1043 FRAGILITY FRACTURE RISK ASSESSMENT IN THE OLDER PERSON’S RAPID ACCESS CLINIC (OPRAC): A QUALITY IMPROVEMENT PROJECT

Background

One-in-two women and one-in-five men >50 years are expected to have an osteoporotic fracture during their lifetime. However, despite this 1-in-5 women who have broken a bone, break 3 or more before being diagnosed, highlighting the importance of early diagnosis.

Aim NICE recommends a fragility fracture risk assessment in all women aged >65 and men >75 years. However, during our review of patients attending OPRAC, we found that only 3% of patients had an assessment done. Therefore, the primary aim of this project was to improve risk assessment of fragility fractures in this setting.

Method

We analysed the data for patients attending OPRAC between 23.09.20–23.10.20 and 01.05.21–15.06.21. We captured 35 and 51 patients respectively and sought to identify what proportion of the population had an accurate height, weight and fragility fracture assessment. We carried out our QIP using the PDSA cycle. Our interventions consisted of departmental teaching, posters and inclusion of fracture risk assessment in our induction handbook.

Results

The risk assessment went up from 3% to 33% post-intervention and documentation of height and weight went up from 74% to 98%. We retrospectively calculated the FRAX score for every single patient to assess whether the patients were receiving the appropriate treatment according to their risk score. What was consistent across both cycles was that if a patient had a risk assessment done, they were far more likely to have the correct treatment—89% and 82% in cycles 1 and 2 vs. 54% and 30% in those who didn’t have an assessment.

Conclusion

The above highlights what we already know about the importance of early diagnosis and treatment of osteoporosis. The interventions we have implemented have made a difference however further incorporation of fragility fracture assessments in clinical protocols is needed to bring about sustained change.

Purely laparoscopic explant hepatectomy and hybrid laparoscopic/robotic graft implantation in living donor liver transplantation

This report describes a purely laparoscopic/robotic technique for successful living donor liver transplantation (LDLT). Purely laparoscopic explant hepatectomy followed by purely laparoscopic and robotic graft implantation can be performed in LDLT.

Associations between affect, craving, and smoking in Korean smokers: An ecological momentary assessment study

Cigarette smoking remains the largest cause of preventable death in the United States and worldwide. In South Korea and other Asian countries, a large proportion of males smoke, increasing the need to examine cigarette smoking in these populations. Research suggests that the association between positive affect and negative affect, and between affect and craving, may differ across cultures, and that it is useful to examine these associations using Ecological Momentary Assessment (EMA). South Korean smokers (N = 20, Mean Age = 21.15, 25% female) completed baseline questionnaires and downloaded an EMA app which prompted 4 random assessments (RAs) each day for 1-week. At each assessment, participants responded to items assessing momentary negative affect (NA) and positive affect (PA), craving, and number of cigarettes smoked since the previous EMA assessment. Linear mixed models (LMMs) were used to analyze EMA data (544 assessments), separating out between- and within- subject associations. There was a significant positive association between positive affect and negative affect at the between-subjects level. Both positive affect and negative affect were significantly positively associated with craving at between-subjects and within-subject levels. Craving was associated with subsequent smoking behavior at the within-subjects level. Overall, results suggest that associations between positive affect and negative affect may be different in South Korean smokers than in Western smokers, and that there are robust associations between both negative and positive affect and craving.

0192 Sleep Characteristics and Mood of Professional Esports Athletes: A Multi-National Study

Introduction

Esports is becoming increasingly professionalized, yet research on performance management is remarkably lacking. The present study aimed to investigate sleep and mood in professional esports athletes.

Methods

Participants were 17 professional esports athletes from South Korea (8), Australia (4) and the US (5) who played First Person Shooter games (mean age 20±3.5 years, 100% male). All participants wore a wrist-activity monitor for 7–14 days, and completed subjective sleep and mood questionnaires.

Results

Based on data from the wrist-activity monitory, participants averaged 409±37 minutes of total sleep time, and 87±1% of sleep efficiency per night. All participants had significantly delayed sleep patterns (Average bed Time 3:41 am and wake Time 11:11 am). Participants had an average SOL of 26.15 minutes and prolonged wake after sleep onset of 51.91 (±31.84) minutes. Korean players had significantly higher depression scores compared to the other groups (p=.006) and trained longer than the Australian or US teams (13.38 vs. 4.75 vs. 6.10 hours, respectively). Depression scores were strongly correlated with number of awakenings, wake after sleep onset and training time per day (ps<.05).

