Australian primary health care nurses

Preconception care (PCC) entails counselling and interventions to optimise health before pregnancy. Barriers to this service delivery include access and time. Primary healthcare nurses (PHCNs) are uniquely placed to deliver PCC. The aim of this study was to understand PHCNs' knowledge, practice and attitudes to PCC. A cross-sectional study was performed of a convenience sample of PHCNs in Australia who were seeing people of reproductive age. Recruitment was via the Australian Primary Health Care Nurses Association (APNA) electronic communication platforms. The 18-item, online, anonymous survey captured demographics, as well as PCC knowledge, practices and attitudes. Descriptive statistics were used to describe our findings. In all, 152 completed surveys were received. Of all respondents, 74% stated they discuss PCC in their practice, although only 13% do so routinely. Of these, more preconception discussions are held with women than with men. In total, 95% of respondents identified at least one barrier to delivery of PCC, with lack of time and knowledge being the most common. The findings of this study can inform targeted strategies, including education programs and resources, and consideration of incentives to support PHCNs deliver PCC. This study identifies areas for improvement at the individual, organisational and health system levels to enhance the role of PHCNs in PCC.

The relationships among knowledge, self-efficacy, preparedness, decisional conflict, and decisions to participate in a cancer clinical trial

BACKGROUND

Cancer clinical trials (CCTs) are important tools in the development of improved cancer therapies; yet, participation is low. Key psychosocial barriers exist that appear to impact a patient's decision to participate. Little is known about the relationship among knowledge, self-efficacy, preparation, decisional conflict, and patient decisions to take part in CCTs.

OBJECTIVE

The purpose of this study was to determine if preparation for consideration of a CCT as a treatment option mediates the relationship between knowledge, self-efficacy, and decisional conflict. We also explored whether lower levels of decisional conflict are associated with greater likelihood of CCT enrollment.

METHOD

In a pre-post test intervention study, cancer patients (N = 105) were recruited before their initial consultation with a medical oncologist. A brief educational intervention was provided for all patients. Patient self-report survey responses assessed knowledge, self-efficacy, preparation for clinical trial participation, decisional conflict, and clinical trial participation.

RESULTS

Preparation was found to mediate the relationship between self-efficacy and decisional conflict (p = 0.003 for a test of the indirect mediational pathway for the decisional conflict total score). Preparation had a more limited role in mediating the effect of knowledge on decisional conflict. Further, preliminary evidence indicated that reduced decisional conflict was associated with increased clinical trial enrollment (p = 0.049).

CONCLUSIONS

When patients feel greater CCT self-efficacy and have more knowledge, they feel more prepared to make a CCT decision. Reduced decisional conflict, in turn, is associated with the decision to enroll in a clinical trial. Our results suggest that preparation for decision-making should be a target of future interventions to improve participation in CCTs.

Results from phase Ib studies of PX-12, a thioredoxin inhibitor in patients with advanced solid malignancies

