The tether function of the anoctamins

The core functions of the anoctamins are Cl- channel activity and phosphatidylserine (and perhaps other lipids) scrambling. These functions have been extensively studied in various tissues and cells. However, another function of the anoctamins that is less recognized and minimally explored is as tethers at membrane contact sites. This short review aims to examine evidence supporting the localization of the anoctamins at membrane contact sites, their tether properties, and their functions as tethers.

PtdSer as a signaling lipid determined by privileged localization of ORP5 and ORP8 at ER/PM junctional foci to determine PM and ER PtdSer/PI(4)P ratio and cell function

The membrane contact site ER/PM junctions are hubs for signaling pathways, including Ca2+ signaling. Phosphatidylserine (PtdSer) mediates various physiological functions; however, junctional PtdSer composition and the role of PtdSer in Ca2+ signaling and Ca2+-dependent gene regulation are not understood. Here, we show that STIM1-formed junctions are required for PI(4)P/PtdSer exchange by ORP5 and ORP8, which have reciprocal lipid exchange modes and function as a rheostat that sets the junctional PtdSer/PI(4)P ratio. Targeting the ORP5 and ORP8 and their lipid transfer ORD domains to PM subdomains revealed that ORP5 sets low and ORP8 high junctional PI(4)P/PtdSer ratio that controls STIM1-STIM1 and STIM1-Orai1 interaction and the activity of the SERCA pump to determine the pattern of receptor-evoked Ca2+ oscillations, and consequently translocation of NFAT to the nucleus. Significantly, targeting the ORP5 and ORP8 ORDs to the STIM1 ER subdomain reversed their function. Notably, changing PI(4)P/PtdSer ratio by hydrolysis of PM or ER PtdSer with targeted PtdSer-specific PLA1a1 reproduced the ORPs function. The function of the ORPs is determined both by their differential lipid exchange modes and by privileged localization at the ER/PM subdomains. These findings reveal a role of PtdSer as a signaling lipid that controls the available PM PI(4)P, the unappreciated role of ER PtdSer in cell function, and the diversity of the ER/PM junctions. The effect of PtdSer on the junctional PI(4)P level should have multiple implications in cellular signaling and functions.

The sun, cholesterol and Orai1 conspire in melanoma

How does skin cancer become metastatic? A recent study by Gross et al (2022) reports a novel pathway by which UV radiation acts on cholesterol biosynthesis to control Ca2+ influx by Orai1, causing protein O-GlcNAcylation that promotes transformation to invasive melanoma.

Delays in diagnostic tests used to identify transthyretin amyloid cardiomyopathy (ATTR-CM) in the EU4 + UK

Background

Transthyretin amyloid cardiomyopathy (ATTR-CM) is an underdiagnosed, progressive disease characterised by amyloid protein deposits building in the left ventricle. The symptoms of ATTR-CM are like those associated with heart failure, and specialised tests are needed to identify ATTR-CM.

Purpose

This paper examines the tests used to identify ATTR-CM in France, Germany, Italy, Spain and United Kingdom and the time between these tests.

Methods

Ipsos' ATTR-CM Therapy Monitor was fielded between November 2020 and December 2020, with 210 (FR: 46, DE: 40, IT: 43, ES: 42, UK: 39) treating doctors providing data on 320 (FR: 71, DE: 63, IT: 64, ES: 63, UK: 59) patients diagnosed with ATTR-CM. Ipsos analysed information provided on the diagnostic tests ordered for the 320 patients to understand how ATTR-CM is diagnosed across the five markets, and also tracked the order in which the tests were conducted, across four batteries, to understand the flow of the diagnostic procedures.

Results

Overall, the patients in our study went through 6 diagnostic tests on average before receiving a confirmed ATTR-CM diagnosis via Echocardiogram (ECHO) with strain imaging (83%), Cardiac Magnetic Resonance Imaging MRI (75%), Genetic tests (69%), Laboratory tests (59%), Scintigraphy tests (52%), and Biopsy tests (51%) as the top tests ordered. Overall, 15% of the reported patients had an unknown order of tests. Patients in Germany, France and Italy received the most tests on average (FR: 6, DE: 7, IT: 6, ES: 5 and UK: 5). Patients in Germany also experienced the shortest delays between batteries of tests (3.2 wks. between 1st and 2nd batteries; 3.9 wks. between 2nd and 3rd batteries) and were most likely to receive a Genetic test (84%) or Biopsy test (68%) to confirm diagnosis. In comparison, patients in Spain experienced the longest testing delays (7.3 wks. between 1st and 2nd batteries; 5.8 wks. between 2nd and 3rd batteries) and went through only 5 diagnostic tests before receiving a confirmed diagnosis.

Across the markets, 59% of doctors experienced a decline in ability to diagnose patients with ATTR-CM due to COVID-19, with the degree of impact differing drastically by region (FR: 43%, DE: 20%, IT: 79%, ES: 88% and UK: 64%). With doctors indicating that 16% of their patients were untreated due to late diagnosis with advanced disease (FR: 15%, DE: 10%, IT: 16%, ES: 20% and UK: 21%), identifying suspected ATTR-CM and running the necessary tests to diagnose ATTR-CM early are essential.

