Genetic recombination of Orientia tsutsugamushi strains from scrub typhus patients in Guangxi, Southwest China, and the analysis of clinical features.

Three Orientia tsutsugamushi genotypic groups belonging to two prototypes (Gilliam and Karp) were identified in scrub typhus patients from Guangxi, Southwest China. Fever, headache, pneumonia, fatigue, chill, and anorexia were the most common clinical signs. Frequent recombination was observed for their 47-kDa gene compared to 56-kDa and 16S genes. Furthermore, patients infected with the Gilliam prototype represent a much higher proportion of pneumonia (6/6, 100%) than those infected with the Karp prototype (4/8, 50%) (p-value = 0.040). This discrepancy is consistent with recent animal tests on rhesus and may indicate different virulence and tissue tropism between different O. tsutsugamushi prototypes.

Weighted least-squares phase-unwrapping algorithm based on the orientation coherence for discontinuous optical phase patterns.

Phase unwrapping is one of the key steps of optical interferogram analysis, among which phase discontinuity is still a challenge. In this paper, we propose a new weighted least-squares phase-unwrapping algorithm for discontinuous optical phase patterns. In the proposed algorithm, the orientation coherence is introduced to define the new weighting coefficient, which can accurately show the wrapped phase quality. According to our proposed algorithm, the new weighting coefficient has a good performance on distinguishing the continuous regions and the discontinuous regions in wrapped phase patterns. This advantage of our algorithm can ensure a more reliable unwrapped result for discontinuous optical phase patterns. We test the proposed algorithm on the computer-simulated speckle phase images and two experimentally obtained phase images, respectively, and compare them with the other five widely used methods. The experimental results demonstrate the performance of our new weighted least-squares phase-unwrapping algorithm.

Draft genome sequence of broad-spectrum antibiotic sparsomycin-producing Streptomyces sparsogenes ATCC 25498 from the American Type Culture Collection.

OBJECTIVES: Sparsomycin, which exhibits rare broad-spectrum antibiotic and antitumour activity against bacteria, Archaea, Eucarya and various cancer cell lines, has been widely used as a powerful tool to study protein synthesis. Here we report the draft genome sequence of Streptomyces sparsogenes ATCC 25498 from the American Type Culture Collection (ATCC), which has become an organism of interest owing to its ability to produce sparsomycin. METHODS: The whole-genome sequence of S. sparsogenes ATCC 25498 was determined using a high-throughput Illumina HiSeq 2000 platform and genome assembly was performed using the SOAPdenovo method. RESULTS: Whole-genome sequencing analysis revealed a genome size of 10.0Mb. A total of 41 secondary metabolite biosynthetic gene clusters were identified. The gene cluster for the biosynthesis of sparsomycin was localised on scaffold 9. CONCLUSIONS: The genome sequence of S. sparsogenes ATCC 25498 will not only aid in understanding the regulatory mechanism of sparsomycin biosynthesis but will also reveal the ability of the isolate to produce novel bioactive secondary metabolites.

[An experimental study of expression of angiotension converting enzyme 2 in myocardium and effect of telmisartan treatment in pressure-overloaded rats].

OBJECTIVE: To study the effect of hypertension and telmisartan treatment on the protein and gene expression of cardiac angiotensin-converting enzyme 2 (ACE2) in pressure-overloaded rats. METHODS: Coarctation of suprarenal abdominal aorta was reproduced in 8 week-old male Sprague-Dawley (SD) rats and then randomized into 4 groups, including a sham group (n=15), a suprarenal aortic coarctation group (model group, n=12), a suprarenal aortic coarctation with low-dose Telmisartan treatment group (low-dose group, 2 mgxkg(-1)xd(-1), n=11) and a suprarenal aortic coarctation with high-dose Telmisartan treatment group(high-dose group, 10 mgxkg(-1)xd(-1), n=13). Telmisartan or equivalent amount of normal saline was gavaged 24 hours before the operation and once every day afterwards for 3 weeks. At the end of 3 weeks, the concentrations of angiotensin (AngII) in plasma and myocardium were measured by radioimmunoassay. Changes in both protein quantity and gene expressions of both ACE2 and ACE were determined by Western blotting analysis and reverse transcription-polymerase chain reaction (RT-PCR) technique, respectively. RESULTS: Suprarenal abdominal aortic coarctation induced a significant increase in the plasma and myocardium AngII concentration [plasma: (495.1+/-55.6) ng/L vs. (269.2+/-39.5)ng/L, myocardium: (103.6+/-23.7) ng/g vs. (49.5+/-13.5) ng/g, both P<0.01] and expressions of gene and protein of ACE (P<0.01) and ACE2 (P<0.05). Telmisartan further increased the concentration of AngII in plasma and myocardium in a dose-dependent manner [plasma: (702.2+/-40.6) ng/L vs. (612.6+/-35.5) ng/L, myocardium (211.5+/-21.5) ng/g vs. (189.6+/-43.6) ng/g, both P<0.05], and induced a dose-dependent increase in both protein and gene expression of ACE2 (protein 1.16+/-0.06 vs. 0.79+/-0.04, gene 0.54+/-0.08 vs. 0.41+/-0.04, both P<0.05). Expression of ACE2 protein in low-dose and high-dose groups was increased by 1.0 and 1.58 folds respectively, and gene was increased by 1.3 and 1.6 folds (all P<0.05). The expression of ACE protein and gene in model group increased significantly (protein: 2.10+/-1.07 vs. 1.02+/-0.05, gene: 1.93+/-0.09 vs. 0.26+/-0.09, both P<0.01). Telmisartan had no significant effect on ACE gene and protein expressions (both P>0.05). CONCLUSION: Suprarenal abdominal aortic coarctation induced a significant increases of ACE and ACE2 gene and protein expressions. Telmisartan induces a dose-dependent increases of cardiac ACE2 gene and protein expression,which may be the mechanism of its therapeutic effects.