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Biomedical subjects

A Jones

Publications and source records attributed to A Jones.

At least 703 records · Page 39Linked to original sources
PubMedDate not supplied

Development of a competitive immunoassay for the determination of N-(2-hydroxypropyl)valine adducts in human haemoglobin and its application in biological monitoring.

Propylene oxide (PO) is an important industrial compound and a directly acting mutagen. Human exposure to PO can be monitored by the determination of haemoglobin adducts. An immunoassay that quantifies the N-terminal adduct N-(2-hydroxypropyl)valine in whole haemoglobin was developed and its potential usefulness as a tool for biologically monitoring occupational exposure was demonstrated. Analytical reliability was confirmed in a comparative study with GC-MS (range 3.7-992 nmol g-1 haemoglobin (Hb), correlation coefficient 0.99, n=10). The assay has been configured as a competitive enzyme-linked immunosorbent assay to facilitate the rapid throughput of samples. The assay employs a whole blood matrix and has a working range of 2-250 pmol g-1 Hb. It does not appear to be affected by structurally similar metabolites and has been used to determine adducts in human blood samples. The first results in potentially exposed workers indicate the assay's high potential usefulness in routine occupational biomonitoring of exposure to PO.

Animals↗
PubMedDate not supplied

Contamination of illicit phencyclidine with 1-piperidinocyclohexanecarbonitrile.

A retrospective study of illicit phencyclidine (PCP), which consisted of 94 different cases or 213 individual samples, has shown that one third of both the powder/tablets and green plant material contained the synthetic contaminant 1-piperidinocyclohexanecarbonitrile (PCC). The mole % PCC/PCP ranged from 1 to 68%. The method of analysis was gas chromatography (3% OV-7, 205 degrees C) and in preparation for analysis the sample was dissolved directly in chloroform or extracted from a strongly acidic solution (0.1 N HCl). Using these extraction conditions PCC was found not to undergo measurable decomposition.

Chromatography, Gas↗
PubMedDate not supplied

In situ neutralization in Boc-chemistry solid phase peptide synthesis. Rapid, high yield assembly of difficult sequences.

Simple, effective protocols have been developed for manual and machine-assisted Boc-chemistry solid phase peptide synthesis on polystyrene resins. These use in situ neutralization [i.e. neutralization simultaneous with coupling], high concentrations (> 0.2 M) of Boc-amino acid-OBt esters plus base for rapid coupling, 100% TFA for rapid Boc group removal, and a single short (30 s) DMF flow wash between deprotection/coupling and between coupling/deprotection. Single 10 min coupling times were used throughout. Overall cycle times were 15 min for manual and 19 min for machine-assisted synthesis (75 residues per day). No racemization was detected in the base-catalyzed coupling step. Several side reactions were studied, and eliminated. These included: pyrrolidonecarboxylic acid formation from Gln in hot TFA-DMF; chain-termination by reaction with excess HBTU; and, chain termination by acetylation (from HOAc in commercial Boc-amino acids). The in situ neutralization protocols gave a significant increase in the efficiency of chain assembly, especially for "difficult" sequences arising from sequence-dependent peptide chain aggregation in standard (neutralization prior to coupling) Boc-chemistry SPPS protocols or in Fmoc-chemistry SPPS. Reported syntheses include HIV-1 protease(1-50,Cys.amide), HIV-1 protease(53-99), and the full length HIV-1 protease(1-99).

Acetylation↗
PubMedDate not supplied

Efficacy and kinetics of carprofen, administered preoperatively or postoperatively, for the prevention of pain in dogs undergoing ovariohysterectomy.

