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A Köhler

Publications and source records attributed to A Köhler.

At least 19 recordsLinked to original sources
PubMed1995

Clinical and molecular genetic findings in five patients with Miller-Dieker syndrome.

Five patients with type 1 lissencephaly, typical features of Miller-Dieker syndrome and apparently normal karyotypes were investigated for microdeletions in chromosome 17p13.3. Analysis of loci D17S5 and D17S379 by polymerase chain reaction and fluorescence in situ hybridization revealed a deletion in three cases. No deletion was observed in the remaining two cases. Given the almost identical clinical picture of the five patients, the great variation in the molecular findings argues against Miller-Dieker syndrome being a contiguous gene syndrome.

Abnormalities, Multiple↗
PubMed1995

Assignment of the dystonia-parkinsonism syndrome locus, DYT3, to a small region within a 1.8-Mb YAC contig of Xq13.1.

A YAC contig was constructed of Xq13.1 in order to sublocalize the X-linked dystonia-parkinsonism (XDP) syndrome locus, DYT3. The contig spans a region of approximately 1.8 Mb and includes loci DXS453/DXS348/IL2R gamma/GJB1/CCG1/DXS559. For the construction of the contig, nine sequence-tagged sites and four short tandem repeat polymorphisms (STRPs) were isolated. The STRPs, designated as 4704#6 (DXS7113), 4704#7 (DXS7114), 67601 (DXS7117), and B4Pst (DXS7119) were assigned to a region flanked by DXS348 proximally and by DXS559 distally. Their order was DXS348/4704 #6/4704 #7/67601/B4Pst/DXS559. They were applied to the analysis of allelic association and of haplotypes in 47 not-obviously-related XDP patients and in 105 Filipino male controls. The same haplotype was found at loci 67601 (DXS7117) and B4Pst (DXS7119) in 42 of 47 patients. This percentage of common haplotypes decreased at the adjacent loci. The findings, together with the previous demonstration of DXS559 being the distal flanking marker of DYT3, assign the disease locus to a small region in Xq13.1 defined by loci 67601 (DXS7117) and B4Pst (DXS7119). The location of DYT3 was born out by the application of a newly developed likelihood method for the analysis of linkage disequilibrium.

Adult↗
PubMed1995

[Transanal rectal advancement flap versus mucosa flap with internal suture in management of complicated fistulas of the anorectum].

A prospective study was carried out on 55 patients with complicated anal fistulas (41 transsphincteric, 5 suprasphincteric and 9 rectovaginal) to evaluate the value of two sphincter-conserving techniques with primary occlusion of the internal ostium and endorectal advancement flap (group A, n = 34) or mucosal flap (group B, n = 21). Ten of the patients had Crohn's disease. Both techniques consist in one-stage fistulectomy without drainage of the intersphincteric space. The inflamed proctodeal and granulation tissue was carefully cleared. The site of the former primary orifice of the fistula was adapted by means of two or three peranally performed single stitches. The peranally applied suture included the layers of the internal anal sphincter muscle only. A mobilized flap of rectal wall (group A) and rectal mucosa and submucosa (group B) about 4 cm x 3 cm in size was stitched below the muscular sphincter. The perianal part of the wound was left to heal by second intention. Postoperatively there were 16 cases of suture leakage (23.5% in group A, and 38% in group B), and 19 patients (26% or 47% in both groups) had to have revision surgery because of recurrent fistula or sutur leakage; 2 patients (3.6%) developed incontinence with intermittent fecal soiling. Complete incontinence was not observed in any patient. No significant difference in clinical and functional results was determined between the two groups.

Anal Canal↗
PubMed1995

[Media sclerosis: a case of pseudohypertension].

A 51-year-old diabetic showed symptoms of a hypertensive crisis with a systolic blood pressure above 300 mmHg. The antihypertensive therapy failed and the Doppler-pressure values were also too high for all limb arteries. Duplex-sonography and soft-x-ray examination showed a mediasclerosis of arms and legs. The true pressure, measured at the still compressable arteries of the fingers was relatively low. There was symptomatic improvement after completion of the antihypertensive therapy.

