Folding pathways to crumpling in thermalized elastic frames

The mechanical properties of thermally excited two-dimensional crystalline membranes can depend dramatically on their geometry and topology. A particularly relevant example is the effect on the crumpling transition of holes in the membrane. Here we use molecular dynamics simulations to study the case of elastic frames (sheets with a single large hole in the center) and find that the system approaches the crumpled phase through a sequence of origami-like folds at decreasing length scales when temperature is increased. We use normal-normal correlation functions to quantify the temperature-dependent number of folds.

Characterization of adult obesity in Florida using the OneFlorida clinical research consortium

INTRODUCTION

With obesity rates and obesity-related healthcare costs increasing, policy makers must understand the scope of obesity across populations.

OBJECTIVE

This study sought to characterize adult obesity using electronic health records (EHRs) available from a statewide clinical data research network, the OneFlorida Clinical Research Consortium, which contains claims and EHR data from over 12 million patients in Florida. The primary aim was to compare EHR-based Florida obesity rates with those rates obtained from the Behavioural Risk Factor Surveillance System (BRFSS).

METHODS

Body mass index from OneFlorida patient data (2012-2016) was used to characterize obesity among adults 20-79 years old. Obesity rates from both OneFlorida and BRFSS (2013) were reported by demographics and by county.

RESULTS

Among the 1,344,015 adults in OneFlorida with EHR data and who met inclusion criteria, the obesity rate was 37.1%. Women had higher obesity rates compared with men. Obesity rates varied within racial/ethnic groups, with the highest rate among African-Americans (45.7%). Obesity rates from OneFlorida were consistently higher than those found in BRFSS (overall 27.8%).

CONCLUSIONS

Utilizing clinical big data available through hospital system and health partner collaborations provides an important view of the extent of obesity. Although these data are available only from healthcare users, they are large in scope, directly measured and are available sooner than commonly used national data sources.

A clarification for the subgenera of Paramacrobiotus Guidetti, Schill, Bertolani, Dandekar and Wolf, 2009, with respect to the International Code of Zoological Nomenclature

The recent re-description of Paramacrobiotus Guidetti, Schill, Bertolani, Dandekar and Wolf, 2009 has inadvertently led to the description of an objective synonym within its subgenera nominal taxa. To resolve this issue, we have re-described both subgenera, and proposed a new substitute name for one subgenus, in line with the International Code of Zoological Nomenclature. Additionally we have confirmed the placement of two recently published Paramacrobiotus species, not included in the last revision, within the respective subgenera established herein.

All-oral direct-acting antiviral therapy in HCV-advanced liver disease is effective in real-world practice: observations through HCV-TARGET database

BACKGROUND

Chronic hepatitis C virus therapy in patients with advanced liver disease remains a clinical challenge. HCV-TARGET collects data in patients treated at tertiary academic and community centres.

AIM

To assess efficacy of all-oral HCV therapy in advanced liver disease.

METHODS

Between December 2013 and October 2014, 240 patients with a MELD score of ≥10 initiated HCV treatment with an all-oral regimen. Data from the 220 patients who completed 12-week follow-up were analysed.

RESULTS

Genotype 1 (GT1) patients had higher sustained virological response (SVR) when treated with sofosbuvir plus simeprevir ± ribavirin than with sofosbuvir plus ribavirin (66-74% vs. 54%); GT1b vs GT1a (84% vs. 64%). SVR for GT2 was 72% with sofosbuvir plus ribavirin, while GT3 patients had a substantially lower response (35%). A decrease in MELD score was not clearly related to SVR over the short course of follow-up although some had improvements in MELD score, serum bilirubin and albumin. A predictor of virological response was albumin level while negative predictors were elevated bilirubin level and GT1a. Most patients with GT1 were treated with approximately 12-week duration of sofosbuvir and simeprevir ± ribavirin therapy while GT2 and GT3 patients were treated with approximately 12 and 24 weeks of sofosbuvir plus ribavirin respectively.

CONCLUSIONS

All-oral therapies are effective among patients with advanced liver disease with high levels of success in GT2 and GT1b, and may serve to reduce the severity of liver disease after SVR. Treatment for GT3 patients remains an unmet need. Clinical trial number: NCT01474811.

Obesity and glycemic control in patients with diabetes mellitus: Analysis of physician electronic health records in the US from 2009-2011

AIMS

Examine the association between obesity and glycemic control among patients with type 1 (T1DM) or type 2 diabetes mellitus (T2DM).

METHODS

Data from US physician electronic health records (Humedica®) from 2009-2011 were utilized. Patients were defined as having above-target glycemic control if they had an HbA1c ≥7% at any time during the study period. Multinomial logistic regressions were conducted separately for T1DM and T2DM patients, and examined associations between BMI categories and probability of having above-target glycemic control (≥7% and <8%, ≥8% and <9%, or ≥9%) while controlling for patient demographics, general health, comorbid conditions, and antihyperglycemic medication use.

RESULTS

There were 14,028 T1DM and 248,567 T2DM patients; 47.8% of T1DM and 63.4% of T2DM were obese (BMI ≥30kg/m(2)). For T1DM, being overweight (BMI 25-<30), obese class I (30-<35), II (35-<40), or III (≥40) was associated with a significantly higher probability of having HbA1c≥8% and <9% or ≥9%, while being overweight was associated with a significantly higher probability of having HbA1c ≥7% and <8% compared to normal BMI (BMI≥18.5 and<25). For T2DM patients, being overweight, obese class I, II, or III was associated with a significantly higher probability of having HbA1c ≥7% and <8%, ≥8% and <9%, or ≥9%.

CONCLUSIONS

For both T1DM and T2DM patients, there were positive and statistically significant associations between being overweight or obese and having suboptimal glycemic control. These findings quantify the associations between obesity and glycemic control, and highlight the potential importance of individual characteristics on glycemic control.

Effectiveness of Simeprevir Plus Sofosbuvir, With or Without Ribavirin, in Real-World Patients With HCV Genotype 1 Infection

BACKGROUND & AIMS

The interferon-free regimen of simeprevir plus sofosbuvir was recommended by professional guidelines for certain patients with hepatitis C virus (HCV) genotype 1 infection based on the findings of a phase 2 trial. We aimed to evaluate the safety and efficacy of this regimen in clinical practice settings in North America.

METHODS

We collected demographic, clinical, and virologic data, as well as reports of adverse outcomes, from sequential participants in HCV-TARGET--a prospective observational cohort study of patients undergoing HCV treatment in routine clinical care settings. From January through October 2014, there were 836 patients with HCV genotype 1 infection who began 12 weeks of treatment with simeprevir plus sofosbuvir (treatment duration of up to 16 weeks); 169 of these patients received ribavirin. Most patients were male (61%), Caucasian (76%), or black (13%); 59% had cirrhosis. Most patients had failed prior treatment with peginterferon and ribavirin without (46%) or with telaprevir or boceprevir (12%). The primary outcome was sustained virologic response (SVR), defined as the level of HCV RNA below quantification at least 64 days after the end of treatment (beginning of week 12 after treatment--a 2-week window). Logistic regression models with inverse probability weights were constructed to adjust for baseline covariates and potential selection bias.

