Increasing the response rates of reluctant professionals to mail surveys.
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Bias↗
Biomedical subjects
C A Murphy
Publications and source records attributed to C A Murphy.
An adult case of acute biphenotypic leukemia with characteristic mixed morphology.
A case of acute biphenotypic leukemia with mixed blast morphology and combined myeloid and T-lymphoid features is reported. The leukemic cells consisted of small lymphoid hand-mirror blasts and large blasts with cytoplasmic granules and rare Auer rods. The cells expressed myeloid and immature T-lymphoid features by cytochemistry and immunophenotyping, however T cell receptor genes were in germline configuration. Cases of biphenotypic leukemia with similar morphological and immunophenotypic findings have been described previously in children. This case represents a morphologically and phenotypically distinct subtype of acute biphenotypic leukemia.
Adult↗
Development and validation of the Perinatal Nursing Self-Efficacy Scale.
Self-efficacy, a central construct of Bandura's social cognitive theory, provided the framework for developing a measure of perinatal nursing knowledge and skills. The 24-item Perinatal Nursing Self-efficacy Scale (PNSE) encompasses knowledge and skills required of nurses practicing in family-centered single room maternity care (SRMC) settings. Response data from 188 registered nurses were evaluated to assess the reliability and construct validity of the instrument. The instrument demonstrated strong factorial validity and subscales derived from the factor analysis generated high alpha reliabilities. A MANOVA produced results consistent with the propositions of self-efficacy theory and supported construct validity. Since self-efficacy expectations are situation specific and have significant predictive value, they provide both an important adjunct to needs assessment data for educational planning and helpful baseline data for outcome evaluation of perinatal nursing educational programs and transitions to SRMC settings.
Adult↗
Maternal involvement in the development of cardiovascular phenotype.
Over the past 20 years, laboratory studies of genetically defined animal models of human essential hypertension have provided valuable information on the pathophysiology of this disturbance in cardiovascular regulation. Relatively fewer studies have examined the impact of preweaning factors on the developing cardiovascular system of hypertensive animals. In our laboratory studies, we have utilized two inbred genetically hypertensive models: the spontaneously hypertensive (SHR) rat and its Wistar/Kyoto (WKY) normotensive control strain as well as the Dahl hypertension-sensitive (SS/Jr) and hypertension-resistant (SR/Jr) strains. To manipulate the preweaning maternal environment, we have employed the technique of reciprocal cross-fostering of litters between hypertensive and matched normotensive mothers. Our findings to date point to the maternal environment as a powerful influence on the development of high blood pressure in genetically hypertensive rats. In general, hypertensive rats reared by normotensive foster mothers have significant reductions in arterial blood pressure in adulthood. Thus, the progression of hypertensive disease is not strictly predetermined by genotypic factors. Rather, a genetic predisposition to hypertension interacts with preweaning environmental factors to determine an animal's cardiovascular phenotype in adulthood.
Animals↗
Shared maternal influences in the development of high blood pressure in the spontaneously hypertensive (SHR) and Dahl salt-sensitive (SS/Jr) rat strains.
The influence of maternal environment on the development of high blood pressure in spontaneously hypertensive (SHR) and Dahl salt-sensitive (SS/Jr) rats was examined using the technique of reciprocal cross-fostering. Previous experiments from this laboratory demonstrated that adult blood pressures of the SHR and SS/Jr strains were significantly attenuated when hypertensive-strain pups were fostered to a dam of the respective normotensive control strain during the preweaning period. In this study, SHR and SS/Jr pups were assigned to either a cross-fostered (fostered to a dam of the opposite hypertensive strain) or control-reared condition within 24 h of birth. Adult resting blood pressures were similar in control and cross-fostered SHR rats and in control and cross-fostered SS/Jr rats. Heart rates and heart, adrenal, and kidney weights were also similar in control and cross-fostered rats of each strain. However, body weights of SHR rats reared by an SS/Jr dam were somewhat lower compared to control-reared SHR rats. These data indicate that the maternal environments provided by SHR and SS/Jr mothers are similar in some way such that they permit the development and full expression of the hypertensive phenotype in both same-strain and opposite-strain pups.
Animals↗
Selective aortic arch perfusion during cardiac arrest: a new resuscitation technique.
