Parametric Study of the Flow in the Horizontal Absorber Tube of the Parabolic Trough Collector

The inability of base fluid to carry a sufficient amount of thermal energy to the storage system or power block has encouraged researchers to improve the performance of base fluid by adding particles suspended in the base fluid to improve the thermal properties of the resulting fluid (nanofluid). Besides, several options can be used for improving heat transfer associated with internal flow inside a solar receiver. This augmentation in convection heat transfer can be obtained by increasing the convection heat transfer coefficient and /or by increasing the convection surface area. Inducing swirl by twisted tape inside the receiver enhances the convection heat transfer coefficient. In this paper, an indoor test rig has been designed and manufactured for this purpose. A measuring technique has been implemented and executed for measuring all parameters regarding heat transfer and fluid flow to simulate the outdoor test rig of the parabolic trough absorbing tube. The measuring technique shows that the error is less than 1 percentage, In addition, nonuniform heattemperature distribution has been measured

Clinical applications of neurostimulation: forty years later

Abstract: With the recent technological advances, neurostimulation has provided new hope for millions of patients with debilitating chronic pain conditions that respond poorly to other therapies. Outcome research demonstrated that patients with failed back surgery syndrome and complex regional pain syndromes benefit significantly from neurostimulation in pain reduction, functional capacity, and quality of life. Increasing clinical evidence supports the use of neurostimulation in post-herpetic neuralgia, peripheral neuropathy, occipital neuralgia, and other neuropathic pain conditions. Strong clinical evidences indicate that neurostimulation offers less invasive and more effective therapies for many patients with ischemic pain caused by cardiovascular and peripheral vascular diseases. A growing body of literature supports neurostimulation for visceral pain in general and interstitial cystitis in particular. As a basic principle, patient selection for the appropriate neurostimulation modalities is essential for safe, efficacious, and costeffective applications of this therapy. Research with more vigorous designs is needed to establish evidence-based applications of neuromodulation therapy in emerging indications of pain management

Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

Advancements in Skin Aging Treatment: Exploring Antioxidants and Nanoparticles for Enhanced Skin Permeation

Many people have always aspired to have skin that is young-looking and vibrant. The natural aging process of the skin, which is impacted by both internal and external factors, has sparked further research into its origins and the creation of efficient therapeutic approaches. This review aims to give a thorough understanding of the skin's composition, the causes and variables that contribute to skin aging, the difficulties in treating skin aging, and the methods used to treat skin aging. It will also go into detail about the obstacles antioxidants face while trying to permeate the skin and their potential role as essential players in the fight against skin aging. In addition, it will discuss the intriguing use of nanoparticles (NPs) in reversing skin aging, emphasizing their involvement in enhanced skin penetration. Due to their distinct size-dependent characteristics and ability to integrate medicines, NPs in general provide a variety of therapeutic benefits for antioxidant drug delivery to control skin aging

Brief Report: Safety and Antitumor Activity of Alectinib Plus Atezolizumab From a Phase 1b Study in Advanced ALK-Positive NSCLC

INTRODUCTION: Alectinib is a preferred first-line treatment option for advanced ALK-positive NSCLC. Combination regimens of alectinib with immune checkpoint inhibitors are being evaluated for synergistic effects. METHODS: Adults with treatment-naive, stage IIIB/IV, or recurrent ALK-positive NSCLC were enrolled into a two-stage phase 1b study. Patients received alectinib 600 mg (twice daily during cycle 1 and throughout each 21-d cycle thereafter) plus atezolizumab 1200 mg (d8 of cycle 1 and then d1 of each 21-d cycle). Primary objectives were to evaluate safety and tolerability of alectinib plus atezolizumab. Secondary objectives included assessments of antitumor activity. RESULTS: In total, 21 patients received more than or equal to 1 dose of alectinib or atezolizumab. As no dose-limiting toxicities were observed in stage 1 (n = 7), the starting dose and schedule were continued into stage 2 (n = 14). Median duration of follow-up was 29 months (range: 1-39). Grade 3 treatment-related adverse events occurred in 57% of the patients, most often rash (19%). No grade 4 or 5 treatment-related adverse events were reported. Confirmed objective response rate was 86% (18 of 21; 95% confidence interval [CI]: 64-97). Median progression-free survival was not estimable (NE) (95% CI: 13 mo-NE), neither was median overall survival (95% CI: 33 mo-NE). CONCLUSIONS: The combination of alectinib and atezolizumab is feasible, but increased toxicity was found compared with the individual agents. With small sample sizes and relatively short follow-up, definitive conclusions regarding antitumor activity cannot be made

Durability of Supplemental Nucleus Pulposus Allograft in Patients with Lumbar Discogenic Pain

