Dissection of the promoter region of the inositol 1,4,5-trisphosphate receptor gene, itr-1, in C. elegans: a molecular basis for cell-specific expression of IP3R isoforms.

Inositol 1,4,5-trisphosphate receptors in Caenorhabditis elegans are encoded by a single gene, itr-1. This provides a powerful system in which to dissect the mechanisms that control the tissue-specific expression of molecules that determine the specificity of calcium signalling. We first identified the Caenorhabditis briggsae orthologue of itr-1, Cbitr-1. Comparison of the two itr-1 genes revealed that the chromosomal organisation, gene structure and predicted cDNA and protein sequences were all conserved. The conserved gene structure supports the hypothesis that the itr-1 gene has three promoters, each of which gives rise to an alternative mRNA and hence unique protein. To test this and to identify the roles of the three putative promoters (pA, pB and pC) in regulating itr-1 expression we fused each promoter to the green fluorescent protein gene and identified their expression patterns. Introduction of these transgenes into C. elegans identified unique and defined patterns of green fluorescent protein expression directed by each promoter: pA directs expression in the pharyngeal terminal bulb, the rectal epithelial cells and vulva; pB directs expression in the motor neurone PDA, the amphid socket cells and the spermatheca; pC directs expression in the spermathecal valve, uterine sheath cells, pharyngeal isthmus and intestine. Thus tissue-specific expression of itr-1 variants is directed by three promoters and this results in adjacent cells in the same tissue containing different inositol trisphosphate receptor isoforms. Within pA, four short regions (pA-A to pA-D) of sequence conservation between C. elegans and C. briggsae were identified. Deletion analysis demonstrated that the region containing pA-C is required for expression in the terminal bulb and rectal epithelial cells and the region containing pA-D is required for expression in the vulva. pA-C includes sequences similar to the binding sites for transcription factors that have been demonstrated to be important in pharyngeal development and gene expression.

Quantitative real-time monitoring of dryer effluent using fiber optic near-infrared spectroscopy.

This paper describes a method for real-time quantitation of the solvents evaporating from a dryer. The vapor stream in the vacuum line of a dryer was monitored in real time using a fiber optic-coupled acousto-optic tunable filter near-infrared (AOTF-NIR) spectrometer. A balance was placed in the dryer, and mass readings were recorded for every scan of the AOTF-NIR. A partial least-squares (PLS) calibration was subsequently built based on change in mass over change in time for solvents typically used in a chemical manufacturing plant. Controlling software for the AOTF-NIR was developed. The software collects spectra, builds the PLS calibration model, and continuously fits subsequently collected spectra to the calibration, allowing the operator to follow the mass loss of solvent from the dryer. The results indicate that solvent loss can be monitored and quantitated in real time using NIR for the optimization of drying times. These time-based mass loss values have also been used to calculate "dynamic" vapor density values for the solvents. The values calculated are in agreement with values determined from the ideal gas law and could prove valuable as tools to measure temperature or pressure indirectly.

Predictors of depression symptoms in pregnant adolescents.

The purpose of this study involving a cross-cultural group of single, pregnant adolescents was to examine the association of depression with self-esteem, social support, discomforts of pregnancy, and selected sociodemographic variables. The sample comprised 62 pregnant adolescents recruited from a residential maternity home. Subjects ranged in age from 14 to 20 years (mean 16.67 years) and were predominantly Hispanic and black. All subjects completed the Center for Epidemiological Studies Depression Scale, Coopersmith's Self-Esteem Inventory, a physical discomfort checklist, and a sociodemographic questionnaire. A high level of depression symptoms was reported by the majority of participants. Nearly two thirds of the young women reported adequate levels of emotional support; however, the remaining subjects claimed inadequate levels. Results of the multiple regression analyses revealed that, of the predictor variables investigated, only the total self-esteem score was statistically significant (p = 0.0001) and explained 32.6% of the variance. In further statistical analysis a multifactor analysis of variance found social support to be a significant variable influencing depression. On the basis of these results, several recommendations for assessment and intervention with similar groups of pregnant adolescents are suggested, including screening for depression symptoms and development of treatment programs for affected youth.

Evidence-based prenatal care visits: when less is more.

