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M Meissner

Publications and source records attributed to M Meissner.

At least 37 records · Page 2Linked to original sources
PubMed2000

Differential nuclear localization and nuclear matrix association of the splicing factors PSF and PTB.

A monoclonal antibody raised against nuclear matrix proteins detected a protein of basic pI in human nuclear matrix protein samples of various cellular origin. The ubiquitously occurring (common) nuclear matrix protein was identified as splicing factor PSF (PTB associated splicing factor). The interaction between the splicing factors PSF and PTB/hnRNP I was confirmed by co-immunoprecipitation from nuclear salt extracts. However, the nuclear localization of PSF and PTB and their distribution in subnuclear fractions differed markedly. Isolated nuclear matrices contained the bulk of PSF, but only minor amounts of PTB. In confocal microscopy both proteins appeared in speckles, the majority of which did not co-localize. Removing a large fraction of the soluble PTB structures by salt extraction revealed some colocalization of the more stable PTB fraction with PSF. These PTB/PSF complexes as well as the observed PSF-PTB interaction may reflect the previously reported presence of PTB and PSF in spliceosomal complexes during RNA processing. The present data, however, point to different cellular distribution and nuclear matrix association of the majority of PSF and PTB.

Antibodies, Monoclonal↗
PubMed1999

Reassembling proteins and chaperones in human nuclear matrix protein fractions.

To detect putative filament forming components, nuclear matrix proteins were searched for proteins extensively reassembling from urea solution. Eight proteins, ubiquitously occurring in various human cell types, but not apparent in the cytosol, were registered by means of two-dimensional gel electrophoresis. They consisted of a protein exhibiting a novel amino acid sequence; of nuclear lamin B2, RbAp46, and RbAp48; and of four as yet unknown proteins. Furthermore, partial sequencing, mass spectrometry, and immunodetection of proteins demonstrated the presence of molecular chaperones and protein folding catalysts in the nuclear matrix fractions. In addition to a TCP-1-related protein, certain members of the heat shock, PDI, and calreticulin family of proteins were detected. On the basis of the absence of several other heat shock proteins in the nuclear matrix fraction, a general contamination by cytoplasmic chaperones appears unlikely.

Amino Acid Sequence↗
PubMed1999

Volvox germline-specific genes that are putative targets of RegA repression encode chloroplast proteins.

In Volvox carteri, regA acts as a master gene to suppress all germ cell functions in somatic cells. Its product, RegA, has features of a transcriptional repressor. Here we report cDNA sequences representing 15 nuclear genes with properties expected of RegA targets: they are expressed strongly in germ cells and in regA-, but not regA+, somatic cells. Two of them encode polypeptides with no recognizable features, but ten (like three previously sequenced ones) encode chloroplast proteins of known function, and the remaining three encode putative chloroplast proteins of unknown function. This suggests that RegA blocks reproductive development in somatic cells by preventing chloroplast biogenesis, thereby making it impossible for the cells to grow enough to reproduce.

Adenosine Triphosphatases↗
PubMed1999

A study of 20 SLE patients with intravenous immunoglobulin--clinical and serologic response.

OBJECTIVE: To test the clinical response of systemic lupus erythematosus (SLE) patients to intravenous immunoglobulins (IVIg), and whether the clinical response of IVIg treatment in SLE is accompanied by modification of SLE-associated autoantibodies/antibodies (Abs) and complement levels. METHODS: Twenty SLE patients were treated with high-dose (2 g/kg) IVIg monthly, in a 5-d schedule. Each patient received between 1-8 treatment courses. They were evaluated for the clinical response, Systemic Lupus Activity Measure (SLAM) score before and after IVIg, levels of antinuclear antibody (ANA), dsDNA (double-stranded DNA), SS-A or SS-B, ENA (extractable nuclear antigens), C3 and C4 levels before and after the treatment, and before and after each treatment course. RESULTS: A beneficial clinical response following IVIg treatment was noted in 17 out of 20 patients (85%). Few clinical manifestations responded more to treatment: arthritis, fever, thrombocytopenia, and neuropsychiatric lupus. In 9 patients evaluated before and after IVIg, mean SLAM score decreased from 19. 3+/-4.7 to 4+/-2.9 (P<0.0001). There was a tendency towards abnormal levels of complement and Abs before IVIg courses among the treatment responders compared with the non-responders, and similarly the former tended to have normalization of their abnormal levels more than the latter. These differences were found statistically significant only with respect to C4 and SS-A or SS-B levels before IVIg courses. CONCLUSION: IVIg has a high response rate among SLE patients. A combination of clinical manifestations, Abs and complement levels may aid in the future in predicting who among SLE patients will benefit more from IVIg treatment.

