Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

In vitro photoprotective potential of aryl-sandwiched (thio)semicarbazones against UVA mediated cellular and DNA damage

The most prevalent solar ultraviolet radiation is ultraviolet-A (UVA) radiation. It is the inducer of reactive oxygen species (ROS), a potent mediator of inflammation and photocarcinogenesis. Regular application of sunscreens containing UVA filters is an effective preventive measure in mitigating the risk associated with the formation of dermal carcinoma. Therefore, the development of new photoprotective agents is of great need. The current work examined the in vitro photoprotection of the aryl-linked (thio)semicarbazone derivatives against UVA-mediated DNA damage, inflammation, reactive nitrogen species (RNS), and ROS. Except for the inflammatory cytokine assay, which was carried out on the human monocytic leukemia (THP-1) cell line, all tests were conducted on the human dermal fibroblast (BJ) cell line. In comparison to benzophenone (reference compound), the compound (2Z, 2'Z)-2,2'-(1,3-Phenylenebis (methanylylidene)) bis (hydrazine-1-carbothioamide) (DD-21) demonstrated considerable protection against UVA-induced damage. Compared to the UVA-irradiated control, DD-21 significantly decreased the levels of nitric oxide (NO) and ROS (p < 0.001). In the presence of DD-21, the release of UVA-induced pro-inflammatory cytokines, tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), was also significantly reduced (p < 0.05). Moreover, it was observed that DD-21 protected the cells from UVA-mediated DNA strand breaks and also inhibited the formation of cyclobutane pyrimidine dimers (CPDs) upon comparison to the UVA-exposed control cells (p < 0.001). In conclusion, the findings of this study revealed that DD-21 exhibits remarkable photoprotective properties, thus demonstrating its potential as a candidate UVA filter.

Part-II: an update of Schiff bases synthesis and applications in medicinal chemistry-a patent review (2016-2023)

INTRODUCTION

Schiff bases are compounds with characteristic features of azomethine linkage (-C=N-). Schiff bases are capable of coordinating with metal ions via azomethine nitrogen. Schiff base derivatives and their metal complexes are known for intriguing novel therapeutic properties. In organic synthesis, the Schiff base reaction is prime in creating the C-N bond. Synthetic accessibility and structural diversity are the salient features for facile synthesis of Schiff base hybrids via a condensation reaction between an aldehyde/ketone and primary amines.

AREA COVERED

This review aims to provide a comprehensive overview of the commendable medicinal applications of Schiff base derivatives and their metal complexes patented from 2016 to 2023.

EXPERT OPINION

Schiff base derivatives are exceptional molecules for their assorted applications in medicinal chemistry. Several Schiff base products are marketed as drugs, and plenty of room is available for the purposive synthesis of new compounds in a diverse pool of disciplines. Expansion in the derivatization of Schiff bases in innumerable directions with multitudinous applications makes them 'magical molecules.' These compounds have proved extraordinary, from medicinal chemistry to other fields outside medicine. This review covers the therapeutic importance of Schiff base derivatives and aims to cover the patents published in recent years (2016-2023).

Association of lipid metabolism-related metabolites with overweight/obesity based on the FTO rs1421085

Globally, obesity is a severe health issue. A more precise and practical approach is required to enhance clinical care and drug development. The FTO (fat mass and obesity-associated) gene variant rs1421085 is strongly associated with an increased susceptibility to obesity in numerous populations; however, the precise mechanism behind this association concerning metabolomics is still not understood. This study aims to examine the association between metabolites and obesity-related anthropometric traits based on the variant FTO rs1421085. This study was based on a case-control design involving a total of 542 participants including overweight/obese cases and healthy controls. The blood samples were collected from all the participants. The isolated serum samples were subjected to untargeted metabolomics using GC-MS. The isolated DNA samples were genotyped for the FTO rs1421085 variant. Initially, a total of 42 metabolites were identified on GC-MS, which were subjected to further association analyses. The study observed a significant association of two metabolites, glycerol and 2,3-dihydroxypropyl stearate with FTO gene variant rs1421085 and obesity-related anthropometric traits including % BF, WHtR, WC, and HC. The CT genotype of FTO rs1421085 may greatly increase the risk of overweight/obesity by changing the lipid metabolism-related metabolites. Therefore, this study highlights the significance of biochemical networks in the progression of obesity in carriers of the FTO rs1421085 risk genotype.

