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Structural plasticity of enzymes dictates their function. Yet, our ability to rationally remodel enzyme conformational landscapes to tailor catalytic properties remains limited. Here, we report a computational procedure for tuning conformational landscapes that is based on multistate design of hinge-mediated domain motions. Using this method, we redesign the conformational landscape of a natural aminotransferase to preferentially stabilize a less populated but reactive conformation and thereby increase catalytic efficiency with a non-native substrate, resulting in altered substrate selectivity. Steady-state kinetics of designed variants reveals activity increases with the non-native substrate of approximately 100-fold and selectivity switches of up to 1900-fold. Structural analyses by room-temperature X-ray crystallography and multitemperature nuclear magnetic resonance spectroscopy confirm that conformational equilibria favor the target conformation. Our computational approach opens the door to targeted alterations of conformational states and equilibria, which should facilitate the design of biocatalysts with customized activity and selectivity., (© 2023. Springer Nature Limited.)

Purpose: Prenatal care is important for positive outcomes for both mother and infant. The traditional one-on-one method remains the most common. This study aimed to compare perinatal outcomes of patients attending group prenatal care with traditional prenatal care. Most previously published comparisons did not match for parity, a key predictor of perinatal outcome., Description: We collected perinatal outcome data for 137 group prenatal care patients and 137 traditional prenatal care patients, matched for contemporaneous delivery and parity, who delivered at our small rural hospital during 2015-2016. We included key public health variables, including the initiation of breastfeeding, and smoking at the time of delivery., Assessment: There was no difference between the two groups for maternal age or infant ethnicity, induced or augmented labor, preterm deliveries, APGAR scores less than 7, low birth weight, NICU admissions, or cesarean deliveries. Group care patients had more prenatal visits and were more likely to initiate breastfeeding and were less likely to report smoking at the time of delivery., Conclusion: In our rural population matched for contemporaneous delivery and parity, we found no difference in traditional perinatal outcome measures and that group care was positively associated with the key public health variables of not smoking and initiating breastfeeding. If future studies in other populations have similar findings, it may be wise to provide group care more widely to rural populations., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Birth mode has been implicated as a major factor influencing neonatal gut microbiome development, and it has been assumed that lack of exposure to the maternal vaginal microbiome is responsible for gut dysbiosis among caesarean-delivered infants. Consequently, practices to correct dysbiotic gut microbiomes, such as vaginal seeding, have arisen while the effect of the maternal vaginal microbiome on that of the infant gut remains unknown. We conducted a longitudinal, prospective cohort study of 621 Canadian pregnant women and their newborn infants and collected pre-delivery maternal vaginal swabs and infant stool samples at 10-days and 3-months of life. Using cpn 60-based amplicon sequencing, we defined vaginal and stool microbiome profiles and evaluated the effect of maternal vaginal microbiome composition and various clinical variables on the development of the infant stool microbiome. Infant stool microbiomes showed significant differences in composition by delivery mode at 10-days postpartum; however, this effect could not be explained by maternal vaginal microbiome composition and was vastly reduced by 3 months. Vaginal microbiome clusters were distributed across infant stool clusters in proportion to their frequency in the overall maternal population, indicating independence of the two communities. Intrapartum antibiotic administration was identified as a confounder of infant stool microbiome differences and was associated with lower abundances of Escherichia coli , Bacteroides vulgatus , Bifidobacterium longum and Parabacteroides distasonis . Our findings demonstrate that maternal vaginal microbiome composition at delivery does not affect infant stool microbiome composition and development, suggesting that practices to amend infant stool microbiome composition focus factors other than maternal vaginal microbes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Dos Santos, Pakzad, Albert, Elwood, Grabowska, Links, Hutcheon, Maan, Manges, Dumonceaux, Hodgson, Lyons, Mitchell-Foster, Gantt, Joseph, Van Schalkwyk, Hill and Money.)