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Background: PX-12, a small-molecule inhibitor of Thioredoxin-1 (Trx-1) stimulates apoptosis, down-regulates HIF- 1α, VEGF in animal models. High levels of Trx-1 have been linked to chemoresistance in lung cancers. The phase 2 dose of PX-12 was 226 mg/m2 given by 3-h infusion IV x 5 days, q 21d (Ramanathan RK et al. CCR 13; 2109; 2007). Two Phase 1b trials of PX-12 in patients with advanced solid tumors have been completed to determine the safety, tolerability and optimal biologic dose when delivered by prolonged infusion. Methods: PX-12 was administered as a 24-h infusion every q7- 14d starting at 150 mg/m2/day (n=18); or a 72-h infusion q 21d, starting at 300 mg/m2/day (n=14) using a portable delivery pump. Results: Both the 24- or 72-h infusion of PX-12 were well tolerated in patients at doses up to 400 mg/m2/day. Common grade 1/2 AE's included fatigue, taste alteration, and odor caused by expired drug metabolite. In the 24 h study the maximal dose evaluated was 450 mg/m2. No DLTs were observed in this study. Since no MTD was reached on 24-h infusion up to 450 mg/m2 dose level, additional higher doses were explored utilizing 72-h infusion. DLT in the 72-h study at the highest dose administered (500 mg/m2/day) included reversible hypoxia with or without pneumonitis. Best response was stable disease in 3 pts (SD): liver cancer and colon cancer (24-h infusion) and rectal cancer (72-h infusion). Pharmacodynamics (PD): PX- 12 lowered circulating Trx-1 levels in patients who had starting Trx-1 levels 3-fold greater than that of the normal population (5.4 ng/mL) including all three SD. Circulating VEGF and FGF-2 levels were also lowered over multiple courses of treatment in these patients. The pharmacokinetics of PX-12 showed a dose dependent increase of Cmax and no accumulation over multiple cycles following a 24 h infusion. Conclusions: Dosing at 400 mg/m2/day appears safe and tolerable as a 24–72-h infusion. Extending the infusion time to 72h appears to decrease the intensity of cough and odor compared to bolus 1–3 h infusion. The PD effect produced by PX-12 was apparent only in those patients with elevated plasma Trx-1 levels. Patients with elevated TRX-1 levels appear to have the best probability of having SD. Supported by ProlX Pharmaceuticals/Oncothyreon through an award from the NCI.

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Expression of cysteine dioxygenase (EC 1.13.11.20) and sulfite oxidase in the human lung: a potential role for sulfate production in the protection from airborne xenobiotica

AIMS

The lung is one of the major sites of phase I cytochrome P450 enzyme and phase II sulfotransferase expression, which together are thought to act as an enzymic barrier against the unimpeded transfer of airborne xenobiotics into the lung parenchyma and systemic circulation. Sulfate for conjugation is produced primarily from the oxidation of cysteine, begun by cysteine dioxygenase (CDO), and completed with the conversion of sulfite to sulfate via sulfite oxidase (SO). Little is known about the site of expression of these two enzymes in the alveoli of the human lung.

METHODS

Antibodies and oligonucleotide probes raised against both CDO and SO were used for immunohistochemistry and in situ hybridisation, respectively, to investigate the expression of CDO and SO in human lung alveoli.

RESULTS

CDO and SO were expressed in alveolar epithelial cells, which is also the site of expression of cytochrome P450 1B1.

CONCLUSIONS

These results demonstrate that the two key enzymes in sulfate production are expressed in the same locale as phase I and phase II enzymes, and that these two enzymes may be involved in the production of sulfate for the maintenance of a metabolic barrier against the entry of airborne xenobiotics and the synthesis of important structural proteins and proteoglycans.

A dose-ranging study to evaluate the antiretroviral activity and safety of amprenavir alone and in combination with abacavir in HIV-infected adults with limited antiretroviral experience

OBJECTIVE

To evaluate the antiretroviral activity and safety of multiple escalating doses of amprenavir administered alone, and in combination with abacavir in HIV-1-infected adults.

DESIGN

Sixty-two HIV-1-infected subjects were enrolled in a multicentre, open-label, non-randomized, dose-escalating trial.

METHODS

Subjects were assigned to one of six dose groups and received amprenavir 300 mg twice daily, 300 mg three times daily, 900, 1050, or 1,200 mg twice daily for 4 weeks. One dose group received amprenavir 900 mg twice daily in combination with abacavir 300 mg twice daily for 4 weeks. Antiretroviral activity was assessed by measuring changes from baseline in plasma HIV-1 RNA levels and CD4 cell counts. Safety was evaluated by monitoring clinical adverse events and changes in laboratory values. Genotypic and phenotypic analyses were performed using ABI sequencing and the recombinant virus assay, respectively.