Conclusion

Overall, the patients reported on in this study received upwards of 6 diagnostic tests before confirmation of ATTR-CM, with 4.5 weeks between each battery of tests. In addition to regional nuances in regard to test choice, we see evidence that there are country level differences between how quickly patients receive diagnostic tests. Further research is needed to identify ways of increasing the speed of testing and subsequent diagnosis.

Funding Acknowledgement

Type of funding sources: None. Diagnostic Procedures by Region

228 Outcomes of Gallstone Complications During the COVID Pandemic

Background

The Intercollegiate General Surgery Guidance on COVID-19 recommended either non-surgical management or cholecystostomy drains for the management of acute biliary disease replacing gold standard practice of early laparoscopic cholecystectomy within 1 week of index admission with drainage reserved for high-risk patients where surgery is not appropriate.

Method

This is the retrospective study presenting the impact of gallstone disease in our unit during five months of the COVID- 19 pandemic (March 2020-August 2020) compared with the equivalent period in 2019.

Results

Patients presenting to the HPB unit with a coded diagnosis of gallstones were included and during the study period 1447 patients presented compared with 1413 in 2019. In 2020 compared with 2019 there was a significant decrease in patients presenting with cholecystitis (240 vs 313; p = 0.031) but no significant difference in patients presenting due to gallbladder perforation (44 vs 51). Interestingly the numbers of cholecystostomies were comparable, with 11 in 2020 and 15 in 2019 representing significantly less than the 7.2% figure published by Peckham-Cooper et al.

Conclusions

In our study there was a decrease in patients with cholecystitis and perforation and there was an increase in patients with gallstone pancreatitis, increase waiting lists with increase in the incidence of serious complications. In our trust we currently have 656 patients awaiting cholecystectomy compared to 280 in august 2019. With the recent elevation of the alert level to 4 and increased government restrictions, a consistent National approach is required to mitigate these risks.

Modeling of Statistical Variation Effects on DRAM Sense Amplifier Offset Voltage

With the downscaling in device sizes, process-induced parameter variation has emerged as one of the most serious problems. In particular, the parameter fluctuation of the dynamic random access memory (DRAM) sense amplifiers causes an offset voltage, leading to sensing failure. Previous studies indicate that the threshold voltage mismatch between the paired transistors of a sense amplifier is the most critical factor. In this study, virtual wafers were generated, including statistical V_T variation. Then, we numerically investigate the prediction accuracy and reliability of the offset voltage of DRAM wafers using test point measurement for the first time. We expect that this study will be helpful in strengthening the in-line controllability of wafers to secure the DRAM sensing margin.

88 Prevalence Of SARS-COVID-19 Serum Igg Antibodies Amongst Staff on An Acute Surgical Unit

Background

The United Kingdom now has one of the highest death rates from COVID 19, with over 40,000 deaths (1). It has been posited that the identification of care workers with immunity or increased resistance could be important in developing future strategies.

Method

This was a retrospectively conducted survey of general surgical staff at a tertiary surgical unit.

Results

We surveyed 215 staff that had undergone antibody testing. Of the 175/215 who reported contact with COVID-19 positive patients, 6/215 had a positive PCR result and 15/215 reported a positive antibody test. Only 3/6 that had a positive PCR test demonstrated antibodies.

Conclusions

Our “immunity” rate of 7% is extremely low and is concerning especially in respect of the anticipated “herd immunity” which would mitigate many of the issues presently being confronted and it is likely to be many months at least before this makes realistic contribution. Continued testing for the presence of COVID-19 antibodies will contribute to crucial seroprevalence data that can be used by public health bodies whose advice will necessarily evolve as increasing data sets become available.

Outcomes of gallstone complications during the COVID pandemic

As data and metadata from the SARS-CoV-2 pandemic mature, the true impact on non-cancer, non-emergency surgical practice is becoming apparent. The authors present data on the impact of gallstone disease in their unit during 5 months of the COVID-19 pandemic (March 2020 to August 2020) compared with the equivalent period in 2019. Although the total number of patients presenting with gallstone disease was comparable, there was a decrease in patients with cholecystitis and perforation (although it is possibly too early for these to have presented), and there was a small but worrying increase in patients with gallstone pancreatitis. With the recent increase in alert level to 4 and increased government restrictions in an attempt to avoid a second national lockdown, a consistent national approach is required to mitigate these risks.

Blood lead levels in relation to smoking and chronic obstructive pulmonary disease (COPD): a study from Korean National Health and Nutrition Examination Survey (KNHANES)

Background

Lead exposure is a resurgent environmental issue globally. Smoking can be a source of lead exposure, although the majority of lead poisonings originate from workplace exposures. However, no study has been undertaken concerning the blood lead levels based on the chronic obstructive pulmonary disease (COPD), smoking status, and other risk factors of COPD. This cross-sectional study was conducted to investigate the blood lead levels according to COPD and clinical variables associated with COPD.

