Whole-House Emission Rates and Loss Coefficients of Formaldehyde and Other Volatile Organic Compounds as a Function of the Air Change Rate.

Whole-house emission rates and indoor loss coefficients of formaldehyde and other volatile organic compounds (VOCs) were determined from continuous measurements inside a net-zero energy home at two different air change rates (ACHs). By turning the mechanical ventilation on and off, it was demonstrated that formaldehyde concentrations reach a steady state much more quickly than other VOCs, consistent with a significant indoor loss rate attributed to surface uptake. The first order loss coefficient for formaldehyde was 0.47 ± 0.06 h-1 at 0.08 h-1 ACH and 0.88 ± 0.22 h-1 at 0.62 h-1 ACH. Loss rates for other VOCs measured were not discernible, with the exception of hexanoic acid. A factor of 5.5 increase in the ACH increased the whole-house emission rates of VOCs but by varying degrees (factors of 1.1 to 3.8), with formaldehyde displaying no significant change. The formaldehyde area-specific emission rate (86 ± 8 µg m-2 h-1) was insensitive to changes in the ACH because its large indoor loss rate muted the impact of ventilation on indoor air concentrations. These results demonstrate that formaldehyde loss rates must be taken into account to correctly estimate whole-house emission rates and that ventilation will not be as effective at reducing indoor formaldehyde concentrations as it is for other VOCs.

Role of Organics in Regulating ClNO2 Production at the Air-Sea Interface.

We report measurements of the product yield for nitryl chloride (ClNO2) production following the reactive uptake of dinitrogen pentoxide (N2O5) to a wide variety of ambient seawater samples as well as seawater mimics. The ClNO2 yield, as measured for ambient seawater collected from both coastal and open ocean waters, was found to be both insensitive to chlorophyll-a, a marker for biological activity, and significantly lower (0.16-0.30) than that expected for equivalent salt-containing solutions (0.82 ± 0.05). Suppression in the ClNO2 yield can be induced by the addition of aromatic organic compounds (e.g., phenol and humic acid) to synthetic seawater matrices. In the case of phenol, surface tension measurements reveal that the surface phenol:chloride ratio can be enhanced by more than a factor of 100 as compared to bulk ratios for subtle changes in surface tension (<1.5 mN m(-1)), providing a mechanism to suppress ClNO2 production at low bulk phenol concentrations. We interpret measurements of the dependence of the ClNO2 yield on phenol using a kinetic model, where we confine the surface enhancement in phenol to the top 1 nm of the interface. Our results are most consistent with a model where N2O5 is ionized within the first three water monolayers (<1 nm), where the product nitronium ions react rapidly with interfacial phenol molecules. These results suggest that ClNO2 may not be formed at the air-sea interface at the yield expected for NaCl, and that the reactive uptake of N2O5 and the subsequent product yield of ClNO2 may serve as a unique probe for the composition of the interfacial region of the sea surface microlayer.

Preoperative optimization of crohn disease.

Crohn disease is a chronic disease that is treated with aminosalicylates, antibiotics, and immunosuppressant agents. Most patients ultimately require surgical intervention and many will require additional surgery for recurrent disease. Consequently, surgery is generally performed only when medical management fails; however, these patients are often malnourished and immunosuppressed. Preoperative optimization is necessary to minimize morbidity, including intra-abdominal septic complications and anastomotic leaks. In this article, the authors review some considerations to improve the surgical outcome in Crohn disease.

Is the abdominal repair of rectal prolapse safer than perineal repair in the highest risk patients? An NSQIP analysis.

