A feasibility study on using smartphones to conduct short-version verbal autopsies in rural China.

BACKGROUND: Currently there are two main sources of mortality data with cause of death assignments in China. Both sources-the Ministry of Health-Vital Registration system and the Chinese Disease Surveillance Point system-present their own challenges. A new approach to cause of death assignment is a smartphone-based shortened version of a verbal autopsy survey. This study evaluates the feasibility and acceptability of this new method conducted by township health care providers (THP) and village doctors (VD) in rural China, where a large proportion of deaths occur in homes and cause of death data are inaccurate or lacking. METHODS: The Population Health Metrics Research Consortium mobile phone-based shortened verbal autopsy questionnaire was made available on an Android system-based application, and cause of death was derived using the Tariff method (Tariff 2.0); we called this set of tools "msVA." msVA was administered to relatives of the deceased by six THPs and six VDs in 24 villages located in six townships of Luquan County, Hebei Province, China. Subsequently, interviews were conducted among 12 interviewers, 12 randomly selected respondents, and five study staff to assess the feasibility and acceptability of using msVA for mortality data collection. RESULTS: Between July 2013 and August 2013, 268 deaths took place in the study villages. Among the 268 deaths, 227 VAs were completed (nine refusals, 31 migrations and one loss of data due to breakdown of the smartphone). The average time for a VA interview was 21.5 ± 3.4 min (20.1 ± 3.5 min for THP and 23.2 ± 4.1 min for VD). Both THPs and VDs could be successful interviewers; the latter needed more training but had more willingness to implement msVA in the future. The interviews revealed that both interviewers and relatives of the deceased found msVA to be feasible, acceptable, and more desirable than traditional methods. The cost of conducting a new VA was $8.87 per death. CONCLUSIONS: Conduction of msVA by VDs in their own villages was feasible and acceptable in rural northern China. Broader implementation of msVA across rural China could potentially improve the coverage and quality of cause of death data, allowing for better national health evaluation and program planning.

[Studies on optimizing extraction technics of flowers of Polygonum orientale by response surface methodology].

OBJECTIVE: To analyze and optimize extraction technics of Polygonum orientale flowers by response surface methodology. METHODS: With the index for the content of taxifolin in flowers of Polygonum orientale, the effect of three factors such as concentration of alcohol, extraction time and solvent-solid ratio was designed by Box-Behnken central composite. Extraction technic parameters of Polygonum orientale flowers was optimized by response surface methodology. RESULTS: The optimizing extraction conditions of Polygonum orientale flowers were as follows: ethanol concentration was 65%, extracting time was 129 min and solvent-solid ratio was 18. Under the conditions, the average yield of taxifolin in 3 validation experiments was 2.79 mg/g. CONCLUSION: Optimizing extraction technics by response surface methodology is reasonable, simple, and has good predictability.

[Study on characteristic HPLC fingerprint of Polygonum orientale inflorescence].

OBJECTIVE: To establish a characteristic HPLC fingerprint of Polygonum orientale inflorescence, and to provide reference for its quality evaluation. METHODS: Taxifolin was used as reference. HPLC analysis was carried out with Diamonsil C18 column (200 mm x 4.6 mm, 5 microm) using acetonitrile -0.1% phosphoric acid(gradient elution)as mobile phase at flow rate of 1.0 mL/min. The detection wavelength was set at 280 nm and the column temperature was 30 degrees C. RESULTS: Eighteen common peaks were pointed out from the HPLC fingerprint of Polygonum orientale inflorescence from 12 different habitats. Among of them,four common peaks were identified as taxifolin, catechin, gallic acid and 3,3'-dimethyl ellagic acid-4-O-beta-D-glucoside. Analyzed by "Similarity Evaluation for Chromatographic Fingerprint of Traditional Chinese Medicine" software, the HPLC fingerprint similarities of 12 samples were more than 0.9. CONCLUSION: This method is repeatable and exclusive. It can be used for identification and quality control of Polygonum orientale inflorescence.

