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Biomedical subjects

S J Newman

Publications and source records attributed to S J Newman.

At least 19 recordsLinked to original sources
PubMed2006

Contrasting patterns of genetic structure in two species of the coral trout Plectropomus (Serranidae) from east and west Australia: introgressive hybridisation or ancestral polymorphisms.

Inter-specific genetic relationships among regional populations of two species of grouper (Plectropomus maculatus and Plectropomus leopardus) were examined using mitochondrial and nuclear markers. mtDNA revealed contrasting regional inter-specific patterns whilst nuclear markers revealed contrasting patterns among markers, irrespective of region. In eastern Australia (EA) the species form a single mtDNA lineage, but the two species are reciprocally monophyletic in Western Australia (WA). This supports previous evidence for hybridisation between these species on the east coast. WA P. leopardus forms a sister relationship with the EA P. leopardus-maculatus clade while WA P. maculatus is more basal and sister to the P. leopardus lineages, indicating mtDNA does not suffer from incomplete lineage sorting for these species. In contrast, one of three nuclear markers (locus 7-90TG) differentiated the species into two reciprocally monophyletic clades, with no evidence of hybridisation or ancestral polymorphism. The remaining two nuclear markers (2-22 and ETS-2) did not separate these two species, while distinguishing other plectropomid species, suggesting incomplete lineage sorting at these nuclear loci. These results together with coalescence analyses suggest that P. leopardus females have hybridised historically with P. maculatus males and that P. maculatus mitochondria were displaced through introgressive hybridisation and fixation in the P. maculatus founder population on the Great Barrier Reef. The contrasting regional patterns of mtDNA structure may be attributed to Quaternary sea-level changes and shelf width differences driving different reef configurations on each coast. These reef configurations have provided opportunities for local scale interaction and reproduction among species on the narrower EA continental shelves, but not on the broader WA continental shelves.

Animals↗
PubMed2006

Histologic assessment and grading of the exocrine pancreas in the dog.

Histologic grading schemes for canine inflammatory conditions are sparse, and in the case of the canine pancreas, have not been previously described. In a previous study, we determined that histologic lesions of the exocrine pancreas occurred much more frequently than gross lesions. The intention of the current study was to develop a histologic grading scheme for nonneoplastic lesions following extensive assessment of the exocrine pancreas from dogs presented for necropsy examination. The parameters of the proposed scheme include neutrophilic inflammation, lymphocytic inflammation, pancreatic necrosis, pancreatic fat necrosis, edema, fibrosis, atrophy, and hyperplastic nodules. In this case series, the most common lesion was pancreatic hyperplastic nodules (80.2%), followed by lymphocytic inflammation (52.5%), fibrosis (49.5%), atrophy (46.5%), neutrophilic inflammation (31.7%), pancreatic fat necrosis (25.7%), pancreatic necrosis (16.8%), and edema (9.9%). Only 8 of the 101 animals had no evidence of any of the lesions in any of the sections examined. Fibrosis, atrophy, and/or lymphocytic infiltration most commonly accompanied nodules. Neutrophilic inflammation, when present, was often associated with necrosis (pancreatic necrosis, pancreatic fat necrosis, or both) and occasionally with hyperplastic nodules. The utilization of a grading scheme for exocrine pancreatic lesions will be useful in advancing the classification of exocrine pancreatic disease in the dog, which may lead to multicenter studies of exocrine pancreatic disorders in the dog and in other species.

Animals↗
PubMed2006

Marine mammal neoplasia: a review.

A review of the published literature indicates that marine mammal neoplasia includes the types and distributions of tumors seen in domestic species. A routine collection of samples from marine mammal species is hampered, and, hence, the literature is principally composed of reports from early whaling expeditions, captive zoo mammals, and epizootics that affect larger numbers of animals from a specific geographic location. The latter instances are most important, because many of these long-lived, free-ranging marine mammals may act as environmental sentinels for the health of the oceans. Examination of large numbers of mortalities reveals incidental proliferative and neoplastic conditions and, less commonly, identifies specific malignant cancers that can alter population dynamics. The best example of these is the presumptive herpesvirus-associated metastatic genital carcinomas found in California sea lions. Studies of tissues from St. Lawrence estuary beluga whales have demonstrated a high incidence of neoplasia and produced evidence that environmental contamination with high levels of polychlorinated biphenols and dichlorophenyl trichloroethane might be the cause. In addition, viruses are suspected to be the cause of gastric papillomas in belugas and cutaneous papillomas in Florida manatees and harbor porpoises. While experimental laboratory procedures can further elucidate mechanisms of neoplasia, continued pathologic examination of marine mammals will also be necessary to follow trends in wild populations.

