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Biomedical subjects

R Bittner

Publications and source records attributed to R Bittner.

At least 55 records · Page 3Linked to original sources
PubMed1999

Fine structural analysis of extraocular muscle spindles of a two-year-old human infant.

PURPOSE: To clarify whether structural peculiarities formerly described in extraocular muscle (EOM) spindles of aged persons are already present in EOM spindles of a 2-year-old infant. METHODS: Distal halves of two EOMs obtained from a 2-year-old multiorgan donor were immersion-fixed and prepared for electron microscopy. The fine structure of 10 muscle spindles and of 1 "false spindle" was investigated. RESULTS: Extraocular muscle spindles of an infant 2 years of age had 2- to 4-layered outer capsules, 376 microm (range, 217-606 microm) long and 97 microm (range, 55-140 microm) wide. In 10 EOM spindles, 4 to 16 intrafusal muscle fibers (mean, 7.9) were present. From a total of 79 intrafusal fibers, 43 (54%) were nuclear chain fibers, and 8 of the 43 exhibited posttraumatic degenerative changes. Thirty-six (46%) intrafusal fibers indistinguishable from extrafusal fibers were called anomalous fibers. No nuclear bag fibers were found. Each muscle spindle contained a variable number of chain fibers and at least one anomalous fiber. Sensory nerve terminals were restricted to the 35 normal chain fibers but were absent from damaged chain fibers and from anomalous fibers. One "false spindle" without a periaxial space was composed of three anomalous fibers and one chain fiber, all of them devoid of sensory terminals. CONCLUSIONS: Most structural particularities of human EOM spindles described in aged persons are already found in the infant. They cannot be interpreted as age-related changes, but rather they represent specific features of human EOM spindles.

Aged↗
PubMed1998

Increased sensitivity to rocuronium and atracurium in mitochondrial myopathy.

PURPOSE: To describe the prolonged effect of the intermediate-acting, non-depolarising neuromuscular blocking agents rocuronium and atracurium in a 29-yr-old apparently healthy woman. CLINICAL FEATURES: Because of abdominal pain the patient was scheduled for explorative laparoscopic pelvic examination. General anaesthesia was induced with fentanyl, midazolam and propofol. Muscle relaxation was achieved with 0.6 mg.kg-1 rocuronium. Anaesthesia was maintained with nitrous oxide and propofol. Two Hz train-of-four stimulation every 15 sec evoked no twitch responses until 60 min after rocuronium. Further relaxation was achieved with 0.075 mg.kg-1 atracurium after which twitch responses recurred after 45 min. Fifteen minutes later neuromuscular blockade was successfully reversed with atropine and neostigmine. The postanaesthetic course was uneventful. Because of the increased sensitivity to rocuronium and atracurium the patient was re-evaluated postoperatively. History revealed occasional double vision, fatigue, muscle cramps, stiffness and myoglobinuria. Clinical neurological examination showed ptosis, tremor, ataxia and bradydiadochokinesia. A standardised lactate stress testing on a bicycle was pathological and, after muscle biopsy, the diagnosis of mitochondrial myopathy was established. CONCLUSION: An increased sensitivity to rocuronium and atracurium may occur in patients with mitochondrial myopathy. In these patients appropriate dosing of muscle relaxants and adequate monitoring of the neuromuscular blockade are required. If an increased sensitivity to rocuronium and atracurium occurs in an apparently healthy subject, further neurological investigations should follow.

Adult↗
PubMed1998

[Risks and benefits of laparoscopic hernia-plasty (TAPP). 5 years experiences with 3,400 hernia repairs].

In the present study, for the first time the aspects of risk, benefit and the costs of laparoscopic hernioplasty in the transabdominal technique with preperitoneal placement of a polypropylene mesh are examined prospectively in a very large group of patients with 3,400 hernia repairs. The median operation time was 45 min for unilateral primary hernias, 50 min for unilateral recurrent hernias and 76 min for bilateral hernias. The frequency of complications showed a significant dependence on the individual steps in the development of the method and the individual learning curve. The same is true for the rate of recurrency. Whereas initially the rate of serious complications was 2.75%, the rate of minor complications 11% and the rate of recurrences 4.5% the corresponding figures are at present 0.4%, 4.4% and 0.5%. Laparoscopic hernioplasty proved to be equally as effective in the treatment of primary hernias, recurrent hernias and bilateral hernias. The large number of 11 surgeons participating proves that laparoscopic hernioplasty can be learned and that even in a teaching hospital it can be performed safely, efficiently and cost-effectively.

Adolescent↗
PubMed1998

A single institution's experience with transperitoneal laparoscopic hernia repair.

