Stacking dependence of carrier transport properties in multilayered black phosphorous

We present the effect of different stacking orders on carrier transport properties of multi-layer black phosphorous. We consider three different stacking orders AAA, ABA and ACA, with increasing number of layers (from 2 to 6 layers). We employ a hierarchical approach in density functional theory (DFT), with structural simulations performed with generalized gradient approximation (GGA) and the bandstructure, carrier effective masses and optical properties evaluated with the meta-generalized gradient approximation (MGGA). The carrier transmission in the various black phosphorous sheets was carried out with the non-equilibrium green's function (NEGF) approach. The results show that ACA stacking has the highest electron and hole transmission probabilities. The results show tunability for a wide range of band-gaps, carrier effective masses and transmission with a great promise for lattice engineering (stacking order and layers) in black phosphorous.

Abstract P5-03-03: Designing a novel platinum chemotherapeutic (IO-125) for treatment of breast cancer

Triple-negative breast cancer (TNBC) is an aggressive form of cancer occurring in 15-20% of breast cancer patients, with most patients relapsing on currently approved therapy. Recent studies have shown activity of platinum chemotherapy in this class of patients. IO-125 is a novel platinum (II) chemotherapeutic agent with an unique coordination environment. In this study, we investigated the anti-tumor activity of IO-125 in pre-clinical models of TNBC.

The coordination environment in IO-125 facilitates supramolecular assembly and releases diaminocyclohexane (DACH)-platinum in a sustained pH-dependent manner. In vitro cell viability studies using an array of breast cancer cell lines shows IO-125 exerts increased potency compared to carboplatin or oxaliplatin. The maximum tolerated (platinum-equivalent) dose (MTD) of IO-125 in mice was 8-fold higher than the MTD (platinum-equivalent) dose of oxaliplatin. The biodistribution and pharmacokinetic profile of IO-125 in plasma and tumor revealed preferential tumor accumulation, significantly increased area-under-the-curve (AUC), a reduction in clearance (CL) and a longer terminal half-life (42 hours) in comparison to oxaliplatin (18 hours). In addition, DNA-Pt adduct formation in tumors was significantly higher for IO-125. When administered at their respective MTDs, IO-125 led to sustained regression of the tumor in a 4T1 syngeneic breast cancer model. Based on these observations, we conclude that IO-125 may emerge as a novel therapeutic against triple negative breast cancer.

Citation Format: Sengupta A, Roy M, Sarkar A, Mylavarapu S, Modi S, Gupta N, B H, Hossain S, Ansari A, Pandey M, Yadav Y, Sengupta S. Designing a novel platinum chemotherapeutic (IO-125) for treatment of breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-03-03.

MicroRNAs as biomarkers of resilience or vulnerability to stress

Identifying novel biomarkers of resilience or vulnerability to stress could provide valuable information for the prevention and treatment of stress-related psychiatric disorders. To investigate the utility of blood microRNAs as biomarkers of resilience or vulnerability to stress, microRNAs were assessed before and after 7days of chronic social defeat in rats. Additionally, microRNA profiles of two important stress-regulatory brain regions, the medial prefrontal cortex (mPFC) and basolateral amygdala (BLA), were assessed. Rats that displayed vulnerability to subsequent chronic stress exhibited reductions in circulating miR-24-2-5p, miR-27a-3p, miR-30e-5p, miR-3590-3p, miR-362-3p, and miR-532-5p levels. In contrast, rats that became resilient to stress displayed reduced levels of miR-139-5p, miR-28-3p, miR-326-3p, and miR-99b-5p compared to controls. In the mPFC, miR-126a-3p and miR-708-5p levels were higher in vulnerability compared to resilient rats. In the BLA, 77 microRNAs were significantly altered by stress but none were significantly different between resilient and vulnerable animals. These results provide proof-of-principle that assessment of circulating microRNAs is useful in identifying individuals who are vulnerable to the effects of future stress or individuals who have become resilient to the effects of stress. Furthermore, these data suggest that microRNAs in the mPFC but not in the BLA are regulators of resilience/vulnerability to stress.