Conclusion

As the first exploratory study in the esports field, the study indicates that esports athletes show delayed sleep patterns and have prolonged wake after sleep onset. These sleep patterns may be associated with mood (depression) and training time. There may also be cultural differences that contribute to sleep disturbance in this population.

Support

Korean Society of Sleep Medicine

The effects of cortisol and adrenal androgen on bone mass in Asians with and without subclinical hypercortisolism

Analyses using the largest Korean cohort of adrenal incidentaloma (AI) revealed that subtle cortisol excess in premenopausal women and reduced dehydroepiandrosterone-sulfate (DHEA-S) in postmenopausal women and men are associated with bone mineral density (BMD) reduction in Asian patients with subclinical hypercortisolism (SH).

INTRODUCTION

Few studies evaluated bone metabolism in Asians with SH. We investigated associations of cortisol and DHEA-S, an adrenal androgen, with BMD in Asians with AI, with or without SH.

METHODS

We used cross-sectional data of a prospective multicenter study from Korea. We measured BMD, bone turnover markers, cortisol levels after 1-mg dexamethasone suppression test (1-mg DST), DHEA-S, and baseline cortisol to DHEA-S ratio (cort/DHEA-S) in 109 AI patients with SH (18 premenopausal, 38 postmenopausal women, and 53 men) and 686 with non-functional AI (NFAI; 59 premenopausal, 199 postmenopausal women, and 428 men).

RESULTS

Pre- and postmenopausal women, but not men, with SH had lower BMDs at lumbar spine (LS) than those with NFAI (P = 0.008~0.016). Premenopausal women with SH also had lower BMDs at the hip than those with NFAI (P = 0.009~0.012). After adjusting for confounders, cortisol levels after 1-mg DST demonstrated inverse associations with BMDs at all skeletal sites only in premenopausal women (β = - 0.042~- 0.033, P = 0.019~0.040). DHEA-S had positive associations with LS BMD in postmenopausal women (β = 0.096, P = 0.001) and men (β = 0.029, P = 0.038). The cort/DHEA-S had inverse associations with LS BMD in postmenopausal women (β = - 0.081, P = 0.004) and men (β = - 0.029, P = 0.011). These inverse associations of cort/DHEA-S remained significant after adjusting for cortisol levels after 1-mg DST (β = - 0.079~- 0.026, P = 0.006~0.029). In postmenopausal women, the odds ratios of lower BMD by DHEA-S and cort/DHEA-S was 0.26 (95% CI, 0.08-0.82) and 3.40 (95% CI, 1.12-10.33), respectively.

CONCLUSION

Subtle cortisol excess in premenopausal women and reduced DHEA-S in postmenopausal women and men may contribute to BMD reduction in Asians with SH.

Mathematical Modeling of Bacteria-Enabled Drug Delivery System Penetration into Multicellular Tumor Spheroids

Bacteria-based cancer treatment is a promising approach to address the need for targeted tumor therapies in an effort to avoid the systemic toxicity inherent in conventional chemotherapy. A number of bacterial strains have been shown to preferentially colonize tumors and impart therapeutic benefits. However, the physical underpinnings of bacteria intratumoral transport remain poorly studied. It is hypothesized that cell Iysis in hypoxic and necrotic regions of tumors creates a niche in which some bacteria thrive. To understand if preferential growth plausibly explains the experimentally observed bacterial colonization profiles, we have developed a mathematical model incorporating transport and growth dependent on tumor cell Iysate. We fit model parameters to experimental data, showing that our formulation captures experimentally observed trends. Moreover, we find that bacteria have a higher effective diffusivity than nanoparticles alone, demonstrating transport advantages to designing bacteria-based cancer therapy. This model serves as a first step towards building computational tools for designing optimized bacteria- based chemotherapeutic delivery systems.