BACKGROUND: Although the perineal approach in the surgical management of rectal prolapse has a higher recurrence, it is the accepted approach for higher-risk patients because of its lower morbidity. OBJECTIVE: The aim of this study was to determine outcomes of abdominal versus perineal approaches to rectal prolapse repair. DESIGN SETTINGS: A retrospective study was performed comparing outcomes of patients undergoing different types of surgical approaches (open abdominal, laparoscopic, perineal) for rectal prolapse. PATIENTS: The American College of Surgeons National Surgical Quality Improvement Participant User Data Files (2008-2009) were queried for patients undergoing adult, elective procedures for rectal prolapse. MAIN OUTCOME MEASURES: Univariate analysis and multivariate logistic regression were performed to look at age, ASA classification, procedure type, and resultant mortality rate. RESULTS: One thousand four hundred sixty-nine patients meeting our criteria were identified. Older patients (age>80) and higher-risk patients (ASA classifications 3 and 4) were significantly associated with the selection of the perineal approach. The overall mortality rate was 0.5%. The mortality rate for all perineal procedures was 0.9% in comparison with 0.13% for all abdominal operations (p = 0.033). The mortality rate for the highest-risk groups (ASA 3 and 4) for perineal procedures was 1.3% in comparison with 0.35% in the abdominal procedure group; the relative risk for mortality was 4 times greater in the perineal procedure group than in the abdominal procedure group. LIMITATIONS: The retrospective design and standardized outcomes measured use administrative-level data and prevent the assessment of procedure-specific outcomes. CONCLUSIONS: Hospital mortality for the surgical repair of rectal prolapse is uncommon. The decision to choose the abdominal approach for the repair of rectal prolapse may not be as prohibitive as previously thought for higher-risk patients. Because of the broad range of functionality within each ASA classification, the operation offered should always be individualized, and patient selection is the most important factor.

Proactive care post-discharge to reduce 30 day readmissions to hospital.

BACKGROUND: Healthwatch England estimated emergency readmissions have risen by 22.8% between 2012-13 and 2016-17. Some emergency readmissions could be avoided by providing patients with urgent out of hospital medical care or support. Sovereign Health Network (SHN) comprises of three GP practices, with a combined population of 38,000. OBJECTIVE: We will decrease the number of SHN patients readmitted within 30 days of discharge from Portsmouth Hospitals Trust following a non-elective admission (excluding Emergency Department attendance) by 40-60% by July 2020. METHODS: Four Plan, Do, Study, Act (PDSA) cycles were used to test the administrative and clinical processes. Our Advanced Nurse Practitioner reviewed all discharge summaries, added alerts to records, and proactively contacted patients either by text, telephone or home visit. RESULTS: 92 patients aged 23 days to 97 years were admitted onto the recent discharge scheme. Half of discharge summaries were received on the day of discharge, whilst 29% of discharge summaries were received more than 24 hours post-discharge, and one was received 11 days post-discharge. Following our interventions, there were 55% less than expected readmissions during the same time period. CONCLUSION: To allow proactive interventions to be instigated in a timely manner, discharge summaries need to be received promptly. The average readmission length of stay following a non-elective admission is seven days. Our proactive interventions saved approximately 102.9 bed days, with potential savings of 1,775 bed days over a year. We feel the results from our model are promising and could be replicated by other Primary Care Networks to result in larger savings in bed days.

[Waiting time for and length of physicianc's consultation define the patient-physician interaction: results of a prospective study in 478 patients with chronic viral hepatitis]. / Wartezeiten und Länge des Arztgesprächs bestimmen aus Patientensicht die Qualität der Arzt-Patienten-Beziehung bei chronischer Hepatitis B und C: Ergebnisse einer prospektiven Studie bei 478 Patienten mit chronischer Virushepatitis.

BACKGROUND: Little is known about the physician-patient interaction in hepatitis B and C. METHODS: This study by the federal competence network hepatitis analysed the physician-patient interaction using the validated FAPI questionnaire. The questionnaire also contained questions concerning demography and disease characteristics. Of the total 1500 questionnaires sent out, 478 were returned (32 %) (20 % HBV vs. 80 % HCV). RESULTS: The FAPI index of patients with HBV/HCV infection (3.10 +/- 0,99) was lower than that in patients with other internal medicine diseases (3.61 +/- 0.92; n = 148). Women had lower values than men (2.98 vs. 3.25; p = 0.005). Patients with active HBV infection showed higher values than those with HCV infection (3.27 vs. 2.97; p < 0.05). Patients with successfully treated hepatitis B/C had higher values than those with active disease (3.36 vs. 3.02; p = 0.004). The index was lower in patients who waited > 2 weeks for the consultation when compared to those with a shorter wait (2.92 vs. 3.31; p < 0.001) and was also lower in patients who waited > 30 min at the consultation day when compared to those with a shorter wait (2.81 vs. 3.39; p < 0.001). The index gradually increased with the consultation length (2.47 < 10 min vs. 2.79 10 - 15 min vs. 3.21 15 - 30 min vs. 3.82 > 30 min; p < 0.001). The index was higher in patients seen by gastroenterologists (3.43) when compared with general practioners (3.10), internists (3.02) and clinical settings (3.13) (p < 0.05). A good information status was associated with higher FAPI values when compared with a bad information status (3.43 vs. 2.76; p < 0.001). Fibrosis, health insurance and age were not associated with FAPI index (p > 0.2). By multivariate analysis a long consultation, a good information status, patients' patience, short waiting times, and providing contact to a patient support group were independently associated with a high index. CONCLUSIONS: The physician-patient interaction in chronic viral hepatitis is worse than in other internal medicine diseases with problems being more pronounced in HCV infection and women when compared to men and HBV infection. Short waiting times and patients' patience ameliorated the interaction as well as the consultation length, the information status of the patient and providing contact to a patient support group. Type of health insurance did not affect either waiting times or physician-patient interaction; thus there is no hint for a two-class medicine in this part of hepatology.

