MC4R variant rs17782313 and manifestation of obese phenotype in Pakistani females

MC4R represents a key player involved in melanocortin-mediated control of energy balance. Recently identified near MC4R variant rs17782313 (T > C) can serve as a contributing factor for obese phenotype but its association with obesity has never been sought in a sample of the Pakistani population. The role of genetic variants as causal factors varies across populations. Association studies in a specific population can help us to distinguish global from local gene–gene and gene–environment interactions. This is the first study that investigated the association of rs17782313 with obesity and various obesity-linked anthropometric, metabolic, physical, and behavioural traits in Pakistani subjects including 306 OW/OB (overweight and obese) and 300 NW (normal weight) individuals. The comparison of various aforementioned obesity-linked continuous and categorical variables between OW/OB and NW subjects revealed that almost all variables were found significantly aberrant (p < 0.05) in OW/OB subjects as compared to their age- and gender-matched NW controls indicating greater risk of developing various cardio-metabolic disorders. The genotyping of rs17782313 showed significant association of this variant with obesity and obesity-linked anthropometric traits in females suggesting the gender-specific effect of this variant in our population. The minor allele C increased the risk of obesity by 1.55 times (95% CI = 1.1–2.18, p = 0.01) whereas homozygous CC genotype increased the risk by 2.43 times (95% CI = 1.19–4.96, p = 0.015) in females. However, no association of rs17782313 was observed with any of the obesity-linked metabolic, physical, and behavioural traits except random eating timings. In conclusion, the current study significantly contributes to the knowledge of the genetic proneness to obesity in Pakistani females. This could also be helpful for forthcoming meta-analysis studies elucidating which variants are truly associated with the susceptibility to develop an obese phenotype.

The current study significantly contributes to the knowledge of the genetic proneness to obesity in Pakistani females and could also be helpful for forthcoming meta-analysis studies.

Facile fabrication of epoxy-TiO2 nanocomposites: A critical analysis of TiO2 impact on mechanical properties and toughening mechanisms

Optimized ultrasonic assisted dispersion of un-functionalized titanium dioxide (TiO₂) nanoparticles (0.5-20wt%) into epoxy resin is reported. The investigation shows that there is a direct relation among nanoparticles content, inter-particle spacing and cluster size of the particles on the glass transition temperature (T_g) and tensile properties of the prepared nanocomposites. A significant improvement in tensile strength and modulus with minimal detrimental effect on the toughness was observed for the prepared composites, where compared to pristine epoxy resins, about 26% and 18% improvement in tensile strength and strain-to-break %, respectively, was observed for 10wt% particles loading, whereas a maximum improvement of about 54% for tensile toughness was observed for 5wt% particles loaded resins. The investigations found that a strong particle-matrix interface results in the enhancement of the mechanical properties due to leading toughening mechanisms such as crack deflection, particle pull out and plastic deformation.

Entanglement and Coherence in Quantum State Merging

Understanding the resource consumption in distributed scenarios is one of the main goals of quantum information theory. A prominent example for such a scenario is the task of quantum state merging, where two parties aim to merge their tripartite quantum state parts. In standard quantum state merging, entanglement is considered to be an expensive resource, while local quantum operations can be performed at no additional cost. However, recent developments show that some local operations could be more expensive than others: it is reasonable to distinguish between local incoherent operations and local operations which can create coherence. This idea leads us to the task of incoherent quantum state merging, where one of the parties has free access to local incoherent operations only. In this case the resources of the process are quantified by pairs of entanglement and coherence. Here, we develop tools for studying this process and apply them to several relevant scenarios. While quantum state merging can lead to a gain of entanglement, our results imply that no merging procedure can gain entanglement and coherence at the same time. We also provide a general lower bound on the entanglement-coherence sum and show that the bound is tight for all pure states. Our results also lead to an incoherent version of Schumacher compression: in this case the compression rate is equal to the von Neumann entropy of the diagonal elements of the corresponding quantum state.

Greatly reduced risk of EBV reactivation in rituximab-experienced recipients of alemtuzumab-conditioned allogeneic HSCT

