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Biomedical subjects

A Koch

Publications and source records attributed to A Koch.

At least 181 records · Page 10Linked to original sources
PubMed1998

[Current status of treatment of appendicitis. Results of 2 prospective multicenter studies in East Germany. East German Working Group "Outcome Assessment and Quality Assurance in Surgery" of the CAQ of the German Society of Surgery].

In a period of 10 years we carried out two prospective multicentric trials to evaluate the state of the art in treatment of appendicitis. One study was performed before introduction of laparoscopy. Important criteria like new diagnostic methods (sonography, laparoscopy), frequency of operation, perforation rate, frequency of appendectomies in case of non acute inflammation and postoperative complications were compared.

Appendectomy↗
PubMed1998

[Diagnostic laparoscopy within the scope of appendicitis treatment. East German Working Group "Outcome Assessment and Quality Assurance in Surgery" of the CAQ of the German Society of Surgery].

The diagnostic laparoscopy represents a special technique with high impact for differential diagnosis especially in patients with chronic recurrent pain in the right lower abdomen. The East-German multicentric trial confirmed the actual trend of increasing importance of the laparoscopic method especially in patients with unclear abdominal findings. In case of surgical treatment because of chronic appendicitis in 61.7% (n = 370) of all these cases an laparoscopic procedure was preferred. Unclear abdominal findings were treated in 73.7% (n = 205) laparoscopically. In case of acute appendicitis in 72.2% (n = 2934) the open procedure was preferred. The diagnostic laparoscopy can avoid the overlook of findings requiring therapy. The consequent laparoscopic approach allows to achieve a decreased rate of non necessary laparotomies as well as non detected findings requiring surgery. The rate of gynaecological findings was 16.2% (n = 184) of all women who underwent diagnostic laparoscopy versus 6.4% who underwent open appendectomy (n = 116).

Adolescent↗
PubMed1998

[Incidence of bacterial pneumonia in HIV-positive patients treated with preventive co-trimoxazole or pentamidine].

BACKGROUND: Besides Pneumocystis carinii bacterial pathogens represent the most common aetiology of pulmonary infections in HIV-positive patients. However, the impact of PCP prophylaxis on the incidence of bacterial pneumonia in HIV-positive patients using pentamidine or co-trimoxazole is still unknown. PATIENTS AND METHODS: We analysed retrospectively the data of 80 consecutive HIV-positive patients with a CD4-cell count < 300/microliter. The total observation period was 1993 patient months. Type and duration of chemoprophylaxis, frequency of bacterial pneumonia, PCP, extrapulmonary bacterial infections and cerebral toxoplasmosis were documented in a standardised manner. For statistical analysis we used the Kaplan-Meier test for the time to a recurrence of the various infections under both prophylaxis regimens and the Odds ratio for determination of the relative risk. RESULTS: We followed up 47 patients inhaling 300 mg pentamidine monthly for a total of 1133 months and 33 patients taking 480 mg co-trimoxazole per day p.o. for a total of 860 months. There were no statistically significant differences between the two groups in respect of demographic parameters, stage and therapy of HIV infection and distribution of risk groups. We found seven bacterial pneumonias in the co-trimoxazole group and 13 in the pentamidine group (not significant); the most common causative organisms were S. pneumoniae (n = 4), S. aureus (n = 3) and H. influenzae (n = 3). Furthermore, in the pentamidine group 12 PCP and nine cases of toxoplasma encephalitis were observed, whereas none of these infections occurred in the co-trimoxazole group (p < 0.05). Two of the patients taking co-trimoxazole and 15 of those inhaling pentamidine had extrapulmonary bacterial infections (p < 0.05), the most frequently identified pathogen being S. aureus (n = 7). The two prophylaxis groups did not differ significantly with regard to laboratory data, course and therapy of the bacterial pneumonias. CONCLUSION: There was no significant influence of chemoprophylaxis on the incidence of bacterial pneumonia in patients with advanced HIV-disease in our study. Since S. pneumoniae represents the most common causative agent, we suggest immunisation with a polyvalent pneumococcal vaccine at an early stage of HIV-infection.

AIDS-Related Opportunistic Infections↗
PubMed1997

HPV detection in children prior to sexual debut.

