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S Jones

Publications and source records attributed to S Jones.

At least 181 records · Page 10Linked to original sources
PubMed2000

First in-vivo trials of a fiber Bragg grating based temperature profiling system.

We describe the results of in-vivo trials of a portable fiber Bragg grating based temperature profile monitoring system. The probe incorporates five Bragg gratings along a single fiber and prevents the gratings from being strained. Illumination is provided by a superluminescent diode, and a miniature CCD based spectrometer is used for demultiplexing. The CCD signal is read into a portable computer through a small A/D interface; the computer then calculates the positions of the center wavelengths of the Bragg gratings, providing a resolution of 0.2 degree C. Tests were carried out on rabbits undergoing hyperthermia treatment of the kidney and liver via inductive heating of metallic implants and comparison was made with a commercial Fluoroptic thermometry system.

Animals↗
PubMed2000

Clinical training experience in district general hospitals.

AIMS: To estimate the nature and quantity of clinical experience available for trainees in paediatrics or general practice in acute general hospitals of differing sizes in the UK. To discuss implications for training and service configuration taking account of current Royal College recommendations (a minimum of 1,800 acute contacts each year and ideally covering a population of 450,000 to 500,000 people). METHODS: Observed frequencies of diagnoses in Pinderfields Hospital, Wakefield were compared with those in five other hospitals in Yorkshire and four in the South of England, and with expected frequencies from a review of selected marker conditions using national routine and epidemiological data. Based on the Pinderfields data, we modelled expected frequencies of a wider range of diagnoses for different sized hospitals. RESULTS: Small units (1,800 or less acute referrals a year) provide adequate exposure to common conditions such as gastroenteritis (157 per annum) and asthma (171 per annum) but encounter serious or unusual disease rarely. When modelled for units serving larger populations, numbers of such disorders remain small. For example, about 0.5% of admissions require intensive care to the level of ventilatory support. Medium size units offer a wide range of experience but differ little from those serving the population of 500,000 proposed as being optimal for training. This standard is not justified by the evidence in this review. Closing or amalgamating units on the scale necessary to achieve this ideal would be impractical as only five hospitals in England have a paediatric workload equivalent to this population; it would also raise issues of access and equity.

Adolescent↗
PubMed2000

Effects of varying concentrations of bleach on in vitro HIV-1 replication and the relevance to injection drug use.

The use of bleach (hypochlorite) as a disinfectant for drug injection equipment in the intravenous-drug-using population was recommended early in the HIV-1/AIDS epidemic. Epidemiological studies have challenged the use of bleach as an effective measure to prevent HIV-1 transmission. However, in vitro HIV-1 coculture studies have shown that a high concentration of bleach is an effective cytotoxic and potentially virucidal agent. In this study, we demonstrate that HIV-1 peripheral blood mononuclear cell cocultures containing low concentrations of hypochlorite in the media showed earlier conversion to HIV-1 positivity, as measured by the presence of p24 antigen. HIV-1 cocultures with high concentrations of hypochlorite in the culture media, which appeared to be highly cytotoxic, and HIV-1 cocultures without bleach in the media did not exhibit this early p24 antigen positivity. Hypochlorite chemically disinfects by releasing free chlorine that is a potent oxidant. In injection drug equipment, a low residual concentration of bleach is likely to remain in cleaned equipment despite rinsing with water. Low concentrations of oxidants have been shown to enhance tissue inflammation, in vivo, as well as HIV-1 replication in vitro. Previous studies have shown that despite vigorous cleaning of blood-contaminated injection syringes with bleach followed by water, microaggregates of residual blood remained in bleach-cleaned blood-contaminated syringes. Hypothetically, oxidant effects of the residual bleach in the bleach-cleaned syringes could enhance the possibility of infection by remaining HIV-1 contained in a contaminated syringe. We suggest that the likelihood of an injection drug user contracting HIV-1 through the sharing of a bleach-cleaned blood-contaminated syringe may be increased by the cotransmission of residual bleach and its localized tissue-inflammatory effects; however, this has not been statistically proven in epidemiological studies.