Methods

Data (total number =53,829) were collected from the Korean National Health and Nutrition Examination Survey (IV in 2008 and 2009, V in 2010–2012, and VI in 2013). Multivariable linear regression analyses were performed to determine variables associated with elevated blood lead levels.

Results

Univariate regression analysis showed that male sex, older age, smoking, occupation level, income level, education level, and presence of COPD were related to higher blood lead levels, whereas the other co-morbidities including diabetes, hypertension, cerebral stroke, osteoporosis, asthma, and depression were not related (P<0.05). Multivariable regression analysis demonstrated that older age, male sex, smoking, occupation, and education level were independently associated with higher blood lead levels (P<0.05).

Conclusions

Smoking status, occupation, and education level along with old age and male sex were independently associated with higher blood lead levels; however, COPD was not after adjustment of all confounding factors.

Ca2+ Signaling in Exocrine Cells

Calcium (Ca²⁺) and cyclic AMP (cAMP) signaling cross talk and synergize to stimulate the cardinal functions of exocrine cells, regulated exocytosis, and fluid and electrolyte secretion. This physiological process requires the organization of the two signaling pathways into complexes at defined cellular domains and close placement. Such domains are formed by membrane contact sites (MCS). This review discusses the basic properties of Ca²⁺ signaling in exocrine cells, the role of MCS in the organization of cell signaling and in cross talk and synergism between the Ca²⁺ and cAMP signaling pathways and, finally, the mechanism by which the Ca²⁺ and cAMP pathways synergize to stimulate epithelial fluid and electrolyte secretion.

The Prevention of Contrast Induced Nephropathy by Sarpogrelate: a Prospective Randomized Controlled Clinical Trial

BACKGROUND

Although some strategies are used for prophylaxis of contrast induced nephropathy, their efficacy is not fully established. Sarpogrelate can relieve vasospasm and have anti-inflammatory action. This study examined whether sarpogrelate reduces the incidence of contrast induced nephropathy (CIN) or subsequent renal impairment during four weeks after coronary angiography compared with a control group.

METHODS

Seventy-four participants with chronic renal failure were randomly assigned to the sarpogrelate or control group. Patients assigned to the sarpogrelate group received oral saporogelate from 24 hours before contrast exposure up to one month after contrast exposure. The primary outcome of this study was the incidence of CIN within 48 hours after exposure to the contrast agent.

RESULTS

Thirty-one subjects in the control group and 35 subjects in the sarpogrelate group were used for the analysis. Cumulative CIN occurred numerically more at 48 hours in the sarpogrelate group and less at one month without statistical significance (11.4% vs. 6.5% at 48 hours and 11.4% vs. 16.1% at one month, respectively). Baseline renal function was similar in both groups, but the estimated glomerular filtration rate (eGFR) was lower in the sarpogrelate group at 12 and 48 hours compared with the control group (45.6 vs. 54.7 mL/min/1.73m²; P = 0.023 and 39.9 vs. 50.6 mL/min/1.73m²; P = 0.020, respectively). At one month, the eGFR became comparable between the two groups because the eGFR was aggravated in the control group and maintained in the sarpogrelate group.

CONCLUSION

This study failed to demonstrate that sarpogrelate has a renoprotective effect against contrast induced acute kidney injury.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01165567.

Anoctamin 8 tethers endoplasmic reticulum and plasma membrane for assembly of Ca2+ signaling complexes at the ER/PM compartment

Communication and material transfer between membranes and organelles take place at membrane contact sites (MCSs). MCSs between the ER and PM, the ER/PM junctions, are the sites where the ER Ca²⁺ sensor STIM1 and the PM Ca²⁺ influx channel Orai1 cluster. MCSs are formed by tether proteins that bridge the opposing membranes, but the identity and role of these tethers in receptor-evoked Ca²⁺ signaling is not well understood. Here, we identified Anoctamin 8 (ANO8) as a key tether in the formation of the ER/PM junctions that is essential for STIM1-STIM1 interaction and STIM1-Orai1 interaction and channel activation at a ER/PM PI(4,5)P₂-rich compartment. Moreover, ANO8 assembles all core Ca²⁺ signaling proteins: Orai1, PMCA, STIM1, IP₃ receptors, and SERCA2 at the ER/PM junctions to mediate a novel form of Orai1 channel inactivation by markedly facilitating SERCA2-mediated Ca²⁺ influx into the ER. This controls the efficiency of receptor-stimulated Ca²⁺ signaling, Ca²⁺ oscillations, and duration of Orai1 activity to prevent Ca²⁺ toxicity. These findings reveal the central role of MCSs in determining efficiency and fidelity of cell signaling.

A Technology-Computer-Aided-Design-Based Reliability Prediction Model for DRAM Storage Capacitors

A full three-dimensional technology-computer-aided-design-based reliability prediction model was proposed for dynamic random-access memory (DRAM) storage capacitors. The model can be used to predict the time-dependent dielectric breakdown as well as leakage current of a state-of-the-art DRAM storage capacitor with a complex three-dimensional structure.

Enhanced recovery after surgery for liver resection

INTRODUCTION

Enhanced recovery after surgery (ERAS) reduces postoperative length of hospital stay and patient stress response to liver surgery. The aim of the present study was to evaluate the efficacy and feasibility of an ERAS programme for liver resection.