Traditionally, low-risk pregnant women in the United States who participate in prenatal care have been scheduled for approximately 14-16 prenatal visits, which is the schedule recommended by the American College of Obstetricians and Gynecologists. In 1989, an expert panel convened by the United States Department of Health and Human Services proposed a reduced frequency prenatal visit schedule for low-risk, healthy women based on the timing of specific tests or events that occur in pregnancy. Available evidence shows no adverse effect on maternal or neonatal outcomes for low-risk pregnant women who follow a reduced visit schedule, making it a highly important consideration for pregnant women and their health care providers. Other important aspects of prenatal care, especially related to adequacy and content, will be explored in-depth in a future segment of this series on evidence-based prenatal care.

Labor and delivery nurses' attitudes toward intermittent fetal monitoring.

Fetal monitoring is a routine procedure overseen by labor and delivery nurses and upon which they exert considerable influence. There is a discrepancy, however, between the type of fetal monitoring routinely used and the evidence provided by current research and professional organization recommendations. This study provides the first look at labor and delivery nurses' attitudes toward fetal monitoring in more than 20 years. A descriptive, correlational study was conducted at five southeastern Michigan hospitals to evaluate attitudes toward intermittent fetal monitoring and the effect of selected demographic variables on their attitudes. Of the labor and delivery nurses who participated (N = 145), 72.4% agreed that intermittent fetal monitoring should be the standard of care. Although 87% of the respondents stated that they were willing to provide intermittent monitoring, 53.9% indicated that nurse/patient ratios were a problem in providing this service. Nurses' attitudes were significantly influenced by education level (P = .004), and 48% were unsure about current research findings related to intermittent auscultation. Nurses have a positive attitude toward intermittent monitoring, although safe nurse/patient ratios and clear policies need to be addressed. Lack of knowledge regarding the current evidence and other barriers may contribute to intermittent auscultation not being used routinely, despite the fact that its use for women of low obstetrical risk is supported by current research and professional organizations.

Evaluation of a reduced-frequency prenatal visit schedule for low-risk women at a free-standing birthing center.

OBJECTIVE: to evaluate the effectiveness of a reduced-frequency prenatal visit schedule by comparing perinatal outcomes, anxiety and maternal satisfaction with prenatal care. METHODS: pregnancy outcomes of infant and maternal morbidity and mortality, anxiety and satisfaction for 81 women receiving prenatal care at a free-standing birthing center according to either an alternative prenatal care visit schedule (APCVS) (n = 43) or the traditional prenatal care visit schedule (TPCVS) (n = 38) were examined in this prospective randomized study. Upon entry into prenatal care, all women were of low obstetrical risk status. RESULTS: major findings revealed no significant differences in selected perinatal outcomes between the two study groups. Women in the APCVS group reported significantly higher levels of satisfaction than women in the TPCVS group on both the satisfaction with provider subscale (F = 5.74, P = .02) and the satisfaction with the prenatal care system subscale (F = 2.01, P = .04). There were no statistically significant differences found in anxiety scores between women in the two study groups. CONCLUSIONS: low-risk women who followed the reduced-frequency visit schedule experienced no difference in perinatal outcomes or anxiety. Women in the reduced-frequency (APCVS) group reported an increased level of satisfaction with both provider and the prenatal care system.

Survival of nurse-managed centers: the importance of cost analysis.

Despite the explosive growth in nurse-managed centers (NMC) in the past 20 years, most have been unable to achieve financial self-sufficiency, and many have closed. Combining costing techniques with outcome measures provides essential information needed by NMC for making operating decisions and for marketing NMC performance. These outcome data can be persuasive to policy makers and institutional decision makers and are crucial for NMC to improve their competitiveness in the health care market place.

A comparison of simple tests to distinguish cerebrospinal fluid from saline.