STUDY OBJECTIVES: To demonstrate the technique of selective aortic arch perfusion during cardiac arrest and to observe the hemodynamic effects of volume infusion and aortic epinephrine administration. DESIGN: Sequential series, nonrandomized, noncontrolled. TYPE OF PARTICIPANTS: Fourteen mongrel dogs weighing 21 to 36 kg. INTERVENTIONS: Animals had midaortic arch pressure, right atrial pressure, and descending aortic arch balloon occlusion catheters placed. After ten minutes of ventricular fibrillation, balloon inflation and aortic arch infusions were initiated as follows: group 1 (six), 30 mL/kg/min of 0.9% NaCl for two minutes; group 2 (four), 30 mL/kg/min of oxygenated lactated Ringer's with 2 mg/L epinephrine for two minutes, followed by CPR; and group 3 (four), 20 mL/kg/min of oxygenated perfluorochemicals with 4 mg/L epinephrine for one minute, then CPR. MEASUREMENTS AND MAIN RESULTS: Midaortic arch pressure, right atrial pressure, and coronary perfusion pressure each rose significantly in all groups. Midaortic arch pressure and coronary perfusion pressure increases were greater in groups 2 and 3 than in group 1. In groups 1 and 2, right atrial pressure increases at end-selective aortic arch perfusion were excessive as midaortic arch pressure and right atrial pressure increased linearly and similarly after 20 to 30 seconds. In groups 2 and 3, CPR-diastolic midaortic arch pressure and coronary perfusion pressure after selective aortic arch perfusion were good and similar to midaortic arch pressure and coronary perfusion pressure at end-selective aortic arch perfusion. CONCLUSION: Selective aortic arch perfusion is technically feasible, but excessive right atrial pressure increases limit maximal infusion rates and volumes. Selective aortic arch perfusion infusates with epinephrine produce greater midaortic arch pressure and coronary perfusion pressure during infusion than infusate without epinephrine. Controlled studies are needed to determine if selective aortic arch perfusion improves resuscitation outcome.
Animals↗
Searching for proper judicial recognition of hospital ethics committees in decisions to forego medical treatment.
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Decision Making, Organizational↗
Cryptomonad algae are evolutionary chimaeras of two phylogenetically distinct unicellular eukaryotes.
Although it is widely accepted that the plastids of plants and algae originated as endosymbionts, the details of this evolutionary process are unclear. It has been proposed that in organisms whose plastids are surrounded by more than two membranes, the endosymbiont was a eukaryotic alga rather than a photosynthetic prokaryote. The DNA-containing nucleomorph of cryptomonad algae appears to be the vestigial nucleus of such an algal endosymbiont. Eukaryotic-type ribosomal RNA sequences have been localized to a nucleolus-like structure in the nucleomorph. In support of the hypothesis that cryptomonads are evolutionary chimaeras of two distinct eukaryotic cells, we show here that Cryptomonas phi contains two phylogenetically separate, nuclear-type small-subunit rRNA genes, both of which are transcriptionally active. We incorporate our rRNA sequence data into phylogenetic trees, from which we infer the evolutionary ancestry of the host and symbiont components of Cryptomonas phi. Such trees do not support the thesis that chromophyte algae evolved directly from a cryptomonad-like ancestor.
Animals↗
Pharmacologic responses and spectral analyses of spontaneous fluctuations in heart rate and blood pressure in SHR rats.
The aim of this experiment was to characterize patterns of autonomic control in spontaneously hypertensive (SHR) and normotensive Wistar-Kyoto (WKY) rats by measuring effects of pharmacologic blockers and using power spectral analysis of heart rate variability (HRV) and blood pressure variability (BPV). Resting HRs and BPs were recorded during a 20-min baseline period and over two 20-min periods of sequential autonomic blockade. On one day, animals received atropine followed by atenolol and on the following day, the drug order was reversed. Power spectrum analyses were performed on 30-s blocks of data throughout each of the three 20-min treatment periods (baseline, single blocker, combined blockade) and HRV and BPV were computed over low and high frequency bands. Increases in HR after atropine were significantly (approx. 40%) smaller in SHR rats than in WKYs. This held true even when animals were pretreated with atenolol. In contrast, decreases in HR following atenolol were similar in the two strains. These results indicate that SHRs have reduced vagal tone, but similar cardiac sympathetic tone compared to WKY rats. Virtually all HRV, over both low and high frequency bands, and in both strains, was inhibited by atropine. SHRs had significantly less high frequency HRV which is consistent with the conclusion that they have reduced cardiac vagal activity when compared with WKYs. BPV was not affected by atropine or atenolol but was inhibited by an alpha-receptor (phentolamine). BPV within both the low and high frequency bands was significantly greater in SHRs, suggesting that sympathetic tone to the vasculature is greater in SHR rats.
