Search for Subsolar-Mass Binaries in the First Half of Advanced LIGO's and Advanced Virgo's Third Observing Run

We report on a search for compact binary coalescences where at least one binary component has a mass between 0.2  M_{⊙} and 1.0  M_{⊙} in Advanced LIGO and Advanced Virgo data collected between 1 April 2019 1500 UTC and 1 October 2019 1500 UTC. We extend our previous analyses in two main ways: we include data from the Virgo detector and we allow for more unequal mass systems, with mass ratio q≥0.1. We do not report any gravitational-wave candidates. The most significant trigger has a false alarm rate of 0.14  yr^{-1}. This implies an upper limit on the merger rate of subsolar binaries in the range [220-24200]  Gpc^{-3} yr^{-1}, depending on the chirp mass of the binary. We use this upper limit to derive astrophysical constraints on two phenomenological models that could produce subsolar-mass compact objects. One is an isotropic distribution of equal-mass primordial black holes. Using this model, we find that the fraction of dark matter in primordial black holes in the mass range 0.2  M_{⊙}<m_{PBH}<1.0  M_{⊙} is f_{PBH}≡Ω_{PBH}/Ω_{DM}≲6%. This improves existing constraints on primordial black hole abundance by a factor of ∼3. The other is a dissipative dark matter model, in which fermionic dark matter can collapse and form black holes. The upper limit on the fraction of dark matter black holes depends on the minimum mass of the black holes that can be formed: the most constraining result is obtained at M_{min}=1  M_{⊙}, where f_{DBH}≡Ω_{DBH}/Ω_{DM}≲0.003%. These are the first constraints placed on dissipative dark models by subsolar-mass analyses.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Prevalence and risk factors of genitourinary Chlamydia trachomatis infection among patients attending sexually transmitted disease clinics in northern Malaysia

INTRODUCTION

Chlamydia trachomatis is one of the most common sexually transmitted diseases (STDs) globally. However, data on its prevalence and risk factors in Malaysia is still scarce.

OBJECTIVE

We aimed to identify the prevalence and risk factors of genitourinary C.trachomatis infection among patients attending STD clinics in northern Peninsular Malaysia.

METHODS

A hospital-based cross-sectional study was conducted in STD clinics of Hospital Pulau Pinang and Hospital Sultanah Bahiyah, Kedah from January to November 2014. Participants were individually interviewed using a structured data collection form followed by a physical examination and laboratory tests. Nucleic Acid Amplification Test (NAAT) was used to detect C.trachomatis infection. Analysis was carried out using SPSS Version 15.

RESULTS

Eighty-three sexually active patients were enrolled, consisting of 51 males and 32 females. The median age was 28.0 years. In general, 32.5% patients were asymptomatic, the remaining presented with genital discharge (41.0%), genital warty lesion (25.3%), genital ulcer (13.3%), dysuria (13.3%), dyspareunia (2.4%), urine hesistancy (1.2%) and genital swelling (1.2%). The prevalence of genitourinary C.trachomatis infection was 21.7% in the study population; 17.6% in males and 28.1% in females. Among the infected females, 44.4% were pregnant. Of those infected 56.6% did not show any symptoms of genital infection, and 77.8% were aged between 18 and 30 years, of which most were females. Among newly diagnosed HIV patients, the prevalence was 14.3%. From multivariable logistic regression analysis, age under 28 years, being married and engagement in oral sex had significantly increased odds of C.trachomatis infection.

CONCLUSIONS

C.trachomatis infection was common among patients attending STD clinics in northern Penisular Malaysia especially in the younger age groups. Majority of the infected patients were asymptomatic.

P2782Specific air pollution indicators are related to recurrence of ischemic stroke-a nationwide cohort study with surveillance system by time-stratified case-crossover study design

Background and objective

Ischemic stroke (IS) is the 2nd killer in Taiwan. There was no studies of air pollution indicators (API's) in nationwide database, on their relationship to IS recurrence. We aimed to analyze the IS incidences, its recurrence risk related to API's.