RESULTS

At week 4, amprenavir monotherapy (900, 1,050, or 1,200 mg twice daily) resulted in marked decreases in plasma HIV-1 RNA levels (1.3-1.6 log10 copies/ml), and substantial increases in CD4 cell counts in the two dose groups who received 1,050 mg twice daily (118 x 10(6) cells/mm3) or 1,200 mg twice daily (114 x 10(6) cells/mm3). Amprenavir/abacavir resulted in median plasma HIV-1 RNA reductions of 1.8 log10 copies/ml, and median CD4 cell count increases of 138 x 10(6) cells/mm3. Amprenavir was reasonably well tolerated with few treatment-limiting adverse events. No known active site mutations associated with amprenavir resistance were selected in any of the dose groups, and no significant phenotypic resistance to amprenavir developed during 4 weeks of therapy.

CONCLUSIONS

The antiviral effect of amprenavir monotherapy increased with escalating doses, and all amprenavir doses were reasonably well tolerated over 4 weeks of therapy. Amprenavir/abacavir combination therapy elicited a potent antiviral effect. The three highest doses of amprenavir (900, 1,050 and 1,200 mg twice daily) were selected to design subsequent Phase II and III studies that confirmed the safety profile and efficacy of amprenavir in combination regimens and led to the approval of amprenavir in the USA in 1999.

A phase II trial of dual protease inhibitor therapy: amprenavir in combination with indinavir, nelfinavir, or saquinavir

This study evaluated dual protease inhibitor (PI) regimens containing amprenavir (APV) in PI-naive, HIV-1-infected patients over 48 weeks. Patients were randomized to 800-mg APV combined with 800-mg indinavir (IDV), 750-mg nelfinavir (NFV), or 800-mg saquinavir-soft gel capsule (SGV-SGC), all three times daily without nucleoside reverse transcriptase inhibitors, or APV given alone for 3 weeks and then with 150-mg lamivudine (3TC) and 300-mg zidovudine (ZDV), twice daily. Dual PI therapy demonstrated substantial antiviral activity and was generally safe and well tolerated. Eight patients had virologic failure; 5 were receiving dual PI therapy and 3 were in the APV/3TC/ZDV arm. The protease I50V mutation characteristic of APV resistance was not observed, although other key PI mutations were selected in 4 patients failing therapy, 2 of whom had PI resistance at baseline.

Avanti 3: A Randomized, Double-Blind Trial to Compare the Efficacy and Safety of Lamivudine plus Zidovudine versus Lamivudine plus Zidovudine plus Nelfinavir in HIV-1-Infected Antiretroviral-Naive Patients

The objective of our randomized, multicentre, double-blind, placebo-controlled study was to investigate the safety, tolerability, and antiretroviral and immunological effect of double and triple combination therapy regimens. A total of 105 antiretroviral therapy-naive patients were randomized to receive either zidovudine (300 mg twice per day) plus lamivudine (150 mg twice per day) plus nelfinavir placebo (three times per day) ( n=52), or zidovudine/lamivudine (dose as before) plus nelfinavir (750 mg three times per day) ( n=53) for 28 weeks. After this time, patients were allowed to switch to open-label zidovudine/lamivudine/nelfinavir. The overall log10 reduction from baseline in plasma HIV-1 RNA was significantly greater in the zidovudine/lamivudine/nelfinavir group than the zidovudine/lamivudine group ( P=0.001; median treatment difference, –1.01 log10 copies/ml; 95% confidence interval –1.23 to –0.79), as measured by the average area under the curve minus baseline over 28weeks. Increases from baseline in CD4 cell counts were statistically significantly greater in the zidovudine/lamivudine/nelfinavir group (101.5 cells/ml) than the zidovudine/lamivudine group (47.0 cells/ml; P=0.027) at week 28.

Of note, the addition of nelfinavir from weeks 28–52 led to an increase in the proportion of subjects with plasma HIV-1 RNA <400 copies/ml from 17% (9/52 patients on zidovudine/lamivudine) to 50% (13/26 patients who switched to zidovudine/lamivudine/nelfinavir). Incidence of drug-related adverse events was similar in the two groups, except for nausea (more common in zidovudine/lamivudine group; 40 versus 17%) and diarrhoea (more common in zidovudine/lamivudine/nelfinavir group; 45 versus 14%). In conclusion, our study confirms the efficacy of triple combination therapy with two nucleoside analogues and a protease inhibitor compared with double-nucleoside therapy. Interestingly, the addition of nelfinavir to zidovudine/lamivudine, even after 6 months of double nucleoside therapy, led to a substantial virological benefit that was sustained over 24weeks in a subset of patients.

