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J Müller

Publications and source records attributed to J Müller.

At least 361 records · Page 20Linked to original sources
PubMed1996

Prolonged expression of the c-kit receptor in germ cells of intersex fetal testes.

Stem cell factor (SCF) and its receptor Kit encoded by the c-kit proto-oncogene are crucial for the development and migration of primordial germ cells in rodents. The expression of Kit has been examined immunohistochemically in gonads obtained from five specimens of fetal tissues with intersex conditions which included 45,X/46,XY mosaicism; androgen insensitivity syndrome; and 46,XY/iso(p)Y mosaicism. Individuals with such disorders of sexual differentiation and Y-chromosome material carry a very high risk of developing testicular neoplasms. Fetal testicular germ cells of the intersex subjects expressed Kit at a later developmental age than controls, in which no Kit protein was detectable beyond the 15th week of gestation. This finding may indicate a disturbance of the chronology of germ cell development, or it may suggest a change of the regulation of c-kit expression in subjects with disorders of gonadal development.

Disorders of Sex Development↗
PubMed1996

[Hormonal premedication in endometrium ablation--results of a prospective comparative study].

In a prospective study in 40 patients the pretreatment for endometrial ablation with a gestagen (Orgametril 10 mg/die), danazol (600 mg/die) and an injection of a GnRH-analogon (Decapeptyl-Depot) was compared with a control group without pretreatment. The subjective estimation of the surgeon (endometrial thickness and depth of coagulation) showed a sufficient pretreatment in 90 % of all cases following danazol- and GnRH-analogon-pretreatment. In 90 % of the danazol- and GnRH-analogon pretreated group the histological findings showed also an atrophic or little proliferative endometrium. In a follow up of 6 months after endometrial ablation the highest amenorrhoea-rates were reached following danazol- and GnRH-analogon pretreatment. These two regimes should be used for the pretreatment for endometrial ablation.

Adult↗
PubMed1996

[Tragus perichondrium-cartilage island transplant in middle ear surgery. Method and results after 5 years].

Temporalis fascia remains the most widespread material for reconstructing the tympanic membrane in tympanomastoid surgery. If total or partial ossicular replacement prostheses are needed or pathology of the eustachian tube causes ventilation impairment, a more rigid transplant material is required. Between 1989 and 1994 perichondrium-cartilage composite grafts were used in a series of 597 cases of tympanomastoid surgery performed at the University ENT Clinic of Würzburg. The graft was taken from the tragus and prepared as a cartilage island with perichondrium attached to one side, the perichondrium-cartilage island transplant (PCI). If reconstruction of the ossicular chain was necessary, glass ionomer cement protheses (IONOS) were used. Closure of the tympanic membrane could be achieved in 90% of all cases. In those cases where ossicular chain reconstruction was postponed to a second procedure, closure of the drum was achieved in 96%. The audiological results of the different type III procedures were evaluated. By using the PCI technique a favorable closure of the air-bone gap to 10-25 dB was achieved, even in cases with advanced ear pathology technique and results are presented in detail.

Audiometry, Pure-Tone↗
PubMed1996

Growth, growth hormone and final height after BMT. Possible recovery of irradiation-induced growth hormone insufficiency.

The aim of the present study was to assess growth, final height, growth hormone (GH) secretion and growth factors after BMT including TBI in childhood. The median age of the 25 participants was 11.3 years at BMT, and a median of 7.5 years had elapsed since BMT. The median height standard deviation score (SDS) declined significantly from diagnosis until 4 years after BMT (n = 25, P = 0.015), and decreased 1.08 SDS from diagnosis until final height (n = 14, P = 0.030). Sitting height to standing height ratio was impaired, -0.64 SDS, P < 0.05. GH insufficiency was found in 32% at follow-up. Repeated assessments of GH production over the years indicated improvement in GH secretion in nine individuals. Evaluation of spontaneous 24-h GH secretion indicated a secretory pattern similar to controls, although the total amount of GH secreted was lower. Neither insulin-like growth factor-1 (IGF-1) nor IGF binding protein-3 (IGFBP-3) alone could be used as a marker of GH insufficiency. IGF-1 was low: -1.18 SDS; (P < 0.001). In conclusion, our study demonstrated the impact on growth, final height, body proportions, GH secretion and growth factors after BMT including TBI. We hypothesize that children who receive BMT at a younger age are more at risk of loss of final height and abnormal body proportions. Our data indicate that some improvement in GH production may occur over the years.

