Preoperative dietitian-led Very Low Calorie Diet (VLCD) Clinic for adults living with obesity undergoing gynaecology, laparoscopic cholecystectomy and hernia repair procedures: a pilot parallel randomised controlled trial.

Obesity can increase the risk of postoperative complications. Despite increased demand for patients living with obesity to lose weight prior to common surgical procedures, the impact of intentional weight loss on surgical outcomes is largely unknown. We aimed to conduct a pilot study to assess the feasibility of a full-scale randomised controlled trial (RCT) to examine the effect of preoperative dietitian-led Very Low Calorie Diet (VLCD) Clinic on surgical outcomes in gynaecology and general surgeries. Between August 2021 and January 2023, a convenience sample of adults living with obesity (BMI ≥ 30 kg/m2) awaiting gynaecology, laparoscopic cholecystectomy and ventral hernia repair procedures were randomised to dietitian-led VLCD (800-1000 kcal using meal replacements and allowed foods), or control (no dietary intervention), 2-12 weeks preoperatively. Primary outcome was feasibility (recruitment, adherence, safety, attendance, acceptability and quality of life (QoL)). Secondary outcomes were anthropometry and 30-d postoperative outcomes. Outcomes were analysed as intention-to-treat. Fifty-one participants were recruited (n 23 VLCD, n 28 control), mean 48 (sd 13) years, 86 % female, and mean BMI 35·8 (sd 4·6) kg/m2. Recruitment was disrupted by COVID-19, but other thresholds for feasibility were met for VLCD group: high adherence without unfavourable body composition change, high acceptability, improved pre/post QoL (22·1 ± 15 points, < 0·001), with greater reductions in weight (-5·5 kg VLCD v. -0·9 kg control, P < 0·05) waist circumference (-6·6 cm VLCD v. +0·6 control, P < 0·05) and fewer 30-d complications (n 4/21) than controls (n 8/22) (P > 0·05). The RCT study design was deemed feasible in a public hospital setting. The dietitian-led VLCD resulted in significant weight loss and waist circumference reduction compared with a control group, without unfavourable body composition change and improved QoL.

Impact of a dietitian-led very low calorie diet clinic on perioperative risk for patients with obesity awaiting elective, non-bariatric surgery: A retrospective cohort study.

BACKGROUND: Despite a lack of evidence that intentional weight loss reduces the risk of postoperative complications, adults with obesity are commonly asked to lose weight before elective surgery. We hypothesized that patients undertaking dietitian-led preoperative, very low calorie diet treatment could reduce perioperative surgery risks, as per validated risk scoring systems. The purpose of this study was to measure the impact of a dietitian-led preoperative very low calorie diet clinic on the American Society of Anesthesiologists physical status scores and National Surgical Quality Improvement Program Surgical Risk Calculator scores for patients with obesity awaiting non-bariatric elective surgery. METHODS: This retrospective cohort study included patients referred to the preoperative dietitian-led very low calorie diet clinic before elective surgical procedures over a 2-year-9-month period. The dietitian prescribed individualized, very low calorie diet-based treatment. Primary outcomes were changes in the American Society of Anesthesiologists and Surgical Risk Calculator scores from pretreatment until surgery. RESULTS: A total of 141 eligible participants (48 ± 13.4 years, 76% women, body mass index 41.7 ± 6.3 kg/m2) demonstrated clinically significant weight loss (mean 7.1 ± 6.1kg, 5.2% body weight, P < .001). Median treatment duration was 13 weeks (interquartile range 6.2-19.2 weeks). Five participants (3.5%) avoided surgery due to weight loss-related improvements in their condition. American Society of Anesthesiologists scores improved for 16% (n = 22/141) of participants. Overall, the median surgical risk calculator estimated risk of 'serious' and 'any' postoperative complication reduced from 4.8% to 3.9% (P < .001) and 6% to 5.1% (P < .001), respectively. Reduction in all Surgical Risk Calculator scores occurred, including surgical site infection, re-admission, and cardiac events (P < .05). CONCLUSION: The dietitian-led preoperative, very low calorie diet clinic improved American Society of Anesthesiologists and Surgical Risk Calculator scores for non-bariatric elective surgery patients with obesity. Randomized controlled trials comparing this approach with a control group are warranted.