HEPNet: A Knowledge Base Model of Human Energy Pool Network for Predicting the Energy Availability Status of an Individual

HEPNet is an electronic representation of metabolic reactions occurring within human cellular organization focusing on inflow and outflow of the energy currency ATP, GTP and other energy associated moieties. The backbone of HEPNet consists of primary bio-molecules such as carbohydrates, proteins and fats which ultimately constitute the chief source for the synthesis and obliteration of energy currencies in a cell. A series of biochemical pathways and reactions constituting the catabolism and anabolism of various metabolites are portrayed through cellular compartmentalization. The depicted pathways function synchronously toward an overarching goal of producing ATP and other energy associated moieties to bring into play a variety of cellular functions. HEPNet is manually curated with raw data from experiments and is also connected to KEGG and Reactome databases. This model has been validated by simulating it with physiological states like fasting, starvation, exercise and disease conditions like glycaemia, uremia and dihydrolipoamide dehydrogenase deficiency (DLDD). The results clearly indicate that ATP is the master regulator under different metabolic conditions and physiological states. The results also highlight that energy currencies play a minor role. However, the moiety creatine phosphate has a unique character, since it is a ready-made source of phosphoryl groups for the rapid synthesis of ATP from ADP. HEPNet provides a framework for further expanding the network diverse age groups of both the sexes, followed by the understanding of energetics in more complex metabolic pathways that are related to human disorders.

Targeting channelrhodopsin-2 to ON-bipolar cells with vitreally administered AAV Restores ON and OFF visual responses in blind mice

Most inherited retinal dystrophies display progressive photoreceptor cell degeneration leading to severe visual impairment. Optogenetic reactivation of retinal neurons mediated by adeno-associated virus (AAV) gene therapy has the potential to restore vision regardless of patient-specific mutations. The challenge for clinical translatability is to restore a vision as close to natural vision as possible, while using a surgically safe delivery route for the fragile degenerated retina. To preserve the visual processing of the inner retina, we targeted ON bipolar cells, which are still present at late stages of disease. For safe gene delivery, we used a recently engineered AAV variant that can transduce the bipolar cells after injection into the eye's easily accessible vitreous humor. We show that AAV encoding channelrhodopsin under the ON bipolar cell-specific promoter mediates long-term gene delivery restricted to ON-bipolar cells after intravitreal administration. Channelrhodopsin expression in ON bipolar cells leads to restoration of ON and OFF responses at the retinal and cortical levels. Moreover, light-induced locomotory behavior is restored in treated blind mice. Our results support the clinical relevance of a minimally invasive AAV-mediated optogenetic therapy for visual restoration.

Efficient removal of arsenic (V) from water using steel-making slag

This study describes the potential use of steel-making slag as an arsenic-removal medium. Systematic analysis of slag material revealed a composition of oxides of calcium, iron, silicon, and phosphorous. Under the experimental conditions of this study, the equilibrium time was shown to be 2 hours, and the removal capacity to be 99%, with an adsorbent loading capacity of 1.25g/l. The adsorption kinetics were shown to follow a pseudo-second-order rate equation, and the adsorption isotherm closely followed both the Langmuir and Freundlich isothermic models. Variations in solution pH levels demonstrated that with a decrease in the initial solution pH, the adsorption capacity decreases. This is attributed to the leaching of silica and phosphate from the slag to the solution, which imparted a competing effect for adsorption sites. However, with an alkaline pH, such leaching was reduced, and due to formation of calcium carbonate from the leached calcium from the slag material, the arsenic removal efficiency increased as it was co-precipitated with calcium carbonate.

Pre-hospital fibrinolysis in the management of patients with ST elevation acute coronary syndrome: review of the evidence, implementation and future directions

Time to reperfusion is among the strongest predictors of clinical outcome in patients who present with ST elevation acute myocardial infarction. When time to access is equivalent, primary percutaneous coronary intervention has demonstrated superior outcomes to fibrinolysis. However, where significant delays exist in accessing percutaneous intervention, fibrinolysis has an important role. The potential for fibrinolysis delivery in the pre-hospital setting means that delays to primary percutaneous intervention need to be considered from the time that the patient becomes eligible for fibrinolysis in the field. This can be particularly challenging in patients with symptom duration ofless than two hours, as some evidence suggests fibrinolysis may be particularly beneficial in this early phase. Additionally, access to primary percutaneous intervention provided by an experienced operator, in a timely manner at any time of the day or night, is not an available option in many healthcare settings. This review focuses on the current evidence and practice of pre-hospital fibrinolysis and assesses potential roles for this therapy in the future.

