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J Jenkins

Publications and source records attributed to J Jenkins.

At least 73 records · Page 4Linked to original sources
PubMed1998

Field activity cost estimates for the first 3 years of the World Bank Loan Project for schistosomiasis control in China.

The World Bank Loan Project for schistosomiasis in China commenced field activities in 1992. In this paper, we describe disease control strategies for levels of different endemicity, and estimate unit costs and total expenditure of screening, treatment (cattle and humans) and snail control for 8 provinces where Schistosoma japonicum infection is endemic. Overall, we estimate that more than 21 million US dollars were spent on field activities during the first three years of the project. Mollusciciding (43% of the total expenditure) and screening (28% of the total) are estimated to have the most expensive field activities. However, despite the expense of screening, a simple model predicts that selective chemotherapy could have been cheaper than mass chemotherapy in areas where infection prevalence was higher than 15%, which was the threshold for mass chemotherapy intervention. It is concluded that considerable cost savings could be made in the future by narrowing the scope of snail control activities, redefining the threshold infection prevalence for mass chemotherapy, defining smaller administrative units, and developing rapid assessment tools.

Animals↗
PubMed1998

Causes of staff abuse in health care facilities. Implications for prevention.

Verbal and physical abuse of health care workers (HCWs) is prevalent and costly. A 3 month prospective study was conducted to characterize precipitating conditions and the perpetrators of abusive incidents reported by HCWs at a large inner city hospital. Sixty-six HCWs reporting 102 incidents were interviewed by a research nurse within 48 hours of the incident. Abusive incidents resulted from 55 different patients and 11 visitors. Verbal abuse accounted for 42 incidents (41%) and 60 (59%) involved physical abuse. Two thirds of the abuse occurred on psychiatric wards, 20% on inpatient wards, and 13% in other settings. Overall, twice as many abusive incidents were inflicted by males as females. Cognitive impairment accounted for 19% of the incidents and one abuser was intoxicated at the time. Rule enforcement precipitated abuse in 70% of incidents. Researchers concluded that reviewing rules that apply to patients, how HCWs are trained to enforce rules, how to respond when service requested cannot be provided promptly, and how HCWs can protect themselves when performing a service were important elements in the prevention of staff abuse.

Causality↗
PubMed1997

Two crystal structures of pectin lyase A from Aspergillus reveal a pH driven conformational change and striking divergence in the substrate-binding clefts of pectin and pectate lyases.

BACKGROUND: Microbial pectin and pectate lyases are virulence factors that degrade the pectic components of the plant cell wall. The homogalacturan backbone of pectin varies in its degree of methylation from the highly methylated and relatively hydrophobic form known as pectin, to the fully demethylated and highly charged form known as pectate. Methylated and demethylated regions of pectin are cleaved by pectin lyase and calcium-dependent pectate lyases, respectively. Protein engineering of lyases specific for particular patterns of methylation, will yield modified pectins of high value to the food and pharmaceutical industries. RESULTS: The crystal structures of pectin lyase A from two strains of Aspergillus niger, N400 and 4M-147, have been determined at pH 6.5 (2.4 A resolution) and pH 8.5 (1.93 A resolution), respectively. The structures were determined by a combination of molecular replacement, multiple isomorphous replacement and intercrystal averaging. Pectin lyase A folds into a parallel beta helix and shares many of the structural features of pectate lyases, despite no more than 17% sequence identity after pairwise structure-based alignment. These shared structural features include amino acid stacks and the asparagine ladder. However, the differences in the substrate-binding clefts of these two enzymes are striking. In pectin lyase A, the cleft is dominated by aromatic residues and is enveloped by negative electrostatic potential. In pectate lyases, this cleft is rich in charged residues and contains an elongated ribbon of positive potential when Ca2+ is bound. The major difference between the two pectin lyase A structures from the two strains is in the conformation of the loop formed by residues 182-187. These observed differences are due to the different pH values of crystallization. CONCLUSIONS: The substrate-binding clefts and catalytic machinery of pectin and pectate lyases have diverged significantly. Specificity is dictated by both the nature of the protein-carbohydrate interaction and long-range electrostatic forces. Three potential catalytic residues have been identified in pectin lyase, two of these are common to pectate lyases. Pectin lyase A does not bind Ca2+ but an arginine residue is found in an equivalent position to the Ca2+ ion in pectate lyase, suggesting a similar role in catalysis. The activity of pectin lyase A is pH -dependent with an optimum activity at pH 5.5. The activity drops above pH 7.0 due to a conformational change at the binding cleft, triggered by the proximity of two buried aspartate residues.