OBJECTIVE: To determine what effect the timing of carprofen administration has on the severity of postoperative pain in dogs undergoing ovariohysterectomy and to investigate the pharmacokinetics of carprofen under these conditions. STUDY DESIGN: A prospective, randomized, double-blind, clinical trial. ANIMALS: Sixty-two adult bitches weighing between 10 and 25 kgs, undergoing elective ovariohysterectomy. METHODS: Examinations were performed for 20 hours postoperatively using subjective visual assessment scoring systems (DIVAS) and objective mechanical nociceptive threshold measurements. Forty dogs were assigned to one of three groups: (1) preoperative carprofen; (2) postoperative carprofen; and (3) no analgesics (saline injections). The dose of carprofen was 4.0 mg/kg subcutaneously. In another 22 bitches, the pharmacokinetics of carprofen given preoperatively or postoperatively at the same dose were examined. RESULTS: The dogs given carprofen preoperatively had lower pain scores than the other groups, significantly so at 2 hours postextubation (P < .01 and P < .05, Kruskal-Wallis and post hoc Dunn's). Mechanical pain thresholds measured at the distal tibia showed the development of hyperalgesia at 12 and 20 hours postextubation; this was prevented by both the preoperative (P < .05 at 12 and 20 hours, Kruskal-Wallis) and postoperative (P < .05 at 20 hours, Kruskal-Wallis) administration of carprofen. Mechanical pain threshold testing at the wound showed a significant analgesic effect of carprofen. Plasma concentrations of carprofen were not directly related to analgesia; maximum plasma concentration, the area under the curve to the last data point, and area under the first moment curve up to the last data point were all significantly higher in the dogs given carprofen postoperatively (P < .05, Mann-Whitney). CONCLUSION: Preoperative administration of carprofen has a greater analgesic effect than postoperative administration in the early postoperative period in dogs undergoing ovariohysterectomy. Plasma levels of carprofen are not related to the degree of analgesia achieved. CLINICAL RELEVANCE: Carprofen provides effective analgesia after canine ovariohysterectomy. The timing of analgesic administration is important to optimize the control of postoperative pain.

Animals↗
PubMedDate not supplied

Qualitative interview study of communication between parents and children about maternal breast cancer.

OBJECTIVE: To examine parents' communication with their children about the diagnosis and initial treatment of breast cancer in the mother. DESIGN: Qualitative interview study within cross sectional cohort. SETTING: Two breast cancer treatment centres. PARTICIPANTS: 32 women with stage I or stage II breast cancer with a total of 56 school aged children. MAIN OUTCOME MEASURES: Semistructured interview regarding timing and extent of communication with children about the diagnosis and initial treatment of the mother's illness, reasons for talking to children or withholding information, and help available and requested from health professionals. RESULTS: Women were most likely to begin talking to their children after their diagnosis had been confirmed by biopsy, but a minority waited until after surgery or said nothing at all. Family discussion did not necessarily include mention of cancer. There was considerable consistency in the reasons given for either discussing or not discussing the diagnosis. The most common reason for not communicating was avoidance of children's questions and particularly those about death. While most mothers experienced helpful discussion with a doctor concerning their illness, few were offered help with talking to children; many would have liked help, particularly the opportunity for both parents to talk to a health professional with experience in understanding and talking to children. CONCLUSIONS: Parents diagnosed with cancer or other serious illnesses should be offered help to think about whether, what, and how to tell their children and about what children can understand, especially as they may well be struggling themselves to come to terms with their illness.

Adult↗
PubMedDate not supplied

Ondansetron compared with granisetron in the prophylaxis of cisplatin-induced acute emesis: a multicentre double-blind, randomised, parallel-group study. The Ondansetron and Granisetron Emesis Study Group.

