Correlation between bending of the VM region and pathogenicity of different Potato Spindle Tuber Viroid strains

Only 40 of the 359 nucleotides of Potato Spindle Tuber Viroid (PSTVd) represent the virulence-modulating (VM) region. Minor sequence variations in this domain distinguish mild from severe and even necrotic strains. Our recent hypothesis (Owens RA et al., 1996, Virology 222:144-158) that these differences result in varying degrees of bending of this part of the molecule could be tested experimentally. By in vitro transcription and partial double-strand formation, three types of model RNAs were prepared and subjected to electrophoresis in polyacrylamide gels: (1) Fragments representing the VM regions of six different PSTVd strains; (2) control fragments containing a bulge-loop as a rigid bend or an internal loop as a point of increased flexibility; and (3) dsRNAs of 36, 39, and 43 bp as length standards. Migration anomalies in gels of increasing percentage were evaluated and resulted in the following conclusions. In the absence of Mg2+, the VM regions differ only in terms of flexibility. Addition of Mg2+ induces conformational changes in these RNAs. All strains but Mild exhibit a rigid bend, and the angle of bending increases monotonically with the pathogenicity of the strain. The data are discussed in terms of a mechanism of pathogenicity, that protein-binding to the VM region is the primary pathogenic event.

[Clinical and nuclear magnetic resonance tomography diagnosis of glenoid labrum injuries]

PURPOSE

Clinical and radiological evaluation of labral tears remains challenging. It has been shown that intravenous administration of contrast agents produces an MR arthrographic effect without the need for intraarticular injection. This is the first study evaluating this new technique of indirect MR arthrography in diagnosis of glenoid labrum tears.

METHODS

28 patients with clinically suspected labral injuries were prospectively investigated (1.5 Tesla, flexible surface coil). A native MR exam of the shoulder (transverse and oblique-coronar orientation, T1-weighted spin-, proton density- and T2*-weighted gradient echo sequences) and indirect MR arthrography (transverse and oblique-coronar orientation, fat-suppressed T1-weighted spin-echo sequences, intravenous injection of gadopentetate dimeglumine [0.1 mmol/kg], followed by 10-15 min of joint movement) were performed. Results were confirmed by arthroscopy and/or open surgery. Additionally sensitivity evaluation of clinical tests for investigation of labral tears were performed.

RESULTS

Indirect MR-Arthrography improved delineation of the glenoid labrum and hyaline cartilage significantly (p < 0.05). Sensitivity and specificity of indirect MR arthrography in diagnosis of labral injuries were 90% and 89% respectively, compared to 79% and 67% of the native MR exam. The reliability of the checked clinical tests is not sufficient enough to determine labral lesions (predictive value between 50 and 70%).

CONCLUSION

Indirect MR-arthrography is a promising non-invasive technique in the evaluation of the glenoid labrum.

[Autonomous thyroid adenoma. Value of thallium scintigraphy and pathology]

Clinical, biological, scintigraphic (99mTc, 123I, 201Tl) and histological data were reviewed in 90 patients operated for autonomous adenomas (hot nodules). Analysis of the data gave the following results: 74.4% of the nodules were solitary and 25.6% occurred in a multinodular goiter (MNG). Hyperthyroidism (FT3-, FT4-, TSH < 0.1) was present in 44% of solitary nodules and in 15% of MNG. 16.6% of patients were euthyroid, and 22.2% had a TSH < 0.1 and normal free hormones. The 201 Tl scintigraphy, performed instead of the administration of exogenous TSH, showed and uptake of Tl in the remainder of the thyroid. Four types of 201Tl uptake were observed in the pathological lobe: type 1: homogeneous uptake: type 2: heterogeneous uptake and hyperfixation in the nodule; type 3: faint uptake and hypofixation in the nodule; type 4: faint and very heterogeneous uptake. Histological analysis of the nodules showed 32.2% of follicular adenomas, 25.6% of MNG and 42.2% of colloid nodules. Among these lesions, 70% showed histological signs of hypermetabolism (resorption vesicles ...). Multivariate analysis of these data clearly demonstrates the need to redefine the clinical, biological, scintigraphic and histological concepts of autonomous adenomas. On the other hand, 91.6% of follicular adenomas show a type 2 Thallium uptake (22/24). On basis of these results, we prefer to operate these patients rather than to treat them by 131I or by percutaneous injection of ethanol.

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.

