An analysis of attitude toward infant sleep safety and SIDS risk reduction behavior among caregivers of newborns and infants.

OBJECTIVE: To explore beliefs and attitude toward infant sleep safety and sudden infant death syndrome (SIDS) risk reduction behaviors among caregivers of newborns and infants. STUDY DESIGN: A convenience sample comprised of 121 caregivers of newborns at Staten Island University Hospital completed a questionnaire. RESULTS: Despite an overall favorable attitude toward safe sleep practices, a majority disagreed with use of pacifiers (53%) and believed that swaddling (62%) as well as the use of home monitors (59%) are acceptable practices. The caregivers who recalled being taught about safe sleep had higher perception of infant vulnerability (P<0.001), more confidence in their ability to implement safe sleep behaviors (P<0.0006) and stronger belief that safe sleep behaviors are effective (P<0.01). CONCLUSION: Active caregiver education may result in more effective demonstration of safe sleep and SIDS risk reduction behaviors. Further study is needed to assess if favorable attitudes toward safe sleep practices correlate with actual demonstrated behaviors.

Factors influencing midwifery migration from the United Kingdom to Australia.

BACKGROUND: Within the current literature on the globalization of the healthcare workforce, it is difficult to separate the migration experience of nurses from that of midwives. As more countries are moving to offer direct entry educational programmes and provide separate registration for midwives, information specific to that professional group will be required to guide workforce planners and inform employment practice. This qualitative study tracks the migration experience of midwives moving between the UK and Australia. METHODS: A purposeful sample of 18 midwives who had migrated from the UK to one state in Australia was interviewed within a descriptive phenomenological framework. Data were analysed using thematic coding within Nvivo (QSR International, Melbourne, Australia). RESULTS: The strongest motivator for migration was to improve the family's lifestyle. Push factors included disillusionment with working conditions, standard of living in the UK and national politics. The majority of midwives had organized their own entry visa and employment. Most midwives had occupied senior positions in the UK but accepted employment initially within entry-level positions in Australia. DISCUSSION: Despite both countries offering similar standards of living, the majority of midwives expected to achieve an improvement in family lifestyle in Australia. Midwives indicated they were prepared to lose professional status and seniority of position to gain a better overall lifestyle for their family. To examine the long-term sustainability of international recruitment processes, further research is indicated to examine the ongoing experience and integration of migrant midwives into the workforce in Australia.

Stress and coping in Australian nurses: a systematic review.

AIM: To identify factors that contribute to stress in Australian nurses, consider the coping strategies they use and examine the effects of stressors on nurses' health and well-being. BACKGROUND: Stress is a major concern in the nursing profession with work overload, nurse shortages and high turnover rates as the common stressors. Although nursing stress has been studied extensively, there is a lack of clarity on the nursing situation in Australia. METHODS: A systematic review of the current literature was conducted on stress and coping strategies within the Australian nursing population. RESULTS: Stressors included work overload, role conflicts and experiences of aggression. Coping strategies included seeking support, problem solving and self-control. The majority of the studies reported detrimental effects on nurses' physical and mental well-being with little consideration given to the spillover effects of nursing work stress to their family and social relationships. CONCLUSION: Recommendations included factoring in personal and work stresses, promoting the use of effective coping strategies and maintaining supportive social relationships.

The professional consequences of whistleblowing by nurses.

When nurses encounter misconduct in the workplace, their ethical codes of conduct bind them to the role of patient advocacy and compel them to safeguard the patient from harm. However, reporting misconduct can be personally and professionally risky. The aim of the research was to examine the professional consequences of whistleblowing and nonwhistleblowing in nursing. A descriptive survey design was used to examine the professional effect of reporting misconduct (whistleblowing) and not reporting misconduct (nonwhistleblowing). Ninety-five respondents were included in the study; 70 were self-identified as whistleblowers and 25 were self-identified as nonwhistleblowers. Results indicated that there were severe professional reprisals if the nurse reported misconduct, but there were few professional consequences if the nurse remained silent. Official reprisals included demotion (4%), reprimand (11%), and referral to a psychiatrist (9%). Whistleblowers also reported that they received professional reprisals in the form of threats (16%), rejection by peers (14%), pressure to resign (7%), and being treated as a traitor (14%). Ten per cent reported that they felt their career had been halted. These findings suggest that when nurses identify and report misconduct in the workplace, they may experience serious professional consequences.

