Candidate DNA replication initiation regions at human trinucleotide repeat disease loci

The positions of DNA replication initiation regions (IRs) at three human trinucleotide repeat (TNR) disease loci were examined in order to characterize the role played by IRs in explaining the known locus-specific variation in TNR instability levels. Using three different normal cell lines, candidate IRs were identified at the HD, SCA-7 and SBMA loci. At each locus the IR is less than 3.6 kb from the CAG/CTG repeat tract. Preliminary studies with a cell line homozygous for an HD disease mutation indicated no change in the position of the candidate IR in spite of the mutation. Comparison with experimental results from model systems suggests that a complex relationship may exist between instability and the proximity and/or orientation of the repeats with respect to an IR.     

Correlation of testicular sperm extraction with morphological, biophysical and endocrine profiles in men with azoospermia due to primary gonadal failure

To identify the predictive factors for testicular sperm extraction (TESE) and to understand the pathology associated with TESE, we carried out a prospective study in 40 consecutive men with azoospermia due to primary gonadal failure. The main outcome measure was the retrieval of at least one testicular spermatozoon. Endocrine and biophysical profiles, testicular histology, Johnsen score and testicular spermatids were used as predictors of sperm extraction. Spermatogenesis was quantified with the Johnsen score. A variable pattern of spermatogenesis was common, being present in 20 (50%) patients. Visualisation of testicular spermatids on testicular histology showed a strong association with TESE (P < 0.0001). Statistically significant differences were detected in plasma follicle stimulating hormone (FSH) and testicular volume between patients who had hypospermatogenesis and Sertoli cell-only or maturation arrest. There were no significant differences in Johnsen score, biophysical and endocrine profiles between the groups with successful and failed TESE. However, a statistically significant trend occurred with changes in histological pattern [chi2 for trend, P = 0.001; Pearson's coefficient (r) = 0.6], Johnsen score (P = 0.022; r = 0.5), testicular volume (P = 0.01; r = 0.5) and plasma FSH concentrations (P = 0.044; r = 0.4), albeit to a limited degree. Difference in the interpretation of histological patterns with different assessors was observed. The type of occupation or risk factors for azoospermia showed no association with testicular pathology or TESE. Variable histological patterns in different tubules in the same individual may explain the poor correlation of TESE with endocrine and biophysical profiles, Johnsen score and histological pattern. Differences in the amount of tissue used for TESE and histopathology, and misinterpretation of testicular histology rather than failure to quantify spermatogenesis may explain the poor correlation between histological patterns and TESE. Testicular spermatids predicted TESE. However, considerable overlap in values means that no single variable can provide a perfect discrimination between the groups with successful and failed TESE.      

Influence of ischaemia and reperfusion on cardiac signal transduction. G protein content, adenylyl cyclase activity, cyclic AMP content, and forskolin and dibutyryl cyclic AMP-induced inotropy in the rat Langendorff heart

Summary— We investigated whether post-receptor alterations contribute to the diminished β-adrenergic inotropic effects in the rat Langendorff heart following ischaemia (I) and reperfusion (R). We quantitated immunodetectable G_s and G_i protein α-subunit content, basal and stimulated adenylyl cyclase activity and cyclic AMP (cAMP) content in normoxic, ischaemic (30 min) and ischaemic reperfused (30 min) hearts. In addition, we measured the inotropic response of normoxic and reperfused Langendorff hearts to forskolin and dibutyryl cAMP (db-cAMP). Immunodetectable G_s and G_i α-subunits were unaltered by I or R. Basal adenylyl cyclase activity was decreased during I, but recovered during R. In membranes from normoxic hearts, isoprenaline, GTP, Gpp(NH)p, NaF, forskolin or Mn²⁺ enhanced adenylyl cyclase activity. This increase in activity was diminished in ischaemic hearts, but could be restored by R. cAMP content decreased time-dependently during I and did not recover by R, indicating ATP depletion. Forskolin and db-cAMP induced an inotropic response in normoxic hearts, which was virtually abolished after I and R. We conclude that adenylyl cyclase responsiveness is impaired during I. Since adenylyl cyclase responsiveness recovers during R, whereas inotropic responses to forskolin and db-cAMP are virtually absent in reperfused hearts, an additional mechanism downstream of cAMP formation appears to be defective during R, which prevents recovery of inotropic responses to hormonal stimulation.     

Three-phase radionuclide scintigraphy of the hand

Three-phase radionuclide scintigraphy of the hand was performed on 116 patients. Normal and abnormal patterns for radionuclide angiography, immediate post-injection blood-pool images, and delayed scans (3-4 hr.) were established. Of 80 patients with normal circulation, 61 (76%) had equal radial and ulnar artery flow bilaterally, while in 19 (24%) either the radial or ulnar artery was dominant. Abnormal studies were grouped into three categories: suspected vascular lesions (Group I), pain of uncertain etiology (Group II), and patients evaluated before and after reconstructive surgery (Group III). The diagnosis was correct in 89% of the patients in Group I (34/38), 89% of those in Group II (57/64), and all of those in Group III (14/14). Three-phase scintigraphy of the hand yields significant information about perfusion and bone metabolism.     

