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S Fernando

Publications and source records attributed to S Fernando.

At least 19 recordsLinked to original sources
PubMed1998

A high-resolution microsatellite map of the mouse genome.

The European Collaborative Interspecific Backcross (EUCIB) resource was constructed for the purposes of high-resolution genetic mapping of the mouse genome (). The large Mus spretus/C57BL/6 backcross of 982 progeny has a genetic resolution of 0.3 cM at the 95% confidence level ( approximately 500 kb in the mouse genome). We have used the EUCIB mapping resource to develop a genome-wide high-resolution genetic map incorporating 3368 microsatellites. The microsatellites are distributed among 2302 genetically separated bins with 1.46 markers per bin on average. Average bin separation is 0.61 cM. This high-resolution genetic map will aid the construction of a robust physical map of the mouse genome.

Animals↗
PubMed1997

High-throughput microsatellite analysis using fluorescent dUTPs for high-resolution genetic mapping of the mouse genome.

The use of fluorescent end-labeled primers has proved successful for rapid, semiautomated genotyping of microsatellite loci. However, custom synthesis is expensive and costs can be prohibitive when a wide range of markers is to be analyzed for only a few genotypings. This particularly applies to high-resolution genetic mapping in the mouse either in the construction of global maps or in the production of local high-resolution genetic maps for positional cloning. We demonstrate here the use of fluorescent dUTPs for cost-effective, high-throughput microsatellite genotyping in the mouse. This alternative to the use of fluorescent end-labeled primers for semiautomated genotyping is potentially applicable to the construction of linkage maps in other species.

Animals↗
PubMed1995

AM630, a competitive cannabinoid receptor antagonist.

AM630 (iodopravadoline), a novel aminoalkylindole, has been found to attenuate the ability of a number of cannabinoids to inhibit electrically-evoked twitches of the mouse isolated vas deferens. It did not block the inhibitory effects of morphine or clonidine on the twitch response. AM630 behaved as a competitive antagonist of CP 55,940, WIN 55,212-2, anandamide and (R)-(+)-arachidonyl-1'-hydroxy-2'-propylamide (AM356), producing rightward shifts in the log concentration response curves of these cannabinoid receptor agonists that were concentration-dependent, essentially parallel and not accompanied by any decrease in the size of maximal response. AM630 also produced concentration-dependent, parallel rightward shifts in the log concentration-response curve of delta 9-THC. However, these shifts were accompanied by a decrease in the maximal response. AM630 was markedly more potent as an antagonist of delta 9-THC and CP 55,940 (Kd = 14.0 and 17.3 nM respectively) than as an antagonist of WIN 55,212-2, AM356 or anandamide (Kd = 36.5, 85.9 and 278.8 nM respectively). These differences in dissociation constant imply that the mouse vas deferens may contain more than one type of cannabinoid receptor. The data also indicate that the receptors for which AM630 has the highest affinity may not be CB1 cannabinoid receptors as the CB1 selective antagonist, SR141716A, is known to be equally potent in attenuating the inhibitory effects of CP 55,940 and anandamide on the twitch response of the mouse vas deferens.

Animals↗
PubMed1995

The detection of HIV-1 proviral DNA by PCR in clotted blood specimens.

Six hundred and ninety-two specimens, each consisting of a suspension of the residual free cells in samples of clotted blood (but not the clots themselves) from 680 patients at high risk for exposure to human immunodeficiency virus (HIV), were tested by a nested polymerase chain reaction (PCR) procedure which had been optimized to give a sensitivity of detection of one copy of HIV-1 proviral plasmid DNA, and the results were compared to those of testing for antibody to HIV on the same specimens. Fifty-one of the specimens were positive for antibody to HIV and 49 of these were also positive by the PCR; the two samples which gave discordant results were found to be PCR-positive when the test was repeated on DNA extracted from the clots themselves. Two specimens were found to be negative for antibody to HIV but were positive by the PCR (53 positive specimens in all). Direct sequencing of the PCR DNA products confirmed their specificity in all cases and demonstrated that no two patients gave the same predicted amino acid sequence for the V3 loop region. The sequences revealed both European/North American and African motifs at the crown of the V3 loop thus indicating a diversity of HIV strains in the SW Thames Region of South London. The results show that the confirmatory PCR for HIV-1 can be carried out efficiently on the same clotted blood specimens as used for routine HIV serology on patients undergoing diagnostic evaluation.

Africa↗
PubMed1995

Smoking in hotels: prevalence, and opinions about restrictions.

Exposure to high levels of environmental tobacco smoke can occur in hotels. Controversy exists about smoking regulation on licensed premises. This survey of 138 people attending one of three Newcastle hotels during 1993 found that 57 per cent of respondents were nonsmokers. Fifty-eight per cent (95 per cent confidence interval (CI) 50 to 66 per cent) of respondents in these hotels believed their health was being adversely affected by other people's smoke in the hotel. Seventy per cent (CI 62 to 78 per cent), including half the smokers, were in favour of restriction of smoking in the hotels. Most preferred the establishment of smoke-free areas to the introduction of total smoking bans in hotels. The failure of hotels to regulate smoking suggests that a legislative approach is required. The case for legislation would be strengthened by a larger study elsewhere in Australia.

Adult↗
PubMed1994

Association of cytomegalovirus infection with post-transplantation cardiac rejection as studied using the polymerase chain reaction.

