Ultrafine Electrospun Polyamide‐6 Fibers: Effect of Solution Conditions on Morphology and Average Fiber Diameter

Summary: In the present contribution, the electrostatic spinning or electrospinning technique was used to produce ultra‐fine polyamide‐6 (PA‐6) fibers. The effects of solution conditions on the morphological appearance and the average diameter of as‐spun fibers were investigated by optical scanning (OS) and scanning electron microscopy (SEM) techniques. It was shown that the solution properties (i.e. viscosity, surface tension and conductivity) were important factors characterizing the morphology of the fibers obtained. Among these three properties, solution viscosity was found to have the greatest effect. Solutions with high enough viscosities (viz. solutions at high concentrations) were necessary to produce fibers without beads. At a given concentration, fibers obtained from PA‐6 of higher molecular weights appeared to be larger in diameter, but it was observed that the average diameters of the fibers from PA‐6 of different molecular weights had a common relationship with the solution viscosities which could be approximated by an exponential growth equation. Raising the temperature of the solution during spinning resulted in the reduction of the fiber diameters with higher deposition rate, while mixing m‐cresol with formic acid to serve as a mixed solvent for PA‐6 caused the solutions to have higher viscosities which resulted in larger fiber diameters. Lastly, the addition of some inorganic salts resulted in an increase in the solution conductivity, which caused the fiber diameters to increase due to the large increase in the mass flow.

Average diameter of as‐spun fibers plotted as a function of the viscosity of the solutions.     

Distinct pattern of expression of differentiation and growth-related genes in squamous cell carcinomas of the head and neck revealed by the use of laser capture microdissection and cDNA arrays

Although risk factors for squamous cell carcinomas of the head and neck (HNSCC) are well recognized, very little is known about the molecular mechanisms responsible for this malignancy. Furthermore, the ability to investigate gene expression profiles at different stages of tumor progression is usually limited by the remarkable heterogeneity of these neoplastic lesions. Here, we show the successful use of laser capture microdissection (LCM) to procure specific cell populations. The 5000 cells from representative sets of HNSCC and their matching normal tissues are sufficient to extract RNA of high integrity for the synthesis of labeled amplified cDNA probes which can then be hybridized to these membranes arrayed with known human cancer-related cDNAs. Furthermore, when compared to normal tissues, we demonstrate a consistent decrease in expression of differentiation markers such as cytokeratins, and an increase in the expression of a number of signal transducing and cell cycle regulatory molecules, as well as growth and angiogenic factors and tissue degrading proteases. Unexpectedly, we also found that most HNSCC overexpress members of the wnt and notch growth and differentiation regulatory system, thus suggesting that the wnt and notch pathways may contribute in squamous cell carcinogenesis. This experimental approach may facilitate the identification candidate markers for the early detection of preneoplastic lesions, as well as novel targets for pharmacological intervention in this disease.     

Screening scheme development for active TB prediction among HIV-infected patients

The objective of this study was to develop and evaluate a simple scoring scheme to screen for active tuberculosis (TB) among HIV-infected patients. Two hundred fifty-seven HIV-infected patients were enrolled in the study between April 2009 and May 2010 from Mae Sai District Hospital and Lampang Regional Hospital. Participants underwent routine evaluations to diagnose TB. Data collection included demographics, medical history, signs and symptoms and laboratory results. Of the 257 HIV-infected patients enrolled, 66 (25.7%) were diagnosed with active TB. Six variables were statistically significant predictors of active TB (p < 0.05): BMI < or = 19 kg/m2, cough > 2 weeks, shaking chills > or = 1 week not taking antiretroviral drugs, a CD4+ cell count level < 200 cells/microl, and had a history of TB. A risk score (ranging from 0 to 16) gave a 92.1% sensitivity of being associated with active TB. A low risk score (< or = 2.0), a moderate risk score (3.0-7.0), and a high risk score (>7.0) gave positive likelihood ratios (LHR+) of 0.04 (95% CI 0.01-0.24), 2.56 (95% CI 1.71-3.85), and 11.72 (95% CI 4.91-27.96), respectively. This screening tool may be useful to identify patients who should have further diagnostic testing for TB, but requires further validation before adoption due to the variability of predicting factors and the prevalence of TB in the target population.     

Correlation of Helicobacter pylori and interleukin-8 mRNA expression in high risk gastric cancer population prediction