Adolescent↗
PubMed1996

[Diagnostic laparoscopy with mini-optics--initial experiences].

The use of a 1.2 mm microendoscope is compared to the conventional laparoscopy technique in this study. In 22 sterility patients and 23 patients suffering from chronic pelvic pain the high diagnostic value of the microendoscope is shown. Only in one case endometriosis (EEC I) is overseen. The diagnostic laparoscopy by the microendoscope is a new minimal invasive procedure which could be important as a screening method in future.

Adult↗
PubMed1996

[Intramyocardial electrocardiogram (IMEG) in diagnosis of humoral rejection after heart transplantation].

Measuring intramyocardial ECG amplitude is a clinical non-invasive procedure used for diagnosing rejection after heart transplantation. In recent years, as the importance of humoral mediated rejection has increasingly been recognized, the fact that endomyocardial biopsies often produce false negative results due to the absence of lymphocytic infiltrates has become a matter of concern. In order to test the reliability of IMEG diagnosis of this form of rejection, heterotopic neck-heart transplantation was performed on eight beagles which were previously sensitized through several skin transplantations. Over the course of the study IMEG registrations were performed daily as well as echocardiographic examinations to determine left ventricular wall thickness and maximal diastolic relaxation velocity. Donor-specific antibodies in serum (IgG, IgM) were also determined daily. Myocardial biopsies, performed once every 2 days, were examined for the presence of edema and lymphocytic infiltrate (according to the guidelines of the International Society of Heart and Lung Transplantation, ISHLT) and examined under immunofluorescent microscopy of IgG and IgM. Under triple drug immunosuppression with cyclosporine A, azathioprine, and cortisone accelerated rejection occurred on the fifth postoperative day (range: 4th-5th). All eight episodes were detected through IMEG diagnosis (sensitivity 100%), while the myocardial biopsies graded according to ISHLT guidelines indicated only one case of relevant lymphocytic infiltrate (Grade 3A) (sensitivity 12.5%). In each case rejection was recognized so early that it was possible to perform therapy with restitutio ad integrum. This proved that, as opposed to endomyocardial biopsy, IMEG diagnosis detected humoral mediated rejection early and with high reliability. Furthermore, the immediate recovery in IMEG during therapy indicates that the voltage decrease cause by rejection cannot be explained by an irreversible loss of myocardium (myocytolysis), but rather may be due to a quickly reversible functional impairment.

Animals↗
PubMed1996

[Sequential therapy concept in choledocholithiasis].

Of 4023 Patients with gallstone disease, 124 were treated for common bile duct stones by endoscopy (ERC/EPT). Stone clearance was completed in 81% of the patients. Due to a morbidity of 5.9% and a mortality of 0.6%, the concept of preoperative ERC followed by laparoscopic cholecystectomy seems to reduce risk for the patients.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1996

[PCR analysis of DNA in paraffin sections of malignant lymphomas].

The polymerase chain reaction was used to detect the clonal rearrangement of immunoglobulin heavy chain gene in paraffin embedded samples of human lymph nodes. We developed a sensitive and reliable method of the DNA isolation from 4-5 tissue sections, which enabled us to perform 50-100 PCR reactions. We compared the reactive lymph nodes and non-Hodgkin's malignant lymphomas using framework 3 and J region primers. PCR products were examined by agarose gel electrophoresis. The dominant 80-120 bp amplification product was found in all lymphoma samples. The samples of reactive nodes were negative.

DNA, Neoplasm↗
PubMed1995

Tissue culture loading test with storage granules from animal models of neuronal ceroid-lipofuscinosis (Batten disease): testing their lysosomal degradability by normal and Batten cells.

Storage granules (SGs) from ovine and canine models of Batten disease were found to be easily phagocytosed by four cell types studied. The cell types tested were human fibroblasts and peripheral monocytes (control and from a late infantile Batten disease patient), rat C6 cell line, and neonatal cardiomyocytes. The phagocytosed SGs elicited an increase in acid phosphatase activity which was localized in the phagolysosome. After phagocytosis SGs were followed for various times ranging from 7 to 21 days and were found to be of unchanged density (phase contrast), autofluorescence, and ultrastructural appearance. These findings point to their undergradability, or very low degree of degradability, in phagolysosomes in both normal or Batten cultured cells. The Batten disease SGs are not toxic and did not cause any adverse affect on the host cells. Either the normal clearance rate from lysosomes is too slow to be measured by this technique or subunit c accumulation in lysosomes need not result from a primary lysosomal protease defect. Subunit c may aggregate, because of the lack of some normally preventive factor, resulting in a physical barrier to the degradation of this highly apolar molecule.