[Determination of taxifolin in Polygonum orientale of different storage period].

OBJECTIVE: To find out the correlation between the content of taxifolin in Polygonum orientale and the storage time. METHOD: HPLC was used to determine taxifolin. The chromatographic condition was as following: Diamonsil C18 column (4.6 mm x 200 mm, 5 microm), mobile phase acetonitrile -0.1% phosphoric acid (gradient elution), the detection wavelength 290 nm and flow rate 1.0 mL x min(-1), the column temperature 30 degrees C. RESULT: The injection volume of taxifolin was in good linearity within 0.07 and 0.35 microg, the average recovery was 99.7% with RSD 0.2%. Taxifolin content was 0.84, 1.36, 1.75, 1.99 mg x g(-1) corresponding to storage time of 10, 7, 6, 5 years, respectively. CONCLUSION: The content of taxifolin decreased with the storage time. When the storage period is more than six years, the content is lower than that required by Chinese Pharmacopoeia (2010 version). This method has a good repeatability and accuracy, it provides a scientific reference for clinical use and quality evaluation of P. orientale.

[Simultaneous determination of four flavones in root and stem of Cudrania tricuspidata and C. cochinchinensis by HPLC-DAD].

OBJECTIVE: To establish a HPLC-DAD method for the determination of axifolin, naringenin, quercetin and kaempferol in Cudrania tricuspidata and C. cochinchinensis in order to provide a scientific reference for species identification and quality evaluation, by establishing. METHOD: The determination was performed by HPLC-DAD on an Agilent C18 column (4.6 mm x 150 mm, 5 microm) by gradient elution (0-15 min, 35%-50% A; 15-30 min, 50% - 65% A) using methanol (A) and 0.1% phosphoric acid (B) as the mobile phase. The flow rate was 1 mL x min(-1). The detection wavelength was 290 nm for taxifolin and naringenin, 365 nm for quercetin and kaempferol with column temperature at 30 degrees C. RESULT: The content of axifolin and quercetin in the root of C. tricuspidata were remarkably higher than that in the root of C. cochinchinensis, and the content in stem of C. tricuspidata was also higher than that in the stem of C. cochinchinensis, the content of axifolin and quercetin was variable in different species. The content of naringenin and kaempferol in the root of C. cochinchinensis was visibly higher than that in the root of C. tricuspidata, and the content in the stems of the two herbs was similar, the content of naringenin and kaempferol was visibly variable in different medicinal parts of the herb, but similar between the two herbs. CONCLUSION: There's some difference of the content of the four ingredients in different medicinal parts and different herbs, so clinical use should not be confused.

Predefined-Time Adaptive Neural Tracking Control of Switched Nonlinear Systems.

This article investigates the neural-network-based adaptive predefined-time tracking control problem for switched nonlinear systems. Neural networks are employed to approximate the unknown part of nonlinear functions. The finite-time differentiators are introduced to estimate the first derivative of the virtual controllers. Then, a novel adaptive predefined-time controller is proposed by utilizing the backstepping control technique and the common Lyapunov function (CLF) method. It is explained by the theoretical analysis that the developed controller guarantees that all signals of the switched closed-loop systems are bounded under arbitrary switchings and the tracking error converges to zero within the predefined time. A simulation is shown to verify the validity of the developed predefined-time control approach.

Construction of carboxymethyl chitosan-based nanoparticles of hypoxia response for co-loading doxorubicin and tanshinone IIA.