This is the first international, multi-centre, double-blind, randomised, parallel group study to directly compare the efficacy and safety profile of a single intravenous dose of ondansetron (8 or 32 mg) with granisetron (3 mg) in the control of cisplatin-induced acute emesis. A total of 496 patients were randomised to receive one of three anti-emetic treatments prior to cisplatin chemotherapy (> or = 50 mg/m2). Of these, 165 and 162 patients received 8 and 32 mg of ondansetron, respectively, and 169 patients received 3 mg of granisetron. Complete control of emesis (0 emetic episodes) over 24 h was reported in 59% of patients in the 8-mg ondansetron group, 51% of patients in the 32-mg ondansetron group and 56% of patients in the granisetron group. Complete or major control (< or = 2 emetic episodes) was achieved in 76 and 74% of patients in the 8- and 32-mg ondansetron group, respectively, compared with 78% of patients in the granisetron group. Nausea graded none or mild 24 h after the start of cisplatin infusion was reported in 71 and 69% of patients in the 8- and 32-mg ondansetron groups, respectively, and in 73% of patients in the granisetron group. There were no significant differences between the treatment groups when global satisfaction scores were compared. Logistic regression models were fitted to assess any interaction between treatments and prognostic factors (age, gender, alcohol use, cisplatin dose or concomitant chemotherapy) on complete or major response, but there was no evidence of interaction for any factor. All three anti-emetic treatments were well tolerated and no severe or unexpected drug-related adverse events were observed with ondansetron or granisetron. Headache, the most reported drug-related adverse event for all three treatment groups, occurred in 9% of all patients. In summary, no significant difference was observed between any of the treatment groups with respect to emesis, nausea or drug-related adverse events.

Adult↗
PubMedDate not supplied

Extracranial carotid arterial disease in patients with familial hypercholesterolemia and coronary artery disease treated with colestipol and nicotinic acid.

Carotid bifurcation atherosclerosis was demonstrated in 34 of 108 patients with familial hypercholesterolemia and coronary artery disease by B-scan, continuous-wave Doppler sonography, and intravenous digital subtraction angiography. An intensive combined therapy of diet, colestipol, and nicotinic acid was mounted to control the hypercholesterolemia of these patients. Their serial sonographies and digital subtraction angiography were evaluated independently by technical specialists who served as coinvestigators. The data obtained suggest that extracranial arterial disease can develop concurrently with coronary artery disease in a significant proportion of patients with familial hypercholesterolemia, and amaurosis fugax, transient ischemic attack, cerebral infarction, and myocardial infarction did not recur during 58-72 months of control of familial hypercholesterolemia in this series of patients.

Adult↗
PubMedDate not supplied

Effect of resistance training on lumbar extension strength.

Development of a new testing machine, which stabilizes the pelvis, allowed us to evaluate the lumbar extensor muscles before and after training. Fifteen healthy subjects (29.1 +/- 8 years of age) trained 1 day per week for 10 weeks and 10 healthy subjects (33.7 +/- 16 years of age) acted as controls. Training consisted of 6 to 15 repetitions of full range of motion variable resistance lumbar extension exercise to volitional fatigue and periodic maximal isometric contractions taken at seven angles through a full range of motion. Before and after the 10 week training period, subjects completed a maximum isometric strength test at seven angles through a 72 degrees range of motion (0 degrees, 12 degrees, 24 degrees, 36 degrees, 48 degrees, 60 degrees, and 72 degrees of lumbar flexion). The training group significantly improved in lumbar extension strength at all angles (P less than or equal to 0.01). The result at 0 degrees (full extension) showed an increase from 180.0 +/- 25 Nm to 364.1 +/- 43 Nm (+102%) and at 72 degrees (full flexion) from 427.4 +/- 44.1 to 607.4 +/- 68 (+42%) Nm. Results from the control group showed no change (P greater than or equal to 0.05). The magnitude of gain shown by the training group reflects the low initial trained state of the lumbar extensor muscles. These data indicate that when the lumbar area is isolated through pelvic stabilization, the isolated lumbar extensor muscles show an abnormally large potential for strength increase.

Adult↗
PubMedDate not supplied

A biomechanical evaluation of the iliotibial tract screw tenodesis.