METHODS

A multidisciplinary ERAS protocol was implemented for both open and laparoscopic liver resection in a tertiary hospital in Hong Kong. The clinical outcomes of patients who underwent liver resection and underwent the ERAS perioperative programme were compared with those who received a conventional perioperative programme between September 2015 and July 2016. Propensity score matching analysis was used to minimise background differences.

RESULTS

A total of 20 patients who underwent liver resection were recruited to the ERAS programme. Their clinical outcomes were compared with another 20 patients who received hepatectomy under a conventional perioperative programme after propensity score matching. The ERAS programme was associated with a significantly shorter length of hospital stay (P=0.033) without an increase in complication rates in patients who underwent open liver resection. There was no such significant association in patients who underwent laparoscopic liver resection. No patients required readmission in this cohort.

CONCLUSIONS

The ERAS perioperative programme for liver resection is safe and feasible. It significantly shortened the hospital stay after open liver resection but not after laparoscopic liver resection.

Recombinant growth hormone therapy for prepubertal children with idiopathic short stature in Korea: a phase III randomized trial

PURPOSE

Several studies have evaluated the effects of growth hormone (GH) on auxological and biochemical parameters in children with non-GH-deficient, idiopathic short stature (ISS). This study evaluated the efficacy and safety of Growtropin^®-II (recombinant human GH) in Korean patients with ISS.

METHODS

This was a 1-year, open-label, multicenter, phase III randomized trial of Growtropin^®-II in Korean patients with ISS. In total, 70 prepubertal subjects (39 males, 31 females) between 4 and 12 years of age were included in the study. All patients were naive to GH treatment.

RESULTS

Annual height velocity was significantly higher in the treatment group (10.68 ± 1.95 cm/year) than the control group (5.72 ± 1.72, p < 0.001). Increases in height and weight standard deviation scores (SDSs) at 26 weeks were 0.63 ± 0.16 and 0.64 ± 0.46, respectively, for the treatment group, and 0.06 ± 0.15 and 0.06 ± 0.28, respectively, for the control group (p < 0.001). Serum insulin-like growth factor (IGF-1) and insulin-like growth factor binding protein-3 (IGFBP-3) increased significantly in the treatment group at week 26 compared to baseline. However, the SDS for body mass index (BMI) at 26 weeks did not change significantly in either group. Growtropin^®-II was well tolerated and safe over 1 year of treatment.

CONCLUSIONS

One-year GH treatment for prepubertal children with ISS demonstrated increased annualized velocity, height and weight SDSs, and IGF-1 and IGFBP-3 levels, with a favorable safety profile. Further evaluations are needed to determine the optimal dose, final adult height, and long-term effects of ISS treatment.

Overexpression of WNK1 in POMC-expressing neurons reduces weigh gain via WNK4-mediated degradation of Kir6.2

"With no lysine" (WNK) kinases have been shown to regulate various ion transporters in various tissues, but studies on the function of WNK kinases in the brain have been limited. In this study, we discovered that WNK1 and WNK4 in POMC-expressing neuronal cells in WNK1 overexpressed transgenic mice (WNK1 TG) decrease appetite via degradation of Kir6.2. Weight gain after 20 weeks of age was delayed in WNK1 TG mice as a result of reduced food intake. Expression of WNK1 and proopiomelanocortin (POMC) was higher in POMC-expressing neurons in the hypothalamus of WNK1 TG mice than in WT mice. Immunostaining of serial sections of the hypothalamus revealed that POMC-expressing neurons were smaller in WNK1 TG mice than in WT mice. In addition, expression of Kir6.2 was significantly reduced in WNK1 TG mice. Overexpression and knockdown of WNK4 demonstrated that WNK4 regulates protein expression of Kir6.2 via protein-protein interaction. Accordingly, reduced age-dependent weight gain of WNK1 TG mice seems to be related with the decreased Kir6.2 expression via WNK1- and WNK4-regulated protein stability of Kir6.2.

Lipids at membrane contact sites: cell signaling and ion transport

Communication between organelles is essential to coordinate cellular functions and the cell's response to physiological and pathological stimuli. Organellar communication occurs at membrane contact sites (MCSs), where the endoplasmic reticulum (ER) membrane is tethered to cellular organelle membranes by specific tether proteins and where lipid transfer proteins and cell signaling proteins are located. MCSs have many cellular functions and are the sites of lipid and ion transfer between organelles and generation of second messengers. This review discusses several aspects of MCSs in the context of lipid transfer, formation of lipid domains, generation of Ca²⁺ and cAMP second messengers, and regulation of ion transporters by lipids.