The nurse lecturer role in clinical practice conceptualized: helping clinical teachers provide optimal student learning.

Despite the fairly wide reporting in the literature of the many roles of clinical supervision by the nursing teacher, little attention has been given to conceptualizing the relative priorities these roles take during the process of supervising nursing students in clinical practice. The purpose of this paper is to consider the manifestations and implications of conflicting roles when nurse lecturers undertake clinical supervision. Previously published research will provide working examples of issues in a conceptual framework for clinical teaching.

Prospective randomized study of stapled versus unstapled mesh in a laparoscopic preperitoneal inguinal hernia repair.

BACKGROUND: In 1975, researchers introduced the use of a large unsutured polyester mesh prosthesis placed in the preperitoneal space for inguinal hernia repair. Different stapling devices have been used to secure this mesh, and the most common complication of the procedure is nerve damage secondary to the staples. The necessity of stapling has never been demonstrated. We designed a prospective randomized study of the need for stapling in laparoscopic extraperitoneal repair of inguinal hernias with 1-year and 3-year followup. STUDY DESIGN: Inclusion criteria of the study were men older than 18 years and first-time inguinal hernia repair. Patients with recurrence and previous abdominal operations were excluded to avoid confounding variables. Each patient's hernia was assigned a consecutive random number chosen by computer, with each number corresponding to an assigned group. The first group had stapled mesh and the second had unstapled mesh. RESULTS: Data were collected over a 15-month period, with each procedure having a mean followup time of 8 months. A total of 100 procedures was performed in 92 patients. The two groups of patients were well matched for age and the type of hernia repaired. There were no recurrences in either group and no complications or deaths. CONCLUSIONS: The initial 12-month followup showed no significant differences in recurrence or complication rates between the stapled and unstapled groups. Both groups returned to work within an average of 4 days. A net savings of $120 was realized for each hernia repair performed without stapled mesh. In addition, stapling presents an inherent risk of nerve damage.

Whistle-blowing: effective and ineffective coping responses.

How do nurses respond when they identify misconduct in patient care settings? The authors used a descriptive survey (N = 95) to identify effective coping strategies of whistle-blowers (n = 70) and non-whistle-blowers (n = 25). Results identified four effective coping strategies used by whistle-blowers. The authors offer recommendations to nurses who encounter misconduct in their workplace.

Optimal depth and duration of mild hypothermia in a focal model of transient cerebral ischemia: effects on neurologic outcome, infarct size, apoptosis, and inflammation.

BACKGROUND AND PURPOSE: Mild hypothermia is possibly the single most effective method of cerebroprotection developed to date. However, many questions regarding mild hypothermia remain to be addressed before its potential implementation in the treatment of human stroke. Here we report the results of 2 studies designed to determine the optimal depth and duration of mild hypothermia in focal stroke and its effects on infarct size, neurological outcome, programmed cell death, and inflammation. METHODS: Rats underwent a 2-hour occlusion of the left middle cerebral artery. In the first study (I) animals were kept (intraischemically) at either 37 degreesC (n=8), 33 degreesC (n=8), or 30 degreesC (n=8). Study II consisted of 4 groups: (1) controls (37 degreesC, n=10), (2) 30 minutes of hypothermia started at ischemic onset (33 degreesC, n=9), (3)1 hour (33 degreesC, n=8), and (4) 2 hours (33 degreesC, n=8). Brain temperature was measured by a thermocouple probe placed in the contralateral cortex. After suture removal, all animals were rewarmed and reperfused for 22 hours (I) or 70 hours (II). RESULTS: Mild hypothermia to 33 degreesC or 30 degreesC was neuroprotective (17+/-7% and 27+/-6%, respectively) relative to controls (53+/-8%, P<0.02), but 33 degreesC was better tolerated and recovery from anesthesia was faster. The neurological score of hypothermic animals was significantly better than that of controls (I & II) at both 24 and 72 hours postischemia except for the 30-minute group (II), which showed no improvement. In Study II, 2 hours of hypothermia reduced injury by 59%, 1 hour reduced injury by 84% whereas 30 minutes did not reduce injury. Normalized for infarct size, 2 hours of mild hypothermia decreased neutrophil accumulation by 57% whereas both 1 hour and 30 minutes had no effect. At 72 hours, 1 and 2 hours of mild hypothermia decreased transferase dUTP nick-end labeling (TUNEL) staining by 78% and 99%, respectively, and 30 minutes of hypothermia had no effect. CONCLUSIONS: Intraischemic mild hypothermia must be maintained for 1 to 2 hours to obtain optimal neuroprotection against ischemic cell death due to necrosis and apoptosis.