As a first-line drug for breast cancer chemotherapy, the effectiveness of doxorubicin (DOX) is challenged by high doses and high toxicity. Studies showed the combination of Tanshinone IIA (TSIIA) and DOX could enhance the efficacy of DOX for cancer and reduce the toxic effects to normal tissues. Unfortunately, free drugs are easily metabolized in the systemic circulation, which are less prone to aggregation at the tumor site to exert anticancer efficacy. In present study, we prepared a carboxymethyl chitosan-based hypoxia-responsive nanoparticles loaded with DOX and TSIIA for the treatment of breast cancer. The results demonstrated that these hypoxia-responsive nanoparticles not only improved the delivery efficiency of the drugs but also enhanced the therapeutic efficacy of DOX. The average size of nanoparticles was about 200-220 nm, the optimal drug loading and encapsulation efficiency of TSIIA in DOX/TSIIA NPs were 9.06 % and 73.59 %, respectively. Hypoxia-responsive behavior were recorded in vitro, while the synergistic efficacy is significantly exhibited in vivo and the tumor inhibitory rate was 85.87 %. Notably, TUNEL assay and immunofluorescence staining verified that the combined nanoparticles exerted a synergistic anti-tumor effect by inhibiting tumor fibrosis, decreasing the expression of HIF-1α and inducing tumor cell apoptosis. Collectively, this carboxymethyl chitosan-based hypoxia-responsive nanoparticles could have promising application prospect for effective breast cancer therapy.

Abnormal regional signal in the left cerebellum as a potential neuroimaging biomarker of sudden sensorineural hearing loss.

Objective: While prior reports have characterized visible changes in neuroimaging findings in individuals suffering from sudden sensorineural hearing loss (SSNHL), the utility of regional homogeneity (ReHo) as a means of diagnosing SSNHL has yet to be established. The present study was thus conducted to assess ReHo abnormalities in SSNHL patients and to establish whether these abnormalities offer value as a diagnostic neuroimaging biomarker of SSNHL through a support vector machine (SVM) analysis approach. Methods: Resting-state functional magnetic resonance imaging (rs-fMRI) analyses of 27 SSNHL patients and 27 normal controls were conducted, with the resultant imaging data then being analyzed based on a combination of ReHo and SVM approaches. Results: Relative to normal control individuals, patients diagnosed with SSNHL exhibited significant reductions in ReHo values in the left cerebellum, bilateral inferior temporal gyrus (ITG), left superior temporal pole (STP), right parahippocampal gyrus (PHG), left posterior cingulum cortex (PCC), and right superior frontal gyrus (SFG). SVM analyses suggested that reduced ReHo values in the left cerebellum were associated with high levels of diagnostic accuracy (96.30%, 52/54), sensitivity (92.59%, 25/27), and specificity (100.00%, 27/27) when distinguishing between SSNHL patients and control individuals. Conclusion: These data suggest that SSNHL patients exhibit abnormal resting-state neurological activity, with changes in the ReHo of the left cerebellum offering value as a diagnostic neuroimaging biomarker associated with this condition.

Heparan sulfate glycosaminoglycan mimetic improves pressure ulcer healing in a rat model of cutaneous ischemia-reperfusion injury.

Pressure ulcers are a major clinical problem, with a large burden on healthcare resources. This study evaluated the effects of the heparan sulfate glycosaminoglycan mimetic, OTR4120, on pressure ulceration and healing. Ischemia-reperfusion (I-R) was evoked to induce pressure ulcers by external clamping and then removal of a pair of magnet disks on rat dorsal skin for a single ischemic period of 16 hours. Immediately after magnet removal, rats received an intramuscular injection of OTR4120 weekly for up to 1 month. During the ischemic period, normal skin perfusion was reduced by at least 60% and at least 20-45% reperfused into the ischemic region after compression release. This model caused sustained skin incomplete necrosis for up to 14 days and led to grade 2-3 ulcers. OTR4120 treatment decreased the area of skin incomplete necrosis and degree of ulceration. OTR4120 treatment also reduced inflammation and increased angiogenesis. In OTR4120-treated ulcers, the contents of vascular endothelial growth factor, platelet-derived growth factor, and transforming growth factor beta-1 were increased. Moreover, OTR4120 treatment promoted early expression of alpha-smooth muscle actin and increased collagen biosynthesis. Long-term restoration of wounded tissue biomechanical strength was significantly enhanced after OTR4120 treatment. Taken together, we conclude that OTR4120 treatment reduces pressure ulcer formation and potentiates the internal healing bioavailability.