Safety profile and tolerability of amprenavir in the treatment of adult and pediatric patients with HIV infection

BACKGROUND

Amprenavir (APV) is a new HIV-I protease inhibitor used in combination with other antiretroviral agents for the treatment of HIV-1 infection.

OBJECTIVE

The aim of this study was to assess the safety profile and tolerability of APV.

METHODS

A review of data from 358 adults enrolled in 2 phase III, randomized, 48-week, controlled studies and from 268 children enrolled in 1 phase II and 1 phase III study was conducted. The adult data were collected between February 25, 1997, and April 1, 1999. Data were collected in children from September 10, 1997, to January 15, 1999; these data were collected before completion of either study. Adults and children who had and had not been treated previously with antiretroviral agents were enrolled. In these studies, APV was used in combination with 2 nucleoside reverse transcriptase inhibitors.

RESULTS

The most common drug-related adverse events in patients receiving APV were gastrointestinal events and oral/perioral paresthesia. The majority of adverse events were mild or moderate in intensity, early in onset, and transient. Nausea (27/358 patients, 8%), vomiting (15/358, 4%), rash (11/358, 3%), and diarrhea/loose stools (9/358, 3%) were the most common adverse events associated with treatment discontinuation. Severe laboratory abnormalities possibly related to APV were rare. In children, the nature and frequency of adverse events were similar to those in adults. Metabolic complications were infrequent in APV studies to date; symptoms related to fat redistribution were reported in <3% of patients treated with APV. Lipid or glucose laboratory abnormalities were reported with similar frequency in the APV and control groups in both studies in adults.

CONCLUSIONS

In the clinical trials reviewed, APV was generally well tolerated when administered with other antiretroviral agents in adult and pediatric patients with HIV infection.

In vivo assessment of trabecular bone structure using fractal analysis of distal radius radiographs

Our purpose in this study was (i) to measure trabecular bone structure using fractal analysis of distal radius radiographs in subjects with and without osteoporotic hip fractures, and (ii) to compare these measures with bone mineral density (BMD) as well as with measures of trabecular bone structure derived from high resolution magnetic resonance (MR) images. Distal radius radiographs were obtained using semi-industrial films (55 kVp, 400 mAs) in 30 postmenopausal patients, who had suffered osteoporotic hip fractures (74.8+/-8.2 years) in the last 24 months and 27 postmenopausal age-matched (74.6+/-6.6 yr) normal volunteers. Radiographs were digitized at 50 microm. A Fourier power spectrum-based fractal dimension (FD) characterizing the trabecular pattern was measured in a region of interest proximal to the joint line. The fractal dimension was calculated over two spatial frequency (f) ranges: FD1 was calculated over 0.5<log(f)<l.0, FD2 over the higher range 1.0<log(f)<1.5. Trabecular BMD in the radius was obtained using peripheral quantitative computed tomography (pQCT) (Stratec GmbH, Germany). In addition BMD of the proximal femur was determined using dual x-ray absorptiometry (DXA) (QDR 2000, Hologic, MA). In a subset of patients (16 controls and 18 with hip fractures), high resolution MR imaging of the distal radius (spatial resolution of 156 x 156 x 500 microm) was used to obtain measures analogous to bone histomorphometry. There were significant differences (p<0.05) between the fracture and nonfracture groups in the total femur BMD (13%), trabecular BMD in the distal radius (4%), and the fractal dimension in the radiographs (FD2) (3%). The correlations between FD2 and the total femur BMD as well as trabecular bone BMD in the distal radius were -0.48 (p<0.006) and -0.22 (p<0.33); respectively; FD1 increased with BMD and showed lower correlations. FD2 showed good correlations with App. Tb.N (-0.71) and App. Tb.Sp (0.69) (p<0.01), moderate correlation with App BV/TV (-0.53) (p<0.05), and no significant correlation with App. Tb.Th. The correlations between structural measures and FD1 showed the inverse trend and were typically lower. The odds ratios for a hip fracture were 2.44 for total femur BMD, 1.5 for trabecular BMD (radius), and 1.5 for FD2, respectively. In summary, the fractal measures derived from radiographs of the radius show differences between subjects with and without hip fractures, the predictive power of measures in the distal radius are comparable to radial trabecular BMD but lower than that of total hip BMD.