Total iron-binding capacity-estimated transferrin correlates with the nutritional subjective global assessment in hemodialysis patients.

We examined the value of transferrin concentrations in estimating nutritional status as determined by the subjective global assessment (SGA) score. Fifty-nine hemodialysis patients (37 men and 22 women, aged 59+/-16 years, dialyzed for 3.6+/-3.9 years) were selected by predetermined criteria. All received erythropoietin (EPO) and oral iron therapy. SGA evaluation was conducted twice by both a dietitian and a physician. Serum iron, total iron-binding capacity (TIBC; which is linearly correlated with transferrin), transferrin saturation ratio, ferritin, albumin, total protein, and cholesterol were measured. Twenty-seven (46%) patients were well nourished (group A), 20 (34%) were moderately nourished (group B), and 12 (20%) were poorly nourished (group C) according to the SGA. TIBC values were 276+/-47 mg/dL, 217+/-54 mg/dL, and 176+/-41 mg/dL, respectively (P < 0.00001), and thus directly correlated with the state of nutrition. The relationship between TIBC and nutritional status was independent of age and number of years on hemodialysis. Serum ferritin values were 104+/-93 ng/mL, 161+/-154 ng/mL, and 363+/-305 ng/mL, respectively (P < 0.0003), and thus inversely correlated with the state of nutrition. Transferrin saturation ratios were slightly higher in the severely malnourished patients. The number of years on dialysis were a determinant of nutritional status. These values were 2.4+/-2.4 years for group A, 3.9+/-4.0 years for group B, and 5.7+/-3.9 years for group C (P < 0.05). The average age of the poorly nourished patients was 10 years older than the well-nourished patients. Serum iron values were lower but transferrin saturation ratios were higher in the severely malnourished patients. The required EPO doses were higher in the poorly nourished patients. We suggest that transferrin values are superior to other laboratory tests in assessing nutrition and will supplement SGA criteria. Serum ferritin may be useful as a predictor of illness. Older patients who have been on dialysis longer warrant special concern. Malnutrition may be an indicator of EPO resistance in dialysis patients. Finally, since a decreased TIBC level in poorly nourished patients may erroneously increase the transferrin saturation ratio, our findings may have implications in making the diagnosis and treatment of anemia and iron deficiency in malnourished dialysis patients.

omega-agatoxin IVA and excitotoxicity in cortical neuronal cultures.

Because the P- and Q-type Ca2+ channel antagonist omega-agatoxin IVA inhibits glutamate release, agatoxin-related drugs could have a role in the treatment of excitotoxic neurologic disorders such as stroke. We examined the effect of omega-agatoxin IVA on excitotoxicity (lactate dehydrogenase release) induced by depolarization with veratridine or ouabain, or by N-methyl-D-aspartate, in neuron-enriched cerebral cortical cultures. omega-Agatoxin IVA (< or = 300 nM) failed to reduce excitotoxicity, as did the L-type Ca2+ channel antagonist nimodipine and the N-type antagonist omega-conotoxin GVIA. Drugs that inhibit glutamate release may not necessarily be neuroprotective.

Pre- and post-synaptic modulators of excitatory neurotransmission: comparative effects on hypoxia/hypoglycemia in cortical cultures.

Neuron-enriched cultures from embryonic rat cerebral cortex were exposed to hypoxia and hypoglycemia, and the resulting cellular injury was quantified by measuring lactate dehydrogenase (LDH) release, which was maximal after 20-24 h. The increase in LDH release produced by hypoxia/hypoglycemia was prevented by N-methyl-D-aspartate (NMDA) antagonists, but not by three classes of drugs thought to modulate glutamate release: Ca2+ channel antagonists (nimodipine, omega-conotoxin GVIA, omega-agatoxin-IVA), KATP channel activators (cromakalim, diazoxide), and glutamate transport inhibitors (dihydrokainate, DL-threo-beta-hydroxyaspartate).

Enhancement of NMDA toxicity and calcium responses by chronic exposure of cultured cortical neurons to ethanol.

Exposure of rat cerebrocortical cultures to 100 mM ethanol for 3-4 days increased both the neurotoxic potency of N-methyl-D-aspartate (NMDA) and the maximal extent of NMDA-induced intracellular calcium (Ca2+i) elevations. In both control and ethanol-treated cultures, NMDA toxicity correlated closely with [Ca2+]i. Enhancement of NMDA responses may reflect neuronal adaptation to chronic ethanol exposure and could contribute to the pathogenesis of alcohol-related neurologic disorders.