Methods

We used LHID 2005 (Longitudinal Health Insurance Database 2005) from National Health Institute Research Database (NHIRD), i.e. the entire original claim data of randomly sampled 1,000,000 beneficiaries in 2005. The national API surveillance database (PM2.5, PM10, CO, SO2, NO,NO2, NOx, O3) was incorporated with it. The IS incidences was computed by obtaining 1st admission for IS (ICD9–433, 434, 435), and the recurrence was on second IS within 30 days of 1st one. To minimize the confounding effect of comorbidities, we used a time-stratified case-crossover study design, proposed by Maclure (1991), for transient effects on acute events' risk; it is characterized by that each subject serves as his or her own control according to fixed individual characteristics, such as age, gender, lifestyle, socio-economic status, genetics and physiological status, etc. The API exposure was analyzed on the re-admission date (lag0), and 1 to 6 day before re-admission (lag1, lag2 ... lag6 etc.).

Results

The IS recurrence-readmission is strongly associated with SO2 peak level 5 days before (lag5 – 95% CI: 1.011–1.023, p=0.004) for patients above 20. Significant association of IS recurrence with PM2.5, SO2 O3, SO2 is noted in different patient groups.

Table 1. Basic demographics of ischemic stroke in Taiwan (2005–2013) Ischemic stroke N % Age, mean ± SD 68.94±12.8 Male 11832 58% Other forms of chronic ischemic heart disease (ICD9–414) 1496 7% Diabetes mellitus (ICD9–250) 6679 32% Essential hypertension (ICD9–401) 9038 44% Disorders of lipoid metabolism (ICD9–272) 4142 20% Heart failure (ICD9–428) 670 3% Hypertensive heart disease (ICD9–402) 2333 11%

Figure 1. Hazard Ratio of specific API's in IS (only shown with statistical significance): those left to line 1.0 with protective effect and vice versa (20–45, 46–64 and 65 above representative meaning for age range).

Conclusion

Specific API's are strongly associated with IS recurrence. We need a prospective cohort study designed on this topic.

Schisandrin B regulates lipid metabolism in subcutaneous adipocytes

Subcutaneous adipocytes in obese subjects have a lower sensitivity to catecholamine-induced lipolysis and a higher sensitivity to insulin anti-lipolytic effects compared to adipocytes in other adipose depots. Therefore, increasing lipolysis in subcutaneous adipocytes coupled with enhanced fatty acid oxidation may be an anti-obesity strategy. Schisandrin B (Sch B) is one of the most abundant active dibenzocyclooctadiene derivatives found in the fruit of Schisandra chinensis which is a commonly prescribed Chinese medicinal herb. We found that Sch B reduced glycerolipid contents in 3T3-L1 adipocytes and subcutaneous adipocytes dissected from DIO mice. Sch B also activated hormone sensitive lipase (HSL) and increased lipolysis in these adipocyte in a protein kinase A-dependent manner. Interestingly, Sch B increased fatty acid oxidation gene expressions in these adipocytes, implying an increase in fatty acid oxidation after treatment. In in vivo model, we found that Sch B increased HSL phosphorylation, reduced glycerolipid levels and increased fatty acid oxidation gene expressions in the subcutaneous adipocytes in the DIO mice. More importantly, Sch B significantly reduced the subcutaneous adipocyte sizes, subcutaneous adipose tissue mass and body weight of the mice. Our study provides scientific evidence to suggest a potential therapeutic function of Sch B or Schisandra chinensis seed containing Sch B in reducing obesity.