BACKGROUND: Previous evaluations of endoscopic hernia surgery mostly are based on small prospectively documented series or on a few randomized comparative studies. In the following, results of a large single-institution experience concerning the transabdominal preperitoneal patch (TAPP) technique with regard to the development of methods and the routine use are described. METHODS: From April 1993 to March 1997, 2,700 TAPP procedures were performed at the Department of General and Visceral Surgery, Marien-hospital, Stuttgart, Germany. The follow-up was documented prospectively in all cases by use of computed data base. RESULTS: The majority of patients (83.8%) were operated because of primary hernias. In 17.2% a first or multiple recurrence of an inguinal hernia was indicated. At a median postoperative observation period of presently 20 months and a follow-up rate of 86.5%, 28 recurrences have been determined so far (total recurrence rate 1.03%), 6 of which occurred after a recurrent hernia reparation (1.33%) and 22 after primary hernia repair (0.97%). The most common cause for recurrence was in 39.3% a mesh (12 x 8 cm) being too small. The total complication rate was 4.6%; as an expression of the learning curve it was reduced from 7.8% (operations 1 to 500) to 2.8% (operations 2,200 to 2,700). CONCLUSIONS: According to our experience, the TAPP technique is sufficiently applicable as a standard method for an unselected group of patients in a routine setting. It is especially suited to the repair of recurrent and bilateral hernias as well as for patients with a high risk for recurrence that can profit from a tension-free endoscopic procedure, particularly in case of obesity.

Female↗
PubMed1998

Update: what is left for laparoscopic hernia repair?

The risks, benefits and costs of laparoscopic hernia repair are still being debated. According to a current survey on the situation of hernia surgery in Germany in 1996, laparoscopic hernioplasty was done in about 60% of the answering hospitals; about a quarter of all hernia repairs are done laparoscopically. Since April 1993, about 2, 700 laparoscopic hernia repairs were done at Marienhospital Stuttgart. The operating time was on the average 50 min. The rate of complications was about 3%. The postoperative period of disablement was a median of 20 days; included in this time was the postoperative hospital stay. The recurrence rate was about 1%. It is remarkable that laparoscopic hernia repair was equally efficient in repairing unilateral primary hernias, recurrent hernias or bilateral hernias. The cost analysis showed that the application of multipath articles will make the operation costs of laparoscopic hernia repair only about DM 100 higher than for a conventional operation.

Costs and Cost Analysis↗
PubMed1998

[Biliary pancreatitis--epidemiology, progress with a new therapy concept?].

In our patients with symptomatic cholelithiasis (n = 3618 in a 6-year period), we found biliary pancreatitis in 4.4% (0.4% severe pancreatitis). Because of therapeutic splitting (ERC/EPT, followed by laparoscopic cholecystectomy), we are able to reduce the hospital stay by about 60%, reduce morbidity significantly (P < 0.05) and reduce lethality.

Adult↗
PubMed1997

Targeted inactivation of plectin reveals essential function in maintaining the integrity of skin, muscle, and heart cytoarchitecture.

Previous studies suggest that plectin, a versatile cytoskeletal linker protein, has an important role in maintaining the structural integrity of diverse cells and tissues. To establish plectin's function in a living organism, we have disrupted its gene in mice. Plectin (-/-) mice died 2-3 days after birth exhibiting skin blistering caused by degeneration of keratinocytes. Ultrastructurally, hemidesmosomes and desmosomes appeared unaffected. In plectin-deficient mice, however, hemidesmosomes were found to be significantly reduced in number and apparently their mechanical stability was altered. The skin phenotype of these mice was similar to that of patients suffering from epidermolysis bullosa simplex (EBS)-MD, a hereditary skin blistering disease with muscular dystrophy, caused by defects in the plectin gene. In addition, plectin (-/-) mice revealed abnormalities reminiscent of minicore myopathies in skeletal muscle and disintegration of intercalated discs in heart. Our results clearly demonstrate a general role of plectin in the reinforcement of mechanically stressed cells. Plectin (-/-) mice will provide a useful tool for the study of EBS-MD, and possibly other types of plectin-related myopathies involving skeletal and cardiac muscle, in an organism amenable to genetic manipulation.

Animals↗
PubMed1997

Muscle transformation of the sartorius muscle in a canine model: clinical impact for electrodynamic graciloplasty as a "neosphincter".

