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Biomedical subjects

D Moss

Publications and source records attributed to D Moss.

At least 19 recordsLinked to original sources
PubMed2004

Mid-IR synchrotron radiation for molecular specific detection in microchip-based analysis systems.

Microstructures constructed from SU-8 polymer and produced on CaF(2) base plates have been developed for microchip-based analysis systems used to perform FTIR spectroscopic detection using mid-IR synchrotron radiation. The high brilliance of the synchrotron source enables measurements at spot sizes at the diffraction limit of mid-IR radiation. This corresponds to a spatial resolution of a few micrometers (5-20 microm). These small measurement spots are useful for lab-on-a-chip devices, since their sizes are comparable to those of the structures usually used in these devices. Two different types of microchips are introduced here. The first chip was designed for time-resolved FTIR investigations of chemical reactions in solution. The second chip was designed for chip-based electrophoresis with IR detection on-chip. The results obtained prove the operational functionality of these chips, and indicate the potential of these new devices for further applications in (bio)analytical chemistry.

Journal Article↗
PubMed2003

An easily automated, closed-tube forensic DNA extraction procedure using a thermostable proteinase.

Most standard procedures for extracting DNA from forensic substrates involve manipulations that expose the sample to potential contamination and which reduce yields. Furthermore, most methods require centrifugation and/or solvent extraction steps that render them difficult to automate. We describe a simple closed-tube DNA extraction procedure using a proteinase from the thermophilic Bacillus species EA1 that produces good DNA yields from a wide range of forensic substrates. The reaction is controlled by a temperature shift regime programmed into a thermal cycler and so eliminates the need for solvent extraction or column purification. The new method is ideally suited to forensic samples where exposure to extraneous contaminating DNA must be avoided. In addition, The simplicity of the procedure makes it suitable for automation.

Autoanalysis↗
PubMed2003

Melatonin-secreting pineal gland: a novel tissue source for neural transplantation therapy in stroke.

Chronic systemic melatonin treatment attenuates abnormalities produced by occlusion of middle cerebral artery (MCA) in adult rats. Because the pineal gland secretes high levels of melatonin, we examined in the present study whether transplantation of pineal gland exerted similar protective effects in MCA-occluded adult rats. Animals underwent same-day MCA occlusion and either intrastriatal transplantation of pineal gland (harvested from 2-month-old rats) or vehicle infusion. Behavioral tests (from day of surgery to 3 days posttransplantation) revealed that transplanted stroke rats displayed significantly less motor asymmetrical behaviors than vehicle-infused stroke rats. Histological analysis at 3 days posttransplantation revealed that transplanted stroke rats had significantly smaller cerebral infarction than vehicle-infused rats. Additional experiments showed that pinealectomy affected transplantation outcome, in that transplantation of pineal gland only protected against stroke-induced deficits in stroke animals with intact pineal gland, but not in pinealectomized stroke rats. Interestingly, nonpinealectomized vehicle-infused stroke rats, as well as pinealectomized transplanted stroke rats, had significantly lower melatonin levels in the cerebrospinal fluid than nonpinealectomized transplanted stroke rats. We conclude that intracerebral transplantation of pineal gland, in the presence of host intact pineal gland, protected against stroke, possibly through secretion of melatonin.

Animals↗
PubMed2001

Rapid responses of British butterflies to opposing forces of climate and habitat change.

Habitat degradation and climate change are thought to be altering the distributions and abundances of animals and plants throughout the world, but their combined impacts have not been assessed for any species assemblage. Here we evaluated changes in the distribution sizes and abundances of 46 species of butterflies that approach their northern climatic range margins in Britain-where changes in climate and habitat are opposing forces. These insects might be expected to have responded positively to climate warming over the past 30 years, yet three-quarters of them declined: negative responses to habitat loss have outweighed positive responses to climate warming. Half of the species that were mobile and habitat generalists increased their distribution sites over this period (consistent with a climate explanation), whereas the other generalists and 89% of the habitat specialists declined in distribution size (consistent with habitat limitation). Changes in population abundances closely matched changes in distributions. The dual forces of habitat modification and climate change are likely to cause specialists to decline, leaving biological communities with reduced numbers of species and dominated by mobile and widespread habitat generalists.

Adaptation, Physiological↗
PubMed2001

Adoptive transfer of autologous Epstein-Barr virus-specific cytotoxic T cells for nasopharyngeal carcinoma.

