 patients over the 7.5-year period between May 1994 and December 2001, 34.5% of whom had bilateral hernias and 13% recurrent hernias. METHODS: We performed TEP as the method of choice in more than 92% of all the patients presenting with inguinal hernia, including those with incarcerated, strangulated, or inguinoscrotal hernias. After reduction of the hernial sac and appropriate dissection of the preperitoneal space, we placed a slit-free 10 x 15-cm polypropylene mesh without the use of staple fixation. RESULTS: Altogether, 29 recurrent hernias (0.6%) were observed, more than 50% of which occurred during the first 2 years after the technique was introduced (1.8%). During subsequent years, the recurrence rate settled to approximately 0.3%. Regarding intraoperative complications, we observed eight injuries to the bladder. At this writing, no bowel injuries or damage to iliac vessels has been seen. Postoperatively, we noted only a single case of mesh infection. In 14 cases (0.4%), postoperative hemorrhage necessitated either inguinal or endoscopic reoperation. As a further major complication, a small bowel obstruction caused by inadequate closure of a peritoneal lesion occurred in two patients (0.05%). The overall reoperation rate for the 3,868 patients was 0.6%. CONCLUSIONS: We consider TEP to be a procedure that carries an acceptably low complication rate, combining the advantages of minor access surgery and mesh reinforcement of the groin. This approach is associated with early postoperative return to usual activities and a very low recurrence rate.

Adolescent↗

Computer-enhanced robotic telesurgery. Initial experience in foregut surgery.

BACKGROUND: A new type of computer-enhanced telemanipulator device for "robotic" laparoscopic surgery was recently approved. We prospectively evaluated the initial patients undergoing procedures with this new device at our institution. METHODS: Patient demographics, operative indications, port placement, operative time, robot time, complications, and hospital stay were recorded. Follow-up evaluation was appropriate for the individual procedure. RESULTS: Initially, 35 cases were managed. There were 22 anti-reflux procedures, 9 Heller myotomies, 1 pyloroplasty, 1 distal pancreatectomy with splenectomy, 1 esophagectomy with intrathoracic anastomosis, and 1 diagnostic laparoscopy. The operative times ranged from 88 to 458 min. The robot use times were between 16 and 185 min. There were no device-related complications. CONCLUSIONS: Computer-enhanced robotic telesurgery is a safe and effective treatment method for a variety of diseases of the proximal gastrointestinal tract. Further study is needed to determine the benefits of this approach as compared with current technology.

Anastomosis, Surgical↗

Laparoscopic treatment of rectal prolapse: experience gained in a prospective multicenter study.

BACKGROUND: We report the findings of a prospective multicenter observational study carried out by the Study Group for Laparoscopic Colorectal Surgery on patients undergoing laparoscopic or laparoscopic-assisted surgery for rectal prolapse. The study investigated the safety of various laparoscopic techniques in terms of perioperative and postoperative general and technique-specific complications and compared the results with those reported for open surgery in this area. METHODS: Of the 150 patients undergoing laparoscopic or laparoscopic-assisted colorectal surgery for rectal prolapse 124 received rectopexy combined with resection and 26 rectopexy alone. In 85 patients a mesh was employed during rectopexy. The conversion rate was 5.3%. RESULTS: Perioperative complications (21 surgical and 35 general perioperative) were recorded in 37 patients (24.7%). The reoperation rate was 5.3% (bleeding 2, anastomotic leak 2, ileus 4). No procedure-specific perioperative complications were observed. In particular, reduced surgical trauma led to fewer severe postoperative complications such as cardiopulmonary problems (3.3%). CONCLUSIONS: The techniques of conventional prolapse surgery can readily be translated to the laparoscopic modality, since oncological criteria do not have to be considered. The usually elderly patients in this group benefit to a particular degree from the known advantages associated with reduced surgical trauma. Perioperative morbidity is determined largely by the surgeon's experience. We therefore believe that rectal prolapse is a suitable indication for the minimally invasive modality in the hands of trained surgeons.

Aged↗

Mycophenolate mofetil in the therapy of polymyositis associated with a polyautoimmune syndrome.

Mycophenolate mofetil 1.5 g daily (30 mg/kg body weight) was given to a patient with ankylosing spondylitis, ulcerative colitis, and severe refractory polymyositis after conventional treatment regimes had failed. No severe side effects occurred. Considerable improvement of clinical symptoms and electromyographic findings were seen within 6 months after the initiation of mycophenolate mofetil, allowing for tapering and discontinuation of methylprednisolone. Mycophenolate mofetil may be considered as an useful alternative in the treatment of polymyositis when standard therapeutic regimens fail.

Anti-Inflammatory Agents↗

Laparoscopic sigmoid resection for cancer: curative resection and preliminary medium-term results.

PURPOSE: Despite reservations about compliance with oncologic radical criteria, laparoscopic resection of the sigmoid colon is increasingly being used with curative intent in oncologic surgery of the colorectum. The aim of the present study was to obtain further information on the perioperative course, the oncologic radicalness of the procedure, and medium-term outcome. METHODS: The data presented here were obtained from a prospective, multicenter study conducted in Germany and Austria. These data were acquired from an analysis of subgroups derived from a total of 3,133 recruited patients. RESULTS: A total of 292 patients from 36 hospitals underwent laparoscopic resection of the sigmoid colon with curative intent. The definitive histopathologic work-up of surgical specimens revealed the following International Union Against Cancer tumor stages: 122 Stage I, 86 Stage II, and 84 Stage III. The mean operating time was 172 minutes, and the mean intraoperative blood loss was 241 ml. The conversion rate to open surgery was 5.5 percent, the majority of such conversions being made necessary by vascular lesions. Sixty-five of the patients reported at least one postoperative problem or complication (22.3 percent); the mortality rate was 2.7 percent. With a mean of 13.4 recovered lymph nodes and a mean aboral safety margin of 72 mm, the formal criteria for the assessment of oncologic radicalness were met. Intraoperative cell dissemination occurred in two patients. The long-term results, which, at a mean follow-up of 2.1 years and a follow-up rate of 73.3 percent, must be considered preliminary, show a calculated stage-related survival rate of 88.8, 90.9, and 64.1 percent, respectively, for the International Union Against Cancer Stages I, II, and III. CONCLUSIONS: Laparoscopic sigmoid resection can be performed technically reliably-also with curative intent-with acceptable complication and mortality rates and, to date, with survival rates that are at least comparable with those achieved with open surgical procedures.

Adult↗

Intolerance to neuroleptics and susceptibility for malignant hyperthermia in a patient with proximal myotonic myopathy (PROMM) and schizophrenia.

We report a patient with proximal myotonic myopathy who was treated with neuroleptics because of exacerbating schizophrenia. Under therapy with fluanxol, the patient developed muscle stiffness and oculogyric cramps. Treatment with both amisulpride and olanzapine lead to markedly elevated serum creatine kinase levels. An in-vitro contracture test was positive for halothane. Thus, in patients with all kinds of multisystemic myotonic myopathies, a susceptibility for malignant hyperthermia and intolerance towards neuroleptics should be taken into account.

Adult↗