Procoagulant and Antimicrobial Effects of Chitosan in Wound Healing.

Chitosan, a polysaccharide derived from chitin, has excellent wound healing properties, including intrinsic antimicrobial and hemostatic activities. This study investigated the effectiveness of chitosan dressing and compared it with that of regular gauze dressing in controlling clinically surgical bleeding wounds and profiled the community structure of the microbiota affected by these treatments. The dressings were evaluated based on biocompatibility, blood coagulation factors in rat, as well as antimicrobial and procoagulant activities, and the microbial phylogenetic profile in patients with abdominal surgical wounds. The chitosan dressing exhibited a uniformly fibrous morphology with a large surface area and good biocompatibility. Compared to regular gauze dressing, the chitosan dressing accelerated platelet aggregation, indicated by the lower ratio of prothrombin time and activated partial thromboplastin time, and had outstanding blood absorption ability. Adenosine triphosphate assay results revealed that the chitosan dressing inhibited bacterial growth up to 8 d post-surgery. Moreover, 16S rRNA-based sequencing revealed that the chitosan dressing effectively protected the wound from microbial infection and promoted the growth of probiotic microbes, thereby improving skin immunity and promoting wound healing. Our findings suggest that chitosan dressing is an effective antimicrobial and procoagulant and promotes wound repair by providing a suitable environment for beneficial microbiota.

Activities of Ca2+-related ion channels during the formation of kidney stones in an infection-induced urolithiasis rat model.

Bacterial infection has long been recognized to contribute to struvite urinary stone deposition; however, its contribution to the development of chronic kidney stones has not been extensively investigated. In the present study, we hypothesized another possible method of bacteria contributing to the formation of calcium oxalate (CaOx) that accounts for the biggest part of the kidney stone. Bacteria may play important roles by influencing renal Ca2+-related ion channel activities, resulting in chronic inflammation of the kidney along with rapid aggregation of stones. We examined the correlation among infection-promoted CaOx kidney stones and alterations in Ca2+-related ion channels in an animal model with experimentally induced Proteus mirabilis and foreign body infection. After the bladder was infected for 7 days, the data demonstrated that stones were presented and induced severe renal tubular breakage as well as altered levels of monocyte chemoattractant protein-1, cyclooxygenase-2, osteopontin, and transient receptor potential vanilloid member 5 expression, reflecting responses of kidney ion channels. Monocyte chemoattractant protein-1, osteopontin, and transient receptor potential vanilloid member 5 expression was significantly downregulated over time, indicating the chronic inflammation phase of the kidney and accelerated aggregation of CaOx crystals, respectively, whereas cyclooxygenase-2 exhibited no differences. These results indicated that bacterial infection is considerably correlated with an alteration in renal Ca2+-related ion channels and might support specific and targeted Ca2+-related ion channel-based therapeutics for urolithiasis and related inflammatory renal damage.

Estimation of the disposition index based on components of metabolic syndrome.

Decreased insulin sensitivity (IS) and impaired insulin secretion are major pathological features of type 2 diabetes (T2DM). The product of these factors is the disposition index (DI). We aimed to develop an equation for predicting DI. We enrolled 167 participants in our study. We randomly assigned 126 (75%) of the participants to the study group, whose data would be used to build the equation for estimating the DI. The remaining 41 participants comprised the external validation group. A frequently sampled intravenous glucose-tolerance test was performed for all participants, and the IS, the glucose sensitivity, the acute insulin response to the glucose load, and the DI were determined. Three factors were selected from multiple linear regression analysis, and we constructed the equation log (DI) = 2.449 - 0.113 × fasting plasma glucose + 0.046 × body mass index - 0.612 × high-density lipoprotein cholesterol. Using this equation, the calculated log (DI) significantly correlated with the measured log (DI) in the external validation group (r = 0.428, p = 0.007). By using the equation based on the demographic data and measurements of metabolic syndrome components, the DI could be predicted with acceptable accuracy (r = 0.428). Because of the relationships between the MetS and demographic parameters, this method of predicting DI may help further clinicians' understanding of the underlying pathological mechanisms in T2DM.

The Mediating Role of Psychological Well-Being in the Relationship Between Self-Management and Quality of Life in Patients With Hypertension.

This study applied a cross-sectional design to examine the relationship between self-management, psychological well-being, and quality of life in patients with hypertension and evaluated the mediation effect of psychological well-being on self-management and quality of life. Through purposive sampling, this study enrolled 255 patients with hypertension from the cardiology department of a teaching hospital in Taiwan. Mediation effects were estimated using linear regression and the Sobel test. Age, number of chronic diseases, waist circumference, self-management, and psychological well-being explained 18.7% of the total variance in quality of life. Psychological well-being partially mediated the effects of self-management on quality of life, with a total effect of 19.2%. Psychological well-being is an important factor correlated with self-management and quality of life in patients with hypertension.

