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S Lindsay

Publications and source records attributed to S Lindsay.

At least 19 recordsLinked to original sources
PubMed1998

Utrophin mRNA expression in muscle is not restricted to the neuromuscular junction.

Utrophin is normally present exclusively in synaptic regions of skeletal muscle fibers, although it is expressed extrasynaptically in certain pathological situations, where it has been proposed to compensate for the absence of dystrophin in Duchenne muscular dystrophy patients and mdx mice. Recently there have been conflicting reports regarding the preferential expression of utrophin mRNA at the neuromuscular junction. Using in situ hybridization with RNA probes, we show a clear accumulation of autoradiographic labeling at more than 90% of neuromuscular junctions (identified by histochemical demonstration of cholinesterase activity). The intensity of this labeling is proportional to the number of junctional myonuclei in the section. Some clusters of labeling were found associated with nonmuscle nuclei (e.g., blood vessels, nerves), where utrophin is present. In addition, labeling for utrophin mRNA was associated with about 25% of extrajunctional myonuclei, where the protein is not present. The mean labeling per nucleus at junctional myonuclei was at least 10 times greater than at extrajunctional myonuclei. We discuss the possible regulatory mechanisms involved in the heterogeneous expression of utrophin mRNA in skeletal muscle.

Amino Acid Sequence↗
PubMed1998

An improved method for the simultaneous demonstration of mRNA and esterase activity at the human neuromuscular junction.

The aim of this study was to develop a simple means of studying the distribution of mRNA coding for post-synaptic proteins at the human neuromuscular junction. A reliable method by which to identify the junctions in tissue sections after in situ hybridization was essential. A method is described for combining the histochemical demonstration of esterase activity at the neuromuscular junction with autoradiographic localization of mRNA by in situ hybridization in the same cryostat section of skeletal muscle. The indigogenic esterase method of Strum and Hall-Craggs (1982) was modified in such a way that it is able to survive the multiple steps involved in in situ hybridization and autoradiography. The protocol is simple and reproducible and has been used successfully on sections of both rat and human skeletal muscle. To demonstrate the method, sections were reacted to reveal esterase activity and were then processed for in situ hybridization using a 35S-labelled probe specific for the epsilon-subunit of the acetylcholine receptor. The reaction product was retained after the lengthy in situ hybridization and autoradiographic procedures. To our knowledge, this is the first demonstration of acetylcholine receptor mRNA by in situ hybridization at human neuromuscular junctions.

Animals↗
PubMed1998

A novel mammalian wnt gene, WNT8B, shows brain-restricted expression in early development, with sharply delimited expression boundaries in the developing forebrain.

Our current knowledge of mammalian forebrain development is meagre. The comparatively few relevant anatomical landmarks are, however, being supplemented by gene expression studies which are able to identify subsets of anatomical structures. We previously described cloning, subchromosomal localization and preliminary structural characterization of the human WNT8B gene, the first mammalian Wnt8b gene to be reported. Wnt genes encode intercellular signalling molecules which play a variety of critical roles in early development, including, in several cases, a presumed role in brain development. In the current report we present the full-length cDNA sequence and genomic organization of the human Wnt8b gene and report studies of expression of the Wnt8b gene in human and mouse embryos. The human and mouse expression patterns appeared identical and were restricted to the developing brain, with the great majority of expression being found in the developing forebrain. In the latter case expression was confined to the germinative neuroepithelium of three sharply delimited regions: the dorsomedial wall of the telencephalic ventricles (which includes the developing hippocampus), a discrete region of the dorsal thalamus and the mammillary and retromammillary regions of the posterior hypothalamus. Expression in the developing hippocampus may suggest a role for WNT8B in patterning of this region and subchromosomal localization of the human gene to 10q24 may suggest it as a candidate gene for partial epilepsy in families where the disease has been linked to markers in this region.

Amino Acid Sequence↗
PubMed1998

Utrophin mRNA Expression in Muscle Is Not Restricted to the Neuromuscular Junction.