Knowledge of the epidemiology of infection with human papillomavirus (HPV) in childhood is important, since HPV infection early in life could represent a risk factor for later development of anogenital cancer. A random sample of Danish children aged 0 to 17 years was tested for the presence of HPV in the anal region and the oral cavity by the polymerase chain reaction using a consensus HPV L1 primer. Only 4 of 249 anal beta-globin-positive samples and one of 392 oral beta-globin-positive samples were HPV-positive. All HPV-positive samples were of unknown types. We conclude that the prevalence of anogenital HPV infection in childhood is very low indeed and that the oral cavity does not seem to act as a reservoir for HPV infection in childhood. This indicates that anogenital types of HPV are not transmitted to any measureable degree by non-sexual routes and further supports the notion that HPV infection takes place mainly later in life.

Adolescent↗
PubMed1997

Influence of the global utilization of streptokinase and tissue plasminogen activator for occluded coronary arteries (GUSTO-1) trial on the use of thrombolytics in Germany. ALKK Study Group. Arbeitsgemeinschaft der Leitenden Kardiologischen Krankenhausärtze.

Our results show significant and independent influence of the GUSTO-1 trial on the use of recombinant tissue plasminogen activator in acute myocardial infarction in Germany. This influence started soon after the publication of the trial and was not restricted to subgroups who benefitted most from recombinant tissue plasminogen activator.

Aged↗
PubMed1997

Identification of a second Grb2 binding site in the v-Fms tyrosine kinase.

Tyrosine autophosphorylation of the v-Fms oncogene product results in the formation of high-affinity binding sites for cellular proteins containing Src homology 2 (SH2) domains. These proteins transduce various mitogenic and morphogenic signals. As reported previously, Y696KNI in the kinase insert domain of v-Fms binds to the growth factor receptor bound protein 2 (Grb2), a stimulator of the Ras/Raf1 pathway. Here, we mapped Y921TNL within the C-terminal domain of Fms as a novel autophosphorylation site. We demonstrate that this site constitutes a second Grb2 binding site: a recombinant fusion protein (residues 904-944) containing phosphorylated Y921 bound Grb2 from FDCP-1Mac11 cell extracts significantly more efficiently than a corresponding protein (residues 617-759) containing Y696. A yeast two-hybrid system which allowed the formation of a functional Fms tyrosine kinase was employed to quantify binding of Grb2. Fms-protein containing either one of the two phosphorylation sites bound Grb2 equally well, binding was increased for proteins carrying both sites. In contrast, the simultaneous substitution of Y696 and Y921 by phenylalanines abolished Grb2 binding. Mouse NIH3T3 cells expressing the Y921F mutant Fms-protein showed a substantially higher content of fibronectin network than wild-type transformed cells and had largely lost their serum independent growth phenotype.

3T3 Cells↗
PubMed1997

Mycoplasma hominis and Ureaplasma urealyticum in patients with sexually transmitted diseases.

Mycoplasma hominis and Ureaplasma urealyticum can be isolated with considerable frequency from the human urogenital tract and are thought to cause various syndromes such as nongonococcal urethritis, pelvic inflammatory disease, pyelonephritis or infertility. The aim of this study was the evaluation of the presence of different genital pathogens in patients with sexually transmitted diseases (STD) and, in particular, the detection of mycoplasmas in individuals infected with genital microbes and an assessment of the presence of genital microorganisms in patients harbouring Mycoplasma hominis or Ureaplasma urealyticum. Furthermore, the occurrence of mycoplasmas in women with bacterial vaginosis was established. Specimens were collected from a total of 41,980 persons attending the Outpatients' Centre for Infectious Venero-Dermatological Diseases in Vienna from 1994 to 1996. Of all genital pathogens, Ureaplasma urealyticum was cultured most frequently in men and women. Mycoplasma hominis and Ureaplasma urealyticum were detected more often in the vaginal fluid than in the male urethra. By contrast, infection rates with Neisseria gonorrhoeae and Chlamydia trachomatis were higher in men than in women. In both men and women, trichomoniasis increased colonisation with Mycoplasma hominis, while mycoplasmas occurred less frequently together with genital candidiasis. Mycoplasma hominis was cultivated significantly more often in women with bacterial vaginosis than in those without. In contrast to urethral infections in men, cervical infections with Neisseria gonorrhoeae or Chlamydia trachomatis raised the incidence of Mycoplasma hominis in the vaginal fluid.

