Characterisation of admissions and readmissions after 20 days of illness among COVID-19 patients

INTRODUCTION

There has been an observed number of readmissions after an index COVID-19 admission, including admissions after an initial home quarantine. The purpose of this study was to identify the clinical characteristics and outcomes of COVID-19 patients who were readmitted or admitted after an initial home quarantine between 21 and 90 days of illness.

MATERIALS AND METHODS

This was a single-centre retrospective cohort study comprising patients admitted to a state hospital in Selangor, Malaysia, between August and October 2021. The demographic data, clinical characteristics, presenting complaints, laboratory tests, organ dysfunction, use of invasive ventilation, intensive care unit (ICU) admissions, length of hospitalisation and mortality were collected and analysed.

RESULTS

The analysis involved a total of 195 cases. More than a quarter of the cases (52 [26.7%]) were related to the initial COVID-19 infection. Nine cases (4.6%) required mechanical ventilation, while eight cases (4.1%) were admitted to the ICU. The overall mortality was 17 cases (8.7%). Surviving patients were younger (49.5 vs. 58.4 years), less likely to have diabetes mellitus (48.3% vs. 82.4%), or chronic kidney disease (12.9% vs. 41.2%); had higher levels of admission haemoglobin (12.6 vs. 9.1g/dL) and albumin (33.0 vs. 21.0g/L); lower white blood cells (10.2 vs. 13.0 × 109/L), creatinine (81.2 vs. 151.9μmol/L) and C-reactive protein (18.2 vs. 135.0mg/L) at admission; less likely to have MI (6.7% vs. 23.5%), sepsis (3.4% vs. 47.1%), or acute kidney injury (3.4% vs. 17.6%) and organ dysfunction (25.3% vs. 94.1%).

CONCLUSION

Approximately a quarter of patients were admitted or readmitted due to direct COVID-19 complications between 21 and 90 days of illness. The baseline oxygen requirements at admission were independently associated with mortality, invasive mechanical ventilation and ICU admissions. Further research is needed to establish a risk model for patients returning to a hospital to predict their risk of post-COVID complications.

First molecular detection of porcine circovirus type 4 (PCV4) in Malaysia

Porcine circovirus type 4 (PCV4) is the newest member in the porcine circovirus family, first reported in 2020. To date, the presence of PCV4 has only been reported in China, South Korea and most recently in Thailand. Detection of PCV4 have been reported in various production stages of pigs from piglets, finishers to sows; associated with a myriad of clinical manifestations including porcine dermatitis and nephropathy syndrome (PDNS), postweaning multisystemic wasting syndrome (PMWS), respiratory, enteric and neurological diseases. While successful virus isolation and culture has yet to be reported, pathogenicity of PCV4 has been demonstrated through infectious clone studies. The objective of this study is to investigate the presence of PCV4 in Malaysian porcine population to update the epidemiology of porcine circoviruses in Malaysia. A total of 49 samples from commercial intensive pig farms, abattoir and wild boar population were subjected to conventional polymerase chain reaction assay to detect PCV4 capsid (cap) genome. Resulting cap nucleotide sequences were analyzed for maximum likelihood phylogeny relationship. Results revealed that PCV4 is present in Peninsular Malaysia at a molecular prevalence of 4.08% (2 / 49 samples). Both PCV4 positive samples originated from clinically healthy finishers. Malaysian PCV4 strains were classified as genotype PCV4b, and were found to be phylogenetically distinct from the China, South Korea and Thailand strains. With this latest update of the novel PCV4 in Malaysia, it is clear that more attention needs to be given to the investigation of novel porcine circoviruses (PCV) and management of PCV diseases.

Prominent corneal nerves in pure mucosal neuroma syndrome, a clinical phenotype distinct from multiple endocrine neoplasia type 2B

BACKGROUND

Pure mucosal neuroma syndrome (MNS), an autosomal dominant neurocutaneous disorder, is a rare discrete subgroup in multiple endocrine neoplasia (MEN) type 2B, which present without associated endocrinopathies of MEN2B but with typical physical features such as prominent corneal nerves. Case presentation This report describes a 41-year-old patient with complaint of itchy eyes and irritation, presenting with blocked gland orifices in the upper and lower eyelids, light conjunctival hyperemia, a semitransparent neoplasm measuring 2 mm*2 mm on the nasal limbus suggestive of neuromas, and prominent corneal nerves. In vivo confocal microscopy (IVCM) revealed structural alterations-namely a prominent hyperreflective, thickened nerve plexus and a normal endothelium-in both eyes. Testing for SOS1 mutation was positive. This patient may represent a discrete subgroup termed pure mucosal neuroma syndrome (MNS), which presents with the characteristic appearance of MEN2B but without RET gene mutations.

CONCLUSION

Prominent corneal nerves have been described in some diseases, such as multiple endocrine neoplasia (MEN) type 1 and type 2A and 2B, congenital ichthyosis, Refsum's disease, leprosy, etc. Ophthalmic assessment including prominent corneal nerves has proven valuable in asymptomatic individuals of MEN2B. Our case illustrates the importance of recognizing the ocular features of MNS, a rare presentation of MEN2B, in order to prevent prophylactic thyroidectomy in these patients for prophylactic thyroidectomy is not mandatory in MNS. However, regular monitoring and genetic counseling are still necessary.

Association of dengue serotypes and its complications: a retrospective cohort study

INTRODUCTION

Dengue fever is an arthropod-borne disease and has a wide clinical spectrum. It is hypothesised that dengue serotypes could be a possible factor for such phenomena and therefore be a possible predictor for the development of severe dengue.

METHOD

A retrospective cohort study was done to explore the association between dengue serotypes and the various complications. All patients who underwent dengue serotyping from 1st January to 31st December 2018 in Tengku Ampuan Rahimah Hospital were selected. Serotypes were randomly done for admitted dengue patients. Notes were then retrieved for data collection. Secondary outcomes like length of stay and highest lactate level were also studied. Data analysis was done using SPSS version 20.

RESULT

A total of 193 patient records were included in the analysis. Chi-square test for independence indicated that the proportion of dengue complications between male and female were significantly different (χ²(1) = 11.37, p = 0.001). Dengue serotype was not associated with the development of dengue complications, total number of dengue complications, length of admission, lactate level and survival among the serotypes. Results of the binary logistic regression showed that men have thrice the odds (AOR = 3.3, 95% CI: 1.6 6.7) for developing dengue complications. One patient was found to be co-infected with serotype 2 and 3.