Animals↗
Cardiac output by impedance cardiography: two alternative methodologies compared with thermodilution.
One critical component of the Kubicek (8) stroke volume equation, used to measure cardiac output by impedance cardiography, is dZ/dt(max). The present study, conducted on six anesthetized dogs, compared impedance cardiac output derived using two alternative methods of quantifying dZ/dt(max), with simultaneous thermodilution measures. Values for dZ/dt(max) quantified relative to dZ/dt = 0 baseline and relative to the dZ/dt B-point were entered into the Kubicek equation to generate cardiac output measures designated as impedance-A and impedance-B, respectively. Emphasis was placed upon evaluating impedance cardiac output within its accepted limits as a relative change measure. Systematic alterations in cardiac output were produced by intravenously administered isoproterenol, phenylephrine and nitroprusside. Drug-induced changes in cardiac output measured by the impedance-A method were statistically identical to thermodilution. For the impedance-B method, similarity to thermodilution was limited to two of the three drug conditions. Correlations of impedance cardiac output with thermodilution tended to be higher for the impedance-A method. Together with theoretical and practical considerations, these results support quantification of dZ/dt(max) relative to dZ/dt = 0 when used in the Kubicek stroke volume equation.
Animals↗
Nucleotide sequences of 18S ribosomal RNA genes from the red algae Gracilaria tikvahiae McLachlan, Gracilaria verrucosa (Hudson) Papenfuss and Gracilariopsis sp.
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Base Sequence↗
Maternal behavior of spontaneously hypertensive and Wistar-Kyoto normotensive rats: effects of reciprocal cross-fostering of litters.
Maternal behavior of spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) normotensive dams rearing either their natural pups or pups of the opposite strain was assessed when pups were 4-6 days of age. Consistent with previous reports, SHR dams caring for their natural pups were observed nursing and licking their pups more often than WKY dams and were away from their pups less often. The behavior of dams rearing cross-fostered pups demonstrated that this strain difference in patterns of maternal behavior is dependent on pup type. Mothers of both strains shifted their behavior in the direction of the opposite strain's maternal behavior pattern when caring for cross-fostered pups. This shift was most pronounced in SHR dams caring for WKY pups. These data suggest that alterations in patterns of maternal behavior produced by cross-fostering may play an important role in cross-fostering effects on the physiological development of SHRs previously reported.
Animals↗
Sympathetic-adrenal medullary responses to acute stress in Dahl hypertensive (S/JR) rats.
Sympathetic-adrenal medullary responses to acute footshock stress were assessed in inbred Dahl salt-sensitive (S/JR) and salt-resistant (R/JR) rats by measuring plasma levels of norepinephrine (NE) and epinephrine (EPI). Ten-week-old S/JR and R/JR rats were surgically prepared with indwelling tail artery catheters which permitted direct measurements of mean arterial pressure (MAP, mmHg) and heart rate (HR, beats/min) and remote sampling of blood. Two days after surgery, S/JR and R/JR rats were subjected to an acute stress paradigm. Blood samples were collected before and 3 minutes after transfer of rats to a shock chamber, after 1 minute of intermittent footshock, and again 5 minutes later. S/JR rats had significantly higher resting MAP's compared to R/JR rats. In contrast, baseline heart rates were similar for rats of the two strains. Basal plasma levels of NE and EPI were also similar in S/JR and R/JR rats. Upon transfer from the home cage to a shock chamber, S/JR rats exhibited significant increases in plasma levels of both catecholamines, while R/JR rats maintained circulating levels of NE and EPI that were near baseline values. However, S/JR and R/JR rats had similar increments in plasma NE and EPI following acute footshock stress. Five minutes after footshock, levels of NE and EPI returned toward baseline values for R/JR's, but remained significantly elevated above baseline in hypertensive S/JR rats. These data suggest that S/JR rats are more responsive than R/JR controls to the mild stress of transfer, but exhibit comparable responses to the more intense stress of inescapable footshock.(ABSTRACT TRUNCATED AT 250 WORDS)
Adrenal Medulla↗
Open-field behavior of spontaneously hypertensive and Wistar-Kyoto normotensive rats: effects of reciprocal cross-fostering.