RESULTS

The overall SVR rate was 84% (675 of 802 patients, 95% confidence interval, 81%-87%). Model-adjusted estimates indicate patients with cirrhosis, prior decompensation, and previous protease inhibitor treatments were less likely to achieve an SVR. The addition of ribavirin had no detectable effects on SVR. The most common adverse events were fatigue, headache, nausea, rash, and insomnia. Serious adverse events and treatment discontinuation occurred in only 5% and 3% of participants, respectively.

CONCLUSIONS

In a large prospective observational cohort study, a 12-week regimen of simeprevir plus sofosbuvir was associated with high rates of SVR and infrequent treatment discontinuation. ClinicalTrials.gov: NCT01474811.

Tibial bone versican content decreases with zoledronate treatment in adult mice

In bone remodeling, the expression and turnover of the proteoglycans versican and aggrecan are poorly understood. We report changes in adult mouse bone contents of versican and aggrecan associated with both age and treatment with the drug zoledronate. The data may have implications for experimental animal models of osteoporosis and related conditions.

INTRODUCTION

Versican and aggrecan are large, aggregating proteoglycans involved in skeletal development, but little is known about their roles in bone remodeling. The purpose of this study was to investigate versican and aggrecan contents in adult mouse bones, and changes in their contents in response to the bisphosphonate zoledronate (ZOL).

METHODS

Mice (9 weeks old) were treated with 125 μg/kg ZOL or vehicle for 3 or 15 weeks. Versican and aggrecan were isolated from tibial bones for Western blotting, automated integrated densitometry, and analysis (two-way ANOVA, α = 0.05).

RESULTS

In ZOL-treated mouse bones, compared to vehicle, 340 and 60 kDa versican content decreased significantly, and 100 and 60 kDa aggrecan content decreased significantly (drug effect). In 24-week-old mouse bones, compared to 12 weeks, statistically significant decreases were observed in 340, 80, 60, and 11 kDa versican, and in 100, 70, and 40 kDa aggrecan (age effect). There was a statistically significant ZOL-age interaction for 330 kDa aggrecan.

CONCLUSION

This is the first study to assess physiological versican and aggrecan adaptations in adult mammalian bone tissue, in the presence and absence of ZOL. We observed large decreases in some versican and aggrecan species from 12 to 24 weeks. We also observed decreases in several versican and aggrecan species in the presence of ZOL. This indicates that bone proteoglycan expression and turnover may be important in bone remodeling.

Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines for IFNL3 (IL28B) genotype and PEG interferon-α-based regimens

Pegylated interferon-α (PEG-IFN-α or PEG-IFN 2a and 2b)- and ribavirin (RBV)-based regimens are the mainstay for treatment of hepatitis C virus (HCV) genotype 1. IFNL3 (IL28B) genotype is the strongest baseline predictor of response to PEG-IFN-α and RBV therapy in previously untreated patients and can be used by patients and clinicians as part of the shared decision-making process for initiating treatment for HCV infection. We provide information regarding the clinical use of PEG-IFN-α- and RBV-containing regimens based on IFNL3 genotype.

Contact sex pheromone in the tsetse flyGlossina pallidipes (Austen) Identification and Synthesis

Adult maleG. pallidipes attempted to copulate with decoys treated with a branched paraffin obtained from laboratory-reared female flies. The compound causing maximal response was isolated and identified as 13,23-dimethylpentatriacontane. The synthesized compound elicited increasing responses with increasing doses. This sex- and species-specific compound was always present in physiological amounts in females, as it increased from 2 μg at emergence to 10 μg per female at 14 days. It was present in wild-caught females from a wide geographical range.

The anti-viral effect of sorafenib in hepatitis C-related hepatocellular carcinoma

BACKGROUND

Sorafenib is currently the only approved systemic therapy shown to have efficacy in the treatment of advanced hepatocellular carcinoma (HCC). Recent studies suggest that hepatitis C (HCV)-related HCC patients derive more clinical benefit from sorafenib than other subgroups, but the mechanism for this effect is unknown. In vitro data suggest that sorafenib may exert anti-viral properties, and thus our aim in this study was to evaluate potential anti-viral activity of sorafenib in patients with HCV-related HCC.

AIM

To evaluate potential anti-viral activity of sorafenib in patients with HCV-related HCC.

METHODS

We prospectively enrolled patients with HCV-related HCC treated with sorafenib for up to 6 months. Baseline clinical, viral and oncologic data were collected. Patients' HCV viral loads were obtained at various time points, and compared with their baseline viral levels. No patients received any known anti-viral therapy during this time.

RESULTS

Thirty-three patients were identified with baseline and subsequent HCV levels available for analysis. Six patients completed 6 months of full dose sorafenib, and comparisons of their HCV viral loads showed no significant change at week 24 (difference of means = 0.3500, CI: -0.1799-0.8799, P = 0.150), or the interim time points. Similarly, the HCV viral loads of all patients who received sorafenib and the viral loads of those patients who had tumour response to sorafenib showed no significant changes at any time point.

CONCLUSION

Despite preclinical data and previous subgroup analyses suggesting that sorafenib has an anti-viral effect against HCV, this study suggests that sorafenib lacks significant anti-viral activity in HCV patients with HCC.

The combination of sorafenib with transarterial chemoembolisation for hepatocellular carcinoma

BACKGROUND

Standard of practice involves using transarterial therapy for multifocal hepatocellular carcinoma (HCC) alone and sorafenib only for more advanced HCC, but the sorafenib and transarterial therapy combination may provide greater efficacy.

AIM

To evaluate the safety and efficacy of concurrent sorafenib and transarterial therapy in HCC.

METHODS

Consecutive cases of HCC were treated with sorafenib and transarterial therapy, receiving sorafenib 2 to 4weeks before transarterial therapy. Baseline clinical parameters, adverse events (AEs) and survival were collected.

RESULTS

A total of 47 patients received sorafenib and transarterial therapy. The majority of the patients were male (70%) with HCV (60%), median age of 60years, good performance status (0-1), stable cirrhosis (Child: A 72%; B 28%), unresectable tumour (stage: B 81%; C 19%) and median AFP of 24ng/mL. Median follow-up was 12months and median time on sorafenib was 6months. LC Bead TACE was used with a median frequency of 3. The majority of the patients (89%) experienced AEs. The most common AEs were fatigue (51%), hand-foot skin reaction (51%) and diarrhoea (43%). Grade 3 and 4 AEs included fatigue (13%) and hand-foot skin reaction (26%). Most patients required a dose reduction (66%). The main AE related to transarterial therapy was post-TACE syndrome (23%). The disease control rate was 68% at 6months. Overall median survival rate was 18.5months (95% CI 16.1-20.9months).

CONCLUSION

Concurrent sorafenib and transarterial therapy is overall safe with no unexpected side effects and encouraging efficacy that warrants further study.

