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A Schmitz

Publications and source records attributed to A Schmitz.

At least 73 records · Page 4Linked to original sources
PubMed1998

Characterization of reciprocal translocations in pigs using dual-colour chromosome painting and primed in situ DNA labelling.

We report the use of dual-colour chromosome painting to determine the exact nature of certain chromosome rearrangements observed in the pig (Sus scrofa domestica). The chromosomal abnormalities were detected by GTG- and RBG-banding techniques. The initially proposed interpretations were: (1) rcp(6;13)(p1.5;q4.1); (2) rcp(11;16)(p1.4;q1.4); (3) rcp(6;16)(p1.1;q1.1); (4) rcp(13;17)(q4.1;q1.1); (5) rcp(6;14)(q2.7;q2.1); (6) rcp(3;5)(p1.3;q2.3); (7) rcp(2; 14)(q1.3;q2.7); (8) rcp(15;17)(q1.3;q2.1). Hybridizations were carried out with biotin- and digoxigenin-labelled probes obtained by priming authorizing random mismatches polymerase chain reaction (PARM-PCR) amplification of porcine flow-sorted chromosomes. In some cases, i.e. (1), (4), (5), (6), (7) and (8), the fluorescence in situ hybridization (FISH) results allowed confirmation of the interpretations proposed with classical cytogenetic methods. Chromosome painting proved the reciprocity of the translocation in cases (1), (6) and (8), whereas modifications of the formula were proposed for case (2). Primed in situ DNA labelling (PRINS) experiments have also been carried out in case (3) using a primer specific for the centromeres of acrocentric chromosomes (first experiment) or a primer specific for the centromeres of a subset of meta- and submetacentric chromosomes including chromosome 6 (second experiment). It allowed us to demonstrate that the breakpoints occurred in the centromeric region of chromosome 16 and in the p. arm of chromosome 6, just above the centromere.

Animals↗
PubMed1998

Spinal epidural haematoma in haemophilia A.

We report on a 27-year-old male Caucasian with severe haemophilia A who presented with acute onset of neck pain with cervical nerve root irritation, due to a spinal epidural haematoma. His past medical history revealed carrying of a moderate weight as a possible traumatic mechanism. Under immediate factor VIII replacement therapy complete remission of the symptoms was achieved within several days. The diagnosis of spinal epidural haematoma and complete resorption was revealed by initial and follow-up magnetic resonance imaging studies of the cervical spine. Having reviewed the literature on spinal epidural haematoma, we present an overview of the treatment and outcome as regards haemophilia.

Adult↗
PubMed1998

Comparative karyotype of pig and cattle using whole chromosome painting probes.

The extent and distribution of conserved chromosomal segments between pig and cattle chromosomes were established using hybridization of porcine chromosome painting probes on bovine metaphases. A total of 44 segments of conserved synteny were identified, resulting in a nearly complete coverage of the bovine karyotype. This study provides new data on chromosome evolution of mammals.

Animals↗
PubMed1998

Renal structural changes in insulin-dependent diabetic patients with albuminuria. Comparison of cases with onset of albuminuria after short or long duration.

The large interindividual variation in diabetes duration until the onset of nephropathy is partly unexplained. This study was performed to compare renal structure in insulin-dependent (IDDM) patients who had developed signs of nephropathy after a short or long duration of diabetes. Renal biopsies were obtained from 17 IDDM patients, with albumin excretion rate 20-300 microg/min and normal blood pressure. Six patients had <25 years duration ("short-term", early onset of microalbuminuria) and eight patients had duration >30 years ("long-term", late onset of microalbuminuria). Biopsies were obtained 18 months after entry into a study testing the effect of low-dose antihypertensives. Parameters characterizing diabetic glomerulopathy were significantly increased in IDDM patients compared with those in 17 living donors: Basement membrane thickness, mean and (CV): 591 nm (0.17) vs 320 nm (0.12), mesangial volume fraction per glomerulus 0.27 (0.19) vs 0.19 (0.10), matrix volume fraction per glomerulus 0.16 (0.20) vs 0.097 (0.22), matrix star volume 38.5 microm3 (0.43) vs 13.9 microm3 (0.31), (p<10(-4) for each). Comparison of short vs long-term patients showed no significant differences in glomerulopathy parameters, glomerular volume or extracellular material per glomerulus, whereas the fraction of occluded glomeruli was significantly increased in long-term patients. A close correlation obtained between fraction of occluded glomeruli and glomerular filtration rate (r=0.72, p= 0.001). Glomerular occlusion occurred unrelated to the severity of diabetic glomerulopathy. It is suggested that diabetic macroangiopathy and arteriolar hyalinization may play an important role in the renal function of patients with slow development of nephropathy.

Adult↗
PubMed1998

[Measuring breath alcohol concentration during artificial ventilation. Model studies of the effect of temperature and humidity on measurements by various sampling systems].

