Natural polysaccharide-based biodegradable polymeric platforms for transdermal drug delivery system: a critical analysis.

Natural biodegradable polymers generally include polysaccharides (starch, alginate, chitin/chitosan, hyaluronic acid derivatives, etc.) and proteins (collagen, gelatin, fibrin, etc.). In transdermal drug delivery systems (TDDS), these polymers play a vital role in controlling the device's drug release. It is possible that natural polymers can be used for TDDS to attain predetermined drug delivery rates due to their physicochemical properties. These polymers can be employed to market products and scale production because they are readily available and inexpensive. As a result of these polymers, new pharmaceutical delivery systems can be developed that is both regulated and targeted. The focus of this article is the application of a biodegradable polymeric platform based on natural polymers for TDDS. Due to their biocompatibility and biodegradability, natural biodegradable polymers are frequently used in biomedical applications. Additionally, these natural biodegradable polymers are being studied for their characteristics and behaviors.

Development of an in silico prediction model for chemical-induced urinary tract toxicity by using naïve Bayes classifier.

The urinary tract toxicity is one of the major reasons for investigational drugs not coming into the market and even marketed drugs being restricted or withdrawn. The objective of this investigation is to develop an easily interpretable and practically applicable in silico prediction model of chemical-induced urinary tract toxicity by using naïve Bayes classifier. The genetic algorithm was used to select important molecular descriptors related to urinary tract toxicity, and the ECFP-6 fingerprint descriptors were applied to the urinary tract toxic/non-toxic fragments production. The established naïve Bayes classifier (NB-2) produced 87.3% overall accuracy of fivefold cross-validation for the training set and 84.2% for the external test set, which can be employed for the chemical-induced urinary tract toxicity assessment. Furthermore, six important molecular descriptors (e.g., number of N atoms, AlogP, molecular weight, number of H acceptors, number of H donors and molecular fractional polar surface area) and toxic and non-toxic fragments were obtained, which would help medicinal chemists interpret the mechanisms of urinary tract toxicity, and even provide theoretical guidance for hit and lead optimization.

Development and evaluation of in silico prediction model for drug-induced respiratory toxicity by using naïve Bayes classifier method.

Respiratory toxicity is considered as main cause of drug withdrawal, which could seriously injure human health or even lead to death. The objective of this investigation was to develop an in silico prediction model of drug-induced respiratory toxicity by using naïve Bayes classifier. The genetic algorithm was used to select important molecular descriptors related to respiratory toxicity, and the ECFP_6 fingerprint descriptors were applied to the respiratory toxic/non-toxic fragments production. The established prediction model was validated by the internal 5-fold cross validation and external test set. The naïve Bayes classifier generated overall prediction accuracy of 91.8% for the training set and 84.3% for the external test set. Furthermore, six molecular descriptors (e.g., number of O atoms, number of N atoms, molecular weight, Apol, number of H acceptors and molecular polar surface area) considered as important for the drug-induced respiratory toxicity were identified, and some critical fragments related to the respiratory toxicity were achieved. We hope the established naïve Bayes prediction model could be used as a toxicological screening of chemicals for respiratory sensitization potential in drug development, and these obtained important information of respiratory toxic chemical structures could offer theoretical guidance for hit and lead optimization.

Economic cost analysis of malaria case management at the household level during the malaria elimination phase in The People's Republic of China.

BACKGROUND: In China, malaria has been posing a significant economic burden on households. To evaluate malaria economic burden in terms of both direct and indirect costs has its meaning in improving the effectiveness of malaria elimination program in China. METHODS: A number of study sites (eight counties in five provinces) were selected from the malaria endemic area in China, representing the different levels of malaria incidence, risk classification, economic development. A number of households with malaria cases (n = 923) were surveyed during the May to December in 2012 to collect information on malaria economic burden. Descriptive statistics were used to characterize the basic profiles of selected malaria cases in terms of their gender, age group, occupation and malaria type. The malaria economic costs were evaluated by direct and indirect costs. Comparisons were carried out by using the chi-square test (or Z-test) and the Mann-Whitney U test among malaria cases with reference to local/imported malaria patients, hospitalized/out patients, and treatment hospitals. RESULTS: The average cost of malaria per case was 1 691.23 CNY (direct cost was 735.41 CNY and indirect cost was 955.82 CNY), which accounted for 11.1 % of a household's total income. The average costs per case for local and imported malaria were 1 087.58 CNY and 4271.93 CNY, respectively. The average cost of a malaria patient being diagnosed and treated in a hospital at the county level or above (3 975.43 CNY) was 4.23 times higher than that of malaria patient being diagnosed and treated at a village or township hospital (938.80 CNY). CONCLUSION: This study found that malaria has been posing a significant economic burden on households in terms of direct and indirect costs. There is a need to improve the effectiveness of interventions in order to reduce the impact costs of malaria, especially of imported infections, in order to eliminate the disease in China.

Influence of self-reported chronic rhinosinusitis on health-related quality of life: a population-based survey.