Cinnamon induces browning in subcutaneous adipocytes

Browning is the process of increasing the number of brite cells, which helps to increase energy expenditure and reduce obesity. Consumption of natural and non-toxic herbal extracts that possess the browning effect is an attractive anti-obesity strategy. In this study, we examined the browning effect of cinnamon extract. We found that cinnamon extract (CE) induced typical brown adipocyte multiocular phenotype in 3T3-L1 adipocytes. The treatment also increased brown adipocytes markers and reduced white adipocytes markers in the 3T3-L1 adipocytes. In ex vivo studies, we found that CE increased brown adipocytes markers in the subcutaneous adipocytes isolated from db/db mice and diet-induced obesity (DIO) mice. However, CE did not significantly affect UCP1 expression in the adipocytes isolated from perinephric adipose tissue and epididymal adipose tissue. β3-adernergic receptor (β3-AR) antagonist reduced the CE-enhanced UCP1 expression, suggesting an involvement of the β3-AR activity. Oral administration of CE significantly increased UCP1 expression in the subcutaneous adipose tissue in vivo and reduced the body weight of the DIO mice. Taken together, our data suggest that CE has a browning effect in subcutaneous adipocytes. Our study suggests a natural non-toxic herbal remedy to reduce obesity.

Metabolomics reveals the mechanisms for the cardiotoxicity of Pinelliae Rhizoma and the toxicity-reducing effect of processing

Pinelliae Rhizoma (PR) is a commonly used Chinese medicinal herb, but it has been frequently reported about its toxicity. According to the traditional Chinese medicine theory, processing can reduce the toxicity of the herbs. Here, we aim to determine if processing reduces the toxicity of raw PR, and to explore the underlying mechanisms of raw PR-induced toxicities and the toxicity-reducing effect of processing. Biochemical and histopathological approaches were used to evaluate the toxicities of raw and processed PR. Rat serum metabolites were analyzed by LC-TOF-MS. Ingenuity pathway analysis of the metabolomics data highlighted the biological pathways and network functions involved in raw PR-induced toxicities and the toxicity-reducing effect of processing, which were verified by molecular approaches. Results showed that raw PR caused cardiotoxicity, and processing reduced the toxicity. Inhibition of mTOR signaling and activation of the TGF-β pathway contributed to raw PR-induced cardiotoxicity, and free radical scavenging might be responsible for the toxicity-reducing effect of processing. Our data shed new light on the mechanisms of raw PR-induced cardiotoxicity and the toxicity-reducing effect of processing. This study provides scientific justifications for the traditional processing theory of PR, and should help in optimizing the processing protocol and clinical combinational application of PR.

Influence of sulfur fumigation on glycoside profile in Platycodonis Radix (Jiegeng)

BACKGROUND

Over recent decades, sulfur fumigation is becoming abused in processing some freshly harvested herbs used as both medicine and food, although it has been questioned whether sulfur fumigation will change the efficacy and safety of the herbs. One of the herbs commonly processed by sulfur fumigation is Platycodonis Radix (Jiegeng in Chinese). Glycosides are the main bioactive components of Jiegeng. Up to the present, no study has been carried out to evaluate the impact of sulfur fumigation on glycoside profile of Jiegeng.

METHODS

A rapid and versatile ultra-high performance liquid chromatography coupled with ultra-high resolution quadrupole time-of-flight mass spectrometry (UHPLC UHD Q-TOF MS/MS) method was developed for comprehensive analysis of the glycoside profiles of sulfur-fumigated and air-dried Jiegeng samples.

RESULTS

Twenty-three glycosides were detected in air-dried and sulfur-fumigated Jiegeng samples. After sulfur fumigation, the peak heights of eight glycosides, namely platycogenin A, platycodin D, platycodin D2, platycodin D3, polygalacin D, polygalacin D2, deapio-platycodin D and 3″-O-acetylplatycodin D2, remarkably decreased; while peak heights of five glycosides, namely syringin, lobetyolin, platycoside E, deapio-platycodin D2 and deapio-platycoside E, slightly increased; in addition, peaks of ten glycosides, platycodin A, platycodin C, platycodin V, platycoside C, 16-oxoplatycodin D, 2″-O-acetylpolygalacin D, 2″-O-acetylpolygalacin D2, 3″-O-acetylpolygalacin D, 3″-O-acetylpolygalacin D2, and platycogenic acid B, disappeared.