Animals↗
PubMed2005

Canine hepatic neuroendocrine carcinoma: an immunohistochemical and electron microscopic study.

Ten dogs with neuroendocrine carcinoma of the liver were selected for inclusion in the study. Clinical signs were anorexia (7), vomiting (5), polydipsia/polyuria (3), icterus (2), lethargy (2), weight loss (2), paresis (1), ataxia (1), weakness (1), collapse (1), and urinary tract infection (1). Hematologic and biochemical abnormalities included anemia (2/8), leukocytosis (4/8), high liver enzyme activity (serum alkaline phosphatase, 7/9; alanine transaminase, 7/9; aspartate transaminase, 8/9), and high total bilirubin (6/9). Grossly, the tumors were diffuse, involving all liver lobes in six dogs, and two dogs had various-sized nodules in addition to diffuse involvement. Histologically, there were eight tumors with solid or trabecular pattern (group A), one tumor with cords or rows of neoplastic cells (group B), and one tumor with multiple rosette-like structures (group C). Immunohistochemical studies revealed that all 10 neoplasms were positive for at least one of the endocrine markers used: neuron-specific enolase (NSE; 8/10), synaptophysin (5/10), and chromogranin-A (3/10). A panel of NSE, chromagranin-A, and synaptophysin detected 100% of the tumors in our series. Electron microscopy confirmed the diagnosis by the presence of intracytoplasmic neurosecretory granules in the two examined cases. Our results show that neuroendocrine markers commonly used in humans can be used for the diagnosis of hepatic neuroendocrine carcinoma in dogs, preferably a panel of synaptophysin, chromagranin-A, and NSE because chromogranin-A alone is not as useful in dogs as in humans.

Animals↗
PubMed2005

Correlation of age and incidence of pancreatic exocrine nodular hyperplasia in the dog.

The purpose of this study was to determine the prevalence of pancreatic nodular hyperplasia (NH) and its relation to age in the dog. A total of 101 dogs were enrolled. The pancreas was evaluated by histology and hyperplastic lesions were detected and scored. Age was recorded from the medical records. Correlation of age with inflammation and presence of hyperplastic lesions was evaluated. Of the 101 dogs, 81 (80.2%) had evidence of NH. Twenty-five of the 101 dogs did not have evidence of pancreatic inflammation, necrosis, and/or fibrosis, 17 (68.0%) of which had evidence of NH. Mean +/- SD age in dogs with NH was significantly higher compared with dogs without NH (9.5 +/- 3.4 years versus 3.4 +/- 3.3; P-value < 0.0001). We conclude that NH is a common pathologic lesion in dogs and shows a positive correlation with age regardless of the presence or absence of pancreatic inflammation, necrosis, or fibrosis.

Age Factors↗
PubMed2001

A completely foreign receptor can mediate an interferon-gamma-like response.

A tripartite receptor comprising the external region of the erythropoietin (Epo) receptor, the transmembrane and JAK-binding domains of the gp130 subunit of the interleukin-6 (IL-6) receptor, and a seven amino acid STAT1 recruitment motif (Y440) from the interferon (IFN)-gamma receptor, efficiently mediates an IFN-gamma-like response. An analogous completely foreign chimeric receptor in which the Y440 motif is replaced with the Y905 motif from gp130 also mediates an IFN-gamma-like response, but less efficiently. The IFNGR1 signal-transducing subunit of the IFN-gamma receptor is tyrosine phosphorylated through the chimeric receptors and the endogenous IL-6 and OSM receptors. Cross phosphorylation of IFNGR1 is not, however, required for the IFN-gamma-like response through the chimeric receptors, nor does it mediate an IFN-gamma-like response to IL-6 or OSM. The data argue strongly for modular JAK/STAT signalling and against any rigid structural organization for the "pathways" involved. They emphasize the likely high degree of overlap between the signals generated from disparate JAK-receptor complexes and show that relatively minor changes in such complexes can profoundly affect the response.

