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H Müller

Publications and source records attributed to H Müller.

At least 541 records · Page 30Linked to original sources

In situ hybridization analysis of cytomegalovirus lytic infection in Kaposi's sarcoma associated with AIDS. A study of 14 autopsy cases.

Cytomegalovirus (CMV) was assayed by in situ hybridization with commercially available biotin-labeled CMV-DNA probes in 45 formalin-fixed paraffin-embedded autopsy specimens with Kaposi's sarcoma from 14 cases of the acquired immune deficiency syndrome (AIDS). In seven of the 14 cases, a few scattered hybridizing cells were detected in Kaposi's sarcoma, but not all specimens from the same case showed such cells. Most of the positive cells were peculiarly swollen and not typical of Kaposi's sarcoma cells. All positive cases had at least some CMV-infected organs with typical cytomegalic cells containing nuclear inclusions while five of the 7 negative cases revealed no CMV-infected tissue by conventional light microscopy. Our results suggest that this in situ hybridization procedure using biotin-labeled DNA probes only reveals generalized CMV infection that is a consequence of impairment of immune mechanisms in AIDS patients.

Acquired Immunodeficiency Syndrome↗

Susceptibility of chicken blood lymphoblasts and monocytes to infectious bursal disease virus (IBDV).

PHA-M stimulated lymphoblasts obtained from peripheral blood and separated from small lymphocytes by X 1 g velocity sedimentation, unstimulated blood lymphocytes, monocytes and cells isolated from the bursa of Fabricius of chickens, were infected in vitro by the pathogenic strain CU-1 of infectious bursal disease virus (IBDV). Six hours after infection 32.5 per cent of the bursal cells reacted immunocytologically with IBDV antiserum and had high infectivity titers in plaque assays. Separated lymphoblasts showed a marked lower degree of virus replication and only 2.5 per cent reacted positively when studied by immunocytology, while monocytes ranged between these two cell types with regard to both the degree of virus replication and the positive reaction with IBDV antiserum. Small lymphocytes, however, were found to be totally resistant to IBDV infection. When studied by electron microscopy, virus particles arranged in a crystalloid pattern could only be detected in bursal cells. The results of this study indicate that proliferating lymphoid cells at a certain stage of cellular differentiation are the target cells for IBDV, and that in infected chickens monocytes may play a role in the spreading of the virus.

Animals↗

Pathogenic and structural properties of wild type infectious bursal disease virus (IBDV) and virus grown in vitro.

Large plaque (LP) and small plaque (SP) variants of Infectious Bursal Disease Virus (IBDV) which are formed in vitro after serial passages in CE-cells at low or high multiplicities of infection were tested for their pathogenic properties in susceptible chickens. LP virus caused clinical manifestations and destruction of the Bursa of Fabricius (BF) without killing the animals. No signs of a disease appeared after infection with SP virus, and only limited necrotic foci developed in the BF. Coinfection with the SP variant and the highly pathogenic wild type (wt) virus reduced mortality and the severity of the disease. In contrast to the SP variant, which forms incomplete particles of low density, with one or the other of the two genomic RNA segments missing, the two RNA segments characteristic for IBDV were present in approximately equal amounts in wt particles with a buoyant density of 1.29 g/ml isolated from the BF. In spite of an almost total replacement of one of the two major structural polypeptides with a molecular weight of 32 kd by a 28 kd protein, infectivity in this low density fraction was only slightly reduced. This finding underlines the importance of the type of post-translational modification in lymphoid cells or fibroblasts.

Animals↗

Familial and histological analyses of 138 breast cancer patients.

