OBJECTIVE: Chronic obstructive pulmonary disease (COPD) is a major health concern in northwest China; however, the impact of particulate matter (PM) exposure during sand-dust storms (SDS) remains poorly understood. Therefore, this study aimed to investigate the association between PM exposure on SDS days and COPD hospitalization risk in arid regions. METHODS: Data on daily COPD hospitalizations were collected from 323 hospitals from 2018 to 2022, along with the corresponding air pollutant and meteorological data for each city in Gansu Province. Employing a space-time-stratified case-crossover design and conditional Poisson regression, we analyzed 265,379 COPD hospitalizations. RESULTS: PM exposure during SDS days significantly increased COPD hospitalization risk [relative risk ( RR) for PM _2.5, lag 3:1.028, 95% confidence interval ( CI): 1.021-1.034], particularly among men and the elderly, and during the cold season. The burden of PM exposure on COPD hospitalization was substantially high in Northwest China, especially in the arid and semi-arid regions. CONCLUSION Our findings revealed a positive correlation between PM exposure during SDS episodes and elevated hospitalization rates for COPD in arid and semi-arid zones in China. This highlights the urgency of developing region-specific public health strategies to address adverse respiratory outcomes associated with SDS-related air quality deterioration.
Humans ; China/epidemiology* ; Pulmonary Disease, Chronic Obstructive/chemically induced* ; Particulate Matter/analysis* ; Hospitalization/statistics & numerical data* ; Male ; Female ; Middle Aged ; Aged ; Air Pollutants/analysis* ; Environmental Exposure/adverse effects* ; Spatio-Temporal Analysis ; Adult ; Sand ; Air Pollution

OBJECTIVESTo explore the therapeutic effects of metformin on rat fatty livers induced by high fat feeding.

METHODSA fatty liver model was established by feeding rats with a high caloric laboratory chow for 12 weeks, then the rats were randomly divided into three groups, i.e. model control group, metformin group and dietary treatment group. A normal control group was organized at the same time. The rats of the metformin group were given metformin 156 mg/kg/d while the other groups were given distilled water of the same volume by stomach feeding. The model control group rats were fed with high caloric laboratory chow while other groups were fed a normal diet. After four weeks, all the animals were sacrificed. Liver index (liver/body weight ratio), serum activities of liver-associated enzymes, blood lipids, liver triglycerides, fasting blood glucose, fasting plasma insulin, HOMA insulin resistance index (HOMA-IR), and the liver histology of rats of all groups were assayed.

RESULTSThe body weight, liver index, serum activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), total cholesterol (TC), triglycerides (TG) and liver triglycerides in the model group increased significantly, while HDL-cholesterol concentration decreased significantly. Fasting blood glucose, fasting plasma insulin and HOMA-IR showed an increasing tendency, but there was no significant difference of those indexes among the three groups. The liver histology in the model group showed moderate to severe steatosis, mainly as macro vesicle steatosis, lobular inflammatory, cell infiltration and necrosis. Compared with the model group, the levels of body weight, liver index, serum ALT, ALP, TC, TG and liver triglycerides in the metformin group were significantly lower and were similar to those of the normal group, while their HDL-cholesterol concentration was significantly higher. The liver histology in the metformin group was nearly normal. In the dietary treatment group, hyperlipidemia persisted, although liver index and GGT were lower and the liver histology changes were somewhat milder.

CONCLUSIONIt is suggestive that metformin might be effective in treating rat fatty liver induced by high fat feeding.

Animals ; Dietary Fats ; administration & dosage ; Fatty Liver ; drug therapy ; etiology ; Hypoglycemic Agents ; therapeutic use ; Male ; Metformin ; therapeutic use ; Random Allocation ; Rats ; Rats, Sprague-Dawley