Cell Survival↗
PubMed2000

Deliberate self-harm and antidepressant drugs. Investigation of a possible link.

BACKGROUND: It is not clear if the frequency of deliberate self-harm (DSH) is the same in patients taking different pharmacological classes of antidepressant drugs. AIMS: To compare the frequency of DSH in patients who had been prescribed a tricyclic antidepressant (TCA) or a selective serotonin reuptake inhibitor (SSRI) prior to the DSH event. METHOD: This was a prospective study in 2776 consecutive DSH cases attending an accident and emergency department. The incidence of DSH in TCA-treated cases and SSRI-treated cases is expressed as number of DSH events per 10 000 prescriptions of each antidepressant. RESULTS: Significantly more DSH events occurred following the prescription of an SSRI than that of a TCA (P<0.001). The occurrence of DSH was highest with fluoxetine and lowest with amitriptyline. CONCLUSIONS: Merely prescribing safer-in-overdose antidepressants is unlikely to reduce the overall morbidity from DSH.

Adolescent↗
PubMed2000

Characterization and complementation of a Pichia stipitis mutant unable to grow on D-xylose or L-arabinose.

Pichia stipitis CBS 6054 will grow on D-xylose, D-arabinose, and L-arabinose. D-Xylose and L-arabinose are abundant in seed hulls of maize, and their utilization is important in processing grain residues. To elucidate the degradation pathway for L-arabinose, we obtained a mutant, FPL-MY30, that was unable to grow on D-xylose and L-arabinose but that could grow on D-arabinitol. Activity assays of oxidoreductase and pentulokinase enzymes involved in D-xylose, D-arabinose, and L-arabinose pathways indicated that FPL-MY30 is deficient in D-xylitol dehydrogenase (D-XDH), D- and L-arabinitol dehydrogenases, and D-ribitol dehydrogenase. Transforming FPL-MY30 with a gene for xylitol dehydrogenase (PsXYL2), which was cloned from CBS 6054 (GenBank AF127801), restored the D-XDH activity and the capacity for FPL-MY30 to grow on L-arabinose. This suggested that FPL-MY30 is critically deficient in XYL2 and that the D-xylose and L-arabinose metabolic pathways have xylitol as a common intermediate. The capacity for FPL-MY30 to grow on D-arabinitol could proceed through D-ribulose.

Arabinose↗
PubMed2000

Beacon: a novel gene involved in the regulation of energy balance.

The hypothalamus plays a major role in the control of energy balance via the coordination of several neuropeptides and their receptors. We used a unique polygenic animal model of obesity, Psammomys obesus, and performed differential display polymerase chain reaction on hypothalamic mRNA samples to identify novel genes involved in obesity. In this study, we describe a novel gene that encodes a small protein we have termed "beacon." Beacon mRNA gene expression in the hypothalamus was positively correlated with percentage of body fat. Intracerebroventricular infusion of beacon resulted in a dose-dependent increase in food intake and body weight and an increase in hypothalamic expression of neuropeptide Y (NPY). Simultaneous infusion of beacon and NPY significantly potentiated the orexigenic response and resulted in rapid body weight gain. These data suggest a role for beacon in the regulation of energy balance and body weight homeostasis that may be mediated, at least in part, through the NPY pathway.

Adipose Tissue↗
PubMed2000

Selective intraoperative cholangiography during laparoscopic cholecystectomy: how selective?

