Proliferative and cytotoxic response of human natural killer cells exposed to transporter associated with antigen-processing-deficient cells.

In transporter associated with antigen-processing (TAP)-deficient patients affected by a severe downmodulation of human leucocyte antigen class I (HLA-I) molecules, natural killer (NK) cells have an increased expression of the inhibitory receptor CD94/NKG2A. Focusing our attention on NK cells, we have investigated the phenotype, function and proliferative response of peripheral blood lymphocytes (PBLs) derived from healthy donors after coculturing with TAP (T2)- or HLA-I-deficient (721.221) cell lines and their related HLA-I-expressing transfectants (T3 and DT360, respectively). After 4 days, NK cells cocultured with T2 cells had a threefold increased CD94 expression compared to NK cells cocultured with T3. This increase was due to proliferation of the CD56brightCD94bright subset. In contrast, expression of other inhibitory receptors [killer cell immunoglobulin (Ig)-like receptors] was variable during time and was not related to HLA-I molecules expressed by stimulating cells. Similar results were obtained using HLA-I-deficient cells (721.221). The PBLs cocultured for 4 days with T2 cells displayed enhanced cytotoxic responses. The results suggest that CD56brightCD94bright NK cells are induced to proliferate and kill in response to a TAP-deficient environment. The changes seen in the NK-cell compartment were partially contributed by T lymphocytes present in the coculture. These data could explain the increased CD94 expression and autoimmune manifestations observed in TAP-deficient patients.

Effects on quality of life, symptoms and daily activity 6 months after termination of an exercise training programme in heart failure patients.

BACKGROUND: Exercise training in heart failure patients improves exercise capacity, physical function, and quality-of-life. Prior studies indicate a rapid loss of these effects following termination of the training. We wanted to assess any sustained post-training effects on patients global assessment of change in quality-of-life (PGACQoL) and physical function. METHODS: Fifty-four stable heart failure patients were randomised to exercise or control. The 4-month exercise programme consisted of bicycle training at 80% of maximal intensity three times/week, and 49 patients completed the active study period. At 10 months (6 months post training) 37 patients were assessed regarding PGACQoL, habitual physical activity, and dyspnea-fatigue-index. RESULTS: Both post-training patients (n=17) and controls (n=20) deteriorated PGACQoL during the 6-month extended follow-up, although insignificantly. However, post-training patients improved PGACQoL slightly but significantly from baseline to 10 months (P=0.006), differing significantly (P=0.023) from controls who were unchanged. Regarding dyspnea-fatigue-index, post-training patients were largely unchanged and controls deteriorated insignificantly, during the extended follow-up as well as from baseline to 10 months. Both groups decreased physical activity insignificantly during the extended follow-up, and from baseline to 10 months post-training patients tended to decrease whereas controls significantly (P=0.007) decreased physical activity. CONCLUSION: There was no important sustained benefit 6 months after termination of an exercise training programme in heart failure patients. A small, probably clinically insignificant sustained improvement in PGACQoL was seen in post-training patients. Controls significantly decreased the habitual physical activity over 10 months and post-training patients showed a similar trend. Exercise training obviously has to be continuing to result in sustained benefit.

Expression of Ly49A on T cells alters the threshold for T cell responses.

In this study we investigated the balance between activating and inhibitory signals during T cell activation. We have used transgenic mice in which CD8+ T cells expressed an inhibitory receptor, Ly49A, and a specific activating alphabeta TCR. This TCR recognizes an lymphocytic choriomeningitis virus peptide in combination with H-2Db. We observed a quantitative influence on cellular responses that depended upon the activating signals received through the TCR and the inhibitory signals received through Ly49A. By varying the peptide concentration given to stimulating cells or target cells, we could adjust the amount of ligand available to trigger the TCR. At low doses of peptide, Ly49A-expressing T cells were unresponsive on target cells that expressed H-2Dd, but responded against target cells without H-2Dd. However, this inhibition could be overcome by increasing the peptide concentration or by addition of anti-Ly49A F(ab')2 fragments. Thus, rather than behaving as simple "off" switches, our data indicate that Ly49 receptors modulate T cell signaling so that higher amounts of activating signals are required for effector-cell responses.