CONCLUSION

Our study did not reveal any association between the different dengue virus serotypes and its complications. Therefore, all dengue infection should be approached with equal meticulousness. There are possibilities that apart from serotype, dengue genotype and lineage would determine clinical outcome. However, more studies are required to study such associations.

3D Printing and Performance Study of Porous Artificial Bone Based on HA-ZrO2-PVA Composites

An ideal artificial bone implant should have similar mechanical properties and biocompatibility to natural bone, as well as an internal structure that facilitates stomatal penetration. In this work, 3D printing was used to fabricate and investigate artificial bone composites based on HA-ZrO₂-PVA. The composites were proportionally configured using zirconia (ZrO₂), hydroxyapatite (HA) and polyvinyl alcohol (PVA), where the ZrO₂ played a toughening role and PVA solution served as a binder. In order to obtain the optimal 3D printing process parameters for the composites, a theoretical model of the extrusion process of the composites was first established, followed by the optimization of various parameters including the spray head internal diameter, extrusion pressure, extrusion speed, and extrusion line width. The results showed that, at the optimum parameters of a spray head diameter of 0.2 mm, extrusion pressure values ranging from 1-3 bar, a line spacing of 0.8-1.5 mm, and a spray head displacement range of 8-10 mm/s, a better structure of biological bone scaffolds could be obtained. The mechanical tests performed on the scaffolds showed that the elastic modulus of the artificial bone scaffolds reached about 174 MPa, which fulfilled the biomechanical requirements of human bone. According to scanning electron microscope observation of the scaffold sample, the porosity of the scaffold sample was close to 65%, which can well promote the growth of chondrocytes and angiogenesis. In addition, c5.18 chondrocytes were used to verify the biocompatibility of the composite materials, and the cell proliferation was increased by 100% when compared with that of the control group. The results showed that the composite has good biocompatibility.

Creep Behavior of A356 Aluminum Alloy Reinforced with Multi-Walled Carbon Nanotubes by Stir Casting

Lightweight aluminum alloy components are often used to manufacture a variety of engineering components in many industries. In recent years, researchers have studied the effect of improving the mechanical properties of metal alloys by incorporating nano-carbon into its structure. In this study, the effect of the addition of 0.2, 0.5, and 1 wt% of multi-walled carbon nanotubes (MWCNTs) on the stress-strain behavior and creep phenomenon of an A356 aluminum alloy were studied. The effect of nickel coating on 0.2 wt% MWCNTs was also investigated. Samples were prepared using the stir-casting method. The results revealed that the grain size became finer when MWCNT nano-particulates were introduced. Although the MWCNTs were distributed homogeneously in the A356 matrix, as confirmed by FESEM analysis, there were some agglomerations observed in a specific area with dimensions smaller than 100 nm. Nevertheless, the addition of MWCNTs was found to be beneficial in enhancing the hardness of alloys containing 0.2 wt%, 0.2 wt% nickel-coated, 0.5 wt%, and 1 wt% MWCNTs by 9%, 24%, 32%, and 15%, respectively, as compared with the unreinforced A345 matrix. It was also found that the 0.5 wt% MWCNT-A356 matrix exhibited an improvement in the creep lifetime by more than two orders of magnitude.

Tissue factor cytoplasmic domain exacerbates post-infarct left ventricular remodeling via orchestrating cardiac inflammation and angiogenesis

Introduction

The coagulation protein tissue factor (TF) regulates inflammation and angiogenesis via its cytoplasmic domain in infection, cancer and diabetes. While TF is highly abundant in the heart and implicated in cardiac injuries and dysfunction, the contribution of its cytoplasmic domain in cardiac pathology remains unclear.

Purpose

We aimed to investigate the contribution of the cytoplasmic domain of TF to post-infarct myocardial injury and adverse left ventricular (LV) remodeling.

Methods and results

Myocardial infarction was induced by permanent occlusion of the left anterior descending coronary artery. Male mice with C57BL/Jax background were used for the study. Compared with wild-type mice, mice lacking the TF cytoplasmic domain (TFΔCT) had a higher survival rate (90.5% versus 70%, p=0.0298) during a 28-day follow-up after myocardial infarction. Among surviving mice, TFΔCT mice had better cardiac function and less LV remodeling (ESV: 114.5±13.1mL for WT, 67.06±10.8mL for TFΔCT, p<0.001; EDV: 146.6±12.4mL for WT, 99.97±11.71mL for TFΔCT, p<0.001) than wild-type mice. Bone marrow chimerism indicated that deletion of the TF cytoplasmic domain in either bone marrow-derived cells or cardiac resident cells could alleviate post-infarct cardiac dysfunction. Speckle-tracking strain analysis revealed that the overall improvement of post-infarct cardiac performance in TFΔCT mice was attributed to reduced myocardial deformation in the peri-infarct region (strain-%: 11.14±0.97 for WT, 15.34±1.10 for TFΔCT, p=0.007; strain rate-/s: 3.89±0.26 for WT, 5.18±0.21 for TFΔCT, p=0.0005). Histological analysis demonstrated that TFΔCT hearts had in the infarct area greater proliferation of endothelial cells and myofibroblasts accompanied with better scar formation. Compared with wild-type hearts, infarcted TFΔCT hearts showed less infiltration of proinflammatory cells with concomitant lower expression of protease-activated receptor-1 (PAR1)-Rac1 axis. Furthermore, infarcted TFΔCT hearts presented markedly higher peri-infarct vessel density associated with enhanced endothelial cell proliferation and higher expression of PAR2 and PAR2-associated pro-angiogenic pathway factors.

Conclusions

Our findings demonstrate that the TF cytoplasmic domain exacerbates post-infarct cardiac injury and adverse LV remodeling via differential regulation of inflammation and angiogenesis. Targeted inhibition of the TF cytoplasmic domain-mediated intracellular signaling may ameliorate post-infarct LV remodeling without perturbing coagulation.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): National University Health System of Singapore

O-083 Non-invasive, label-free optical analysis to detect aneuploidy within the inner cell mass of the preimplantation embryo

Study question

Can we separate between control and reversine-treated cells within the inner cell mass (ICM) of the mouse preimplantation embryo by using label-free and non-invasive hyperspectral microscopy?