Development of New Tracheal Prosthesis: Autogenous Mucosa-Lined Prosthesis Made from Polypropylene Mesh

Reliable tracheal or tissue graft has not been developed yet for the reconstruction of large, circumferential tracheal defects. Major limitations were anastomotic dehishence and stenosis, which were attributed to the poor epithelinisation of the prosthetic graft. We developed a new tracheal prosthesis that has a viable lined and well-vasculised mucosa. The prosthesis consists of Prolene® mesh reinforced with polypropylene rings, and is coated with gelatin. In addition, we lined the luminal surface of the prosthesis with transplanted autogenous oral mucosa and wrapped the prosthesis with greater omentum. Animal experiments were performed using 10 adult mongrel dogs. The transplanted mucosa and wrapped greater omentum tightly adhered to the prosthesis to make a single unit within two weeks. The mucosa survived well, was well vasculised by new vessels from greater omentum and showed normal histology. Complete surgical resection and replacement of a thoracic trachea (3 cm in length, 6 tracheal rings) were carried out in 2 dogs, which survived well with normal activity. We concluded that this highly biocompatible tracheal prosthesis could be very useful for step-wise reconstruction of tracheal defects.

A Case Of Huge Brunner's Gland Adenoma With Acute Bleeding Treated By Endoscopic Resection

Brunner's gland adenoma is a rare benign small bowel neoplasm and it represents 10% of small bowel benign tumor. Most of adenoma manifest as polypoidal, multiple and size does not exceed 1 cm and mostly asymptomatic, but the lesion larger than 1 ㎝ is solitary and can cause bleeding, obstruction, intussusception and there are some reports of showing malignant transformation. Until the present, there are two cases of over 8㎝ huge Brunner's gland adenoma in Korea and each of their chief complaint was abdominal discomfort and melena, but there is no case report of over 8 ㎝ Brunner's gland adenoma accompanied with acute bleeding as seen in this case. We diagnosed an 8 ㎝ sized, huge duodenal Brunner's gland adenoma which accompanied with acute bleeding and treated it by endoscopic resection using an IT-knife, successfully.

Co-transplantation of bone marrow-derived endothelial progenitor cells improves revascularization and organization in islet grafts

Bone marrow-derived early endothelial progenitor cells (BM-EPCs) are a clinical tool for enhancing revascularization. However, the therapeutic efficacy of co-transplantation of BM-EPC with islets has not been investigated. In this study, marginal mass islets were co-transplanted with or without BM-EPCs under the kidney capsules of syngeneic streptozotocin-induced diabetic mice. Using green fluorescent protein transgenic (GFP-Tg) mice as BM-EPC and islet donors or recipients, the role of EPCs in revascularization was assessed for graft morphology, vascular density and fate of EPCs by immunohistochemistry. Islet-EPC co-transplantation improved the outcome of islet transplantation as measured by glucose tolerance, serum insulin level and diabetes reversal rate, compared with transplantation of islets alone. Between groups, the morphology of islet grafts showed significant differences in size and composition of grafted endocrine tissues. Significantly more vessel density derived from donors and recipients was detected with islet-EPC co-transplantation. Abundant GFP-Tg mice-derived BM-EPCs (GFP-EPCs) were observed in or around islet grafts and incorporated into CD31-positive capillaries. Remaining GFP-EPCs expressed VEGF. In conclusion, co-transplantation of islets with BM-EPCs could improve the outcome of marginal mass islet transplantation by promoting revascularization and preserving islet morphology.

[The prevalence of Barrett's esophagus and the comparison of Barrett's esophagus with cardiac intestinal metaplasia in the health screening at a secondary care hospital]

BACKGROUND/AIMS

The purpose of this study was to estimate the prevalence of Barrett's esophagus (BE) and its association with reflux esophagitis (RE) and peptic ulcer disease detected by free charge endoscopy which was covered by the National Health Insurance at a secondary care hospital, and to compare the results of the biopsy of BE with that of cardiac intestinal metaplasia (CIM).

METHODS

A total of 4,002 patients underwent endoscopy from March 2010 to December 2012. BE was diagnosed if there was histologically proven specialized intestinal metaplasia, and CIM was diagnosed if intestinal metaplasia was accompanied with chronic gastritis.

