Assessment of medical waste generation, associated environmental impact, and management issues after the outbreak of COVID-19: A case study of the Hubei Province in China.

COVID-19 greatly challenges the human health sector, and has resulted in a large amount of medical waste that poses various potential threats to the environment. In this study, we compiled relevant data released by official agencies and the media, and conducted data supplementation based on earlier studies to calculate the net value of medical waste produced in the Hubei Province due to COVID-19 with the help of a neural network model. Next, we reviewed the data related to the environmental impact of medical waste per unit and designed four scenarios to estimate the environmental impact of new medical waste generated during the pandemic. The results showed that a medical waste generation rate of 0.5 kg/bed/day due to COVID-19 resulted in a net increase of medical waste volume by about 3366.99 tons in the Hubei Province. In the four scenario assumptions, i.e., if the medical waste resulting from COVID-19 is completely incinerated, it will have a large impact on the air quality. If it is disposed by distillation sterilization, it will produce a large amount of wastewater and waste residue. Based on the results of the study, we propose three policy recommendations: strict control of medical wastewater discharge, reduction and transformation of the emitted acidic gases, and attention to the emission of metallic nickel in exhaust gas and chloride in soil. These policy recommendations provide a scientific basis for controlling medical waste pollution.

Endoscopic characteristics of multidrug-resistant tuberculosis combined with tracheobronchial tuberculosis / 中国内镜杂志

Objective To explore the endoscopic characteristics of multidrug-resistant tuberculosis (MDR-TB) combined with tracheobronchial tuberculosis (TBTB). Methods 248 MDR-TB as study group, they hospitalized from October 1st 2008 to June 31st, 2016. 274 cases of non MDR-TB with bacteria positive as control group over 2015, all of them received bronchoscopy, sputum cultured and drug sensitivity tested of Isoniazid and Rifampicin. We analyzed the results of bronchoscopy and demographic data. Results 248 cases of MDR-TB patients, of 175 (70.56%) were diagnosed TBTB by bronchoscopy, of 73 (29.44%) without TBTB. 274 cases of non MDR-TB with bacteria positive patients, of 146 (53.28%) were diagnosed TBTB, of 128 (46.72%) non TBTB, the difference of comparisons was statistically significant (χ2 = 16.42, P = 0.000). MDR-TB combined with TBTB median age was 32 years, non MDR-TB combined with TBTB median age 42 years, the difference was statistically significant (U = 9932.00, P = 0.001). Among the MDR-TB patients, of 75 (42.86%) TBTB in the upper right bronchial, of71 (40.57%) upper left bronchus, while non MDR-TB patients, of 70 (47.95%) and 60 (41.10%), there was no statistically significant difference (χ2 = 2.44, P = 0.786). Among the MDR-TB, of 76 (43.43%) were inflammation infiltration type, of 11 (6.29%) were necrosis type, of 13 cases (7.43%) granulation proliferative type, of 72 (41.14%) were scar stricture type, of 3 (1.71%) tube wall softening type. Among the non MDR-TB, in turn, TBTB type were 50 (34.25%), 41 (28.08%), 9 (6.16%), 40 (27.40%), 5 (3.43%), the difference were statistically significant (χ2 = 30.50, P = 0.000). Conclusions The detection rate of TBTB was higher in MDR-TB patients, that common occur in younger patients. TBTB common infringe on upper right bronchial and upper left bronchus, TBTB type most are inflammatory infiltration type and scar stricture type. More attention should be paid to bronchoscopy among MDR-TB patients.

Glycerate-oxidizing activity of glycolate oxidase from leaves of Spinacia oleracea.

Glycolate oxidase (GO) was purified to homogeneity from leaves of spinach (Spinacia oleracea). Through detecting the consumption of oxygen and the formation of hydrogen peroxide in the assay solution, it was found that GO could also oxidize glycerate, another metabolite in the photorespiratory pathway, and use FMN and FAD, but not riboflavin and lumiflavin, as its cofactors. The optimum reaction pH, Km for glycerate, k(cat) and activation energy of this oxidizing reaction were determined to be 8.0, 7.14 mmol/L, 1.04 s(-1) and 17.29 kJ/mol, respectively. Oxalate and pyruvate at 5.0 mmol/L could inhibit the glycerate-oxidizing activity by 34% and 26%, and oxalate acted as a competitive inhibitor of the glycerate oxidation reaction with a K(i) of 0.75 mmol/L. By the competition plotting with mixed-substrates, it was indicated that glycolate-oxidizing activity and glycerate-oxidizing activity of GO shared the same active site.