The relationship between cytomegalovirus (CMV) infection and cardiac allograft rejection is controversial, some authors reporting a significant association, others not, on the basis of the results of conventional virological diagnosis by culture or serology. This problem was reinvestigated in 88 patients using a semi-quantitative nest polymerase chain reaction (PCR) procedure for detecting CMV DNA in endomyocardial biopsy specimens. Significantly more positive biopsies were obtained from patients with moderate (grade 2; P = 0.02) or severe (grade 3a-4; P = 0.03) rejection than with no or mild (grade 0-1b) rejection, whereas there was no significant association between rejection and CMV as diagnosed by virus isolation from urine, throat or blood, or by the detection of CMV-IgM. PCR-positive biopsies originated most frequently from CMV-antibody positive recipients (R+) of hearts from seropositive donors (D+), in association with moderate or severe rejection rather than with mild or no rejection The detection of CMV in the heart thus seemed to be related more to R+D+ serological status than to severity of rejection, that is, to circumstances that favoured co-infection with strains of CMV from both donor and recipient. Studies on sequential biopsy specimens from selected patients also provided evidence that CMV infection and rejection were not always related events. The PCR was able to differentiate latent from active CMV infection; moreover, some seronegative individuals gave repeatedly positive biopsies, thereby supporting the work of others that some patients undergo CMV infection without mounting a detectable antibody response.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Differences in nigral neuron number and sensitivity to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine in C57/bl and CD-1 mice.

The present study demonstrates that the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) causes significantly greater reductions in striatal dopamine levels in C57/bl mice than in CD-1 mice, thus confirming a greater sensitivity of the C57/bl mice to MPTP. To determine the possible reasons for this difference in MPTP sensitivity between these two mouse strains, we have compared both the organization and the number of substantia nigra (SN) neurons, the primary target of MPTP, in C57/bl and in CD-1 mice using immunostaining for tyrosine hydroxylase (TH) and calbindin-D28k (calbindin). In saline-injected animals, there is a significantly lower number of SN TH-positive and calbindin-positive neurons in C57/bl than CD-1 mice; no significant differences in the numbers of these neurons are found in the ventral tegmental area between the two strains. In MPTP-injected animals, the reductions in SN TH-positive neurons are significantly greater in C57/bl than in CD-1 mice. In contrast, MPTP does not cause any significant changes in the numbers of SN calbindin-positive neurons in either strain. The present study shows that C57/bl mice which have fewer SN TH-positive neurons are more sensitive to MPTP-induced toxicity than CD-1 mice. This observation suggests a possible inverse relationship between SN TH-positive neuron number and MPTP sensitivity. If correct, this hypothesis may be of major importance for Parkinson's disease since it is suggested that individuals at risk of developing this neurodegenerative disorder may have lower numbers of SN TH-positive neurons to start with. The present study also shows that SN calbindin-positive neurons are spared following MPTP administration. However, the observed difference in SN calbindin-positive neuron numbers does not account for the differential sensitivity to MPTP between these two mouse strains.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1994

Quantification of cytomegalovirus DNA in blood specimens from bone marrow transplant recipients by the polymerase chain reaction.

A nested PCR system for cytomegalovirus (CMV) DNA in blood specimens from bone marrow transplant recipients is described, in which the biotinylated tritium-labelled product from the second round of PCR is quantified using streptavidin-coated fluorometric Scintillation Proximity Assay (SPA) beads (Amersham, UK). This assay has been compared with a PCR procedure based on limiting-dilution, in which the end-point is determined visually following electrophoresis in agarose gel. The two systems were shown to be equivalent in sensitivity and specificity on testing stored serial blood samples from six CMV antibody-positive allogeneic bone marrow transplant patients who developed viraemia as detected by conventional methods of virus isolation in tissue culture.

Base Sequence↗
PubMed1993

Lymphocyte responses and virus excretion as risk factors for intrauterine infection with cytomegalovirus.

Serological screening of pregnant women in this and a previous study identified 28 cases of primary infection with cytomegalovirus, 7 (25%) of whom transmitted the infection to their fetuses. Risk factors for intrauterine infection were: 1) age less than 20 years, 2) Caucasian rather than non-Caucasian race, 3) a weak response to cytomegalovirus antigen in the lymphocyte transformation test, and 4) the excretion of cytomegalovirus in the urine. The greatest risk was when a weak lymphoproliferative response was detected in combination with a positive result for virus isolation, in which case the chance of fetal infection was 83%. Despite these associations, there was one important anomalous result of a woman who demonstrated a strong lymphocyte response during pregnancy and a negative result for virus isolation, but who gave birth to an infected baby who developed unilateral hearing loss.

Adult↗
PubMed1993

A randomised double blind comparative study of low level laser therapy following surgical extraction of lower third molar teeth.

A randomised, double blind comparative study was undertaken to assess the efficacy of low level laser therapy in the reduction of postoperative pain and swelling in patients undergoing the extraction of bilaterally impacted mandibular third molar teeth. Healing of the sockets was also compared after 1 week. A group of 64 patients had one randomly-selected operation side treated with a semi-conductor laser and the other side with an apparently identical but non-operating model. Complete data were obtained from 52 of the 64 patients. The results showed that there was no evidence of a difference in pain and swelling on the third day after operation between laser and placebo sides. There was no difference between the two sides when they were assessed for healing 7 days after surgery.

Adolescent↗
PubMed1991

Racial stereotypes.

Explore the source record for details and available documents.

Black or African American↗