RESULTS

Four hundred twenty four patients underwent endoscopic biopsy, and the prevalence of BE was 1.0% (42/4,002). The mean age and the proportion of males in BE were significantly higher than those of the rest of study population, and BE had slight tendency related to RE than the rest of study population. CIM was observed in 34 patients and BE and CIM showed similar results, regarding age, sex and association with RE. The mean length of endoscopic Barrett's mucosa of BE group was 9.2±5.1 mm, and it was similar to that of CIM.

CONCLUSIONS

The prevalence of BE in the secondary care hospital was not low, and old age and male sex were significantly associated with BE. Because BE was observed in about 10% of biopsied patients and CIM was observed in a similar percentage with BE, the precise targeted biopsy is warranted and the biopsy method should be reestablished through the large prospective study of multiple secondary care hospitals.

Counting small hypointense spots confounds the quantification of functional islet mass based on islet MRI

Iron-containing fragmented islets or free iron released from dying cells could confound the interpretation of MRI of iron nanoparticle-labeled islets. Exclusion of small hypointense spots could be a useful strategy to avoid such artifact. We investigated whether this strategy could improve the estimation of functioning islet mass after islet transplantation. Using a rat syngeneic intraportal islet transplantation model, we quantitatively assessed the relationships between total area, number of hypointense spots on MRI that belong to each size quartile and glycemic control of the recipients. The total area of hypointense spots on MRI was greater in the recipients that achieved diabetes reversal (p = 0.002), whereas the total number of hypointense spots was not different (p = 0.757). Exclusion of small hypointense spots improved the association between the number of hypointense spots and the blood glucose level of the recipients (p < 0.001). Ex-vivo imaging and histologic study confirmed that some small hypointense spots represent the phagocytosed free iron. Exclusion of small hypointense spots improved the quantification of the functional islet mass based on islet MRI. This would be a useful principle in the development of an algorithm to estimate functioning islet mass based on islet MRI.

Changes in prevalence of Helicobacter pylori infection after subtotal gastrectomy

BACKGROUND/AIMS

There have been few reports comparing pre and postoperative prevalence of Helicobacter pylori infection and gastritis in patients with gastric cancer surgery.

METHODOLOGY

Seventy patients with primary gastric cancer were identified to be infected with Helicobacter pylori preoperatively and tested for Helicobacter pylori infection after subtotal gastrectomy. We analyzed changes in Helicobacter pylori infectivity and histological features of gastric mucosa.

RESULTS

The overall spontaneous regression rate of Helicobacter pylori infection was 38.6% (27/70). The mean time between surgery and follow-up tests was 1.02±0.5 years. The activity and chronic inflammation scores were significantly decreased in regression group. In non-regression group, there was no significant difference in activity scores, but the chronic inflammation score was significantly increased. There were no significant changes in atrophic gastritis and intestinal metaplasia scores in either group. The grade of Helicobacter pylori infection was significantly decreased in non-regression group.

CONCLUSIONS

The spontaneous regression rate of Helicobacter pylori infection after subtotal gastrectomy was 38.6% (27/70), it occurred in larger scale of patients and it occurred earlier (1.02±0.5 years) than in previous studies. We suggest that further prospective study on spontaneous regression rate of Helicobacter pylori infection after subtotal gastrectomy and its mechanism is needed in the future.

Dual therapy trial using esomeprazole and amoxicillin as third-line rescue therapy for Helicobacter pylori infection

BACKGROUND/AIMS

The purpose of this study was to evaluate the efficacy and tolerability of dual therapy consisting of esomeprazole and amoxicillin as a rescue therapy for Helicobacter pylori infection.

METHODS

From December 2009 to August 2010, 21 patients who experienced two consecutive eradication failures were included. They received esomeprazole (40 mg, b.i.d.) and amoxicillin (1,000 mg, b.i.d.) for 14 days as a third eradication regimen. Compliance and side effects were determined from an interview. H. pylori status was evaluated using the (13)C urea breath test at least 6 weeks after treatment.

RESULTS

The mean age of the patients was 59 years and included 52% males. Indications for treatment were functional dyspepsia (61.9%), peptic ulcer disease (28.6%), and gastric adenoma (9.5%). H. pylori was eradicated in 14 of 21 (66.7%) patients. Minor side effects were reported in three of the 21 patients (14.3%). These side effects consisted mainly of nausea and epigastric discomfort.

