The Development of Conductive Nanoporous Chitosan Polymer Membrane for Selective Transport of Charged Molecules

We present the development of conductive nanoporous CNT/chitosan membrane for charge-selective transport of charged molecules, carboxylfluorescein (CF), substance P, and tumor necrosis factor-alpha (TNF-α). The membrane was made porous and conductive via gelatin nanoparticle leaching technique and addition of carbon nanotubes, respectively. These nanoporous membranes discriminate the diffusion of positive-charged molecules while inhibiting the passage of negative-charged molecules as positive potential was applied. The permeation selectivity of these membranes is reversed by converting the polarity of applied potential into negative. Based on this principle, charged molecules (carboxylfluorescein, substance P, and TNF-α) are successfully filtered through these membranes. This system shows 30 times more selective for CF than substance P as positive potential was applied, while 2.5 times more selective for substance P than CF as negative potential was applied

Fabrication and Permeability Characteristics of Microdialysis Probe Using Chitosan Nanoporous Membrane

In this article, a nanoporous chitosan polymer membrane was successfully produced and applied as microdialysis membrane for in vitro sampling of biomolecules. With the use of nanoparticle leaching technique, porogenic gelatin nanoparticles formed nanopores in the chitosan-based membrane to create a secure implantable nanoporous membrane for biomolecule sampling. The gelatin nanoparticles size was in the range of 45 to 70 nm, and the pore size of the chitosan membrane was around 40 to 100 nm. The porosity of membrane was found to be dependent on the mixing ratio of chitosan solution and gelatin nanoparticles solution. The results of diffusion study showed that we can alter the mixing ratio of porogen to achieve size-selective molecular diffusion, which means that the porosity and cut-off size of porous membrane can be controlled. The recoveries of the probe fabricated from the chitosan-based membrane were examined for four different model compounds of different molecular weights: 2-NBDG, substance P, TNF-α, and FITC-BSA. The microdialysis probes showed linear responses and substantial recovery to various concentrations of biomolecules. These results indicated that the microdialysis probe constructed by chitosan nanoporous membrane could sample and monitor the biomolecules in vitro and has the potential for the application in vivo

In vitro intracellular trafficking of biodegradable nanoparticles dextran spermine in cancer cell lines.

The objective of the present study is to evaluate the effect of cationic dextran on the proliferation rate and biosynthetic activities of HT29, a human colonic adenocarcinoma, and MCF7, a human breast cancer cell line. Cationic dextran was prepared by means of reductive-amination between oxidised dextran and the natural oligoamine, spermine. Biological evaluations including cell proliferation assay, and cell cycle were studied. Flow cytometery was performed in order to determine the biological behaviour of cationic dextran after internalised into the cells. Our results clearly indicated that the cationic dextran was not toxic to the cells when the concentration was 5 μg/ml or lower. The results of the cell cycle flow cytometery indicated that the means of R2 in HT29, MCF7 and HeLa cells were less than 5 three days after treatment with 5 μg/ml of cationic dextran. We conclude that the toxicity of cationic dextran is dose dependent and it is not toxic at concentration lower than 5 μg/ml, and tolerable by the cells, and it can be used as a tool for gene delivery

Synchronous right hepatectomy and cesarean section in a pregnant lady with hepatocellular carcinoma

AbstractINTRODUCTIONCancer in pregnancy is rare and hepatocellular carcinoma (HCC) during pregnancy is even rarer. Due to limited experience, management of these patients remains challenging.PRESENTATION OF CASEA 33-year old pregnant lady presented with HCC at 28 weeks of gestation. She underwent synchronous cesarean section and right hepatectomy at 32 weeks of gestation. The post-operative course was uneventful. She was discharged home on day 10 after surgery. Histolopathology confirmed HCC. The surgical resection margins were clear. At a follow-up of 3 months after surgery, the mother was disease free and the infant was well.DISCUSSIONHCC during pregnancy is extremely rare. The experience in its management and outcomes are lacking. In managing any patient diagnosed with a malignant neoplasm in pregnancy, both the mother and the fetus have to be considered.CONCLUSIONWith adequate preoperative assessment and a good management strategy, good results can be obtained for both the mother and the baby for a pregnant patient with HCC

Sex-Specific Correlations of Individual Heterozygosity, Parasite Load, and Scalation Asymmetry in a Sexually Dichromatic Lizard