A histological analysis was conducted in 138 female breast cancer patients, and the results were classified in accordance with "Histological Typing of Breast Tumours" (WHO, Geneva 1981). Since about half of these tumors showed more than one histological type of carcinoma, a simplified classification system with four groups was adopted. When patients were categorized according to the number and degree of kinship of their relatives with breast cancer, no specific association with the histological types was found. Familial tumors also encompassed a wide spectrum of histopathologic diagnoses. This suggests the absence of a histological marker in familial breast cancer. Pedigrees of all the patients were then analyzed, special emphasis being placed on relatives suffering from the same and other malignancies. It was found that 13.8% of the probands had at least one first-degree relative with breast cancer and that, compared with the tumor spectra in the male and female population, there was a significantly higher number of esophageal carcinomas in the fathers, of stomach cancers in the uncles and grandfathers, of brain tumors in the mothers, and of sarcomas in the brothers. An accumulation of the same tumors, especially stomach cancer and tumors related to the SBLA syndrome, was observed in families of index patients with tubular or medullary breast cancer. The SBLA syndrome is a complex familial cancer syndrome characterized by a proclivity to Sarcomas, Breast cancers, brain tumors, Lung and laryngeal cancers, leukemia, and Adrenocortical carcinomas.

Adenocarcinoma↗

Results of systemic chemotherapy of advanced bladder carcinomas (phase II study).

At the time of operation advanced carcinomas of the urinary bladder often have developed subclinical metastases. In 20 patients with metastases, inoperable carcinoma of the bladder responded to chemotherapy with a combination of adriamycin and 5-FU. 55% of the patients experienced either a complete or incomplete remission, which lasted long in some cases. In the future, suitable combinations of chemotherapeutics could participate in improving the prognosis of advanced carcinoma of the urinary bladder.

Antineoplastic Combined Chemotherapy Protocols↗

Evoked muscle action potentials from regenerated rat tibial and peroneal nerves: synthetic versus autologous interfascicular grafts.

To compare peripheral nerve regeneration across bridging synthetic tubular implants with ordinary autologous transplantation, we recorded evoked muscle action potentials 3 months after transection, following direct stimulation of rat tibial and peroneal nerves. Significantly, with autologous transplantation we were able to evoke compound muscle action potentials in all but one case (this having a 15-mm gap). Pooling the groups together, compound action potentials could be recorded in 15 of 45 cases that had regenerated through 13- to 16-mm gaps. Potentials in the synthetic implant-treated group tended to show more temporal "scattering" in the late phases of the EMG response. No differences were found in compound muscle action potential amplitudes and duration, or terminal motor conduction velocity, between both experimental groups, between different artificial tubuli, between different gap lengths, or between the peroneal and tibial nerves. The overall values were remarkably lower than in nontransected controls, about 25% of the compound muscle action potential normal amplitude voltage and 60% of the terminal motor conduction velocity.

Action Potentials↗

Nerve regeneration in synthetic and autogenous interfascicular grafts. II. Morphometric analysis.

Cross-sectional areas at different levels, number of axons, maximal diameters, and number and maximal diameters of vessels were measured comparing autologous transplants with synthetic implants and nonlesion controls in a rat nerve regeneration model. The corresponding electrophysiologic data have been reported earlier in this journal. Although similar in many aspects, transplants led to the overall more reliable and slightly superior results, still lacking a substantial percentage of numerical qualities found in normal nerve, at least within the 3-month regeneration in this study.

Animals↗

The two segments of the infectious bursal disease virus genome are circularized by a 90,000-Da protein.

The genome of infectious bursal disease virus (IBDV) consists of two segments of double-stranded (ds)RNA with molecular weights of 2.2 X 10(6) and 1.9 X 10(6) Da, respectively. After treatment of IBDV particles with proteinase K in the presence of sodium dodecyl sulfate (SDS), linear dsRNA molecules are released from the virus particles. However, after heating of virus particles at 100 degrees for 3 min in 1.5% SDS, without the protease, dsRNA-protein complexes can be seen under the electron microscope: Knob-like proteinaceous structures are linked to the ends of the dsRNA molecules of either size class which are circularized to form individual rings. A 90,000-Da IBDV structural polypeptide, the only protein encoded by the smaller genome segment, has been demonstrated to remain firmly linked to the IBDV genome under these conditions. No functional data exist about this circularizing protein; it is a probable candidate for an RNA-dependent RNA polymerase or an assembly protein for the two dsRNA segments. At high particle concentrations, or when the preparations are allowed to stand for several hours before spreading, these complexes tend to aggregate to form flower-like structures.