Tumor cells from NPC patients are regularly and latently infected with EBV. To examine whether the virus serves as target for immune intervention of the cancer, we determined levels of EBV-specific CTLp in peripheral blood from NPC patients, long-term survivors of the cancer and healthy subjects. CTLp levels of test subjects varied between 3- 3,000/10(6) PBMCs. The plasma EBV burden increased when the CTLp level fell below 150, whereas the EBV burden of PBMCs was not correlated with CTLp level. Compared with healthy carriers, CTLp levels of patients were lower and varied over a wider range, between 3-1,500/10(6) PBMCs. The quantitative immune deficit was probably attributed to the tumor because, first, CTLp in survivors was restored to levels similar to those in healthy carriers after the tumor had been successfully treated. Second, the CTLp level changed as disease progressed, being lower in local disease, increased in locoregional disease and decreased again when the tumor metastasized. Based on these findings, 4 patients with advanced disease were infused with 5 x 10(7)-3 x 10(8) autologous EBV CTLs. The treatment was safe and unaccompanied by inflammatory or other complications, but whether it improved tumor control could not be discerned from the large tumor bulk. Nevertheless, the treatment regularly increased CTLp levels of patients, maintained it at higher levels for protracted periods and, in 3 patients, restored host surveillance of EBV replication, reducing the plasma EBV burden. Taken together, these results provided a rationale to further explore EBV as a target of immune intervention of NPC.

Adoptive Transfer↗
PubMed2001

Tyrosine 331 and phenylalanine 334 in Clostridium perfringens alpha-toxin are essential for cytotoxic activity.

Differences in the biological properties of the Clostridium perfringens phospholipase C (alpha-toxin) and the C. bifermentans phospholipase C (Cbp) have been attributed to differences in their carboxy-terminal domains. Three residues in the carboxy-terminal domain of alpha-toxin, which have been proposed to play a role in membrane recognition (D269, Y331 and F334), are not conserved in Cbp (Y, L and I respectively). We have characterised D269Y, Y331L and F334I variant forms of alpha-toxin. Variant D269Y had reduced phospholipase C activity towards aggregated egg yolk phospholipid but increased haemolytic and cytotoxic activity. Variants Y331L and F334I showed a reduction in phospholipase C, haemolytic and cytotoxic activities indicating that these substitutions contribute to the reduced haemolytic and cytotoxic activity of Cbp.

Animals↗
PubMed2001

Early responses to Salmonella typhimurium infection in mice occur at focal lesions in infected organs.

Salmonella typhimurium causes an invasive disease in mice that has similarities to human typhoid, with key roles for cytokines and possibly also inducible nitric oxide synthase (iNOS), in mediating host responses to infection. In this paper we demonstrate that iNOS mRNA, protein and enzyme activity is induced within spleens and livers of infected mice as early as 5 h post-infection. Immunohistochemistry and in situ hybridization indicated that iNOS expression occurs predominantly in macrophages in localized, discrete foci in the infected organs. iNOS activity in spleen and liver was not detectable in uninfected control mice. The presence of mRNA encoding pro-inflammatory cytokines (TNFalpha, IL-1beta and IFNgamma) in infected organs was measured using RT-PCR, all three being present from 2 h post-infection onwards, but not before. These data show that there is a very early host response to S. typhimurium infection in mice, limited to foci within the infected organs.

Animals↗
PubMed2001

On hating in the first person plural: thinking psychoanalytically about racism, homophobia, and misogyny.

On the basis of personal, cultural, and clinical references, misogyny, homophobia, and racism are conceptualized as structured forms of hatred grounded in a defensive use of the first person plural voice. This use of hatred defends against dangers associated with desires linked to the first person singular. In these hatreds, "I want" is defensively transformed into "we hate." Disidentification from and hatred of the object appear where identification and yearning had been. Along with this defensive move into plurality, with these forms of hatred comes the use of what is conceptualized as the "hermeneutics of transparency." Here the hated qualities of the objects in question are sensed to be transparently obvious, a matter not of thought but of perception. The underlying premises of these hatreds are then contrasted with the underlying premises of psychoanalysis. Effective psychoanalytic work with these hatreds entails resisting the moral pressure to disidentify from them, while bearing the often profound discomfort linked with identifying with them.

Attitude↗
PubMed2000

Consensus statement on the live organ donor.