CONCLUSIONS

A 2-week course of dual therapy failed to show satisfactory results in third-line H. pylori eradication, but it was very safe and tolerable. Therefore, dual therapy constitutes an encouraging empirical strategy for the elderly and infirm patients with multiple previous eradication failures.

Comparison of Direct Medical Care Costs Between Erosive Reflux Disease and Non-erosive Reflux Disease in Korean Tertiary Medical Center

Background/Aims

Gastroesophageal reflux disease is one of the most common and frequent chronic disease requiring considerable cost. We investigated the medical care costs in the erosive reflux disease (ERD) and non-erosive reflux disease (NERD).

Methods

The risk factors and the direct medical care costs were analyzed retrospectively in the ERD (178 patients) and NERD (183 patients) groups for a follow up period of 2 years.

Results

Logistic regression analysis showed that the ERD was more frequent in the groups of male gender, alcohol consumption, higher body mass index (≥25 kg/m²), hiatal hernia, and higher triglyceride levels (≥150 mg/dL). The direct medical care costs per person for 2 years were found to be $384.8 (ERD) and $412.9 (NERD) without statistically significant differences (p = 0.364). However, 9.3% (17/183) of the NERD patients had visited the emergency room compared to 3.4% (6/178) of the ERD patients (p = 0.029). In addition, more NERD patients were hospitalized than ERD patients (p = 0.006), and because of the longer hospitalization period, the medical costs in NERD patients were higher than ERD patients (p = 0.038).

Conclusions

In spite of the different risk factors for ERD and NERD, total direct medical care costs were similar between the ERD and NERD group. However, more visits to emergency room and longer hospitalization period with more hospitalization costs in NERD patients account for the differences in medical service and usage distribution between the 2 groups.

Phase diagram of quarter-filled band organic salts [EDT-TTF-CONMe2]2X, X=AsF6 and Br

An investigation of the P-T phase diagram of the quarter-filled organic conductors, [EDT-TTF-CONMe2]2X is reported on the basis of transport and NMR studies of two members, X=AsF6 and Br of the family. The strongly insulating character of these materials in the low-pressure regime has been attributed to a remarkably stable charge-ordered state confirmed by 13C NMR and the only existence of 1/4 Umklapp e-e scattering favoring a charge ordering instead of the 1D Mott localization seen in (TMTTF)2X and (TMTSF)2X which are 1/4-filled compounds with dimerization. A nonmagnetic insulating phase instead of the spin density wave state is stabilized in the deconfined regime of the phase diagram. This sequence of phases observed under pressure may be considered as a generic behavior for 1/4-filled conductors with correlations.

93Nb NMR spin echo spectroscopy in single crystal NbSe3

We report electric field induced phase displacements of the charge density wave (CDW) in a single crystal of NbSe3 using 93Nb NMR spin-echo spectroscopy. CDW polarizations in the pinned state induced by unipolar and bipolar pulses are linear and reversible up to at least E = (0.96)ET. The polarizations have a broad distribution extending up to phase angles of order 60 degrees for electric fields close to threshold. No evidence for polarizations in excess of a CDW wavelength or for a divergence in polarization near ET are observed. The results are consistent with elastic depinning models, provided that the critical regime expected in large systems is not observable.

Life cycle assessment part 1: framework, goal and scope definition, inventory analysis, and applications

Sustainable development requires methods and tools to measure and compare the environmental impacts of human activities for the provision of goods and services (both of which are summarized under the term "products"). Environmental impacts include those from emissions into the environment and through the consumption of resources, as well as other interventions (e.g., land use) associated with providing products that occur when extracting resources, producing materials, manufacturing the products, during consumption/use, and at the products' end-of-life (collection/sorting, reuse, recycling, waste disposal). These emissions and consumptions contribute to a wide range of impacts, such as climate change, stratospheric ozone depletion, tropospheric ozone (smog) creation, eutrophication, acidification, toxicological stress on human health and ecosystems, the depletion of resources, water use, land use, and noise-among others. A clear need, therefore, exists to be proactive and to provide complimentary insights, apart from current regulatory practices, to help reduce such impacts. Practitioners and researchers from many domains come together in life cycle assessment (LCA) to calculate indicators of the aforementioned potential environmental impacts that are linked to products-supporting the identification of opportunities for pollution prevention and reductions in resource consumption while taking the entire product life cycle into consideration. This paper, part 1 in a series of two, introduces the LCA framework and procedure, outlines how to define and model a product's life cycle, and provides an overview of available methods and tools for tabulating and compiling associated emissions and resource consumption data in a life cycle inventory (LCI). It also discusses the application of LCA in industry and policy making. The second paper, by Pennington et al. (Environ. Int. 2003, in press), highlights the key features, summarises available approaches, and outlines the key challenges of assessing the aforementioned inventory data in terms of contributions to environmental impacts (life cycle impact assessment, LCIA).