Summary answer

Hyperspectral microscopy is able to discern between control and reversine-treated cells using cellular autofluorescence in the complete absence of fluorescence tags.

What is known already

Embryo mosaicism (containing cells that are euploid (46 chromosomes) and aneuploid (deviation from the expected number of chromosomes)) affects up to 17.3% of human blastocyst embryos. Current diagnosis of aneuploidy in the IVF clinic involves a biopsy of trophectoderm (TE) cells or spent media followed by sequencing. In some blastocyst embryos these approaches will fail to diagnose of the proportion of aneuploid cells within the fetal lineage (ICM).

Study design, size, duration

The impact of aneuploidy on cellular metabolism was assessed by using cellular autofluoresence and hyperspectral microscopy (broad spectral profile). Two models were employed: (i) Primary human fibroblast cells with known karyotypes (4-6 independent replicates, euploid n = 467; aneuploid n = 969) and reversine induced aneuploidy in mouse embryos (5-8 independent replicates, 30-44 cells per group). Both models were subjected to hyperspectral imaging to quantify native cell fluorescence.

Participants/materials, setting, methods

The human model is comprised of euploid (male and female) and aneuploid (triploid and trisomies: 13, 18, 21, XXX, and XXY) primary human fibroblast cells. For the mouse model, we treated embryos with reversine, a reversible spindle assembly checkpoint inhibitor, during the 4- to 8-cell division. Individual blastomeres were dissociated from control and reversine treated 8-cell embryos. Blastomeres were either imaged directly or used to generate chimeric blastocysts with differing ratios of control:reversine-treated cells.

Main results and the role of chance

Following unsupervised linear unmixing, the relative abundance of metabolic cofactors was quantified: reduced nicotinamide adenine dinucleotide (NAD(P)H) and flavins with the subsequent calculation of the optical redox ratio (ORR: Flavins/[NAD(P)H + Flavins]). Primary human fibroblast cells displayed an increase in the relative abundance of NAD(P)H with a decrease in flavins, leading to a significant reduction in the ORR for aneuploid cells (P < 0.05). The mouse embryos displayed an identical trend as the human model between control and reversine-treated embryos. Mathematical algorithms were applied and able to distinguish between (i) euploid and aneuploid primary human fibroblast cells, (ii) control and reversine-treated mouse blastomeres and (iii) chimeric blastocysts with differing ratios of control and reversine-treated cells. The accuracy of these separations was supported by receiver operating characteristic curves with areas under the curve. We also showed that hyperspectral imaging of the preimplantation embryo does not impact on embryo developmental competence, pregnancy outcome and offspring health in a mouse model. We believe the role of chance is low as both human somatic cells and mouse embryos showed a consistent shift in cellular metabolism in response to human fibroblast cells that are aneuploid and reversine treated mouse embryos.

Limitations, reasons for caution

Further validation of our approach could include sequencing of the ICM of individual blastocysts to determine the proportion of aneuploid cells in ICM and correlate this with the metabolic profile obtained through hyperspectral imaging.

Wider implications of the findings

With hyperspectral imaging able to discriminate between (i) euploid and aneuploid human fibroblast cells and (ii) control and reversine-treated mouse embryos, this could be an accurate, non-invasive and label-free optical imaging approach to assess mosaicism within the ICM of mouse embryos, potentially leading to a new diagnostic tool for embryos.

Trial registration number

Not applicable

[The role of neutrophil density in neutrophils-mediated inflammatory response induced by monosodium urate crystals]

Objective: To study the role of neutrophil density and molecular mechanism in neutrophils-mediated inflammatory response induced by monosodium urate (MSU) crystals. Methods: Polymorphonuclear neutrophils (PMNs) isolated from healthy human peripheral blood were treated with MSU crystals at different density (5×10(6)/ml, 20×10(6)/ml, 100×10(6)/ml) in vitro. The mean fluorescence intensity (MFI) of PMNs and production of reactive oxygen species (ROS) were detected by flow cytometry. The distribution of MSU crystals was observed by polarized light microscopy. The neutrophil extracellular traps (NETs) formation was detected by immune fluorescence. The cytokines in cell supernatant were measured by beads assay including interleukin 1β (IL-1β) , tumor necrosis factor α (TNFα) , interleukin 8 (IL-8) , interferon inducible protein 10 (IP-10) , macrophage inflammatory protein 1 (MIP-1) , monokine induced by interferon-γ (MIG) , macrophage inflammatory protein 1α (MIP-1α) , macrophage inflammatory protein 1β (MIP-1β) . Results: (1) After MSU crystal intervention, the side scatters (SSC) of neutrophils with medium-cell density (20×10(6)/ml) and high-cell density (100×10(6)/ml) were 128±13 and 93±9 respectively, both significantly lower than 170±19 in low-cell density (5×10(6)/ml) group.(2) Similarly, compared with low-cell density group, the MFI (lucifer yellow) of PMNs with high-cell density was 1.8±0.2, also significantly decreased (P<0.05). When co-treated with oxygenated adenosine triphosphate (oxATP), MFI of PMNs were all enhanced consistently. (3) In MSU crystals stimulated PMNs, after adding 2',7'-dichlorodihydrofluorescein diacetate, the MFI values were 0.85±0.32, 2.49±0.78, 4.54±1.02 in low cell density groups, medium cell density groups, and high cell density groups respectively, indicating that the generation of ROS was positively correlated with the increase of PMN density (P<0.05). After the intervention of oxATP, the ROS production was significantly reduced. (4) MSU crystal induced NETs formation, especially at high cell density. NETs formation promotes MSU crystal aggregation, which could be partially overcome by oxATP pretreatment. (5) The expression of cytokines were all significantly decreased in the supernatant of PMNs at high cell density exposed to MSU crystals compared with PMNs at medium cell density (P<0.05) . Conclusion: The PMN-mediated inflammation induced by MSU crystals is cell density dependent, and ATP may play a role in partially overcoming the process.