EBV-associated post-transplant lymphoproliferative disease (PTLD) remains an important complication of allogeneic haematopoietic stem cell transplantation (allo-HSCT). We retrospectively analysed the incidence and risk factors for EBV reactivation in 186 adult patients undergoing consecutive allo-HSCT with alemtuzumab T-cell depletion at a single centre. The cumulative incidence of EBV reactivation was 48% (confidence interval (CI) 41-55%) by 1 year, with an incidence of high-level EBV reactivation of 18% (CI 13-24%); 8 patients were concurrently diagnosed with PTLD. Amongst patients with high-level reactivation 31/38 (82%) developed this within only 2 weeks of first EBV qPCR positivity. In univariate analysis age⩾50 years was associated with significantly increased risk of EBV reactivation (hazard ratio (HR) 1.54, CI 1.02-2.31; P=0.039). Furthermore, a diagnosis of non-Hodgkin lymphoma (NHL) was associated with greatly reduced risk of reactivation (HR 0.10, CI 0.03-0.33; P=0.0001) and this was confirmed in multivariate testing. Importantly, rituximab therapy within 6 months prior to allo-HSCT was also highly predictive for lack of EBV reactivation (HR 0.18, CI 0.07-0.48; P=0.001) although confounding with NHL was apparent. Our data emphasise the risk of PTLD associated with alemtuzumab. Furthermore, we report the clinically important observation that rituximab, administered in the peri-transplant period, may provide effective prophylaxis for PTLD.

Assisted Distillation of Quantum Coherence

We introduce and study the task of assisted coherence distillation. This task arises naturally in bipartite systems where both parties work together to generate the maximal possible coherence on one of the subsystems. Only incoherent operations are allowed on the target system, while general local quantum operations are permitted on the other; this is an operational paradigm that we call local quantum-incoherent operations and classical communication. We show that the asymptotic rate of assisted coherence distillation for pure states is equal to the coherence of assistance, an analog of the entanglement of assistance, whose properties we characterize. Our findings imply a novel interpretation of the von Neumann entropy: it quantifies the maximum amount of extra quantum coherence a system can gain when receiving assistance from a collaborative party. Our results are generalized to coherence localization in a multipartite setting and possible applications are discussed.

Antioxidant and hepatoprotective effect of polyphenols from apple pomace extract via apoptosis inhibition and Nrf2 activation in mice

Industrial apple pomace, a biowaste generated during apple processing, is rich in cell wall polysaccharides and phenolics. These biologically active compounds are reported to be highly beneficial from the nutritional and health point of view. In the present study, the total phenolic content in the apple pomace aqueous extract (APE) was estimated and evaluated for its possible antioxidant and hepatoprotective efficacy in carbon tetrachloride (CCl₄)-induced liver injury mice model. The aqueous extract exhibited 2,2-diphenyl-2-picrylhydrazyl free radical scavenging activity in vitro. Under in vivo study, mice were treated with APE (200 mg and 400 mg/kg body weight) for 2 weeks prior to the administration of CCl₄ (30% v/v). The serum liver injury markers alanine transaminase, aspartate transaminase, and alkaline phosphatase were significantly lowered by APE in a dose-dependent manner. The levels of antioxidant parameters superoxide dismutase (SOD), reduced glutathione (redGSH), and lipid peroxidation were also improved by APE in liver homogenate. Histopathological studies revealed that APE treatment significantly lowered the CCl₄-induced necrotic changes in the liver. Furthermore, terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end-labeling assay showed that CCl₄-induced apoptosis in the liver was significantly inhibited by APE in a dose-dependent manner. Immunohistochemistry results showed higher expression of nuclear erythroid 2-related factor 2 (Nrf2) in the liver of the APE-treated mice, a key regulator of antioxidative response. In conclusion, the results of the present study revealed the hepatoprotective efficacy of APE by inhibiting CCl₄-induced apoptosis, which is due to its antioxidant activity and the ability to induce Nrf2 protein expression.

Lack of association of the NPAS2 gene Ala394Thr polymorphism (rs2305160:G>A) with risk of chronic lymphocytic leukemia

BACKGROUND

NPAS2 is a product of the circadian clock gene. It acts as a putative tumor suppressor by playing an important role in DNA damage responses, cell cycle control and apoptosis. Chronic lymphocytic leukemia (CLL) appears to be an apoptosis related disorder and alteration in the NPAS2 gene might therefore be directly involved in the etiology of CLL. Here, the Ala394Thr polymorphism (rs2305160:G>A) in the NPAS2 gene was genotyped and melatonin concentrations were measured in a total of seventy-four individuals, including thirty-seven CLL cases and an equal number of age- and sex-matched healthy controls in order to examine the effect of NPAS2 polymorphism and melatonin concentrations on CLL risk in a Pakistani population.

MATERIALS AND METHODS

Genotyping of rs2305160:G>A polymorphism at NPAS2 locus was carried out by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). Melatonin concentrations were determined by enzyme linked immunosorbent assay (ELISA). Statistical analysis was performed using Statistical Package for Social Sciences software.