Objective: Generations of colonialism, abuse, racism, and systemic trauma have contributed to Indigenous women in Canada bearing the greatest burden of substance use in pregnancy. Stigma associated with substance use in pregnancy translates into multiple barriers to women engaging in care. Care providers have key interactions that can act as a bridge or a barrier to care., Methods: Patient journey maps were created for women living with substance use (n = 3) and semi-structured interviews (n = 20) were performed to understand perceptions of maternity-care providers around women with substance use in pregnancy at a regional hospital in northern British Columbia., Results: Patient journey maps showed overall emotions of hurt, loss, judgment, and anger at their interface with health care during pregnancy. Providers described gaps in knowledge of substance use in pregnancy and harm reduction. Although care providers overall perceived themselves to be providing compassionate care without bias, the patient journey maps suggested profound judgment on behalf of providers., Conclusion: Ongoing cultural humility and trauma-informed care training along the continuum of care is critical to impacting discrepancies between perceived lack of bias and harm in patient interactions. Acknowledgment of systemic racism's impact on provision of maternity care is critical for health system change., (© 2021 The Authors. International Journal of Gynecology & Obstetrics published by John Wiley & Sons Ltd on behalf of International Federation of Gynecology and Obstetrics.)

Female-specific traumatic injury patterns have not been well researched and are potentially not well documented. Our aim was to examine the prevalence of breast hematomas (BHs) after blunt chest trauma, and to evaluate if there were risk factors associated with BH requiring intervention. A retrospective review from 2013 to 2018 was performed, identifying female patients ≥18 years sustaining blunt chest trauma. BH was defined as the presence of a collection of blood within the breast parenchyma, and clinically significant breast hematoma (CSBH) as BH requiring blood transfusion, surgical, or interventional radiology intervention. Univariate analysis was performed comparing CSBH with BH in terms of demographics, injury severity, antithrombotic agent use, and body mass index (BMI). Of 871 female patients meeting criteria, 59 (7%) had BH. Of these, 10 (17%) had CSBH (transfusion only, n = 3; angioembolization, n = 4; operation, n = 3). Compared to BH not requiring intervention, CSBH patients were older (mean age, 80 vs 69, P = .006), but had similar rates of motor vehicle crashes (90% vs 78%), seatbelt use (70% vs 71%), antiplatelet use (10% vs 12%), and anticoagulant use (10% vs 6%). Median Injury Severity Scores and median BMI (34 vs 34) were similar between the groups.