Adult↗
PubMed1997

Medulloblastomas of the desmoplastic variant carry mutations of the human homologue of Drosophila patched.

Inactivating mutations in the PTCH gene, a human homologue of the Drosophila segment polarity gene patched, have been identified recently in patients with nevoid basal cell carcinoma syndrome. These patients are predisposed to various neoplasias including basal cell carcinomas and medulloblastomas (MBs). To determine the involvement of PTCH in sporadic MBs, which represent the most frequent malignant brain tumors in children, we screened for PTCH alterations in an unselected panel of 64 biopsy samples from 62 patients and four continuous MB cell lines, all derived from patients with sporadic MBs. Using single-strand conformational polymorphism analysis, we screened exons 2-22 and detected nonconservative PTCH mutations in 3 of 11 samples from sporadic cases of the desmoplastic variant of MB but none in 57 MBs with classical (nondesmoplastic) histology. In two of the tumors with mutations and in two additional desmoplastic cases, loss of heterozygosity was found at 9q22. These findings suggest that PTCH represents a tumor suppressor gene involved in the development of the desmoplastic variant of MB.

Adolescent↗
PubMed1997

An optimized protocol for mRNA quantification using nested competitive RT-PCR.

Nested competitive reverse transcription polymerase chain reaction is an effective tool for the quantification of low level expressed mRNAs. Competitive RNA standards with small deletions allow the use cRT-PCR. The sensitivity is further increased by the utilization of nested PCR protocols. To optimize quantification of low abundance mRNAs we modified established protocols for use of automated labstations and semiautomated sequencers. In placental tissue, known for a very high CYP19 (P450AROM, aromatase) expression, cRT-PCR and nested cRT-PCR yielded virtually identical results which could be confirmed by Northern blotting. CYP19 mRNA in breast tumour tissue ranged below detection levels for Northern blotting; however, using our modified assay CYP19 showed 1.5 to 15 fold higher expression levels than in normal glandular breast tissue. Our approach proved to be useful for the quantification of a gene with low level expression. The employment of labstations and semiautomated sequencers allows rapid analysis of large sample numbers.

Aromatase↗
PubMed1997

Primary angioplasty versus thrombolysis in the treatment of acute myocardial infarction. ALKK Study Group.

This study investigates the hypothesis if primary angioplasty is superior to intravenous thrombolysis in the treatment of acute myocardial infarction (AMI). Small prospective randomized studies did not demonstrate a significant benefit regarding total mortality. A total of 14,980 patients with AMI were registered by "The 60-Minutes Myocardial Infarction Project," a prospective multicenter observational study: 210 of these patients were treated with primary angioplasty. A matched pair analysis comparing 1 primary angioplasty patient with 3 intravenous thrombolysis patients could be performed in 156 primary angioplasty patients. Criteria for matching were age, sex, location of AMI, systolic blood pressure, previous AMI, and prehospital delay. Patients with a bundle branch block or requiring resuscitation were excluded from analysis. Because of matching, both groups showed similar baseline characteristics. Patients with primary angioplasty had more relative contraindications for thrombolysis (ulcers: 10.3% vs 2.3%, recent intramuscular injections: 6.4% vs 1.6%, recent surgical interventions: 5.1% vs 1.1%, central punctures: 9% vs 3.9%). There was a tendency toward less combined adverse events in the primary angioplasty group (3.2% vs 5.7%, odds ratio [OR] = 0.55, 95% confidence interval [CI] = 0.21 to 1.44). In-hospital mortality rates in the primary angioplasty group and thrombolysis group were 4.3% and 10.3%, respectively (OR = 0.39, 95% CI = 0.17 to 0.92). The difference in mortality could already be demonstrated within the first 48 hours with 1.9% versus 5.3% deaths (OR = 0.35, 95% CI = 0.11 to 1.14). Thus this study indicates a superiority of primary angioplasty in comparison to intravenous thrombolysis in AMI even in a clinical routine setting, with a reduction of hospital mortality of about 60%.

Aged↗
PubMed1997

Symptoms in chronic constipation.

