The use of antibodies to investigate the role of factor XI in platelets.
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Animals↗
Biomedical subjects
I Smith
Publications and source records attributed to I Smith.
Early spo gene expression in Bacillus subtilis: the role of interrelated signal transduction systems.
The early spo genes are subject to a number of different control mechanisms. We found that at least one histidine kinase, SpoIIJ, is important for the expression of early spo genes but that two others, ComP and DegS, also affect sporulation, especially when SpoIIJ is absent. This indicates the existence of a signal transduction network which may gather information from several sources to feed into the sporulation pathway. Early spo gene expression is inhibited by overproduction of two response regulators, SpoOF and ComA. This effect is eliminated by the elevated presence of their cognate histidine kinases, SpoIIJ and ComP, respectively. This suggests that the unphosphorylated response regulators cause the inhibition of sporulation.
Bacillus subtilis↗
Effects of cocaine and alcohol use in pregnancy on neonatal growth and neurobehavioral status.
Effects on fetal growth and neonatal behavior of cocaine and alcohol use in pregnancy were investigated in infants born to women in a low-income, predominantly black population. Despite the increased use of cocaine by pregnant women and the accompanying public concern, behavioral studies of exposed neonates are limited in number and scope. In most studies, confounding factors (e.g., polydrug abuse, prematurity, infant health status) have not been controlled so the actual effects of cocaine and other drug exposure are not clear. Accordingly, this study investigated effects of prenatal drug exposure although controlling experimentally for other factors known to be associated with poor outcomes in infants: prematurity, other illicit drug use, associated diseases (e.g., sexually transmitted diseases [STDs]), and duration of drug use. In addition, other factors statistically controlled were: experimenter effects, timing of assessment, and effects of duration, amount, and frequency of cocaine, alcohol, marijuana, and nicotine exposure. One hundred and seven full-term infants were assessed at 2, 14, and 28 days using the Brazelton Neonatal Behavioral Assessment Scale (BNBAS) by testers blind to infant status. Growth factors (i.e., birthweight, length, head circumference) were also assessed.
Adult↗
The role of negative control in sporulation.
Negative controls play an important role in the regulation of differentiation in many organisms. Sporulation in Bacillus subtilis is also regulated by DNA-binding proteins which exert a repressive effect on genes which are essential for this process. AbrB represses spo0H, coding for sigma H. One of the earliest events in the initiation of sporulation is the lifting of this repression so that more sigma H can be made. As part of an RNA polymerase holoenzyme, this positive transcription factor is responsible for the elevated synthesis of sufficient phosphorylated Spo0A to activate the expression of several stage II genes. Sin, another DNA-binding protein, represses the same genes, spoIIA, spoIIE and spoIIG, that are activated by Spo0A. Thus sporulation is controlled at the two earliest stages by at least two repressors. Sin and AbrB are repressors of other late growth functions but are essential for competence development. Sin is also a positive regulator for motility and autolysin production. These results suggest that AbrB and Sin act as developmental switches, enabling cells at the beginning of stationary growth to choose different developmental fates.
Bacillus subtilis↗
Impact of newer drugs and techniques on the quality of ambulatory anesthesia.
Recent pharmacologic and technologic advances in anesthesia and surgery allow outpatients with complex medical problems to undergo a wide variety of diagnostic and surgical procedures on an ambulatory basis. Increasingly, however, anesthesia practitioners, as well as pharmacy and therapeutic committees, are demanding proof that a new, more costly drug or medical device is superior to existing products in achieving its desired effect, is associated with fewer adverse effects, enhances efficiency, and reduces health care costs. The new field of pharmacoeconomics has emphasized the importance of cost-effectiveness analyses that consider both direct and indirect costs of newer drugs and therapeutic modalities. As new biomedical technology is introduced to facilitate the perioperative management of patients (e.g., computerized anesthesia information management systems), evidence that these systems enhance our ability to continue to provide high-quality, cost-effective health care will assume increasing importance. Limitations in health care resources necessitate a careful reevaluation of our clinical practices with respect to choice of drugs, supplies, equipment, and even discharge criteria. Ambulatory anesthesia and surgery will continue to increase because of the potential cost savings for patients undergoing elective operations on an outpatient basis. However, the challenge we face will be to continue to provide high-quality anesthesia care at a reduced cost. A careful examination of commonly accepted (but unproven) clinical practice patterns will be necessary to meet this challenge.