Racial differences in healthcare utilization among patients with suspected or diagnosed preeclampsia: A retrospective cohort study

OBJECTIVES

To analyze healthcare resource utilization and severe maternal morbidity (SMM) in Black and White patients with preeclampsia diagnosis versus signs/symptoms.

STUDY DESIGN

This was a retrospective cohort study analyzing data from the IBM® Explorys Database between 7/31/2012-12/31/2020. Demographic, clinical, and laboratory data were extracted. Healthcare utilization and SMM were analyzed during the antepartum period (20 weeks of gestation until delivery) among Black and White patients with signs/symptoms of preeclampsia, with a diagnosis of preeclampsia, or neither (control).

MAIN OUTCOME MEASURES

Healthcare utilization and SMM in those with a preeclampsia diagnosis or signs/symptoms of preeclampsia only were compared with a control group (White patients with no preeclampsia diagnosis or signs/symptoms).

RESULTS

Data from 38,190 Black and 248,568 White patients were analyzed. Patients with preeclampsia diagnosis or signs/symptoms were more likely to visit the emergency room compared to those without diagnosis or signs/symptoms. Black patients with signs/symptoms of preeclampsia had the highest elevated risk (odds ratio [OR] = 3.4), followed by Black patients with a preeclampsia diagnosis (OR = 3.2), White patients with signs/symptoms (OR = 2.2), and White patients with a preeclampsia diagnosis (OR = 1.8). More Black patients experienced SMM (SMM rate 6.1% [Black with preeclampsia diagnosis] and 2.6% [Black with signs/symptoms]) than White patients (5.0% [White with preeclampsia diagnosis] and 2.0% [White with signs/symptoms]). SMM rates were higher for Black preeclampsia patients with severe features than for White preeclampsia patients with severe features (8.9% vs 7.3%).

CONCLUSIONS

Compared with White patients, Black patients had higher rates of antepartum emergency care and antepartum SMM.

Interactive effects of FTO rs9939609 and obesogenic behavioral factors on adiposity-related anthropometric and metabolic phenotypes

Numerous genetic variants have been linked to obesity predisposition, however, the interplay of genetic and behavioral factors is very crucial in determining the final phenotype. Therefore, this study examined the interactive effects of the FTO rs9939609 and various obesogenic behavioral factors on adiposity-related anthropometric and metabolic phenotypes in a sample of Pakistani population. A total of 612 participants encompassing 306 overweight/obese (cases) and an equal number (306) of age- and sex-matched normal-weight (controls) individuals were included in the study. Adiposity-related anthropometric parameters were collected by taking corresponding body measurements by following standard procedures. The metabolic parameters were assessed by performing corresponding biochemical assays. A standard questionnaire was devised for the collection of adiposity-related behavioral information. The FTO rs9939609 was genotyped by employing TaqMan allelic discrimination assay. The data was analyzed by using SPSS software. Interactive effects of the FTO rs9939609 and behavioral factors on obesity-related anthropometric and metabolic phenotypes were examined via linear regression by adjusting potential confounders and making correction for multiple comparisons. The results implied that the interaction between the FTO rs9939609 and low physical activity may significantly increase various adiposity-related anthropometric variables (p < 0.05). However, no such interactive effects were found on any adiposity-related metabolic variable. In conclusion, the interaction between the FTO rs9939609 and low physical activity may have a significant impact on obesity-related anthropometric traits in the Pakistani population.

Outcome of percutaneous transhepatic biliary interventions in the management of biliary enteric anastomotic strictures with hepatolithiasis

AIM

To evaluate percutaneous transhepatic biliary interventions (PTBI) using the ADDFREE (Access-Drain-Dilate-Flush-REpeat periodically-Evaluate and remove) technique and its outcomes in patients with biliary enteric anastomotic strictures (BEAS) and hepatolithiasis.