Adult↗
PubMed1998

Catheter-directed thrombolysis in the treatment of phlegmasia cerulea dolens.

Phlegmasia cerulea dolens is a potentially devastating complication of extensive deep venous thrombosis for which there is currently no consensus for treatment. Heparin anticoagulation, surgical thrombectomy, thrombolytic therapy, fasciotomy, and amputation have each been advocated. We present two cases of phlegmasia cerulea dolens successfully treated with catheter-directed venous thrombolytic therapy.

Adult↗
PubMed1997

Two-dimensional electrophoresis reveals a nuclear matrix-associated nucleolin complex of basic isoelectric point.

A monoclonal antibody was raised against a salt-extractable fraction of nuclear matrix / intermediate filament scaffolds of polarized MDCK cells. The antibody recognized an approximately 100 kDa protein in total cell lysates and nuclear matrices of various human cells and tissues and stained nucleolar structures in immunofluorescence microscopy. By partial sequencing of five peptides derived from immunoprecipitated protein, the targeted antigen was found to be homologous to human nucleolin. After two-dimensional electrophoresis of total HeLa cell lysates, immunoreactive bands were detected at isoelectric point (pI) 5.5--6.1, characteristic for nucleolin, and at pI 8.5--9. Whereas the protein focusing at acidic pI was found in Triton X-100-soluble cellular fractions, the antigen focusing at basic pI was exclusively contained in the residual nuclear fraction and was solubilized upon treatment of nuclear matrices with RNAse. The component solubilized by RNAse treatment was still detected at basic pI in two-dimensional electrophoresis. However, upon immunoprecipitation of the antigen from the RNAse-released fraction in the presence of sodium dodecyl sulfate (SDS), the nuclear matrix-derived antigen was positioned at pI 5--6. The present data indicate that the nuclear matrix-bound nucleolin is associated with ribonucleoproteins and a basic component resisting dissociation under conditions of isoelectric focusing.

Animals↗
PubMed1997

[Ileostomy--cecal fistula--colostomy--which is the most suitable fecal diversion method with reference to technique, function, complications and reversal?].

In the literature the question as to what constitutes the most suitable faecal diversion procedure continues to be controversial. Between 1989 and 1994 at the Surgical Department of the University of Erlangen a total of 464 patients received intestinal stomas for a wide range of different indications. Of these procedures 41.6% (n = 193) were temporary diversion stomas (ileum n = 170, transverse colon n = 16, jejunum n = 4, sigmoid n = 2, ascending colon n = 1). Subsequently, 7.8% of the loop ileostomies and 9.7% of the loop colostomies needed revision for early or late complications. After reversal surgery none of the loop colostomies, but 2.5% of the loop ileostomies, developed complications needing operative treatment. On the basis of our own experience and the data reported in the literature it may be stated that both loop ileostomy and loop colostomy are effective faecal diversion procedures which, with appropriate bowel preparation and a meticulous surgical technique, can be reversed with a low incidence of complications. Both procedures, however, require careful preoperative planning, operative technique and care if complications are to be avoided. Used simply for the creation of a stoma, the laparoscopic approach offers certain advantages.

Cecostomy↗
PubMed1995

Coenzyme A glutathione disulfide. A potent vasoconstrictor derived from the adrenal gland.