Ca2+ influx at the ER/PM junctions

Ca²⁺ influx across the plasma membrane is a key component of the receptor-evoked Ca²⁺ signaling that mediate numerous cell functions and reload the ER after partial or full ER Ca²⁺ store depletion. Ca²⁺ influx is activated in response to Ca²⁺ release from the ER, a concept developed by Jim Putney, and the channels mediating the influx are thus called store-operated Ca²⁺ influx channels, or SOCs. The molecular identity of the SOCs has been determined with the identification of the TRPC channels, STIM1 and the Orai channels. These channels are targeted to, operate and are regulated when at the ER/PM junctions. ER/PM junctions are a form of membrane contact sites (MCSs) that are present in all parts of the cells, where the ER makes contacts with cellular membranes and organelles. MCSs have many cellular functions, and are the sites of lipid and Ca²⁺ transport and delivery between organelles. This short review discusses aspects of MCSs in the context of Ca²⁺ transport.

Robotic surgery for thyroid disease

While conventional open thyroidectomy techniques are the most widely performed thyroid operation, they produce an anterior neck scar that may be difficult to conceal. The endoscopic thyroidectomy was developed to decrease the cosmetic impact on the patient and has the advantage of reducing the incidence of anterior neck hypoesthesia and paresthesia. However, this procedure has some drawbacks, which motivated surgeons to develop a new operation method. Robotic thyroidectomy is a relatively new approach for treating differentiated thyroid cancer. Over the last few years, robotic thyroidectomies have become more common. Robotic thyroidectomies are a feasible, safe alternative for managing thyroid disease that has remarkable functional benefits beyond those of conventional open methods. The applications for robotic thyroidectomy have expanded to include increasingly advanced cases, which will consequently change the thyroid surgery paradigm in the future.

Early intervention in thyroidectomy scars: demographics, symptoms, and prevention

OBJECTIVE

Although hypertrophic scars are cosmetically problematic for patients following thyroidectomy, the associated risk factors are not well defined. Our objective was to determine the factors associated with hypertrophic scar development following thyroidectomy.

METHOD

A retrospective chart review was performed collecting data on sex, age, body mass index (BMI), operation site, skin characteristics (pigmentation, erythema, elasticity, and hydration), and clinical scar characteristics (itching, tightening, induration, adhesion, and oedema). It was also noted if the patient had early scar intervention with intralesional steroid injection or non-ablative fractional laser irradiation, and preventive topical treatment agents. The effects of these factors were analysed using univariate and multivariate analyses.

RESULTS

Data from 1141 patients showed the incidence of hypertrophic scars was 13.9%. Significant variables in univariate analysis were combined for multivariate analysis. Young age, high BMI, itching, tightening, induration, and adhesion were associated with hypertrophic scar formation. Early scar intervention, as well as the use of preventive topical agents, were associated with decreased hypertrophic scar formation.

CONCLUSION

Based on our results, we suggest that dermatologists consider using non-ablative fractional laser, intralesional steroid injection, and topical preventive agents to lower the incidence of hypertrophic scars, especially in young patients or those with high BMI and/or clinical symptoms such as itching, tightening, induration, and adhesion.

Efficacy of two different self-expanding nitinol stents for atherosclerotic femoropopliteal arterial disease (SENS-FP trial): study protocol for a randomized controlled trial

Background

There have been few randomized control trials comparing the incidence of stent fracture and primary patency among different self-expanding nitinol stents to date. The SMART™ CONTROL stent (Cordis Corp, Miami Lakes, Florida, United States) has a peak-to-valley bridge and inline interconnection, whereas the COMPLETE™-SE stent (Medtronic Vascular, Santa Rosa, California, United States) crowns have been configured to minimize crown-to-crown interaction, increasing the stent's flexibility without compromising radial strength. Further, the 2011 ESC (European society of cardiology) guidelines recommend that dual antiplatelet therapy with aspirin and a thienopyridine such as clopidogrel should be administered for at least one month after infrainguinal bare metal stent implantation. Cilostazol has been reported to reduce intimal hyperplasia and subsequent repeat revascularization. To date, there has been no randomized study comparing the safety and efficacy of two different antiplatelet regimens, clopidogrel and cilostazol, following successful femoropopliteal stenting.

Methods/Design

The primary purpose of our study is to examine the incidence of stent fracture and primary patency between two different major representative self-expanding nitinol stents (SMART™ CONTROL versus COMPLETE™-SE) in stenotic or occlusive femoropopliteal arterial lesion. The secondary purpose is to examine whether there is any difference in efficacy and safety between aspirin plus clopidogrel versus aspirin plus cilostazol for one month following stent implantation in femoropopliteal lesions. This is a prospective, randomized, multicenter trial to assess the efficacy of the COMPLETE™-SE versus SMART™ CONTROL stent for provisional stenting after balloon angioplasty in femoropopliteal arterial lesions. The study design is a 2x2 randomization design and a total of 346 patients will be enrolled. The primary endpoint of this study is the rate of binary restenosis in the treated segment at 12 months after intervention as determined by catheter angiography or duplex ultrasound.

Discussion

This trial will provide powerful insight into whether the design of the COMPLETE™-SE stent is more fracture-resistant or effective in preventing restenosis compared with the SMART™ CONTROL stent. Also, it will determine the efficacy and safety of aspirin plus clopidogrel versus aspirin plus cilostazol in patients undergoing stent implantation in femoropopliteal lesions.