Heterozygosity-fitness correlations (HFCs) provide insights into the genetic bases of individual fitness variation in natural populations. However, despite decades of study, the biological significance of HFCs is still under debate. In this study, we investigated HFCs in a large population of the sexually dimorphic lizard Takydromus viridipunctatus (Lacertidae). Because of the high prevalence of parasitism from trombiculid mites in this lizard, we expect individual fitness (i.e., survival) to decrease with increasing parasite load. Furthermore, because morphological asymmetry is likely to influence individuals\u27 mobility (i.e., limb asymmetry) and male biting ability during copulation (i.e., head asymmetry) in this species, we also hypothesize that individual fitness should decrease with increasing morphological asymmetry. Although we did not formally test the relationship between morphological asymmetry and fitness in this lizard, we demonstrated that survival decreased with increasing parasite load using a capture-mark-recapture data set. We used a separate sample of 140 lizards to test the correlations between individual heterozygosity (i.e., standardized mean d2 and HL based on 10 microsatellite loci) and the two fitness traits (i.e., parasite load and morphological asymmetry). We also evaluated and excluded the possibility that single-locus effects produced spurious HFCs. Our results suggest male-only, negative correlations between individual heterozygosity and parasite load and between individual heterozygosity and asymmetry, suggesting sex-specific, positive HFCs. Male T. viridipunctatus with higher heterozygosity tend to have lower parasite loads (i.e., higher survival) and lower asymmetry, providing a rare example of HFC in reptiles

Prefrontal activity and heart rate variability during cognitive tasks may show different changes in young and older adults with and without mild cognitive impairment

BackgroundAge-related decline in cognitive function is often linked to changed prefrontal cortex (PFC) activity and heart rate variability (HRV). Mild cognitive impairment (MCI), a transitional stage between normal aging and dementia, might have further degeneration beyond aging. This study aimed to investigate the differences between young and older adults with or without MCI in cognitive functions, task-induced PFC activation and HRV changes.MethodsThirty-one healthy young adults (YA), 44 older adults (OA), and 28 older adults with MCI (OA-MCI) were enrolled and compared in this cross-sectional study. Each participant received a one-time assessment including cognitive and executive functions, as well as the simultaneous recording of PFC activity and HRV during a cognitive task paradigm.ResultsWe observed age-related decrease in global cognitive functions, executive functions, HRV, and increase in PFC activity. The MCI further deteriorated the global cognitive and executive performances, but not the HRV or the prefrontal activation.ConclusionOlder people showed lower performances in general cognitive function and executive function, compensatory increase of PFC activity, and reduced HRV. Older people with MCI had further deterioration in cognitive performance, but not in PFC activation and HRV

Effects of “living high-training low” on male/female obese adolescent’s morphological indices and glucose/lipid metabolism

Abstract Objective:This study aims to investigate the effects of 4 weeks living high-training low (HiLo) on obese adolescent’s body composition, glucose/lipid metabolism and gender differences. Method: 37 overweight and obese adolescents (13-16 old), volunteers participated in the fully closed weight-loss exercises. They were randomly divided into two groups as the normal oxygen group (n=19) and hypoxia group (n=18) and exercised an intervention for four-weeks. For the normal oxygen group, aerobic exercises and diet control intervention methods were used. Exercise intensity and individualized exercise prescription were based upon subject health condition and exercise tolerance test. Dieticians according to subject basal metabolic rate formulated a reasonable diet to ensure the calories and essential nutrient supply. For the hypoxia group, except aerobic exercise and diet control intervention, every night the subjects lived in hypoxic room equipped with hypoxia systems and they were exposed to an altitude of about 2,700 m (10 hours per day) for 4 weeks. Before and after hypoxic exposure, obesity related morphological and blood biochemical indices (blood glucose, blood lipid panel (includes 4 main lipoproteins,etc)) were separately analyzed, calculate homeostasis model assessment was used to estimate insulin resistance (HOMA-IR) and insulin secretion (HOMA-β) index. Results: (1) After hypoxia intervention, morphological indices, immunology indices, blood insulin and blood fat in average significantly decreased in both groups; Moreover blood glucose did not change significantly. In normal oxygen group and hypoxia group ,HOMA-IR and HOMA-β index significantly decreased. (2) Hypoxia combined with exercise and alimentary control have different effects on male/female obese adolescent’s morphological indices and glucose/lipid metabolism that were shown by: 1. Male in hypoxia group showed weight, BMI and body fat significantly decreased more than normal oxygen group, the two groups lean body mass did not change significantly. Moreover, female in hypoxia group showed lean body mass significantly decreased more than normal oxygen group, the two group’s weight, BMI and body fat did not change significantly. 2. Between the two groups, for male subjects HOMA-IR and HOMA-β index did not change significantly; in hypoxia group, for female subjects HOMA-β index decreased, but there was an upward trend in normal oxygen group, the two groups change significantly. Conclusion: (1) The two interventions methods can significantly improve the obese adolescent’s morphological and glucose/lipid metabolism indices. (2) The effects of the two interventions methods on morphological and glucose/lipid metabolism indices are due to gender differences, it should be used selectively based on the current situation