Stimulated neovascularization, inflammation resolution and collagen maturation in healing rat cutaneous wounds by a heparan sulfate glycosaminoglycan mimetic, OTR4120.

Heparan sulfate glycosaminoglycans (HS-GAGs) are not only the structural elements of tissue architecture but also regulate the bioavailability and transduction pathways of heparan sulfate-bound polypeptides released by cells or the extracellular matrix. Heparan sulfate-bound polypeptides include inflammatory mediators, chemokines, angiogenic factors, morphogens, and growth-promoting factors that induce cell migration, proliferation, and differentiation in wound healing. OTR4120, a polymer engineered to mimic the properties of HS-GAGs, is used to replace the natural HS-GAGs that are degraded during wound repair, and enhance the tissue regeneration by preserving the cellular microenvironment and the endogenous signals needed for tissue regeneration. We previously demonstrated that OTR4120 treatment had a long-term effect on increasing breaking strength and vasodilation in healing rat full-thickness excisional wounds. The present study investigates the underlying mechanisms of the effects of OTR4120 treatment in improving the quality of cutaneous wound repair. We found that OTR4120 treatment stimulated inflammation resolution and increased neovascularization. OTR4120 treatment also promoted epidermal migration and proliferation during reepithelialization. Moreover, the granulation tissue formation and collagen maturation were improved in OTR4120-treated wounds. Three months after wounding, the effects of OTR4120 treatment on vascularization and inflammation resolution were normalized, except for an improved neodermis. We conclude that OTR4120 is a potential matrix therapeutic agent that ensures the quality of normal cutaneous wound repair and may restore impaired wound healing characterized by deficient angiogenesis and prolonged inflammation.

RGTA OTR 4120, a heparan sulfate proteoglycan mimetic, increases wound breaking strength and vasodilatory capability in healing rat full-thickness excisional wounds.

ReGeneraTing Agents (RGTAs), a family of polymers engineered to protect and stabilize heparin-binding growth factors, have been shown to promote tissue repair and regeneration. In this study, the effects of one of these polymers, RGTA OTR4120, on healing of full-thickness excisional wounds in rats were investigated. Two 1.5 cm diameter circular full-thickness excisional wounds were created on the dorsum of a rat. After creation of the wounds, RGTA OTR4120 was applied. The progress of healing was assessed quantitatively by evaluating the wound closure rate, vasodilatory capability, and wound breaking strength. The results showed a triple increase of the local vascular response to heat provocation in the RGTA OTR4120-treated wounds as compared with vehicle-treated wounds. On days 14 and 79 after surgery, the wounds treated with RGTA OTR4120 gained skin strength 12% and 48% of the unwounded skin, respectively, and displayed a significantly increased gain in skin strength when compared with control animals. These results raise the possibility of efficacy of RGTA OTR4120 in accelerating surgically cutaneous wound healing by enhancing the wound breaking strength and improving the microcirculation.

Hyperbaric oxygen therapy for wound healing in diabetic rats: Varying efficacy after a clinically-based protocol.

Hyperbaric oxygen therapy (HBOT) is a clinical treatment in which a patient breathes pure oxygen for a limited period of time at an increased pressure. Although this therapy has been used for decades to assist wound healing, its efficacy for many conditions is unproven and its mechanism of action is not yet fully clarified. This study investigated the effects of HBOT on wound healing using a diabetes-impaired pressure ulcer rat model. Seven weeks after streptozotocin-induced diabetes in rats (n = 55), a pressure ulcer was created on dorsal skin. Subsequently, animals received HBOT during 6 weeks following a standard clinical protocol (HBOT group with varying endpoints up to 42 days post-wounding) versus controls without HBOT. Capillary venous oxygen saturation (SO2) showed a significant increase in the HBOT group on day 24; however, this increase was significant at this time point only. The quantity of hemoglobin in the micro-blood vessels (rHB) showed a significant decrease in the HBOT group on days 21 and 42, and showed a trend to decrease on day 31. Blood flow in the microcirculation showed a significant increase on days 17, 21 and 31 but a significant decrease on days 24 and 28. Inflammation scoring showed significantly decreased CD68 counts in the HBOT group on day 42, but not in the early stages of wound healing. Animals in the HBOT group showed a trend for an increase in mean wound breaking strength on day 42.