[Changes of BK(Ca) on vascular striaepericytes of D-galactose-induced aging model in guinea pigs]

Objective: The aging model of guinea pigs induced by D-galactose was set up to investigate the changes of BK(Ca) expression and function on cochlear pericytes and their relationship with age-related hearing loss. Methods: Thirty healthy 8-week-old guinea pigs were randomly divided into three groups, with 10 in each group: D-galactose aging model group, subcutaneous injection of D-galactose (500 mg/kg) daily for 6 weeks; saline control group, the same amount of saline was injected into the neck of the aging model group for 6 weeks; the blank control group, no treatment was performed. The threshold of auditory brainstem response (ABR) was detected. The content of BK(Ca) in the perivascular cells of the guinea pig cochlear cells was detected by immunofluorescence technique. The changes of peripheral current density and BK(Ca) current were detected by patch clamp technique. The data were analyzed by GraphPad Prism software. Results: Compared with the saline group and the control group, the ABR threshold and the amplitude of the wave I were significantly decreased in the aging model group, and the difference was statistically significant (P<0.01). Compared with the control group, the expression of BK(Ca) in the vascular pericytes of guinea pigs in the aging model group was significantly reduced (1.00±0.08 vs 0.27±0.03,the difference was statistically significant P<0.01), and the cell current density and BK(Ca) net current value were also significantly reduced with statistically significant (P<0.01). Conclusions: D-galactose can successfully induce guinea pig aging model, in which BK(Ca) expression decreases and net current value decreases in pericytes of cochlear striavascularis, and changes in BK(Ca) expression and function may be related to age-related hearing loss.

[Effects of transthyretin on biological behavior of retinal pigment epithelial cells and retinal microvascular epithelial cells]

Objective: To explore the effects of transthyretin (TTR) on biological behavior of retinal pigment epithelial cells (RPECs) and retinal microvascular epithelial cells (RMVECs). Methods: RPECs were cultured with exogenous TTR to explore the effect of TTR on the proliferation of RPECs. The expression of TTR of RPECs was silenced by TTR specific small interfering RNA and the expression of TTR was detected by using Western blotting to identify the efficacy of TTR silence. The level of vascular endothelial growth factor (VEGF) massage RNA was detected by using RT-PCR to identify the interaction between VEGF and TTR. The different proliferation and migration abilities of RMVECs with different expressions of TTR were measured by transwell system. Results: MTT assay showed that RPECs with 0 μmol/L TTR glowed faster than with 4 μmol/L TTR (t=18.08, P<0.0001). The expression level of TTR was decreased in the small interfering RNA group as compared with the negative control group (P<0.05). RT-PCR assay showed no differential expression of VEGF after the silencing of TTR (P>0.05). The transwell assay showed RMVECs with the silence of TTR proliferated more slowly than RMVECs without the treatment (t=4.901, P=0.0012), and also migrated more slowly (t=4.213, P=0.0029). Conclusions: TTR can inhibit the proliferation of RPECs and promote the proliferation and migration of RMVECs without the help of VEGF, the mechanism of which may be worth further study. (Chin J Ophthalmol, 2016, 52: 856-860).

Assessment of Migraineurs Referred to a Specialist Headache Clinic in Singapore: Diagnosis, Treatment Strategies, Outcomes, Knowledge of Migraine Treatments And Satisfaction

This study aimed to compare (i) migraineurs' diagnosis, treatment strategies and satisfaction when treated by community care physicians (CCPs) and at the specialist headache clinic; (ii) migraineurs' knowledge of migraine treatments and outcomes at baseline and at 3 months' interval. Thirty-eight patients were interviewed at baseline visit and 3 months after neurologist consultation, using a survey form which consisted of a series of self-designed questions, the MIDAS questionnaire and the SF-36 Health Survey. More patients were informed of the diagnosis of migraine by the neurologist than by CCPs. Compared with CCPs, the neurologist was more likely to employ preventive therapies, prescribe triptans and ask patients to keep a headache diary. Patients' number of days with headaches in the last 3 months, pain intensity, MIDAS score and five out of the eight SF-36 domain scores were significantly improved at the 3 months' interval ( P < 0.05) compared with baseline at the specialist headache clinic. More patients recognized migraine-specific therapies and reported satisfaction with treatment after the neurologist consultation. This is the first study detailing significant improvements in patients' clinical outcomes, knowledge of migraine treatments and satisfaction after consultation at a specialist headache clinic in Singapore.

[Lycopene protects against hypoxia/reoxygenation injury in mouse cardiomyocytes by inhibiting endoplasmic reticulum stress induced apoptosis]

OBJECTIVE

To investigate the effects of lycopene on primary cultured neonatal mouse cardiomyocytes with hypoxia/reoxgenation (H/R) injury and explore related mechanism.

METHODS

Primary cultured neonatal mouse cardiomyocytes were randomly divided to control group (control); lycopene group (5 μmol/L, lyc); H/R group (4 hours hypoxia followed by 6 hours reoxgenation); lycopene+ H/R group (lyc+ H/R, the cardiomyocytes were incubated with 5 μmol/L lycopene for 4 hours before H/R treatment). The cell viability of cardiomyocytes was assessed by CCK-8 assay. The apoptotic rate of cardiomyocytes was evaluated by flow cytometry using AnnexinV-PI double staining. Western blot was used to determine the GRP78, CHOP, Bax and Bcl-2 protein expression in cardiomyocytes. The mRNA expressions of ATF6、eIF2α and sXbp-1 were detected by real-time PCR. The fluorescence intensity for reactive oxygen species (ROS) in cardiomyocytes was measured with Olympus fluorescence microscope.

RESULTS

Compared to control group, the cell viability of cardiomyocytes was significantly reduced ((64.28±6.12)% vs. (100.00±4.98)%, P<0.01), the apoptotic rate ((24.42±1.76)% vs. (5.16±1.31)%, P<0.01) and ratio of Bax/Bcl-2 (2.33±0.20 vs. 1.00±0.09, P<0.01) significantly increased, the ATF6, eIF2α and sXbp-1 mRNA expression, the CHOP and GRP78 protein expression (1.98±0.15 vs. 1.00±0.12, 2.09±0.11 vs. 1.00±0.09) as well as fluorescence intensity for ROS ((262.13±22.03)% vs. (100.00±12.35)%) were markedly increased in H/R group (all P<0.01). Compared to the H/R group, pretreatment with lycopene markedly improved the cell viability of cardiomyocytes ((81.75±6.85)%, P<0.01), significantly decreased the apoptotic rate ((17.24±2.02)%, P<0.01) and ratio of Bax/Bcl-2(1.64±0.13, P<0.01), significantly down-regulated the mRNA expression levels of ATF6, eIF2α and sXbp-1, and the protein expression levels of CHOP (1.54±0.12) and GRP78 (1.53±0.12), significantly reduced the fluorescence intensity for ROS ((171.18±19.09)%, all P<0.01).