Utrophin is normally present exclusively in synaptic regions of skeletal muscle fibers, although it is expressed extrasynaptically in certain pathological situations, where it has been proposed to compensate for the absence of dystrophin in Duchenne muscular dystrophy patients and mdx mice. Recently there have been conflicting reports regarding the preferential expression of utrophin mRNA at the neuromuscular junction. Using in situ hybridization with RNA probes, we show a clear accumulation of autoradiographic labeling at more than 90% of neuromuscular junctions (identified by histochemical demonstration of cholinesterase activity). The intensity of this labeling is proportional to the number of junctional myonuclei in the section. Some clusters of labeling were found associated with nonmuscle nuclei (e.g., blood vessels, nerves), where utrophin is present. In addition, labeling for utrophin mRNA was associated with about 25% of extrajunctional myonuclei, where the protein is not present. The mean labeling per nucleus at junctional myonuclei was at least 10 times greater than at extrajunctional myonuclei. We discuss the possible regulatory mechanisms involved in the heterogeneous expression of utrophin mRNA in skeletal muscle. Copyright 1998 Academic Press.

Journal Article↗
PubMed1997

Isolation of a full-length human WNT7A gene implicated in limb development and cell transformation, and mapping to chromosome 3p25.

The Wnt gene family has a role in development as well as tumourigenesis. One mouse member, Wnt7a, is vital for limb development in vivo and also possesses transforming ability in vitro. This study reports the isolation of a full length of human homologue of mouse Wnt7a gene by library screening. Yeast artificial chromosome-fluorescence in situ hybridisation (YAC-FISH) mapped the WNT7A gene to chromosome 3p25. Human WNT7A had an ORF encoding a deduced protein of 349 aa that exhibited 97% and 92% identity to mouse Wnt7a at the aa and nucleic acid levels, respectively. It possessed the 22 conserved cysteine residues and 3 more at the amino terminus, and a putative poly A tail. This is the fifth human WNT gene in which a complete cDNA sequence had been determined.

Amino Acid Sequence↗
PubMed1997

A novel human Wnt gene, WNT10B, maps to 12q13 and is expressed in human breast carcinomas.

Several members of the Wnt gene family have been shown to cause mammary tumors in mouse. Using degenerate primer polymerase chain reaction (PCR) on human genomic DNA, and specific PCR of cDNA libraries, we have isolated a WNT gene which has not previously been described in human. The gene is the human homologue of mouse Wnt10b, recently shown to be one of the oncogenes cooperating with FGF3 in the development of mouse mammary tumour virus (MMTV) induced mouse mammary carcinomas. The human WNT10B sequence was 88% and 95% identical to the murine gene at nucleotide and amino acid levels, respectively. YAC FISH mapping localises the gene to 12q13, a chromosomal region frequently rearranged in human tumours and also containing the WNT1 gene. In normal and benign proliferations of human breast tissue, WNT10B expression was not detected by ribonuclease protection assays but was found at low levels in RT-PCR experiments. In contrast, using both methods, WNT10B expression was found to be elevated in 3 of 50 primary breast carcinomas. Southern blot analysis of the carcinoma expressing the highest levels of WNT10B showed no amplification or rearrangement of the gene. The WNT10B gene was also expressed in some cancer and non cancerous breast cell lines. These findings suggest that the WNT10B gene may be involved in human breast cancer, and show that there is differential expression of the WNT10B gene in benign and malignant disease.

Amino Acid Sequence↗
PubMed1997

Feasibility and applicability of coronary stent implantation with the direct brachial approach: results of a single-center study.

Implantation of stents in selected patients improves outcome after coronary angioplasty. Newer antiplatelet regimes limit access site complications associated with stenting by the percutaneous femoral approach, but a substantial proportion of patients will require anticoagulant therapy for concomitant disease or will have peripheral vascular disease that prevents access from the leg. We investigated procedural success rates and outcome in consecutive patients undergoing elective stent implantation in our institution. In 73 patients who were receiving anticoagulation therapy and were stented by a direct approach to the left brachial artery, 98.6% of stents were successfully deployed, with a major vascular access site complication rate of 1.4%. Equipment consumption, procedural success rate, and fluoroscopy time were similar in patients stented by the direct brachial or percutaneous femoral approach. Where the percutaneous femoral approach is precluded or patients are anticoagulated, stent procedures can be successfully performed by the direct brachial approach with a low rate of access site complications, even when large-caliber guiding catheters are required.

Adult↗
PubMed1997

Chronic low back pain: predictions of pain and relationship to anxiety and avoidance.