Klf5 controls bone marrow homing of stem cells and progenitors through Rab5-mediated β1/β2-integrin trafficking

Kruppel-like factor 5 (Klf5) regulates pluripotent stem cell self-renewal but its role in somatic stem cells is unknown. Here we show that Klf5 deficient haematopoietic stem cells and progenitors (HSC/P) fail to engraft after transplantation. This HSC/P defect is associated with impaired bone marrow homing and lodging and decreased retention in bone marrow, and with decreased adhesion to fibronectin and expression of membrane-bound β1/β2-integrins. In vivo inducible gain-of-function of Klf5 in HSCs increases HSC/P adhesion. The expression of Rab5 family members, mediators of β1/β2-integrin recycling in the early endosome, is decreased in Klf5^Δ/Δ HSC/Ps. Klf5 binds directly to the promoter of Rab5a/b and overexpression of Rab5b rescues the expression of activated β1/β2-integrins, adhesion and bone marrow homing of Klf5^Δ/Δ HSC/Ps. Altogether, these data indicate that Klf5 is indispensable for adhesion, homing, lodging and retention of HSC/Ps in the bone marrow through Rab5-dependent post-translational regulation of β1/β2 integrins.

Optogenetic examination identifies a context-specific role for orexins/hypocretins in anxiety-related behavior

Maladaptation to stress is associated with psychopathology. However, our understanding of the underlying neural circuitry involved in adaptations to stress is limited. Previous work from our lab indicated the paraventricular hypothalamic neuropeptides orexins/hypocretins regulate behavioral and neuroendocrine responses to stress. To further elucidate the role of orexins in adaptation to stress, we employed optogenetic techniques to specifically examine the effects of orexin cell activation on behavior in the social interaction test and in the home cage as well as orexin receptor 1 internalization and ERK phosphorylation in brain regions receiving orexin inputs. In the social interaction test, optogenetic stimulation of orexin neurons decreased time spent in the interaction zone while increasing the frequency of entries into the interaction zone. In addition, optogenetic stimulation of orexin neurons increased the total distance traveled in the social interaction arena but had no effect on their home cage behavior. Together, these results suggest that orexin release increases anxiety in the social interaction test while increasing the salience of novel but not familiar environmental stimuli. Consistent with activation of orexin neurons, optogenetic stimulation increased orexin receptor1 internalization and ERK phosphorylation in the paraventricular thalamus (PVT) and locus coeruleus (LC), two regions heavily innervated by orexin neurons. Together these results show for the first time that elevation of orexin activity, possibly in the PVT and LC, is associated with increased anxiety, activity, and arousal in a context-specific manner.

Comparison study of clinicoradiological profile of primary lung cancer cases: an Eastern India experience

CONTEXT

According to the first population-based cancer registry from eastern part of India, Kolkata and its surrounding areas have the highest prevalence of lung cancer in India. However, there is very limited data from this part of the country.

AIMS

The aim of this study is to find out the demographic and clinicoradiological profile of primary bronchogenic carcinoma.

SETTINGS AND DESIGN

This is a retrospective review of lung cancer cases diagnosed in two tertiary institutes of Kolkata over a period of 4 years.

MATERIALS AND METHODS

We have reviewed the cases with proven histological or cytological diagnosis of primary bronchogenic carcinoma and chi-square test is done to calculate statistical significance.

RESULTS

Out of 607 patients, male 489 and female 118, 67.7% are from rural area, 67.2% are smoker and only 9.4% are ≤40 years of age. Smoking is the major risk factor for primary lung cancer (P = 0.000) but no significance could be established with the different histological subtypes (P = 0.207). Though squamous cell carcinoma (SCC) is the most predominant variety (35.1%), adenocarcinoma and undifferentiated type are overrepresented in ≤40 years. SCC occurs at a significantly higher age group (60.84 ± 12.16 years) than other subtypes (P = 0.000). At least 55.2% cases of nonsmall cell lung cancer and 54% of small cell lung cancer presented in very advanced stage.

CONCLUSIONS

SCC is the most common histological subtype of primary bronchogenic carcinoma. The relatively increased frequency of adenocarcinoma in our study as compared to other studies from India is probably due to higher proportion of nonsmokers.