A Review of Bio-Based Activated Carbon Properties Produced from Different Activating Chemicals during Chemicals Activation Process on Biomass and Its Potential for Malaysia.

Activated carbon is the preferred adsorbent for gas and water treatment in various industry across the world due to its efficiency, reliability, and accessibility. Recently, in Malaysia, studies are mainly focused on the fabrication of activated carbon from lignocellulosic biomass-based precursors from agricultural waste such as coconut shell, rice husk, and palm kernel shell. Activated carbon fabrication is a two-step process; the precursor will first undergo carbonization, then, activation is carried out either physically or chemically to develop its porous surface for adsorption purposes. The main benefit of activated carbon is the customizable pore structure for different utilization, which can be easily achieved by the chemical activation process. The types and concentration of chemicals used for activation, pre-treatment of precursor, duration of the activation process, and the mass ratio of precursor to chemicals are proven to effectively influence the resulting pore structure. However, the chemicals used in the activation process can be harmful to the environment. Thus, the chemical recovery process is necessary after the activation process. Nonetheless, more in-depth research on producing activated carbon from abundant biomass materials with bio-based chemical agents for activation is needed to achieve an ecological and sustainable manufacturing process.

Effect of Cellulose Nanofibrils on the Properties of Jatropha Oil-Based Waterborne Polyurethane Nanocomposite Film.

The objective of this work was to study the influence of cellulose nanofibrils (CNF) on the physical, mechanical, and thermal properties of Jatropha oil-based waterborne polyurethane (WBPU) nanocomposite films. The polyol to produce polyurethane was synthesized from crude Jatropha oil through epoxidation and ring-opening method. The chain extender, 1,6-hexanediol, was used to improve film elasticity by 0.1, 0.25, and 0.5 wt.% of CNF loading was incorporated to enhance film performance. Mechanical performance was studied using a universal test machine as specified in ASTM D638-03 Type V and was achieved by 0.18 MPa at 0.5 wt.% of CNF. Thermal gravimetric analysis (TGA) was performed to measure the temperature of degradation and the chemical crosslinking and film morphology were studied using Fourier-transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy (FESEM). The results showed that when the CNF was incorporated, it was found to enhance the nanocomposite film, in particular its mechanical and thermal properties supported by morphology. Nanocomposite film with 0.5 wt.% of CNF showed the highest improvement in terms of tensile strength, Young's modulus, and thermal degradation. Although the contact angle decreases as the CNF content increases, the effect on the water absorption of the film was found to be relatively small (<3.5%). The difference between the neat WPBU and the highest CNF loading film was not more than 1%, even after 5 days of being immersed in water.

Effect of a hypertonic balanced ketone solution on plasma, CSF and brain beta-hydroxybutyrate levels and acid-base status.

PURPOSE: Although glucose is the main source of energy for the human brain, ketones play an important role during starvation or injury. The purpose of our study was to investigate the metabolic effects of a novel hypertonic sodium ketone solution in normal animals. METHODS: Adult Sprague-Dawley rats (420-570 g) were divided into three groups of five, one control and two study arms. The control group received an intravenous infusion of 3 % NaCl at 5 ml/kg/h. The animals in the two study arms were assigned to receive one of the two formulations of ketone solutions, containing hypertonic saline with 40 and 120 mmol/l beta-hydroxybutyrate, respectively. This was infused for 6 h and then the animal was euthanized and brains removed and frozen. RESULTS: Both blood and cerebrospinal fluid (CSF) levels of beta-hydroxybutyrate (BHB) demonstrated strong evidence of a change over time (p < 0.0001). There was also strong evidence of a difference between groups (p < 0.0001). Multiple comparisons showed all these means were statistically different (p < 0.05). Measurement of BHB levels in brain tissue found strong evidence of a difference between groups (p < 0.0001) with control: 0.15 mmol/l (0.01), BHB 40: 0.19 mmol/l (0.01), and BHB 120: 0.28 mmol/l (0.01). Multiple comparisons showed all these means were statistically different (p < 0.05). There were no differences over time (p = 0.31) or between groups (p = 0.33) or an interaction between groups and time (p = 0.47) for base excess. CONCLUSION: The IV infusions of hypertonic saline/BHB are feasible and lead to increased plasma, CSF and brain levels of BHB without significant acid/base effects.