Serum bone resorption markers after parathyroidectomy for renal hyperparathyroidism: correlation analyses for the cross-linked N-telopeptide of collagen I and tartrate-resistant acid phosphatase.

Patients on long-term dialysis may develop secondary hyperparathyroidism (SHPT) with increased serum concentrations of bone resorption markers such as the cross-linked N-telopeptide of type I collagen (NTX) and type-5b tartrate-resistant acid phosphatase (TRAP). When SHPT proves refractory to treatment, parathyroidectomy (PTX) may be needed. Renal patients on maintenance HD who received PTX for refractory SHPT (n = 23) or who did not develop refractory SHPT (control subjects; n = 25) were followed prospectively for 4 weeks. Serum intact parathyroid hormone (iPTH), NTX, TRAP, and bone alkaline phosphatase (BAP) concentrations were measured serially and correlation analyses were performed. iPTH values decreased rapidly and dramatically. BAP values increased progressively with peak increases observed at 2 weeks after surgery. NTX and TRAP values decreased concurrently and progressively through 4 weeks following PTX. A significant correlation between TRAP and NTX values was observed before PTX but not at 4 weeks after PTX. Additionally, the fractional changes in serum TRAP were larger than those in serum NTX at all times examined after PTX. Serum iPTH, TRAP, and NTX values declined rapidly following PTX for SHPT. Serum TRAP values declined to greater degrees than serum NTX values throughout the 4-week period following PTX.

Effects of repetitive hyperbaric oxygen treatment in patients with acute cerebral infarction: a pilot study.

The role of hyperbaric oxygen therapy (HBOT) in the treatment of acute ischemic stroke is controversial. This prospective study assessed the efficacy and safety of HBOT as adjuvant treatment on 46 acute ischemic stroke in patients who did not receive thrombolytic therapy. The HBOT group (n = 16) received conventional medical treatment with 10 sessions of adjunctive HBOT within 3-5 days after stroke onset, while the control group (n = 30) received the same treatment but without HBOT. Early (around two weeks after onset) and late (one month after onset) outcomes (National Institutes of Health Stroke Scale, NIHSS scores) and efficacy (changes of NIHSS scores) of HBOT were evaluated. The baseline clinical characteristics were similar in both groups. Both early and late outcomes of the HBOT group showed significant difference (P ≤ 0.001). In the control group, there was only significant difference in early outcome (P = 0.004). For early efficacy, there was no difference when comparing changes of NIHSS scores between the two groups (P = 0.140) but there was statistically significant difference when comparing changes of NIHSS scores at one month (P ≤ 0.001). The HBOT used in this study may be effective for patients with acute ischemic stroke and is a safe and harmless adjunctive treatment.

[Biomarkers in heart failure: BNP and NT-proBNP].

Used as biomarkers of heart failure (HF), BNP and NT-proBNP may be considered as the 'fatal finish line' for all cardiovascular disorders. The incidence of heart failure has increased steadily over the past several decades. High readmission rates for patients with acute decompensated heart failure have led to a search for biomarkers able to predict future clinical outcomes that would facilitate HF patient monitoring and help guide therapy. Molecular biomarkers play an important role in heart failure. From among several promising markers, the family of natriuretic peptides, especially B-type natriuretic peptide (BNP) and NT-proBNP, have been identified as potentially valuable diagnostic and prognostic tools. Not unexpectedly, BNP/NT-proBNP fails to fulfill all the criteria of an ideal biomarker. The development of additional biomarkers will be an important step toward improving diagnosis and treatment of patients with chronic and acute decompensated heart failure.

Biological Effects of Chitosan-Based Dressing on Hemostasis Mechanism.

There have been numerous recent advances in wound care management. Nevertheless, the assessment of hemostatic dressing is essential to enable surgeons and other physicians and healthcare professionals to make the correct decisions regarding the disposition of severe hemorrhage. Here, we investigated the relative efficacies of chitosan-based and conventional gauze dressings in a rat model of femoral artery hemorrhage and in patients with surgical wounds. Dressing effectiveness was evaluated based on hemostatic profiles, biocompatibility, antimicrobial activity, and blood factor responses in coagulation. Relative to standard gauze dressing, the chitosan fiber (CF) dressing treatment significantly shortened the time to hemostasis in injured rats. Moreover, the CF dressing significantly prolonged partial thromboplastin time, enhanced blood absorption, and reduced antithrombin production without altering the prothrombin ratio. Unlike regular gauze bandages, the CF dressing demonstrated remarkable antibacterial activity. The results of this study indicate the effectiveness of chitosan as a hemostatic dressing and elucidate its underlying mechanism. It is possible that chitosan surgical dressings could serve as first-line intervention in hospital emergency care for uncontrolled hemorrhage.