OBJECTIVES: This study was designed to evaluate whether detailed symptom analysis would help to identify pathophysiologic subgroups in chronic constipation. METHODS: In 190 patients with chronic constipation (age, 53 (range, 18-88) years; 85 percent of whom were women), symptom evaluation, transit time measurement (radiopaque markers), and functional rectoanal evaluation (proctoscopy, anorectal manometry, defecography) were performed. Patients were classified on the basis of objective data from all tests in four different groups ("disordered defecation," "slow gastrointestinal transit," "disordered defecation combined with slow-transit stool," and "no pathologic finding"). RESULTS: In 59 percent of patients, disordered defecation was found, and 27 percent had slow-transit stool. In 6 percent of patients, a combination of both was found; in only 8 percent of patients, there were no pathologic findings. Straining was reported by the vast majority in all groups (82-94 percent). Infrequent bowel movements and abdominal bloating were more common in slow-transit stool (87 and 82 percent vs. 69 and 55 percent, respectively; both P < 0.01). Feeling of incomplete evacuation was more common in disordered defecation (84 vs. 46 percent; P < 0.0001). However, specificity of these symptoms was discouraging (for slow-transit stool: infrequent bowel movements had a sensitivity of 87 percent and a specificity of 32 percent and abdominal bloating had a sensitivity of 82 percent and specificity of 45 percent; for disordered defecation: feeling of incomplete evacuation had a sensitivity of 84 percent and a specificity of 54 percent). Only the sense of obstruction and digital maneuvers were acceptably specific (79 and 85 percent, respectively) for disordered defecation, but sensitivity was low. CONCLUSIONS: Definition of chronic constipation by infrequent bowel movements alone is of little value; the symptom "necessity to strain" is much better suited (94 percent sensitivity). Specificity of infrequent bowel movements for slow-transit stool was discouraging. Sense of obstruction and digital manipulation for evacuation are relatively specific for disordered defecation but insensitive. Therefore, symptoms of chronically constipated patients are not well suited to differentiate between the pathophysiologic subgroups suffering chronic constipation.

Adolescent↗
PubMed1997

[Neurogenic temporomandibular joint dislocation. Definition and therapy with botulinum toxin].

Dislocation of the temporomandibular joint results from trauma, articulation disorders and changes in the equilibrium of the masticatory muscles. Previous classifications were mostly oriented on the interrelationships between the anatomical positions of the dislocated articular surfaces, like luxation, subluxation and discuss luxation. Etiologically, a distinction is made between traumatic and non-traumatic dislocation. Dislocation of the temporomandibular joint is described as a complication of a number of neurological diseases. We report on a patient who suffered recurrent dislocations of the temporomandibular joint as a complication of multiple sclerosis and whose luxations were successfully treated with botulinum toxin, thus warranting the introduction of the term "neurogenic dislocation of the temporomandibular joint".

Botulinum Toxins↗
PubMed1997

[Early treatment of acute myocardial infarct: implementation of therapy guidelines in routine clinical practice, MITRA pilot phase].

The prognostic value of thrombolytics, aspirin, beta-blockers and ACE-inhibitors has been well documented in large clinical trials, but the application of these drugs in clinical practice is not known. MITRA is a multicenter study of 54 hospitals in a defined region in southwest Germany. The aim is to document actual clinical practice (pilot phase) and to establish an individually optimised prognostic therapy for acute myocardial infarction, considering only the absolute contraindications for each drug. In the pilot phase, 1303 consecutive patients with acute transmural myocardial infarction were enrolled. The median age was 66 years, the prehospital time was 2.7 hours. 47% had an anterior infarction. In the subgroup of patients without absolute contraindications, only 53.4% were treated with thrombolytics, 87.6% with aspirin, 37.1% with beta-blocker, and 17.4% with ACE-inhibitor. Out of these, patients were classified as "optimally treated" if they received thrombolysis, aspirin as well as beta-blocker. Patients were also included if any of these medications was withheld in the presence of absolute contraindications. Treatment was defined suboptimal, if the patients did not receive any of these three medications despite the absence of absolute contraindications. Only 29% (n = 383) received an optimal post-infarction therapy and 71% (n = 775) a suboptimal treatment. The univariate analysis revealed 10 variables influencing optimal therapy. In this subgroup patients were younger, they more often had clear ECG-findings or left bundle branch block, an anterior infarction, acute cardiac failure, AV-block, bradycardia, recent trauma or surgery (less then 2 weeks) and a severe chronic obstructive lung disease. The prehospital time was more often available. Early mortality after 2 days was 5.0% versus 9.3% in the suboptimal treated patients (OR: 0.5, CI: 0.30-0.86) the total inhospital mortality was 10.9% in the optimal versus 17.7% in the suboptimal group (OR: 0.6, CI: 0.38-0.84). In a multivariate analysis the parameter "optimal treatment" was found to be an independent predictor of the early (OR = 0.4; CI: 0.20-0.69) and the inhospital mortality (OR = 0.4; CI: 0.25-0.64). The following in-hospital events occurred: stroke 2.8%, reinfarction 12.9%, cardiac failure 21.5%, cardiogenic shock 10.4% and in-hospital mortality 18.1% (2-days mortality 9.5%). Pharmacological therapy for acute myocardial infarction is inconsistent with the recommendations suggested in recent clinical trials and needs to be individually optimised. Optimal treatment is an independent predictor of early and inhospital mortality.