MATERIAL AND METHODS

A retrospective review was undertaken of patients having hepatolithiasis with BEAS who underwent PTBI with a therapeutic intent (from January 2010 to January 2021) was performed. The technical and clinical successes of PTBI were analysed. Technical success was divided into duct access, crossing of BEAS, stricture resolution, and calculi clearance. Improvement of liver function tests, resolution of leucocytosis and presenting complaints were considered as clinical success. The patients were followed-up for a minimum duration of 6-months.

RESULTS

Eighteen patients received PTBI in form of the ADDFREE technique. Hepatolithiasis was bilobar (44.4%), unilobar in multiple ducts (unilobar-m; 27.8%) and unilobar in a single duct (unilobar-s; 27.8%) along with anastomotic stricture. The average number of sessions of stone clearance for bilobar, unilobar-m, and unilobar-s was 4.4 (±1.6), 3.6 (±2.4), and 1.5 (±0.5), respectively. Clinical success was observed in 14 (77.8%), while one patient had recurrence of calculi and received repeat treatment. Bile culture was positive for bacterial organisms in 17 (94.4%) patients. No major complication were seen while minor complication were seen in five patients consisting of self-limiting haemobilia (n=1), per-catheter bile leak (n=2) and aggravation of cholangitis (n=2).

CONCLUSION

PTBI, consisting of bile duct access, cholangioplasty, and calculi clearance, is a safe and effective technique for the treatment of patients having hepatolithiasis secondary to BEAS.

Barriers for using amoxycillin dispersible tablet in pediatric pneumonia treatment in Bangladesh

 

World Health Organization recommends guideline for integrated management of childhood illnesses (IMCI) where Amoxicillin Dispersible Tablet (DT) appears as the first drug of choice for treating childhood pneumonia. The Government of Bangladesh adopted the IMCI strategy in 1998, and scaled it up nationwide by 2014. But, even today, the use of Amoxicillin DT, either in public or private sector, for managing childhood pneumonia is a rare event in Bangladesh. We conducted this exploratory study to understand the existing barriers, both in public and private sector, those have influences on reduced availability of Amoxicillin DT and non-compliance of health service providers to follow IMCI guideline by using Amoxicillin DT for treating a child with pneumonia, in Bangladesh. We conducted desk review of relevant strategy and policy documents, key informant interviews with 19 key individuals from Ministry of Health and national / international NGOs. Collected information were analyzed and interpreted using thematic analysis method. Identified barriers through this study pointed to inadequate policy level focus on IMCI implementation, non-inclusion of Amoxicillin DT in the national essential drug list, single source of Amoxicillin DT producing pharmaceutical in the country coupled with bureaucracy and procurement procedural complexity, lack of training of health service providers and abundant availability of antibiotic over the counter. Study respondents recommended for policy level strengthening of IMCI program, increasing coverage of training for health care provider, including practicing pediatricians both at public and private sectors, facilitating production and procurement procedures and prohibiting antibiotic sell over the counter.

Key messages

• Facilitation of production and procurement procedure coupled with enforcement of law prohibiting antibiotics availability over the counter are urgent needs.

• Policy level support emphasizing full compliance of service providers for quality of implementation of IMCI program in Bangladesh (and similar other settings) is also important.

A Case of Bilateral Middle Cerebral Artery Stenosis with Unilateral M1 Stenting

Stroke is not only the third leading cause of death in Bangladesh but it also causes a high number of disability adjusted life years loss (485 per 10,000 people). Appropriate treatment of recurrent stroke has to be established. Here we present A 60 year's old male patient with history of recurrent stroke who came in our out patient department. He had progressing bilateral middle cerebral artery atherosclerotic stenosis (100.0% on right side and 52.0% on left side) which was less severs but symptomatic at dominant hemisphere (left). Percutaneous transluminal angioplasty with stenting was done to prevent further ischemia and to increase the blood supply of remaining brain parenchyma. On post stenting follow-up patient did not suffered from any new event of stroke for about 22 months. Percutaneous transluminal angioplasty with stenting is an effective procedure to prevent recurrent stroke for intracranial atherosclerotic disease.