The present study examined the discrepancy between prediction and experience of pain in 20 chronic low back pain (CLBP) patients undertaking a series of standard physical exercises. Subjects gave ratings of predicted pain and anxiety before each exercise and a rating of the pain experienced during the exercise. Contrary to prediction, the majority of CLBP patients predicted less pain than they subsequently experienced. Moreover, multiple regression analysis showed that, in these patients, the greater the discrepancy between predicted and experienced pain the greater the increase in pain predicted for the subsequent exercise. Anxiety was greater the higher the level of pain predicted, although it was not significantly related to the amount of pain experienced on the previous exercise or to the discrepancy between predicted and experienced pain. However, the discrepancy between predicted and experienced pain was found to be related to subsequent physical performance whereas the other variables were not; the more that pain exceeded expectations on the first exercise the less patients performed on the subsequent exercises. The results of this study are compared with those of previous studies and the implications of the findings to the maintenance of CLBP are discussed.

Adult↗
PubMed1997

Process and outcome in a hostel outreach program for homeless clients with severe mental illness.

A longitudinal study followed 55 homeless and severely mentally ill clients of a hostel outreach program to assess outcomes and their relationship to program elements. Results at 18-month follow-up indicated that, despite chronic histories of transiency and shelter use, housing stability had been achieved, and that initial gains in social functioning and symptom reduction had been increased. Development of a strong working alliance proved a key program element in the findings.

Adult↗
PubMed1997

Large scale deletions in the GPC3 gene may account for a minority of cases of Simpson-Golabi-Behmel syndrome.

AIMS OF THE STUDY: To identify the proportion and type of deletions present in the glypican 3 (GPC3) gene in a group of patients with Simpson-Golabi-Behmel syndrome (SGBS). SUBJECTS AND METHODS: PCR analysis using primer pairs which amplify fragments from each of the eight exons of the GPC3 gene was carried out in a series of 18 families with SGBS (approximately half of reported cases). RESULTS: Deletions were detected in only five families (one reported previously). We found deletions in all exons of the gene except exon 3. CONCLUSIONS: Our results suggest that large scale deletions may be less common in SGBS than was originally thought. One patient, with an exon 4 and 5 deletion, lacked the characteristic facial dysmorphic features. This raises the possibility of involvement of GPC3 gene defects in a wider range of overgrowth disorders.

Abnormalities, Multiple↗
PubMed1996

Isolation and characterization of WNT8B, a novel human Wnt gene that maps to 10q24.

Wnt genes encode intercellular signalling molecules that play important roles in key processes of embryonic development such as mesoderm induction, specification of the embryonic axis, and patterning of the central nervous system, spinal cord, and limb. Multiple such genes are known to exist in each of several species that have been investigated, and they have been classified into various groups and subgroups on the basis of high sequence homology and common expression patterns. The vertebrate Wnt8 subfamily includes genes from Xenopus, zebrafish, and chicken, but, to date, no mammalian homologues have been described. We now report cloning and characterization of a novel human member of this family that we have termed WNT8B on the basis of the very high sequence similarity of the inferred protein to those encoded by the Xenopus and zebrafish Wnt8b genes. PCR typing of a human monochromosomal hybrid cell panel mapped the gene to chromosome 10, and FISH mapping provided a subchromosomal location at 10q24. Northern blotting and RT-PCR assays indicated that the WNT8B gene is expressed in several human tissues during fetal and adult stages.

Adult↗
PubMed1996

CAC--the neglected repeat.

It is becoming increasingly clear that repetitive DNA is of biological significance as well as experimental importance. Here we review the information available about one type of repetitive DNA, the trinucleotide repeat (CAC)n, and briefly compare it with other trinucleotide repeats. Although much work has been done in analysing DNA fingerprinting patterns produced using the synthetic oligonucleotide (CAC)5 as a probe, there is relatively little information about individual (CAC)n-containing sequences and their abundance, organisation and distribution in mammalian DNA. From the data that is available, it is clear that there are at least two areas that should repay further study: (1) the organisation and generation of long sequences that contain (CAC)n motifs as part of a larger repeating unit (minisatellites) and (2) the distribution of small (CAC)n sequences (microsatellites), in particular their relationship to genes.

Base Sequence↗
PubMed1996

Extraperitoneal laparoscopic caliceal diverticulectomy.