Tunable Anion-Selective Transport through Monolayer Graphene and Hexagonal Boron Nitride.

Membranes that selectively filter for both anions and cations are central to technological applications from clean energy generation to desalination devices. 2D materials have immense potential as these ion-selective membranes due to their thinness, mechanical strength, and tunable surface chemistry; however, currently, only cation-selective membranes have been reported. Here we demonstrate the controllable cation and anion selectivity of both monolayer graphene and hexagonal boron nitride. In particular, we measure the ionic current through membranes grown by chemical vapor deposition containing well-known defects inherent to scalably produced and wet-transferred 2D materials. We observe a striking change from cation selectivity with monovalent ions to anion selectivity by controlling the concentration of multivalent ions and inducing charge inversion on the 2D membrane. Furthermore, we find good agreement between our experimental data and theoretical predictions from the Goldman-Hodgkin-Katz equation and use this model to extract selectivity ratios. These tunable selective membranes conduct up to 500 anions for each cation and thus show potential for osmotic power generation.

Peripartum care of the parturient with acute fatty liver of pregnancy.

Acute fatty liver of pregnancy (AFLP) is a rare, but serious life-threatening clinical entity, the etiology of which is unknown. The clinical presentation of this disease is varied and timely diagnosis often difficult. Since multiorgan involvement (and dysfunction) complicates diagnosis, no uniform peripartum obstetric and anesthetic recommendations can be made. Still, once the diagnosis of AFLP is established, prompt delivery is indicated. We herein present a case of acute fatty liver and hepatic failure that developed during the third trimester of pregnancy. Favorable maternal and fetal outcome was accomplished.

Isolation and preliminary in vitro characterization of the porcine pulmonary intravascular macrophage.

Porcine intravascular macrophages were isolated by perfusion of the pulmonary vasculature with 0.1% collagenase solution. The isolated cells formed intercellular adhesion plaques with endothelial cells when incubated with porcine pulmonary artery, aorta, and corneal cups. Intercellular adhesion plaques were focal junctionlike membrane specializations consisting of paired submembranous amorphous densities subjacent to 15-20 nm gaps between parallel apposing cell membranes. The intermembranous space was filled with moderately electron dense, finely granular material. Adhesion plaques formed in 4-8 hours and resembled the adhesion plaques formed between pulmonary intravascular macrophages and endothelium in vivo. Alveolar macrophages and peripheral blood monocytes did not form intercellular adhesion plaques with endothelial cells. Intravascular macrophages had histologic and ultrastructural features of macrophages, were alpha naphthyl butyrate esterase positive, adhered to plastic coverslips after 1 hour of incubation, and were smaller than alveolar macrophages and endothelial cells. The formation of intercellular adhesion plaques in vivo and in vitro by cells with morphologic and histochemical features of macrophages distinguishes intravascular macrophages from monocytes and alveolar macrophages.

A randomized comparison of a five-minute versus fifteen-minute lockout interval for PCEA during labor.