Trial registration

Registered on 2 April 2012 with the National Institutes of Health Clinical Trials Registry (ClinicalTrials.gov identifier# NCT01570803).

Unique features of non-obstructive emphysema and pure airway obstruction

SETTING

Emphysema without airway obstruction or airway obstruction without emphysema are often detected clinically, although they are commonly co-existent. We therefore tested the hypothesis that non-obstructive emphysema and pure airway obstruction have unique features.

METHODS

A case-control observation study was undertaken retrospectively in a patient cohort at a single centre. Among 2662 subjects who underwent chest computed tomography and pulmonary function tests, we enrolled 90 patients with non-obstructive emphysema, 119 with pure airway obstruction, 81 with obstructive emphysema and 2031 subjects as normal controls. The features of the four groups were analysed and compared.

RESULTS

Higher serum homocysteine (13.4 ± 7.4 vs. 11.6 ± 4.6 mol/l), higher rate of osteoporosis (15.8% vs. 4.5%), higher leukocyte count, higher male ratio, lower serum albumin and lower body mass index were observed in subjects with non-obstructive emphysema than in controls (P < 0.05). In multiple logistic regression analysis of groups without airway obstruction, osteoporosis, hyperhomocysteinaemia, hypoalbuminaemia and higher leukocyte count were independent factors associated with non-obstructive emphysema (P < 0.05).

CONCLUSION

Hyperhomocysteinaemia, hypoalbuminaemia, osteoporosis and higher leukocyte count were independent predictors of non-obstructive emphysema.

Cellular and plasma uptake of parenteral omega-3 rich lipid emulsion fatty acids in patients with advanced pancreatic cancer

BACKGROUND & AIMS

Omega-3 rich fatty acids (n-3FA) have powerful anti-inflammatory and anti-neoplastic properties. Previous studies have investigated plasma and cellular uptake of oral and parenteral n-3FA regimens. These have shown that n-3FA undergo rapid uptake into cells which is sustained for the length of the treatment course. The aim of this study was to investigate long-term uptake of prolonged, regular treatment courses of parenteral n-3FA which has not been previously reported.

METHODS

As part of a phase II single-arm trial, patients with advanced pancreatic cancer were treated with gemcitabine plus parenteral n-3FA rich lipid emulsion (up to 100 g) each week for three consecutive weeks with a subsequent rest week. This was repeated for up to six months in total for each patient. Pre-treatment serum and erythrocyte cell membrane (ECM) pellet samples were obtained each week for the entire treatment course of each patient. Post-treatment samples were obtained for the first two cycles only to assess rapid uptake. Fatty acid methyl esters (FAME) were produced and analysed using gas chromatography. FAME proportions as a total of sample lipid composition for each class were plotted and the results analysed using a linear regression coefficient model.

RESULTS

There was rapid and significant uptake of EPA and DHA FAME into plasma Non-Esterified Fatty Acids (NEFA) and EPA into ECM pellets in post-treatment samples (median increase of 1.06%, 0.65% and 0.05% respectively). There was significant reduction in n-6 fatty acid FAMEs and DHA in ECM pellets (decrease of 0.31% and 0.8% respectively- p = 0.031 for all). There was significant sustained uptake of EPA and DHA FAME into ECM pellets over the cohort's pooled treatment course with corresponding reduction in the n-6:n-3 ratio.

CONCLUSIONS

Prolonged regular parenteral n-3FA administration results in rapid and sustained cellular uptake. This regimen is appropriate for therapies aimed at increasing n-3FA content of cellular membranes and reduction of the n-6:n-3 ratio.

WNK4 inhibits plasma membrane targeting of NCC through regulation of syntaxin13 SNARE formation

WNK4, a serine/threonine kinase, plays a critical role in the expression of membrane proteins in the cell surface; however, the underlying mechanism of WNK4 is not clear. Here, we demonstrate that WNK4 inhibits the fusion of plasma membrane delivering vesicle with sorting/recycling endosome through disrupting SNARE formation of syntaxin13, an endosomal t-SNARE and VAMP2, the v-SNARE in plasma membrane delivering vesicle. Their interaction and co-localization were enhanced by hyperosmotic stimulation which is known for WNK4 activation. The kinase domain of WNK4 interacts with the transmembrane domain (TM) of syntaxin13 and this interaction was abolished when the TM was replaced with that of syntaxin16. Interestingly, cell fractionation using sucrose gradients revealed that WNK4 inhibited the formation of the syntaxin13/VAMP2 SNARE complex in the endosomal compartment, but not syntaxin16/VAMP2 or syntaxin13/VAMP7. Syntaxin13 was not phosphorylated by WNK4 and WNK4KI also showed the same binding strength and similar inhibitory regulation on SNARE formation of syntaxin13. Physiological relevance of this mechanism was proved with the expression of NCC (Na(+) C1(-) co-transporter) in the cell surface. The inhibiting activity of WNK4 on surface expression of NCC was abolished by syntaxin13 siRNA transfection. These results suggest that WNK4 attenuates PM targeting of NCC proteins through regulation of syntaxin13 SNARE complex formation with VAMP2 in recycling and sorting endosome.