Three women with symptomatic stone-containing caliceal diverticula in the right kidney were treated by extraperitoneal laparoscopic diverticulectomy. The diverticula measured 31 x 21 mm, 15 x 12 mm, and 12 x 9 mm, with the calculi measuring 10 x 8 mm, 5 x 4 mm, and 6 x 6 mm, respectively. The site of the diverticulum was identified by the presence of a depression on the surface of the kidney. The diverticulum was marsupialized, the lining fulgurated, and in the second and third patients, a flap of Gerota's fascia and perirenal fat inserted. The mean operating time was 127 minutes. The mean postoperative analgesic requirement was six doses of pethidine (meperidine). The median time to drainage tube removal was 3 days, and the median time to discharge after surgery was 4 days. Complications were minimal. On follow-up, all patients were stone free and asymptomatic. The first patient had a slight recurrence of the diverticulum, measuring 15 x 7 mm. Laparoscopic caliceal diverticulectomy has been successful in three patients.

Adult↗
PubMed1996

PPM-X: a new X-linked mental retardation syndrome with psychosis, pyramidal signs, and macroorchidism maps to Xq28.

We report a three-generation family manifesting a previously undescribed X-linked mental retardation syndrome. Four of the six moderately retarded males have had episodes of manic-depressive psychosis. The phenotype also includes pyramidal signs, Parkinsonian features, and macroorchidism, but there are no characteristic dysmorphic facial features. Affected males do not show fragile sites at distal Xq on cytogenetic analysis, nor do they have expansions of the CGG repeats at the FRAXA, FRAXE, or FRAXF loci. Linkage analyses were undertaken, and a maximal LOD score of 3.311 at theta = .0 was observed with the microsatellite marker DXS1123 in Xq28. A recombination was detected in one of the affected males with DXS1691 (Xq28), which gives the proximal boundary of the localization. No distal recombination has been detected at any of the loci tested.

Adolescent↗
PubMed1996

Adolescents' perceptions of the role of part-time work.

In contrast to the U.S., research on child employment in Britain has been relatively rare. This paper reports the findings from a study in which 1,220 students, 12-16 years of age, in two comparable schools in England and Scotland completed questionnaires on their employment. While the nature and extent of employment were assessed by means of a questionnaire, a sub-sample of students (N = 56) participated in interviews to provide more detailed information on their experience of employment. Results indicate that Green (1990) may have been overly optimistic in arguing against the negative stereotype of the student worker, at least as far as the United Kingdom is concerned. Although students may be able to control whether they work, the interview data indicate that they have little control over their work environment and do not always view employment in a positive light.

Adolescent↗
PubMed1995

Crossover analysis in a British family suggests that Coffin-Lowry syndrome maps to a 3.4-cM interval in Xp22.

Coffin-Lowry syndrome (CLS; MIM 303600) in an uncommon X-linked disorder causing mental retardation and skeletal abnormalities. Most recently it was mapped to a 5.6-centimorgan (cM) region of Xp22, flanked distally by AFM291wf5 and proximally by DXS1052 [Biancalana et al., 1994: Genomics 22:617-625]. We present information which supports this localization and further narrows the region to approximately 3.4 cM. A recombination in a carrier from a British family mean that DXS365 is the closest proximal flanking marker identified to date for the region thought to contain the CLS gene. This information reduces the region of interest by approximately 2.2 cM, a significant decrease in terms of the scale of effort which will be required to isolate and analyze candidate genes.

Adolescent↗
PubMed1995

Reducing anxiety in new dental patients by means of leaflets.

Fifty adults, consecutive attenders at a dentist who was new to them, were selected. They completed the Spielberger State Anxiety Inventory before and after they had read one of two different leaflets in the waiting room. One, the informative leaflet, included information about pain control and stop signals. A comparison leaflet did not include this information but acknowledged, sympathetically, that many people are nervous of dental treatment. The leaflet also provided some explanations for that fear. Both leaflets were designed, according to published evidence, to be easily read and understood. The layout drew attention to the most important points. State Anxiety decreased significantly only in the patients who read the informative leaflet (P < 0.01). This occurred before the patients met their new dentist. Those patients given the informative leaflet rated it as much more helpful than those given the comparison leaflet (P = 0.007).

Adolescent↗