Background: The significance of external signs (EST) and signs or symptoms of trauma (SS) after ground level falls or found down (GLF/FD) is unclear. We hypothesized that EST and SS were associated with injury., Methods: Patients with GLF/FD were retrospectively studied. SS was defined as having any EST, tenderness, or subjective complaint. Outcomes were any significant finding (SF) and Injury Severity Score (ISS) > 8. Diagnostic accuracy of EST and SS were assessed with positive and negative likelihood ratios (LR+, LR-)., Results: Of 578 patients, 66% and 95% had EST and SS respectively. For EST, LR+ and LR-were 1.14 and 0.76 (SF), and 1.21 and 0.64 (ISS>8). For SS, LR+ and LR-were 1.07 and 0.19 (SF), and 1.03 and 0.49 (ISS>8)., Conclusion: EST lacked sufficient diagnostic accuracy for SF and ISS>8. Lack of SS was reasonably accurate in ruling out SF but not ISS>8. Triage utilizing EST alone for GLF/FD is not useful., Competing Interests: Declaration of competing interest There are no conflicts of interest to report., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Introduction: Women are under-represented in the surgical disciplines and gender bias is believed to play a factor. We aimed to understand the gender distribution of membership, leadership opportunities, and scientific contributions to annual trauma professional meetings as a case study of gender issues in trauma surgery., Methods: Retrospective collection of membership, leadership, presentation and publication data from 2016 to 2018 Trauma/Acute Care Surgery/Surgical Critical Care (TACSCC) Annual Meetings. Gender was assigned based on self-identification in demographic information, established relationships, or public sources., Results: Women remain under-represented with only 28.1% of those ascertaining American Board of Surgery certification in critical care self-identifying as female. The proportion of female members in Eastern Association for the Surgery of Trauma (EAST) was comparable (29.4%), slightly lower for Western Trauma Association (WTA) (19.0%), and lowest for American Association for the Surgery of Trauma (AAST) (12.8%, p<0.05). In contrast, AAST had the highest proportion of female participants in executive leadership (AAST 32.5%, WTA 19.0%, EAST 18.8%) and WTA the highest for committee chairs (WTA 33.3%, AAST 27.8%, EAST 20.5%). AAST had the most significant increase in executive leadership during the last 3 years (AAST 28.6% to 41.6%). Invited lectureships, masters, panelists and senior author scientific contributions demonstrated the largest gap of academic representation of female TACSCC surgeons., Conclusion: Fewer women than men pursue careers in the trauma field. Continuing to provide mentorship, leadership, and scientific recognition will increase gender diversity in TACSCC. We must continue to promote, sponsor, recognize, invite, and elect 'her'., Level of Evidence: III, Epidemiology., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: We sought to determine if clinician suspicion of injury was useful in predicting injuries found on pan-body computed tomography (PBCT) in clinically intoxicated patients., Methods: We prospectively enrolled awake, intoxicated patients with low-energy mechanism of injury. For each of four body regions (head/face, neck, thorax and abdomen/pelvis), clinician suspicion for injury was recorded as "low index" or "more than a low index". The reference standard was the presence of any pre-defined significant finding (SF) on CT. Sensitivity, specificity, positive (LR+) and negative (LR-) likelihood ratios were calculated., Results: Enrollment of 103 patients was completed. Sensitivity, specificity, LR+ and LR-for clinician index of suspicion were: 56%, 68%, 1.75, 0.64 (head/face), 50%, 92%, 6.18, 0.54 (neck), 10%, 96%, 2.60, 0.94 (thorax) and 67%, 93%, 9.56, 0.36 (abdomen/pelvis)., Conclusion: Clinician judgement was most useful to guide need for CT imaging in the neck and abdomen/pelvis. Routine PBCT may not be necessary., Summary: For awake, stable intoxicated patients after falls and assaults, clinician index of suspicion was most useful to guide the need for CT imaging in the neck and abdomen/pelvis. Our findings support selective use of CT if the index of suspicion is low. Routine PBCT may not be necessary., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Catalyst transfer polycondensation is the only method to prepare π-conjugated polymers in a chain-growth manner, yet several aspects that underlie this polymerization are not fully understood. Here, we investigate the nickel-catalyzed polymerization mechanisms of a series of thiophene monomers bearing different halogen functionalities (Cl, Br, I). We have discovered the significant role that halogens and magnesium salts play in this polymerization. More specifically, the catalyst resting state changes depending on the type of halogenated monomer. For chlorinated monomers a mixture of Ni(ii)-dithienyl and dissociated Ni(phosphine) complexes are the resting states, which results in uncontrolled polymerization. For brominated monomers, a Ni(ii)-dithienyl complex is the resting state, which leads to controlled polymerization. For iodinated monomers, a Ni(ii)-thienyl iodide complex is the resting state, and notable inhibition by magnesium salt by-products is observed. The catalyst resting state changes to a Ni(ii)-dithienyl complex when a turbo Grignard reagent ( i -PrMgCl·LiCl) is used. These findings are used to guide the design of a new monomer, 2-bromo-3-(2-ethylhexyl)-5-iodotellurophene, which enables the first controlled polymerization of a tellurophene monomer containing a sterically encumbered 2-ethylhexyl side chain. These insights are crucial for deepening the mechanistic understanding of Kumada cross coupling reactions and the controlled synthesis of π-conjugated polymers.

Purpose: This preliminary study explores Ugandan men's knowledge and attitudes about human papillomavirus (HPV), cervical cancer, and screening., Methods: A local physician led an education session about cervical cancer for 62 men in Kisenyi, Kampala in Uganda. Trained nurse midwives administered surveys to assess knowledge and attitudes before and after the education session., Results: From the pre-education survey, only 24.6% of men had heard of HPV previously, and 59% of men had heard of cervical cancer. Posteducation, 54.5% of men believed only women could be infected with HPV and 32.7% of men believed antibiotics could cure HPV. Despite their limited knowledge, 98.2% of men stated they would support their partners to receive screening for cervical cancer, and 100% of men surveyed stated they would encourage their daughter to get the HPV vaccine if available., Conclusions: Knowledge of HPV and cervical cancer among Ugandan men is low. Even after targeted education, confusion remained about disease transmission and treatment. Ongoing education programs geared toward men and interventions to encourage spousal communication about reproductive health and shared decision making may improve awareness of cervical cancer prevention strategies.