Pressurised liquid extraction of polycyclic aromatic hydrocarbons from contaminated soils.

The reliability and efficiency of the pressurised liquid extraction technique (PLE) for extracting polycyclic aromatic hydrocarbons (PAHs) from contaminated soil has been investigated. Experimental design was used to study the influence of seven extraction variables (sample load, solvents used, solvent ratios, pressure, temperature, extraction time, and rinse volume). The results show that large sample loads in combination with small solvent volumes may result in low extraction efficiency. They also indicate that the recovery of low-molecular-mass PAHs is reduced by low extraction temperatures. The exact settings of the other variables are, however, less significant for the extraction efficiency. Repeated extractions at optimised settings of the tested variables show that PLE is an exhaustive extraction technique that generally results in high yields. In addition, extraction of a certified reference material (CRM 103-100) revealed that the method is both accurate and precise. Another finding was that adding the internal standard on top of the soil in the extraction cell causes considerable over-estimation of the concentrations when large samples are extracted with small solvent volumes. This is because the PLE-cell resembles a chromatographic column, so compounds added to the top of the soil layer have a longer distance to travel through the soil compared to the average distance of the native compounds, which are distributed evenly throughout the column. We therefore recommend that the internal standard should be added to the extract immediately after the extraction or, alternatively, carefully mixed with the sample prior to extraction.

Ly49A expression on T cells alters T cell selection.

Ly49 receptors are inhibitory receptors expressed on subsets of both NK cells and NK1.1(+) T cells. The function of these receptors on NK cells is believed to be important in maintaining self-tolerance, yet their role on T cells is unclear. In this report we investigated how an Ly49A transgene alters T and NK cell development in an in vivo environment, where a ligand for Ly49A is expressed. Ly49A transgenic mice that co-expressed an MHC ligand for Ly49A, H-2D(d), developed a severe inflammatory disorder that resulted in death within the first weeks of age. T cells expressing forbidden TCR V(beta) chains were found both in the thymus and periphery of transgenic mice, while non-transgenic littermates had successfully deleted these T cell subsets. These data indicate that the expression of Ly49A on T cells could alter T cell selection and allow survival of potentially self-reactive T cells.

ACE inhibition with ramipril improves left ventricular function at rest and post exercise in patients with stable ischaemic heart disease and preserved left ventricular systolic function.

AIMS: To assess the effects of 6 months intervention with +ramipril on resting and post exercise left ventricular function in patients with stable ischaemic heart disease and preserved left ventricular systolic function. METHODS AND RESULTS: Patients (n=98, age 65+/-9 years, 37% women) were randomized to double-blind treatment with ramipril 5 mg. day(-1)(n=32), ramipril 1.25 mg. day(-1)(n=34), or placebo (n=32). Resting and post maximum exercise echocardiography/Doppler examinations were performed at baseline and after 6 months. Changes over 6 months in resting transmitral E-wave deceleration time (Edt) and Edt adjusted for heart rate (Edt/RR) differed between the ramipril 5 mg, ramipril 1.25 mg, and placebo groups: Edt 24+/-82, -1+/-69, and -29+/-64 ms, respectively, P=0. 012; Edt/RR 30+/-105, 2+/-61, and -28+/-69 ms, respectively, P=0.015. Changes in the difference between resting and post exercise Edt/RR also varied between groups: -53+/-137, -28+/-118, and 35+/-101 ms, respectively, P=0.029. No differences in E/A indices were noted. Resting atrioventricular plane displacement improved in the combined ramipril groups vs the placebo group: 0.2+/-0.8 vs -0.2+/-1.3 mm, P<0.05.Conclusion Six months ramipril treatment in patients with stable ischaemic heart disease and preserved left ventricular systolic function improved resting left ventricular function and reduced the exercise induced diastolic filling abnormalities usually seen in these patients.