Modeling biodegradation and kinetics of glyphosate by artificial neural network.

An artificial neural network (ANN) model was developed to simulate the biodegradation of herbicide glyphosate [2-(Phosphonomethylamino) acetic acid] in a solution with varying parameters pH, inoculum size and initial glyphosate concentration. The predictive ability of ANN model was also compared with Monod model. The result showed that ANN model was able to accurately predict the experimental results. A low ratio of self-inhibition and half saturation constants of Haldane equations (< 8) exhibited the inhibitory effect of glyphosate on bacteria growth. The value of K(i)/K(s) increased when the mixed inoculum size was increased from 10(4) to 10(6) bacteria/mL. It was found that the percentage of glyphosate degradation reached a maximum value of 99% at an optimum pH 6-7 while for pH values higher than 9 or lower than 4, no degradation was observed.

Approaches to sensitizing glioblastoma to radiotherapy: use of lentiviral vectors.

Glioblastoma multiforme (GBM) is the most common primary brain tumour and extirpation followed by radio- and chemotherapy has had minimal impact on the median survival of patients which is still less than one year. Hence, a novel therapeutic modality is required if the survival of patients with this disease is to be improved. ATM, mutated in the human genetic disorder ataxia-telangiectasia (A-T), plays a central role in the response to DNA double strand breaks and patients with this disorder are characterised by extreme sensitivity to radiation, increased risk of cancer and neurodegeneration. Thus, ATM represents a potential target for radiosensitization of brain tumour cells. A safe, non-replicating lentivirus is used to abrogate ATM in GBM through the antisense and RNAi approaches for radiosensitization. With either techniques, ATM protein was reduced by >90% and there was a 3­fold sensitization of GBM cells to radiation. ATM protein activation as well as ATM pS1981 foci formation were defective and downstream signalling determined by Ser15 phosphorylation on p53 was reduced. Success in the approaches provides a novel and exciting strategy for the treatment of GBM and thus improving the survival of patients with these tumours.

Development, characterization and commercial application of palm based dihydroxystearic acid and its derivatives: an overview.

Hydroxyl fatty acids and their derivatives are of high value due to their wide range of industrial application, including cosmetic, food, personal care and pharmaceutical products. Realizing the importance of hydroxyl fatty acids, and yet due to the absence of the conventional starting raw materials, Malaysia has developed 9,10-dihydroxystearic acid (9,10-DHSA) and its derivatives from locally abundant palm based oils. The aim of this article is to provide a general description of the works that have thus far being done on palm based 9,10-DHSA: starting from its conception and production from commercial grade palm based crude oleic acid via epoxidation and hydrolysis, purification through solvent crystallization and characterization through wet and analytical chemistry, moving on to developmental works done on producing its derivatives through blending, esterification, amidation and polymerization, and completing with applications of 9,10-DHSA and its derivatives, e.g. DHSA-stearates and DHSA-estolides, in commercial products such as soaps, deodorant sticks and shampoos. This article incorporates some of the patent filed technological knowhow on 9,10-DHSA and its derivatives, and will also point out some of the shortcomings in previously published documents and provide some recommendations for future research works in mitigating these shortcomings.

Management of primary rectal cancer by surgeons in Atlantic Canada: results of a regional survey.