CONCLUSION

Sulfur fumigation caused significant changes of glycoside components of Jiegeng. Further investigations are warranted to explore how these chemical changes occurred and whether these changes would affect the efficacy and safety of Jiegeng.

A systematic review of the literature on the surgical management of recurrent rectal prolapse

AIM

There are no available guidelines to support surgical decision-making in recurrent rectal prolapse. This systematic review evaluated the results of abdominal or perineal surgery for recurrent rectal prolapse, with the aim of developing an evidence-based treatment algorithm.

METHOD

PubMed and MEDLINE databases were searched for all clinical studies involving patients who underwent surgery for recurrent rectal prolapse between 1950 and 2014. The primary outcome measure was the recurrence rate after abdominal or perineal surgery for recurrent rectal prolapse. Secondary outcomes included morbidity, mortality and quality of life data where available.

RESULTS

There were no randomized controlled studies comparing the success rates of abdominal or perineal surgery for recurrent rectal prolapse. Most studies were heterogeneous, of low quality (level IV) and involved small numbers of patients. The follow-up of 144 patients included in the studies undergoing perineal surgery ranged from 8.8 to 81 months, with recurrence rates varying from 0% to 50%. Morbidity ranged from 0% to 17% with no mortality reported. Limited data on quality of life following the Altemeier procedure were available. The follow-up for 158 patients included in the studies who underwent abdominal surgery ranged from 0 to 23 years, during which recurrence rates varied from 0% to 15%. Morbidity rates ranged from 0% to 32% with 4% mortality. No quality of life data were available for patients undergoing abdominal surgery.

CONCLUSION

This systematic review was unable to develop a treatment algorithm for recurrent rectal prolapse due to the variety of surgical techniques described and the low level of evidence within heterogeneous studies. Larger high-quality studies are necessary to guide practice in this difficult area.

Lipidomic-based investigation into the regulatory effect of Schisandrin B on palmitic acid level in non-alcoholic steatotic livers

Schisandrin B (SchB) is one of the most abundant bioactive dibenzocyclooctadiene derivatives found in the fruit of Schisandra chinensis. Here, we investigated the potential therapeutic effects of SchB on non-alcoholic fatty-liver disease (NAFLD). In lipidomic study, ingenuity pathway analysis highlighted palmitate biosynthesis metabolic pathway in the liver samples of SchB-treated high-fat-diet-fed mice. Further experiments showed that the SchB treatment reduced expression and activity of fatty acid synthase, expressions of hepatic mature sterol regulatory element binding protein-1 and tumor necrosis factor-α, and hepatic level of palmitic acid which is known to promote progression of steatosis to steatohepatitis. Furthermore, the treatment also reduced hepatic fibrosis, activated nuclear factor-erythroid-2-related factor-2 which is known to attenuate the progression of NASH-related fibrosis. Interestingly, in fasting mice, a single high-dose SchB induced transient lipolysis and increased the expressions of adipose triglyceride lipase and phospho-hormone sensitive lipase. The treatment also increased plasma cholesterol levels and 3-hydroxy-3-methylglutaryl-CoA reductase activity, reduced the hepatic low-density-lipoprotein receptor expression in these mice. Our data not only suggest SchB is a potential therapeutic agent for NAFLD, but also provided important information for a safe consumption of SchB because SchB overdosed under fasting condition will have adverse effects on lipid metabolism.

A case-controlled pilot study assessing the safety and efficacy of the Stapled Mesh stomA Reinforcement Technique (SMART) in reducing the incidence of parastomal herniation

BACKGROUND

Parastomal hernias (PH) are frequent with a high morbidity. Three randomised controlled trials have shown that prophylactic mesh stoma reinforcement significantly reduces their incidence. Implantation and fixation of mesh can be time-consuming, difficult to perform laparoscopically and does not deal with the excessive stretching of the trephine and the creation of an oversized defect. The Stapled Mesh stomA Reinforcement Technique (SMART) obviates these technical problems. The aim of this study was to assess the safety and efficacy of a novel surgical technique called SMART in preventing parastomal herniation.