Shrif Costandi,1 Douglas P Beall,2 Timothy T Davis,3 Kasra Amirdelfan,4 Ramana K Naidu,5 Michael J DePalma,6 Edward S Yoon,7 Jacob W Fleming,8 Jon E Block,9 Nagy Mekhail1 1Pain Management, Cleveland Clinic, Cleveland, OH, USA; 2Comprehensive Specialty Care, Edmond, OK, USA; 3Source Healthcare, Santa Monica, CA, USA; 4Boomerang Healthcare, Inc., Walnut Creek, CA, USA; 5MarinHealth Spine Institute, Larkspur, CA, USA; 6Virginia iSpine Physicians, Richmond, VA, USA; 7Interventional Radiology, Hospital for Special Surgery, New York, NY, USA; 8Vascular and Interventional Specialists, Dallas, TX, USA; 9Private Practice, San Francisco, CA, USACorrespondence: Jon E Block, Private Practice, 2210 Jackson Street, Ste. 401, San Francisco, CA, 94115, USA, Tel +1 415-775-7947, Email [email protected]: The objective of this study was to determine the degree of improvement in lumbar discogenic pain severity and associated back impairment in patients with chronic axial low back pain treated with intradiscally delivered allogeneic nucleus pulposus (NP) at up to two vertebral levels (L1-S1).Methods: Prospective, single-arm clinical study conducted at 6 sites in the US involving 28 participants with discogenic pain (mean age: 44 ± 13 yrs) and modified Pfirrmann grade 3– 7 on magnetic resonance imaging. This report includes the final participant follow up at 24 months post procedure. Back pain severity was evaluated using an 11-point numeric rating scale (NRS) and back function using the Oswestry Disability Index (ODI). Minimal clinically important difference (MCID) and substantial clinical benefit (SCB) were set at ≥ 30% and ≥ 50% over baseline, respectively. The patient acceptable symptom state (PASS) threshold for pain severity was ≤ 3.Results: The average improvement in back pain severity from 7.1 ± 1.6 at baseline to 3.6 ± 2.9 at 24 months was 43% (p< 0.001). Approximately 64% (14 of 22) of participants achieved both the MCID and SCB in back pain at 24 months, while nearly 55% (12 of 22) reported a 24-month back pain severity score of ≤ 3. The corresponding average decrease in ODI values was 53% (p< 0.001) with 73% (16 of 22) of participants achieving the MCID. At baseline approximately 82% (23 of 28) of participants reported severe or crippled back impairment compared to 18% (4 of 22) at 24 months (p< 0.001). There was no association between modified Pfirrmann grade, number of levels treated or Modic changes and any outcome (range: p=0.12 to 0.43).Conclusion: This study provides evidence of clinically significant pain relief and functional improvement through 24 months of follow up after a single allogeneic NP supplementation procedure in patients with lumbar discogenic pain.Keywords: nucleus pulposus, allograft, discogenic, back pain, intradiscal, degenerative disc diseas

Small Vessel Ischemic Disease of the Brain and Brain Metastases in Lung Cancer Patients

Brain metastases occur commonly in patients with lung cancer. Small vessel ischemic disease is frequently found when imaging the brain to detect metastases. We aimed to determine if the presence of small vessel ischemic disease (SVID) of the brain is protective against the development of brain metastases in lung cancer patients.A retrospective cohort of 523 patients with biopsy confirmed lung cancer who had received magnetic resonance imaging of the brain as part of their standard initial staging evaluation was reviewed. Information collected included demographics, comorbidities, details of the lung cancer, and the presence of SVID of the brain. A portion of the cohort had the degree of SVID graded. The primary outcome measure was the portion of study subjects with and without SVID of the brain who had evidence of brain metastases at the time of initial staging of their lung cancer.109 patients (20.8%) had evidence of brain metastases at presentation and 345 (66.0%) had evidence of SVID. 13.9% of those with SVID and 34.3% of those without SVID presented with brain metastases (p<0.0001). In a model including age, diabetes mellitus, hypertension, hyperlipidemia, and tobacco use, SVID of the brain was found to be the only protective factor against the development of brain metastases, with an OR of 0.31 (0.20, 0.48; p<0.001). The grade of SVID was higher in those without brain metastases.These findings suggest that vascular changes in the brain are protective against the development of brain metastases in lung cancer patients