Background: Cervical cancer is the leading cause of cancer death for women in Uganda, despite the potential for prevention through organised screening. Community-based self-collected human papillomavirus (HPV) testing has been proposed to reduce barriers to screening., Objective: Our objective was to evaluate the cost-effectiveness of the Advances in Screening and Prevention of Reproductive Cancers (ASPIRE) trial, conducted in Kisenyi, Uganda in April 2014 (n=500). The trial compared screening uptake and compliance with follow-up in two arms: (1) community-based (ie, home or workplace) self-collected HPV testing (facilitated by community health workers) with clinic-based visual inspection with acetic acid (VIA) triage of HPV-positive women ('HPV-VIA') and (2) clinic-based VIA ('VIA'). In both arms, VIA was performed at the local health unit by midwives with VIA-positive women receiving immediate treatment with cryotherapy., Design: We informed a Monte Carlo simulation model of HPV infection and cervical cancer with screening uptake, compliance and retrospective cost data from the ASPIRE trial; additional cost, test performance and treatment effectiveness data were drawn from observational studies. The model was used to assess the cost-effectiveness of each arm of ASPIRE, as well as an HPV screen-and-treat strategy ('HPV-ST') involving community-based self-collected HPV testing followed by treatment for all HPV-positive women at the clinic., Outcome Measures: The primary outcomes were reductions in cervical cancer risk and incremental cost-effectiveness ratios (ICERs), expressed in dollars per year of life saved (YLS)., Results: HPV-ST was the most effective and cost-effective screening strategy, reducing the lifetime absolute risk of cervical cancer from 4.2% (range: 3.8%-4.7%) to 3.5% (range: 3.2%-4%), 2.8% (range: 2.4%-3.1%) and 2.4% (range: 2.1%-2.7%) with ICERs of US$130 (US$110-US$150) per YLS, US$240 (US$210-US$280) per YLS, and US$470 (US$410-US$550) per YLS when performed one, three and five times per lifetime, respectively. Findings were robust across sensitivity analyses, unless HPV costs were more than quadrupled., Conclusions: Community-based self-collected HPV testing followed by treatment for HPV-positive women has the potential to be an effective and cost-effective screening strategy., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Background: The impact of preoperative percutaneous endoscopic gastrostomy (PEG) tube placement in patients undergoing esophagectomy is uncertain., Methods: A retrospective review was performed in consecutive patients who underwent esophagectomy. Patients were divided into groups based on whether or not they had preoperative PEG placement., Results: One hundred seventeen patients were studied, 102 without (PEG-) and 15 with PEG+ before PEG tube placement. The overall morbidity and mortality rates were 38% and 3%, respectively. The use of a gastric conduit was similar between groups (94% PEG- vs 87% PEG+, P = .27), and the presence of a PEG before PEG tube placement was not prohibitive in any case. Anastomotic leak rates were similar between groups (11% PEG- vs 15% PEG+, P = .65), and there were no leaks from previous PEG sites., Conclusion: It appears that preoperative PEG tube placement has no adverse effect on the performance of esophagectomy and may be considered in highly selected patients with poor nutritional status., (Copyright © 2014 Elsevier Inc. All rights reserved.)

A mixed-method study was used to characterize the occupational stress, health status, and coping strategies of 104 members of the Alabama Veterinary Technician Association. A Web-based survey was used to administer three validated and reliable instruments to gather the quantitative data, and interviews were conducted to gather qualitative data. Quantitative and qualitative data validated each other in all aspects of mental health, indicating that veterinary support staff's mental health status was low. Participants' mental health scores were lower than the US norm of 50, and a correlation between health status and occupational stressors indicated that those with higher perceived stress had lower mental and physical health. Interviews supported this finding. The results suggest that workload, death and dying, and conflict with veterinarians were prominent sources of stress and that veterinary support staff experience high stress that affects their health. Coping strategies were found to be related to mental health status, and those used by this workforce have been linked to negative outcomes. This study's findings indicate that staff health may have negative economic implications for practice owners and staff members.