RESULTS

Our results demonstrated no association of the variant Thr genotypes (Ala/ Thr and Thr/Thr) with risk of CLL. Similarly, no association of rs2305160 with CLL was observed in either females or males after stratification of study population on a gender basis. Moreover, when the subjects with CLL were further stratified into shift-workers and non-shift-workers, no association of rs2305160 with CLL was seen in either case. However, significantly low serum melatonin levels were observed in CLL patients as compared to healthy subjects (p<0.05). Also, lower melatonin levels were seen in shift-workers as compared to non-shift-workers (p<0.05). There was no significant difference (p>0.05) in the melatonin levels across NPAS2 genotypes in all subjects, subjects with CLL who were either shift workers or non-shift-workers. General Linear Model (GLM) univariate analysis revealed no significant association (p>0.05) of the rs2305160 polymorphism of the NPAS2 gene with melatonin levels in any of the groups.

CONCLUSIONS

While low melatonin levels and shift-work can be considered as one of the risk factors for CLL, the NPAS2 rs2305160 polymorphism does not appear to have any association with risk of CLL in our Pakistani population.

Bradykinin-activated contractile signalling pathways in human myometrial cells are differentially regulated by arrestin proteins

Bradykinin is associated with infections and inflammation, which given the strong correlation between uterine infection and preterm labour may imply that it could play a role in this process. Therefore, we investigated bradykinin signalling, and the roles that arrestin proteins play in their regulation in human myometrial cells. Bradykinin induced rapid, transient intracellular Ca(2+) increases that were inhibited following B2 receptor (B2R) antagonism. Arrestin2 or arrestin3 depletion enhanced and prolonged bradykinin-stimulated Ca(2+) responses, and attenuated B2R desensitisation. Knockdown of either arrestin enhanced B2R-stimulated ERK1/2 signals. Moreover, depletion of either arrestin elevated peak-phase p38-MAPK signalling, yet only arrestin3 depletion prolonged B2R-induced p38-MAPK signals. Arrestin2-knockdown augmented bradykinin-induced cell movement. Bradykinin stimulates pro-contractile signalling mechanisms in human myometrial cells and arrestin proteins play key roles in their regulation. Our data suggest bradykinin not only acts as an utertonin, but may also have the potential to enhance the contractile environment of the uterus.

Detection of metastases in oral squamous cell carcinoma: still a diagnostic impasse

Oral squamous cell carcinoma (OSCC) being the most common malignancy of the oral cavity poses a significant public health problem due its impact on the speech, mastication, taste, swallowing and esthetics. Moreover, the presence of metastasis either regional or distant worsens the prognosis and reduces the survival rate in these patients. This makes it imperative to diagnose metastasis at an early stage to facilitate appropriate therapeutic management to reduce the morbidity and mortality associated with this disease. There have been several modalities that have been developed and in wide-use for recognition of metastasis with their inherent advantages and disadvantages making it a perplexing dilemma to the clinician and surgeon alike. This paper aims to give an insight into the diagnostic workup available for the evaluation of metastasis in patients with OSCC and reinforces the need for further research to develop more accurate methods.

Whole-genome sequencing reveals complex mechanisms of intrinsic resistance to BRAF inhibition

BACKGROUND

BRAF is mutated in ∼42% of human melanomas (COSMIC. http://www.sanger.ac.uk/genetics/CGP/cosmic/) and pharmacological BRAF inhibitors such as vemurafenib and dabrafenib achieve dramatic responses in patients whose tumours harbour BRAF(V600) mutations. Objective responses occur in ∼50% of patients and disease stabilisation in a further ∼30%, but ∼20% of patients present primary or innate resistance and do not respond. Here, we investigated the underlying cause of treatment failure in a patient with BRAF mutant melanoma who presented primary resistance.

METHODS

We carried out whole-genome sequencing and single nucleotide polymorphism (SNP) array analysis of five metastatic tumours from the patient. We validated mechanisms of resistance in a cell line derived from the patient's tumour.

RESULTS

We observed that the majority of the single-nucleotide variants identified were shared across all tumour sites, but also saw site-specific copy-number alterations in discrete cell populations at different sites. We found that two ubiquitous mutations mediated resistance to BRAF inhibition in these tumours. A mutation in GNAQ sustained mitogen-activated protein kinase (MAPK) signalling, whereas a mutation in PTEN activated the PI3 K/AKT pathway. Inhibition of both pathways synergised to block the growth of the cells.

CONCLUSIONS

Our analyses show that the five metastases arose from a common progenitor and acquired additional alterations after disease dissemination. We demonstrate that a distinct combination of mutations mediated primary resistance to BRAF inhibition in this patient. These mutations were present in all five tumours and in a tumour sample taken before BRAF inhibitor treatment was administered. Inhibition of both pathways was required to block tumour cell growth, suggesting that combined targeting of these pathways could have been a valid therapeutic approach for this patient.