Fractal analysis of radiographs: assessment of trabecular bone structure and prediction of elastic modulus and strength

The purpose of this study was to determine whether fractal dimension of radiographs provide measures of trabecular bone structure which correlate with bone mineral density (BMD) and bone biomechanics, and whether these relationships depend on the technique used to calculate the fractal dimension. Eighty seven cubic specimen of human trabecular bone were obtained from the vertebrae and femur. The cubes were radiographed along all three orientations--superior-inferior (SI), medial-lateral (ML), and anterior-posterior (AP), digitized, corrected for background variations, and fractal based techniques were applied to quantify trabecular structure. Three different techniques namely, semivariance, surface area, and power spectral methods were used. The specimens were tested in compression along three orientations and the Young's modulus (YM) was determined. Compressive strength was measured along the SI direction. Quantitative computed tomography was used to measure trabecular BMD. High-resolution magnetic-resonance images were used to obtain three-dimensional measures of trabecular architecture such as the apparent bone volume fraction, trabecular thickness, spacing, and number. The measures of trabecular structure computed in the different directions showed significant differences (p<0.05). The correlation between BMD, YM, strength, and the fractal dimension were direction and technique dependent. The trends of variation of the fractal dimension with BMD and biomechanical properties also depended on the technique and the range of resolutions over which the data was analyzed. The fractal dimension showed varying trends with bone mineral density changes, and these trends also depended on the range of frequencies over which the fractal dimension was measured. For example, using the power spectral method the fractal dimension increased with BMD when computed over a lower range of spatial frequencies and decreased for higher ranges. However, for the surface area technique the fractal dimension increased with increasing BMD. Fractal measures showed better correlation with trabecular spacing and number, compared to trabecular thickness. In a multivariate regression model inclusion of some of the fractal measures in addition to BMD improved the prediction of strength and elastic modulus. Thus, fractal based texture analysis of radiographs are technique dependent, but may be used to quantify trabecular structure and have a potentially valuable impact in the study of osteoporosis.

Formulation and in vivo evaluation of ocular insert containing phenylephrine and tropicamide

A Gelfoam based ocular device containing 1.7 mg of phenylephrine and 0.6 mg of tropicamide was formulated and evaluated for pupillary dilation in rabbits. The manufacturing procedure is fairly simple and the required excipients are inexpensive. The in vivo results show that the mydriatic response produced by the proposed device is larger and longer lasting than that produced by eyedrops with an equivalent amount of phenylephrine and tropicamide. The results reported in this study, along with those of previous studies, imply that Gelfoam(R) is a versatile drug carrier for either local or systemic drug delivery via the ophthalmic route.

Closed contour edge detection of blood vessel lumen and outer wall boundaries in black-blood MR images

Quantitative measurements of the blood vessel wall area may provide useful information of atherosclerotic plaque burden, progression and/or regression. Magnetic resonance imaging is a promising technique for identifying both luminal and outer wall boundaries of the human blood vessels. Currently these boundaries are primarily defined manually, a process viewed as labor intensive and subject to significant operator bias. Fully automated post-processing techniques used for identifying the lumen and wall boundaries, on the other hand, are also problematic due to the complexity of signal features in the vicinity of the blood vessels. The goals of this study were to develop a robust, automated closed contour edge detection algorithm, apply this algorithm to high resolution human carotid artery images, and assess its accuracy, and reproducibility. Our algorithm has proven to be sensitive to various contrast situations and is reasonably accurate and highly reproducible.