Malignant Neuroendocrine Tumor of Gall Bladder: An Incidental Finding

Neuroendocrine tumor of the gallbladder is a rare gallbladder tumor with aggressive behavior and poor prognosis. Cholelithiasis is the most important risk factor for it. The clinical presentations of most patients are non-specific and vague abdominal pain is the most common initial symptom followed by cholecystitis, with obstructive jaundice, weight loss, ascites, pruritus or palpable mass and occasional associated endocrine manifestations. Surgery remains the main cornerstone for it. In January 2019, in the department of Hepatobiliary, Pancreatic and Liver transplant surgery in Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh, a 30-year-old female presented with incidental finding of gallbladder mass. Extended cholecystectomy was performed. Histopathology examination revealed small cell neuroectodermal tumor of the gallbladder.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Association of CLOCK gene variants with obesity and adiposity-related anthropometric, metabolic, and behavioral parameters

The CLOCK gene is a core component of the circadian clock and regulates various aspects of metabolism. Therefore, any variation that affects the function/expression of the CLOCK gene may contribute to the manifestation of metabolic disorders such as obesity. This study investigated whether the CLOCK variants rs4864548 and rs6843722 are associated with obesity and related traits in Pakistanis. A total of 306 overweight/obese cases and 306 age- and gender-matched control subjects were recruited (males 336 and females 276, age range 12–63 years). Anthropometric and metabolic parameters were taken by standard procedures and biochemical analyses, respectively. Behavior-related information was collected with a questionnaire. The genotypes of the variants were determined by allelic discrimination Taqman assays. Both variants were found to have a significant association with overweight/obesity according to the over-dominant model. The rs4864548 and rs6843722 were observed to escalate the risk of overweight/obesity by 1.611 ( p = 0.004) and 1.657 ( p = 0.002) times, respectively. These variants were also seen to be significantly associated with various other adiposity-related anthropometric parameters ( p < 0.05). However, no association of both variants with metabolic and behavioral parameters was observed ( p > 0.05). Thus, these variants may contribute to increasing the risk of overweight/obesity and related anthropometric traits in Pakistanis.

Response evaluation of locoregional therapies in combined hepatocellular-cholangiocarcinoma and intrahepatic cholangiocarcinoma versus hepatocellular carcinoma: a propensity score matched study

AIM

To evaluate the response of locoregional therapy (LRT) on combined hepatocellular-cholangiocarcinoma (cHCC-CC) and intrahepatic cholangiocarcinoma (IHC) and compare their outcomes with propensity matched hepatocellular carcinoma (HCC) patients.

MATERIALS AND METHODS

From January 2011 to July 2020, 13 patients with cHCC-CC (11 men, two women, median age 56 years) and 15 IHC patients (10 men, five women, median age 60 years) were compared with 101 HCC patients (79 men, 22 women, median age 60 years) after LRT. All tumours were proven histologically. Among the 13 cHCC-CC patients, 11 received transarterial chemoembolisation (TACE), one received microwave ablation (MWA) and one received TACE with radiofrequency ablation (RFA). Of 15 IHC patients, eight received TACE, five received RFA, and one received MWA, and one received TACE with RFA. Propensity score matching (PSM) was done with conditional logistic regression adjusted for age, type of LRT, tumour specific features and Child-Pugh score.

RESULTS

After LRT, on univariate analysis an objective response was seen in 30% of cHCC-CC and 53% of IHC patients. PSM analysis demonstrated shorter progression-free survival (PFS; cHCC-CC versus HCC: 1.5 versus 7.5 months; IHC versus HCC: 6 versus 14 months, p<0.05), overall survival (OS; cHCC-CC versus HCC: 12 versus 28 months; IHC versus HCC: 18 versus 34 months, p<0.005), and poor objective response (cHCC-CC versus HCC: 25% versus 91%; IHC versus HCC: 58% versus 88%, p<0.05) in cHCC-CC and IHC patients versus HCC patients. Hypovascular tumour, macrovascular invasion, and infiltrative appearance were independent prognostic factors for OS in IHC patients.