Gut-derived sepsis occurs when the right pathogen with the right virulence genes meets the right host: evidence for in vivo virulence expression in Pseudomonas aeruginosa

OBJECTIVE

To define the putative role of the PA-I lectin/adhesin, a binding protein of Pseudomonas aeruginosa, on lethal gut-derived sepsis after surgical stress, and to determine if this protein is expressed in vivo in response to physical and chemical changes in the local microenvironment of the intestinal tract after surgical stress.

SUMMARY BACKGROUND DATA

Previous work from the authors' laboratory has established that lethal gut-derived sepsis can be induced after the introduction of P. aeruginosa into the cecum of mice after a 30% hepatectomy. This effect does not occur when P. aeruginosa is introduced into the cecum of sham operated control mice. Previous experiments further established that the mechanism of this effect is due to the presence of the PA-I lectin/adhesin of P. aeruginosa, which induces a permeability defect to a lethal cytotoxin of P. aeruginosa, exotoxin A.

METHODS

Three strains of P. aeruginosa, one lacking functional PA-I, were tested in two complementary systems to assess virulence. Strains were tested for their ability to adhere to and alter the permeability of cultured human colon epithelial cells, and for their ability to induce mortality when injected into the cecum of mice after a 30% hepatectomy. To determine if PA-I is "in vivo expressed" when present in the cecal environment after hepatectomy, strains were retrieved from the cecum of sham-operated and hepatectomy-treated mice 24 and 48 hours after their introduction into the cecum and their PA-I expression was assessed.

RESULTS

Results indicated that PA-I plays a putative role in lethal gut-derived sepsis in the mouse, because strains lacking functional PA-I had an attenuated effect on cultured human epithelial cells, and were nonlethal when injected into the cecum of mice after 30% surgical hepatectomy. Furthermore, surgical stress in the form of hepatectomy significantly altered the intestinal microenvironment, resulting in an increase in luminal norepinephrine associated with an increase in PA-I expression in retrieved strains of P. aeruginosa. Co-incubation of P. aeruginosa with norepinephrine increased PA-I expression in vitro, suggesting that norepinephrine plays a role in the observed response in vivo.

CONCLUSIONS

Lethal gut-derived sepsis may occur when intestinal pathogens express virulence determinants in response to environmental signals indicating host stress. In this regard, the PA-I lectin/adhesin of P. aeruginosa appears to be a specific example of in vivo virulence expression in colonizing pathogens in the intestinal tract in response to surgical stress.

Failure to induce inhibition of cyclin A and up-regulation of p21 expression in phorbol ester-resistant U937 cells by phorbol ester

Differentiation resistant U937 cells were derived from parental U937 cells by selecting for continuously growing U937 cells in cell cultures continuously exposed to phorbol 12 myristate 13-acetate (PMA). Unlike in other known PMA resistant U937, the basal expression of protein kinase C (PKC) isozymes in these PMA resistant cells (R-U937) was significantly decreased. Subsequent analyses revealed differences between the wild type U937 and the R-U937 cells with respect to G1 phase arrest, which seemed to occur in U937 because of low levels of cdk2 kinase activity. This abolished cdk2 kinase activity is mainly due to inhibition of cdk2 phosphorylation, cyclin A down-regulation and cyclin dependent kinase inhibitor p21 up-regulation. Our data suggest that events down-stream of PKC activation may mediate cell cycle control. Thus, the R-U937 cells could be useful for further PKC mediated cell cycle control studies.