A multiplexed and miniaturized serological tuberculosis assay identifies antigens that discriminate maximally between TB and non-TB sera.

We have developed a multiplexed and miniaturized TB serological assay with the aim of identifying (combinations of) antigens that maximally discriminate between TB and non-TB patients. It features a microarray accommodating 54 TB antigens, less than 1 microl serum consumption and an indirect immunofluorescence detection protocol. With a panel of 20 TB and 80 non-TB sera we ranked combinations of TB antigens with respect to sensitivity and specificity of TB detection by means of logistic step-forward regression analysis. The highest-ranking TB antigen combination had an area-under-the-curve of the receiver-operator-characteristics (ROC) of 0.95. We also identified an antigen that on its own provided good specificity and sensitivity of TB detection (Ara6-BSA; area-under-the-ROC curve: 0.90). These area-under-the-ROC curve values are exceptionally high for a serological TB assay. We conclude that TB antigen microarrays permit rapid identification of TB antigens that, either alone or in combination, discriminate maximally between TB and non-TB patients and that such identification provides an excellent starting point for developing point-of-care diagnostic assays.

Hyperbaric oxygen therapy to treat diabetes impaired wound healing in rats.

Wound healing in diabetes is frequently impaired and its treatment remains a challenge. Hyperbaric oxygen therapy (HBOT) receives a wide attendance and is often used as a last resort treatment option, however, its effectiveness for many conditions is unproven. We tested the effect of HBOT on healing of diabetic ulcers in an animal experimental setting. Experimental diabetes was induced by intraperitoneal injection of streptozotocin. Four weeks after diabetes induction, rats were ulcerated by clamping a pair of magnet disks on the dorsal skin for 16 h. After magnet removal, the animals received HBOT, daily on weekdays, for 4 weeks. To examine the effect of HBOT on diabetes impaired wound healing, the degree of wound tissue perfusion, inflammation, angiogenesis, and tissue breaking strength were evaluated. HBOT effects on the degree of inflammation and number of blood vessels could not be observed. HBOT improved the tissue breaking strength of the wound, however, this did not reach statistical significance. Twenty hours after ending the HBOT, a significantly improved oxygen saturation of the hemoglobin at the venous end of the capillaries and the quantity of hemoglobin in the micro-blood vessels was measured.

Diabetes-impaired wound healing is improved by matrix therapy with heparan sulfate glycosaminoglycan mimetic OTR4120 in rats.

Wound healing in diabetes is frequently impaired, and its treatment remains a challenge. We tested a therapeutic strategy of potentiating intrinsic tissue regeneration by restoring the wound cellular environment using a heparan sulfate glycosaminoglycan mimetic, OTR4120. The effect of OTR4120 on healing of diabetic ulcers was investigated. Experimental diabetes was induced by intraperitoneal injection of streptozotocin. Seven weeks after induction of diabetes, rats were ulcerated by clamping a pair of magnet disks on the dorsal skin for 16 h. After magnet removal, OTR4120 was administered via an intramuscular injection weekly for up to 4 weeks. To examine the effect of OTR4120 treatment on wound heal-ing, the degree of ulceration, inflammation, angiogenesis, and collagen synthesis were evaluated. We found that OTR4120 treatment significantly reduced the degree of ulceration and the time of healing. These effects were associated with reduced neutrophil infiltration and macrophage accumulation and enhanced angiogenesis. OTR4120 treatment also increased the collagen content with an increase of collagen type I biosynthesis and reduction of collagen type III biosynthesis. Moreover, restoration of the ulcer biomechanical strength was significantly enhanced after OTR4120 treatment. This study shows that matrix therapy with OTR4120 improves diabetes-impaired wound healing.