Estimation of phase signal change in neuronal current MRI for evoke response of tactile detection with realistic somatosensory laminar network model

Magnetic field generated by neuronal activity could alter magnetic resonance imaging (MRI) signals but detection of such signal is under debate. Previous researches proposed that magnitude signal change is below current detectable level, but phase signal change (PSC) may be measurable with current MRI systems. Optimal imaging parameters like echo time, voxel size and external field direction, could increase the probability of detection of this small signal change. We simulate a voxel of cortical column to determine effect of such parameters on PSC signal. We extended a laminar network model for somatosensory cortex to find neuronal current in each segment of pyramidal neurons (PN). 60,000 PNs of simulated network were positioned randomly in a voxel. Biot–savart law applied to calculate neuronal magnetic field and additional phase. The procedure repeated for eleven neuronal arrangements in the voxel. PSC signal variation with the echo time and voxel size was assessed. The simulated results show that PSC signal increases with echo time, especially 100/80 ms after stimulus for gradient echo/spin echo sequence. It can be up to 0.1 mrad for echo time = 175 ms and voxel size = 1.48 × 1.48 × 2.18 mm³. With echo time less than 25 ms after stimulus, it was just acquired effects of physiological noise on PSC signal. The absolute value of the signal increased with decrease of voxel size, but its components had complex variation. External field orthogonal to local surface of cortex maximizes the signal. Expected PSC signal for tactile detection in the somatosensory cortex increase with echo time and have no oscillation.     

Hemodynamic and neurohumoral effects of ketanserin, a 5-HT2 receptor antagonist in patients with congestive heart failure

Ketanserin, a recently developed 5-HT2 receptor antagonist, competitively and selectively blocks the vasoconstrictor activity of 5-hydroxytryptamine (serotonin). We explored a possible contribution of serotonin to augmented vascular tone in patients with severe heart failure, using intravenous and oral formulations of ketanserin. When administered intravenously (10 mg bolus, 4 mg/hr infusion for +/- 40 min) to 10 patients with congestive heart failure (NYHA III or IV) secondary to congestive cardiomyopathy (n = 8) or ischemic heart disease (n = 2), the drug produced a significant increase in cardiac output (rest 24%, p less than 0.001; exercise 19%, p less than 0.01) which was accompanied by a fall in systemic arterial pressure (rest 7%, p less than 0.001; exercise 10%, p less than 0.05) and pulmonary wedge (rest 17%, p less than 0.05; exercise 23%, p less than 0.001) pressure. Calculated systemic vascular resistance (SVR, rest 27%, p less than 0.001; exercise 23%, p less than 0.05) decreased significantly. No significant hemodynamic changes were observed when 40 mg of ketanserin was administered orally to the same group of patients. Plasma catecholamines (norepinephrine, NEP:epinephrine, EP:dopamine) were measured before and after ketanserin at rest and during exercise. Baseline NEP levels were markedly elevated at rest and during exercise in all patients (rest: 878 +/- 381 ng/mL, exercise: 1453 +/- 697 ng/mL). Baseline EP levels were within normal limits. Ketanserin did not produce any change in catecholamine concentration.(ABSTRACT TRUNCATED AT 250 WORDS)     

Unhealthy alcohol and drug use is associated with an increased length of stay and hospital cost in patients undergoing major upper gastrointestinal and pancreatic oncologic resections

BackgroundFew studies evaluate the impact of unhealthy alcohol and drug use on the risk and severity of postoperative outcomes after upper gastrointestinal and pancreatic oncologic resections.MethodsThe National Inpatient Sample was queried to identify patients undergoing total gastrectomy, esophagectomy, total pancreatectomy, and pancreaticoduodenectomy between 2012 and 2015. Unhealthy alcohol and drug use was assessed by the International Classification of Diseases, Ninth Revision, and National Inpatient Sample coder designation. Multivariable regression was used to identify associations between alcohol and drug use and postoperative complication, duration of stay, hospital cost, and mortality.ResultsIn the study, 59,490 patients met inclusion criteria; 2,060 (3.5%) had unhealthy alcohol use; 1,265 (2.1%) had unhealthy drug use. Postoperative complication rates were higher in patients with alcohol and drug use than in abstainers (67.5% vs 62.8% vs 57.2%; P < .01). On multivariable regression, alcohol use was independently associated with increased risk of a nonwithdrawal complication (odds ratio 1.33 [1.05, 1.68]), and alcohol and drug use were independently associated with increased length of stay (1.54 [0.12, 2.96]) and 2.22 [0.90, 3.55] days) and cost ($5,471 [$60, $10,881] and $4,022 [$402, $7,643]), but not mortality.ConclusionUnhealthy substance use is associated with increased rates of postoperative complications, prolonged length of stay, and costs in patients undergoing major upper gastrointestinal and pancreatic oncologic resections. Screening and abstinence interventions should be incorporated into the preoperative care pathways for these patients.     