Adrenergic beta-Antagonists↗
PubMed1997

[Intrapericardial hemorrhage as a manifestation of mycoplasma pneumoniae infection].

Although carditis associated with Mycoplasma pneumoniae is infrequent it is an important cause of death in M. pneumoniae infections. We report on a 4-year-old boy with a M. pneumoniae infection, who developed a large hemorrhagic pericardial effusion and was successfully treated by percutaneous catheter drainage. Except in cancer patients, nontraumatic hemorrhagic pericardial effusions are rare. Our case strongly supports direct bacterial invasion into pericardial tissue as a cause of M. pneumoniae pericarditis rather than autoimmune phenomenon.

Child, Preschool↗
PubMed1997

Clinical and laboratory evaluation of a new thin-walled self-expanding tracheobronchial silicone stent: progress and pitfalls.

BACKGROUND: Although widely established in the management of malignant airway lesions, currently available tracheobronchial prostheses made of silicone have their drawbacks resulting from rigidity and wall thickness. Therefore we present clinical follow-up data obtained with a novel thin-walled expandable prototype silicone airway stent (Polyflex stent, Willy Rüsch AG, Kernen, Germany) in 19 patients. METHODS: Seventeen of 19 patients had tracheobronchial complications of infiltrating cancer: five had respiratory-digestive fistulas, 14 had mixed-type obstructions (mucosal infiltration plus extrinsic compression), and two had diffuse tracheal hemorrhages from the tumor surface (three patients had more than one complication). Two of 19 patients had benign postintubation stricture and malacia. Overall, 33 stents were implanted either simultaneously or in a consecutive manner. Scanning electron microscopy was performed both on prototype stents and on other available silicone stents for comparison. RESULTS: The treatment improved the patients' clinical condition substantially. The mechanical properties of the new prosthesis were excellent. Important stent-associated side effects were early mucus retention (n = 7), infolding of the inner silicone layer (n = 2), and stent dislodgment (n = 2). As of February 1997, 10 patients have died of causes unrelated to stent placement. Seven patients with malignant airway disease are still alive from 2 weeks up to 7 months after initial treatment. Scanning electron microscopy of explanted and unused prototypes suggested that an extremely ragged luminal microstructure may contribute to the firm adhesion of secretory material and that technical smoothing of the surface avoids such complications. CONCLUSIONS: The novel self-expandable silicone airway stent may be a promising addition to commonly used stent types. Short-term and medium-term management of fistulas, tumor surface bleeding, and strictures (malignant and benign) is satisfactory. Scanning electron microscopy of stents provides information on peculiar features of microstructure and material that may be of use in clinical research and technical innovation.

Adult↗
PubMed1997

Treatment of recurrent dislocation of the temporomandibular joint with type A botulinum toxin.

A case is reported of a 56-year-old woman who suffered from recurrent dislocations of the temporomandibular joint (TMJ) secondary to an exacerbated tetraspastic syndrome of multiple sclerosis. Following chemical denervation of the masseter and pterygoid muscles with injections of type A botulinum toxin, no further dislocations occurred for periods of up to four months. The treatment has been repeated five times. Some of the indications and possible adverse reactions to this therapy are discussed and comparisons made with other, conventional methods for managing recurrent dislocation of the TMJ.

Action Potentials↗