CONCLUSION

cHCC-CC and IHC are aggressive tumours with a poor objective response, greater distant progression of the disease and shorter PFS and OS post LRT as compared to HCC.

Effect of interaction between obesity-promoting genetic variants and behavioral factors on the risk of obese phenotypes

The studies investigating gene-gene and gene-environment (or gene-behavior) interactions provide valuable insight into the pathomechanisms underlying obese phenotypes. The Pakistani population due to its unique characteristics offers numerous advantages for conducting such studies. In this view, the current study was undertaken to examine the effects of gene-gene and gene-environment/behavior interactions on the risk of obesity in a sample of Pakistani population. A total of 578 adult participants including 290 overweight/obese cases and 288 normal-weight controls were involved. The five key obesity-associated genetic variants namely MC4R rs17782313, BDNF rs6265, FTO rs1421085, TMEM18 rs7561317, and NEGR1 rs2815752 were genotyped using the TaqMan allelic discrimination assays. The data related to behavioral factors, such as eating pattern, diet consciousness, the tendency toward fat-dense food (TFDF), sleep duration, sleep-wake cycle (SWC), shift work (SW), and physical activity levels were collected via a questionnaire. Gene-gene and gene-behavior interactions were analyzed by multifactor dimensionality reduction and linear regression, respectively. In our study, only TMEM18 rs7561317 was found to be significantly associated with anthropometric traits with no significant effect of gene-gene interactions were observed on obesity-related phenotypes. However, the genetic variants were found to interact with the behavioral factors to significantly influence various obesity-related anthropometric traits including BMI, waist circumference, hip circumference, waist-to-hip ratio, waist-to-height ratio, and percentage of body fat. In conclusion, the interaction between genetic architecture and behavior/environment determines the outcome of obesity-related anthropometric phenotypes. Thus, gene-environment/behavior interaction studies should be promoted to explore the risk of complex and multifactorial disorders, such as obesity.

Predicting anthropometric and metabolic traits with a genetic risk score for obesity in a sample of Pakistanis

Obesity is an outcome of multiple factors including environmental and genetic influences. Common obesity is a polygenic trait indicating that multiple genetic variants act synergistically to influence its expression. We constructed a genetic risk score (GRS) based on five genetic variants (MC4R rs17782313, BDNF rs6265, FTO rs1421085, TMEM18 rs7561317, and NEGR1 rs2815752) and examined its association with obesity-related traits in a sample of Pakistanis. The study involved 306 overweight/obese (OW/OB) and 300 normal-weight (NW) individuals. The age range of the study participants was 12-63 years. All anthropometric and metabolic parameters were measured for each participant via standard procedures and biochemical assays, respectively. The genetic variants were genotyped by allelic discrimination assays. The age- and gender-adjusted associations between the GRS and obesity-related anthropometric and metabolic measures were determined using linear regression analyses. The results showed that OW/OB individuals had significantly higher mean ranks of GRS than NW individuals. Moreover, a significant association of the GRS with obesity-related anthropometric traits was seen. However, the GRS did not appear to affect any obesity-related metabolic parameter. In conclusion, our findings indicate the combined effect of multiple genetic variants on the obesity-related anthropometric phenotypes in Pakistanis.

Multicomponent reactions (MCR) in medicinal chemistry: a patent review (2010-2020)

Introduction: Multicomponent reactions (MCR) has been utilized to synthesize a vast range of analogs belonging to diverse classes of heterocyclic compounds offering multidimensional pharmaceutical applications. The unique feature of MCR includes the synthesis of highly functionalized molecules in a single pot to build quick libraries of compounds of biological interest to identify new leads as potential therapeutic agents.Area covered: The current review article covers the patents published in the last decade in order to highlight the importance of multicomponent reactions for synthesizing complex-functionalized molecules of high biological significance.Expert opinion: Easily automated one-pot multicomponent reactions (MCRs) has demonstrated successful impact at different stages of the lead discovery, lead optimization, and pre-clinical process development arenas. Application of MCRs is the recent advancement in the field of drug design and discovery which will expectedly lead to the development of medicinally important heterocyclic compounds with a vast range of biological activities.

