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D Walsh

Publications and source records attributed to D Walsh.

At least 55 records · Page 3Linked to original sources
PubMed2001

Thermal resistance of wild-type and antibiotic-resistant Listeria monocytogenes in meat and potato substrates.

AIMS: This study aimed to elucidate the relationship, if any, between the acquisition/possession of antibiotic resistance in strains of Listeria monocytogenes and the resistance of such strains to heat stress. METHODS AND RESULTS: D-values calculated using a linear survival model were used to compare the heat resistance of two wild-type (WT) and two antibiotic (streptomycin)-resistant (AR) mutant strains of L. monocytogenes measured in minced beef and potato substrates at 55 degrees C, with and without prior heat shock at 48 degrees C. In both minced beef and potato, no significant differences (P < 0.05) between D-values of AR and WT strains were noted. Heat shock did not significantly increase D-values of WT or AR strains in minced beef, while in potato slices, D-values in almost all cases were significantly higher in samples which had received heat-shock treatment. In minced beef, the use of a non-selective/overlay recovery medium did not result in higher D-values for any strains, while in potato, significantly higher (P < 0.05) D-values were obtained in most cases. CONCLUSION: The presence or absence of antibiotic resistance genes did not modulate the heat resistance of the strains examined in this study. SIGNIFICANCE AND IMPACT OF THE STUDY: The study demonstrated that heat shock, and the type of media used to determine bacterial numbers during heat processing, can significantly affect the D-values obtained.

Drug Resistance, Microbial↗
PubMed2001

Comparison of selective and non-selective enrichment media in the detection of Listeria monocytogenes from meat containing Listeria innocua.

AIMS: This study investigated whether the higher incidence of recovery from meat of Listeria innocua compared with L. monocytogenes could be due to the laboratory media used, leading to an artificially lower detection of the pathogenic species, L. monocytogenes. METHODS AND RESULTS: Minced beef was inoculated with L. monocytogenes, L. innocua, or a mixture of these species, and stored at 0 or 10 degrees C under vacuum or aerobic conditions for up to 28 days. Listeria were recovered from the minced beef using selective (University of Vermont Medium, UVM) and non-selective (Buffered Peptone Water, BPW) enrichment broths after 0, 14, and 28 days of storage. In general, there were no significant differences (P < 0.05) between the numbers of L. monocytogenes recovered from minced beef samples after 24 h enrichment in BPW and the numbers recovered using UVM. In addition, the presence of L. innocua in meat samples containing L. monocytogenes did not significantly (P < 0.05) affect the numbers of L. monocytogenes recovered using either enrichment broth. In most cases there were no significant differences (P < 0.05) between the numbers of L. innocua recovered from minced beef samples after 24 h enrichment in BPW compared with numbers recovered using UVM. CONCLUSION: Listeria innocua was found to have no significant competitive advantage over L. monocytogenes in selective or non-selective enrichment media. SIGNIFICANCE AND IMPACT OF THE STUDY: The results suggest that, in some instances, the use of a selective enrichment broth offers no advantage over a non-selective enrichment broth for the recovery of Listeria species from minced beef.

Bacterial Typing Techniques↗
PubMed2001

A comparison of partnership caseload midwifery care with conventional team midwifery care: labour and birth outcomes.