The adrenal gland is involved in the regulation of vascular tone by secretion of vasoactive agents such as catecholamines, neuropeptide Y, or endogenous ouabain. A further potent vasoconstrictor is isolated from bovine adrenal glands and is identified by chromatography, mass spectrometry, UV spectroscopy, and enzymatic cleavage as coenzyme A glutathione disulfide (CoASSG). CoASSG is found in chromaffin granules of adrenal glands and is released from adrenal medulla slices by carbachol. At a concentration of 10(-12) mol/L CoASSG increases renal vascular resistance. Intra-aortic injection of 5 x 10(-10) mol CoASSG increases blood pressure in the intact animal. Besides its vasopressor properties, this substance potentiates the effects of angiotensin II on vascular tone. It is concluded that CoASSG could play a role in blood pressure regulation not only by direct effects but also by modulation of the action of angiotensin II.

Adrenal Glands↗
PubMed1994

The spectrum of blunt injury to the carotid artery: a multicenter perspective.

The relative infrequency of blunt carotid artery trauma prompted a multicenter review to determine the spectrum of injuries, treatment strategies, and neurologic outcome. During a six-year period, 60 carotid artery injuries from blunt mechanisms in 49 patients were treated at 11 institutions. There were 11 bilateral injuries. Injury mechanisms were diverse but involved motor vehicles in 35 (72%) patients. In 14 (29%) patients, significant neurologic deficits developed more than 12 hours after a normal admission neurologic examination. The diagnosis was confirmed by angiography in 42 (86%). Duplex ultrasound accurately demonstrated the arterial injury in 12 (86%) of 14 patients. Documented injuries included arterial thrombosis in 20 arteries, arterial dissection alone in 19, dissection with pseudoaneurysm in six, pseudoaneurysm alone in five, frank arterial disruption in seven, and carotid-cavernous fistula in three. Arterial dissection was managed nonsurgically in 15 (79%) of 19 cases, the majority with systemic anticoagulation. Arterial thrombosis was managed with supportive therapy alone for 16 (80%) of 20 arteries; most associated with fixed neurologic deficits. Pseudoaneurysm repair was performed for six (55%) injuries. Carotid-cavernous fistulas were treated in all three instances with balloon occlusion. Overall mortality was 16 of 49 patients (43%). Good neurologic outcome was achieved in 22 (45%) patients. We conclude that: (1) Neurologic symptoms may develop in a delayed fashion; prior clinical suspicion and diagnostic testing are essential; (2) arterial dissection without complete occlusion may effectively be managed by anticoagulation; (3) pseudoaneurysms in accessible anatomic locations can be repaired with good results; and (4) injuries with complete arterial thrombosis are associated with high mortality and poor neurologic outcome in proportion to the initial degree of neurologic impairment.

Adolescent↗
PubMed1992

Tuberculosis and the surgeon.

With the resurgence of active tuberculosis in the United States, surgeons may be called upon to participate in the management of primary tuberculosis as well as major complications of the disease. To define the role of surgery in the diagnosis and treatment of tuberculosis in the 1990s, a 5-year retrospective review of 121 tuberculosis patients requiring invasive procedures in the course of their work-up was performed. Mycobacterium tuberculosis was cultured in 68% of patients, and atypical mycobacteria in 19%. Tissue was required to achieve the definitive diagnosis in 36%. Of the 93 patients with pulmonary evidence of tuberculosis, 54% presented with a pulmonary complication, 19 of whom required operative intervention. Extrapulmonary tuberculosis affected 45% of patients, including nine with miliary tuberculosis. Patients testing seropositive for human immunodeficiency virus accounted for 11% of the patients seen, emphasizing that the re-emergence of tuberculosis is not confined to the immunosuppressed.

Adolescent↗
PubMed1992

Parathyroid hormone modulates the release of atrial natriuretic peptide during acute volume expansion.