Ambulatory Surgical Procedures↗
The laryngeal mask airway for outpatient anesthesia.
The LMA has been commercially available since 1988, and in the United States since 1992. The device combines several advantages of endotracheal tubes and face masks and may be used in many situations where either device was previously used routinely. Its principal advantage is a clearer airway, without the morbidity associated with endotracheal intubation. Although not suitable for all patients and procedures, the LMA has become widely used in all other countries where it is available. Many of the surgical procedures for which the LMA is most suited are performed in outpatients, and we expect this device will soon become popular in carefully selected cases in this country.
Ambulatory Surgical Procedures↗
Cost-effectiveness analysis of antiemetic therapy for ambulatory surgery.
STUDY OBJECTIVE: To compare the relative cost-effectiveness ratios of (1) therapy with ondansetron, droperidol, and metoclopramide in the prevention of postoperative nausea and vomiting (PONV), and (2) prophylactic versus rescue therapy of PONV with these agents. DESIGN: Cost-effectiveness analysis based on the estimated costs of 12 mutually exclusive outcomes identified by decision analysis. SETTING: Computer model of outcome established using data extracted from published studies and a survey of current practice in two university-affiliated hospitals. PATIENTS: Patients undergoing operations associated with a high risk of PONV. INTERVENTIONS: The cost-effectiveness of prophylactic antiemetic therapy was compared among three drugs and also compared with limiting treatment to established PONV. MEASUREMENTS AND MAIN RESULTS: Direct costs included drug acquisition, drug delivery, equipment used in managing vomiting, and additional nursing time costs. Indirect costs included drugs and materials used to treat persistent nausea and/or vomiting and the side effects of prophylactic drugs, increased time spent in the postanesthesia care unit, unanticipated hospitalization, and lost earnings due to hospitalization. Separate models were created for patients with both nausea and vomiting and with isolated nausea. The total incremental costs associated with the prophylactic use of ondansetron, metoclopramide, and droperidol were $37.74, $28.43, and $18.17 per patient, respectively. The costs per emesis-free patient with the prophylactic use of ondansetron, metoclopramide, and droperidol, were $55.91, $71.08, and $30.15, respectively, and per nausea-free patient $68.93, $82.74, and $33.52, respectively. Prophylactic antiemetic therapy was cost-effective for operations with a high frequency of emesis, whereas treatment of established symptoms was more cost-effective when the frequency was lower. For ondansetron, prophylactic use was cost-effective only when the frequency of emesis exceeded 33%, whereas prophylactic droperidol was cost-effective even if the frequency was 10%. CONCLUSIONS: When drug costs, efficacy, and adverse events were all considered, prophylactic droperidol was more cost-effective than ondansetron, and both drugs were more cost-effective than metoclopramide. However, the expected frequency of PONV, as well as local drug acquisition costs, can significantly influence whether a particular antiemetic is cost-effective when given prophylactically or only as therapy for established PONV.
Ambulatory Surgical Procedures↗
Neonatal neurobehavioral characteristics as correlates of maternal alcohol use during gestation.
To determine the neurobehavioral consequences of alcohol use during different periods in gestation, we compared the behavior of 103 neonates born to women who: drank a mean of 12 ounces of absolute alcohol per week throughout pregnancy; drank a mean of 14 ounces of absolute alcohol and were otherwise comparable to the first group but stopped drinking in the second trimester, and never drank at all during pregnancy. Low socioeconomic status, predominantly black women applying for prenatal care at a large inner city hospital were recruited in the second trimester of pregnancy, and those reporting alcohol use were advised to stop drinking. Neurobehavioral evaluation with the Brazelton Neonatal Behavioral Assessment Scale was conducted at 3 days postnatal age. As a group, infants exposed to alcohol at any time during gestation were found to have significant alterations in reflexive behavior, less mature motor behavior, and an increased activity level in comparison to unexposed infants. Infants whose mothers stopped drinking in the second trimester were superior to those whose mothers continued to drink throughout pregnancy in observed state control, need for stimulation, motor tone, tremulousness, and asymmetries in reflexive behavior. These results indicate that characteristic damage does occur to the central nervous system of a fetus exposed to alcohol throughout pregnancy, and that exposure during only the early part of pregnancy also seems to have measurable effects. Multivariate analysis indicated that neither amount of alcohol used per week nor cigarette use contributed significantly to these effects on infant behavior.