Ex Vivo Activity of Cardiac Glycosides in Acute Leukaemia

BACKGROUND: Despite years of interest in the anti-cancerous effects of cardiac glycosides (CGs), and numerous studies in vitro and in animals, it has not yet been possible to utilize this potential clinically. Reports have demonstrated promising in vitro effects on different targets as well as a possible therapeutic index/selectivity in vitro and in experimental animals. Recently, however, general inhibition of protein synthesis was suggested as the main mechanism of the anti-cancerous effects of CGs. In addition, evidence of species differences of a magnitude sufficient to explain the results of many studies called for reconsideration of earlier results. PRINCIPAL FINDINGS: In this report we identified primary B-precursor and T-ALL cells as being particularly susceptible to the cytotoxic effects of CGs. Digitoxin appeared most potent and IC(50) values for several patient samples were at concentrations that may be achieved in the clinic. Significant protein synthesis inhibition at concentrations corresponding to IC(50) was demonstrated in colorectal tumour cell lines moderately resistant to the cytotoxic effects of digoxin and digitoxin, but not in highly sensitive leukaemia cell lines. CONCLUSION: It is suggested that further investigation regarding CGs may be focused on diagnoses like T- and B-precursor ALL

Long-term survival in patients with non-small cell lung cancer and synchronous brain metastasis treated with whole-brain radiotherapy and thoracic chemoradiation

<p>Abstract</p> <p>Background</p> <p>Brain metastases occur in 30-50% of Non-small cell lung cancer (NSCLC) patients and confer a worse prognosis and quality of life. These patients are usually treated with Whole-brain radiotherapy (WBRT) followed by systemic therapy. Few studies have evaluated the role of chemoradiotherapy to the primary tumor after WBRT as definitive treatment in the management of these patients.</p> <p>Methods</p> <p>We reviewed the outcome of 30 patients with primary NSCLC and brain metastasis at diagnosis without evidence of other metastatic sites. Patients were treated with WBRT and after induction chemotherapy with paclitaxel and cisplatin for two cycles. In the absence of progression, concurrent chemoradiotherapy for the primary tumor with weekly paclitaxel and carboplatin was indicated, with a total effective dose of 60 Gy. If disease progression was ruled out, four chemotherapy cycles followed.</p> <p>Results</p> <p>Median Progression-free survival (PFS) and Overall survival (OS) were 8.43 ± 1.5 and 31.8 ± 15.8 months, respectively. PFS was 39.5% at 1 year and 24.7% at 2 years. The 1- and 2-year OS rates were 71.1 and 60.2%, respectively. Three-year OS was significantly superior for patients with N0-N1 stage disease vs. N2-N3 (60 vs. 24%, respectively; Response rate [RR], 0.03; <it>p</it>= 0.038).</p> <p>Conclusions</p> <p>Patients with NSCLC and brain metastasis might benefit from treatment with WBRT and concurrent thoracic chemoradiotherapy. The subgroup of N0-N1 patients appears to achieve the greatest benefit. The result of this study warrants a prospective trial to confirm the benefit of this treatment.</p

HEX expression and localization in normal mammary gland and breast carcinoma

BACKGROUND: The homeobox gene HEX is expressed in several cell types during different phases of animal development. It encodes for a protein localized in both the nucleus and the cytoplasm. During early mouse development, HEX is expressed in the primitive endoderm of blastocyst. Later, HEX is expressed in developing thyroid, liver, lung, as well as in haematopoietic progenitors and endothelial cells. Absence of nuclear expression has been observed during neoplastic transformation of the thyroid follicular cells. Aim of the present study was to evaluate the localization and the function of the protein HEX in normal and tumoral breast tissues and in breast cancer cell lines. METHODS: HEX expression and nuclear localization were investigated by immunohistochemistry in normal and cancerous breast tissue, as well as in breast cancer cell lines. HEX mRNA levels were evaluated by real-time PCR. Effects of HEX expression on Sodium Iodide Symporter (NIS) gene promoter activity was investigated by HeLa cell transfection. RESULTS: In normal breast HEX was detected both in the nucleus and in the cytoplasm. In both ductal and lobular breast carcinomas, a great reduction of nuclear HEX was observed. In several cells from normal breast tissue as well as in MCF-7 and T47D cell line, HEX was observed in the nucleolus. MCF-7 treatment with all-trans retinoic acid enhanced HEX expression and induced a diffuse nuclear localization. Enhanced HEX expression and diffuse nuclear localization were also obtained when MCF-7 cells were treated with inhibitors of histone deacetylases such as sodium butyrate and trichostatin A. With respect to normal non-lactating breast, the amount of nuclear HEX was greatly increased in lactating tissue. Transfection experiments demonstrated that HEX is able to up-regulate the activity of NIS promoter. CONCLUSION: Our data indicate that localization of HEX is regulated in epithelial breast cells. Since modification of localization occurs during lactation and tumorigenesis, we suggest that HEX may play a role in differentiation of the epithelial breast cell