CONCLUSIONS

Lycopene could attenuate hypoxia/reoxygenation-injury in primary cultured neonatal mouse cardiomyocytes, possibly through inhibiting the ER stress and alleviating the ER stress-induced apoptosis.

Mild cold effects on hunger, food intake, satiety and skin temperature in humans

BACKGROUND

Mild cold exposure increases energy expenditure and can influence energy balance, but at the same time it does not increase appetite and energy intake.

OBJECTIVE

To quantify dermal insulative cold response, we assessed thermal comfort and skin temperatures changes by infrared thermography.

METHODS

We exposed healthy volunteers to either a single episode of environmental mild cold or thermoneutrality. We measured hunger sensation and actual free food intake. After a thermoneutral overnight stay, five males and five females were exposed to either 18°C (mild cold) or 24°C (thermoneutrality) for 2.5 h. Metabolic rate, vital signs, skin temperature, blood biochemistry, cold and hunger scores were measured at baseline and for every 30 min during the temperature intervention. This was followed by an ad libitum meal to obtain the actual desired energy intake after cold exposure.

RESULTS

We could replicate the cold-induced increase in REE. But no differences were detected in hunger, food intake, or satiety after mild cold exposure compared with thermoneutrality. After long-term cold exposure, high cold sensation scores were reported, which were negatively correlated with thermogenesis. Skin temperature in the sternal area was tightly correlated with the increase in energy expenditure.

CONCLUSIONS

It is concluded that short-term mild cold exposure increases energy expenditure without changes in food intake. Mild cold exposure resulted in significant thermal discomfort, which was negatively correlated with the increase in energy expenditure. Moreover, there is a great between-subject variability in cold response. These data provide further insights on cold exposure as an anti-obesity measure.

An overview of the new test stand for H⁻ ion sources at FNAL

A new test stand at Fermi National Accelerator Laboratory (FNAL) is being constructed to carry out experiments to develop and upgrade the present magnetron-type sources of H(-) ions of up to 80 mA at 35 keV in the context of the Proton Improvement Plan. The aim of this plan is to provide high-power proton beams for the experiments at FNAL. The technical details of the construction and layout of this test stand are presented, along with a prospective set of diagnostics to monitor the sources.

Tumour size and differentiation predict survival after liver resection for hepatocellular carcinoma arising from non-cirrhotic and non-fibrotic liver: a case-controlled study

AIMS

The aims of this study were to assess the outcomes of patients who underwent potentially curative hepatic resection for hepatocellular carcinoma (HCC) in a background of non-cirrhotic/non-fibrotic livers, and to determine prognostic factors that influenced survival.

METHODS

Over a 15-year period, all patients undergoing hepatectomy for HCC were identified. Collated data included demographics, laboratory analysis, operative findings and histo-pathological data. Survival differences between these factors following liver resection were determined.

RESULTS

57 patients were included with a median age of 70 years. The majority of patients underwent a hemi-hepatectomy or more radical resection (n = 37). Overall R0 resection rate was 90.4% (n = 51). The overall morbidity and mortality rates were 26.3% and 3.5%, respectively. The median follow-up period was 28 months. The 1-, 3- and 5- year disease-free survival was 65.4%, 41.8% and 39.1%, and the overall survival was 73.5%, 49.6% and 39.5%, respectively. AFP (p = 0.039) was the only predictor of poorer disease-free survival on univariate analysis. On multi-variable analysis, poorly differentiated tumour and large tumour size were independent predictors of overall survival.

CONCLUSIONS

Liver resection is a feasible treatment option for HCC in non-cirrhotic/non-fibrotic livers with good survival outcome. Tumour size and differentiation are adverse predictors of outcome in these patients.

Prediction of weight loss and regain following dietary, lifestyle, and pharmacologic intervention

To develop statistical models for predicting weight loss and regain, we analyzed the phenotypic responses in an outpatient study of 60 obese subjects randomized to one of three 12-week interventions, diet (-600 kcal) alone, diet with exercise, and diet with sibutramine. This was followed by 12 weeks of observation. The best of the "baseline covariates" models was one that incorporated intervention group and baseline homeostasis model assessment-estimated insulin resistance (HOMA(IR)). It predicted week 12 weight change with R(2) of 0.38 and root mean square error (√MSE) of 2.92 kg. An alternative model incorporating baseline fat mass plus change in weight and HOMA(IR) at week 4 improved the prediction (R(2), 0.67, √MSE, 2.19 kg). We could not identify a satisfactory model to predict weight regain. We conclude that prediction of weight loss over 12 weeks is significantly improved when short-term weight change is incorporated into the model. This information could be utilized to forecast the success of a weight-loss program and to motivate and contribute to innovative designing of obesity trials.

Effect of tea catechins on regulation of cell proliferation and antioxidant enzyme expression in H2 O2 -induced primary hepatocytes of goat in vitro

Tea catechins (TC) are polyphenols that have potent antioxidant activity. The objectives of this study were to determine the effects of TC on antioxidant status of hepatocytes challenged with H2 O2 . Primary hepatocytes of goat were exposed to 1 mm H2 O2 without or with 5, 50 and 500 μg/ml TC. The cells were harvested at 48 h post-treatment to determine effects of TC on proliferation, apoptotic features and membrane integrity of cells, and expression of genes and activities of antioxidant enzymes. H2 O2 exposure caused damage to cells (p < 0.001). A lower concentration of TC (5 μg/ml) displayed a protective effect by inhibiting exorbitant cell proliferation and DNA degradation. Both H2 O2 exposure and TC pre-incubation affected expression of antioxidant enzymes at mRNA and protein levels (p < 0.001). The activities of catalase (CAT) (p = 0.027), CuZn-superoxide dismutase (CuZn-SOD) (p < 0.001) and glutathione peroxidase (GPx) (p < 0.001) increased with TC pre-incubation followed by H2 O2 challenge. Changes of CuZn-SOD activity induced by H2 O2 and TC basically paralleled the changes in the corresponding mRNA and protein levels, but the correlation in CAT and GPx expression displayed slightly different patterns at different concentrations of TC. These findings infer that oxidative stress can induce deleterious cellular responses and this unfavourable condition may be alleviated by treatment with TC.