Evaluation of Chitosan-based Dressings in a Swine Model of Artery-Injury-Related Shock.

Uncontrolled haemorrhage shock is the highest treatment priority for military trauma surgeons. Injuries to the torso area remain the greatest treatment challenge, since external dressings and compression cannot be used here. Bleeding control strategies may thus offer more effective haemostatic management in these cases. Chitosan, a linear polysaccharide derived from chitin, has been considered as an ideal material for bleeding arrest. This study evaluated the potential of chitosan-based dressings relative to commercial gauze to minimise femoral artery haemorrhage in a swine model. Stable haemostasis was achieved in animals treated with chitosan fibre (CF) or chitosan sponge (CS), resulting in stabilisation of mean arterial pressure and a substantially higher survival rate (100% vs. 0% for gauze). Pigs receiving treatment with CF or CS dressings achieved haemostasis within 3.25 ± 1.26 or 2.67 ± 0.58 min, respectively, significantly more rapidly than with commercial gauze (>100 min). Moreover, the survival of animals treated with chitosan-based dressings was dramatically prolonged (>180 min) relative to controls (60.92 ± 0.69 min). In summary, chitosan-based dressings may be suitable first-line treatments for uncontrolled haemorrhage on the battlefield, and require further investigation into their use as alternatives to traditional dressings in prehospital emergency care.

Bioapplications of Bacterial Cellulose Polymers Conjugated with Resveratrol for Epithelial Defect Regeneration.

Excellent wound dressing is essential for effective wound repair and regeneration. However, natural polymeric skin substitutes often lack mechanical strength and hydrophilicity. One way to overcome this limitation is to use biodegradable polymers with high mechanical strength and low skin-irritation induction in wet environments. Bacterial cellulose (BC) is an attractive polymer for medical applications; unlike synthetic polymers, it is biodegradable and renewable and has a strong affinity for materials containing hydroxyl groups. Therefore, we conjugated it with resveratrol (RSV), which has a 4'-hydroxyl group and exhibits good biocompatibility and no cytotoxicity. We synthesized BC scaffolds with immobilized RSV and characterized the resulting BC/RSV scaffold with scanning electron microscopy and Fourier-transform infrared spectroscopy. We found that RSV was released from the BC in vitro after ~10 min, and immunofluorescence staining showed that BC was highly biocompatible and regenerated epithelia. Additionally, Masson's trichrome staining showed that the scaffolds preserved the normal collagen-bundling pattern and induced re-epithelialization in defective rat epidermis. These results indicated that RSV-conjugated BC created a biocompatible environment for stem cell attachment and growth and promoted epithelial regeneration during wound healing.

Psychometric evaluation of the Chinese version of the Minnesota Living with Heart Failure Questionnaire.

BACKGROUND: Health-related quality of life has emerged as an important outcome in treating and managing patients with heart failure (HF). However, there is no existing instrument for use in Chinese populations. OBJECTIVES: To translate the Minnesota Living With Heart Failure Questionnaire (MLHFQ) into a Chinese version and to validate it in the clinical setting. METHODS: This was a cross-sectional study. A convenience sample of 247 participants with New York Heart Association Class II to III chronic HF were recruited from a cardiovascular outpatient department in Taiwan. RESULTS: The content validity index was 0.98. Construct validity was supported by exploratory factor analysis, which showed three factors with 20 of 21 items loading above .50, explaining 71% of the variance. Total scale and subscale scores were correlated highly with the reference instruments, indicating satisfactory concurrent and convergent validity. The mean scores of the Chinese version of the MLHFQ were significantly higher among participants with HF than those from a non-HF comparison group. The instrument demonstrated high internal consistency (Cronbach's alpha of .95 for the scale and .93 to .95 for the subscales). CONCLUSION: The psychometric properties indicate that the Chinese version of the MLHFQ is a valid and reliable instrument for future research. This instrument provides a holistic approach for measuring health-related quality of life in New York Heart Association Class II and III HF patients.

Intradialytic aerobic cycling exercise alleviates inflammation and improves endothelial progenitor cell count and bone density in hemodialysis patients.