Immunotherapeutic targets in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is one of the most common types of cancer in the world and has a 5-year survival rate of ~20%. Immunotherapies have shown promising results leading to durable responses, however, they are only effective for a subset of patients. To determine the best therapeutic approach, a thorough and in-depth profiling of the tumour microenvironment (TME) is required. The TME is a complex network of cell types that form an interconnected network, promoting tumour cell initiation, growth and dissemination. The stroma, immune cells and endothelial cells that comprise the TME generate a plethora of cytotoxic or cytoprotective signalling pathways. In this review, we discuss immunotherapeutic targets in NSCLC tumours and how the TME may influence patients' response to immunotherapy.     

Hamartoma of the Face

Hamartomas are tumour like malformations which are due to a developmental anomaly. They are most commonly seen in the spleen, lungs, liver and kidney, they are rare in the head and neck region. A rare case of Hamartoma of the soft tissues of the face in a 13 year old boy is reported.     

Holistic Approach to Functional Constipation: Perspective of Traditional Persian Medicine

Traditional Persian medicine (TPM) proposes a different viewpoint to the chronic diseases. Diagnosis and implemented treatment are based on individual differences among patients. Constipation or Ea''teghal-e-batn is a condition in which the patient develops difficult or painful defecation. Based on TPM concepts, the first digestion step starts from halq (oral cavity), and ends via defecation from the maq''ad (anus). Avicenna believed that four faculties, ha''zemeh (digestive), ja''zebeh (absorptive), ma''sekeh (retentive) and da''fe''eh (propulsive), are involved in the process of digestion and absorption of the ingested food and expelling the waste materials. The bowel movement and appearance of the stool is a measure for evaluating the gastrointestinal healthy function. Defecation should be with no pain and fecal material should have no burning and acuity. Low food intake or foods with dry temperament, dryness of gastrointestinal tract, diaphoresis and heavy exercise as well as intestine sensory loss were discussed as main causes of constipation. Management of constipation in TPM includes dietary schemes, oil massages and subsequently simple herbal medicines. According to TPM theories, the first step in treating a disease is the elimination of disease causes (asbab e-maraz) and also providing the causes of health (asbab-e-sehhat). Health care providers should know the proper condition which the herbal medicines should be administered in and be able to guide the patients about the benefits and hazards of herbal remedies, commonly used in their living origin.     

Pseudoangiomatous stromal hyperplasia of the breast: A case report

Pseudoangiomatous stromal hyperplasia (PASH) is a rare benign breast entity scarcely reported in the medical literature. Its pathogenesis, etiology, and optimal treatment are still unknown. PASH tumors have a broad spectrum of clinical presentations and might be mistaken for malignancies. The authors present six patients diagnosed with PASH.     

Introduction of cadmium chloride additive to improve the performance and stability of perovskite solar cells

With the increase in the importance of using green energy sources to meet the world''s energy demands, attempts have been made to push perovskite solar cell technology toward industrialization all around the world. Improving the properties of perovskite materials as the heart of PSCs is one of the methods to fabricate favorable photovoltaic (PV) solar cells based on perovskites. Here, cadmium chloride (CdCl₂) was used as an additive source for the perovskite precursor to improve its PV properties. Results indicated CdCl₂ improves the perovskite growth and tailors its crystalline properties, suggesting boosted charge transport processes in the bulk and interfaces of the perovskite layer with electron–hole transport layers. Overall, by incorporation of 1.0% into the MAPbI₃ layer, a maximum power conversion efficiency of 15.28% was recorded for perovskite-based solar cells, higher than the 12.17% for the control devices. The developed method not only improved the PV performance of devices but also boosted the stability behavior of solar cells due to the passivated domain boundaries and enhanced hydrophobicity in the CdCl₂-based devices.

With the increase in the importance of using green energy sources to meet the world''s energy demands, attempts have been made to push perovskite solar cell technology toward industrialization all around the world.