A-to-I RNA Editing in Klebsiella pneumoniae Regulates Quorum Sensing and Affects Cell Growth and Virulence.

Millions of adenosine (A) to inosine (I) RNA editing events are reported and well-studied in eukaryotes; however, many features and functions remain unclear in prokaryotes. By combining PacBio Sequel, Illumina whole-genome sequencing, and RNA Sequencing data of two Klebsiella pneumoniae strains with different virulence, a total of 13 RNA editing events are identified. The RNA editing event of badR is focused, which shows a significant difference in editing levels in the two K. pneumoniae strains and is predicted to be a transcription factor. A hard-coded Cys is mutated on DNA to simulate the effect of complete editing of badR. Transcriptome analysis identifies the cellular quorum sensing (QS) pathway as the most dramatic change, demonstrating the dynamic regulation of RNA editing on badR related to coordinated collective behavior. Indeed, a significant difference in autoinducer 2 activity and cell growth is detected when the cells reach the stationary phase. Additionally, the mutant strain shows significantly lower virulence than the WT strain in the Galleria mellonella infection model. Furthermore, RNA editing regulation of badR is highly conserved across K. pneumoniae strains. Overall, this work provides new insights into posttranscriptional regulation in bacteria.

Selection of Reference Genes for Normalization of Gene Expression in Thermobia domestica (Insecta: Zygentoma: Lepismatidae).

Zygentoma occupies a key evolutionary position for understanding the evolution of insect metamorphosis but has received little attention in terms of genetic analysis. To develop functional genomic studies in this insect, we evaluated five candidate internal reference genes for quantitative RT-PCR (qPCR) studies from Thermobia domestica, a representative species of Zygentoma, including Actin 5C (Actin5C), Elongation factor-1 alpha (EF1A), Ribosome protein S26 (RPS26), Ribosome protein L32 (RPL32), and Superoxide dismutase 2 (SOD2), at different developmental stages, in various body parts, and under dsRNA microinjection and starvation stresses, using four algorithms (delta Ct, geNorm, NormFinder and BestKeeper) and a comparative algorithm (RefFinder). Specific suitable reference genes were recommended across specific experimental conditions, and the combination of RPS26 and RPL32 was appropriate for all tested samples. Employing our selected reference gene combination, we investigated the gene expression pattern of Myoglianin (Myo), a crucial gene-regulating insect metamorphosis, in ametabolous T. domestica, and demonstrated the efficiency of RNA interference (RNAi) in firebrat nymphs. This study provides a basis for reliable quantitative studies of genes and greatly benefits evolutionary and functional genomics studies in Zygentoma.

Clinical and Microbiological Characterization of Invasive Pulmonary Aspergillosis Caused by Aspergillus lentulus in China.

Invasive aspergillosis (IA) due to Aspergillus lentulus is associated with high mortality. In this study, we investigated the clinical and microbiological characteristics of 6 fatal cases of proven or probable IA caused by A. lentulus in China. Underlying immunosuppression, prior antifungal exposure, and intensive care unit (ICU) hospitalization were important risk factors for invasive A. lentulus infection. Phenotypic differences were observed for A. lentulus isolates including slower growth, reduced sporulation, and inability to grow at 48°C, compared with Aspergillus fumigatus complex. ITS sequencing was unable to distinguish A. lentulus from A. fumigatus, but sequencing of the benA, CaM, and rod A loci enabled reliable distinction of these closely related species. Phylogenetic analysis further confirmed that the ITS region had little variation within the Aspergillus section Fumigati while the benA gene offered the highest intraspecific discrimination. Microsatellite typing results revealed that only loci on chromosomes 1, 3, 5, and 6b generated detectable amplicons for identification. All A. lentulus isolates showed in vitro resistance to multiple antifungal drugs including amphotericin B (MIC range 4 to 8 µg/ml), itraconazole (MIC 2 µg/ml), voriconazole (MIC of 4-16 µg/ml), and posaconazole (MIC of 0.5-1 µg/ml). However, MECs for the echinocandin drugs ranged from 0.03-0.25, ≤0.008-0.015, and ≤0.015-0.03 µg/ml for caspofungin, micafungin, and anidulafungin, respectively. A. lentulus is an emerging fungal pathogen in China, causing fatal disease, and clinicians as well as laboratories should be alert to their increasing presence.

Promoting male circumcision in China for preventing HIV infection and improving reproductive health / 中华男科学杂志

The incidence of heterosexually transmitted HIV infection is rapidly increasing in China, which reached 44.7% among the HIV-positive patients in 2007. With a view to the reduction of HIV transmission and improvement of reproductive health in the Chinese population, this paper introduces the latest evidence obtained from the international epidemiological studies and randomized controlled clinical trials on the preventive effect of male circumcision (MC) on HIV transmission, and elucidates the cellular and molecular mechanisms of HIV transmission through the foreskin. Four studies published during 1997-2007 demonstrated that the mean prevalences of redundant prepuce and phimosis in 15,109 Chinese males aged 3-23 years in 4 areas of China were 43.90 and 11.55% , respectively, while the rate of MC was only 2.66%. As MC is a simple, inexpensive and highly effective technique in HIV prevention, we appeal to the policy-makers in China to conduct a practical program for promoting MC and enhancing male productive health in combination with other approaches to the prevention of HIV infection. MC for neonates, children, adolescents and adults should be included in the health insurance program, and free and timely MC should be performed for the male adults with the high risk of HIV infection and the normal ones whose wives are HIV-positive. Further investigations should be carried out on the epidemiology of redundant prepuce and phimosis, the acceptance and socio-cultural context of MC and the development of simpler and safer methods for MC.

Successful treatment of high-flow priapism by selective arteriographic embolization of the pudendal artery / 中华男科学杂志

<p><b>OBJECTIVE</b>To evaluate the diagnosis and treatment of high-flow priapism (HFP).</p><p><b>METHODS</b>Four cases of HFP following blunt trauma to the penis or perinea underwent diagnostic examination by colour-flow Doppler ultrasound and/or superselective pudendal arteriography, which revealed bilateral arteriocorporal fistula in 1 case and monolateral in the other 3. Penile detumescence was obtained in 2 cases by superselective bilateral/monolateral arteriographic embolization of the pudendal artery with absorbable gelatin</p><p><b>RESULTS</b>The former 2 cases effected an immediate recovery of the sponge, while the other 2 cases received conservative treatment. Erectile function, able to perform normal sexual intercourse in approximately 2 months. But in the latter 2, follow-up revealed unsatisfactory potency.</p><p><b>CONCLUSION</b>Superselective arteriographic embolization with absorbable gelatin sponge can provide a safe, selective and effective treatment for HFP patients.</p>