Arm↗
PubMed1994

Treatment of high anal fistulae by primary occlusion of the internal ostium, drainage of the intersphincteric space, and mucosal advancement flap.

In a prospective study on 224 patients with so-called high-fistula in ano (189 transsphincteric, 35 suprasphincteric) the long-term results of a sphincter-saving operation technique were assessed. The follow-up period was 1 to 7.5 years. This technique consists of one-stage fistulectomy as well as of drainage of the intersphincteric space by internal sphincterotomy. The site of the former primary orifice of the fistula is adapted by multiple peranally performed single stitches, including mucosal advancement flap distal to the original fistulous opening. Postoperatively, 24 cases of suture leakage occurred (9% with the transsphincteric and 20% with the suprasphincteric fistula). 27 patients developed late complications like fistula recurrences or combinations of fistula and anal abscess (10.7% with the transsphincteric and 19.9% with the suprasphincteric fistula). Anal manometry was carried out preoperatively as well as postoperatively. A significant decrease in the postoperative resting pressure compared to the preoperative value was determined. The two fistula groups differed statistically both with regard to the resting pressure and the contraction pressure. Significant impairment of continence developed in 21% of patients with transsphincteric fistula but in 43% of patients with suprasphincteric fistula (intermittent fecal spoiling/use of perineal pads). The total percentage of complications rose with the number of previous fistula operations.

Drainage↗
PubMed1994

Molecular basis and diagnosis of neurogenetic disorders.

Over the past few years, molecular neurogenetics has developed into one of the most promising and active research fields. The new discipline applies modern molecular genetic techniques to the investigation of classical neurological disorders. In the following article, a definition of neurogenetic disease is introduced, the molecular basis of four groups of neurogenetic disorders is described and recent diagnostic developments are presented. The first group of diseases is caused by trinucleotide expansions. "Expanding" trinucleotide repeats were not known to occur in any species until about three years ago. Today, disorders such as Huntington's disease, spinocerebellar ataxia type 1, fragile X mental retardation, spinobulbar muscular atrophy and myotonic dystrophy are all known to be caused by the expansion of trinucleotides. The second group is characterized by chromosomal deletions or uniparental disomies. Lissencephaly and the Miller-Dieker syndrome, Prader-Willi and Angelman syndromes and Duchenne and Becker muscular dystrophies belong to this category. The third group includes those neurogenetic disorders that are mainly caused by point mutations such as the X-linked leukodystrophies, including Pelizaeus-Merzbacher disease and adrenoleukodystrophy, Charcot-Marie-Tooth syndrome type 1, familial forms of amyotrophic lateral sclerosis, several types of craniosynostoses and some CNS tumor syndromes. Finally, Alzheimer's and Parkinson's disease are discussed as representatives of group four, i.e. genetically heterogeneous neurological disorders.

Animals↗
PubMed1994

Familial half cryptic translocation t(9;17).

A half cryptic translocation t(9;17) (p24.2; p13.3) was detected in a large family by fluorescence in situ hybridisation. Unbalanced karyotypes resulted either in lissencephaly and early death or in mental retardation, microcephaly, high arched palate, and deformities of the vertebrae. Some of the features observed in affected persons are characteristic of known syndromes involving either 17p or 9p.

Adolescent↗
PubMed1994

[Indications and technique of retro-ileal colorectal anastomosis after expanded left-sided hemicolectomy].

Retroileal colorectal anastomosis following a complete resection of left-sided colon was performed in 28 patients with differing diseases of the colon. Concerning the rate of leakage of anastomosis dextraposition appeared to be as safe as conventional techniques. Turnbull originally created this technique to perform a tension-free anastomosis after resection of the left sided colon. In doing so the retained colon reduces the risk of incontinence especially seen with elderly patients.

Adult↗
PubMed1994

[Postoperative results of colostomy and ileostomy closure. A retrospective analysis of three different closure techniques in 182 patients].