Adult↗
PubMed1995

Transcriptional silencing by the Polycomb protein in Drosophila embryos.

Polycomb group (Pc-G) proteins act to keep homeotic genes stably and heritably silenced during Drosophila development. Here, it is shown that Polycomb (Pc), one of the Pc-G proteins, acts as a transcriptional silencer in Drosophila embryos if tethered to reporter genes by the DNA binding domain of GAL4 (i.e. as a GAL-Pc fusion protein). The results suggest that silencing by GAL-Pc requires the C-terminal portion of Pc, but not the chromodomain. If a pulse of Gal-Pc is provided, synthetic reporter genes are repressed, though only transiently. In contrast, reporter genes containing homeotic gene sequences remain stably and heritably silenced in a Pc-G gene-dependent fashion, even when GAL-Pc is no longer present. This implies that GAL-Pc recruits Pc-G proteins to DNA and suggests that maintenance of silencing requires the anchoring of Pc-G proteins to specific cis-regulatory sequences present in homeotic genes. The extent of DNA over which the Pc-G machinery acts is quite selective, as silencing established on one enhancer does not necessarily 'spread' to a juxtaposed synthetic enhancer.

ATP-Binding Cassette Transporters↗
PubMed1995

Transcriptional silencing of homeotic genes in Drosophila.

Homeotic genes are subject to transcriptional silencing, which prevents their expression in inappropriate body regions. Here, we shall focus on Drosophila, as little is known about this process in other organisms. Evidence is accumulating that silencing of Drosophila homeotic genes is conferred by two types of cis- regulatory sequences: initiation (SIL-1) and maintenance (SIL-M) elements. The former contain target sites for transient repressors with a highly localised distribution in the early embryo and the latter for constitutive repressors that are likely to be present in all cells. We discuss how SIL-1 elements may cooperate with SIL-M elements to promote formation of a silencing complex. We propose that this complex consists of specific non-histone proteins, the so-called Polycomb group proteins, and that it is anchored at SIL-M elements and at the promoter.

Animals↗
PubMed1995

DNA content and expression of tumour markers in germ cells adjacent to germ cell tumours in childhood: probably a different origin for infantile and adolescent germ cell tumours.

The origin of testicular germ cell tumours occurring during childhood is poorly understood. In adults, the classical seminomas and non-seminomas originate from carcinoma in situ of the testis, which can usually also be detected in seminiferous tubules adjacent to the tumours. In order to contribute with information regarding a possible association between carcinoma in situ and the childhood group of germ cell tumours, we investigated seminiferous tubules adjacent to 13 infantile yolk sac tumours, five infantile teratomas, and six adolescent germ cell tumours of various types, using morphological evaluation, immunohistochemical staining with markers for carcinoma in situ cells, and densitometric DNA measurement of the germ cells. We detected clear differences between the germ cell populations adjacent to adolescent and infantile germ cell tumours. The former were associated with both normal germ cells and carcinoma in situ cells, like germ cell tumours occurring in adult men. Although we were in doubt in two cases, the infantile cell germ cell tumours were in general not associated with carcinoma in situ cells. The aetiology of infantile yolk sac tumours and teratomas may therefore be fundamentally different from that of adolescent and adult germ cell tumours. The origin of yolk sac tumours and teratomas remains to be elucidated.

Adolescent↗
PubMed1995

Interaction of murine peritoneal leukocytes and mesothelial cells: in vitro model system to survey cellular events on serosal membranes during inflammation.

All serosal cavities including peritoneum are lined with a simple squamous mesothelium. Primary culture of murine mesothelial cells has been established to study their cellular interactions with peritoneal leukocytes. The mesothelial character was determined by the cytokeratin and vimentin expression. The mesothelial cells expressed ICAM-1 and CD44 molecules. The expression of ICAM-1, but not CD44, was significantly enhanced by the treatment with TNF-alpha (100 U/ml). We have also investigated possible influence of transforming growth factors, TGF-alpha (20 ng/ml) and TGF-beta (2 ng/ml), and epidermal growth factor (20 ng/ml). These factors were not found to modulate ICAM-1 or CD44 expression in vitro. During coculture experiments unstimulated mesothelial cells were almost nonadherent for both resident and elicited peritoneal mononuclear leukocytes for several hours. TNF-alpha or EGF pretreatment of mesothelial cells greatly enhanced their adhesive affinity to peritoneal mononuclear leukocytes, while TGF-beta pretreatment even reduced the low basal adhesion. Prolonged coculture for 3 weeks resulted in remarkable proliferation and differentiation of both resident and elicited monocytes/macrophages on the mesothelial surface. The stimulation of mesothelial cell culture with EGF resulted in the macrophage colony-stimulating activity (M-CSA) production. M-CSA was mainly due to M-CSF as confirmed with anti M-CSF monoclonal antibody; the residual M-CSA was not formed by GM-CSF. After several passages the mesothelial cells started to produce M-CSA spontaneously.