OBJECTIVE: To recommend practice guidelines for transplant physicians, primary care providers, health care planners, and all those who are concerned about the well-being of the live organ donor. PARTICIPANTS: An executive group representing the National Kidney Foundation, and the American Societies of Transplantation, Transplant Surgeons, and Nephrology formed a steering committee of 12 members to evaluate current practices of living donor transplantation of the kidney, pancreas, liver, intestine, and lung. The steering committee subsequently assembled more than 100 representatives of the transplant community (physicians, nurses, ethicists, psychologists, lawyers, scientists, social workers, transplant recipients, and living donors) at a national conference held June 1-2, 2000, in Kansas City, Mo. CONSENSUS PROCESS: Attendees participated in 7 assigned work groups. Three were organ specific (lung, liver, and kidney) and 4 were focused on social and ethical concerns (informed consent, donor source, psychosocial issues, and live organ donor registry). Work groups' deliberations were structured by a series of questions developed by the steering committee. Each work group presented its deliberations to an open plenary session of all attendees. This information was stored and shaped into a statement circulated electronically to all attendees for their comments, and finally approved by the steering committee for publication. The term consensus is not meant to convey universal agreement of the participants. The statement identifies issues of controversy; however, the wording of the entire statement is a consensus by approval of all attendees. CONCLUSION: The person who gives consent to be a live organ donor should be competent, willing to donate, free from coercion, medically and psychosocially suitable, fully informed of the risks and benefits as a donor, and fully informed of the risks, benefits, and alternative treatment available to the recipient. The benefits to both donor and recipient must outweigh the risks associated with the donation and transplantation of the living donor organ.

Health Status↗
PubMed2000

Rapid and sensitive immunomagnetic-electrochemiluminescent detection of staphyloccocal enterotoxin B.

Sensitive, rapid and reproducible detection of staphyloccocal enterotoxin B (SEB) in a range of different biological matrices was achieved using the ORIGEN((R)) Immunoassay System (Igen, Inc). The homologous immunoassay format consisted of a double antibody sandwich in which a biotinylated capture antibody, pre-bound to streptavidin-coated paramagnetic beads, was used to bind antigen from test samples. A detector antibody, labeled with ruthenium (II) tris-bipyridal chelate, was added and, when bound to the bead immunocomplex, generated light in the presence of an excess of tripropylamine. The light was detected and measured by the ORIGEN analyzer. The sensitivity of this assay was 1 pg of enterotoxin per ml of serum, urine, tissue, or buffer and was highly reproducible. Concentration curves generated from SEB standards produced consistently wide linear ranges (0.1-100 ng/ml), making quantitation possible with only two dilutions of sample (undiluted and 1:1000). The assay used 50 microl of sample per test and required a 30 min incubation period in addition to a 1 min per tube reading time (50 tubes maximum). This assay was significantly better in terms of sensitivity, linear range, and assay time than the standard microplate enzyme-linked immunosorbent assay and should permit early SEB detection in clinical samples, food, and environmental samples.

Animals↗
PubMed2000

Information resources for the bioinformatician.

The collaborative computing project in biosequence and structure analysis (CCPII) was established to foster bioinformatics in the broad community and the UK research community in particular. A World-Wide Web site called 'The Bioinformatics Resource' has been created containing a comprehensive set of information resources of use to the bioinformatician. The activities of CCPII are complementary to other providers of molecular biology information such as the BIOSCI electronic communication forum, which was established to facilitate communication between professionals in the biological sciences.

Computational Biology↗
PubMed1998

Cutaneous glands of male and female impalas (Aepyceros melampus): seasonal activity changes and secretory mechanisms.

The cutaneous glands of the forehead and the metatarsus were studied by histological and histochemical methods and electron microscopy in adult male and female impalas in various seasons of the year. All glandular areas consist of apocrine and holocrine glands, which, however, occur in different proportions. Our findings in the apocrine gland cells suggest (1) the synthesis and exocytosis of a glycoproteinaceous secretory product stored in secretory granules, (2) typical apocrine secretion of the transformed apical cytoplasm, and (3) transepithelial fluid transport. The Golgi apparatus and apical membrane have binding sites for several lectins (PNA, HPA, RCA I, WGA). Cytokeratins 7, 14 and 19 are expressed at various intracellular localizations, suggesting an active role in the secretory mechanisms. The glands of the male forehead show marked seasonal changes in activity that are correlated with the main phases of the reproductive cycle, with the highest cellular activity occurring during the rut in April/May. The female forehead glands are only moderately developed and do not undergo seasonal changes. The metatarsal glands are of equal size in males and females and show no seasonal changes in activity. This study supports the hypothesis that (1) forehead glands in the male have a signaling role in the rut and (2) the metatarsal glands have a more general, probably social role maintaining and restoring contact between herd members.