On 182 patients undergoing closure of a stoma 149 colostoma and 33 ileostoma closures were performed. The complication rate with 5-8% leakages in site of the anastomosis comes out very high. Furthermore the surgeon has to count with a high quote of wound infections. The complication rate of the ileostoma closures with 18% appears distinctly higher than those of the colostoma closures with 6.7%. One patient belonging to the group of colostoma closures died. The extraperitoneal closure with Turnbull's procedure was conspicuous by reason of the high rate of enterocutaneous fistulas and the high rate of incisional herniations, so that this method should only be used in special cases. We routinely enforce an intraperitoneal closure of the stoma. The resection with an end-to-end anastomosis in comparison to the suture of the anterior wall implies in our opinion neither advantages nor disadvantages.

Adult↗
PubMed1993

Regional assignment of the human homeobox-containing gene EN1 to chromosome 2q13-q21.

The human homeobox-containing genes EN1 and EN2 are closely related to the Drosophila pattern formation gene engrailed (en), which may be important in brain development, as shown by gene expression studies during mouse embryogenesis. Here, we have refined the localization of EN1 to human chromosome 2q13-q21 using a mapping panel of rodent/human cell hybrids containing different regions of chromosome 2 and a lymphoblastoid cell line with an interstitial deletion, del(2)(q21-q23.2). This regional assignment of EN1 increases to 22 the number of currently known genes on human chromosome 2q that have homologs on the proximal region of mouse chromosome 1.

Animals↗
PubMed1993

Intranuclear filaments containing a nuclear pore complex protein.

Nuclear pore complexes (NPCs) are anchoring sites of intranuclear filaments of 3-6 nm diameter that are coaxially arranged on the perimeter of a cylinder and project into the nuclear interior for lengths varying in different kinds of cells. Using a specific monoclonal antibody we have found that a polypeptide of approximately 190 kD on SDS-PAGE, which appears to be identical to the recently described NPC protein "nup 153," is a general constituent of these intranuclear NPC-attached filaments in different types of cells from diverse species, including amphibian oocytes where these filaments are abundant and can be relatively long. We have further observed that during mitosis this filament protein transiently disassembles, resulting in a distinct soluble molecular entity of approximately 12.5 S, and then disperses over most of the cytoplasm. Similarly, the amphibian oocyte protein appears in a soluble form of approximately 16 S during meiotic metaphase and can be immunoprecipitated from egg cytoplasmic supernatants. We conclude that this NPC protein can assemble into a filamentous form at considerable distance from the nuclear envelope and discuss possible functions of these NPC-attached filaments, from a role as guidance structure involved in nucleocytoplasmic transport to a form of excess storage of NPC proteins in oocytes.

Animals↗
PubMed1993

The pH as an important determinant of sperm-mucus interaction.

OBJECTIVE: To determine the clinical significance of endocervical mucus pH on sperm-mucus interaction during infertility investigation. PATIENTS AND MATERIAL: Two hundred sixteen couples with a median duration of infertility of 4 years (range, 1 to 19 years) presenting at the infertility unit of the Women's University Hospital of Heidelberg, Germany. MAIN OUTCOME MEASURES: Determination of endocervical pH by colorimetric and electrometric measurement and correlation of results with the outcome of postcoital testing (PCT) and other parameters of infertility investigation (semen and cervical mucus [CM] quality, microbial colonization of cervix and ejaculates, medical history, hormonal status, and specific medication) and the subsequent fertility in a prospective study. In vitro experiments with the sperm-cervical mucus penetration test (SCMPT) used as biological model. RESULTS: The colorimetric determination of endocervical mucus pH is an easy method, suitable for routine clinical use, correlating significantly with electrometric measurement of pH. Median pH was 7.0 (range, 5.4 to 8.2). The mucus pH was significantly related with the results of PCT, even when mucus and semen variables were taken into account. No significant relationship was seen between the cervical index and mucus pH and the microbial colonization of cervix and ejaculates. The pH of endocervical secretions correlated with the peripheral hormonal status: low pH levels were significantly more frequent in patients with hyperandrogenemia, indicated by high testosterone and/or dehydroepiandrosterone sulfate levels before medication was started, and in hyperandrogenemic patients treated with dexamethasone than in the other women. Oral administration of estrogens led to a subtle alkalinization of the CM. With regard to subsequent fertility 6 months after pH testing, the pregnancy rate was significantly lower in women offering reduced mucus pH on occasion of the PCT in the group of couples with primary infertility and in couples with oligozoospermia of the male partner. The significant influence of pH on sperm-mucus interaction was confirmed in vitro with the SCMPT. CONCLUSIONS: The results indicate that the pH of the CM, easily determined with pH indicator paper, is an important parameter of mucus quality with significant influence on spermatozoal viability in CM, which correlates with peripheral hormonal status and can be affected by oral medication with estrogens. Therefore the routine determination of pH on occasion of the PCT is recommended during infertility investigation.