Older adults have been shown to exhibit a positivity effect in processing of emotional stimuli, seemingly focusing more on positive than negative information. Whether this reflects purposeful changes or an unintended side effect of declining cognitive abilities is unclear. For the present study, older adults displaying a wide range of cognitive abilities completed measures of attention, visual, and verbal memory; executive functioning and processing speed; as well as a socioemotional measure of time perspective. Regression analyses examined the ability of these variables to predict neural responsivity to select emotional stimuli as measured with the late positive potential (LPP), an event-related brain potential (ERP). Stronger cognitive functioning was associated with higher LPP amplitude in response to negative images (i.e., greater processing). This does not support a voluntary avoidance of negative information processing in older adults for this particular measure of attentional allocation. A model is proposed to reconcile this finding with the extant literature that has demonstrated positivity effects in measures of later, controlled attentional allocation.

Temporal processing, or processing time-related information, appears to play a significant role in a variety of vital psychological functions. One of the main confounds to assessing the neural underpinnings and cognitive correlates of temporal processing is that behavioral measures of timing are generally confounded by other supporting cognitive processes, such as attention. Further, much theorizing in this field has relied on findings from clinical populations (e.g., individuals with schizophrenia) known to have temporal processing deficits. In this study, we attempted to avoid these difficulties by comparing temporal processing assessed by a pre-attentive event-related brain potential (ERP) waveform, the mismatch negativity (MMN) elicited by time-based stimulus features, to a number of cognitive functions within a non-clinical sample. We studied healthy older adults (without dementia), as this population inherently ensures more prominent variability in cognitive function than a younger adult sample, allowing for the detection of significant relationships between variables. Using hierarchical regression analyses, we found that verbal memory and executive functions (i.e., planning and conditional inhibition, but not set-shifting) uniquely predicted variance in temporal processing beyond that predicted by the demographic variables of age, gender, and hearing loss. These findings are consistent with a frontotemporal model of MMN waveform generation in response to changes in the temporal features of auditory stimuli., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Objective: Hypertension and other noncommunicable diseases represent a growing threat to low/middle-income countries (LMICs). Mobile health technologies may improve noncommunicable disease outcomes, but LMICs lack resources to provide these services. We evaluated the efficacy of a cloud computing model using automated self-management calls plus home blood pressure (BP) monitoring as a strategy for improving systolic BPs (SBPs) and other outcomes of hypertensive patients in two LMICs., Subjects and Methods: This was a randomized trial with a 6-week follow-up. Participants with high SBPs (≥140 mm Hg if nondiabetic and ≥130 mm Hg if diabetic) were enrolled from clinics in Honduras and Mexico. Intervention patients received weekly automated monitoring and behavior change telephone calls sent from a server in the United States, plus a home BP monitor. At baseline, control patients received BP results, hypertension information, and usual healthcare. The primary outcome, SBP, was examined for all patients in addition to a preplanned subgroup with low literacy or high hypertension information needs. Secondary outcomes included perceived health status and medication-related problems., Results: Of the 200 patients recruited, 181 (90%) completed follow-up, and 117 of 181 had low literacy or high hypertension information needs. The median annual income was $2,900 USD, and average educational attainment was 6.5 years. At follow-up intervention patients' SBPs decreased 4.2 mm Hg relative to controls (95% confidence interval -9.1, 0.7; p=0.09). In the subgroup with high information needs, intervention patients' average SBPs decreased 8.8 mm Hg (-14.2, -3.4, p=0.002). Compared with controls, intervention patients at follow-up reported fewer depressive symptoms (p=0.004), fewer medication problems (p<0.0001), better general health (p<0.0001), and greater satisfaction with care (p≤0.004)., Conclusions: Automated telephone care management plus home BP monitors can improve outcomes for hypertensive patients in LMICs. A cloud computing model within regional telecommunication centers could make these services available in areas with limited infrastructure for patient-focused informatics support.