The influence of the maternal environment on the development of open-field behavior in spontaneously hypertensive (SHR) rats was investigated using the technique of reciprocal cross-fostering. Entire litters of SHR and Wistar-Kyoto (WKY) normotensive rats were either reared by their natural mothers, in-fostered to dams of the same strain, or cross-fostered to dams of the opposite strain on the day after birth. Open-field behavior was assessed in male and female rats from the six groups (2 strains x 3 rearing conditions) at 30, 60, 90, and 120 days of age. Animals were observed in the open-field during a 5-min test period and the number of squares entered and hindlimb rears were recorded. At all ages tested, SHR rats were more active in the open field, entering more squares and rearing more frequently than WKYs. SHR females were more active than age-matched SHR males, while no sex differences were apparent in the WKY strain. At each age, open-field behavior was similar across WKY rearing groups. SHR control and in-fostered animals responded similarly in the open field; however, SHR cross-fostered rats (particularly females) tended to be more active than controls. Although cross-fostering has profound effects on cardiovascular development and functioning in the SHR, it appears that altering the early maternal environment experienced by SHR pups does not grossly affect the development of open-field behavior.
Animals↗
The PRN plan: professional reimbursement for nurses.
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Humans↗
Maternal environment and development of high blood pressure in Dahl hypertensive rats.
The contribution of the preweanling maternal environment to the development of hypertension was examined using the technique of reciprocal cross-fostering between two inbred rat strains, the Dahl hypertension-sensitive (SS/Jr) rat and the Dahl hypertension-resistant (SR/Jr) rat. Litters of SS/Jr and SR/Jr pups were reared by their natural mother, in-fostered to a dam of the same strain, or cross-fostered to a dam of the opposite strain for the entire preweanling period from postnatal days 1 to 30. At 60 and 100 days of age, one rat from each litter was surgically prepared with an indwelling catheter in the ventral tail artery. One day after surgery, measures of resting mean arterial pressure and heart rate were taken as the animals were resting and undisturbed in their home cages. Body weights were also obtained at 30, 60, and 100 days of age as a measure of general somatic development. Our findings indicate that SS/Jr rats fostered to SR/Jr dams exhibited a significant reduction in resting mean arterial pressure compared with naturally reared or in-fostered SS/Jr rats (P less than 0.01 at 60 days and P less than 0.03 at 100 days). Conversely, arterial pressure of SR/Jr rats did not differ across rearing conditions at either age. Body weights were not significantly affected by cross-fostering in either strain. We conclude from these results that characteristics of the SS/Jr maternal environment interact with the inbred genetic susceptibility of the SS/Jr pup to elicit the full expression of the SS/Jr hypertensive phenotype.
Animals↗
Sympathetic responses of the heart and adrenal medulla in developing Dahl hypertensive rats.
Functional development of the sympathetic nervous system was examined in inbred Dahl salt-sensitive (S/JR) and salt-resistant (R/JR) rats by assessing cardiac and adrenal medullary responses to insulin-induced hypoglycemia at 2, 4, 8, 12, and 16 days of age. Heart ornithine decarboxylase (ODC) activity and adrenal catecholamine content were measured in pups of the two strains 3 hours after administration of either saline or insulin. The centrally mediated increase in sympathetic outflow caused by insulin-induced hypoglycemia was attended by induction of heart ODC activity and depletion of adrenal epinephrine (EPI). No significant differences were found overall between R/JR and S/JR strains with regard to either heart ODC activity or adrenal epinephrine. This was true for basal values obtained from saline-injected pups as well as for measures from insulin-injected pups. Functional innervation of the heart was present in pups of both strains as early as 2 days of age, while in the adrenal medulla a significant response to stimulation was not detected until 8 days of age. While the susceptibility for hypertension in the salt-sensitive animals may well be linked to increased sympathetic tone, the present findings indicate that S/JR rats do not have an accelerated development or a hyperresponsiveness of sympathetic input to either the heart or the adrenal medulla during the pre-weanling period.
Adrenal Glands↗
An antegrade surgical uterine flush technique for ova collection in the ewe.
A surgical uterine flush technique was evaluated for percentage of ova/corpora lutea (CL) collected and development of reproductive adhesions in 79 superovulated ewes. The median collection rate for ova/CL was 70%, and 47 of 79 ewes had greater than or equal to 67% ova/CL. At 50 to 80 days after uterine flushing, celiotomies were performed on 50 of the 79 ewes to evaluate the reproductive tract for adhesions. Adhesions of the reproductive tract were not found. Thirty ewes were given prostaglandin F2 alpha, were mated, and became pregnant. The ova collection rates were comparable with rates reported in ewes in which oviductal flush methods were used; however, adhesions did not develop and reproductive function was maintained after surgery.
Animals↗