Clinical characteristics of coronavirus disease 2019 in Gansu province, China.

BACKGROUND: The novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has outbreak in the world. Little is known about the clinical characteristics of patients with SARS-CoV-2 infection in the high-altitude region of China. We reported the clinical characteristics of patients with coronavirus disease 2019 (COVID-19) in Gansu province, China. METHODS: In this retrospective study, patients with laboratory-confirmed SARS-CoV-2 infection were consecutively enrolled from January 21, 2020 to February 11, 2020. The information on the epidemiological, clinical characteristics, laboratory tests, radiological features on admission, treatment and outcome were obtained with the final follow-up of March 13, 2020. On the basis of the median length of hospital stay, patients were further analyzed in two groups (long- vs. short-hospital stay). RESULTS: Of the 86 patients of COVID-19 in 11 cities of Gansu Province, the median hospital stay was 14.0 days (interquartile rang, 11.0-19.0 days). In the overall cohort, the median age was 41.0 years (interquartile rang, 31.0-54.3 years), and 48 (55.8%) patients were female. Forty (46.5%) had a history of exposure to epidemic regions, but none exposed to the Huanan seafood market in Wuhan. Common symptoms included fever (41, 47.7%), and cough (37, 43.0%). On admission, 30 (34.9%) and 58 (67.4%) patients had leukopenia and lymphopenia. According to chest CT scans, 53 (66.3%) of 80 patients showed bilateral pneumonia, and 19 (23.8%) of 80 patients showed unilateral pneumonia. Of the 15 asymptomatic cases, 10 (66.6%) cases were found CT findings of pneumonia. Besides, there were 65 (75.6%) patients with mild and moderate type of COVID-19. All 86 patients received antiviral and traditional Chinese medicine therapy, 53 (61.6%) received antibacterial therapy, and 3 (3.5%) patients received invasive ventilator mechanical ventilation. The proportion of patients received antibiotic treatment in long-hospital stay group was significantly higher than that in the short-hospital stay group (P=0.045). As of March 13, 2020, 84 (97.7%) patients were discharged, and two (2.3%) cases died. CONCLUSIONS: In the Gansu province cohort of 86 patients of COVID-19, most patients were with mild or moderate type, and most asymptomatic cases showed CT imaging findings of SARS-CoV-2 related pneumonia.

Enhanced production of coenzyme Q10 by self-regulating the engineered MEP pathway in Rhodobacter sphaeroides.

Fine-tuning the expression level of an engineered pathway is crucial for the metabolic engineering of a host toward a desired phenotype. However, most engineered hosts suffer from nonfunctional protein expression, metabolic imbalance, cellular burden or toxicity from intermediates when an engineered pathway is first introduced, which can decrease production of the desired product. To circumvent these obstacles, we developed a self-regulation system utilizing the trc/tac promoter, LacI(q) protein and ribosomal binding sites (RBS). With the purpose of improving coenzyme Q10 (CoQ10 ) production by increasing the decaprenyl diphosphate supplement, enzymes DXS, DXR, IDI, and IspD were constitutively overexpressed under the control of the trc promoter in Rhodobacter sphaeroides. Then, a self-regulation system combining a set of RBSs for adjusting the expression of the LacI(q) protein was applied to tune the expression of the four genes, resulting in improved CoQ10 production. Finally, another copy of the tac promoter with the UbiG gene (involved in the ubiquinone pathway of CoQ10 biosynthesis) was introduced into the engineered pathway. By optimizing the expression level of both the upstream and downstream pathway, CoQ10 production in the mutants was improved up to 93.34 mg/L (7.16 mg/g DCW), about twofold of the wild-type (48.25 mg/L, 3.24 mg/g DCW).