PURPOSE: Transformation of fast-twitching skeletal muscles to slow-twitching, slowly fatigable muscles has become of clinical interest in the recent past. Transposition and transformation of the gracilis muscle to use it as a substitute for a resected or defected anal sphincter (graciloplasty) have been reported as achieving promising results in the treatment of fecal incontinence caused by sphincter defects or following abdominoperineal anorectal excision for cancer. METHOD: This experimental study used a canine model and the sartorius muscle to evaluate the functional efficiency of two different configurations of the muscle loop to compare the presently applied transformation program (8 weeks) with a shorter (5 weeks) protocol. In six beagle dogs, both sartorius muscles were wrapped around two stomas, either in an alpha fashion or in the so-called split-sling technique. Muscle transformation was achieved by controlled neuromuscular stimulation either during eight (Program A) or five weeks (Program B). After completion of the transformation period, the function of the muscle slings was evaluated by manometry, and histomorphologic evaluation of the sartorius muscles was performed. RESULTS: It was shown that muscle transformation led to a slowly fatigable muscle that made it possible to perform continuos (tetanic) contraction, regardless of the configuration or the duration of the transformation. Median pressures created by these muscles also did not differ significantly. In accordance with these functional findings, the histologic evaluation showed the typical, significant increase of Type I fibers in both muscle slings and following both transformation protocols. Although the decrease of fast-twitching Type II fibers was more pronounced following the conventional (8 weeks) program, this finding did not influence the functional results. CONCLUSIONS: Results of our experiment indicate the possibility for using a shorter transformation protocol for transformation of the gracilis muscle during graciloplasty in the clinical setting. Furthermore, the efficacy and safety of the modified (split-sling) wrap technique was demonstrated.

Anal Canal↗
PubMed1997

[Laparoscopic cholecystectomy in therapy of acute cholecystitis: immediate versus interval operation].

From January 1991 to May 1996 a total of 3,010 cholecystectomies was performed for cholelithiasis. Pathohistologically an acute cholecystitis was found in 483 patients (16%). The overall proportion of laparoscopic operations has increased from 12.5% in 1991 to 96.6% at present. In patients with acute cholecystitis the proportion of laparoscopic operations has increased from initially only 1.87% up to 83.3%. The duration of surgery (81 min versus 54 min), rate of conversion (12% versus 1.07%) and rate of complications (7.76% versus 2.2%) were all significantly higher in cases of acute cholecystitis than in those without inflammation. There was no mortality in either group. Furthermore no significant difference was found between patients with histopathologically proven acute inflammation and patients with an acute episode of chronic cholecystitis. The duration of complaints, however, had a significant influence on surgical results. In patients that were either operated on within 48 h after the onset of disease or more than 10 days later, the length of the operation was shorter and the rates of conversion and complications were lower. Our results prove that laparoscopic cholecystectomy is also very successful in cases of acute cholecystitis, though a long learning curve has to be expected. Taking efficiency and economy into consideration, surgery within a few days of the onset of disease must be recommended.

Acute Disease↗
PubMed1997

Spatial distribution of beta-spectrin in normal and dystrophic human skeletal muscle.

Spectrin, a major component of the erythrocyte membrane skeleton, has previously been shown to form a two-dimensional lattice in erythrocytes, and in avian or chicken skeletal muscle. Those results were mainly obtained with antibodies against alpha-spectrin. Using immunofluorescence of semithin cryosections and single muscle fiber preparations, we show here that beta-spectrin forms a costameric network which covers the plasma membrane of human skeletal muscle. These spectrin costameres are correlated with the Z-bands. They are longitudinally connected by fine strands and interrupted by myonuclear lacunae. Under mechanical stretching, the costameres retained their correlation to the Z-bands in normal and dystrophin-deficient muscle, up to the point at which the sarcolemma was disrupted. In stretched muscle, in some regions of the stretched fibers in which the costameres seemed to form double strands, the usually 1:1 correlation of spectrin to the Z-bands changed to a 2:1 relation. In dystrophin-deficient muscle, the costameric scaffold of spectrin in the well-preserved fibers appeared normal, indicating that spectrin can be correctly localized in the absence of dystrophin and that the subcellular spectrin organization does not primarily depend on dystrophin expression. The regular organization and the correlation of spectrin costameres to the Z-bands was notable even in stretched Duchenne muscular dystrophy (DMD) muscle. On the other hand, single teased muscle fibers of DMD muscle showed various degrees of morphological alterations of the costameric network, ranging from a focal disarray to complete loss of costameric organization. Because these findings indicate that the costameric spectrin scaffold undergoes secondary changes during the course of the dystrophic process in dystrophin-deficient muscle, spectrin staining of isolated muscle fibers may also serve as a tool to monitor the effect of gene therapy experiments at the single fiber level.

Blotting, Western↗
PubMed1997

[Laparoscopic hernia repair: prevention and therapy of complications].