BACKGROUND: The best combination of bolus size and lockout interval for patient-controlled epidural analgesia (PCEA) is not known. This study compared a 5-min with a 15-min lockout interval. METHODS: Parturients were randomly assigned to receive PCEA with either a 5-min or a 15-min interval. All had a 15-mL loading dose, continuous background infusion 6 mL/h of 0.125% bupivacaine plus fentanyl 2 mug/mL, PCEA bolus volume 5 mL, maximum hourly dose 26 mL. Visual analogue scores for pain, nausea and pruritus, sensory levels to ice, sacral analgesia, motor power, blood pressure and fetal heart rate were assessed pre-epidural and regularly thereafter until delivery. The numbers of boluses and attempts and patient satisfaction were recorded. RESULTS: 29 patients were assigned to the 5-min group and 31 to the 15-min group, but the 15-min group contained twice as many nulliparous women. Side-effect and complication rates did not differ between groups. VAS pain scores were reduced from a median of 79 in the 15-min group and 82 in the 5-min group to a median of zero 30 min after epidural insertion. Bolus/attempt ratio was 0.88 in the 5-min vs. 0.70 in the 15-min group. The numbers of requests for physician intervention were similar. No differences in pain scores, side-effects, drug use or patient satisfaction were demonstrated. CONCLUSION: The 5-min lockout interval appears the more efficient and has been used safely in our practice for 15,000 parturients, although a larger study is required to confirm the relative efficacy, efficiency and safety of this regimen.

Differential activation of microglia and astrocytes following trimethyl tin-induced neurodegeneration.

We have investigated the response of astrocytes and microglia to trimethyl tin intoxication in the septum, hippocampus, olfactory bulb, and pyriform cortex of the rat. Microglia were studied qualitatively using lectin histochemistry, and astrocytes were examined both qualitatively with immunohistochemistry, and quantitatively using an immunoassay for glial fibrillary acidic protein. Our results show that activated microglia first appeared 2 days after trimethyl tin intoxication in the lateral septum and hippocampus. Four days after trimethyl tin intoxication, the same regions revealed a most intense microglial reaction characterized by microglial hypertrophy and the formation of phagocytic clusters. By day 7, microglial activation in the septum and hippocampus had lessened, suggesting that the cells were reverting to the resting phenotype. The microglial response in the pyriform cortex and olfactory bulb, while being later in onset than in the septum and hippocampus, showed a similar progression of microglial changes reaching maximal intensity 7 days after trimethyl tin intoxication. Significant increases in the expression of glial fibrillary acidic protein were observed in all regions examined and typically occurred after microglial activation was already underway. We conclude that microglial and astroglial reactions which occur in response to trimethyl tin-induced neuronal necrosis are separated in time, with microglial activation preceding astrogliosis. In addition, our study stresses the importance of microglia as an endogenous source of CNS macrophages, and illustrates the merit of histochemical analysis with microglial markers for the early delineation of neurotoxicant-induced brain damage.

Pathogenicity of equine herpesvirus 1 subtype 2 for foals and adult pony mares.

Three pony mares and 4 pony foals were inoculated with a subtype 2 strain of equine herpesvirus 1. Foals had periods of fever 12 h and 2.5 days after inoculation and leukopenia, involving both neutrophils and lymphocytes, followed by leukocytosis. Mares had transient fever and leukopenia 24 hours after inoculation that were less severe than in foals. An increase in circulating virus-neutralizing antibody was seen in 2 of 3 inoculated mares, but not in foals. Attempts to isolate virus from blood were unsuccessful. These studies show that equine herpesvirus 1 subtype 2 is a mild pathogen for ponies and infection may result in inapparent clinical disease.

A 91-day feeding study in rats with caprenin.