Alcoholism↗
A sitting/companionship service for palliative care patients: Leicestershire, England.
Volunteers are vital to most UK hospices, performing wide-ranging duties. In our unit a carefully selected and trained group provides a professionally coordinated setting/companionship service for housebound patients. In this study we questioned their reasons for volunteering to "sit" and their evaluations of the training course. Six (of eight) completing the most recent course returned questionnaires. Five already were engaged in voluntary work, three within Leicestershire Hospice. They wanted to be "sitters" primarily to support the carers and to use their time constructively. They were aware of potential difficulties in "sitting" and considered the course had realistically acknowledged these and highlighted others that the volunteers had not contemplated, preparing them appropriately. Overall the course was valuable; all enthusiastically welcomed ongoing support and training.
Career Choice↗
Court action.
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Attitude of Health Personnel↗
The estimation of blood flow to hemodialyzers by bubble time.
Reliable estimation of blood flow to hemodialyzers is essential to the accurate prescription of therapy. Customarily an air bubble is timed as it traverses a racetrack of known volume and blood flow is calculated from the formula Qb (ml/min) = (volume/BT) (60 sec/min). The linearity of this relationship has recently been questioned. Air bubble velocities were statistically fit to measured blood flows over 6 hematocrit values. From the resulting relationship, Qb (ml/min) = 62 (vol/L) (L/BT)0.96, one can generate a table relating velocity to flow for clinical use.
Blood Flow Velocity↗
Developing a plan to evaluate the use of nursing conceptual frameworks.
Five hospitals in the Metropolitan Toronto area have introduced a nursing conceptual framework as the basis of practice in their agencies. A research team representing the hospitals and the University of Toronto has developed a comprehensive plan to evaluate the impact of using a nursing framework on nursing practice. This paper describes the selection of variables to be studied and the ways selected to measure them. A series of papers will follow describing the establishment of psychometric properties of the instruments and the results of the pre-test phase. Although this paper describes a process that began some time in the past, the authors have kept current the literature on the subject and the most current references are included in this paper.
Humans↗
The medical management of malignant disease.
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Antineoplastic Agents↗
Implementation of nursing conceptual models: observations of a multi-site research team.
The general acceptance by nursing of the nursing process as the methodology of practice enabled nurses to have a common grounding for practice, research and theory development in the 1970s. It has become clear, however, that the nursing process is just that--a process. What is sorely needed is the nursing content for that process and consequently in the past 10 years nursing theorists have further developed their particular conceptual models (CM). Three major teaching hospitals in Toronto have instituted a conceptual model (CM) of nursing as a basis of nursing practice. Mount Sinai Hospital has adopted Roy's adaptation model; Sunnybrook Medical Centre, Kings's goal attainment model; and Toronto General Hospital, Orem's self-care deficit theory model. All of these hospitals are affiliated through a series of cross appointments with the Faculty of Nursing at the University of Toronto. Two community hospitals, Mississauga and Scarborough General, have also adopted Orem's model and are related to the University through educational, community and interest groups. A group of researchers from these hospitals and the University of Toronto have proposed a collaborative project to determine what impact using a conceptual model will make on nursing practice. Discussions among the participants of this research group indicate that there are observations associated with instituting conceptual models that can be identified early in the process of implementation. These observations may be of assistance to others contemplating the implementation of conceptually based practice in their institution.
Attitude of Health Personnel↗
Eye Care--1. External examination.
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Eye Diseases↗