Aspergillus niger↗
PubMed1997

An assessment of the distortion of arteries due to sectioning in endomyocardial biopsies.

Arteries are usually studied morphometrically after pressurized fixation and resin embedding. These procedures are impracticable when dealing with diagnostic biopsies. The accuracy of arterial morphometry is determined partly by the degree of tissue distortion during section preparation. The axial ratios of 7340 arteries were measured in 353 endomyocardial biopsies from 23 patients and then compared with those expected from mathematical modelling. An excess of elliptical arteries was found. The distribution of orientation of the long axes of these best fitted a simulated 10 per cent linear distortion in the direction of microtomy. In conclusion, these results suggest that although there is some tissue distortion during sectioning, useful data may be obtained from morphometry of arteries in routinely processed endomyocardial biopsies.

Biopsy↗
PubMed1997

Three-dimensional reconstruction of abnormal intramural coronary arteries in human cardiac allograft biopsies.

A novel abnormality of intramural coronary arteries has been recently described in allograft cardiac biopsies. Three-dimensional (3-D) models of these abnormal arteries have now been constructed from serial histological sections of diagnostic post-transplant endomyocardial biopsies. These revealed that there was an interlacing meshwork of longitudinal smooth muscle bundles in abnormal arteries. In addition, the lumen and external surface of these arteries were irregular. This contrasted with reconstructions of normal control arteries in the same sections, which were smooth and straight. This elucidation of an unusual abnormality suggests that 3-D reconstruction of arteries in forceps biopsies may be a useful technique.

Biopsy↗
PubMed1997

Educational issues related to cancer genetics.

OBJECTIVES: To discuss educational issues facing the nurse and to review opportunities for genetic education. DATA SOURCES: Published articles pertaining to cancer genetics and nursing. CONCLUSIONS: Health care providers are experiencing significant changes in their professional lives. Not only is the environment where services are provided changing, but the need for consumers to be knowledgeable and the expectations of care providers are enhanced. One significant challenge is the genetic discoveries influencing available health care. Educational preparation is crucial to the application of genetic technology in practice, research, and management of all patients. IMPLICATIONS FOR PRACTICE: The science and technology of genetics offers tremendous potential change for health care delivery. This in turn requires knowledgeable nurses to provide total patient care through the integration of genetic information. Determination of preferred methods, content, access, and evaluation is the focus of genetic educational issues.

Computer Communication Networks↗
PubMed1997

Helical computed tomography in the assessment of abdominal aortic pathology.

A pilot study was undertaken to evaluate the role of helical computed tomography in the assessment of abdominal aortic pathology. A total of 17 patients underwent intra-arterial digital subtraction of angiography (IADSA) and helical computed tomography, with eight patients undergoing subsequent operative intervention. A comparison of radiological findings between IADSA and helical computed tomography (CT) was made and, where applicable, a comparison was made with operative findings. Pathology included abdominal aortic aneurysm (AAA) (n = 12), thoraco-abdominal aneurysm (n = 2) and dissection (n = 1), graft distension following AAA repair (n = 1) and plaque haemorrhage in the distal aorta following percutaneous transluminal angioplasty (PTA) of the iliac artery (n = 1). Planned operative management as based on pre-operative helical CT imaging findings, in particular with reference to the type of graft used (straight or bifurcated) was not changed at operation. Our findings on helical CT in regards to AAA, thoroco-abdominal aneurysm and dissection correlated well with angiography and surgery findings.