Radiobiological impact of planning techniques for prostate cancer in terms of tumor control probability and normal tissue complication probability

Background:

The radiobiological models describe the effects of the radiation treatment on cancer and healthy cells, and the radiobiological effects are generally characterized by the tumor control probability (TCP) and normal tissue complication probability (NTCP).

Aim:

The purpose of this study was to assess the radiobiological impact of RapidArc planning techniques for prostate cancer in terms of TCP and normal NTCP.

Subjects and Methods:

A computed tomography data set of ten cases involving low-risk prostate cancer was selected for this retrospective study. For each case, two RapidArc plans were created in Eclipse treatment planning system. The double arc (DA) plan was created using two full arcs and the single arc (SA) plan was created using one full arc. All treatment plans were calculated with anisotropic analytical algorithm. Radiobiological modeling response evaluation was performed by calculating Niemierko's equivalent uniform dose (EUD)-based Tumor TCP and NTCP values.

Results:

For prostate tumor, the average EUD in the SA plans was slightly higher than in the DA plans (78.10 Gy vs. 77.77 Gy; P = 0.01), but the average TCP was comparable (98.3% vs. 98.3%; P = 0.01). In comparison to the DA plans, the SA plans produced higher average EUD to bladder (40.71 Gy vs. 40.46 Gy; P = 0.03) and femoral heads (10.39 Gy vs. 9.40 Gy; P = 0.03), whereas both techniques produced NTCP well below 0.1% for bladder (P = 0.14) and femoral heads (P = 0.26). In contrast, the SA plans produced higher average NTCP compared to the DA plans (2.2% vs. 1.9%; P = 0.01). Furthermore, the EUD to rectum was slightly higher in the SA plans (62.88 Gy vs. 62.22 Gy; P = 0.01).

Conclusion:

The SA and DA techniques produced similar TCP for low-risk prostate cancer. The NTCP for femoral heads and bladder was comparable in the SA and DA plans; however, the SA technique resulted in higher NTCP for rectum in comparison with the DA technique.

Common variant of FTO gene, rs9939609, and obesity in Pakistani females

Numerous studies confirmed the association of FTO (fat mass and obesity associated gene) common variant, rs9939609, with obesity in European populations. However, studies in Asian populations revealed conflicting results. We examined the association of rs9939609 variant of FTO gene with obesity and obesity-related anthropometric and metabolic parameters in Pakistani population. Body weight, height, waist circumference, hip circumference, and blood pressure (BP) were measured. BMI and waist-to-hip ratio (WHR) were calculated. Levels of fasting blood glucose (FBG), insulin, leptin, and leptin receptors were measured by enzyme linked immunosorbent assay (ELISA), and homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. The results showed association of FTO gene, rs9939609, with obesity in females (>18 years of age). FTO minor allele increased the risk of obesity by 2.8 times (95% CI = 1.3-6.0) in females. This allele showed association with body weight, BMI, waist circumference, hip circumference, WHR, BP, plasma FBG levels, HOMA-IR, plasma insulin levels, and plasma leptin levels. In conclusion, FTO gene, rs9939609, is associated with BMI and risk of obesity in adult Pakistani females. Association of rs9939609 variant with higher FBG, plasma insulin, and leptin levels indicates that this polymorphism may disturb the metabolism in adult females and predispose them to obesity and type 2 diabetes. However, the above-mentioned findings were not seen in children or males.

Verification of dose calculation algorithms in a multi-layer heterogeneous phantom using films

The development of advanced radiation treatment techniques such as intensity modulated radiation therapy (IMRT) and volumetric intensity modulated arc therapy (VMAT) require more accurate dose calculation algorithms within the treatment planning systems (TPS) considering that the human body is composed of tissues of widely differing radiological properties and the characteristics of a therapeutic radiation treatment beam along a heterogeneous path will be different. The objective of this study was to evaluate the accuracy of 2D-isodose distributions predicted by pencil beam convolution algorithm (PBC) and anisotropic analytic algorithm (AAA) in a heterogeneous slab phantom composed of media equivalent to air, water and bone density. The measurements were done by using the films at multiple depths in the phantom for open field sizes 5 × 5 cm2 and 10 × 10 cm2. The results from this study indicated that the AAA had better agreement with the measurement compared to PBC for both the test field sizes at all selected depths; however, the limitation of AAA in predicting doses within and beyond low-density medium was observed, especially for a smaller field size (up to 32.7% and 34.0% for AAA and PBC, respectively). Furthermore, discrepancies up to -4.8% for AAA and -14.6% for PBC was seen in the high-density medium as well. Dose prediction errors by the AAA and PBC were more pronounced for a smaller test field size, especially in the low-density medium.

KEYWORDS

IMRT, dose calculation algorithms, Anisotropic Analytical Algorithm (AAA), Pencil Beam Convolution (PBC), Varian's Eclipse treatment planning system.