The present paper examined the question as to the extent to which the taking of gas samples for the purpose of measuring the breath alcohol concentration (BAC) in the expired air of patients on artificial respiration is influenced by temperature and humidity. For this purpose a lung model standardized at different alcohol concentrations was used, in which the temperature (T: 25, 30 and 35 degrees C) and the relative humidity (RH: 50, 75 and 95%) were varied.

Breath Tests↗
PubMed1997

Complex protein binding to the mouse M-lysozyme gene downstream enhancer involves single-stranded DNA binding.

The mouse M-lysozyme downstream enhancer has been previously characterized on several levels of gene regulation. The enhancer was co-localized with a DNase I hypersensitive site in the chromatin of mature macrophages, the in vivo interaction of transcription factor GABP with the enhancer core (MLDE) demonstrated binding being restricted to mature macrophage cells, and analysis of the MLDE methylation state revealed a correlation between demethylation of CpG dinucleotides and the in vivo GABP binding. Here, we analyzed in detail the full-length enhancer in addition to the core element. We identified a total of nine binding sites for nuclear factors. Most of these factors are found ubiquitously in all cell types tested. These factors include several unknown proteins as well as the transcription factor NF-Y. In addition, three binding sites for a new single-stranded DNA binding protein were found. The presence of this factor in mature macrophages correlates with the in vivo DNA melting of one of the binding sites and with the enhancer strength.

Animals↗
PubMed1997

Cis-elements required for the demethylation of the mouse M-lysozyme downstream enhancer.

The mouse lysozyme downstream enhancer was previously colocalized with the DNase I-hypersensitive site in the chromatin of mature macrophages. This hypersensitive site was shown to be macrophage differentiation-dependent. Demethylation of CpG sequences within the enhancer is correlated with lysozyme expression in mature macrophages. Binding of the GABP heterotetrameric transcription factor to the enhancer core element (MLDE), only seen in vivo on the demethylated MLDE element in macrophages, is inhibited by DNA methylation. Here, we analyzed the DNA sequences required for demethylation. In electrophoretic mobility shift experiments we found that in addition to the complete methylated MLDE the hemimethylated form of the lower strand inhibits GABP binding as well. Therefore, GABP is unlikely to be the mediator of demethylation. In addition, we show by stable DNA transfections of methylated mouse lysozyme enhancer sequences that MLDE-flanking sequences are required for demethylation. We narrowed down these DNA elements to two short regions of 163 and 79 base pairs on either side of the MLDE, each of which is sufficient to mediate demethylation of the GABP site.

Animals↗
PubMed1997

Concerted nonsyntenic allelic losses in hyperploid hepatocellular carcinoma as determined by a high-resolution allelotype.

Although the occurrence of loss of genetic material in hepatocellular carcinoma (HCC) has been documented both by cytogenetic analysis and by monitoring of allelic losses, a global overview of the extent and frequency of deletion occurring throughout the genome is not yet available. To contribute to this information, DNAs extracted from flow-sorted aneuploid nuclei from HCC and matched normal DNAs were typed for 275 microsatellite loci that were distributed along the autosomes. An average of 190 (69%) informative loci per case were generated on 48 HCC. Complete loss of heterozygozity in the tumor DNA was observed for 15.6% of the typed loci. The chromosome segments that were most frequently affected by deletion were: 8p (60%), 17p (48%), 1p (44%), 4q (42%), 16p (40%), 16q (39%), 6q (35%), 9p (30%), and 13q (29%). On average, 8 of the 39 chromosome segments studied per tumor carried at least one locus that demonstrated loss of heterozygosity (ie., the fractional allelic loss was 0.21). Groups of concerted nonsyntenic losses were observed for 16p and 1p and for 16p and 4q. The location of putative tumor suppressor genes on the most frequently deleted regions was confirmed and, in some cases, refined.

Adult↗
PubMed1997

Hypersensitivity reactions to parenteral lipid solutions.

In cancer patients, hypersensitivity reactions to adjunctive medications are easily mistaken for cytostatic toxicities. We report on three patients with systemic reactions (flush, dyspnea, tachycardia, hypotension, back pain) to a lipid emulsion containing long chain fatty acids (LCT). Reexposure to LCT and exposure to MCT (medium chain fatty acids) solutions of slightly different composition--no soybean lecithin used as an emulsifier--were well tolerated. These data suggest that traces of soybean proteins are the allergenic agents. Therefore, hypersensitivity to concomitant medications, including parenteral nutrition, has to be considered in oncologic patients demonstrating severe systemic reactions to intravenous therapy.

Drug Hypersensitivity↗
PubMed1997

Microalbuminuria, blood pressure, metabolic control, and renal involvement: longitudinal studies in white non-insulin-dependent diabetic patients.