Pilot study: fenofibrate for patients with primary biliary cirrhosis and an incomplete response to ursodeoxycholic acid

BACKGROUND

Newer therapies are needed for patients with primary biliary cirrhosis and incomplete response to ursodeoxycholic acid (UDCA). Fenofibrate is a fibric acid postulated to regulate immune response and cell proliferation.

AIM

To evaluate the efficacy and safety of fenofibrate in patients with primary biliary cirrhosis and incomplete response to UDCA.

METHODS

We undertook a pilot study involving 20 patients with primary biliary cirrhosis and serum alkaline phosphatase (ALP) ≥ 2× ULN. Nonparametric statistical tests and Spearman correlation test were used as appropriate.

RESULTS

Twenty patients received fenofibrate (160 mg/day) in addition to UDCA for 48 weeks. Median serum ALP decreased significantly at 48 weeks compared with baseline values [351 (214-779) U/L at baseline vs. 177 (60-384) U/L at 48 weeks, P < 0.05]. A rebound in ALP occurred upon drug discontinuation. Serum aspartate aminotransferase and Immunoglobulin M also decreased significantly, while bilirubin and albumin remained unchanged. Median IL-1 decreased from 28.9 (2.7-10 000) to 11.3 (2.5-277.7) pg/mL (P = 0.049), and median IL-6 from 4.6 (3.2-5205) to 3.5 (3.2-73.4) pg/mL (P = 0.027). Heartburn was the most frequent adverse event, leading to discontinuation of two study subjects.

CONCLUSIONS

Combination therapy of fenofibrate and UDCA induced significant biochemical improvement in patients with primary biliary cirrhosis and incomplete response to UDCA. Further studies are warranted.

Influence of serum and soluble CD25 (sCD25) on regulatory and effector T-cell function in hepatocellular carcinoma

Our previous studies showed that high levels of soluble CD25 (sCD25) in the serum of patients with hepatocellular carcinoma (HCC) correlated with blunted effector T-cells (Teff) responses, tumour burden and poor survival. Understanding the interactions between Teff, CD4+CD25+ regulatory T cells (Treg) and soluble factors can identify novel therapeutic targets. In this study, we characterize the mechanisms by which HCC serum and sCD25 mediate suppression of Teff and evaluate the effect of sCD25 on the suppression assays with normal healthy control cells (NHC) at a 1:1 Treg to Teff cell ratio to determine whether sCD25 has any impact on Treg suppression. HCC serum and sCD25 suppressed Teff proliferation and downregulated CD25 expression on HCC Teff in a dose-dependent fashion with sCD25 doses above 3000 pg/ml. Treg from HCC and cirrhosis patients suppressed proliferation of target CD4+CD25- Teff in serum-free medium (SFM). HCC Treg showed a higher degree of suppression than cirrhosis-derived Treg. In contrast, Treg from NHC did not suppress target Teff in SFM. However, isolated Treg from all three study subjects (HCC, cirrhosis and NHC) suppressed CD4+CD25- Teff in serum conditions or in the presence of sCD25 in the range 6000-12,000 pg/ml. In conclusion, downregulation of CD25 cell surface expression on Teff is part of the overall suppressive mechanism of sCD25 and HCC serum on Teff responses. The observed sCD25 and HCC serum-mediated suppression is further influenced via novel immune-inhibitory interaction between CD4+CD25+ Treg and sCD25.

Transfusion has no effect on recurrence in hepatitis C after liver transplantation

BACKGROUND

The literature suggests that blood product transfusions have a negative impact on the survival of liver transplant patients. We investigated the impact of intraoperative blood product usage on the survival of liver transplantation patients being transplanted for hepatitis C-related end-stage liver disease. In addition, we analyzed a potentially more sensitive metric, namely disease recurrence and fibrosis progression, obtained from follow-up liver biopsies.

METHODS

We retrospectively studied 194 consecutive patients with hepatitis C virus (HCV) undergoing liver transplantation. To investigate the effect of red blood cell (RBC) or platelet transfusions on post-transplant HCV recurrence, hepatic biopsy data from 4 months and 1 year after transplantation were studied. In addition, survival data were analyzed.

RESULTS

There was no effect of intraoperative RBC or platelet transfusion on either 1- or 5-year patient survival following liver transplantation. There was no difference in HCV disease recurrence or progression of hepatic fibrosis at 4 months or 1 year attributable either to RBC or to platelet transfusion.

CONCLUSION

This study was not able to confirm an effect on the survival of HCV-infected liver transplant patients related to intraoperative transfusion of RBCs or platelets. In addition, these transfusions had no effect on HCV recurrence or fibrosis progression. This is not to condone a liberal transfusion practice, but rather to reassure that when clinically indicated, transfusion does not have a significant impact on patient survival or disease recurrence in HCV-infected liver transplant patients.

Novel betapapillomavirus associated with hand and foot papillomas in a cynomolgus macaque

Betapapillomavirus is a genus of papillomaviruses (PVs) commonly found in human skin and associated with both benign and malignant skin lesions. Only 2 previous beta-PVs have been fully characterized in nonhuman species. This report describes a novel beta-PV, named Macaca fascicularis PV type 2 (MfPV2), isolated from exophytic skin papillomas on the hands and feet of a 2-year-old male cynomolgus monkey (M. fascicularis). On histology the papillomas were composed of diffusely thickened epidermis with superficial foci of cytomegaly, cytoplasmic pallor, marginalized chromatin, and rare eosinophilic intranuclear inclusion bodies. Positive immunostaining for p16 and the proliferation marker Ki67 was present multifocally within affected epidermis, most prominently within basal-type cells. Complete sequence identity (100%) was noted between PV genomes fully sequenced from hand and foot lesions. The MfPV2 genome was 7632 base pairs in length and included putative open reading frames (ORFs) for E1, E2, E4, E6, E7, L1, and L2 genes, similar to other PVs. The closest relatives to MfPV2 based on the L1 ORF sequence were all beta-PVs. These included human PV (HPV) 9, HPV115, HPV76, HPV75, and MfPV1 (60-70% pairwise identity for all), the latter of which was also isolated from hand and foot papillomas in a cynomolgus macaque. Phylogenetic analysis placed MfPV2 in a new species group (beta-6), distinct from HPVs (beta-1 to beta-5) and MfPV1 (beta-1). These findings characterize a new nonhuman beta-PV and provide additional support for the idea that tissue tropism among ancestral primate PVs developed prior to divergence of certain Old World primate lineages.

One-year change in radiographic joint space width in patients with unilateral joint space narrowing: data from the Osteoarthritis Initiative

OBJECTIVE

To examine the rate of joint space width (JSW) loss in both knees of patients with unilateral medial joint space narrowing (JSN) at baseline.