Following the surgical steps in laparoscopic (transperitoneal) hernia repair, the corresponding groups of complications relate to: (1) laparoscopy; (2) the trocars; (3) the dissection of the inguinal region; (4) the hernia sac dissection; (5) the mesh placement; (6) the peritoneal closure. Inadequate surgical technique can lead to injuries of the intestine, urinary bladder and blood vessels; peri- and postoperative bleeding and hematoma; severing of testicular blood vessels, with consecutive testicular atrophy; and nerve lesions when fixing the mesh with clips and intestinal obstruction subsequent to insufficient peritoneal closure. With an adequate surgical technique, complication rate is very low. Preconditions for this are: strict compliance with the safety tests, when establishing the pneumoperitoneum; application of blunt conical trocars; precise knowledge of the anatomy; gentle dissection in the avascular tissue layers; subtle hemostasis; absolutely no diffuse electrocoagulation or placement of any clips below or up to 1 cm above the ileopubic tract; and safe peritoneal closure by suture under reduced intraabdominal pressure.

Hernia, Inguinal↗
PubMed1996

[Endoscopic hernia surgery (TAPP)--gold standard in management of recurrent hernias?].

From April 1993 to December 1995 210 TAPP procedures were performed because of recurrent hernia. With the TAPP method there is no difference between primary and recurrent repair. All procedures in this study were done with general anaesthesia by senior surgeons. The learning curve shows a reduction of operation time (60 to 55 min) with increasing experience and a reduction in complications as well (total 4.3%). Recurrence was observed in two cases. The reasons for these recurrences were technical failures during the previous repair. In both cases a second TAPP repair was carried out successfully. The main advantage of TAPP in recurrent hernia is that this method gives possibilities to avoid anterior scar tissue. Secondly tension-free repair can be combined with the benefit of the minimal access technique. For this reason, the TAPP procedure must be considered the method of choice in recurrent hernia repair.

Adult↗
PubMed1996

Studies on nutritional status in general surgery patients by clinical, anthropometric, and laboratory parameters.

We assessed the nutritional status of general surgery patients with and without cancer from a western European population in this prospective study. Anamnestic (weight development, abdominal complaints) and anthropometric (fat tissue measurements) data were collected on six groups of patients: cancer of the stomach (n = 13), pancreas (n = 13), colorectal (n = 23), breast (n = 12), and two control groups with benign diseases, ages 20-45 and 50-75 y. From these data, body mass index and ideal body weight were calculated. Concentrations of albumin, transferrin, retinol-binding protein, prealbumin, and creatinine height index were determined by biochemical tests. A weight loss of more than 10% was found in only 31% of gastric and 61% of pancreatic cancer patients. Significant values from anthropometric data were also found only in these groups. In biochemical tests, only the creatinine height index was reduced in all patients with pancreatic cancer. The remaining laboratory changes were so unspecific in all other parameters that no conclusions could be drawn as to the status of the patient's nutritional condition. For the evaluation of nutritional status, only relatively simple and inexpensive anamnestic and anthropometric measurements are necessary.

Adult↗
PubMed1996

Total gastrectomy. Updated operative mortality and long-term survival with particular reference to patients older than 70 years of age.

OBJECTIVE: The authors conducted a study of patients who underwent total gastrectomy for gastric malignancy to elucidate contributing factors that lead to successful management of this disease in geriatric patients. SUMMARY BACKGROUND DATA: The average mortality rate for patients undergoing stomach surgery due to carcinoma is 7.8% according to the literature overview, still relatively high. Even higher mortality rates are observed for geriatric patients after a total gastrectomy. Because of epidemiologic changes, a total gastrectomy is required with growing frequency in these high-risk patients. METHODS: The study involved 380 patients with a gastric malignancy. Risks and benefits of a total gastrectomy with radical lymphadenectomy at an advanced age were analyzed retrospectively in 163 patients older than 70 years of age. The results achieved in these patients were compared with those observed in 217 younger patients. RESULTS: The 30-day mortality and morbidity rates for the elderly patients were 3% and 33.7%, respectively; for the younger patients, they were 0.46% and 21.2%, respectively. A statistically significant correlation was found between the presence of risk factors, the occurrence of complications, and the mortality rate. No difference was seen between the two age groups when risk factors were absent. The 5-year survival rate was 30%, with no difference between young and elderly patients. CONCLUSIONS: The data prove that a total gastrectomy with a radical lymphadenectomy can be carried out safely in older patients, with long-term results comparable to those achieved in younger patients.

Age Distribution↗
PubMed1996

Evidence for compound heterozygosity causing mild and severe forms of autosomal recessive spinal muscular atrophy.

Spinal muscular atrophy is an autosomal recessive disease of motor neurone degeneration which shows a variable phenotype. Two candidate genes show deletions in affected subjects but with no distinction between different forms of the disease. We report an unusual family in which mild and severe SMA coexists and patients are deleted for the SMN gene. The father is affected with late onset SMA; therefore this family shows pseudodominant inheritance. When typed using closely linked flanking markers the severely affected son does not share the same haplotype as his sib, who is deleted for SMN but shows no signs yet of SMA. This supports the hypothesis that differences in SMA phenotype can be explained by a multiple allele model.

Adult↗