Association and interaction of the FTO rs1421085 with overweight/obesity in a sample of Pakistani individuals

PURPOSE

Genetic variants determine the predisposition of an individual to obesity in a given environment. The present study was conducted to seek an association of the FTO variant rs1421085 with overweight/obesity and related traits in 612 Pakistani subjects in a case-control manner (overweight/obese = 306 and non-obese = 306). Moreover, interaction effects of the rs1421085 and overweight/obesity on multiple metabolic traits were also investigated, which were never explored before in Pakistani as well as in any other population.

MATERIALS AND METHODS

Anthropometric traits were measured by standard procedures, while metabolic parameters were determined by biochemical assays. Genotyping of the rs1421085 was carried out by TaqMan allelic discrimination assay. The data were analysed using SPSS software version 19.

RESULTS

The study revealed a significant association of the rs1421085 with overweight/obese phenotype with respect to over-dominant model indicated by h-index. The CT genotype of the rs1421085 was observed to increase the risk of being overweight/obese by 1.583 times (95% CI 1.147-2.185, p = 0.005). The CT genotype was also found to be associated with higher values of all anthropometric variables (except height and waist-to-hip ratio). Moreover, the interaction between the CT genotype of the rs1421085 and overweight/obesity was found to influence several metabolic parameters (raised blood pressure, product of triglyceride and glucose index, triglyceride levels, LDL-C, VLDL-C, coronary risk index, atherogenic index, and triglyceride-to-HDL-C ratio).

CONCLUSION

In conclusion, the rs1421085 was found to be associated with overweight/obesity and related anthropometric traits independent of age and gender in Pakistani population. Moreover, this variant was found to influence various metabolic traits in the presence of overweight/obesity.

LEVEL OF EVIDENCE

Level III, case-control analytic study.

Association of the NEGR1 rs2815752 with obesity and related traits in Pakistani females

Introduction: The variant NEGR1 rs2815752 has recently been linked with obesity in Caucasians. However, a very limited number of studies have examined the association of the NEGR1 rs2815752 with overweight/obesity in non-Caucasians with no such study ever performed in Pakistani population. Therefore, the present study was undertaken to seek the association of the rs2815752 with overweight, obesity, and related traits in Pakistanis.Subjects and methods: The study involved 112 overweight/control pairs (total 224) and 194 obese/control pairs (total 388). Anthropometric parameters were measured by employing standard procedures. Metabolic parameters were determined by biochemical assays. Behavioral information was collected through a questionnaire. The rs2815752 was genotyped via TaqMan allelic discrimination assay. Regression analyses were employed to analyze the data in SPSS software.Results: The study revealed significant gender-specific association of the rs2815752 with obesity (OR 3.03; CI 1.19-7.72, p = 0.020) and some obesity-related anomalous anthropometric traits (weight, BMI, waist circumference, hip circumference, and abdominal and supra-iliac skinfold thicknesses) in females according to dominant model (h = 0.023). However, no association of the rs2815752 with obesity-related behavioral and metabolic parameters was observed.Conclusion: The NEGR1 rs2815752 may be associated with obese phenotype and some of the related anthropometric traits in Pakistani females.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Metabolic implications of circadian disruption