Blue light activates potassium-efflux channels in flexor cells from Samanea saman motor organs via two mechanisms

Light-induced leaflet movement of Samanea saman depends on the regulation of membrane transporters in motor cells. Blue light (BL) stimulates leaflet opening by inducing K(+) release from the flexor motor cells. To elucidate the mechanism of K(+)-efflux (K(D))-channel regulation by light, flexor motor cell protoplasts were patch-clamped in a cell-attached configuration during varying illumination. Depolarization elicited outward currents through single open K(D) channels. Changes in cell membrane potential (E(M)) were estimated by applying voltage ramps and tracking the change of the apparent reversal potential of K(D)-channel current. BL shifted E(M) in a positive direction (i.e. depolarized the cell) by about 10 mV. Subsequent red light pulse followed by darkness shifted E(M) oppositely (i.e. hyperpolarized the cell). The BL-induced shifts of E(M) were not observed in cells pretreated with a hydrogen-pump inhibitor, suggesting a contribution by hydrogen-pump to the shift. BL also increased K(D)-channel activity in a voltage-independent manner as reflected in the increase of the mean net steady-state patch conductance at a depolarization of 40 mV relative to the apparent reversal potential (G(@40)). G(@40) increased by approximately 12 pS without a change of the single-channel conductance, possibly by increasing the probability of channel opening. Subsequent red-light and darkness reversed the change in G(@40). Thus, K(+) efflux, a determining factor for the cell-volume decrease of flexor cells, is regulated by BL in a dual manner via membrane potential and by an independent signaling pathway.

Protective effects of the green tea polyphenol (-)-epigallocatechin gallate against hippocampal neuronal damage after transient global ischemia in gerbils

Recent studies have shown that green tea polyphenols reduce free radical-induced lipid peroxidation. Oxygen free radical injury plays an important role in neuronal damage induced by brain ischemia and reperfusion. The purpose of this study was to examine whether (-)-epigallocatechin gallate (EGCG) would reduce neuronal damage after transient global ischemia in the gerbils because EGCG has a potent antioxidant property as a green tea polyphenol. To produce transient global ischemia, both common carotid arteries were occluded for 3 min with microaneurysmal clips. The gerbils were treated with EGCG (10, 25, or 50 mg/kg, i.p.) immediately after ischemia. Neuronal cell damage in the hippocampal CA1 region was evaluated quantitatively 5 days after ischemia by a blinded investigator. EGCG at the dose of 10 mg/kg failed to reduce hippocampal neuronal damage. However, EGCG when administered at the dose of 25 or 50 mg/kg significantly reduced hippocampal neuronal damage in a dose-dependent manner (P<0.001, respectively). The present results show that the green tea polyphenol, EGCG, has a neuroprotective effect against neuronal damage following global ischemia in the gerbils.

Oligogalacturonic acid and chitosan reduce stomatal aperture by inducing the evolution of reactive oxygen species from guard cells of tomato and Commelina communis

Stomatal opening provides access to inner leaf tissues for many plant pathogens, so narrowing stomatal apertures may be advantageous for plant defense. We investigated how guard cells respond to elicitors that can be generated from cell walls of plants or pathogens during pathogen infection. The effect of oligogalacturonic acid (OGA), a degradation product of the plant cell wall, and chitosan (beta-1,4-linked glucosamine), a component of the fungal cell wall, on stomatal movements were examined in leaf epidermis of tomato (Lycopersicon esculentum L.) and Commelina communis L. These elicitors reduced the size of the stomatal aperture. OGA not only inhibited light-induced stomatal opening, but also accelerated stomatal closing in both species; chitosan inhibited light-induced stomatal opening in tomato epidermis. The effects of OGA and chitosan were suppressed when EGTA, catalase, or ascorbic acid was present in the medium, suggesting that Ca(2+) and H(2)O(2) mediate the elicitor-induced decrease of stomatal apertures. We show that the H(2)O(2) that is involved in this process is produced by guard cells in response to elicitors. Our results suggest that guard cells infected by pathogens may close their stomata via a pathway involving H(2)O(2) production, thus interfering with the continuous invasion of pathogens through the stomatal pores.