An integrated mathematical model of thrombin-, histamine-and VEGF-mediated signalling in endothelial permeability

BACKGROUND

Endothelial permeability is involved in injury, inflammation, diabetes and cancer. It is partly regulated by the thrombin-, histamine-, and VEGF-mediated myosin-light-chain (MLC) activation pathways. While these pathways have been investigated, questions such as temporal effects and the dynamics of multi-mediator regulation remain to be fully studied. Mathematical modeling of these pathways facilitates such studies. Based on the published ordinary differential equation models of the pathway components, we developed an integrated model of thrombin-, histamine-, and VEGF-mediated MLC activation pathways.

RESULTS

Our model was validated against experimental data for calcium release and thrombin-, histamine-, and VEGF-mediated MLC activation. The simulated effects of PAR-1, Rho GTPase, ROCK, VEGF and VEGFR2 over-expression on MLC activation, and the collective modulation by thrombin and histamine are consistent with experimental findings. Our model was used to predict enhanced MLC activation by CPI-17 over-expression and by synergistic action of thrombin and VEGF at low mediator levels. These may have impact in endothelial permeability and metastasis in cancer patients with blood coagulation.

CONCLUSION

Our model was validated against a number of experimental findings and the observed synergistic effects of low concentrations of thrombin and histamine in mediating the activation of MLC. It can be used to predict the effects of altered pathway components, collective actions of multiple mediators and the potential impact to various diseases. Similar to the published models of other pathways, our model can potentially be used to identify important disease genes through sensitivity analysis of signalling components.

Adequacy and change in nutrient and food intakes with aging in a seven-year cohort study in elderly women

OBJECTIVE

As women age total dietary intake falls which may increase the risk of dietary deficiencies in some individuals. The aims of this study were to investigate the changes in nutrient and dietary intakes that occurred with aging in a seven-year longitudinal study of elderly Australian women and to evaluate the adequacy of their dietary intakes.

DESIGN

Longitudinal population based study on health with ageing.

PARTICIPANTS AND SETTING

911 free-living elderly women aged 70-85 years at baseline from a cohort of 1500 elderly women.

MEASUREMENTS

At baseline, 60 and 84 months, self-reported Food Frequency Questionnaires (FFQ) and demographics were collected and anthropometry measured.

RESULTS

During the 84 month subjects lost height (1.8 cm) and body weight (1.9 kg). Intakes of energy and macronutrients carbohydrate, fat and protein declined significantly over the 84 months. Mean energy derived from saturated fat was above, whereas energy derived from carbohydrate was below, recommended levels of intake at all time points. Intakes of vitamins and minerals all declined with age and subjects had suboptimal intakes of folate, vitamin E and calcium at all time points. The serve sizes for potato and meat and the consumption of milk, bread and variety of vegetables declined significantly over time reflecting changes in nutrient intake.

CONCLUSIONS

Ageing is associated with reduced food intake resulting in inadequate intakes in energy, and some nutrients. Nutrition policy for elderly women should include advice to maintain or increase intakes of carbohydrate, milk, vegetables and fruit whilst continuing to reduce fat intake.

Virtual screening of selective multitarget kinase inhibitors by combinatorial support vector machines

Multitarget agents have been increasingly explored for enhancing efficacy and reducing countertarget activities and toxicities. Efficient virtual screening (VS) tools for searching selective multitarget agents are desired. Combinatorial support vector machines (C-SVM) were tested as VS tools for searching dual-inhibitors of 11 combinations of 9 anticancer kinase targets (EGFR, VEGFR, PDGFR, Src, FGFR, Lck, CDK1, CDK2, GSK3). C-SVM trained on 233-1,316 non-dual-inhibitors correctly identified 26.8%-57.3% (majority >36%) of the 56-230 intra-kinase-group dual-inhibitors (equivalent to the 50-70% yields of two independent individual target VS tools), and 12.2% of the 41 inter-kinase-group dual-inhibitors. C-SVM were fairly selective in misidentifying as dual-inhibitors 3.7%-48.1% (majority <20%) of the 233-1,316 non-dual-inhibitors of the same kinase pairs and 0.98%-4.77% of the 3,971-5,180 inhibitors of other kinases. C-SVM produced low false-hit rates in misidentifying as dual-inhibitors 1,746-4,817 (0.013%-0.036%) of the 13.56 M PubChem compounds, 12-175 (0.007%-0.104%) of the 168 K MDDR compounds, and 0-84 (0.0%-2.9%) of the 19,495-38,483 MDDR compounds similar to the known dual-inhibitors. C-SVM was compared to other VS methods Surflex-Dock, DOCK Blaster, kNN and PNN against the same sets of kinase inhibitors and the full set or subset of the 1.02 M Zinc clean-leads data set. C-SVM produced comparable dual-inhibitor yields, slightly better false-hit rates for kinase inhibitors, and significantly lower false-hit rates for the Zinc clean-leads data set. Combinatorial SVM showed promising potential for searching selective multitarget agents against intra-kinase-group kinases without explicit knowledge of multitarget agents.

Virtual screening of Abl inhibitors from large compound libraries by support vector machines

Abl promotes cancers by regulating cell morphogenesis, motility, growth, and survival. Successes of several marketed and clinical trial Abl inhibitors against leukemia and other cancers and appearances of reduced efficacies and drug resistances have led to significant interest in and efforts for developing new Abl inhibitors. In silico methods of pharmacophore, fragment, and molecular docking have been used in some of these efforts. It is desirable to explore other in silico methods capable of searching large compound libraries at high yields and reduced false-hit rates. We evaluated support vector machines (SVM) as a virtual screening tool for searching Abl inhibitors from large compound libraries. SVM trained and tested by 708 inhibitors and 65,494 putative noninhibitors correctly identified 84.4 to 92.3% inhibitors and 99.96 to 99.99% noninhibitors in 5-fold cross validation studies. SVM trained by 708 pre-2008 inhibitors and 65 494 putative noninhibitors correctly identified 50.5% of the 91 inhibitors reported since 2008 and predicted as inhibitors 29,072 (0.21%) of 13.56M PubChem, 659 (0.39%) of 168K MDDR, and 330 (5.0%) of 6638 MDDR compounds similar to the known inhibitors. SVM showed comparable yields and substantially reduced false-hit rates against two similarity based and another machine learning VS methods based on the same training and testing data sets and molecular descriptors. These suggest that SVM is capable of searching Abl inhibitors from large compound libraries at low false-hit rates.