Infectious bursal disease virus↗

Primary intraventricular traumatic hemorrhage.

The history of five patients, having developed intraventricular bleeding following head injury, was reviewed. Only two patients survived, one of whom eventually lapsed into a persistent vegetative state. The only patient showing good recovery was an 8-year-old girl. Primary traumatic intraventricular hemorrhage should be considered a rare, but serious entity with a very poor prognosis.

Adult↗

Properties of RNA polymerase activity associated with infectious bursal disease virus and characterization of its reaction products.

An RNA-dependent RNA polymerase activity of infectious bursal disease virus (IBDV) could be demonstrated without any special treatment of the virus particles. Ca2+ ions had to be removed from the reaction mixture. Mg2+ (4 mM) was essential for the polymerase activity which was optimal at pH 8.5 and 40 degrees C. The RNA products synthesized in vitro were 24S single-stranded (ss) RNA and 14S double-stranded (ds) RNA which remained closely associated with IBDV particles and which could only be released by proteolytic degradation of the virus. The positions of the two bands in polyacrylamide gels and hybridization with virion RNA identified the 14S RNA as the two genomic dsRNA segment. The 24S ssRNA also formed two bands, did not self-anneal, hybridized with virion RNA, and induced in vitro translation of virus-specific polypeptides. Therefore, this product was considered to be newly transcribed mRNA.

Animals↗

Low-grade adenocarcinoma of the oral cavity. A comparison between the terminal duct and the papillary type.

Fifteen cases of a recently-described type of adenocarcinoma of salivary gland tissue are reviewed. Lesions are variously designated polymorphous low-grade adenocarcinoma, low-grade papillary adenocarcinoma, terminal duct carcinoma and lobular carcinoma. Tumours were divided into those with papillary structures (8 cases) and those without (7 cases), respectively low-grade papillary adenocarcinoma (LGPA) and terminal duct adenocarcinoma (TDA). Mean age of TDA-cases was 59.1 years; of the LGPA-cases 64.2-years. TDA's occurred anywhere in the mouth whereas LGPA's occurred in all but two cases in the hard palate. Three of the TDA-patients exhibited recurrent tumours as did 1 of the LGPA-patients. Metastatic disease was shown by 2 of the LGPA-patients. It is concluded that TDA and LGPA show sufficient difference in histopathological and clinical aspects to justify separating them. Both lesions are equally prone to local recurrence but it is the papillary type that can give origin to local and distant metastatic disease. The relation between LGPA and TDA on the one hand and adenoid cystic carcinoma on the other is discussed, leading to the conclusion that although there are some similarities, differences prevail.

Adenocarcinoma, Papillary↗

Sequential or single pulse defibrillation? Investigations towards energy reduction in experimental animals.

With introduction of the automatic implantable cardioverter-defibrillator for treatment of medically refractory ventricular arrhythmias, many investigations are focussing on possibilities of reducing the energy necessary for defibrillating the heart to obtain a more adequate size and a longer durability of the generator. Several studies favour the sequential pulse delivery, using three electrodes, either endocardial, epicardial or subcutaneous plates, to improve defibrillation performance of low energy shocks. However, the validity of this conclusion remains equivocal since two different electrode configurations were used for single and sequential defibrillation. In the present study the influence of sequential pulse delivery, pulse sequence and resultant current pathways on defibrillation energy requirements were examined in comparison with single-shocks between the same epicardial electrode configuration as well as four orthogonally positioned patches. The energy requirement for 100% efficiency could be reduced by sequential pulsing with a time interval of 1 msec thus yielding significant superiority compared to single pulse defibrillation using three electrodes. The same reliable defibrillation and reduced threshold has been obtained by using four electrodes and one single shock. The addition of a third electrode alone had no influence on the energy requirements. Therefore, we have to discuss a different electrophysiological mechanism for sequential defibrillation than for single shocks with an extended current distribution over the heart using four electrodes. Possibly the action potential of the single cell of the fibrillating heart is of interest in reflecting the efficiency of sequential pulse defibrillation. By influencing the action potential pharmacologically in some animals, the optimal time interval for double shocks could be extended up to 7 msec.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Laser-assisted trachea anastomoses in dogs.