OBJECTIVES: to compare the effects of partnership caseload midwifery care, with conventional team midwifery care. Comparisons of labour interventions and birth outcomes were made between the two models of care. DESIGN: a prospective, non-randomised clinical trial. SETTING: Women's Hospital at Leicester Royal Infirmary, Leicester, UK in 1998. PARTICIPANTS: 303 women from the experimental group and 308 from the control group (611 in total) matched for age, ethnicity, marital status, parity, gravida and height who gave birth between April 1997 and August 1998. INTERVENTION: the control group received conventional team midwifery care during pregnancy, labour and birth, and the experimental group received care from midwives working in partnerships that provided continuity of care during pregnancy, labour and birth. KEY FINDINGS: 21% of women in the experimental group had an epidural compared with 32% of the controls (OR 0.56 95%, CI 0.39-0.81, P=0.002). The normal vaginal birth rate (74% v 66%, OR 1.45, 95% CI 1.02-2.05, P=0.038), upright birth posture rate (60% v 14%, OR 9.64, 95% CI 5.96-15.61, P= or <0.001), intact perineum rate (40% v 30%, OR 1.57, 95% CI 1.05-2.35, P=0.027), and physiological third stage rate (37% v 1.5%, OR 38.69, 95% CI 11.98-124.89, P= or <0.001) were significantly higher in the experimental group. The induction of labour rate (16% v 23%, OR 0.66, 95% CI 0.44-0.98, P=0.042) was significantly lower in the experimental group. Women in the experimental group had more home births (17% v 1.3%, OR 15.38. 95% CI 5.48-43.14, P= or <0.001); used the midwife-led birthing suite more often (28% v 12%, OR 2.77, 95% CI 1.82-4.22, P= or <0.001); were more likely to take an early discharge (two to six hours) from hospital following birth (25% v 3%, OR 11.32. 95% CI 5.55-23.06, P= or <0.001); and were attended in birth more often by either their named midwife (67% v 5%, OR 39.65, 95% CI 22.38-70.25, P= or <0.001) or her partner (known midwife) (84% v 14%, OR 32.74, CI 20.96-51.14, P= or <0.001). IMPLICATIONS FOR PRACTICE: partnership caseload midwifery care resulted in less interventionist labour and more normal birth than conventional team midwifery care. Women in the experimental group had more home births, birth in a midwife-led suite and opted for early discharge home postnatally more often than the controls. They also experienced much higher levels of continuity, particularly of a known midwife during labour and birth. The study findings should encourage other maternity units in the UK to pilot and evaluate the model to see if these benefits are transferable.

Adult↗
PubMed2001

Validity and use of a non-parallel insulin assay for pharmacokinetic studies of the rapid-acting insulin analogue, insulin aspart.

A radioimmunoassay (RIA) for insulin was validated for reliable measurement of the human insulin analogue, insulin aspart, by correction of non-linear measurements. Specificity was equivalent for several species of insulin, except insulin aspart. A non-linear hyperbolic model fitted insulin aspart with a correction formula for non-linearity of: z = 1,503y/ (1,398 - y), where y denotes measured concentration and z denotes true concentration. Matrix-effects were insignificant for human, porcine, and canine heparin-plasma and for human and porcine serum. The coefficient of variation was below 15% for 80-800 pmol/L human and porcine insulin and for 80-600 pmol/L insulin aspart. The limit of detection for insulin aspart was 11.5 pmol/L with a lower limit of quantification of 17.5 pmol/ L. Dilution of serum with Pharmacia dilution media introduced no significant error. In conclusion, this paper demonstrates that a non-parallel radioimmunoassay can be used to estimate accurate concentrations of insulin aspart.

Animals↗
PubMed2001

Outcomes following coronary artery bypass grafting and percutaneous transluminal coronary angioplasty in the stent era: a prospective study of all 9890 consecutive patients operated on in Scotland over a two year period.

OBJECTIVE: To determine current outcomes of percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG). DESIGN: The Scottish coronary revascularisation register provided prospectively collected data on case mix and in-hospital complications for all revascularisation procedures between April 1997 and March 1999 (4775 PTCA; 5115 CABG). Linkage to routine hospital discharge and death data provided follow up information on survival and repeat revascularisation. RESULTS: Stents were used in 51% of PTCA procedures. CABG patients were older, had more severe coronary disease, and had greater comorbidity. PTCA was more likely to be undertaken as an urgent or emergency procedure. Perioperative death and urgent surgery followed 0.3% and 0.6% of PTCA procedures, respectively. Case fatality rates were higher following CABG, with 6.7% dead within two years compared with 3.4% following PTCA. PTCA was more often followed by readmission for ischaemic heart disease, repeat angiography, or revascularisation: 22.8% of patients had repeat revascularisation within two years, compared with 1.8% following CABG. CONCLUSIONS: The severity of coronary heart disease was greater than in previously published registry studies and randomised trials. Despite this, overall survival figures were comparable and repeat revascularisation rates lower, particularly following PTCA. Perioperative death and urgent surgery following PTCA were also lower. These favourable outcomes may be attributable, in part, to increased use of bail out and elective stenting.

Aged↗
PubMed2001

Recovery from psychotic illness: a 15- and 25-year international follow-up study.