Circadian rhythms are generated by the circadian clock, a self-sustained internal timing system that exhibits 24-h rhythms in the body. In mammals, circadian rhythms are driven by a central clock located in suprachiasmatic nucleus and various peripheral clocks located in different tissues and organs of the body. Many cellular, behavioral, and physiological processes are regulated by the circadian clock in coordination with environmental cues. The process of metabolism is also under circadian regulation. Loss of synchronization between the internal clock and environmental zeitgebers results in disruption of the circadian rhythms that seriously impacts metabolic homeostasis leading to changed eating behavior, altered glucose and lipid metabolism, and weight gain. This in turn augments the risk of having various cardio-metabolic disorders such as obesity, diabetes, metabolic syndrome, and cardiovascular disease. This review sheds light on circadian rhythms and their role in metabolism with the identification of gaps in the current knowledge that remain to be explored in these fields. In this review, the molecular mechanisms underlying circadian rhythms have been elaborated first. Then, the focus has been kept on explaining the physiological significance of circadian rhythms in regulating metabolism. Finally, the implications for metabolism when these rhythms are disrupted due to genetic mutations or social and occupational needs enforced by modern lifestyle have been discussed.

Bayesian strategy selection identifies optimal solutions to complex problems using an example from GP prescribing

Complex health problems require multi-strategy, multi-target interventions. We present a method that uses machine learning techniques to choose optimal interventions from a set of possible interventions within a case study aiming to increase General Practitioner (GP) discussions of physical activity (PA) with their patients. Interventions were developed based on a causal loop diagram with 26 GPs across 13 clinics in Geelong, Australia. GPs prioritised eight from more than 80 potential interventions to increase GP discussion of PA with patients. Following a 2-week baseline, a multi-arm bandit algorithm was used to assign optimal strategies to GP clinics with the target outcome being GP PA discussion rates. The algorithm was updated weekly and the process iterated until the more promising strategies emerged (a duration of seven weeks). The top three performing strategies were continued for 3 weeks to improve the power of the hypothesis test of effectiveness for each strategy compared to baseline. GPs recorded a total of 11,176 conversations about PA. GPs identified 15 factors affecting GP PA discussion rates with patients including GP skills and awareness, fragmentation of care and fear of adverse outcomes. The two most effective strategies were correctly identified within seven weeks of the algorithm-based assignment of strategies. These were clinic reception staff providing PA information to patients at check in and PA screening questionnaires completed in the waiting room. This study demonstrates an efficient way to test and identify optimal strategies from multiple possible solutions.

Association of the Variant rs7561317 Downstream of the TMEM18 Gene with Overweight/Obesity and Related Anthropometric Traits in a Sample of Pakistani Population

Obesity is a multifactorial disorder and requires favorable environment for its expression. However, some individuals are more prone to weight gain than others in an obesogenic environment. Thus, at individual level, who becomes overweight or obese is mostly determined by genetic factors. The current study was undertaken to explore for the first time the association of the TMEM18 rs7561317 variant with overweight/obesity and related anthropometric, metabolic, physical, and behavioral traits in a sample of Pakistani population with association between the rs7561317 and many traits was not investigated before in any population. The current study involved a total of 612 subjects including 306 overweight/obese and equal number of age- and sex-matched normal weight individuals. Obesity-related parameters were determined and the variant was genotyped by allelic discrimination assay. All the aforementioned associations were assessed by regression analyses adjusted for covariates and corrected for multiple comparisons. The results revealed a significant association of the TMEM18 rs7561317 with overweight/obese phenotype in more than one genetic model. Therefore, h-index (degree of dominance) was calculated, which indicated the recessive mode of inheritance for the above-said association. Similarly, a significant association of the rs7561317 with obesity-related anthropometric traits and clinical surrogate markers of visceral adiposity was observed. Thus, GG genotype of the rs7561317 was found to increase 1.74 times the risk of overweight/obesity in Pakistani population (OR = 1.74, 95% CI 1.210-2.496, p = 0.003) while low physical activity seemed to accentuate the TMEM18 rs7561317-associated risk of overweight/obesity (OR = 2.696, 95% CI 1.485-4.896, p = 0.004).