Calcium indicators and excitotoxicity in cultured cortical neurons.

Membrane-permeating, fluorescent Ca2+ indicators have been used to investigate the role of increased intracellular Ca2+ (Ca2+i) levels in excitotoxic neuronal injury, but their ability to chelate Ca2+i and their own toxic effects in some cells could obscure this relationship. N-Methyl-D-aspartate (NMDA)-stimulated Ca2+i responses and toxicity were measured in neuron-enriched rat cerebrocortical cultures loaded with either fluo-3 or fura-2. Ca2+i responses signaled by both indicators were similar in magnitude, and neither indicator reduced NMDA toxicity, measured by lactate dehydrogenase (LDH) release. Fluo-3 and fura-2 appear to be suitable for comparative studies of NMDA-induced Ca2+i responses and excitotoxicity.

Antiparkinsonian drugs and in vitro excitotoxicity.

N-Methyl-D-aspartate (NMDA) receptor activation has been implicated in the pathogenesis and clinical expression of Parkinson's disease. Because some antiparkinsonian drugs have NMDA antagonist properties, we examined their effects on NMDA toxicity, measured by lactate dehydrogenase (LDH) release, in neuron-enriched cerebrocortical cultures. Amantadine reduced NMDA toxicity with half-maximal reduction at approximately 30 microM, while trihexphenidyl, L-3,4-dihydroxyphenylalanine (L-DOPA), bromocriptine and selegiline were ineffective, and benztropine was itself toxic. Amantadine and related drugs could not only reduce parkinsonian symptoms, but also modify underlying neurodegenerative processes.

Inverted repeats direct repair of adenovirus minichromosome ends.

Adenovirus DNA initiates strand-displacement replication from origins located in identical inverted terminal repetitions (ITRs). Panhandle structures, formed by base pairing between ITRs on the displaced strands, have been proposed as replication intermediates for complementary strand synthesis. We have used a model system, which separates adenovirus replication origin sequences from those involved in panhandle formation, to study the length and sequence integrity of panhandles. By making a series of unidirectional deletion in the panhandle sequence, we show that 31 bp are necessary for panhandle formation. Removal of long stretches of 3'-unpaired nucleotides distal to the panhandle is extremely efficient. Our results argue for the formation of panhandles during adenovirus DNA replication and provide a mechanism for maintaining sequence identity between distantly located inverted repetitions. The size constraint may explain why the adenovirus ITRs are larger than the viral DNA replication origins.

Strands hybridize in postreplicative adenovirus overlap recombination.

We describe a postreplicative mechanism for adenovirus overlap recombination. An adenovirus minichromosome system was used to study overlap recombination driven by adenovirus DNA replication. Crossing-over appeared to occur equally at, but not within, the borders of the overlap between partner molecules. We propose that recombination in the minichromosome system proceeds through an intermediate formed by direct hybridization of complementary sequences on displaced strands generated by adenovirus-specific DNA replication. Some, but not all, heterologous regions in the intermediate are susceptible to mismatch correction. This pathway is intrinsically nonreciprocal and differs significantly from other adenovirus recombinational mechanisms that have been described previously.

Crosslinking of DNA by dehydroretronecine, a metabolite of pyrrolizidine alkaloids.

Dehydroretronecine (DHR), a major metabolite of the pyrrolizidine alkaloids, has been shown to bind and crosslink pBR322 plasmid DNA and M13 viral DNA, as monitored by electron microscopy and agarose gel electrophoresis. The crosslinking was alkali-stable and varied with time, temperature, pH and reactant ratios. Although the binding of DHR to single-stranded M13 DNA was 3-fold higher than to double-stranded M13 DNA, only the double-stranded DNA was crosslinked. Intra- and inter-molecular crosslinking occurred with both linear and circular forms of double-stranded DNA. Electron microscopy showed that incubations with low DHR/DNA ratios yielded mostly DNA monomers and dimers while higher ratios produced larger aggregations, some of which were equivalent in size to dozens of individual DNA molecules. The average number of intermolecular crosslinks per molecule estimated by Poisson statistics was essentially the same using data from electron microscopy or DHR-binding. DHR generated single strand scissions equally well in both single- and double-stranded molecules.