Power spectral analysis of vertebral trabecular bone structure from radiographs: orientation dependence and correlation with bone mineral density and mechanical properties

Trabecular bone structure and bone density contribute to the strength of bone and are potentially important in the study of osteoporosis. Fourier transforms of the textural patterns in radiographs of trabecular bone have previously been used for the measurement of trabecular bone structure in subjects, however, the relationship between these measures and biomechanical properties of bone have not previously been established. In this study radiographs were acquired of 28 cubic specimens of spinal trabecular bone along each of the three anatomic axes: cranio-caudal or superior-inferior (SI), medial-lateral (ML), and anterior-posterior (AP). The radiographs were digitized, background corrected, and uniformly aligned. The Fast Fourier transform (FFT) was performed on a region comprised solely of trabecular bone for each image. The zero (DC), first (FMO), and second moments (SMO) of the Fourier power spectrum and the fractal dimension (FD) as determined from the Fourier power spectrum were correlated with stereology measures, with bone mineral density (BMD) as well as with measured biomechanical properties [Young's elastic modulus (YM) and ultimate strength] of the cubes. The results show that the power spectra-based measures, when compared with structural parameters determined using 3D stereology, show good correlations with bone volume fraction, trabecular spacing, thickness, and number. These power spectral measures showed fair to good correlations with BMD and the biomechanical properties. Moreover, the correlations between the power spectral measures of trabecular structure and the BMD, YM, and stereology measures of structure depend on the orientation of the radiographic image. Specifically, these were significant differences in the measured biomechanical properties and the power spectral measures of the trabecular structure between the SI and ML and the SI and AP directions. In addition, depending on the spatial frequency range for analysis, the fractal dimension showed opposite trends with changes in BMD and biomechanical properties. Multivariate regression models showed the correlation coefficients increasing with the inclusion of some of the power spectral measures, suggesting that FFT-based texture analysis may play a potential role in studies of osteoporosis.

Absence of bradycardic response to apnea and hypoxia in heart transplant recipients with obstructive sleep apnea

In patients with obstructive sleep apnea, the vagal stimulation caused by inspiration against the upper airway obstruction results in sinus bradycardia during the apnea followed by a reflex tachycardia at apnea termination. We report on five heart transplant recipients with obstructive sleep apnea who demonstrated no change in baseline heart rate in spite of marked hemoglobin oxygen desaturation, presumably on account of parasympathetic denervation of the allograft. Heart transplant recipients with obstructive sleep apnea may be at an increased risk of development of potentially fatal ventricular arrhythmias if the allograft is unable to respond appropriately to hypoxia. Should cardiac parasympathetic reinnervation occur, prospective polysomnography may be a marker for this process in these patients.

In vitro antiviral activity of 141W94 (VX-478) in combination with other antiretroviral agents

141W94 (VX-478) is a novel HIV-1 protease inhibitor with an IC50 of 0.08 microM against HIV-1 (strain IIIB) and a mean IC50 of 0.012 microM against six HIV clinical isolates. 141W94 was synergistic on the basis of isobologram analysis with each of the following reverse transcriptase inhibitors: AZT, 935U83, 524W91, 1592U89 and ddl, 141W94 was also synergistic with saquinavir and additive with either indinavir or ritonavir. Resistance to 141W94 has been reported in vitro passage experiments. The binding of 141W94 to human alpha 1-acid glycoprotein was relatively weak (Kd = 4 microM) and the off-rate for the drug is very fast (> or = 100 s-1). Only a 2-fold reduction of in vitro antiviral activity was observed in the presence of 45% human plasma. No serious drug associated adverse experiences were reported in a Phase I placebo-controlled, single-dose escalation, pharmacokinetic and safety study. The average concentration of 141W94 at 8 and 12 h after single doses of 900 and 1200 mg, respectively, was in excess of 10 times the IC50. As 141W94 is synergistic with a variety of anti-HIV-1 agents and exhibits a unique cross resistance profile compared to other protease inhibitors, 141W94 is considered a good candidate for combination therapy.

