Publications by authors named "Loh J"

Introduction: Incisional hernias are among the most frequent complications in visceral surgery and are currently considered to be an indication for surgery in all cases, regardless of the patient's symptoms. However, it still remains unclear to what extent surgery actually results in improvement according to objective (e.g.

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Racial residential segregation is associated with health inequalities in the USA, and one of the primary mechanisms is through influencing features of the neighborhood physical environment. To better understand how Black residential segregation might contribute to health risk, we examined retail redlining; the inequitable distribution of retail resources across racially distinct areas. A combination of visual and analytic methods was used to investigate whether predominantly Black census block groups in New York City had poor access to retail stores important for health.

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Helicobacter pylori infection and consumption of a high-salt diet are each associated with an increased risk for the development of gastric cancer. To investigate potential synergism between these factors, we used a global proteomic approach to analyze H. pylori strains cultured in media containing varying salt concentrations.

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Transforming growth factor (TGF) β1 may be a candidate for a serologic tumor marker. In this study, the plasma levels of TGF-β1 in patients with brain tumors were measured using enzyme-linked immunosorbent assay before and after tumor removal. Patients were divided into four groups, the control group and the benign, malignant, and metastatic brain tumor groups.

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Published toxicology data on chitosan nanoparticles (NP) often lack direct correlation to the in situ size and surface characteristics of the nanoparticles, and the repeated NP assaults as experienced in chronic use. The aim of this paper was to breach these gaps. Chitosan nanoparticles synthesized by spinning disc processing were characterised for size and zeta potential in HBSS and EMEM at pHs 6.

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Whilst studies have shown that antimicrobial stewardship programmes (ASPs) can effectively reduce antibiotic utilisation, cost of care and even antimicrobial resistance rates, ASPs should avoid the perception that the goal is primarily to reduce antibiotic purchases and costs, instead of focusing on improving the quality of care. In addition, to address the concern of primary physicians who deemed that ASPs' choices of antibiotics were often inadequate, the impact of ASPs on patient safety should be monitored and evaluated. The aim of this study was to analyse the impact of ASP interventions on patient safety in Singapore General Hospital (SGH), a 1559-bed, large, acute, tertiary-care hospital in Singapore.

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Background: Thoracic multidisciplinary meetings (TMDM) are a key component of lung cancer patient management. The optimal design, organisation and function of TMDM are uncertain, and different models may serve different purposes. In the Auckland/Northland region, there are two contemporaneous weekly TMDM using different formats; one is a co-located TMDM (C-TMDM), and the other is a video conference TMDM (V-TMDM) connecting different locations.

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Introduction: Norovirus gastrointestinal disease (GID) outbreaks occur frequently in closed settings, with high attack rates. On October 16, 2008, a norovirus GID outbreak occurred at a Singapore military camp. This study describes the epidemiological investigations conducted to determine the cause of outbreak and the efficacy of the public health measures implemented.

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Background: Helicobacter pylori infection is usually acquired in childhood, but little is known about its natural history in asymptomatic children, primarily due to the paucity of non-invasive diagnostic methods. H. pylori strains harboring cagA and specific alleles of hopQ and vacA are associated with increased risk for gastric cancer.

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Viral immune invasion proteins are highly effective probes for studying physiological pathways. We report here the characterization of a new viral ubiquitin ligase pK3 expressed by rodent herpesvirus Peru (RHVP) that establishes acute and latent infection in laboratory mice. Our findings show that pK3 binds directly and specifically to class I major histocompatibility proteins (MHCI) in a transmembrane-dependent manner.

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Streptococcal mitogenic exotoxin Z-2 (SMEZ-2) is a streptococcal superantigen that primarily stimulates human T cells bearing Vβ8 and mouse T cells bearing Vβ11. Mutagenesis of T cell receptor (TCR)-binding residues (W75L, K182Q, D42C) produced a mutant called M1 that was >10(5)-fold less active toward human peripheral blood lymphocytes and splenocytes from transgenic mice that express human CD4 and either human HLA-DR3-DQ2 or HLA-DR4-DQ8. Similarly, cytokine production in response to M1 in lymphocyte culture was rendered undetectable, and no change in the frequency of Vβ11-bearing T cells in mice receiving M1 was observed.

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Background: Influenza infections may result in different clinical presentations. This study aims to determine the clinical differences between circulating influenza strains in a young healthy adult population in the tropics.

Methods: A febrile respiratory illness (FRI) (fever ≥ 37.

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BCL2L12 has been reported to be involved in post-mitochondrial apoptotic events in glioblastoma, but the role of BCL2L12A, a splicing variant of BCL2L12, remains unknown. In this study, we showed that BCL2L12 and BCL2L12A were overexpressed in glioblastoma multiforme (GBM). Large-scale yeast two-hybrid screening showed that BCL2L12 was a GSK3b binding partner in a testis cDNA library.