Effect of powder calcination on the sintering of hydroxyapatite

The sintering behaviour of synthesized HA powder that was calcined at various temperatures ranging from 700 degrees C to 1000 degrees C was investigated in terms of phase stability, bulk density, Young's modulus and Vickers hardness. The calcination treatment resulted in higher crystallinity of the starting HA powder. Decomposition of HA phase to form secondary phases was not observed in all the calcined powders. The results also indicated that powder calcination (up to 900 degrees C) prior to sintering has negligible effect on the sinterability of the HA compacts. However, powder calcined at 1000 degrees C was found to be detrimental to the properties of sintered hydroxyapatite bioceramics.

Sintering behaviour of hydroxyapatite bioceramics

The sintering behaviour of a commercial HA and synthesized HA was investigated over the temperature range of 700 degrees C to 1400 degrees C in terms of phase stability, bulk density, Young's modulus and Vickers hardness. In the present research, a wet chemical precipitation reaction was successfully employed to synthesize a submicron, highly crystalline, high purity and single phase stoichiometric HA powder that is highly sinteractive particularly at low temperature regimes below 1100 degrees C. It has been revealed that the sinterability of the synthesized HA was significantly greater than that of the commercial HA. The temperature for the onset of sintering and the temperature required to achieve densities above 98% of theoretical value were approximately 150 degrees C lower for the synthesized HA than the equivalent commercial HA. Nevertheless, decomposition of HA phase upon sintering was not observed in the present work for both powders.

An evaluation of the effects of renal artery stenting in renovascular hypertension

Renal artery stenosis is a common cause (1-6%) of secondary hypertension. Renal artery stenting has recently been employed as an adjunct to antihypertensive medication. We evaluated 92 patients who underwent renal angiography of whom 30 were stented. There was a reduction (p < 0.01) in blood pressure immediately post renal artery stenting--systolic BP from 157 +/- 20 to 140 +/- 21 mmHg and diastolic BP from 81 +/- 13 to 72 +/- 12 mmHg was sustained at 6 months follow up (148 +/- 20/76 +/- 12 mmHg) in the outpatients' clinic. The amount of antihypertensive medication did not differ post stenting--2.7 +/- 1.2 pre vs 2.7 +/- 1.2 drugs post procedure. Renal artery stenting did not provide a 'cure' for any patient with atherosclerotic renovascular hypertension and until the results of randomized studies are known we believe use should be restricted.

Allogeneic bone marrow transplantation in a 7-year-old girl with congenital erythropoietic porphyria: a treatment dilemma

Congenital erythropoietic porphyria (CEP, Günther's disease) has a very variable phenotype. In the more severely affected, bone marrow transplantation (BMT) is potentially curative, but is not without risks. We describe a 7-year-old girl with CEP characterized by severe photosensitivity but only mild anaemia, in whom the difficult decision to proceed with allogeneic BMT was made after discussion in a multidisciplinary team. She has shown successful engraftment, accompanied by biochemical and clinical resolution of her metabolic disease. She remains well 3 years later, the oldest patient with CEP receiving BMT to survive beyond 12 months. However, she has experienced significant morbidity including florid cutaneous graft-versus-host disease with postinflammatory hypopigmentation. Her case is important in highlighting the delay in diagnosis not uncommon in this condition and the complex decision-making process involved in proceeding with BMT.

Messenger RNA levels of genes involved in dysregulation of postprandial lipoproteins in type 2 diabetes: the role of Niemann-Pick C1-like 1, ATP-binding cassette, transporters G5 and G8, and of microsomal triglyceride transfer protein

AIMS/HYPOTHESIS

The aim of the present study was to examine the relationship between chylomicron composition and expression of genes that regulate chylomicron production in the intestine. We examined expression of the following: (1) Niemann-Pick C1-like 1 (NPC1L1), which regulates cholesterol absorption; (2) ATP-binding cassette transporters G5 and G8 (ABCG5, ABCG8), which regulate cholesterol homeostasis through their ability to excrete enterocyte cholesterol back into the lumen of the intestine; and (3) microsomal triglyceride transfer protein (MTTP), which packages the chylomicron particle by assembling cholesterol, triglyceride, phospholipids and apolipoprotein B48.

SUBJECTS, MATERIALS AND METHODS

Type 2 diabetic (26) and non-diabetic (21) patients were examined. Levels of NPC1L1, ABCG5 and ABCG8 and MTTP mRNA were measured in duodenal biopsies by real-time PCR. Lipoproteins were isolated by sequential ultracentrifugation.

RESULTS

Diabetic patients had more NPC1L1 mRNA than the control subjects (p<0.02). Expression of ABCG5 and ABCG8 mRNA was lower in the diabetic patients (p<0.05) and MTTP expression was increased (p<0.05). There was a positive correlation between NPLC1L1 and MTTP mRNA (p<0.01) and a negative correlation between NPC1L1 and ABCG5 mRNA (p<0.001). Diabetic patients on statin therapy had increased ABCG5 and ABCG8 mRNA compared to those not on statin (p<0.02 and p<0.05) and less MTTP mRNA than those not on statin (p<0.05).

CONCLUSIONS/INTERPRETATION

This study demonstrates that in type 2 diabetes there are important alterations to the expression of intestinal genes that regulate cholesterol absorption and chylomicron synthesis. In diabetic patients statin therapy is associated with reduced MTTP expression and increased ABCG5 and ABCG8 mRNA. The study suggests new mechanisms to explain postprandial diabetic dyslipidaemia and the beneficial effect of statins.

Critical role of functional decline in delayed discharge from an acute geriatric unit

INTRODUCTION

Delayed hospital discharge of elderly patients after an acute illness poses significant problems, including bed-blockade, iatrogenesis, and increase in morbidity, dependency and social isolation. The aim of this study was to determine the factors associated with delayed discharge from an acute geriatric unit.

MATERIALS AND METHODS

This was a prospective cohort study involving 172 consecutive non-institutionalised patients, 65 years and older, admitted to an acute geriatric unit. The medical, functional, psychological and social variables of each subject were documented and any decline in functional status recorded. Based on the discharge status, patients were dichotomised into the "delayed" and "non-delayed" groups. Initial bivariate analyses of the variables were performed to select those associated with the "delayed discharge" group at the P < 0.05 levels. These variables were in turn entered into a multivariate logistic regression model to identify factors significantly associated with delayed discharge.