Suicide and suicide attempts in the lesbian and gay community

The most common suicide theories share a widely recognized set of social factors that contribute to suicide and suicide attempts. This paper discusses additional suicide risk factors that affect the gay and lesbian community such as: discrimination, gay adolescence, coming out, establishment of a gay identity, HIV/AIDS, intrapersonal stressors, drugs and alcohol, racial/ethnic factors and limited support structures. Poor awareness of these additional risks, both within mainstream society and within the gay and lesbian community, is also discussed. A review of the literature is conducted that examines the impact of these risk factors and the implications of these issues to mental health nursing.

Effect of demand frequency on lockout period. The Abbott Provider 5500 Patient-Controlled Analgesia machine

An Abbott Provider 5500 Patient Controlled Analgesia machine was noticed to have developed a prolonged lockout period when frequent analgesic demands were being made. This study tested five other machines and demonstrated that the duration of the lockout period was influenced by the frequency of analgesic demands. This finding could have clinical implications and we recommend that the duration of the lockout period should be specifically examined during the testing of patient-controlled machines.

Zidovudine in persons with asymptomatic HIV infection and CD4+ cell counts greater than 400 per cubic millimeter. The European-Australian Collaborative Group

BACKGROUND

Zidovudine therapy is of benefit in the treatment of symptomatic and asymptomatic human immunodeficiency virus (HIV) infection in persons with CD4+ cell counts of less than 500 per cubic millimeter. The efficacy, safety, and duration of benefit of zidovudine in those with 500 or more CD4+ cells per cubic millimeter are uncertain.

METHODS

In a double-blind, placebo-controlled trial, 993 patients with asymptomatic HIV infection and CD4+ cell counts above 400 per cubic millimeter were randomly assigned to receive zidovudine (500 mg twice daily) or placebo for three years. The primary end point was progression of disease, as defined by the development of Centers for Disease Control and Prevention (CDC) group IV disease (including recurrent oral candidiasis, hairy leukoplakia, or progressive diarrhea) or two CD4+ cell counts below 350 per cubic millimeter. This outcome measure was changed from the original end point of the acquired immunodeficiency syndrome (AIDS) or advanced AIDS-related complex to reflect changes in recommendations for management. The study was terminated after the first interim analysis.

RESULTS

Disease progression was significantly less frequent in the zidovudine group (relative risk, 0.56; 95 percent confidence interval, 0.43 to 0.75; P < 0.001 by the log-rank test). The probability of disease progression at two years was 0.19 with zidovudine, as compared with 0.34 with placebo (95 percent confidence interval for the difference, -0.21 to -0.08). Progression to CDC group IV disease was reduced by half in the zidovudine recipients (relative risk, 0.49; P = 0.049) and decline in CD4+ cell counts to below 350 per cubic millimeter was reduced by 40 percent (relative risk, 0.60; P < 0.001). The inclusion of early HIV disease events (oral candidiasis, oral hairy leukoplakia, and herpes zoster) as end points confirmed the effects of zidovudine on the progression of clinical disease (relative risk, 0.55; 95 percent confidence interval, 0.37 to 0.84; P = 0.004). The median duration of treatment was 94 weeks. Severe hematologic or clinical side effects were rare.

CONCLUSIONS

Treatment with zidovudine benefits HIV-infected persons with CD4+ cell counts above 400 per cubic millimeter. Despite the use of doses larger than those now generally prescribed, zidovudine was well tolerated for up to three years by most of our patients.

Health visiting an elderly couple

Health visitors play an important role in their involvement with the elderly population. As Parkinson's disease becomes increasingly prevalent among elderly people, a multidisciplinary approach to treatment and care is essential in the holistic assessment and management of the condition. The importance of the carer in the life of the elderly person with Parkinson's disease cannot be overemphasized. Effective two-way communication and involvement of both the sufferer and main carer in decisions about treatment and care are essential. Effective communication between all members of the primary healthcare team is necessary for continuity of care and support. The use of the Neuman System Model in this case demonstrates the way in which tools of assessment can influence our perception of the client, the type of information obtained and the care and support clients receive.