BACKGROUND: Poorly defined cohorts and weak study designs have hampered cross-cultural comparisons of course and outcome in schizophrenia. AIMS: To describe long-term outcome in 18 diverse treated incidence and prevalence cohorts. To compare mortality, 15- and 25-year illness trajectory and the predictive strength of selected baseline and short-term course variables. METHODS: Historic prospective study. Standardised assessments of course and outcome. RESULTS: About 75% traced. About 50% of surviving cases had favourable outcomes, but there was marked heterogeneity across geographic centres. In regression models, early (2-year) course patterns were the strongest predictor of 15-year outcome, but recovery varied by location; 16% of early unremitting cases achieved late-phase recovery. CONCLUSIONS: A significant proportion of treated incident cases of schizophrenia achieve favourable long-term outcome. Sociocultural conditions appear to modify long-term course. Early intervention programmes focused on social as well as pharmacological treatments may realise longer-term gains.

Adult↗
PubMed2001

Terminal care in the home--the general practice perspective.

A postal survey of 200 General Practitioners in south Dublin was undertaken. The aim was to elicit information about the problems experienced by GPs when caring for terminally ill cancer patients at home, and about their perceived needs for both further training and support services. All respondents experienced problems at least occasionally with control of pain and other symptoms. 25% of GPs surveyed frequently experienced difficulty with access to hospice in-patient beds, and with inadequate home support services. Overall, satisfaction with specialist Palliative Care Services was high. The majority of GPs felt that they would benefit from further education in Palliative Medicine. They also nominated ways to help them improve care of terminally ill patients at home including further training in pain control and symptom relief, more general and specialist nursing support, and more specialist medical support in the community.

Family Practice↗
PubMed2001

Electronic health summaries--building on the foundation of Scottish Record Linkage system.

Developing electronic patient records is currently a priority for Health Services, so that the clinician treating the patient has all the relevant information available on the desktop. However, as with paper records, there is the danger of information overload, with key information being missed. It is now recognized that electronic health summaries of patient events will be needed. This paper describes the Scottish Record Linkage system, which has been routinely used over the last 10 years to build event histories for patients in the NHS in Scotland. Probability matching has been used to identify records belonging to an individual since a unique patient identification number has not been in general use. We present examples of use of this rich information resource, either for clinical decision making, evidence based medicine, or population needs assessment, and investigate how the system may be developed in a data-warehousing environment to populate electronic health summaries for the five million residents of Scotland.

Decision Making↗
PubMed2000

Mutagenicity in lung of big Blue((R)) mice and induction of tandem-base substitutions in Salmonella by the air pollutant peroxyacetyl nitrate (PAN): predicted formation of intrastrand cross-links.

Peroxyacetyl nitrate (PAN) is a ubiquitous air pollutant formed from NO(2) reacting with acetoxy radicals generated from ambient aldehydes in the presence of sunlight and ozone. It contributes to eye irritation associated with photochemical smog and is present in most urban air. PAN was generated in a chamber containing open petri dishes of Salmonella TA100 (gas-phase exposure). After subtraction of the background mutation spectrum, the spectrum of PAN-induced mutants selected at 3.1-fold above the background mutant yield was 59% GC-->TA, 29% GC-->AT, 2% GC-->CG, and 10% multiple mutations - primarily GG-->TT tandem-base substitutions. Using computational molecular modeling methods, a mechanism was developed for producing this unusual tandem-base substitution. The mechanism depends on the protonation of PAN near the polyanionic DNA to release NO(2)(+) resulting in intrastrand dimer formation. Insertion of AA opposite the dimerized GG would account for the tandem GG-->TT transversions. Nose-only exposure of Big Blue((R)) mice to PAN at 78ppm (near the MTD) was mutagenic at the lacI gene in the lung (mutant frequency +/-S.E. of 6.16+/-0.58/10(5) for controls versus 8.24+/-0.30/10(5) for PAN, P=0.016). No tandem-base mutations were detected among the 40 lacI mutants sequenced. Dosimetry with 3H-PAN showed that 24h after exposure, 3.9% of the radiolabel was in the nasal tissue, and only 0.3% was in the lung. However, based on the molecular modeling considerations, the labeled portion of the molecule would not have been expected to have been bound covalently to DNA. Our results indicate that PAN is weakly mutagenic in the lungs of mice and in Salmonella and that PAN produces a unique signature mutation (a tandem GG-->TT transversion) in Salmonella that is likely due to a GG intrastrand cross-link. Thus, PAN may pose a mutagenic and possible carcinogenic risk to humans, especially at the high concentrations at which it is present in some urban environments.

Air Pollutants↗
PubMed2000

Family characteristics of deficit and nondeficit schizophrenia in the Roscommon Family Study.