RESULTS

Forty-eight patients (27.9%) had their discharge from the acute geriatric care unit delayed despite clinically fit to be so. Variables significantly associated with delayed discharge in the multivariate model were: 1) decline in basic activities of daily living (ADL) status [P < 0.001; adjusted odds ratio (AOR), 3.63; 95% confidence interval (CI), 1.33 to 9.86] and 2) need for skilled nursing [P = 0.012; AOR, 4.57; 95% CI, 1.88 to 11.14].

CONCLUSIONS

The study demonstrates the central importance of effectively identifying elderly patients who are at risk of delayed discharge after acute hospitalisation through a multidisciplinary focus on illness-induced functional decline. It is likely therefore that proactive approaches to rehabilitation and caregiver training, and adequate community-based services, may facilitate early and effective return of these patients to their homes, thereby reducing inappropriate use of acute beds.

Cutaneous cryptococcus infection due to C. albidus associated with Sézary syndrome

Cryptococcus albidus is a non-neoformans species of the genus Cryptococcus and is a rare cause of disease. There have been only 13 previously reported cases of systemic disease in which this opportunistic yeast has been isolated from the lung, cerebrospinal fluid and blood. We report the first case of cutaneous Cryptococcus infection due to the species C. albidus, in a man with Sézary syndrome.

[Progress in the protective medicine against [correction of aganist] rocket propellents]

To review the progress in the major assignment, the organization and implementation of protection against liquid rocket propellent. The safety detection methods of the rocket [correction of rocked] propellent in the launching field were also discussed. Three steps of the sanitation and protection of the liquid propellent, the toxicity and the toxicology of hydrazine on central nervous system, blood circulatory system, assimilation system, respiratory system, immune system, liver, kidney, eye, skin and its hereditary toxicology were described. In addition, the clinical types of poisoning, the current principle and the common ways of the prevention and treatment of hydrazine and nitrogen oxides poisoning were summarized.

Analysis of corneal topography after excimer laser photorefractive keratectomy

Excimer laser photorefractive keratectomy (PRK) is an effective treatment for myopia. We investigated the magnitude of optical zone decentration and qualitative patterns of corneal topography after this treatment. We performed computer-assisted videokeratography on 44 myopic eyes (29 patients) that had undergone PRK before and 1, 6, and 12 months after the procedure. Associations of clinical outcomes with decentration and topographic patterns were assessed. The normalized scale of the topography 1 month postoperatively showed a mean decentration of 0.33 +/- 0.23 mm (range 0-0.9). Thirty-four eyes had decentration of less than 0.50 mm; 10 had an ablation zone decentered from 0.5 to 0.9 mm. Analysis of geometric mean visual acuities between eyes with less than 0.5 mm decentration and those with 0.5 to 0.9 mm decentration demonstrated minimal differences. No eye was decentered more than 1 mm. Four main ablation patterns were noted on subtraction analysis: homogeneous, semicircular, keyhole, and central island. Over time, the number of eyes with a homogeneous pattern increased. Eyes with a homogeneous ablation pattern had significantly better uncorrected visual acuity than those with other patterns. The mean visual acuity was 20/29.1 in the homogeneous group and 20/38.5 in the pooled irregular group 1 month postoperatively (p < 0.05). There was no significant difference among the four ablation patterns at 6 or 12 months after PRK. Topographic patterns were not significantly associated with best-corrected vision.

Neuroimaging guidelines in cognitive impairment: lessons from 3 cases of meningiomas presenting as isolated dementia

We report three cases of large intracranial meningiomas who presented with dementia alone and no accompanying focal neurological deficits. The meningiomas were detected solely as a result of a policy of routinely scanning the brains of patients presenting with early dementia. Dramatic improvements in the cognitive functions were noted following the excision of the tumours in two of the patients (the third passed away in the perioperative period). The implications of these cases with regard to deciding when to order a brain scan for patients presenting with isolated dementia are discussed in this article and a brief review of the relevant medical literature on this topic is also presented.

Molecular pathogenesis of alcohol withdrawal seizures: the modified lipid-protein interaction mechanism

The phrase alcohol withdrawal seizures (AWS) refers to seizures that result from the withdrawal of alcohol after a period of chronic alcohol administration. A mechanism of AWS is postulated, namely the modified lipid-protein interaction (MLPI) mechanism. This hypothesis is based upon an evaluation of the mechanisms of membrane fluidity, calcium channels, gamma-aminobutyric acid (GABA) and glutamate in the molecular pathogenesis of AWS. The mechanism hypothesizes that acute ethanol treatment alters the neuronal membrane lipids which then perturbs protein events, such as affecting the GABAA receptors, NMDA receptors and voltage-dependent Ca2+ channels synergistically or in combination. Subsequent adaptations in these systems occur after prolonged administration of ethanol. A sudden withdrawal of ethanol then leads to hyperexcitability which results in AWS.

Cardiac and systemic complications in multicentric reticulohistiocytosis

A 75-year-old man with a short history of cutaneous lesions of multicentric reticulohistiocytosis, preceded by a few months of a symmetrical polyarthritis is described. Within 5 months of onset of symptoms, he developed congestive cardiac failure secondary to pericardial involvement by the disease and succumbed despite therapy with cyclophosphamide and methylprednisolone. Post-mortem revealed the true extent of the disease, with nodules seen in the epiglottis and aryepiglottic folds, duodenal mesentery, pleura, pericardium and myocardium. Although the hallmarks of the disease are the papulonodular skin lesions, together with a severe, sometimes mutilating polyarthropathy, its widespread systemic nature is not often appreciated. We review five other cases in the literature with pericardial involvement and discuss aids to earlier diagnosis by synovial fluid cytology; gallium scanning is discussed as a potentially useful means of detecting the extent of systemic involvement in multicentric reticulohistiocytosis.

Delayed hypersensitivity reaction to heparin

We report a patient who developed a delayed hypersensitivity reaction to heparin. The literature relating to this type of adverse reaction to heparins is reviewed.

Adult onset Mongolian spot

We report a case of adult onset, unilateral, progressive, grey-blue pigmentation on the back of an Asian male. Histology showed the pigmentation to be due to deep dermal melanocytes. The spectrum of clinical presentations of dermal melanocytosis is reviewed and the unique features of this case outlined.