DNA-Binding Proteins↗
PubMed2001

Housing attributes and serious mental illness: implications for research and practice.

OBJECTIVES: This paper critically reviews studies of the relationship between housing attributes and serious mental illness, highlights important gaps in the research, generates hypotheses to be tested, and suggests a research agenda. METHODS: Studies published between 1975 and March 2000 were identified through computerized searches, previous literature reviews, and consultation with mental health and housing researchers. Criteria for inclusion included the presentation of quantitative evidence, a systematic sample of known generalizability, and systematic analytic techniques. RESULTS AND CONCLUSIONS: The 32 studies that met these criteria relied on one or more of three conceptualizations of the role of housing: housing attributes or assessments as an outcome or dependent variable; housing attributes as inputs or independent variables in a model in which the outcome pertains to a nonhousing factor, such as a mental health outcome; or housing as both an input and an outcome. Three studies found no long-term effect of improved housing adequacy on housing satisfaction above and beyond case management. Three studies found better outcomes for settings that have fewer occupants. Another study suggested that persons who live in small-scale, good-quality, noninstitutional environments are less likely to engage in disruptive behavior when a larger proportion of other tenants also have serious mental illness. The strongest finding from the literature on housing as an input and an outcome was that living in independent housing was associated with greater satisfaction with housing and neighborhood. Most of the studies had methodological weaknesses, and few addressed key hypotheses. There is a critical need for a coherent agenda built around key hypotheses and for a uniform set of measures of housing an input and an outcome.

Activities of Daily Living↗
PubMed2000

Neuron-specific localisation of the TR3 death receptor in Alzheimer's disease.

Death receptors are associated with the homeostatic and pathologic induction of cell death. TR3 is a recently characterised member of the death receptor family that is expressed in the adult brain. In order to establish the role of TR3 in acute CNS disease and chronic neurodegeneration, we analysed brain regions from Alzheimer's disease (AD), stroke and neurotrauma patients, using a novel anti-peptide antibody generated to an exposed epitope in the extracellular domain of the receptor. We show a statistically significant increase in TR3 protein levels in AD brain samples but not in stroke, neurotrauma or control samples. The increase observed for TR3 was specific to neurons in regions associated with AD pathology. This is the first report describing the neuron-specific regulation of a death receptor in chronic disease and may indicate that a TR3 receptor-mediated signalling pathway is involved in AD-associated neuronal loss.

Aged↗
PubMed2000

Congenital cystic disease of the liver and kidney in a pygmy goat.

A 1-month-old pygmy goat was presented with abdominal distension and hematuria. Anemia, leukocytosis, and increased bilirubin and blood urea nitrogen levels suggested renal and hepatic disease. Radiographs revealed bilateral renomegaly, and ultrasound confirmed bilateral hydronephrosis. Necropsy findings determined that the renomegaly was due in part to edema and marked cystic tubular distension. Similarly, intrahepatic bile ducts were ectatic. The character and distribution of the gross and histologic lesions were consistent with a polycystic disorder, presumably congenital, affecting the liver and the kidney.

Animals↗
PubMed2000

Effect of hormone variations and other factors on symptom severity in women with dystonia.

OBJECTIVE: To determine if any relationship exists between the severity of symptoms in women with dystonia and female reproductive hormonal variations. PATIENTS AND METHODS: We surveyed 279 women with dystonia seen at Mayo Clinic Scottsdale over a 6-year period (1990-1995), and 204 responded. The women were asked questions regarding their reproductive and menstrual histories and dystonia severity and other questions with an emphasis on possible exacerbating or relieving factors. RESULTS: Although in the majority of women hormonal influences had no consistent effect on dystonia symptom severity, 26 (41.9%) of 62 premenopausal women noted a change in the severity of their dystonic symptoms in relation to the 3 phases of their menstrual cycle. Other factors that exacerbated dystonia included stress and fatigue, while sleep improved symptoms. Pregnancy, menopause, and hormone replacement therapy had no effect on symptoms. CONCLUSIONS: Menstrual cycling may result in subjective worsening of dystonia symptoms in some women with dystonia. Further clinical and physiologic evaluation is indicated in such patients, as they may represent an important subgroup of dystonic patients that might yield some clues to the pathophysiology of dystonia and to improved treatment strategies.