METHOD

SMART uses a purpose designed circular stapling gun (Compact™, Frankenman International Limited) of various diameters to create a precise trephine and simultaneously fixes a mesh sub-peritoneally and circumferentially to the trephine. Recruited patients were deemed to be high risk for parastomal herniation and randomisation in a controlled trial was contraindicated. Incidence of parastomal related symptoms and recurrences were documented at clinic visits and radiological confirmation of recurrences, when available, was used for final analysis. A control group of patients who underwent stoma resiting without mesh reinforcement for parastomal herniation was used for comparative purposes.

RESULTS

22 patients (16 F:6 M, mean age 49 ± 16 years, BMI 33.0 ± 7.0) underwent SMART (18 open, 4 laparoscopic). There were no intra-operative or early stoma complications. During a median FU of 21 months (range 12-24), four patients (19%) were diagnosed with recurrent parastomal herniation, one of which required re-operation. The parastomal herniation rate (73%) in the control group (6 F:5 M) was significantly higher (p = 0.003) although patients had similar age (59 ± 15 years, p = 0.1) and body-mass index (29.0 ± 3.0, p = 0.1).

CONCLUSION

SMART is a new and simple technique of precisely creating a reinforced stoma trephine at both open and laparoscopic surgery. It obviates the technical disadvantages of traditional stoma formation. This pilot study, in a selected group of patients at high risk for parastomal herniation, indicates that the procedure is clinically safe but randomised controlled trials are required to determine its efficacy in reducing parastomal herniation in all patients undergoing elective stoma formation.

Gracilis muscle interposition for rectovaginal and anovaginal fistula repair: a systematic literature review

BACKGROUND

Repair of rectovaginal fistula (RVF) is associated with high recurrence. For this reason gracilis muscle interposition is increasingly being used.

AIM

To evaluate the efficacy of this procedure for RVF repair.

METHOD/SEARCH STRATEGY

A search of PubMed and Medline databases was performed in November 2013 using the text terms and MESH headings 'rectovaginal fistula/fistulation', and 'gracilis muscle', spanning 1980-2013. The search strategy was restricted to articles written in English with available abstracts. Sample size, aetiology of RVF, previous repair attempts, follow-up period, healing rates and complications were recorded and analysed.

RESULTS

Seventeen studies involving 106 patients were analysed. The cause of RVF included inflammatory bowel disease (n = 37 [34.9%]: Crohn's disease [34], ulcerative colitis [3]), pelvic surgery (37 [34.9%]), obstetric injury (9 [8.5%]), malignancy (7 [6.6%]), trauma (5 [4.7%]), miscellaneous (idiopathic, endometriosis, radiation: 11 [10.4%]). Patients had undergone a median number of two previous unsuccessful repairs. At a median follow-up of 21 months, healing had occurred in 33-100% (median 100%) with the largest studies reporting rates between 60% and 90%. Thirteen studies did not report any complications, with the remainder reporting only minor morbidity.

CONCLUSION

Gracilis interposition appears to have a reasonable success rate for RVF repair with acceptable morbidity. It may be considered as one of the first-line treatment options for recurrent RVF.

Subcutaneous adipocytes promote melanoma cell growth by activating the Akt signaling pathway: role of palmitic acid

