Effect of individualized therapy for AIDS patients with cytomegalovirus retinitis in intravitreal ganciclovir injections

The effect of intravitreal ganciclovir injection combined with intravenous infusion on acquired immune deficiency syndrome (AIDS) patients with cytomegalovirus retinitis (CMVR) was investigated. A total of 32 eyes in 23 AIDS patients diagnosed as CMVR from 2017 to 2018 were included in the retrospective study. All patients underwent induction therapy by using intravenous drip of the anti-cytomegalovirus (CMV) agent ganciclovir (5 mg/kg q12h) combined with intravitreal ganciclovir injection (3 mg/time, 2 times/wk). The visual acuity, fundus photographs, lesion location, and number of intravitreal injections were observed preoperatively and postoperatively. Totally 14 eyes were cured during induction therapy. The number of injections [4.13 (2 to 6)] in CMVR patients with peripherally fundus lesions were significantly lower than those with central lesions [4.89 (2 to 6)]. The individualized therapy of intravitreal ganciclovir injections for AIDS patients with CMVR can effectively reduce the numbers of intravitreal injections.     

Protective activity of a novel resveratrol analogue,HS-1793, against DNA damage in 137Cs-irradiated CHO-K1 cells

Resveratrol has received considerable attention as a polyphenol with anti-oxidant, anti-carcinogenic, and anti-inflammatory effects. Radiation is an important component of therapy for a wide range of malignant conditions. However, it causes damage to normal cells and, hence, can result in adverse side effects. This study was conducted to examine whether HS-1793, a novel resveratrol analogue free from the restriction of metabolic instability and the high dose requirement of resveratrol, induces a protective effect against radiation-induced DNA damage. HS-1793 effectively scavenged free radicals and inhibited radiation-induced plasmid DNA strand breaks in an in vitro assay. HS-1793 significantly decreased reactive oxygen species and cellular DNA damage in 2 Gy-irradiated Chinese hamster ovary (CHO)-K1 cells. In addition, HS-1793 dose-dependently reduced the levels of phosphorylated H2AX in irradiated CHO-K1 cells. These results indicate that HS-1793 has chemical radioprotective activity. Glutathione levels and superoxide dismutase activity in irradiated CHO-K1 cells increased significantly following HS-1793 treatment. The enhanced biological anti-oxidant activity and chemical radioprotective activity of HS-1793 maintained survival of irradiated CHO-K1 cells in a clonogenic assay. Therefore, HS-1793 may be of value as a radioprotector to protect healthy tissue surrounding tumor cells during radiotherapy to obtain better tumor control with a higher dose.     

闭合复位空心螺钉治疗股骨颈骨折后股骨头坏死的影响因素分析

目的回顾性分析闭合复位空心螺钉治疗股骨颈骨折后股骨头坏死的影响因素。 方法对2009年1月至2017年3月293例采用加压空心螺钉治疗股骨颈骨折的患者进行回顾性分析，其中获得随访的患者247例。应用SPSS20.0软件进行统计学分析，并对影响股骨头坏死的各项因素进行Logistic回归分析。 结果247例患者获得平均58个月（24~80个月）随访，32例出现股骨头坏死，发生率12.9%，随访时髋关节Harris评分平均81.4±3.9分（54~98分）。影响股骨颈骨折术后股骨头坏死的因素和顺序依次为复位质量（OR=9.854，P=0.012），空心钉排列方式（OR=7.965，P=0.017），骨折分型（OR=6.453，P=0.021），空心钉取出与否（OR=5.364，P=0.027），术前是否牵引（OR=2.561，P=0.042）。 结论复位质量是影响股骨颈骨折预后最为关键的因素。空心螺钉正三角形排列、空心螺钉取出以及未及时术前牵引均可能加重股骨头坏死。     

PDCA教学模式在完全中间入路腹腔镜右半结肠CME术中的应用价值

目的探讨PDCA教学模式在完全中间入路腹腔镜右半结肠CME术中的应用价值。方法以2017年1月1日—8月1日时间段随机选取23例于我院行完全中间入路腹腔镜右半结肠癌CME术的患者,依据建档顺序作为对照组,以及2018年1月1日—8月1日时间段随机选取23例我科在施行PDCA教学模式后行相同术式,相同入路,依据建档顺序作为研究组。通过比较实施PDCA学习模式前后,两组手术的手术时间、术中出血量、淋巴结清扫情况、术后恢复时间及住院时间等疗效指标。结果应用PDCA教学模式后,淋巴结清扫更彻底、手术时间缩短、术中出血量减少(P<0.05)。而肠功能恢复时间和术后住院时间上差异无统计学意义(P>0.05)。结论应用PDCA教学模式后,在进行完全中间入路腹腔镜下右半结肠CME手术过程中,熟练度及手术质量有提高,效果显著。     

Modeling the pharyngeal anatomical effects on breathing resistance and aerodynamically generated sound

The objective of this study was to systematically assess the effects of pharyngeal anatomical details on breathing resistance and acoustic characteristics by means of computational modeling. A physiologically realistic nose-throat airway was reconstructed from medical images. Individual airway anatomy such as the uvula, pharynx, and larynx was then isolated for examination by gradually simplifying this image-based model geometry. Large eddy simulations with the FW-H acoustics model were used to simulate airflows and acoustic sound generation with constant flow inhalations in rigid-walled airway geometries. Results showed that pharyngeal anatomical details exerted a significant impact on breathing resistance and energy distribution of acoustic sound. The uvula constriction induced considerably increased levels of pressure drop and acoustic power in the pharynx, which could start and worsen snoring symptoms. Each source anatomy was observed to generate a unique spectrum with signature peak frequencies and energy distribution. Moreover, severe pharyngeal airway narrowing led to an upward shift of sound energy in the high-frequency range. Results indicated that computational aeroacoustic modeling appeared to be a practical tool to study breathing-related disorders. Specifically, high-frequency acoustic signals might disclose additional clues to the mechanism of apneic snoring and should be included in future acoustic studies.     

Conserved residues in yeast initiator tRNA calibrate initiation accuracy by regulating preinitiation complex stability at the start codon

Eukaryotic initiator tRNA (tRNA_i) contains several highly conserved unique sequence features, but their importance in accurate start codon selection was unknown. Here we show that conserved bases throughout tRNA_i, from the anticodon stem to acceptor stem, play key roles in ensuring the fidelity of start codon recognition in yeast cells. Substituting the conserved G31:C39 base pair in the anticodon stem with different pairs reduces accuracy (the Sui⁻ [suppressor of initiation codon] phenotype), whereas eliminating base pairing increases accuracy (the Ssu⁻ [suppressor of Sui⁻] phenotype). The latter defect is fully suppressed by a Sui⁻ substitution of T-loop residue A54. These genetic data are paralleled by opposing effects of Sui⁻ and Ssu⁻ substitutions on the stability of methionylated tRNA_i (Met-tRNA_i) binding (in the ternary complex [TC] with eIF2-GTP) to reconstituted preinitiation complexes (PICs). Disrupting the C3:G70 base pair in the acceptor stem produces a Sui⁻ phenotype and also reduces the rate of TC binding to 40S subunits in vitro and in vivo. Both defects are suppressed by an Ssu⁻ substitution in eIF1A that stabilizes the open/P_OUT conformation of the PIC that exists prior to start codon recognition. Our data indicate that these signature sequences of tRNA_i regulate accuracy by distinct mechanisms, promoting the open/P_OUT conformation of the PIC (for C3:G70) or destabilizing the closed/P_IN state (for G31:C39 and A54) that is critical for start codon recognition.