Opposite regulatory effects of TRPC1 and TRPC5 on neurite outgrowth in PC12 cells

The transient receptor potential (TRPC) family of Ca²⁺ permeable, non-selective cation channels is abundantly expressed in the brain, and can function as store-operated (SOC) and store-independent channels depending on their interaction with the ER Ca²⁺ sensor STIM1. TRPC1 and TRPC5 have critical roles in neurite outgrowth, however which of their functions regulate neurite outgrowth is unknown. In this study, we investigated the effects of TRPC channels and their STIM1-induced SOC activity on neurite outgrowth of PC12 cells. We report that PC12 cell differentiation down-regulates TRPC5 expression, whereas TRPC1 expression is retained. TRPC1 and TRPC5 interact with STIM1 through the STIM1 ERM domain. Transfection of TRPC1 and TRPC5 increased the receptor-activated Ca²⁺ influx that was markedly augmented by the co-expression of STIM1. Topical expression of TRPC1 in PC12 cells markedly increased neurite outgrowth while that of TRPC5 suppressed neurite outgrowth. Suppression of neurite outgrowth by TRPC5 requires the channel function of TRPC5. However, strikingly, multiple lines of evidence show that the TRPC1-induced neurite outgrowth was independent of TRPC1-mediated Ca²⁺ influx. Thus, a) TRPC1 and TRPC5 similarly increased Ca²⁺ influx but only TRPC1 induced neurite outgrowth, b) the constitutively STIM1(D76A) mutant that activates Ca²⁺ influx by TRPC and Orai channels did not increase neurite outgrowth, c) co-expression of TRPC5 with TRPC1 suppressed the effect of TRPC1 on neurite outgrowth, d) and most notable, channel-dead pore mutant of TRPC1 increased neurite outgrowth to the same extent as TRPC1(WT). Suppression of TRPC1-induced neurite outgrowth by TRPC5 was due to a marked reduction in the surface expression of TRPC1. We conclude that the regulation of neurite outgrowth by TRPC1 is independent of Ca²⁺ influx and TRPC1-promoted neurite outgrowth depends on the surface expression of TRPC1. It is likely that TRPC1 acts as a scaffold at the cell surface to assemble a signaling complex to stimulate neurite outgrowth.

Preoperative anxiety and pain sensitivity are independent predictors of propofol and sevoflurane requirements in general anaesthesia

BACKGROUND

Psychological factors are thought to drive inter-patient variations in anaesthetic and analgesic requirements. This cross-sectional study investigated whether preoperative psychological factors can predict anaesthetic requirements and postoperative pain.

METHODS

Before total thyroidectomy, 100 consecutive women completed the Spielberger's State-Trait Anxiety Inventory (STAI) and the pain sensitivity questionnaire (PSQ). Target-controlled propofol was administered for induction of anaesthesia, and sevoflurane-oxygen-air was given to maintain equal depths of anaesthesia, as determined by bispectral index (BIS) monitoring.

RESULTS

Patients with higher anxiety scores (state and trait) required greater amounts of propofol to reach light (BIS=85) and moderate (BIS=75) levels of sedation, but only trait anxiety was significantly associated with propofol requirements in reaching a deep level of sedation (BIS=65). The MAC-hour of sevoflurane was significantly correlated only with PSQ scores. The postoperative pain intensity was significantly correlated with both STAI and PSQ.

CONCLUSIONS

Preoperative anxiety and pain sensitivity are independent predictors of propofol and sevoflurane requirements in general anaesthesia. Anaesthetic and analgesic doses could be modified based on the patient's preoperative anxiety and pain sensitivity.

Emphysema as a risk factor for the outcome of surgical resection of lung cancer

It is unclear whether emphysema, regardless of airflow limitation, is a predictive factor associated with survival after lung cancer resection. Therefore, we investigated whether emphysema was a risk factor associated with the outcome after resection for lung cancer. This study enrolled 237 patients with non small cell lung cancer with stage I or II who had surgical removal. Patient outcome was analyzed based on emphysema. Emphysema was found in 43.4% of all patients. Patients with emphysema were predominantly men and smokers, and had a lower body mass index than the patients without emphysema. The patients without emphysema (n=133) survived longer (mean 51.2+/-3.0 vs. 40.6+/-3.1 months, P=0.042) than those with emphysema (n=104). The univariate analysis showed a younger age, higher FEV(1)/FVC, higher body mass index, cancer stage I, and a lower emphysema score were significant predictors of better survival. The multivariate analysis revealed a younger age, higher body mass index, and cancer stage I were independent parameters associated with better survival, however, emphysema was not. This study suggests that unfavorable outcomes after surgical resection of lung cancer should not be attributed to emphysema itself.

Serum angiopoietin-1 as a prognostic marker in resected early stage lung cancer

PURPOSE

We evaluated the clinical significance of angiopoietins and vascular endothelial growth factor (VEGF) in patients with resected early stage lung cancer.

PATIENTS AND METHODS

The study enrolled 101 patients with completely resected non-small cell lung cancer (NSCLC) of stage I or II, along with 70 healthy volunteers. Serum concentrations of angiopoietin-1, angiopoietin-2, and VEGF were measured with an ELISA. Immunohistochemical expression of angiopoietin-1 was compared with the microvessel density on the lung cancer tissues.