H-2Dd engagement of Ly49A leads directly to Ly49A phosphorylation and recruitment of SHP1.

We have used a number of in vitro and in vivo techniques to identify the molecules that can bind to the cytoplasmic tail of the Ly49A receptor. Affinity chromatography using peptides corresponding to the N-terminal 18 amino acids of Ly49A allowed the recovery of a number of proteins that bound preferentially to the tyrosine-phosphorylated peptide, including SH2-containing phosphatase-1 (SHP1) and the SH2-containing inositol 5' phosphatase (SHIP). In another approach, using the entire cytoplasmic domain of the Ly49A receptor, we found that SHP2 also interacted with the tyrosine-phosphorylated form of the Ly49A cytoplasmic tail. Using BIACORE(R)2000 analysis, we determined that both SHP1 and SHP2 bound to the tyrosine-phosphorylated cytoplasmic tail of Ly49A with affinities in the nanomolar range, whilst SHIP showed no binding. Mutation of tyrosine-36 to phenylalanine did not significantly affect the affinities of these proteins for the tyrosine-phosphorylated cytoplasmic tail of Ly49A. In addition, using a whole-cell system with T-cell lymphoma cell lines that expressed the Ly49A receptor or its H-2Dd ligand, we determined that engagement of Ly49A by its major histocompatibility complex (MHC) ligand leads to tyrosine-phosphorylation events and recruitment of SHP1. Recruitment of SHP1 was rapid and transient, reaching a maximum after 5 min. These data suggest that mechanisms for the inhibitory signal are generated following receptor engagement. They also provide direct evidence that ligand engagement of the Ly49A receptor is responsible for recruitment of downstream signalling molecules.

Use of elaborative encoding to facilitate verbal learning after adolescent traumatic brain injury.

OBJECTIVE: To investigate the effectiveness of elaborative encoding in learning and remembering word definitions after traumatic brain injury (TBI). DESIGN: Two case studies. SETTING: University outpatient clinic. PARTICIPANTS: Two adolescents with severe memory impairments after TBI who needed specific vocabulary for school. INTERVENTIONS: A series of individual speech-language therapy sessions incorporating clinician- and subject-generated strategies to facilitate elaborative encoding. Target words were based on school requirements and pretreatment test results and were assigned randomly to treatment or control groups. MAIN OUTCOME MEASURE: Accuracy of free-recalled definitions at the conclusion of therapy and after 1 month with no therapy. RESULTS: Significant improvement in expressed word knowledge at the conclusion of therapy, with improvement on treated words maintained at 1 month for both subjects. CONCLUSIONS: Elaborative encoding was an effective tool for teaching specific information required for school. Patterns of response differed substantially from those of normally developing children. Generalization to classroom use was planned for and should be measured in future research.

Identification of a novel insertion element, IS1548, in group B streptococci, predominantly in strains causing endocarditis.

Hyaluronidase has been postulated to be a virulence factor in group B streptococci (GBS). No hyaluronidase activity was found in 15 of 50 GBS isolates from adults studied. Most of these hyaluronidase-negative strains belonged to serotype III. In strains lacking hyaluronidase activity, an insertion of 1317 nucleotides was found in the hyaluronidase gene. The fragment was cloned and sequenced and found to have characteristics of a novel insertion sequence, designated IS1548. As well as in GBS serotype III, this sequence was found in 3 of 6 serotype II isolates and in all 10 group A streptococcal strains (GAS) tested. Homologies were found with repeated sequences in Streptococcus pneumoniae and with H repeats in Escherichia coli. All GBS strains harboring IS1548 and some GAS strains had one copy of IS1548 located downstream of the C5a peptidase gene. IS1548 was present in 9 of 13 GBS isolates from blood in endocarditis patients and in 3 of 22 vaginally colonizing strains.