PURPOSE: This prospective study was undertaken to determine if anesthesiologists of different levels of training, using simple tests, can distinguish cerebrospinal fluid (CSF) from saline. METHODS: Thirty-two anaesthetists, divided into four groups, dependent upon levels of training, participated in the study. Each was asked to distinguish saline from an artificial CSF solution using four different tests: tactile temperature, glucose strip, pH strip, and turbidity when mixed with thiopental. RESULTS: Participants identified cerebrospinal fluid correctly with 84% accuracy using the temperature test, 97% using the glucose test, 91% using the pH test, and 50% using the thiopentone test. More than half of the participants guessed while using the thiopentone test, and those who did not guess were only 47% accurate. CONCLUSION: Level of training made no difference in distinguishing CSF from saline. No one test was 100% reliable. Clinical utility of the thiopentone test appears to be limited. The temperature, glucose, and pH tests, when used together, appear to be a useful way of distinguishing CSF from saline.

Using cognitive theory to improve nurse practitioners' anticipatory guidance with contraceptive pill users.

Community health nurse practitioners are often the major contraceptive counselors who may use anticipatory guidance to help clients' use behaviors. Because pregnancy rates during typical use are much higher than during "perfect" use, more effective anticipatory guidance could help improve use behaviors. Principles of cognitive theory were used to explore the implications of specific words and approaches associated with discussing young adults' contraceptive use. Qualitative results are reported here, and potential implications are made for nurse practitioners' anticipatory guidance related to contraceptive use.

Obstetric postanesthesia care unit stays: reevaluation of discharge criteria after regional anesthesia.

BACKGROUND: Obstetric patients may have long postanesthesia care unit (OB-PACU) stays after surgery because of residual regional block or other conditions. This study evaluated whether modified discharge criteria might allow for earlier discharge without compromising patient safety. METHODS: Data were prospectively collected for 6 months for all patients (N=358) who underwent cesarean section or tubal ligation and recovered in the OB-PACU. Regional anesthesia was used in 94% of patients. The duration of anesthesia and PACU stays, the presence and treatment of events in the PACU, and the regression of neural blockade were recorded. Discharge from the OB-PACU required a 60-min minimum stay, stable vital signs, adequate analgesia, and ability to flex the knees. After completion of prospective data collection, events that kept patients in the PACU after 60 min were reevaluated as to whether patients needed to stay in the PACU for medical reasons. "Needed to stay" events included bleeding, cardiorespiratory problems, sedation, dizziness, and pain. "Safe to leave" conditions included pruritus, nausea, and residual neural blockade. The cumulative duration of OB-PACU stays not clearly justifiable for medical reasons was calculated. RESULTS: Residual block and spinal opioid side effects accounted for the majority of "unnecessary" stays. Annually, 429 h of PACU time could have been saved using the revised criteria. Complications did not develop subsequently in any patient deemed "safe to leave." CONCLUSIONS: In many obstetric patients, the duration of PACU stays could safely be shortened by continuing observation in a lower-acuity setting. This may result in greater flexibility and more efficient use of nursing personnel.

The Caenorhabditis elegans orthologue of the human gene responsible for spinal muscular atrophy is a maternal product critical for germline maturation and embryonic viability.

Spinal muscular atrophy (SMA) is a common disorder characterized by loss of lower motor neurones of the spinal cord. The disease is caused by mutations in the survival motor neurone ( SMN ) gene. SMN is ubiquitously expressed and evolutionarily conserved, and its role in RNA processing has been well established. However, these properties do not explain the observed specificity of motor neurone death. To gain further insight into the function of SMN, we have isolated and characterized the Caenorhabditis elegans orthologue of the SMN gene ( CeSMN ). Here we show that CeSMN is transmitted maternally as a predominantly nuclear factor, which remains present in all the blastomeres throughout embryonic development and onwards into adulthood. In adult nematodes, a CeSMN-green fluorescent protein fusion protein is expressed in a number of cell types including the germline. Both disruption of the endogenous CeSMN function and overexpression of the gene result in a severe decrease in the number of progeny and in locomotive defects. In addition, its transient knockdown leads to sterility caused by a defect in germ cell maturation. The expression pattern and functional properties so far observed for CeSMN, together with its unusual behaviour in the germline, indicate that SMN may be involved in specific gene expression events at these very early developmental stages. We have also identified a deletion in the CeSMN promoter region in egl-32. This mutant may become a useful genetic tool with which to explore regulation of CeSMN and hence provide possible clues for novel therapeutic strategies for SMA.