METHODS

Cases were selected from a pool of 2,678 subjects enrolled in the Osteoarthritis Initiative cohort. Inclusion criteria for the present study were unilateral medial JSN, bilateral frequent knee pain, and body mass index (BMI) > or = 25 kg/m(2). Baseline and 1-year fixed flexion radiographs of both knees were read (blinded to time point) using an automated algorithm for minimum JSW and JSW at 4 fixed locations in the medial compartment.

RESULTS

Sixty-seven participants met the inclusion criteria: 43 women and 24 men, with mean +/- SD age 60 +/- 9 years and mean +/- SD BMI 31 +/- 4 kg/m(2). Thirty-seven subjects (55%) had > or = 1 definite tibiofemoral osteophyte. The average progression in no-JSN knees was comparable with that in JSN knees (approximately -0.2 mm/year). However, JSW change was more variable in no-JSN knees, resulting in standardized response means (SRMs; the mean/SD) of approximately -0.24 in no-JSN knees versus approximately -0.41 in JSN knees on average at the 4 fixed locations, and SRMs of -0.24 and -0.35, respectively, for minimum JSW. Young age and high BMI were associated with increased progression, especially in JSN knees.

CONCLUSION

JSN and no-JSN knees progressed at a comparable rate, but a wider distribution of JSW change in no-JSN knees resulted in a poorer sensitivity to change in these knees.

Growth of Vibrio anguillarum in Salmon Intestinal Mucus

The physiological changes of Vibrio anguillarum in response to growth in salmon intestinal mucus were investigated. Growth, survival, and changes in protein expression during growth in media supplemented with mucus were compared to growth and starvation in the identical media without mucus. V. anguillarum exhibited a rapid decline in CFU following growth in mucus as the sole carbon source. No such decline was observed in Luria broth with a 2% NaCl concentration, in glucose-minimal broth (3M), or during starvation in a carbon-, nitrogen-, and phosphorus-free salt solution (NSS). The changes in protein expression during growth in mucus were examined by labeling cells with [(sup35)S]methionine and analyzing the labeled proteins by one- and two-dimensional gel electrophoresis and autoradiography. Comparison of [(sup35)S]methionine-labeled proteins from mucus-grown cells with 3M-grown cells and NSS-starved cells revealed four de novo mucus-inducible proteins (Mips). These Mips were localized in the membrane fraction of V. anguillarum. Additionally, at least one other membrane protein was found to have increased expression in response to growth in mucus.

Magnitude and regional distribution of cartilage loss associated with grades of joint space narrowing in radiographic osteoarthritis--data from the Osteoarthritis Initiative (OAI)

OBJECTIVE

Clinically, radiographic joint space narrowing (JSN) is regarded a surrogate of cartilage loss in osteoarthritis (OA). Using magnetic resonance imaging (MRI), we explored the magnitude and regional distribution of differences in cartilage thickness and subchondral bone area associated with specific Osteoarthritis Research Society International (OARSI) JSN grades.

METHOD

Seventy-three participants with unilateral medial JSN were selected from the first half (2678 cases) of the OA Initiative cohort (45, 21, and 7 with OARSI JSN grades 1, 2, and 3, respectively, no medial JSN in the contra-lateral knee). Bilateral sagittal baseline DESSwe MRIs were segmented by experienced operators. Intra-person between-knee differences in cartilage thickness and subchondral bone areas were determined in medial femorotibial subregions.

RESULTS

Knees with medial OARSI JSN grades 1, 2, and 3 displayed a 190 microm (5.2%), 630 microm (18%), and 1560 microm (44%) smaller cartilage thickness in weight-bearing medial femorotibial compartments compared to knees without JSN, respectively. The weight-bearing femoral condyle displayed relatively greater differences than the posterior femoral condyle or the medial tibia (MT). The central subregion within the weight-bearing medial femur (cMF) of the femoral condyle (30-75 degrees ), and the external and central subregions within the tibia displayed relatively greater JSN-associated differences compared to other medial femorotibial subregions. Knees with higher JSN grades also displayed larger than contra-lateral femorotibial subchondral bone areas.

CONCLUSIONS

This study provides quantitative estimates of JSN-related cartilage loss, with the central part of the weight-bearing femoral condyle being most strongly affected. Knees with higher JSN grades displayed larger subchondral bone areas, suggesting that an increase in subchondral bone area occurs in advanced OA.

Review article: the management of hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma is the leading cause of death in cirrhosis. A majority of patients present at an advanced stage with poor prognosis.

AIM

To review the current screening, diagnosis and management strategies involved in hepatocellular carcinoma.

METHODS

A literature search was performed using PubMed for publications with a predetermined search string to identify relevant studies.

RESULTS

Hepatocellular carcinoma is dramatically increasing in incidence that is mostly attributed to chronic hepatitis C and non-alcoholic fatty liver disease/non-alcoholic steatohepatitis and its clinical phenotype diabetes and obesity. Cirrhosis is the major predisposing risk factor and its presence necessitates close surveillance for hepatocellular carcinoma with serial imaging studies. Hepatocellular carcinoma can be diagnosed by its unique radiological behaviour of arterial enhancement and washout on delayed images. The Barcelona Clinic Liver Cancer staging classification system is a clinically useful algorithm for the management of patients with hepatocellular carcinoma. The simultaneous presence of cirrhosis in the patients complicates their management and monitoring for cirrhosis-related complications is important.

CONCLUSIONS

Early diagnosis and definitive treatment remains the key to long-term outcome. A multidisciplinary approach is critical to the successful management of hepatocellular carcinoma. Studies combining sorafenib with locoregional or other targeted molecular therapies are likely to improve responses and outcome.

Review article: the management of hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma is the leading cause of death in cirrhosis. A majority of patients present at an advanced stage with poor prognosis.

AIM

To review the current screening, diagnosis and management strategies involved in hepatocellular carcinoma.

METHODS

A literature search was performed using PubMed for publications with a predetermined search string to identify relevant studies.

RESULTS

Hepatocellular carcinoma is dramatically increasing in incidence that is mostly attributed to chronic hepatitis C and non-alcoholic fatty liver disease/non-alcoholic steatohepatitis and its clinical phenotype diabetes and obesity. Cirrhosis is the major predisposing risk factor and its presence necessitates close surveillance for hepatocellular carcinoma with serial imaging studies. Hepatocellular carcinoma can be diagnosed by its unique radiological behaviour of arterial enhancement and washout on delayed images. The Barcelona Clinic Liver Cancer staging classification system is a clinically useful algorithm for the management of patients with hepatocellular carcinoma. The simultaneous presence of cirrhosis in the patients complicates their management and monitoring for cirrhosis-related complications is important.

CONCLUSIONS

Early diagnosis and definitive treatment remains the key to long-term outcome. A multidisciplinary approach is critical to the successful management of hepatocellular carcinoma. Studies combining sorafenib with locoregional or other targeted molecular therapies are likely to improve responses and outcome.