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Exercise has beneficial effects on human health, including protection against metabolic disorders such as diabetes. However, the cellular mechanisms underlying these effects are incompletely understood. The lysosomal degradation pathway, autophagy, is an intracellular recycling system that functions during basal conditions in organelle and protein quality control.

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AQP4 water channels are thought to be the target of autoimmune attack in neuromyelitis optica-spectrum disorders (NMOsd). AQP4 are highly expressed on ventricular ependyma. The objective of this study was to describe a novel pattern of linear, 'pencil-thin' enhancement of ventricular ependyma in NMOsd.

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In the elderly, immunosenescence and malnourishment can contribute to increased risk and severity of upper respiratory tract infections (URTI). Gold kiwifruit (Actinidia chinensis 'Hort16A') contains nutrients important for immune function and mitigation of symptoms of infection, including vitamins C and E, folate, polyphenols and carotenoids. The objective of the present study was to evaluate whether regular consumption of gold kiwifruit reduces symptoms of URTI in older people, and determine the effect it has on plasma antioxidants, and markers of oxidative stress, inflammation and immune function.

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Herpesviruses are thought to be highly genetically stable, and their use as vaccine vectors has been proposed. However, studies of the human gammaherpesvirus, Epstein-Barr virus, have found viral isolates containing mutations in HLA class I-restricted epitopes. Using murine gammaherpesvirus 68 expressing ovalbumin (OVA), we examined the stability of a gammaherpesvirus antigenic locus under strong CD8 T cell selection in vivo.

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Background: Limited information is available about pandemic H1N1-2009 influenza vaccine effectiveness in tropical communities. We studied the effectiveness of a pandemic H1N1 vaccination program in reducing influenza cases in Singapore.

Methods: A surveillance study was conducted among military personnel presenting with febrile respiratory illness from mid-2009 to mid-2010.

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Cerebral vasospasm following subarachnoid hemorrhage (SAH) has been studied in terms of a contraction of the major cerebral arteries, but the effect of cerebrum tissue in SAH is not yet well understood. To gain insight into the biology of SAH-expressing cerebrum, we employed oligonucleotide microarrays to characterize the gene expression profiles of cerebrum tissue at the early stage of SAH. Functional gene expression in the cerebrum was analyzed 2 h following stage 1-hemorrhage in Sprague-Dawley rats.

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Colonization of the human stomach by Helicobacter pylori is an important risk factor for development of gastric cancer. The H. pylori cag pathogenicity island (cag PAI) encodes components of a type IV secretion system (T4SS) that translocates the bacterial oncoprotein CagA into gastric epithelial cells, and CagL is a specialized component of the cag T4SS that binds the host receptor α5β1 integrin.

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Inappropriate antibiotic use contributes to antimicrobial resistance. Multi-faceted antimicrobial stewardship programmes (ASPs) are recommended for sustainable changes in prescribing practices. A multi-disciplinary ASP was established in October 2008 and piloted in the Departments of General Surgery, Renal Medicine and Endocrinology sequentially.

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A reaction pairing strategy centered on utilization of a reaction triad (sulfonylation, S(N)Ar addition and Mitsunobu alkylation) generating skeletally diverse, tricyclic and bicyclic benzofused sultams is reported. Pairing sulfonylation and S(N)Ar reactions yields bridged, tricyclic and bicyclic benzofused sultams. Application of the Mitsunobu reaction in a sulfonylation-Mitsunobu-S(N)Ar pairing allows access to benzthiazocine-1,1-dioxides, while a simple change in the order of pairing to sulfonylation-S(N)Ar-Mitsunobu affords structurally different, bridged tricyclic benzofused sultams.

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Background: Helicobacter pylori infection is a risk factor for the development of gastric cancer, and the bacterial oncoprotein CagA contributes to gastric carcinogenesis.

Methods: We analyzed H. pylori isolates from persons in Colombia and observed that there was marked variation among strains in levels of CagA expression.

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Several studies have demonstrated that anti-Müllerian hormone (AMH) is a better marker of ovarian reserve than age, basal FSH, estradiol and inhibin. AMH is very good in (i) predicting both over- and poor-response in the controlled ovarian stimulation environment, (ii) determining the most appropriate stimulation regimen and (iii) pre-treatment counselling for couples to make an appropriate and informed choice. Recent reports are exploring the use of AMH in various other indications, including (i) predicting long-term fertility and guiding how long a woman can delay childbearing without facing the risk of reduced ovarian reserve, (ii) predicting the age of menopause, (iii) prediction of ovarian ageing in women prior to or following chemotherapy, (iv) prediction of long-term fertility following ovarian surgery and (v) screening for polycystic ovaries.

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