Caprenin, a randomized triglyceride primarily comprising caprylic (C8:0), capric (C10:0), and behenic (C22:0) acids, was administered in a semi-purified diet to weanling Sprague-Dawley rats (25/sex/group) at dose levels of 5.23, 10.23 or 15.00% (w/w) for 91 days. Corn oil was added at 8.96, 5.91 and 3.00%, respectively, to provide essential fatty acids and digestible fat calories. Corn oil alone (12.14%) and a blend of medium-chain triglyceride (MCT) oil plus corn oil (11.21 and 3.13%, respectively) served as controls. All diets were formulated to provide about 4000 kcal/kg of diet and 26.8% of digestible calories from fat by assuming that corn oil, MCT oil, and caprenin provided 9, 7 and 5 kcal/g, respectively. Survival, clinical signs, body weight, feed consumption, feed efficiency, organ weights, organ-to-body-weight ratios, organ-to-brain-weight ratios, haematological values and clinical chemistry parameters were evaluated in all groups. Histopathology of a full complement of tissues was evaluated in the corn oil and MCT oil control groups as well as the high-dose caprenin group. Additional rats (n = 5/sex/group) were included in the study to determine whether there was marked storage of C22:0 in heart, liver or perirenal fat at the end of the 91-day feeding period. No significant differences in body weight gain were measured with the balanced caloric diets, although feed conversion efficiency was reduced in the high-dose caprenin group. No adverse effects from the ingestion of caprenin were detected, nor were significant amounts of C22:0 present in the fat extracted from the selected fat depot sites. These results establish a no-observable-adverse-effect level (NOAEL) of more than 15% (w/w) caprenin in the diet (or more than 83% of total dietary fat), which is equal to a mean exposure level of more than 13.2 g/kg/day for male rats and more than 14.6 g/kg/day for female rats.

Actinobacillus pleuropneumoniae: molecular aspects of virulence and pulmonary injury.

Contributions made by several laboratories in the area of Actinobacillus pleuropneumoniae virulence and its relationship to pulmonary disease will be reviewed briefly. Lung injury and subsequent disease, after infection with A. pleuropneumoniae, can be related to various bacterial toxins and host factors. Similar to other gram-negative bacteria. A. pleuropneumoniae has cell wall lipopolysaccharides which have been incriminated in a wide variety of toxic and tissue damaging processes. Virulent isolates of A. pleuropneumoniae have been shown to have a thick capsule whereas some avirulent isolates have a thin and easily removed capsule. The capsule of A. pleuropneumoniae is a linear unbranched polysaccharide composed of repeating dissaccharide subunits that bestow antiphagocytic properties to the bacterium but are also immunogenic. In addition, A. pleuropneumoniae has several chemically defined exotoxins. These toxins have generally been shown to be proteinaceous molecules that are hemolytic, cytotoxic, or edemogenic. Some of these toxins are proteolytic and others have the putative activity of being lytic for secretory IgA. Several of these molecules are capable of inducing lesions that are similar to those observed in natural infections and disease. Endogenous host factors have also been implicated in the development of lung lesions after infection by A. pleuropneumoniae Coagulation and inflammatory pathways have been demonstrated to be pivotal in the early phases of lesion development. In addition, the immune status of the animal is clearly related to the severity and ultimate outcome of A. pleuropneumoniae infection. To adequately treat and prevent this disease, we must understand the distinguishable interactions that occur between the host and the various molecular virulence attributes of A. pleuropneumoniae.

Responses of equine neutrophils to contagious equine metritis organism and its lipopolysaccharides.

Morphology and function of equine neutrophils were evaluated after combination with contagious equine metritis organism (CEMO) or 1 of 2 CEMO lipopolysaccharides (LPS). The 2 LPS (LPS-a; LPS-p) isolated from the CEMO contained 14- and 16-carbon fatty acids, ketodeoxyoctanate, hexose, and heptose, but were morphologically distinct. Neutrophils exposed to LPS had fewer granules, whereas those exposed to CEMO had more granules than did the controls (phosphate-buffered saline solution). Neutrophil iodination was significantly increased with 10 and 25 micrograms of LPS-a, but not significantly altered by LPS-p or CEMO. Staphylococcus aureus ingestion was not influenced by CEMO and was mildly decreased by LPS-a. These results indicate that CEMO may have at least 2 functionally and morphologically distinct, but chemically similar, LPS and that 1 of these LPS (LPS-a) may enhance neutrophil killing by stimulating neutrophil iodinating mechanisms.

Functional and ultrastructural changes in neutrophils from mares and foals experimentally inoculated with a respiratory tract strain of equine herpesvirus-1.

Neutrophils isolated from venous blood of adult and foal ponies inoculated with equine herpesvirus-1 were evaluated by in vitro function tests and by electron microscopy. Foals had fever and severe neutropenia 24 hours after inoculation; increased neutrophil random migration under agarose and decreased antibody-dependent cell-mediated cytotoxicity were significant at 24 hours, but values had returned to preinoculation levels by 72 hours. Mares had fever and leukopenia of less severity, increases in neutrophil migration, and longer persistence of primary granule release than were seen in foals. Reduced migration and degranulation, and a decrease in antibody-dependent cell-mediated cytotoxicity seen with neutrophils from foals, as compared with mares, may relate to the high susceptibility of foals to equine herpesvirus-1 infection.