Chronic rhinosinusitis (CRS) is a frequently occurring chronic respiratory disease. There is evidence that effective treatment of CRS can improve patients' quality of life, but the data regarding the extent to which CRS impairs patients' quality of life (QoL) is sparse. This study aimed to evaluate the effect of self-reported CRS on health-related QoL and to determine whether the influence was associated with gender, age and socio-economic status. A four-stage random sampling method was used to select the participants from the general population in Guangzhou, China. All participants were interviewed face-to-face at their homes using a standardized questionnaire. The health-related QoL of each participant was assessed using the SF-36 Health Survey. The scores of the SF-36 after adjusting for gender, age, socioeconomic conditions, smoking and some important comorbid conditions were compared between the CRS group and the non-CRS group using analysis of covariance. A multiple linear regression model with interaction terms was established to determine whether CRS affected QoL to the same degree across the different subpopulations. Among a total of 1,411 participants aged at least 15 years, 118 persons (8.4%) had self-reported CRS. Subjects with CRS had an increased prevalence of allergic rhinitis, chronic obstructive pulmonary disease and gout than subjects without CRS. The CRS group had lower scores in all eight domains and the physical and mental component summary than those without CRS (P<0.05), and the greatest differences were in role emotional function (RE), general health (GH) and role physical function (RP). The impairments of the CRS participants in RE and RP were greater among the females than the males. Moreover, physical domains were affected to greater degrees among the elderly and those with high-level education. In conclusion, CRS is a common chronic disorder. Persons with self-reported CRS perceived themselves as having impaired QoL in both the physical and mental domains. These findings shed new light on the health burden of CRS and should be taken into account by clinicians involved in the care of CRS patients.

[Study on the ecological association between natural radioactivity and childhood leukemia in Guangdong province].

OBJECTIVE: This study was undertaken to evaluate the ecological association between terrestrial natural radionuclide, indoor radon concentration, natural radioactivity and leukemia incidence among children under 18 years of age. METHODS: Data were gathered from the disease surveillance program and literature reading while software SPSS 13.0 was used to calculate the Spearman's correlation. RESULTS: The incidence rates of childhood (0-18 year) leukemia showed significant differences in different places with the highest as 3.13/10(5) in Jiangmen area and the lowest as 0.42/10(5) in Maoming area. The incidence in Jiangmen was 7.45 times higher than that in Maoming. There was a rank correlation between the incidence of childhood leukemia and the mean concentrations of natural radio-nuclides in soil (226Ra and 232Th), with a positive correlation observed for overall leukemia (r(s) = 0.70, P = 0.011; r(s) = 0.66, P= 0.02 for 226 Ra and 232Th respectively) and acute lymphoblastic leukemia (ALL) (r(s) = 0.66, P = 0.019; r(s) = 0.64, P = 0.025 for 226 Ra and 232Th respectively). Associations between the incidence of childhood leukemia and the indoor gamma radiation dose rate, the total annual average effective dose equivalent from natural background radiationwere also analyzed (both r(s) = 0.59, P = 0.042). CONCLUSION: The natural radioactivity was likely to be a causative factor for childhood leukemia in Guangdong.

Prevalence of fatty liver disease and its risk factors in the population of South China.

AIM: To investigate the population-based prevalence of fatty liver disease (FLD) and its risk factors in Guangdong Province, China. METHODS: A cross-sectional survey with multiple-stage stratified cluster and random sampling of inhabitants over 7-year-old was performed in 6 urban and rural areas of Guangdong Province, China. Questionnaires, designed by co-working of epidemiologists and hepatologists, included demographic characteristics, current medication use, medical history and health-relevant behaviors, i.e. alcohol consumption, smoking habits, dietary habits and physical activities. Anthropometric measurements, biochemical tests and abdominal ultrasonography were carried out. RESULTS: Among the 3543 subjects, 609 (17.2%) were diagnosed having FLD (18.0% males, 16.7% females, P > 0.05). Among them, the prevalence of confirmed alcoholic liver disease (ALD), suspected ALD and nonalcoholic fatty liver disease (NAFLD) were 0.4%, 1.8%, and 15.0%, respectively. The prevalence rate (23.0%) was significantly higher in urban areas than (12.9%) in rural areas. After adjustment for age, gender and residency, the standardized prevalence of FLD in adults was 14.5%. Among them, confirmed ALD, suspected ALD and NAFLD were 0.5%, 2.3%, and 11.7%, respectively, in adults and 1.3% (all NAFLD) in children at the age of 7-18 years. The overall prevalence of FLD increased with age in both genders to the peak of 27.4% in the group of subjects at the age of 60-70 years. The prevalence rate was significantly higher in men than in women under the age of 50 years (22.4% vs 7.1%, P < 0.001). However, the opposite phenomenon was found over the age of 50 years (20.6% vs 27.6%, P < 0.05). Multivariate and logistic regression analysis indicated that male gender, urban residency, low education, high blood pressure, body mass index, waist circumference, waist to hip ratio, serum triglyceride and glucose levels were the risk factors for FLD. CONCLUSION: FLD, especially NAFLD, is prevalent in South China. There are many risk factors for FLD.