Putative genes mediating the effects of orexins in the posterior paraventricular thalamus on neuroendocrine and behavioral adaptations to repeated stress

Exposure to repeated stress is often associated with psychopathology. However, our understanding of the underlying neural circuitry that regulates responses to repeated stress is limited. The posterior paraventricular thalamus (pPVT) is a brain region responsible for transmission of multimodal sensory information to limbic structures that regulate responses to both acute and repeated stress. Orexin-containing cells originating in the hypothalamus heavily innervate the pPVT. Our previous work has shown that activation of orexin1 receptors in the pPVT during repeated swim stress is important for facilitation of the hypothalamic-pituitary-adrenal (HPA) axis response to subsequent novel restraint. However, the genes responsible for these orexin-mediated adaptations to repeated stress are not known. Using a custom PCR array we examined the expression of 186 specific mRNAs in the pPVT of animals exposed to repeated swim stress (4 days of 15min swim/day) with or without direct pPVT microinfusion of the orexin1 receptor antagonist SB334867 prior to each daily swim stress. Tissue was collected the next morning under basal non stressed conditions. Repeated stress and/or orexin receptor blockade significantly altered expression of only 9 specific genes including growth factors (Vegfa, Bax and Mt3), G-protein coupled receptors (Adora2a, Grm2 and Crhr1), immune-related genes (Ptgs2 and Cx3cr1) and an epigenetic-related gene (Hdac5). These genes represent potential targets for further characterization of orexin-mediated adaptations to repeated stress in the pPVT.

Estrogen inhibits D2S receptor-regulated Gi3 and Gs protein interactions to stimulate prolactin production and cell proliferation in lactotropic cells

The neurotransmitter dopamine (DA) is known to inhibit prolactin (PRL) secretion and the proliferation of lactotropes in the pituitary gland. Dopamine-2 (D2) receptor short (D2S) isoform is expressed in a reduced level while the D2 receptor long (D2L) isoform is expressed in an elevated level during estradiol (E(2))-induced PRL production and cell proliferation in lactotropes. To evaluate the role of these D2 receptor isoforms in E(2)-regulated lactotropic cell function, we compared E(2) effects on the level of PRL, cell proliferation, and G proteins in enriched lactotropes and lactotrope-derived PR1 cells containing only D2S isoform (D2S cells), D2L isoform (D2L cells), or no D2 receptor (V cells). Additionally, we determined the effects of G protein blockade on the E(2)-induced PRL production and cell proliferation in these cells. We here show that E(2) actions on G proteins, PRL production, and cell proliferation were maximally achieved in D2S cells, oppositely or marginally achieved in D2L cells, and absent in V cells. We also show that the DA and pertussis toxin modulations of E(2) actions on PRL, G proteins, and cell proliferation were maximally achieved in D2S cells compared with in D2L or V cells. Furthermore, we provide evidence for the existence of an inhibitory action of Gi3 on Gs that is under the control of the D2S receptor and is inhibited by E(2). These results suggest that the suppression of D2S-regulated Gi3 inhibition of Gs protein may be one of the mechanisms controlling E(2)-activated PRL synthesis and cell proliferation in lactotropes.

Pulmonary Cavity due to Chronic Eosinophilic Pneumonia Associated with Arsenicosis

In developing country like India arsenic poisoning is a major public health problem. Association of chronic eosinophilic pneumonia and chronic diarrhea with arsenicosis is rare. Also pulmonary cavity formation in chronic eosinophilic pneumonia is very uncommon. A 44-year-old male patient, resident of an arsenic affected area was admitted for evaluation of chronic diarrhoea, persistent peripheral eosinophilia along with radiologically visible cavity in right upper zone. There were dermatological manifestations of arsenicosis along with presence of noncirrhotic portal fibrosis and peripheral eosinophilia. On bronchoalveolar lavage study, eosinophil comprised 40% of total cellularity making the diagnosis of chronic eosinophilic pneumonia. After ruling out all possible causes of diarrhoea and chronic eosinophilic pneumonia, we came to conclusion that arsenic could be implicated as causative agent. Keywords: Arsenicosis, chronic diarrhoea, chronic eosinophilic pneumonia, noncirrhotic portal fibrosis.