Phagocytosis and intracellular killing of the contagious equine metritis organism by equine neutrophils in genital secretions.

Equine neutrophils were combined with contagious equine metritis organism (CEMO) or Escherichia coli in vitro in the presence of seminal plasma, uterine flushings, or Hank's balanced salt solution (HBSS). Phagocytosis and intracellular killing were estimated by bacterial culture and light and electron microscopy. With lysed neutrophils, the numbers of colony-forming units of CEMO and E coli increased in seminal plasma and uterine flushings. Numbers of CEMO decreased in HBSS. The numbers of CEMO increased more in the presence of seminal plasma than the other media. When neutrophils were in the various media, 29% to 32% of the CEMO were phagocytized by 120 minutes. At all sampling times and in all media types, more E coli than CEMO were observed to be associated with neutrophils. By 210 minutes' incubation in uterine flushings, seminal plasma, and HBSS, 60% to 75% of the intracellular CEMO were killed. Of the intracellular E coli in the various media, 85% to 90% were killed by 210 minutes. Seemingly, CEMO is an extracellular pathogenic bacteria and immunoglobulins in seminal plasma and uterine flushings from horses not previously infected with CEMO do not enhance CEMO phagocytosis or intracellular killing.

Functional and ultrastructural evaluation of neutrophils from foals and lactating and nonlactating mares.

Neutrophils from 4 pony foals, 3 lactating pony mares, and 3 nonlactating mares were evaluated ultrastructurally and by in vitro function tests. Neutrophils from foals had significantly (P = 0.05) less random migration than neutrophils from mares; values in tests for iodination and Staphylococcus aureus ingestion were also lower with foal neutrophils. Neutrophils from lactating mares had lower responses to iodination, antibody-dependent cell-mediated cytotoxicity, and random migration tests than did neutrophils from nonlactating mares. Ultrastructurally, granule concentration did not differ significantly among groups. A slight decrease in primary granules and a corresponding increase in granules with a flocculent matrix indicates partial spontaneous neutrophil degranulation in foals and lactating mares.

Relationship between gastric inflammatory response and symptoms in patients infected with Helicobacter pylori.

The relationship between the histologic severity of gastritis and associated symptoms was examined in 19 adult patients infected with Helicobacter pylori. At the time of gastrointestinal endoscopy, symptoms of dyspepsia were assessed by means of a linear analog scale. Gastric inflammation was quantitated with histomorphometric techniques. Symptoms such as epigastric pain, burping/belching, and nausea correlated with the degree of inflammation. These positive correlations suggest that the severity of the histologic gastritis contributes to the severity of symptoms. Therefore, utilization of a linear analog scale to assess symptoms may be a useful technique in evaluating the outcome of therapeutic trials of patients with symptomatic H. pylori infection.

Gastritis associated with infection by Helicobacter pylori in humans: geographical differences.

Previous studies have indicated that infection rates of Helicobacter pylori are influenced by geographical factors. The present studies evaluate the characteristics of gastritis, associated with infection by H. pyrlori, and demonstrate relationships between different geographical locations and the extent of inflammatory cell accumulation in the gastric mucosa. Gastric biopsy specimens were obtained from patients infected with H. pylori at three clinical sites (two from North America and one from South America). Gastric inflammation was evaluated by quantitative histomorphometric techniques. Patients from South America had a more severe gastritis than did those from North America. Additionally, in South American patients the neutrophil was the predominant inflammatory cell type in the gastric mucosa. In contrast, the lymphocyte was the primary cell composing the mucosal infiltrate of infected North American subjects. Eosinophil infiltration into the mucosa correlated with the extent of mucosal atrophy; however, there were no differences between the North and South American patient populations in the extent of mucosal atrophy present in the specimens. We conclude that the characteristics (severity and cell type) of gastritis associated with infection by H. pylori are influenced by geographical factors that may be similar to those that modify infection rates for different geographical locations.