Studies of course, treatment response, biological correlates, and environmental risk factors have suggested that the deficit syndrome of schizophrenia defines a meaningful subgroup within schizophrenia. Probands from the Roscommon Family Study who met criteria for schizophrenia or simple schizophrenia were categorized into deficit (N=22) and nondeficit (N=111). Within schizophrenia, the lifetime prevalence of the deficit syndrome was 16.5%; the percentage of males was 91% compared to 63% in the nondeficit group. The first-degree relatives of deficit probands had a significantly greater social isolation than the relatives of nondeficit probands, despite significantly less severe dysphoria and psychotic-like symptoms. The risk of schizophrenia was 1.75 times greater in the families of deficit compared to nondeficit probands. There were no significant differences in the adjusted morbid risk for nonaffective psychosis, affective disorder, or alcoholism. These results provide further evidence that the deficit syndrome is a marker of a group of patients with clinical and neurobiological characteristics that distinguish them from the rest of schizophrenia. The deficit syndrome may be a useful phenotype in genetic linkage studies.

Female↗
PubMed2000

Multicenter linkage study of schizophrenia candidate regions on chromosomes 5q, 6q, 10p, and 13q: schizophrenia linkage collaborative group III.

Schizophrenia candidate regions 33-51 cM in length on chromosomes 5q, 6q, 10p, and 13q were investigated for genetic linkage with mapped markers with an average spacing of 5.64 cM. We studied 734 informative multiplex pedigrees (824 independent affected sibling pairs [ASPs], or 1,003 ASPs when all possible pairs are counted), which were collected in eight centers. Cases with diagnoses of schizophrenia or schizoaffective disorder (DSM-IIIR criteria) were considered affected (n=1,937). Data were analyzed with multipoint methods, including nonparametric linkage (NPL), ASP analysis using the possible-triangle method, and logistic-regression analysis of identity-by-descent (IBD) sharing in ASPs with sample as a covariate, in a test for intersample heterogeneity and for linkage with allowance for intersample heterogeneity. The data most supportive for linkage to schizophrenia were from chromosome 6q; logistic-regression analysis of linkage allowing for intersample heterogeneity produced an empirical P value <.0002 with, or P=.0004 without, inclusion of the sample that produced the first positive report in this region; the maximum NPL score in this region was 2.47 (P=.0046), the maximum LOD score (MLS) from ASP analysis was 3.10 (empirical P=.0036), and there was significant evidence for intersample heterogeneity (empirical P=.0038). More-modest support for linkage was observed for chromosome 10p, with logistic-regression analysis of linkage producing an empirical P=. 045 and with significant evidence for intersample heterogeneity (empirical P=.0096).

Chromosome Mapping↗
PubMed2000

Neurons regulate extracellular levels of amyloid beta-protein via proteolysis by insulin-degrading enzyme.

Progressive cerebral accumulation of amyloid beta-protein (Abeta) is an early and invariant feature of Alzheimer's disease. Little is known about how Abeta, after being secreted, is degraded and cleared from the extracellular space of the brain. Defective Abeta degradation could be a risk factor for the development of Alzheimer's disease in some subjects. We reported previously that microglial cells release substantial amounts of an Abeta-degrading protease that, after purification, is indistinguishable from insulin-degrading enzyme (IDE). Here we searched for and characterized a role for IDE in Abeta degradation by neurons, the principal cell type that produces Abeta. Whole cultures of differentiated pheochromocytoma (PC12) cells and primary rat cortical neurons actively degraded endogenously secreted Abeta via IDE. However, unlike that in microglia, IDE in differentiated neurons was not released but localized to the cell surface, as demonstrated by biotinylation. Undifferentiated PC12 cells released IDE into their medium, whereas after differentiation, IDE was cell associated but still degraded Abeta in the medium. Overexpression of IDE in mammalian cells markedly reduced the steady-state levels of extracellular Abeta(40) and Abeta(42), and the catalytic site mutation (E111Q) abolished this effect. We observed a novel membrane-associated form of IDE that is approximately 5 kDa larger than the known cytosolic form in a variety of cells, including differentiated PC12 cells. Our results support a principal role for membrane-associated and secreted IDE isoforms in the degradation and clearance of naturally secreted Abeta by neurons and microglia.

Alzheimer Disease↗
PubMed2000

Molecular characterization of the expression of distinct classes of cyclins during the early development of tomato fruit.