Pyrosequencing the Manduca sexta larval midgut transcriptome: messages for digestion, detoxification and defence

The tobacco hornworm Manduca sexta is an important model for insect physiology but genomic and transcriptomic data are currently lacking. Following a recent pyrosequencing study generating immune related expressed sequence tags (ESTs), here we use this new technology to define the M. sexta larval midgut transcriptome. We generated over 387,000 midgut ESTs, using a combination of Sanger and 454 sequencing, and classified predicted proteins into those involved in digestion, detoxification and immunity. In many cases the depth of 454 pyrosequencing coverage allowed us to define the entire cDNA sequence of a particular gene. Many new M. sexta genes are described including up to 36 new cytochrome P450s, some of which have been implicated in the metabolism of host plant-derived nicotine. New lepidopteran gene families such as the beta-fructofuranosidases, previously thought to be restricted to Bombyx mori, are also described. An unexpectedly high number of ESTs were involved in immunity, for example 39 contigs encoding serpins, and the increasingly appreciated role of the midgut in insect immunity is discussed. Similar studies of other tissues will allow for a tissue by tissue description of the M. sexta transcriptome and will form an essential complimentary step on the road to genome sequencing and annotation.

The influence of salmon surface mucus on the growth of Flavobacterium columnare

Flavobacterium columnare is the causative agent of columnaris disease. The presence of lesions on the gills, skin and fins of diseased fish suggests that F. columnare is able to utilize fish skin mucus as a substrate for growth and that exposure to this material would alter the expression of genes involved in the colonization of the outer surfaces of the fish. Growth, biofilm formation, extracellular protease production and changes in protein expression of F. columnare strain C#2 cultured in media supplemented with juvenile Atlantic salmon skin mucus were compared with the same media without mucus. C#2 was able to grow by using mucus as the sole nutrient source. Growth in mucus-containing media induced cells to grow as a biofilm and extracellular protease activity increased in mucus-containing cultures. SDS-PAGE protein profiles showed that expression of six extracellular proteins increased in mucus-containing media. These results demonstrate that salmon surface mucus promotes the growth of F. columnare and that exposure to mucus alters the growth characteristics of this bacterium with regard to protease production and biofilm formation. Further characterization of mucus-induced physiological changes will increase our understanding of the basis of virulence of this economically important fish pathogen.

Novel defect structures in nematic liquid crystal shells

We use double-emulsion drops to experimentally investigate the defect structures of spherical shells of nematic liquid crystals. We uncover a rich scenario of coexisting defect structures dictated by the unavoidable finite thickness of even the thinnest shell and by the thickness variation around the sphere. These structures are characterized by a varying number of disclination lines and pairs of surface point defects on the inner and outer surfaces of the nematic shell. In the limit of very thick shells the defect structure ultimately merges with that of a bulk nematic liquid crystal drop.

A randomized, placebo-controlled trial of repeated IV antibiotic therapy for Lyme encephalopathy

BACKGROUND

Optimal treatment remains uncertain for patients with cognitive impairment that persists or returns after standard IV antibiotic therapy for Lyme disease.

METHODS

Patients had well-documented Lyme disease, with at least 3 weeks of prior IV antibiotics, current positive IgG Western blot, and objective memory impairment. Healthy individuals served as controls for practice effects. Patients were randomly assigned to 10 weeks of double-masked treatment with IV ceftriaxone or IV placebo and then no antibiotic therapy. The primary outcome was neurocognitive performance at week 12-specifically, memory. Durability of benefit was evaluated at week 24. Group differences were estimated according to longitudinal mixed-effects models.

RESULTS

After screening 3368 patients and 305 volunteers, 37 patients and 20 healthy individuals enrolled. Enrolled patients had mild to moderate cognitive impairment and marked levels of fatigue, pain, and impaired physical functioning. Across six cognitive domains, a significant treatment-by-time interaction favored the antibiotic-treated group at week 12. The improvement was generalized (not specific to domain) and moderate in magnitude, but it was not sustained to week 24. On secondary outcome, patients with more severe fatigue, pain, and impaired physical functioning who received antibiotics were improved at week 12, and this was sustained to week 24 for pain and physical functioning. Adverse events from either the study medication or the PICC line were noted among 6 of 23 (26.1%) patients given IV ceftriaxone and among 1 of 14 (7.1%) patients given IV placebo; these resolved without permanent injury.

CONCLUSION

IV ceftriaxone therapy results in short-term cognitive improvement for patients with posttreatment Lyme encephalopathy, but relapse in cognition occurs after the antibiotic is discontinued. Treatment strategies that result in sustained cognitive improvement are needed.

The genome of black cottonwood, Populus trichocarpa (Torr. & Gray)

We report the draft genome of the black cottonwood tree, Populus trichocarpa. Integration of shotgun sequence assembly with genetic mapping enabled chromosome-scale reconstruction of the genome. More than 45,000 putative protein-coding genes were identified. Analysis of the assembled genome revealed a whole-genome duplication event; about 8000 pairs of duplicated genes from that event survived in the Populus genome. A second, older duplication event is indistinguishably coincident with the divergence of the Populus and Arabidopsis lineages. Nucleotide substitution, tandem gene duplication, and gross chromosomal rearrangement appear to proceed substantially more slowly in Populus than in Arabidopsis. Populus has more protein-coding genes than Arabidopsis, ranging on average from 1.4 to 1.6 putative Populus homologs for each Arabidopsis gene. However, the relative frequency of protein domains in the two genomes is similar. Overrepresented exceptions in Populus include genes associated with lignocellulosic wall biosynthesis, meristem development, disease resistance, and metabolite transport.

Crystallography on curved surfaces

We study static and dynamical properties that distinguish 2D crystals constrained to lie on a curved substrate from their flat-space counterparts. A generic mechanism of dislocation unbinding in the presence of varying Gaussian curvature is presented in the context of a model surface amenable to full analytical treatment. We find that glide diffusion of isolated dislocations is suppressed by a binding potential of purely geometrical origin. Finally, the energetics and biased diffusion dynamics of point defects such as vacancies and interstitials are explained in terms of their geometric potential.

Nematic textures in spherical shells

The equilibrium texture of nematic shells is studied as a function of their thickness. For ultrathin shells the ground state has four short 1/2 disclination lines but, as the thickness of the film increases, a three-dimensional escaped configuration composed of two pairs of half-hedgehogs becomes energetically favorable. We derive an exact solution for the nematic ground state in the one Frank constant approximation and study the stability of the corresponding texture against thermal fluctuations.

Pause point spectra in DNA constant-force unzipping

Under constant applied force, the separation of double-stranded DNA into two single strands is known to proceed through a series of pauses and jumps. Given experimental traces of constant-force unzipping, we present a method whereby the locations of pause points can be extracted in the form of a pause point spectrum. A simple theoretical model of DNA constant-force unzipping is presented, which generates theoretical pause point spectra through Monte Carlo simulation of the unzipping process. The locations of peaks in the experimental and theoretical pause point spectra are found to be nearly coincident below 6000 basepairs for unzipping the bacteriophage lambda-genome. The model only requires the sequence, temperature, and a set of empirical basepair binding and stacking energy parameters, and the good agreement with experiment suggests that pause point locations are primarily determined by the DNA sequence. The model is also used to predict pause point spectra for the bacteriophage phi X174 genome. The algorithm for extracting the pause point spectrum might also be useful for studying related systems which exhibit pausing behavior such as molecular motors.