Adult↗
PubMed1991

Lysosomal perturbations in fish liver as indicators for toxic effects of environmental pollution.

1. Lysomones play a key role in liver injury in fish caused by organic and inorganic xenobiotics. The lysosomal stability test was transferred to fish liver with the aim of testing responsive and practicable methods for biological-effects monitoring. 2. A two-step response of lysosomes in fish liver could be discerned, reflected by the activity (number and size of lysosomes) and the injury (membrane destabilisation) of the lysosomal detoxifying system. 3. Significant differences, with respect to lysosomal enlargement, membrane stability and pathological lipid accumulation, were found along a pollution gradient throughout the year. 4. The lysosomal tests clearly reflect the breakdown of the adaptive capacity of the fish liver to toxic injury. Therefore, a test battery measuring lysosomal perturbations should be recommended for the biological-effects monitoring.

Animals↗
PubMed1989

Investigations of chorionic villi after chorionic villus sampling (CVS). Correlation of morphological with clinical and laboratory data.

This report documents the first 262 cases of chorionic villus sampling (CVS) performed in parallel with cytogenetic and morphological investigations. Histomorphological examination of these CVS specimens gave suitable results in about 96% (251 cases). Of the latter, 201 samples (80.1%) exhibited villi and 176 (70.1%), maternal tissue. Viability and maturation of the chorionic villi were determined light microscopically even in cases with few villus trees. Smooth avascular villi with poorly defined margins observed under an inverted microscope, less than 10 mitoses after short-term incubation, and reduced growth of cell cultures were significantly correlated with sampling at the chorion laeve by means of histomorphologic criteria. Villi from cases exhibiting cytogenetically proved chromosomal abnormalities were characterized by molar degeneration or stromal fibrosis, or both, in 4 out of 9 cases, including 3 mosaics. In early abortions (within 3 weeks after CVS), an unexpectedly high rate of pathohistological changes within maternal tissue was evident. These results need further confirmation by investigation of a greater number of samples with immunohistochemical and morphometric methods.

Adult↗
PubMed1988

Feto-maternal transfusion after chorionic villus sampling. Evaluation by maternal serum alphafetoprotein measurement.

The alphafetoprotein (AFP) concentration in maternal serum was determined before and after chorionic villus sampling (CVS). A significant increase of 20% or more in the pre-CVS level was noted immediately after sampling in 59% of 837 pregnancies indicating some degree of feto-maternal haemorrhage. The increase in the AFP concentration in maternal serum was correlated with the weight of the tissue sample but not with the number of sampling attempts. A correlation of AFP increase and frequency of spontaneous abortions following CVS was suggested only in the group with an AFP increase of more than 100% or with a continuing rise in the first hour following CVS. CVS in early pregnancy obviously did not interfere with maternal serum AFP screening for neural tube defects in the second trimester. Although AFP measurement before and after CVS seems to have no immediate diagnostic application, in the research phase of CVS it may help to identify those procedures that are the least traumatic.

Abortion, Spontaneous↗