The necessity for intraoperative cholangiography during laparoscopic cholecystectomy has been debated for some time. Numerous retrospective studies favor selective intraoperative cholangiography. Surgeons in favor of the selective policy differ in their personal selective criteria. The aim of this prospective study was to evaluate whether intraoperative cholangiography can be safely omitted during laparoscopic cholecystectomy on all patients who fit a standard set of criteria: normal liver function tests, common bile duct diameter less than 10 mm, and no history of gallstone pancreatitis or jaundice. We undertook a prospective study on 155 consecutive patients treated in a county teaching hospital with symptomatic gallbladder disease who met the above standard set of criteria. One hundred and fifty-five patients meeting these criteria underwent laparoscopic cholecystectomy during a 2-year period from February 1996 through February 1998. Data analyzed included patient history, laboratory and ultrasound findings, operative results, postoperative stay, and intraoperative and postoperative complications. The patients were followed by periodic interviews, physical examination, liver function tests, and/or biliary ultrasound for up to 3 1/2 years with a mean follow-up of 26 months for retained common bile duct stones. Intraoperative cholangiography was performed in only one of the 155 patients studied to confirm common bile duct injury. There were four postoperative complications (2.6%) and one common bile injury (0.6%). Postoperative stay averaged one day. No patients, by history, biliary ultrasound, liver function tests or endoscopy, were found to have retained common bile duct stones during the follow-up period. Our study shows that intraoperative cholangiography is not necessary for patients undergoing laparoscopic cholecystectomy who have normal liver functions tests, common bile duct diameter less than 10 mm, and no history of gallstone pancreatitis or jaundice.

Adolescent↗
PubMed2000

Neonatal wound dehiscence and the subsequent healing process: a case study.

Many neonates require abdominal surgery for a variety of reasons, including necrotizing enterocolitis (NEC). Secondary complications of abdominal surgery include alterations in skin integrity and potential wound dehiscence. These alterations may actually worsen when treated with products "traditionally" used postoperatively. The author simultaneously utilized basic wound care products with currently recognized therapies in managing a 29-week premature infant who experienced dehiscence secondary to bowel repair. By utilizing the correct products and incorporating the principles of moist wound healing and occlusion, this Stage III/IV wound, measuring 12 cm x 3 cm, closed within 35 days of dehiscence. A team-oriented and coordinated approach proved that wounds can, and will, improve, even in this fragile population.

Bandages↗
PubMed2000

Herbal tea in the treatment of diabetes mellitus.

OBJECTIVE: To evaluate the effects of a native herbal tea in patients with type 2 diabetes. DESIGN: Randomized, placebo-controlled, single-blind study. SETTING: The Metabolic Centre at the University of Alberta Hospitals. SUBJECTS: Forty volunteers with type 2 diabetes. INTERVENTIONS: After a 1 month "run-in" period, subjects drank 250 mL/d of either the herbal tea or a placebo tea for 10 days, and were followed up for a further 4 weeks. OUTCOME MEASURES: A responder analysis defined as a 10% change in mean blood glucose levels based on 4 capillary glucose readings daily. Secondary end points included changes in HbA1c, fructosamine and response to a meal challenge using Ensure. RESULTS: The responder analysis showed no benefit from the herbal tea. Fructosamine levels before and after tea therapy decreased significantly in both study groups. Mean HbA1c levels and incremental areas under the glucose curve (AUC) in the meal challenge did not change in either study group. These data were reanalysed in hyperglycemic subjects with HbA1c levels greater than 120% of normal. The responder analysis and HbA1c levels did not change in either group. Mean (and standard deviation) fructosamine levels, before and after tea therapy, were significantly lower in the herbal tea group than in the placebo tea group (361 [98] versus 338 [100] micromol/L, p < 0.01 compared with 338 [60] versus 323 [49] micromol/L, p = 0.08). In the hyperglycemic subgroup the mean AUC during the meal challenge, before versus after tea therapy, was 776 (369) versus 639 (331) mmol/L (p = 0.22) in the herbal tea group and 433 (125) versus 420 (173) mmol/L (p = 0.90) in the placebo group. CONCLUSIONS: Although the responder analysis failed to show an effect of the herbal tea, the data suggest there may be a short-term benefit from the tea in subjects with poor glycemic control.

Aged↗