In this study we investigated the effect of volume expansion on plasma and atrial concentrations of atrial natriuretic peptide (ANP) in the presence and absence of the parathyroid gland and under normocalcemic and hypocalcemic conditions. After volume expansion ANP concentration in plasma was significantly (p < 0.001) higher in intact (702 +/- 86 pg/ml) than in hypocalcemic parathyroidectomized (PTX) (271 +/- 38 pg/ml) rats. Plasma ANP of PTX rats rendered normocalcemic with oral calcium supplementation increased to 402 +/- 85 pg/ml after volume expansion. Results from this study suggest that parathyroid hormone (PTH) is required for augmented ANP secretion in response to acute volume loading and alterations of extracellular calcium may modulate volume-induced ANP release in PTX rats. We would discuss that a parathyroid gland-cardiac atria interaction exists and that changes in serum level of PTH may play a role in the regulation of fluid homeostasis via ANP secretion.

Animals↗
PubMed1992

[In-vitro research on the marginal adaptation of composites with the use of different dentin adhesives].

The aim of this investigation was the check and evaluation of 7 various dentin adhesives regarding their influence on the connection between dentin resp. enamel and composite filling. For that cylindrical cavities in dental crowns (enamel cavities) and roots (dentin cavities) were prepared and treated with dentin adhesives and composite materials. One part of the test teeth was subjected to loads storage in aqueous solution and thermocycling. The marginal adaptation of the composite filling was checked by means of the dye penetration test. The evaluation was made after cutting the teeth in the stereo microscope TECHNIVAL 2 (Carl Zeiss Jena) at 16-resp. 25 magnifications and defined criteria. The fillings in cavities bound by enamel exhibited a very good marginal adaptation of the composite. The location of the dentin cavity (crown or root dentin) had no significant influence on the fitting of the filling. A clear penetration of dye could be observed with the fillings in the dentin with and without adhesives, which considerably intensified after thermocycling. Best results with regard to the marginal adaptation were obtained with Scotchbond 2, Mirage-Bond and Cavex-Clearfil-Newbond. A restoration without a marginal gap was not possible.

Composite Resins↗
PubMed1991

Duplex scanning for arterial trauma.

Duplex sonography was evaluated as a potential screening examination for arterial trauma in 89 patients with 93 injuries, mostly to the extremities (n = 74) or the cervicothoracic region (n = 17). Among 60 scans performed solely because of wound proximity to nearby vascular structures, 4 (6.7%) were positive. Thirteen of 19 (68%) scans performed for clinical indications were positive. Six of 12 (50%) postoperative studies were abnormal, and each of 4 arterial injuries followed serially remained stable. Four false-negative duplex scans (4.3%) were recorded; no major arterial injuries were missed, and no false-positive studies were noted. Duplex sonography is rapid, noninvasive, inexpensive, and portable. Since it also appears to be reliable in diagnosing and localizing sites of arterial disruption, duplex scanning may be of value in screening patients with trauma for the presence of occult vascular injuries.

Adolescent↗
PubMed1991

A pertussis outbreak in a Wisconsin nursing home.

The epidemiologic features and clinical spectrum of pertussis in the elderly are poorly understood. In October 1985, the Wisconsin Division of Health investigated an outbreak of pertussis in residents of a nursing home in rural Wisconsin. Clinical information and nasopharyngeal swab and acute- and convalescent-phase serum specimens were obtained from all consenting residents and employees. Of 105 residents, 38 (36.2%) were seropositive, including four who were culture-positive for Bordetella pertussis. Culture-positive residents (age range, 52-81 years) had cough lasting 43-54 days. Three of these residents had paroxysmal cough, and all four had cough that interrupted sleep; none of the residents had cough with apnea or vomiting, and all recovered without sequelae. Of six seropositive residents with clinical pertussis, five lived on the south wing of the facility. Of 104 employees, 8 (7.7%) were seropositive, but none were culture-positive for B. pertussis. The higher attack rate for residents and the clustering of clinical cases were consistent with ongoing transmission within the nursing home.

Aged↗