Survival and resource utilization in liver transplant recipients: the impact of admission to the intensive care unit

The organ allocation system for liver transplantation was recently changed to address criticisms that it was too subjective and relied too heavily on total waiting time. The new system, Model for End-Stage Liver Disease and Pediatric Model for End-Stage Liver Disease (MELD/PELD), stratifies patients based on the risk of 3-month pretransplant mortality, allocating livers thereby. There is concern that such a scheme gives priority to the sickest patients, who may not enjoy good posttransplant outcomes. The aim of the present study was to compare the outcomes of liver transplant recipients who had been admitted to the intensive care unit (ICU) to those who had not. Admission to the ICU is considered here to be another indicator of the severity of illness. Patients who underwent liver transplantation at the Cleveland Clinic between January 1, 1993 and October 31, 1998 and were at least 18 years of age were coded for liver transplantation as status 2, 2A, and 2B (n = 112). These patients fell into three groups: those who had been admitted to an ICU before transplantation (group A, n = 16), those who had been admitted to the hospital but not to an ICU (group B, n = 63), and those who were living at home and had undergone an elective transplant (group C, n = 33). Clinical and demographic information (age, sex, race, disease severity, disease etiology, and cold ischemia time) were associated with patient survival, patient/graft survival, and posttransplant resource utilization (hospital length of stay and hospital charges). Age, sex, race, etiology of disease, and cold ischemia time were similar among the three groups. Patient survival, patient/graft survival, and hospital charges were not statistically different between the three groups. The median length of stay was statistically different only between groups B and C (P =.006). Our data support the idea that if severely ill patients with end-stage liver disease are selected appropriately, liver transplant outcomes are similar to those observed among subjects who are less ill and are transplanted electively from home.

Grain boundary scars and spherical crystallography

We describe experimental investigations of the structure of two-dimensional spherical crystals. The crystals, formed by beads self-assembled on water droplets in oil, serve as model systems for exploring very general theories about the minimum-energy configurations of particles with arbitrary repulsive interactions on curved surfaces. Above a critical system size we find that crystals develop distinctive high-angle grain boundaries, or scars, not found in planar crystals. The number of excess defects in a scar is shown to grow linearly with the dimensionless system size. The observed slope is expected to be universal, independent of the microscopic potential.

Crystalline order on a sphere and the generalized Thomson problem

We attack the generalized Thomson problem, i.e., determining the ground state energy and configuration of many particles interacting via an arbitrary repulsive pairwise potential on a sphere via a continuum mapping onto a universal long range interaction between angular disclination defects parametrized by the elastic (Young) modulus Y of the underlying lattice and the core energy E(core) of an isolated disclination. Predictions from the continuum theory for the ground state energy agree with numerical simulations of long range power law interactions of the form 1/r(gamma) (0<gamma<2) to four significant figures. The generality of our approach is illustrated by a study of grain boundary proliferation for tilted crystalline order and square lattices on the sphere.

Liver transplantation for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the commonest malignancies worldwide, and accounts for more than 1 million deaths annually. Identification of tumors early in the course of disease appears to be important for treatment, yet remains difficult to accomplish. Without treatment the prognosis is dismal with a median survival of 6-9 months. Partial hepatic resection is generally accepted as the treatment of choice for HCC with reported survival rates of up to 50% at 5 years. Unfortunately poor underlying liver function as well as tumor number or location preclude traditional hepatic resection in many cases. Total hepatectomy with transplantation (LT) has been advocated such cases, but the results have been variable. LT offers the advantage of radical tumor removal even in patients with multifocal disease or severe cirrhosis. Additionally, LT removes the possibility of metachronous lesions developing in the liver remnant and restores normal liver function. The critical limitation to advocating LT as primary oncotherapy in patients with HCC is the severe shortage of donor livers. Until organ availability improves, transplantation for HCC can only be offered to patients whose survival is predicted to be similar to that in patients transplanted for benign disease. This report reviews the current role and indications for liver transplantation as therapy for hepatocellular carcinoma.

Prediction of endometriosis with serum and peritoneal fluid markers: a prospective controlled trial

BACKGROUND

The objective of this prospective controlled trial was to investigate the ability of a group of serum and peritoneal fluid (PF) markers to predict, non-surgically, endometriosis.

METHODS AND RESULTS

Serum and PF samples were obtained from 130 women while undergoing laparoscopy for pain, infertility, tubal ligation or sterilization reversal. Concentrations of six cytokines [interleukin (IL)-1beta, IL-6, IL-8, IL-12, IL-13 and tumour necrosis factor (TNF)-alpha] were measured in serum and PF, and reactive oxygen species (ROS) in PF, and levels were compared among women who were allocated to groups according to their post-surgical diagnosis. Fifty-six patients were diagnosed with endometriosis, eight with idiopathic infertility, 27 underwent tubal ligation or reanastomosis (control group) and 39 were excluded due to bloody PF. Only serum IL-6 and PF TNF-alpha could be used to discriminate between patients with and without endometriosis with a high degree of sensitivity and specificity (P < 0.001). A threshold of 15 pg/ml PF TNF-alpha provided 100% sensitivity and 89% specificity (positive likelihood ratio of 9.1 and negative likelihood ratio of 0). A threshold of 2 pg/ml for serum IL-6 provided a sensitivity of 90% and specificity of 67% (positive likelihood ratio of 2.7 and negative likelihood ratio of 0.14).

CONCLUSIONS

By measuring serum IL-6 and PF TNF-alpha, it was possible to discriminate between patients with endometriosis and those without. Before these markers can be used as a non-surgical diagnostic tool, these data should be verified in a larger study.

Cell cycle arrest and differential gene expression in HT-29 cells exposed to an aqueous garlic extract

Epidemiological data show an inverse correlation between garlic consumption and the risk for colon cancer. To examine this relationship, HT-29 human adenocarcinoma cells were cultured in the presence and absence of an aqueous garlic extract. Garlic treatment resulted in a fraction of cells detaching from the culture flasks. These cells remained viable. Flow cell cytometry showed that untreated cells exhibited a normal distribution among phases of the cell cycle, with 12% of cells at the G2/M boundary. Of the garlic-treated cells remaining attached to the flask, 27% were present at the G2/M boundary. Treated cells that detached from the flask were found almost exclusively (89%) at the G2/M boundary. RNA fingerprinting and microarray analysis showed that expression of the gene for menin was twice as high in control cells as in detached treated cells. In contrast, expression of genes for epidermal growth factor receptor and integrin-alpha6 was nearly twice as high in detached treated cells as in control cells. These changes in gene expression were consistent with an arrest of the cell cycle at the G2/M boundary. Garlic's arrest of the cell cycle in human adenocarcinoma cells may explain in part its anticarcinogenic properties.