Unlabelled: BACKGROUND/STUDY CONTEXT: An emotion recognition task that morphs emotional facial expressions from an initial neutral expression to distinct increments of the full emotional expression was administered to 482 individuals, 20 to 89 years of age., Methods: Participants assessed six basic emotions at 25%, 50%, 75%, and 100% of the full facial expression., Results: Participants in the three oldest age groups (60s, 70s, and 80s) demonstrated decreased performance for the recognition of the fear, anger, and sad emotions. Increased age was associated with increased recognition rates for the disgust expression, whereas no age effect was detected for the happy and surprise expressions. Covariate analyses revealed age effects were reduced by processing speed, but were unaffected by decision-making ability. The effects of age on individual emotions and levels of presentation are discussed., Conclusion: These findings suggest that age has the greatest impact on the recognition of the sad emotion and the greatest age effect at the 50% level of presentation across the adult life span.

Gallstones develop in approximately 10% to 15% of the US population and represent one of the most common and most costly of all digestive diseases. Studies investigating gallstones' natural history have shown that gallstone-related complications arise at a rate of approximately 1% per year in asymptomatic patients and 2% per year in patients who already have symptoms. Patients can have any of multiple presentations with gallstone-related problems along a continuum of health threats from intermittent biliary colic to septic shock from ascending infections. In most clinical situations in which the patient's gallstone symptoms are either recurrent or have caused complications, cholecystectomy remains the procedure of choice. Laparoscopic cholecystectomy, first performed in the mid-1980s, has quickly become the gold standard in the US. For clinicians who perform abdominal procedures, the literature is consistent in advocating cholecystectomy for gallstones found incidentally during other abdominal procedures.

Background: In clinical practice, mitochondrial disease is seldom considered until a variable combination of seizures, alteration in tone, muscle weakness, and developmental problems is evident. However, it is not uncommon for one symptom to occur in isolation and dominate the clinical phenotype. We report six patients from two families where dystonia was the principal clinical manifestation. A mitochondrial etiology was considered in each case because of the association of dystonia with other less prominent clinical features such as epilepsy., Methods: Histochemical and biochemical analyses were undertaken in skeletal muscle biopsies from individuals in both families. Sequencing of skeletal muscle mtDNA was also performed and suspected mutations were quantified by hot last cycle PCR-RFLP or primer extension assay. Functional consequences of one of the mutations were investigated by measurement of steady state levels of mitochondrial tRNA., Results: Two distinct mitochondrial pathologies were identified: a novel, homoplasmic mitochondrial tRNA(Cys) (MTTC) mutation and the primary, m.11778G>A Leber hereditary optic neuropathy (LHON) mutation. The mild nature of both mutations has permitted very high levels of mutated mtDNA to accumulate. Patients with the mutation in the MTTC gene have no wild type mtDNA detectable and although the LHON mutation is heteroplasmic in the patients we report, it is commonly observed to be homoplasmic., Conclusions: The mitochondrial etiology identified in these patients emphasizes the pathologic potential of homoplasmic mutations and has important implications for the investigation and genetic counseling of families where dystonia is the principal clinical feature. We advocate that mitochondrial disease should be given serious consideration in patients with familial, progressive dystonia, particularly when additional neurologic features such as epilepsy are present.

Several factors influence dementia caregiver desire to institutionalize; however, little is known about differences in caregivers who desire institutionalization versus those who do not. The current study compares predictors of desire to institutionalize in dementia caregivers. Seventy-two caregivers completed the Desire to Institutionalize Scale (DIS) and several psychosocial measures, including burden, dementia knowledge, self-efficacy, depression, health, care recipient daily functioning and memory/behavior problems, family functioning, and social support. Based on DIS responses, caregivers were divided into No DI versus DI groups. DI caregivers had significantly higher burden, greater dementia knowledge, more family dysfunction, and decreased social support compared with No DI caregivers. Findings emphasize the importance of caregiver and family relationship variables in DIS, suggesting potentially modifiable targets for caregiver interventions. Dementia knowledge was associated with higher DIS, suggesting that educational programs alone may not be helpful to delay institutionalization.