AIM: To evaluate (1) the association of the Helicobacter pylori (H. pylori) test and interleukin-8 (IL-8) mRNA expression alone and the severity of gastric cancer (GC); (2) the association of both tests were added to patients'' characteristics to identifli Thai suspected patients of gastric cancer who would receive the most benefit; and (3) diagnostic value of levels of IL-8 mRNA expression for gastric cancer.METHODS: A cross-sectional analytical study was completed with 220 patients with 86 GC patients who underwent endoscopy with gastric surgery divided into non-metastasis and metastasis groups, and 134 patients with benign lesions who underwent endoscopic examination, at the Gastrointestinal Surgery and Endoscopy Unit, Chiang Mai University Hospital between 2006 and 2010. Of 220 patients, 86 cases of diagnosed gastric adenocarcinoma were in an advanced stage and 134 cases were non-cancer patients.RESULTS: The IL-8 mRNA expression showed predominant association with advanced GC when compared to H. pylori infection alone [OR (95%CI); 0.86 (0.49-1.53) vs 5.44 (3.08-9.62)] when including the patients’ characteristics the highest of the area under the receiver operating characteristic curves (AuROC) of the model were males older than 40 years of age [AuROC (95%CI); 0.81 (0.75-0.86)]. However, preliminary testing for diagnostic indices of four cut-off points of IL-8 mRNA expression to predict the severity of GC cases found an increasing suboptimal trend from the likelihood ratio of positive to differentiate the severity in the GC group. The IL-8 mRNA expression showed a predominant association with GC when compared to H. pylori infection, especially in males older than 40 years of age who may benefit most from this test.CONCLUSION: The future research of IL-8 mRNA expression to predict severity in the gastric cancer group should be warranted.     

Comparative effectiveness of lactulose and sennosides for the prevention of peritoneal dialysis-related peritonitis: an open-label,randomized, active-controlled trial

BackgroundTo the best of our knowledge, the effectiveness and safety of lactulose in comparison to sennosides, for the prevention of peritoneal dialysis (PD)-related peritonitis, has never been tested in a randomized study.MethodsWe conducted an open-label, randomized, active-controlled trial in a PD-center in Northern Thailand. Adult patients on PD were enrolled and randomly assigned in a 1:1 ratio into two groups; one group received lactulose 15 mL once daily (n = 50) and the other group received sennosides two tablets daily (n = 50). The primary outcome was time-to-first bacterial peritonitis. The secondary outcomes included a composite of bacterial peritonitis and all-cause mortality. Cox proportional hazards regression was calculated and presented as hazard ratios (HRs) with 95% confidence intervals (CIs).ResultsOne hundred PD patients were recruited (50.0% men; mean age 55.5 ± 13.0 years) in this study. The baseline characteristics of the study participants were similar in both groups. No significant trend towards a higher risk of PD-related peritonitis was observed in the lactulose group (HR, 2.32 [95% CI, 0.92–5.83]; p = .051) compared to the sennosides group. Nevertheless, the secondary outcome was significantly higher in the lactulose group (HR, 2.77 [95% CI, 1.20–6.41]; p = .010). The incidence of adverse events was not substantially different between the two groups; however, diarrhoea was more frequent in the lactulose group (38.0% vs. 18.0%; p = .030) than in the sennosides group.ConclusionsTreatment with lactulose is not more effective than sennosides and cannot be routinely recommended for the prevention of peritonitis among the PD population.

TRIAL REGISTRATION

• Thai Clinical Trial Registry (clinicaltrials.in.th); ID: TCTR20171012001

KEY MESSAGE

• To the best of our knowledge, no randomized controlled trial that compares the efficacy and safety profiles of lactulose versus sennosides for the prevention of PD-related peritonitis among the PD population has been conducted.
• In this open-label, randomized, active-controlled trial, treatment with lactulose is not more effective than sennosides in the prevention of PD-related peritonitis, and it could increase the risk of bacterial PD-related peritonitis.
• Further studies with a larger sample size by incorporated real-world evidence are needed to confirm our findings and to explore strategies to prevent peritonitis among PD patients.

     

Cost-effectiveness analysis of cisplatin plus etoposide and carboplatin plus paclitaxel in a phase III randomized trial for non-small cell lung cancer

Aim: Carboplatin plus paclitaxel is a more costly chemotherapy regimen than cisplatin plus etoposide; however there have been reports of higher efficacy and less toxicity of this regimen. Thus, this study aimed to assess the cost‐effectiveness of these two chemotherapy regimens in advanced non‐small cell lung cancer (NSCLC). Methods: Using the perspective of Maharaj Nakorn Chiang Mai Hospital, Thailand, direct medical costs, including chemotherapy, drugs, medical service charges, costs of adverse events, concomitant medication and survival time were directly gathered from 65 patients enrolled from August 2005 to November 2008. A one‐way sensitivity analysis was performed. An incremental cost‐effectiveness ratio (ICER) was also calculated. Results: Of these 65 patients, 30 received cisplatin plus etoposide (Arm I) and 35 received carboplatin plus paclitaxel (Arm II). The median survival time was not statistically significant (8.23 months vs 8.80 months in Arm I and II, respectively; P = 0.99). The total cost per patient in Arm II was about three times that in Arm I (95,548 Baht vs 29,692 Baht) while quality‐adjusted life‐years (QALY) in Arm II were slightly above those in Arm I (0.587 vs 0.412). The ICER was equal to 375,958 Baht per QALY. Conclusion: With a cost‐effectiveness threshold of 100,000 Baht in Thailand, carboplatin plus paclitaxel was still not cost‐effective. While the selection of a suitable regimen for individual patients should not rely on drug and hospital costs alone, the overall cost, including the burden on patients, should be taken into consideration.