An item response analysis of the motor and behavioral subscales of the unified Huntington's disease rating scale in huntington disease gene expansion carriers

Although the Unified Huntington's Disease Rating Scale (UHDRS) is widely used in the assessment of Huntington disease (HD), the ability of individual items to discriminate individual differences in motor or behavioral manifestations has not been extensively studied in HD gene expansion carriers without a motor‐defined clinical diagnosis (ie, prodromal‐HD or prHD). To elucidate the relationship between scores on individual motor and behavioral UHDRS items and total score for each subscale, a nonparametric item response analysis was performed on retrospective data from 2 multicenter longitudinal studies. Motor and behavioral assessments were supplied for 737 prHD individuals with data from 2114 visits (PREDICT‐HD) and 686 HD individuals with data from 1482 visits (REGISTRY). Option characteristic curves were generated for UHDRS subscale items in relation to their subscale score. In prHD, overall severity of motor signs was low, and participants had scores of 2 or above on very few items. In HD, motor items that assessed ocular pursuit, saccade initiation, finger tapping, tandem walking, and to a lesser extent, saccade velocity, dysarthria, tongue protrusion, pronation/supination, Luria, bradykinesia, choreas, gait, and balance on the retropulsion test were found to discriminate individual differences across a broad range of motor severity. In prHD, depressed mood, anxiety, and irritable behavior demonstrated good discriminative properties. In HD, depressed mood demonstrated a good relationship with the overall behavioral score. These data suggest that at least some UHDRS items appear to have utility across a broad range of severity, although many items demonstrate problematic features. © 2011 Movement Disorder Society     

Peptide screening of cerebrospinal fluid in patients with glioblastoma multiforme

Aims

To apply modern mass spectrometry based technology to identify possible CSF peptide markers of glioblastoma multiforme (GBM).

Methods

Mass spectrometry based peptidomics^® technology enables a systematic and comprehensive screening of cerebrospinal fluid (CSF) with regard to its peptide composition. Differential Peptide Display^® (DPD) allows the identification of single marker peptides for a target disease. Using both, we analyzed CSF samples of 11 patients harbouring a glioblastoma multiforme in comparison to 13 normal controls.

Results

Four CSF peptides which significantly distinguished GBM from controls in all applied statistic tests could be identified out of more than 2000 detected CSF peptides. They were specific C-terminal fragments of alpha-1-antichymotrypsin, osteopontin, and transthyretin as well as a N-terminal residue of albumin. All molecules are constituents of normal CSF, but none has previously been reported to be significantly elevated in CSF of GBM patients.

Conclusion

The study showed that peptidomics technology is able to identify possible biomarkers of neoplastic CNS disease. It remains to be determined if the identified elevated CSF peptides are specific for GBM. With regard to GBM, however, the more important role of CSF peptide biomarkers than aiding initial diagnosis might be early recognition of disease recurrence or monitoring of efficacy of adjuvant therapy protocols.     

Improved immune reconstitution after allotransplantation of peripheral blood stem cells instead of bone marrow

Clinical studies are evaluating possible advantages of allogeneic peripheral blood stem cell transplantation (PBSCT) over bone marrow transplantation (BMT). We compared immune reconstitution after PBSCT (n = 20) and BMT (n = 20) in terms of lymphocyte subset counts and proliferative in vitro responses to mitogens and recall antigens (follow-up: 5 to 11 months posttransplant). Additionally, 10 PBSC harvests and 10 marrow harvests were analyzed for their composition of immunocompetent cells. Compared with BMT patients, PBSCT recipients had PB counts of naive (CD4+CD45RA+) and memory (CD4+CD45RO+) helper T cells and of B cells (CD19+) that were elevated (P < .003, P < .001, and P < .004, respectively) and proliferative responses to phytohemagglutinin (P < .0001), pokeweed mitogen (P < .02), Tetanus toxoid (P < .0005), and Candida (P < .004) that were increased. PBSCT recipients received a mean of 188 (range, 44 to 280) x 10(6) naive helper T cells and 169 (range, 18 to 296) x 10(5) memory helper T cells per kilogram; the corresponding numbers for BMT recipients were 11 (range, 4 to 24) and 10 (range, 1 to 22) x 10(5) cells per kilogram, respectively. The question of whether the documented improved in vitro immune competence after PBSCT is associated with a lower incidence of infectious complications in vivo still needs further study.     

Long-term Clinical Performance of Resin-Bonded Fixed Partial Dentures Placed in a Developing Country

Purpose This study assesses the clinical performance of 92 resin-bonded fixed partial dentures (FPDs) placed at four private practices in Karachi, Pakistan, between 1982 and 1991. Materials and Methods The distribution of the FPDs was 9 perforated, 45 electrolytically etched, and 38 silicoated. Twenty-five FPDs replaced anterior teeth and 67 replaced posterior teeth. There were 66 FPDs with single pontics and 26 with multiple pontics. The perforated designs used a restorative composite for cementation, whereas the electrolytically etched and silicoated designs used a composite luting cement. The observation periods for the perforated, electrolytically etched, and silicoated FPDs were 114,99, and 30 months respectively. Results During the evaluation period, 27 FPDs (29%) failed; of these, 4 were perforated, 18 were electrolytically etched, and 5 were silicoated. The mean (±SD) duration of the successful clinical service for all FPDs was 41 ± 26 months. The mean time to failure for the FPDs that did not survive was 35 ± 23 months. The silicoated FPDs tended to have early failure, as did the FPDs with multiple pontics and those in the mandibular arch. Anterior and posterior FPDs performed equally well. Conclusions These findings, in conjunction with those from Europe and North American, show that resin-bonded FPD technology is as successful in a developing country as in industrialized areas of the world.