In the present paper, longitudinal studies in non-insulin-dependent diabetes mellitus (NIDDM) dealing with risk factors, especially microalbuminuria, blood pressure, and glycemic control, and the course of the kidney function are addressed. The definition of microalbuminuria, limits for abnormal albuminuria, and possible causes of microalbuminuria in NIDDM are discussed. Microalbuminuria is a major independent risk marker for early mortality, and new studies indicate that even "high normoalbuminuria" carries a risk. Furthermore, risk markers agreed on among various studies include apart from abnormal albuminuria, age and preexisting cardiovascular disease, whereas there is some inconsistency concerning glycemic control, lipoproteins, and even hypertension. People with microalbuminuria, NIDDM patients as well as nondiabetics, share an increased prevalence of atherosclerosis and its risk factors as well as an increased TER(alb). Albuminuria in NIDDM may thus have two different causes: general vascular disease and diabetic glomerulopathy. The clinical course of renal function is with large interindividual variation in both patients with or without overt proteinuria. Systolic blood pressure, glycemic control, and level of albuminuria appear to determine the deterioration in kidney function and progression of albuminuria, and to influence the overall prognosis, thus being obvious items for intervention. Long-term intervention studies demonstrating improved survival are, however, still awaited.

Albuminuria↗
PubMed1997

The clinical course of renal function in NIDDM patients with normo- and microalbuminuria.

OBJECTIVES: To assess the clinical course of renal function in relation to risk factors in NIDDM patients with normo- and microalbuminuria. DESIGN: Prospective clinical study. SETTING: Outpatient diabetic clinic. SUBJECTS: Thirty-two NIDDM patients with normo- or microalbuminuria followed for (mean (range)) 5.5 (3.3-7.5) years. MAIN OUTCOME MEASURES: Glomerular filtration rate, urinary albumin excretion rate, blood pressure, lipids, glycaemic control. RESULTS: The mean rate of decline of glomerular filtration rate was -1.2 +/- 2.3 (mean +/- SD) (95% confidence intervals: -2.0--0.3) mL min-1 1.73 m-2 year-1 (p = 0.009). A considerable interindividual variation was observed (range -6.7 to + 3.4 mL min-1 1.73 m-2 year-1). No difference was found between normo- and microalbuminuric patients (-1.2 +/- 0.5 vs. -1.0 +/- 0.7 mL min-1 1.73 m-2 year-1) or between patients with and without anti-hypertensive treatment (-1.7 +/- 0.7 vs. -0.7 +/- 0.4 mL min-1 1.73 m-2 year-1). By multiple linear regression analysis the fall rate of glomerular filtration was determined by the mean glomerular filtration rate level (p = 0.036). Analysis of patients without antihypertensive treatment revealed that urinary albumin excretion rate and HbA1c levels significantly determined the fall rate of glomerular filtration (P < 0.001 and = 0.014). CONCLUSIONS: The average decline in renal function of these normo- and microalbuminuric NIDDM patients was not increased as compared to the age related fall rate of healthy subjects but varied markedly. Low glomerular filtration rate is associated with a higher fall rate. In patients without antihypertensive treatment higher urinary albumin excretion rate, and poorer glycaemic control are factors associated with an increased fall rate of glomerular filtration.

Aged↗
PubMed1997

[Intraneural ganglion of the peroneal nerve].

The intraneural ganglion of the peroneal nerve is a rare lesion. The differential diagnosis includes lesions of the knee especially the tendinopathia of the knee flexors. Clinical examination, electrophysiological investigations, ultrasound imaging and magnetic resonance tomography will establish the diagnosis. We report a case in which an artificial puncture of the ganglion caused a temporary peroneal palsy. Surgical procedure led to complete restoration of the nerve function.

Cysts↗
PubMed1997

Prediction of the biologically active sites in eclosion hormone from the silkworm, Bombyx mori.

The structure-activity relationship of eclosion hormone from the silkworm, Bombyx mori, was analyzed. First, the probable active residues in silkworm eclosion hormone and also tobacco hornworm eclosion hormone were predicted by the average distance map method. To examine the contributions of those residues to the activity of silkworm eclosion hormone, Gly-substituted mutants for those predicted residues were produced by site-directed mutagenesis and their activities were evaluated by a bioassay. Finally, Glu12, Met24 and Phe25 were estimated to be the crucial residues for the eclosion hormone activity. The possibility of the development of a blocker of an eclosion hormone receptor on the basis of the present work is also discussed.

Amino Acid Sequence↗
PubMed1997

Association of the TNFa2 microsatellite allele with the presence of colorectal cancer.

Independently, our two groups collaborating in this report performed association studies to consider the influence of the TNF region within the human MHC on the presence of colorectal cancer. In the Glasgow Study, 84 colorectal cancer patients were compared with 91 controls at the TNFa microsatellite locus. Analysis of individual alleles by Fisher's exact test revealed a significant overrepresentation of the TNFa2 allele in the colorectal cancer group, after correcting for multiple comparisons. In the Essen Study, 47 colorectal cancer patients were compared with 117 matched controls, and the hypothesis of TNFa2 overrepresentation in colorectal cancer was confirmed. These data provide evidence for the involvement of the TNF locus in the pathogenetic etiology of colorectal cancer.

Alleles↗