Animals↗
PubMed1995

Aldosterone: the minority hormone of the adrenal cortex.

In comparison with the glucocorticoids cortisol and corticosterone, the mineralocorticoid aldosterone is a minority hormone of the mammalian adrenal cortex, and its proper function is dependent upon protective physiological mechanisms. These include a particular site of aldosterone synthesis in zona glomerulosa cells as well as a complex multifactorial control system, which adapts aldosterone production to acute and chronic changes in body sodium and potassium contents, irrespective of pituitary ACTH secretion. In the course of the last few years, an important element of these mechanisms has been identified in the form of the enzyme involved in the final steps of aldosterone biosynthesis. In species such as the human, rat, and mouse, the conversion of deoxycorticosterone to aldosterone is catalyzed by an isozyme (CYP11B2) of cytochrome P450(11 beta) (CYB11B1). The gene encoding this enzyme is expressed only in the zona glomerulosa. Its transcription is enhanced by sodium deficiency and potassium intake, but is suppressed by long-term administration of high doses of ACTH. In contrast, the gene encoding CYP11B1, i.e., the major (non-aldosterone-producing) type of the enzyme, is expressed mainly in the zona fasciculata, and its expression depends on physiological concentrations of ACTH. In other animal species (cattle, pig), the major forms of cytochrome P450(11) beta have an inherent aldosterone-synthesizing activity, which is, however, selectively suppressed in mitochondria of zona fasciculata cells by yet unknown mechanisms.

Adrenal Cortex↗
PubMed1995

Atypical varicella-zoster virus infection in an immunocompromised patient: result of a virus-induced vasculitis.

We describe a patient with cutaneous T-cell lymphoma in whom persistent, painless, ecthymatous nodules developed as a result of a varicella-zoster virus infection. The localized infection occurred without a vesicular stage. Ultrastructural studies revealed a lack of epidermal involvement and massive varicella-zoster virus replication within endothelial cells, leading to an obliterative vasculitis. This suggests direct infection of dermal vessels from adjacent nerves, bypassing the epidermis, which is usually infected first in the classic infectious pathway during varicella-zoster virus reactivation from sensory nerves.

Blood Vessels↗
PubMed1995

Pubertal maturation of the internal genitalia: an ultrasound evaluation of 166 healthy girls.

Pelvic ultrasound is an important tool in the management of children with disturbances of pubertal development; interpretation requires an understanding of the normal relationship between maturation of internal genitalia and the appearance of secondary sex characteristics. We performed pelvic ultrasound examinations in 166 healthy females aged 6.4-25.4 years, and related uterine and ovarian volumes and size of follicles to age and pubertal stage. We demonstrated growth of the uterus and ovaries before the appearance of breast development and pubic hair growth. In prepubertal girls, uterine and ovarian growth was related to height (p = 0.008 and p = 0.010, respectively). From breast stages 1-5, median uterine and ovarian volumes increased from 1.6 ml to 43 ml, and from 1.2 ml to 7.3 ml, respectively (p < 0.0001). Uterine growth continued several years after menarche. Postmenarcheal uterine growth was related to the number of years after menarche (p < 0.001), but not to height, weight or age. Follicles were seen in 86% of prepubertal girls and in 99% of pubertal girls. Follicles up to 8 mm in diameter were observed in prepubertal girls. Maturation of the internal genitalia begins before the onset of clinical puberty, and extends well into the second decade.

Adolescent↗
PubMed1995

The sternocleidomastoid flap for treatment of a septic sternum defect.

After sternotomy for prosthetic repair of the ascending aorta and replacement of the aortic valve with a bioprosthesis in a 70-year-old woman local wound infection developed. Preliminary conservative treatment did not succeed. Because of the high risk for the patient due to local infection and partial exposure of the aortic prosthesis there was an indication for local flap surgery. Both healing of the infection and covering the prosthesis was achieved using a sternocleidomastoideus muscle flap.

Aged↗