Epistaxis and diabetes mellitus in an obese woman

Images

A cytogenetically anchored genetic map of bovine chromosome 1 obtained by integrating flow-sorted chromosome-derived microsatellite markers into the international bovine map

A genomic library was constructed from a peak of flow-sorted bovine chromosomes 1 + X after PCR amplification. Forty-three bovine chromosome 1 microsatellites were isolated, genetically mapped and integrated in the international genetic map. In addition, BAC clones from a goat BAC library were identified for five markers (DVEPC119, INRA011, BM4307, KAP8 and MAF64). These goat BACs could be mapped by FISH onto bovine chromosome 1 to bands 1q44-->q45, 1q25, 1q21, 1q12 and 1q14-->q21, respectively. This map reduces the average interval between consecutive markers on the international bovine genetic map from 5.5 cM to 2.5 cM, and provides a good starting point for positional cloning projects in cattle, sheep or goats.

Onchocerca ochengi: assessment of the Simulium vectors in north Cameroon

In the savanna areas of tropical Africa, cattle are frequently infected with the filaria Onchocerca ochengi. This parasite is closely related to Onchocerca volvulus, the causative agent of human onchocerciasis (river blindness), and is capable of developing in the same vector, Simulium damnosum s.l. In North Cameroon, where both O. ochengi and O. volvulus are endemic, we carried out a field study (reported in this and 2 following papers) to examine to which extent the transmission of the 2 parasite species overlap and what influence this has on the epidemiology of human onchocerciasis. In this paper we report our experiments to determine which of the S. damnosum species in North Cameroon act as vectors of O. ochengi, how efficiently they do so and whether other Simulium species play a vector role. To this end, infected cattle were exposed near 5 rivers in different geographical areas. Among 14 Simulium species identified as aquatic and/or adult stages at these rivers, only 6 (S. squamosum, S. damnosum s.s., S. sirbanum, S. bovis, S. wellmanni and S. hargreavesi) were found to bite cattle in important numbers in at least 1 of the sites. The 3 species of the S. damnosum complex were all capable of ingesting microfilariae (mf) of O. ochengi and developing a proportion of them to infective larvae (L3). Whereas S. squamosum and S. damnosum s.s., the prevailing vectors in the Guinea and Sudan savanna respectively, showed a high vector competence (17% of ingested mf developed to L3), S. sirbanum, which was much rarer in both areas, appeared to have a much lower susceptibility (2%). Other boophilic Simulium species were only seen in certain sites and seasons, being either incapable of ingesting important numbers of O. ochengi mf from body regions where these mf were abundant (S. bovis, S. hargreavesi); not able to support the development of ingested mf to L3 (S. wellmanni), or bit cattle preferentially in the ears, where O. ochengi mf do not occur (S. hargreavesi). We conclude that in North Cameroon members of the S. damnosum complex are the only important vectors of O. ochengi, with S. squamosum and S. damnosum s.s. being the main vectors.

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.

[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.

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.

[The effect of temperature and humidity on breath samples. Measurement of breath ethanol concentration in artificially respirated patients]

When looking for the possible cause of distortions in values measured for the determination of breath ethanol concentration (BEC) in artificially respirated patients, consideration must be given to the humidity and temperature of the gas examined. In the present study, the effects of humidified and warmed and of dry and cold air on the accuracy of a newly developed BEC measuring device, as compared to a reference model and to a conventional system, were examined in a lung model.

METHODS

A temperature-regulated pediatric incubator was used containing a 10 I gas reservoir and a breath humidifier with temperature regulated water bath. This setup provided constant temperature and humidity in the gas examined during measurement period. In the 'expiration' the air was directed from the breath humidifier through a measuring unit via a 'mouthpiece' into the reference system (Alcotest 7110, Dräger Inc., Lübeck) and then out. The measuring unit consisted of sensors for the temperature and relative humidity, and of a connector for the three sample extraction systems (PES). PES I was the conventional system with a 100-cm gas-sample pipe (Alcomed 3010), PES II the newly developed system (AlcoMed 3011, both from Envitec, Wismar) with a 10-cm gas-sample pipe, and PES III with a 20-cm heated gas-sample pipe. During 'inspiration' 2 l of air was fed into the system to rinse the measuring unit and to fill the reservoir. 61 measurements were performed with dry and cold air, and 71 with humidified and warmed air, in the course of which the ethanol concentration was increased from 0 to 1.5/1000. Data were evaluated using regression analysis and the Bland & Altman method.

RESULTS AND CONCLUSIONS

The constancy of the values set for temperature, relative humidity and absolute humidity in the lung model was given for all measurements. In the dry and cold air, the results from all three test systems coincided almost perfectly with the reference values. The measured BEC in the humidified and warmed air using sample-extraction systems II and III corresponded to a high degree with the reference, while in the case of PES I, only a moderate linear correlation was achieved. The temperature and humidity of the expired gas during artificial respiration influence the gas samples extracted for the purposes of BEC measurement. Newly developed sample-extraction systems II and III coincide with the reference system, even under respiration-simulated gas conditions.

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.

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.

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.

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.

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.

[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.

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.

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.

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.