Adult↗
PubMed1997

A beta 42 is the predominant form of amyloid beta-protein in the brains of short-term survivors of head injury.

Fatal head injury results in the formation of diffuse parenchymal deposits of amyloid beta-protein (A beta) in the brains of approximately 30% of individuals. We used carboxyl terminal-specific antisera to examine the exact nature of these deposits in paraffin sections of neocortex from seven head-injured patients. Immunostaining for A beta 42 was observed in all parenchymal deposits whereas staining for A beta 40, the form of the protein which predominates in serum and cerebrospinal fluid, was seen in only a small proportion of deposits. The relative paucity of A beta 40 suggests that post-traumatic deposits do not arise as a result of passive leakage from damaged cerebral blood vessels but are similar to the early A beta 42 parenchymal deposits seen in Down's syndrome and Alzheimer's disease.

Adolescent↗
PubMed1996

Neighborhood locations of Section 8 housing certificate users with and without mental illness.

OBJECTIVE: The study examined whether participants with mental illness in the federal Section 8 housing subsidy program settle in neighborhoods different from those of Section 8 participants without mental illness. The nature of these differences and the reasons they occur were also examined. METHODS: Data sources included the Section 8 survey for Baltimore and Cincinnati of the national evaluation of the Robert Wood Johnson Foundation Program on Chronic Mental Illness, police records, and 1990 census tract files, supplemented with the addresses of all Section 8 users and mental health services in both cities. Analyses consisted of calculations of dissimilarity indexes, comparisons of means, and multiple regressions. RESULTS: Dissimilarity index scores were .54 for Baltimore and .48 for Cincinnati, indicating that roughly half of all Section 8 users with mental illness would have to move to eliminate neighborhood disparities between them and Section 8 users without mental illness. Section 8 users with mental illness settled in somewhat better neighborhoods than those without mental illness. This finding was largely attributable to the sizable disparities in the racial composition of the two groups of Section 8 users: a greater proportion of users with mental illness were white. CONCLUSIONS: The neighborhood quality of Section 8 users with mental illness was found to be at least as high as that for users without mental illness. It is not clear whether the Section 8 program of the Program on Chronic Mental Illness disproportionately served whites, although the racial composition of the Section 8 program in both cities is disproportionately black.

Activities of Daily Living↗
PubMed1995

Tissue distribution of the SALMFamide neuropeptides S1 and S2 in the starfish Asterias rubens using novel monoclonal and polyclonal antibodies. I. Nervous and locomotory systems.

The recent isolation and characterization of the SALMFamide neuropeptides (S1 and S2) from the starfish Asterias rubens has initiated a series of single- and double-labelling immunocytochemical studies to ascertain their tissue distribution and cellular localization. Specific novel monoclonal and polyclonal antisera have been raised against these neuropeptides and used in optical immunocytochemistry (ICC). The results of the present study reveal, for the first time, the widespread neuronal distribution of S2 localized to axons and perikarya of the radial nerve cord and tube foot ectoneural nerve plexus. Double labelling revealed a predominantly separate localization for S1 and S2 immunoreactivity. The potential functional roles of S1 and S2 in the radial nerve cord (RNC) and tube feet of Asterias rubens are discussed.

Amino Acid Sequence↗
PubMed1995

Distribution and action of SALMFamide neuropeptides in the starfish Asterias rubens.

The SALMFamides S1 and S2 are two structurally related neuropeptides that are present in starfish, and which share the C-terminal amino acid sequence SXLXFamide, where X is variable. To establish the distribution of S1 and S2 in starfish, we have raised antisera that recognise specifically the C-terminal pentapeptide sequence of either S1 or S2. Here we describe the production and characterisation of an S2-specific antiserum designated CLII. This antiserum, together with an S1-specific antiserum (BLII), has been used in a radioimmunoassay to measure S1 and S2 levels in extracts of body parts from the starfish Asterias rubens. High concentrations (250-400 pmol g-1) of both peptides were detected in the radial nerve cords of the nervous system and lower concentrations were detected in other body parts, including neuromuscular organs such as the tube feet, apical muscle and cardiac stomach. We have examined the pharmacological effects of S1 and S2 on the contractility of these three preparations. Neither S1 nor S2 influenced the tone of tube foot and apical muscle preparations but S2 caused relaxation of cardiac stomach preparations, antagonising the contracting action of acetylcholine.

Animals↗