Anti-interleukin-2 receptor therapy in combination with mycophenolate mofetil is associated with more severe hepatitis C recurrence after liver transplantation

The pathogenesis of hepatitis C virus (HCV) recurrence after liver transplantation (LT) is poorly understood, but the cellular immune response is likely to have a major role. Daclizumab, an interleukin-2 receptor (IL-2R) antibody that blunts T-cell activation, leading to a decreased risk for cellular rejection, is used frequently in transplant recipients. The aim of this study is to evaluate the effect of daclizumab therapy on the incidence and severity of recurrent HCV. Forty-one liver transplant recipients (21 patients, HCV positive; 20 patients, HCV negative) at high risk for neurological or renal complications of calcineurin inhibitors were administered daclizumab, mycophenolate mofetil (MMF), and steroids in the early post-LT period, followed by tacrolimus and a steroid taper. All patients were followed up prospectively for graft function and disease recurrence with protocol liver biopsies day 7, month 4, and yearly. Compared with patients without HCV, patients with HCV administered daclizumab had greater 4-month serum alkaline phosphatase, total bilirubin, and alanine aminotransferase (ALT) levels. These biochemical differences resolved by 12 months, except for persistent elevation of ALT levels. Compared with a well-matched HCV control population, patients with HCV administered daclizumab were more likely to have an earlier onset of hepatitis, jaundice, and greater histological activity. Recurrent hepatitis progressed more rapidly in the daclizumab group; 45% developed advanced disease within 1 year. HCV viral load in the daclizumab group was significantly greater at both 4 months and 1 year. Results of this study suggest that the use of adjuvant IL-2R antibodies in combination with MMF in the early peritransplantation period may be associated with early recurrence of hepatitis C and more rapid histological progression of disease.

Organization, structure and evolution of the CYP2 gene cluster on human chromosome 19

The cytochrome P450 superfamily of mixed-function oxygenases has been extensively studied due to its many critical metabolic roles, and also because it is a fascinating example of gene family evolution. The cluster of genes on human chromosome 19 from the CYP2A, 2B, and 2F subfamilies has been previously described as having a complex organization and many pseudogenes. We describe the discovery of genes from three more CYP2 subfamilies inside the cluster, and assemble a complete map of the region. We comprehensively review the organization, structure, and expression of genes from all six subfamilies. A general hypothesis for the evolution of this complex gene cluster is also presented.

The immunopathogenesis of hepatitis C virus infection

The outcome of HCV infection is determined by the interaction between the virus and the host immune system. The persistence of infection in most HCV-infected individuals, despite the presence of HCV-directed antibodies, suggests that such antibodies fail to induce viral clearance. Patients with self-limited hepatitis C have evidence of a polyclonal, multispecific CD8+ T-cell response along with a coordinated CD4+ T-cell response that is associated with eradication of HCV infection. Cytokines are produced both locally within the liver and systemically and may play an important role in controlling viral replication and contributing to hepatocellular damage through amplification of a nonspecific immune response. In most patients, the humoral, cellular immune, and cytokine response seem insufficient to eradicate infection. In its attempt to clear the virus from the liver, the immune system contributes to the hepatocellular injury seem in most chronically infected patients. A better understanding of the host's immune response may provide further insight on the pathogenetic mechanisms involved in development of chronic hepatitis and aid the development of better therapeutic strategies.

Qualitative and quantitative differences in cuticular hydrocarbons between laboratory and field colonies of Pogonomyrmex barbatus

Ants held in the laboratory and field ants of the species Pogonomyrmex barbatus have quantitative differences in their cuticular hydrocarbons and a qualitative difference in their methyl-branched hydrocarbons. Laboratory-held workers showed twice the hydrocarbon content as field ants. This difference was mainly due to higher amounts of straight-chain alkanes and methyl-branched alkanes in laboratory ants, whereas the proportion of the alkenes remained the same for both groups. In addition to the absence of some hydrocarbons in the field colonies, one of the methyl-branched hydrocarbons differed in amount and branching pattern between the two groups of ants. Whereas, notable peaks of 2-methylalkanes were identified in ants kept in the laboratory, these compounds could not be identified in ants living in their natural habitat. However, a trace amount of 4-methyltriacontane was found in lieu of the 2-methyltriacontane counterpart in field ants. Possible explanations for both qualitative and quantitative differences are discussed.

Normal saline versus lactated Ringer's solution for intraoperative fluid management in patients undergoing abdominal aortic aneurysm repair: an outcome study

Metabolic acidosis and changes in serum osmolarity are consequences of 0.9% normal saline (NS) solution administration. We sought to determine if these physiologic changes influence patient outcome. Patients undergoing aortic reconstructive surgery were enrolled and were randomly assigned to receive lactated Ringer's (LR) solution (n = 33) or NS (n = 33) in a double-blinded fashion. Anesthetic and fluid management were standardized. Multiple measures of outcome were monitored. The NS patients developed a hyperchloremic acidosis and received more bicarbonate therapy (30 +/- 62 mL in the NS group versus 4 +/- 16 mL in the LR group; mean +/- SD), which was given if the base deficit was greater than -5 mEq/L. The NS patients also received a larger volume of platelet transfusion (478 +/- 302 mL in the NS group versus 223 +/- 24 mL in the LR group; mean +/- SD). When all blood products were summed, the NS group received significantly more blood products (P = 0.02). There were no differences in duration of mechanical ventilation, intensive care unit stay, hospital stay, and incidence of complications. When NS was used as the primary intraoperative solution, significantly more acidosis was seen on completion of surgery. This acidosis resulted in no apparent change in outcome but required larger amounts of bicarbonate to achieve predetermined measurements of base deficit and was associated with the use of larger amounts of blood products. These changes should be considered when choosing fluids for surgical procedures involving extensive blood loss and requiring extensive fluid administration.

IMPLICATIONS

Predominant use of 0.9% saline solution in major surgery has little impact on outcome as assessed by duration of mechanical ventilation, intensive care unit stay, hospital stay, and postoperative complications, but it does appear to be associated with increased perioperative blood loss.

Hexatic order and surface ripples in spherical geometries

In flat geometries, two-dimensional hexatic order has only a minor effect on capillary waves on a liquid substrate and on undulation modes in lipid bilayers. However, extended bond-orientational order alters the long-wavelength spectrum of these ripples in spherical geometries. We calculate this frequency shift and suggest that it might be detectable in lipid bilayer vesicles, at the surface of liquid metals, and in multielectron bubbles in liquid helium at low temperatures. Hexatic order also leads to a shift in the threshold for the fission instability induced in the later two systems by an excess of electric charge.