Aged↗
PubMed1997

Pyrimethamine-resistant Plasmodium falciparum parasites among Tanzanian children: a facility-based study using the polymerase chain reaction.

A mutation-specific polymerase chain reaction method was used to estimate the proportion of pyrimethamine-resistant parasites in 101 children reporting with malaria at the hospital in Ifakara, a town in southern Tanzania. The method is based on the observation that a point mutation (Asn-108) in the dihydroifolate reductase gene confers resistance to pyrimethamine. Twenty-eight percent of the examined 101 children had pyrimethamine-resistant parasites, 65% had pyrimethamine-sensitive parasites with the wild-type Ser-108 codon, and 9% had both alleles, suggesting a mixed infection. None of the 21 children with clinical malaria had pyrimethamine-resistant parasites. Currently, sulfadoxine-pyrimethamine is considered a potential first-line drug for malaria treatment in most African countries. We suggest that although sulfadoxine-pyrimethamine could still be effective against chloroquine-resistant malaria in this area, its judicious use is important so as to minimize the spread of resistance.

Animals↗
PubMed1996

Crystallization and preliminary X-ray analysis of pectin lyase A from Aspergillus niger.

The major secreted pectin lyase (E.C. 4.2.2.10) from Aspergillus niger, strain 4M-147, has been purified and crystallized by the hanging-drop method using polyethylene glycol as precipitant. The crystals belong to the space group P2(1)2(1)2(1) with cell dimensions a = 45.2, b = 83.2, c = 93.1 A (1 A = 0.1 nm) and a single molecule in the asymmetric unit. The crystals diffract to at least 2.0 A resolution and are suitable for structure determination.

Journal Article↗
PubMed1996

Bilingual hearing acquisition in Welsh and English following cochlear implantation.

A post lingually deafened adult equilingual in Welsh and English, receive rehabilitation in both languages following cochlear implantation. Hearing acquisition was very similar in both languages, indicating that there is no need to vary the electrode coding strategy for different languages of Indo-European origin. The situation may be difficult for tonal languages such as Chinese.

Cochlear Implants↗
PubMed1996

Tolerance of mixed lipid emulsion in neonates: effect of concentration.

AIMS: To compare the effect of concentration of a mixed lipid emulsion (50:50 medium chain triglyceride/long chain triglyceride) (MCT/LCT) on lipid tolerance in neonates. METHODS: A prospective randomised controlled trial of 75 neonates requiring prolonged parenteral nutrition was conducted in the neonatal intensive care units of the Royal Maternity Hospital, Belfast, and the Waveney Hospital, Ballymena. Thirty eight infants received 10% and 37 20% lipid emulsion. Infants were randomly assigned to groups at the start of parenteral nutrition and studied if they required seven or more days of this. Lipid tolerance was assessed by twice weekly measurements of plasma triglyceride and cholesterol concentrations and weekly measurement of non-esterified fatty acids and beta hydroxy butyrate. Anthropometry was carried out weekly. RESULTS: The mean cholesterol in the 10% group was significantly higher within the first seven days of the study compared with the 20% group (3.5 vs 2.87 mmol/l), and continued to rise over the study period in contrast to the 20% group. A similar pattern was observed with the triglyceride concentrations. There was no significant difference in non-esterified fatty acids, beta hydroxy butyrate, or growth between the two groups. CONCLUSION: Sick neonates show better biochemical tolerance to 20% MCT/LCT emulsion than to 10% emulsion.

Cholesterol↗
PubMed1996

Systems energetics: holistic model for advanced practice nursing.

The advanced practice nurse is faced with constant and unrelenting change. Learning ways to not only view change as healthy, but also incorporate this into practice every day can be very difficult. Systems Energetics is a holistic, natural health model. Working with nature's natural cycles, your body and common sense, Systems Energetics helps balance kinetic and potential energy in healthy, life-fulfilling ways.

Holistic Nursing↗