The epidemiology of cancer of the small bowel

Despite its anatomical location between two regions of high cancer risk, the small bowel rarely develops a malignant tumor. However, in recent years, small bowel cancer incidence rates have begun to rise. The purpose of this review is to explore the descriptive and analytic epidemiology of small bowel cancer for those factors that protect this organ and those factors associated with loss of this protection. Within the small intestine, the sites at the highest risk are the duodenum, for adenocarcinomas, and the ileum, for carcinoids and lymphomas. In industrialized countries, small bowel cancers are predominantly adenocarcinomas; in developing countries, lymphomas are much more common. The incidence of small bowel cancer rises with age and has generally been higher among males than among females. The risk factors for small bowel cancer include dietary factors similar to those implicated in large bowel cancer, cigarette smoking, alcohol intake, and other medical conditions, including Crohn's disease, familial adenomatous polyposis, cholecystectomy, peptic ulcer disease, and cystic fibrosis. The protective factors may include rapid cell turnover, a general absence of bacteria, an alkaline environment, and low levels of activating enzymes of precarcinogens. Adenocarcinomas of the small and large bowel are similar in risk factors and geographic distribution but not in recent time trends; colorectal cancer incidence rates in the United States have been falling since the mid-1980s. Small bowel lymphoma may be associated with infectious agents, such as HIV. Given the differences in anatomic and geographic location among histological subtypes, much may be learned from well-designed, histology-specific epidemiological and genetic studies of cancer of the small bowel.

Actin Filaments Modulate Both Stomatal Opening and Inward K+-Channel Activities in Guard Cells of Vicia faba L

Actin antagonists have previously been shown to alter responses of Commelina communis stomata to physiological stimuli, implicating actin filaments in the control of guard cell volume changes (M. Kim, P.K. Hepler, S.-O. Eun, K.S. Ha, Y. Lee [1995] Plant Physiol 109: 1077-1084). Since K+ channels in the guard cell play an important role in stomatal movements, we examined the possible regulation of K+-channel activities by the state of actin polymerization. Agents affecting actin polymerization altered light-induced stomatal opening and inward K+-channel activities measured by patch clamping in Vicia faba. Cytochalasin D, which induces depolymerization of actin filaments, promoted light-induced stomatal opening and potentiated the inward K+ current in guard cell protoplasts. Phalloidin, a stabilizer of filamentous actin, inhibited both light-induced stomatal opening and inward K+ current. Inward K+-channel activities in outside-out membrane patches showed responses to these agents that support results at the whole-cell current level, suggesting that cytochalasin D facilitates and phalloidin inhibits K+ influx in intact guard cells, thus resulting in enhancement and inhibition of stomatal opening, respectively. To our knowledge, this is the first report that provides evidence that actin filaments may regulate an important physiological process by modulating the activities of ion channels in plant cells.

Cryptic signals and the fidelity of V(D)J joining

V(D)J recombination is responsible for the de novo creation of antigen receptor genes in T- and B-cell precursors. To the extent that lymphopoiesis takes place throughout an animal's lifetime, recombination errors present an ongoing problem. One type of aberrant rearrangement ensues when DNA sequences resembling a V(D)J joining signal are targeted by mistake. This study investigates the type of sequence likely to be subject to mistargeting, the level of joining-signal function associated with these sequences, and the number of such cryptic joining signals in the genome.

Abscisic Acid-Induced Phosphoinositide Turnover in Guard Cell Protoplasts of Vicia faba

Guard cell protoplasts of Vicia faba treated with 10 [mu]M (+)abscisic acid (ABA) in the light exhibited a 20% decrease in diameter within 1.5 h, from 24.1 to 19.6 [mu]m. Within 10 s of administration of ABA, a 90% increase in levels of inositol 1,4,5-trisphosphate was observed, provided that cells were treated with Li+, an inhibitor of inositol phosphatase activity, prior to incubation. Concomitantly, levels of 32P-labeled phosphatidylinositol 4,5-bisphosphate and phosphatidylinositol 4-phosphate decreased 20% compared to levels in control cells; levels of label in the membrane lipids phosphatidylcholine, phosphatidylethanolamine, and phosphatidylglycerol did not change significantly in response to ABA treatment. These results show that phosphoinositide turnover is activated in response to ABA in guard cells. We conclude that phosphoinositide signaling is likely to be a step in the biochemical cascade that couples ABA to guard cell shrinking and stomatal closure.