Early complications after anterior dislocation of the shoulder in patients over 40 years. An ultrasonographic and electromyographic study.

The rate of complications after anterior dislocation of the shoulder was evaluated in 65 patients aged over 40 years. 36 of 55 cases had electromyographically verified axillary nerve or brachial plexus injury. Rotator-cuff lesion was seen in 24 of the 63 sonographically examined cases. At follow-up in a telephone interview on average 3 years after the injury, 27 of the 57 cases had complaints from their shoulder. The incidence of initial nerve and/or cuff lesions was higher in those with persisting symptoms at follow-up.

Effect of ozone on metabolic activities of rat hepatocytes and mouse peritoneal macrophage.

Peritoneal macrophage from mice and isolated hepatocytes from rats were exposed to ozone. Ozone dosages were expressed as 0-5 nmol/10(6) cells. Measurements were made of viability, glucose transport, glutathione, glyceraldehyde-3-phosphate dehydrogenase, Mg-ATPase, Na/K-ATPase, and lipid synthesis. The most sensitive parameter was glyceraldehyde-3-phosphate dehydrogenase in the peritoneal macrophage. In hepatocytes both lipid synthesis and glyceraldehyde-3-phosphate dehydrogenase were sensitive to ozone. Effects on viability, glucose transport, Mg-ATPase, and Na/K-ATPase were small to negligible in both cell types.

Do muscle fibre size and fibre angulation correlate in pennated human muscles?

Several studies have reported estimations of the total number of fibres in a muscle, e.g. before and after training or before and after inactivity. In those investigations a combination of computed tomographic estimations of muscle size and morphological studies of fibre size has most often been used. There have been doubts about the reliability of those studies on pennate muscles, since changes in muscle fibre size have been said to alter fibre angulation and thus the number of fibres that will cross a section. If such an alteration in fibre angulation takes place with an increase in fibre size, there ought to be some correlation between fibre size and fibre angulation. The present study was designed to test whether repetitive estimations of muscle fibre angulation could be performed in vivo and if any such correlation could be found between fibre size and fibre angulation. A group of 15 women volunteered to take part in the study. Repeated ultrasonographic recordings were made on five subjects on 3 consecutive days to test the repeatability of ultrasonographic measurement of fibre angulation. Both muscle morphological analyses and ultrasonographic measurements of fibre angulation were performed on the other 10 subjects. Ultrasonographic measurement of fibre angulation was found to be reproducible since no variation between measurements made on different days was found. When trying to correlate muscle fibre size to the muscle fibre angulation, measured ultrasonographically, no significant correlation was found.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacterially expressed nucleoprotein of infectious hematopoietic necrosis virus augments protective immunity induced by the glycoprotein vaccine in fish.

The ribonucleoprotein gene of infectious hematopoietic necrosis virus (IHNV) has been expressed in Escherichia coli as a trpE fusion protein. This viral protein does not induce protective immunity to lethal IHNV infection in fish, and virus-neutralizing antibodies do not react with this viral protein. However, when it was administered with a bacterial lysate containing a region of the IHNV glycoprotein, there was enhanced resistance in immunized fish to lethal virus infection.

Hepatic portal vein gas following endoscopic retrograde cholangiography with sphincterotomy. Case report.

In a 60-year-old woman, endoscopic retrograde choledochography with sphincterotomy was followed by appearance of gas in the portal venous system. Venous bleeding was seen immediately after completion of sphincterotomy. The patient recovered well. Even in the absence of duodenal perforation, sphincterotomy may be complicated by hepatic portal venous gas.

Painful testicular lithiasis.

Testicular pain both acute and chronic is quite common and may result from many different diseases located both in and outside of the testis. Diffuse testicular microlithiasis is a rarely encountered problem in urology and up to now a unique sonographic appearance. We here report a case with combination of both signs and give a short review of the literature.