Tumorigenesis involves constant communication between tumor cells and neighboring normal cells such as adipocytes. The canonical function of adipocytes is to store triglyceride and release fatty acids for other tissues. This study was aimed to find out if adipocytes promoted melanoma cell growth and to investigate the underlying mechanism. Here we isolated adipocytes from inguinal adipose tissue in mice and co-cultured with melanoma cells. We found that the co-cultured melanoma had higher lipid accumulation compared with mono-cultured melanoma. In addition, fluorescently labeled fatty acid BODIPY® FLC16 signal was detected in melanoma co-cultured with the adipocytes that had been loaded with the fluorescent dye, suggesting that the adipocytes provide fatty acids to melanoma cells. Compared with mono-cultured melanoma, co-cultured melanoma cells had a higher proliferation and phospho-Akt (Ser-473 and Thr-450) expression. Overexpression of Akt mutants in melanoma cells reduced the co-culture-enhanced proliferation. A lipidomic study showed that the co-cultured melanoma had an elevated palmitic acid level. Interestingly, we found that palmitic acid stimulated melanoma cell proliferation, changed the cell cycle distribution, and increased phospho-Akt (Ser-473 and Thr-450) and PI3K but not phospho-PTEN (phosphophosphatase and tensin homolog) expressions. More importantly, the palmitic acid-stimulated proliferation was further enhanced in the Akt-overexpressed melanoma cells and was reduced by LY294002 or knockdown of endogenous Akt or overexpression of Akt mutants. We also found that palmitic acid-pretreated B16F10 cells were grown to a significantly larger tumor in mice compared with control cells. Taken together, we suggest that adipocytes may serve as an exogenous source of palmitic acid that promotes melanoma cell growth by activating Akt.

UHPLC UHD Q-TOF MS/MS analysis of the impact of sulfur fumigation on the chemical profile of Codonopsis Radix (Dangshen)

Over recent decades sulfur fumigation has been becoming abused in processing some freshly harvested Chinese medicinal herbs, although it is questioned whether sulfur fumigation can result in changes in efficacy and safety of the herbs. One of the herbs commonly processed by sulfur fumigation is Codonopsis Radix (Dangshen). A report showed that lobetyolin content in sulfur-fumigated Dangshen was lower than in air-dried Dangshen. Whereas there is no investigation designed to compare the chemical profiles of the sulfur-fumigated Dangshen and the air-dried Dangshen. In the present study, a rapid and versatile ultra-high-performance liquid chromatography coupled with ultra-high resolution quadrupole time-of-flight mass spectrometry (UHPLC UHD Q-TOF MS/MS) method was developed for comprehensive analysis of the chemical profiles of sulfur-fumigated and air-dried Dangshen samples. Principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) demonstrated that there were significant chemical differences between sulfur-fumigated and air-dried Dangshen samples. Among the changed components, 57 compounds were identified, in which 15 sulfur-containing compounds were detected only in sulfur-fumigated samples. The established methods were successfully applied to discriminate sulfur-fumigated Dangshen among commercial samples. Whether the chemical changes caused by sulfur fumigation affect the clinical efficacy and safety of Dangshen needs to be further investigated.

A cellular lipidomic study on the Aβ-induced neurotoxicity and neuroprotective effects of EGCG by using UPLC/MS-based glycerolipids profiling and multivariate analysis

The aim of this study was to investigate the cellular lipid metabolism associated with β-amyloid peptide (Aβ)-induced neurotoxicity as well as the neuroprotective effect of (-)-epigallocatechin gallate (EGCG), a major polyphenol in green tea. An ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS)-based lipidomic approach was developed to screen and identify changes of the glycerolipids (GL) upon Aβ treatment with or without the presence of EGCG in PC12 cells. Principle component analysis (PCA) showed that the Aβ-treated group was well separated from the control group, whereas the EGCG group was closer to the control group. The GL levels were significantly elevated in Aβ-treated cells compared with the control group, but were restored near to normal levels after EGCG treatment. The elevated phosphatidylcholines (PCs) levels observed in the Aβ-treated PC12 cells were quite probably the integrated results of the reduced phospholipase A(2) (PLA(2)) activity and the enhanced activity of lysophospholipid acyltransferases. Moreover, an increased liberation of arachidonic acid (AA) from PCs was observed as another important response of PC12 cells to the Aβ aggregates, implying an active inflammatory process occurring in Aβ induced neurotoxicity. EGCG treatment can reverse the deregulated metabolism of PCs, which might be one of the biochemical mechanisms contributing to its neuroprotective effect. Collectively, results obtained from the current lipidomic analyses of PC12 cells provided important insight into the biochemical mechanisms underlying Aβ-induced neurotoxicity and neuro protective effects of EGCG. This is the first report of the lipidomic study on the neuroprotective effect of EGCG.