RESULTS

The patients had lower serum angiopoietin-1 (32.1+/-9.9 ng/mL vs. 39.0+/-10.8 ng/mL, p<0.001), higher angiopoietin-2 (1949.2+/-1099.4 pg/mL vs. 1498.6+/-650.0 pg/mL, p<0.01), and higher VEGF (565.1+/-406.3 pg/mL vs. 404.6+/-254.8 pg/mL, p<0.01) levels than the controls. The angiopoietin-2 level was higher in stage II than in stage I patients (p<0.05). The levels of angiopoietin-1 (r=0.28) and angiopoietin-2 (r=0.36) each correlated with the VEGF level. Patients with a higher level of angiopoietin-1 (> or =31.2 ng/mL) had better disease-specific and relapse-free survival than those with a lower angiopoietin-1 level (<31.2 ng/mL). Angiopoietin-1 expression negatively correlated with the microvessel density.

CONCLUSION

Serum angiopoietin-1 is a potential marker for predicting postoperative survival and recurrence in patients with early stage NSCLC.

Incidence and clinical behavior of papillary thyroid carcinoma in renal allograft recipients: a single center experience

The chronic use of immunosuppressive therapy in transplant recipients increases the long-term risk for carcinoma. However, there is insufficient knowledge regarding the incidence and biological behavior of papillary thyroid carcinomas (PTC) in renal allograft recipients. In the present study we examined the incidence and biological behavior of PTCs among 1739 patients transplanted between January 1986 and December 1999 who had been followed for a mean period of 137 months (range, 84-238 months). During the follow-up, 129 (7.4%) recipients were identified to display posttransplantation malignancies, including 12 (0.7%) with PTCs. The 6 male and 6 female patients had a mean age of 41 years (range, 23-57 years). Nine cases (incidentalomas) were diagnosed based on ultrasonographic (US) screening. Eight of those 9 were TNM stage I, 2 of the 3 clinical carcinomas were TNM stage IVa. During a mean follow-up of 94 months (range, 18-159 months), 2 (16.7%) PTC patients developed locoregional recurrence, but no patients showed distant metastases. These data showed that recipients had a higher incidence of PTC compared with the general Korean population (0.7% vs 0.02%). Posttransplantation PTC tended to show no difference in gender distribution, and was often associated with aggressive lymphatic metastasis. However, most incidentalomas showed favorable treatment outcomes. In conclusion, routine surveillance of the thyroid gland using US screening is recommended to ensure early detection, treatment, and favorable prognosis of PTC.

Growth arrest-specific gene 6 expression in human breast cancer

Growth arrest-specific gene 6 (Gas6), identified in 1995, acts as the ligand to the Axl/Tyro3 family of tyrosine kinase receptors and exerts mitogenic activity when bound to these receptors. Overexpression of the Axl/Tyro3 receptor family has been found in breast, ovarian and lung tumours. Gas6 is upregulated 23-fold by progesterone acting through the progesterone receptor B (PRB). Recently, Gas6 has been shown to be a target for overexpression and amplification in breast cancer. Quantitative real-time PCR analysis was used to determine the levels of Gas6 mRNA expression in 49 primary breast carcinomas. Expression of PRB protein was evaluated immunohistochemically with a commercially available PRB antibody. The results showed a positive association between PRB protein and Gas6 mRNA levels (P=0.04). Gas6 correlated positively with a number of favourable prognostic variables including lymph node negativity (P=0.0002), younger age at diagnosis (P=0.04), smaller size of tumours (P=0.02), low Nottingham prognostic index scores (P=0.03) and low nuclear morphology (P=0.03). This study verifies for the first time the association between PRB and Gas6 in breast cancer tissue.

Evaluation of optimal cerebral perfusion pressure in severe traumatic brain injury

Traumatic brain injury (TBI) is a major cause of death and disability. In the 2000 guidelines, one of the suggestions for TBI treatment was to maintain cerebral perfusion pressure (CPP) < or = 70 mmHg. But in the 2003 guidelines, the suggestion was changed to < or = 60 mmHg. There have been some discrepancies of opinions about this recommendation in recent publications. In this study, we retrospectively reviewed 305 severe TBI (STBI) patients with Glasgow Coma Scales (GCS) < or = 8 between January 1, 2002 and March 31, 2003. The study group was stratified according to use or nonuse of intracranial pressure (ICP) monitoring, ICP levels, ages, and GCS levels in order to test the correlation between CCP and the prognosis. The patients < 50-year-old, with higher GCS level, with ICP monitoring, and with ICP levels < 20 mmHg had lower mortality rates and better prognosis (GOS) (p < 0.05 or 0.001). The patients in the GCS 3-5 subgroup had a significantly lower mortality and better prognosis if the CPP value was maintained higher than 70 mmHg (p < 0.05) The optimal CPP maintained < or = 60 mmHg did not fit in all STBI patients. Our study concludes that it is critical to maintain CPP substantially higher in lower GCS level patients.