BACKGROUND: We sought to determine the current practice patterns of general surgeons in Atlantic Canada in the management of primary rectal cancer in relation to surgeon-specific variables. METHODS: We sent mail-out surveys to all practising general surgeons (n = 183) in Atlantic Canada to determine screening preferences, preoperative assessment, the use of neoadjuvant and adjuvant therapy, surgical therapy for rectal cancer and surgeon demographics. We analyzed the responses using χ(2) tests. RESULTS: The response rate was 98 (54%) after 2 mail-outs; there were 82 (49%) eligible responses. Surgeons in practice for 21 years or more were more likely than those with fewer than 21 years of practice to order preoperative ultrasonography of the liver and were less likely to order preoperative computed tomography. Endorectal ultrasonography was ordered routinely by 23% of surgeons, whereas 71% of surgeons would order it if time and resources were available. Surgeons who were not certified by the Royal College of Physicians and Surgeons of Canada were significantly more likely than those who were certified to use neoadjuvant therapy in all patients with rectal cancer (43% v. 12%; p = 0.031). Surgeons who performed more than 10 rectal cancer surgeries per year were significantly more likely than those who performed 10 or fewer surgeries per year to use neoadjuvant treatment for T3 tumours (94% v. 61%; p = 0.007). Surgeons with medical or radiation oncology services in their communities were significantly more likely than those without such services to recommend neoadjuvant treatment in T3 rectal tumours and rectal tumours with pathologic lymph nodes. CONCLUSION: We found significant variation in the management of rectal cancer depending on surgeon-specific variables. The implications of these differences on the outcomes of patients with rectal cancer are unknown.

Results of a phase I dendritic cell vaccine trial for malignant astrocytoma: potential interaction with adjuvant chemotherapy.

Dendritic cell vaccination has been applied to the treatment of a variety of cancers, including malignant astrocytoma. We have treated 13 patients with malignant astrocytoma using dendritic cell vaccination and have shown that this treatment is safe and is likely to be effective in combination with standard adjuvant therapy. Future studies should prospectively incorporate dendritic cell vaccination together with chemotherapy. Ideally, dendritic cell vaccination should be tested in a prospective fashion, in a coordinated trial involving multiple centres.

T-cell apoptosis in human glioblastoma multiforme: implications for immunotherapy.

We used immunohistochemistry and flow cytometry to assess apoptosis in human glioblastoma multiforme (GBM). Our immunohistochemical study revealed apoptosis of glioma cells expressing glial fibrillary acidic protein and of CD3(+) T cells infiltrating GBM. To quantify and phenotype the apoptotic T cells, we performed flow cytometry on lymphocytes separated from GBM. The cells were stained with annexin-V-FLUOS/propidium iodide to identify apoptosis. We found that high proportions of both the CD4(+) and CD8(+) T cells were apoptotic. In particular, we found that T cells expressing Fas ligand (Fas-L, CD95L) were eight times more vulnerable to apoptosis than those not expressing Fas-L, which suggests that the T-cell apoptosis is induced by overactivation of the T-cell receptor, possibly in the absence of appropriate costimulation. Our results have implications for the design of immunotherapies for GBM.

Robust CDMA multiuser detection using a neural-network approach.

Abstract-Recently, a robust version of the linear decorrelating detector (LDD) based on the Huber's M-estimation technique has been proposed. In this paper, we first demonstrate the use of a three-layer recurrent neural network (RNN) to implement the LDD without requiring matrix inversion. The key idea is based on minimizing an appropriate computational energy function iteratively. Second, it will be shown that the M-decorrelating detector (MDD) can be implemented by simply incorporating sigmoidal neurons in the first layer of the RNN. A proof of the redundancy of the matrix inversion process is provided and the computational saving in realistic network is highlighted. Third, we illustrate how further performance gain could be achieved for the subspace-based blind MDD by using robust estimates of the signal subspace components in the initial stage. The impulsive noise is modeled using non-Gaussian alpha-stable distributions, which do not include a Gaussian component but facilitate the use of the recently proposed geometric signal-to-noise ratio (G-SNR). The characteristics and performance of the proposed neural-network detectors are investigated by computer simulation.