The persistent challenge of parastomal herniation: a review of the literature and future developments

AIM

The aim of this review article was to outline current evidence relating to the treatment and prevention of parastomal herniation with a view to guide surgeons dealing with patients potentially affected by this complication.

METHOD

Medline and PubMed databases were searched using the keywords 'parastomal hernia/herniation', 'stoma hernia/herniation' and 'stoma complications'. Evidence was obtained from randomized and non-randomized studies. Case reports and articles not written in English were excluded. Qualitative assessment of all included studies was performed using the Oxford Centre for Evidence-Based Medicine 2011 levels of evidence.

RESULTS

The search revealed a total of 228 publications of which 115 fulfilled the selection criteria. Stoma formation through the rectus muscle is complicated by parastomal herniation in up to 50% of cases. There is no conclusive evidence that alternative techniques (e.g. extraperitoneal, lateral rectus abdominis positioned stoma) are superior. Open and laparoscopic parastomal hernia repair have similar recurrence rates up to 50%. The 'Sugarbaker' technique appears to be superior to the 'keyhole' technique when a laparoscopic approach is used. Prophylactic mesh reinforcement of the stoma trephine appears to reduce the herniation rate to approximately 15% and is accompanied by a decrease in symptomatic hernias requiring repair without any difference in stoma-related morbidity.

CONCLUSION

Large prospective controlled trials are required to compare surgical techniques of stoma formation in reducing the incidence of parastomal herniation. Despite limited evidence, routine prophylactic mesh reinforcement of the stoma trephine should be offered to all patients undergoing permanent stoma formation.

Lipidomics identification of metabolic biomarkers in chemically induced hypertriglyceridemic mice

In this study, we aim to identify the potential biomarkers in hTG pathogenesis in schisandrin B-induced hTG mouse model. To investigate whether these identified biomarkers are only specific to schisandrin B-induced hTG mouse model, we also measured these biomarkers in a high fat diet (HFD)-induced hTG mouse model. We employed a LC/MS/MS-based lipidomic approach for the study. Mouse liver and serum metabolites were separated by reversed phase liquid chromatography. Metabolite candidates were identified by matching with marker retention times, isotope distribution patterns, and high-resolution MS/MS fragmentation patterns. Subsequently, target candidates were quantified by quantitative MS. In the schisandrin B-induced hTG mice, we found that the plasma fatty acids, diglyceroids, and phospholipids were significantly increased. Palmitic acid and stearic acid were increased in the plasma; oleic acid, linoleic acid, linolenic acid, arachidonic acid, and docosahexaenoic acid were increased in both the plasma and the liver. Acetyl-CoA, malonyl-CoA, and succinyl-CoA were increased only in the liver. The changes in levels of these identified markers were also observed in HFD-induced hTG mouse model. The consistent results obtained from both hTG models not only suggest novel biomarkers in hTG pathogenesis, but they also provide insight into the underlying mechanism of the schisandrin B-induced hTG.

Formation of hydrides in (Ti(1-x)Zr(x))Co(2.00) (0 < x < 1) pseudobinary alloys

The exposure of (Ti(1-x)Zr(x))Co(2.00) intermetallic alloys to hydrogen at high pressure caused (Ti(1-x)Zr(x))Co(2.00) (x = 0.50-0.90) hydrides in the alloy. The crystalline structural, electronic, and magnetic properties of parent alloys and of their hydrides were determined by using XRD (X-ray powder diffraction) and XAS (X-ray absorption spectrometry) and by the use of SQUID (a superconducting quantum interference device). Hydrogenation did not alter the crystal structure of the parent alloy, but it did increase the volume of the unit cell. An in situ Co K-edge XAS study of the hydride revealed that the valence state of Co increased during discharge (which is the release of hydrogen from the hydride). Hydrogenation of the parent alloy also reduced the magnetic moment. A possible mechanism of discharge for the hydride is also proposed.