Biomechanical testing of the iliotibial tract screw tenodesis was performed in 10 cadaveric knees under forces approximating in vivo conditions. Force versus displacement curves at various flexion angles were generated with the anterior cruciate ligament intact, with the anterior cruciate ligament sectioned, and after the iliotibial tract screw tenodesis had been performed. Displacement force was measured to 5, 10, and 15 mm. The iliotibial tract screw tenodesis was ineffective in reducing anterior translation of the tibia in the anterior cruciate ligament-deficient knee at forces approximating in vivo conditions.

Aged↗
PubMedDate not supplied

Family therapy: approaches to treatment.

Family therapy deals with the way that people in family groups relate to one another. In their interactions with families, nurses may be confronted with an array of therapeutic techniques. This article aims to provide a brief account of three major conceptual models of family therapy treatment.

Adult↗
PubMedDate not supplied

How effective is reality orientation for elderly, confused patients?

Nurses still use reality orientation as a form of therapy, with care plans still discussing orientation in terms of time, place and person. This article aims to explore and review selected studies in an attempt to quantify the effects, if any, and concludes with relevant ethical considerations inherent within the technique.

Age Factors↗
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The value of Peplau's theory for mental health nursing.

Recent changes in mental health care have necessitated reevaluation of Peplau's nursing theory. There is an expanding body of nursing knowledge and a debate is taking place regarding the difference between models and theories. Peplau's theory considers nursing as an interpersonal process between nurse and patient. The theory lacks empirical investigation and is not yet tested regarding the multidisciplinary team approach, which is largely based on the medical model. For the theory to gain credibility within the dynamics of the multidisciplinary team, it must be tested within a framework of robust research design involving various diagnostic groups and practice settings. Until such time, the theory's utility must seriously be questioned within contemporary mental health practice.

Humans↗
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Managed care strategy for mental health services.

In the UK, managed care is beginning to be recognized as a cost effective, quality-driven system which can be used to structure patient care. This article examines the potential use of managed care pathways in mental health services, focusing on clients with schizophrenia. The strengths of managed care include the effective coordination of healthcare resources, the clear accountable audit of mental health practice and the re-engineering of mental health practice to improve patient outcomes. Problems in designing representative care pathways and encouraging healthcare providers to implement care pathways are some of the disadvantages of this system.

Cost-Benefit Analysis↗
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Outreach interventions for the homeless mentally ill.

There has been a steady rise in the number of homeless mentally ill in Britain. This article reviews the scale of the problem and identifies the need for change within mental health services in order to address this challenge. It is argued that mainstream psychiatric services need to become more diverse and open in their approach to this potentially isolated group of users. The authors suggest that this could be achieved by embracing assertive outreach interventions. Innovative projects using a range of care providers, including voluntary workers, past users of the service and professional mental health workers, are discussed as an alternative framework to traditional services. In conclusion, the article highlights some of the professional and social implications for psychiatric nurses and mental health practice.

Community Mental Health Services↗
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The development of mental health care pathways: friend or foe?

Greater emphasis is being placed on mental health services to be more responsive to clinical variation. Care pathways can standardize clinician response to established diagnostic groups such as schizophrenia. This article discusses care pathways using the findings of a research study carried out in London to explore the development and implementation of a care pathway. Respondents encountered many difficulties such as the principles behind individualized care and generic roles and responsibilities in preformulating their work into a care pathway sequence. This article concludes with areas for further application and research.

Attitude of Health Personnel↗
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Causes and effects of chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is a chronic, slowly progressive disease which is a significant cause of disability and death (British Thoracic Society (BTS), 1997). Despite the clinical and economic burden it creates, it is a relatively poorly understood disease, with many of those with COPD being undiagnosed. This article will discuss some of the causes and effects of COPD and give particular consideration to its impact on patients. It will also consider how the impact of the disease may be reduced, giving greater attention to two specific interventions, namely pulmonary rehabilitation and smoking cessation. The BTS guidelines as a framework for the management of COPD, and the need for a collaborative approach between primary and secondary care, will also be highlighted.

Breathing Exercises↗