H2-antagonist inhibition of human neutrophil superoxide anion synthesis

In the mmol/L concentration range, cimetidine and ranitidine suppress superoxide anion generation by isolated intact human neutrophils. However, at normal pharmacologic concentrations in the mumol/L range, even prolonged exposure of neutrophils to these agents has no demonstrable effect on toxic oxygen species synthesis. In vitro inhibition does not involve neutrophil activation-densensitization or neutrophil cytotoxicity and is reversible to a great extent by drug washout. In the examination of possible free-radical scavenging action of these drugs, it was demonstrated that both drugs inhibit superoxide anion production by xanthine oxidase but not by chelated iron. This raises the possibility that these agents may bear structural similarities to oxypyrazolopyrimidines such as allopurinol.

How hospital ward members treat learner nurses: an investigation of learners' perceptions in a British hospital

Twenty-five learner nurses who had just completed their first two wards were questionned about the behaviour of other ward members towards them. Although many ward sisters' and charge nurses' behaviour was positive towards learners, just under 50% of learners' responses indicated that the ward sister/charge nurse was sometimes rude and did not make them feel 'at home'. The ward sister/charge nurse's behaviour was, on average, more negative than another liked qualified staff, whose behaviour was more negative than a more experienced student on the ward. The ward sister/charge nurse's behaviour was the major determinant of ward preference by the learner. However, the behaviour of ward members tended to correlate, providing evidence of a 'ward atmosphere'. There is a need for leadership and educational training for ward sisters and charge nurses.

Studies on heat inactivation of hepatitis A virus with special reference to shellfish. Part 1. Procedures for infection and recovery of virus from laboratory-maintained cockles

The consumption of bi-valve molluscan shellfish has been associated with outbreaks of viral gastroenteritis and hepatitis A. Investigations were undertaken to determine the heat inactivation conditions necessary to render shellfish such as cockles safe for the consumer. Conditions for the laboratory maintenance of live cockles are described. In preliminary experiments either poliovirus (10(6) TCID50/ml seawater) or hepatitis A virus (HAV) (approx. 10(4) RFU/ml seawater) was introduced into the shellfish tank. Following 48 h filter feeding, virus was recovered from cockles using an adsorption-elution extraction procedure. Titres of virus recovered ranged from 10(4) to 10(5) TCID50/ml of shellfish extract for poliovirus and from 10(3) to 10(5) RFU/ml of shellfish extract for HAV. Active ingestion of the virus from the seawater was demonstrated by recovering virus from within cockle guts. To quantify recovered HAV, end-point dilutions and an adaptation of a radioimmunofocus assay (RIFA) were compared. The tests were of similar sensitivity but the RIFA has the advantage of being relatively rapid, shortening the time taken to complete an experiment by as much as 4 weeks.

The assessment of human exposure to radionuclides from a uranium mill tailings release and mine dewatering effluent

This study provides an assessment of human exposure to radiation from a river system contaminated by radionuclides of the 238U decay series released through a dam break at a uranium mill tailings pond and by the continuous discharge of dewatering effluent from 2 uranium mines. The in vivo analyses of radionuclides in 6 Navajo Indians who lived near the river indicate no detectable elevations above background concentrations. Dose estimates for inhalation of suspended river sediment indicate a maximum annual 50-yr dose commitment of 204 mrem to the endosteum. Estimates of doses (50-yr dose commitments) from the ingestion of livestock range between 1 mrem (to liver) and 79 mrem (to bone) suggest that the major contribution to human exposure is from mine dewatering effluent that has been continuously released into the river system for many years. Although the estimated exposures do not exceed existing state or federal regulations, their magnitude justifies further measurement of radionuclides in animals and in the natural environment and the consideration of strategies to reduce radiation exposure to humans and animals.

Some Points in the Growth of the Face

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