Tracheal anastomoses are known to be related to special surgical risks. We performed laser-assisted trachea anastomoses in 10 Beagle dogs, using an Argon-laser system and a handheld quarz fiber for energy transmission. All animals showed an uneventful postoperative course without signs of infection, air-leakage or respiratory impairment. Pathologic examination revealed no significant stenosis but a normal reconstruction of the tracheal endothelium and a normal woundhealing with only an increased connective tissue reaction. Because of the lower tensile strength of laser-assisted anastomoses in general, three adapting absorbable sutures should be left in situ to increase the resistance against mechanical stress. Under these circumstances laser-assisted anastomoses seem to be a promising additional method in the field of tracheal reconstruction and transplantation.

Anastomosis, Surgical↗

[In families of ovarian cancer patients, breast cancer in females and colorectal cancers in males are overrepresented].

A detailed tumour-related family history was obtained from 30 women with histologically verified epithelial ovarian carcinomas. 46% of the anamnestic tumour diagnoses were also verified by obtaining copies of histology reports. Breast cancer was overrepresented among the female relatives and colorectal cancer among the male relatives. This study demonstrates that persons at high cancer risk as well as tumour-prone families of interest for aetiological cancer research can be identified by the simple method of obtaining a family history.

Adult↗

Immunochemical determination of an initial step in thymine dimer excision repair in xeroderma pigmentosum variant fibroblasts and biopsy material from the normal population and patients with basal cell carcinoma and melanoma.

A monoclonal antibody specific for u.v.-induced thymine-thymine dimers in single-stranded DNA has been used in an enzyme immunoassay to investigate the loss of antigenicity associated with repair of this lesion in the first 2 h following 10 J/m2 254 nm radiation. Variances of +/- 10% for the method and +/- 6.5% for individuals were established using primary cultures of biopsies from healthy individuals. No differences in the rate of loss of antigenicity was observed between 20 normal lymphocyte samples and 10 normal skin biopsies. Of three xeroderma pigmentosum (XP) variant cell lines tested, GM3617 could not be distinguished from normal cells but GM1227 and GM3053 showed lower rates of loss than any of the healthy samples. When the group mean values were compared there was no significant difference between normals and biopsies from sun-shielded skin areas from 16 basal cell carcinomas but similar material from 10 melanoma patients showed a significantly reduced (P = 0.001) rate of loss of antigenicity. Since the rate of loss of antigenicity in normal and XP variant cells reflected their relative abilities to perform unscheduled DNA synthesis, our results suggest that some melanoma patients may also have a minor deficiency in an early stage of excision repair.

Adult↗

Analysis of the autoimmune response in an 'in situ' carcinoma of the testis.

Immune response in a patient with an in-situ seminoma of the testis was studied. Immunohistochemical examination of the testicular biopsy demonstrated remarkable intracellular and membraneous accumulation of IgG antibodies in the atypical spermatogonia. Using FITC-conjugated Concanavalin A, an abnormally high binding of Concanavalin A was detected in the transformed cells. Circulating antibodies directed against an antigenic determinant (60 kD) which is expressed on normal human spermatozoa and lymphocytes were found only in the patient's serum and not in 500 control sera. The role and possible diagnostic value of this autoimmune reactivity in testicular malignancies are discussed.

Adult↗