Association of BDNF rs6265 and MC4R rs17782313 with metabolic syndrome in Pakistanis

The current case-control study sought the association of BDNF rs6265 and MC4R rs17782313 with metabolic syndrome (MetS), MetS components and other related metabolic parameters in a sample of Pakistani subjects. Fasting high-density lipoprotein cholesterol (HDL-C) and homeostatic model assessment of insulin sensitivity showed a significantly lower mean whereas body mass index (BMI), waist circumference, systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose, insulin, total cholesterol (TC), low-density lipoprotein cholesterol, very-low-density lipoprotein cholesterol, triglycerides (TG), cholesterol to HDL-C ratio, TG to HDL-C ratio, homeostatic model assessment of insulin resistance, visceral adiposity index, lipid accumulation product and the product of TG and glucose showed a significantly higher mean in the presence of MetS. Reduced HDL-C appeared as the most frequent and hypertriglyceridemia as the least frequent component of MetS whereas clustering of reduced HDL-C + abdominal obesity (AO) + hyperglycemia appeared as the most prevalent combination of MetS components. Moreover, BDNF rs6265 showed BMI and gender independent association with increased risk of MetS in Pakistani individuals whereas MC4R rs17782313 showed BMI and gender dependent association with increased risk of MetS in Pakistani females. In addition, BDNF rs6265 and MC4R rs17782313 showed gender-dependent associations with decreased risk of having low HDL-C in males and increased risk of having abdominal obesity in females, respectively. However, no association was observed for metabolic variables other than components of MetS across genotypes of both BDNF rs6265 and MC4R rs17782313.

Intestinal Tuberculosis: A Rare Case of Massive Gastrointestinal Bleed in a Post-Renal Transplant Recipient

Massive rectal bleeding is an uncommon presentation of ileal tuberculosis (TB). We report an uncommon cause of anemia in a post-renal transplant patient due to massive lower gastrointestinal (LGI) bleed. The index case had a normal upper and LGI endoscopy, but the ⁹⁹technetium labeled red blood cell scan showed active bleeding from terminal ileum and caecum. Microscopic examination of the resected specimen revealed tubercular granuloma with acid-fast bacilli. Intestinal TB should be a differential diagnosis for massive LGI bleed in immunosuppressed patients in developing country.

Benzo(a)pyrene, an Active Product of Cigarette Smoke, Role in PLA2 Isoforms Activation in Colon Cancer

Background and aim: One of the active combustion product of cigarette smoke, Benzo[a]pyrenes, role in pulmonary cancer is clearly understood. However, its role in gastrointestinal cancer including colon cancer is not clearly understood. Methods: In this study, benzo(a)pyrenes was treated to colon cells to evaluate its role in cell viability, cellular ROS, and gene expression of various PLA2 isoforms was evaluated by FACS and PCR. The identified PLA2 was silenced at the gene level to evaluate its role in cell viability and ROS generation. Results: B(a)P treatment at 1 µg/mL for 48 h to HCT-15 male colon cells significantly reduced the cell viability without affecting HT-29 female colon cells. Higher doses and longer treatment duration with B(a)P showed that female colon cells were highly sensitive than male colon cells. Annexin-V/PI staining for preapoptotic detection showed that B(a)P treatment increased the apoptosis in both the cell types in a concentration and time-dependent manner. The cytosolic ROS (cROS) and superoxide radical (SOR) formation in the female colon cells was significantly higher than male colon cells unlike the mitochondrial ROS (mtROS) production which was significantly higher in male colon cells. Treatment with B(a)P significantly upregulated the IID and IVA PLA2 isoform groups in HCT-15 male colon cells, whereas IB was upregulated in HT-29 female colon cells among the various PLA2 isozyme gene studied (IB, IID, III, IVA, IVB, IVC, VI, X, aiPLA2 and iPLA2). Gene silencing experiments targeting PLA2 IID and IVA in the HCT-15 male colon cells and IB in HT-29 female colon cells showed no effect with B(a)P treatment on the cell proliferation, apoptosis, membrane integrity and free radicals (ROS, mtROS, and SOR) generation. Conclusion: Targeting specific PLA2 isozymes in a cell-specific manner abolished the B(a)P-induced PLA2-mediated oxidative damage–related signaling pathways.