Nasal allergen challenge of patients with allergic rhinitis results in increased numbers of inflammatory cells and increased production of pro-inflammatory cytokines including interleukin 5 (IL-5). We report a sensitive, noninvasive method to measure changes in the amount of mRNA for IL-5 in nasal epithelium and have used this method to detect alterations of IL-5 mRNA from patients undergoing a nasal allergen challenge. Ten grass or ragweed allergic adults were challenged out of season with appropriate pollen extracts at sufficient dose to give a rhinitis total symptom score of 5 on a scale of 12. After allergen exposure, symptoms were recorded hourly. At 0, 3, and 6 h after allergen exposure, secreted proteins were collected on filter paper strips and two superficial scrapings of nasal epithelium were obtained. The scrapings of epithelium were immediately immersed in 100 microl of RNAlater (Ambion, Austin, TX) and stored at 4 degrees C for up to 1 month without loss of RNA quality. Total RNA was isolated and RT-PCR was performed. cDNA for IL-5 was then measured by real-time fluorescence quantitative PCR with Pre-Developed TaqMan Assay Reagents (PE Biosystems, Foster City, CA). Sufficient RNA was isolated from eight subjects to measure IL-5 mRNA. Data were normalized for content of ribosomal RNA. The relative amount of cDNA for IL-5 was calculated by comparison with internal standards prepared from phytohemagluttinin-stimulated peripheral blood mononuclear cells. Messenger RNA for IL-5 was increased 8.7+/-2.7-fold at 3 h (p<0.01) and 39.5+/-20.9-fold at 6 h (p<0.01). Increased IL-5 mRNA levels at 6 h closely correlate with total symptom scores at 6 h (r=0.88; p=0.007). IL-5 protein was measured by ELISA in eluates from the filter papers. At 6 h, there was increased IL-5 protein (7.7+/-2.8 ng/ml) compared with time zero (1.8+/-0.5 ng/ml) (p=0.02). The levels of IL-5 protein did not correlate significantly with the symptoms score or with changes in the levels of IL-5 protein with IL-5 mRNA. These data show that changes in IL-5 mRNA in patients with allergic rhinitis undergoing an allergen challenge correlate with total symptom scores better than changes in IL-5 protein eluted from filter paper. Furthermore, these changes can be measured quantitatively in very small amounts of tissue.

The use of multiple in vitro reference methods to validate three-dimensional (3-D) echocardiographic techniques makes comparison difficult. In an attempt to establish a reference standard, we studied precision, accuracy, and feasibility of a true left ventricular (LV) volume measurement in six dog heart specimens using three techniques, called fluid, sheath, and cast. LV volumes ranged from 30 to 105 mL. Intraobserver variability was minimal in all combinations (1.26% to 2.8%) with a statistically insignificant tendency to higher values in the cast method. The cast method, however, exhibited significantly higher interobserver variability (5.78%) as compared to that ranging from 1.47% to 1.59% in the remaining two techniques. Regression analysis demonstrated high correlations among the three techniques assessed by 95% confidence limits and correlation coefficient (R(2) > 0.98, P < 0.01). Mean differences among the techniques (0.12 to 1.08 mL) were not significant. The fluid technique was easy to perform. The sheath technique required some practice. The cast method was sensitive to accurate preparation of a gelatin mixture. We conclude that the fluid and sheath techniques are precise, accurate, and feasible. We recommend their use as reference standards in laboratory LV volume measurement. Validation 3-D echocardiographic studies using either of these two techniques will be comparable. Although the accuracy of the cast technique is excellent, its lower precision makes it a second choice. It could be used in cases where an LV cavity cast is required and higher interobserver variability is acceptable.

Use of the expert system as a tool for clinical decision support for students and practitioners of nursing is a subject of much discussion and developmental activity. A prototype of a nursing expert system was designed for use in a simulated laboratory environment to provide nursing students with decision support in identifying and managing common postoperative complications. Formative evaluation of the system with associate and baccalaureate nursing students elicited positive response and formed the basis for ongoing program refinement. The practicing nurse of the future must understand expert system use in order to consider the implications and potential of such a clinical tool in nursing practice.