Immunohistochemical model to predict risk for coronary artery disease and failure in heart transplant patients

Transplant coronary artery disease is the leading cause of long-term morbidity and mortality in cardiac transplantation. We developed a model for early identification of patients who subsequently develop coronary artery disease and graft failure. Serial biopsies obtained from 141 cardiac allografts (5.5 +/- 0.1 biopsies/patient) during the first 3 months post-transplant were evaluated immunohistochemically for deposition of myocardial fibrin, depletion of arteriolar tissue plasminogen activator, presence of arterial/arteriolar endothelial activation markers, and changes in vascular antithrombin. An immunohistochemical risk score was developed with a minimum value of 0 (normal) and a maximum value of 4 (most abnormal). Scores of 0 (low risk), 0.5-3.0 (moderate risk), and 3.5-4.0 (high risk) were analyzed for association with graft failure and development, severity, and progression of coronary artery disease detected using serial coronary angiograms (3.9 +/- 0.2/patient). Allografts with high immunohistochemical risk scores in the first 3months post-transplant developed more coronary artery disease (p<0.001), developed coronary artery disease earlier (p<0.001), developed more severe disease (p<0.001), and showed more disease progression (p<0.001) than allografts with moderate or low scores. Allografts with high immunohistochemical risk scores in the first 3 months post-transplant failed more (p<0.001) and failed earlier (p<0.001) than allografts with moderate or low scores. The present study demonstrates that early changes in the microvasculature are associated with impending coronary artery disease and graft failure in cardiac allograft recipients and suggests that treatment needs to be instituted early after transplantation in order to improve outcome.

Work interrupted: a comparison of workplace interruptions in emergency departments and primary care offices

STUDY OBJECTIVE

We sought to determine the number of interruptions and to characterize tasks performed in emergency departments compared with those performed in primary care offices.

METHODS

We conducted an observational time-motion, task-analysis study in 5 nonteaching community hospitals and 22 primary care offices in 5 central Indiana cities. Twenty-two emergency physicians and 22 office-based primary care physicians (PCPs) were observed at work. The number of interruptions, tasks, simultaneous tasks, and patients concurrently managed were recorded in 1-minute increments during 150- to 210-minute observation periods.

RESULTS

Emergency physicians were interrupted an average of 9.7 times per hour compared with 3.9 times per hour for PCPs, for an average difference of 5.8 times per hour (95% confidence interval [CI] 4.2 to 7.4). PCPs spent an average of 11.4 minutes per hour performing simultaneous tasks compared with 6.4 minutes per hour for emergency physicians (average difference, 5.0 minutes; 95% CI 1.2 to 8.8). Emergency physicians spent an average of 37.5 minutes per hour managing 3 or more patients concurrently compared with 0.9 minutes per hour for PCPs. PCPs spent significantly more time performing direct patient care, and emergency physicians spent significantly more time in analyzing data, charting, and taking reports on patients.

CONCLUSION

Emergency physicians experienced more interruptions and managed more patients concurrently than PCPs. PCPs spent more time performing simultaneous tasks than emergency physicians. Our study suggests there are important ergonomic differences between emergency medicine and office-based primary care work environments that may require different training approaches, design considerations, and coping strategies.

Predictors of mortality and resource utilization in cirrhotic patients admitted to the medical ICU

BACKGROUND AND OBJECTIVE

Cirrhotic patients admitted to the medical ICU (MICU) are associated with high mortality rates and high resource utilization. This study identifies specific predictors of increased mortality and resource utilization and uses them to develop and validate prognostic models in cirrhotic patients admitted to the MICU.

METHODS

Cirrhotic patients admitted to the MICU were identified from the Critical Care Section database (January 1993 to October 1998). Clinical data were extracted from chart review including hospital course variables, mortality, and length of stay (LOS). Total cost per case (TCPC) was obtained from the Transition System INC: Multivariate logistic and linear regression analyses identified the independent predictors of increased mortality and resource utilization used for model building (MB) and model validation (MV).

RESULTS

A total of 582 cases were randomized to the MB and MV groups. Each group contained 240 cases after exclusion criteria were applied. The MICU mortality rate was 36.6%, and the in-hospital mortality rate was 49.0%. Acute physiology, age, and chronic health evaluation (APACHE) III score (odds ratio [OR], 4.7; 95% confidence interval [CI], 2.70 to 8.16; p < 0.001), mechanical ventilation (OR, 4.57; 95% CI, 2.35 to 8.34); p < 0.001), and the use of pressors (OR, 7.57; 95% CI, 4.35 to 13.18; p < 0.001) were independent predictors of MICU mortality. APACHE III score (OR, 4.96; 95% CI, 2.97 to 8.29; p < 0.001), the use of pressors (OR, 6.55; 95% CI, 3.66 to 11.72; p < 0.001), and acute renal failure (ARF) (OR, 4.31; 95% CI, 2.41 to 7.71; p < 0.001) were independent predictors of in-hospital mortality. Increased LOS in the MICU was associated with mechanical ventilation, ARF, bronchoscopy, bacteremia, use of pressors, transjugular intrahepatic portosystemic shunt (TIPS), and never received cardiopulmonary resuscitation (CPR) (p < 0.005). Source of admission, platelet transfusion, bacteremia, pneumonia, and never received CPR were independently associated with increased total LOS (p < 0.001). Mechanical ventilation, platelet transfusion, bronchoscopy, TIPS, sepsis, and never received CPR were independent predictors of increased TCPC (p < 0.001).

CONCLUSION

Simple prognostic models for mortality and resource utilization have been developed for cirrhotic patients admitted to the MICU.

Relationship between seminal white blood cell counts and oxidative stress in men treated at an infertility clinic

In semen, granulocytes are major producers of reactive oxygen species (ROS), which can damage sperm. The diagnosis of leukocytospermia is usually based on the World Health Organization (WHO) definition of 1 x 10(6) white blood cells per milliliter, but controversy remains over the minimum leukocyte level that impairs fertility. The goals of this study were to clarity the relationship between leukocyte count and oxidative stress and to establish the minimum leukocyte count associated with oxidative stress. To do so, we compared oxidative stress in semen samples with different leukocyte counts (by the Endtz test) after a simple wash-and-resuspend procedure and determined the correlation between leukocyte counts and oxidative stress (expressed as ROS-TAC score, a composite score calculated from ROS levels and total antioxidant capacity (TAC), both measured with chemiluminescence assays). ROS-TAC decreases as oxidative stress rises. We compared specimens from 271 men attending an infertility clinic and 28 healthy controls. About 9% of patients had WHO-defined leukocytospermia and an additional 16% had some leukocytes. Samples with no seminal leukocytes had significantly lower ROS levels and significantly higher ROS-TAC scores than samples with any seminal leukocytes, even very low levels. Oxidative stress was correlated with rising white blood cell (WBC) count (r = .39; P < .001). Receiver operating characteristics curves showed that ROS-TAC score would be fairly accurate at distinguishing between patients with any leukocytes and those with no leukocytes (area under the curve, 75%). In conclusion, oxidative stress occurs even in patients with very low seminal WBC counts (between 0 and 1 x 10(6)/mL) and rises with an increase in WBC count. Therefore, we are unable to determine a safe minimum WBC count; the presence of any WBCs is associated with oxidative stress and may therefore impair fertility. Complete removal of WBCs from semen samples used for assisted reproduction may help reduce oxidative stress.