Early fruit development in tomato (Lycopersicon esculentum Mill.) proceeds from two distinct phases of growth, essentially cell division and cell expansion. In this study, we investigated the expression characteristics of the key cell-cycle regulators, mitotic and G1 cyclins, during tomato fruit development. We isolated six genes designated Lyces;CycA1;1, Lyces;CycA2;1, Lyces; CycA3;1, Lyces;CycB1:1 and Lyces;CycB2;1 encoding tomato mitotic cyclins, and Lyces;CycD3;1 encoding a G1 cyclin. The accumulation of transcripts was predominantly associated with mitotically active organs: developing fruits, young leaves and roots, and with cell-suspension cultures under appropriate sugar feeding conditions. Transcripts for all the isolated cyclin genes could be detected in the epidermis and pericarp of fruit tissues where some slight mitotic activity still remained at the onset of ripening. However, Lyces;CycA3;1 and Lyces;CycD3;1 were expressed in the gel tissue at the late stage of fruit development, suggesting that they are involved in endoreduplication of the differentiated and giant cells of the gel tissue.

Amino Acid Sequence↗
PubMed2000

Infectious complications of advanced cancer.

We present a retrospective study of the frequency, pattern, and management of infections in advanced cancer. Three hundred ninety-three patients were admitted to an acute care palliative medicine unit in an 8-month period for evaluation and palliation of cancer-related symptoms and complications. One hundred fifteen had at least one positive bacteriological culture, and 100 of these patients were evaluable. One hundred fifty-two infections and 192 isolates were identified. Sixty-eight patients had polymicrobial infections. Sixty-six patients had urinary tract infections. Forty-one were found to have multisystemic infections. Eighty-one had invasive devices; 32 had more than one invasive device. Fifty-three were taking corticosteroids at the time of infection. Only 3 were neutropenic. Urinary tract infections were significantly more common in those taking corticosteroids. The median duration of antibiotic treatment was 11 days and the median hospital stay, 14 days. Twenty-eight patients died in the hospital; 10 of those who died had lung cancer, which was a statistically significant observation. In conclusion, infections are an underrecognized but common complication in nonneutropenic hospitalized patients with advanced solid tumors. Urinary tract infections appear to be associated with the use of corticosteroids. Lung cancer patients are at greater risk for fatal infections. Infections increase morbidity in debilitated patients with solid tumors, are a frequent cause of hospital admission, and are associated with significant mortality.

Adult↗
PubMed2000

Treatment of nausea and vomiting in advanced cancer.

Nausea and vomiting unrelated to chemotherapy is common in advanced cancer patients. The etiology of nausea and vomiting may from evident by the pattern of vomiting, associated symptoms, review of medications and physical examination. Radiographic studies are particularly helpful if bowel obstruction is suspected or central nervous system metastases are a possibility. Laboratory studies are helpful in a minority of cases. Multiple classes of medications are available to palliate nausea and vomiting. Classes of agents are discussed, pharmacology and cost being among the aspects covered. A four-step approach to the medical management of nausea and vomiting is presented.

Antiemetics↗
PubMed2000

Psychostimulants in supportive care.

Psychostimulant medications have been used clinically and investigated in psychiatric populations, the medically ill, cancer patients and healthy people. This article discusses the pharmacology of dextroamphetamine, methylphenidate, pemoline (and other psychostimulants such as caffeine and ephedrine), their use in general medicine and cancer care, side effects, and abuse potential. Therapeutic use in children is addressed only insofar as it illustrates facets of their use in adults.

Adult↗
PubMed2000

The symptoms of advanced cancer: relationship to age, gender, and performance status in 1,000 patients.

A multivariate analysis of the data was conducted to evaluate the effects of age, gender, and performance status on symptom profile. A comprehensive prospective analysis of symptoms was conducted in 1,000 patients on initial referral to the Palliative Medicine Program of the Cleveland Clinic. The median number of symptoms per patient was 11 (range 1-27). The ten most prevalent symptoms were pain, easy fatigue, weakness, anorexia, lack of energy, dry mouth, constipation, early satiety, dyspnea, and greater than 10% weight loss. The prevalence of these 10 symptoms ranged from 50% to 84%. Younger age was associated with 11 symptoms: blackout, vomiting, pain, nausea, headache, sedation, bloating, sleep problems, anxiety, depression, and constipation. Gender was associated with 8 symptoms. Males had more dysphagia, hoarseness, >10% weight loss and sleep problems; females, more early satiety, nausea, vomiting, and anxiety. Performance status was associated with 14 symptoms. Advanced cancer patients are polysymptomatic. Ten symptoms are highly prevalent. Symptom prevalence for 24 individual symptoms differs with age, or gender, or performance status.

Adolescent↗