Alcian Blue↗
PubMed1997

On situating homophobia.

Premised on the observation that the HIV epidemic has occasioned an increase in both the prevalence and the virulence of homophobic ideation, feeling, and action, this paper surveys some of the ways in which psychoanalytic theory has been widely used in the emerging extraclinical literature on this problem. The problem has been barely addressed in the clinical literature, however, a gap that is discussed. The paper then proceeds, by way of a clinical vignette and a critical examination of some central texts of Freud, to present a clinical/theoretical perspective on homophobia. This perspective leans on Brian Bird's work on prejudice.

Adult↗
PubMed1997

Potencies of leflunomide and HR325 as inhibitors of prostaglandin endoperoxide H synthase-1 and -2: comparison with nonsteroidal anti-inflammatory drugs.

The relative anti-inflammatory activities of the immunomodulators HR325 and leflunomide, or its active metabolite A77 1726, were examined by determining potencies in vitro on prostaglandin endoperoxide H synthase (PGHS) and in vivo in rat air pouch inflammation. Nonsteroidal anti-inflammatory drugs (NSAIDs) were used as comparators. HR325 was more potent than A77 1726 as an inhibitor of PGHS in guinea pig polymorphonuclear leukocytes (IC50 = 415 and 4400 nM, respectively) and on isolated ovine PGHS-1 (IC50 = 64 and 742 microM) and PGHS-2 (IC50 = 100 and 2766 microM). In vivo, in rat carrageenan air pouch inflammation, HR325 but not leflunomide at 25 mg/kg inhibited accumulation of leukocytes (48%) and PGE2 (61%). HR325 was also more potent than A77 1726 against human peripheral blood mononuclear cell PGHS-1 [IC50 = 1.6 and 25.6 microM (thromboxane B2 production) or 1.1 and 8 microM (PGE2 production)] and lipopolysaccharide-induced PGHS-2 in human adherent peripheral blood mononuclear cells (IC50 = 435 nM and 9.5 microM) and peripheral blood polymorphonuclear leukocytes (IC50 = 91 nM and 3.2 microM). HR325 had low PGHS-2 selectivity in the human (2.5-12-fold) and was a more potent PGHS-2 inhibitor than naproxen, ibuprofen and piroxicam (28-fold). Assays using endogenous arachidonic acid as substrate yielded IC50 values for NSAIDs that were in general markedly lower than those published for assays using 10 microM substrate. With this approach, piroxicam had reasonable activity on human PGHS-2 (IC50 = 260-290 nM). Only NS398 and flufenamic acid were PGHS-2 selective in the human (90-330-fold and 37-60-fold, respectively); the other NSAIDs were either PGHS-1-selective (naproxen, ibuprofen, flurbiprofen and indomethacin) or nonselective (piroxicam and diclofenac). Inclusion of 10% human plasma reduced HR325 potency against PGHS-1 in human peripheral blood mononuclear cells approximately 32-fold (IC50 = 36 microM). Plasma protein binding further reduced HR325 potency (IC50 = 164 microM) and minimized the difference between HR325 and A77 1726 (IC50 = 292 microM) in a whole blood PGHS assay. Whether the greater activity against human PGHS-2 would allow HR325 to exhibit NSAID-like therapeutic effects in humans remains unclear.

Aniline Compounds↗
PubMed1996

Molecular cloning of a partial cDNA of a novel gene in iron metabolism.

In order to elucidate the possible role played by human hepatic ferritin-associated protein in normal cellular iron metabolism and in iron overload diseases, malignancies and hepatic fibrosis, we attempted to isolate genes for ferritin associated proteins. Here we describe the cloning of a novel cDNA fragment of a 10 kb mRNA transcript from human liver and human T lymphoid (MOLT-4) cells using a short degenerate 5'-primer derived from six amino acid residues of an affinity purified ferritin associated protein from human liver. Northern analysis of this clone has revealed the presence of a 10 kb mRNA species in both human liver and MOLT-4 cell RNA.

Amino Acid Sequence↗