Inflammation, endothelial dysfunction, and mineral bone disease are critical factors contributing to morbidity and mortality in hemodialysis (HD) patients. Physical exercise alleviates inflammation and increases bone density. Here, we investigated the effects of intradialytic aerobic cycling exercise on HD patients. Forty end-stage renal disease patients undergoing HD were randomly assigned to either an exercise or control group. The patients in the exercise group performed a cycling program consisting of a 5-minute warm-up, 20 minutes of cycling at the desired workload, and a 5-minute cool down during 3 HD sessions per week for 3 months. Biochemical markers, inflammatory cytokines, nutritional status, the serum endothelial progenitor cell (EPC) count, bone mineral density, and functional capacity were analyzed. After 3 months of exercise, the patients in the exercise group showed significant improvements in serum albumin levels, the body mass index, inflammatory cytokine levels, and the number of cells positive for CD133, CD34, and kinase insert domain-conjugating receptor. Compared with the exercise group, the patients in the control group showed a loss of bone density at the femoral neck and no increases in EPCs. The patients in the exercise group also had a significantly greater 6-minute walk distance after completing the exercise program. Furthermore, the number of EPCs significantly correlated with the 6-minute walk distance both before and after the 3-month program. Intradialytic aerobic cycling exercise programs can effectively alleviate inflammation and improve nutrition, bone mineral density, and exercise tolerance in HD patients.

Identification of insulin resistance in subjects with normal glucose tolerance.

INTRODUCTION: Decreased insulin action (insulin resistance) is crucial in the pathogenesis of type 2 diabetes. Decreased insulin action can even be found in normoglycaemic patients, and they still bear increased risks for cardiovascular disease. In this study, we built models using data from metabolic syndrome (Mets) components and the oral glucose tolerance test (OGTT) to detect insulin resistance in subjects with normal glucose tolerance (NGT). MATERIALS AND METHODS: In total, 292 participants with NGT were enrolled. Both an insulin suppression test (IST) and a 75-g OGTT were administered. The steady-state plasma glucose (SSPG) level derived from the IST was the measurement of insulin action. Participants in the highest tertile were defined as insulin-resistant. Five models were built: (i) Model 0: body mass index (BMI); (ii) Model 1: BMI, systolic and diastolic blood pressure, triglyceride; (iii) Model 2: Model 1 + fasting plasma insulin (FPI); (iv) Model 3: Model 2 + plasma glucose level at 120 minutes of the OGTT; and (v) Model 4: Model 3 + plasma insulin level at 120 min of the OGTT. RESULTS: The area under the receiver operating characteristic curve (aROC curve) was observed to determine the predictive power of these models. BMI demonstrated the greatest aROC curve (71.6%) of Mets components. The aROC curves of Models 2, 3, and 4 were all substantially greater than that of BMI (77.1%, 80.1%, and 85.1%, respectively). CONCLUSION: A prediction equation using Mets components and FPI can be used to predict insulin resistance in a Chinese population with NGT. Further research is required to test the utility of the equation in other populations and its prediction of cardiovascular disease or diabetes mellitus.

Relationships between alanine aminotransferase levels, abnormal liver echogenicity, and metabolic syndrome.

BACKGROUND: Elevated alanine aminotransferase (e-ALT) and abnormal liver echogenicity (ab-echo), as determined by sonography, have been linked to metabolic syndrome (MetS). However, which of these is more closely related to MetS, especially among older men, remains unknown. METHODS: Data from 3065 men aged 65 years or older who were undergoing a routine health examination and who were not taking any medications for MetS were analyzed retrospectively. The patients were divided into 4 groups: group N (n= 1228; patients have normal ALT and liver echogenicity); group A (n=110; patients have e-ALT but normal liver echogenicity); group E (n=1381; patients have ab-echo but normal ALT); group AE (n=346; patients have both e-ALT and ab-echo). RESULTS: Among the 3065 subjects, 714 participants were found to have MetS (23.3%). It is not surprising that MetS components were highest in group AE. More interestingly, compared with group A, group E had higher levels of MetS components (except that high-density lipoprotein cholesterol levels were lower). Similar findings were confirmed by logistic regression. Group E had a significantly higher odds ratio of having MetS than group A (2.73; 95% CI, 1.565-4.763). CONCLUSIONS: Our data confirm that both e-ALT and ab-echo are related to a higher incidence of MetS among Taiwanese older men. Of these 2 abnormalities, ab-echo seems to be more closely related to MetS. Further studies are needed to elucidate the complex relationships between these factors in other age and ethnic groups.