Gag-Pol protein is one of the important structural proteins of human immunodeficiency virus(HIV),comprising the basic scaffold proteins and functional enzymes required during the lifecycle of HIV.Currently,the inhibitors targeting different functional domains on Gag-Pol include capsid(CA)inhibitors,protease inhibitors,reverse transcriptase inhibitors,and integrase inhibitors.The CA inhibitors inhibit the maturation of CA or disrupt the assembly of CA,so as to affect the replication of HIV.The primary mechanism of protease inhibitors is to inhibit the protease from cleaving at the cleavage site CA-spacer peptide 1(SP1).The reverse transcriptase inhibitors block the reverse transcription process of HIV by mimicking the reverse transcription substrates.The integrase inhibitors impact the activity of integrase by targeting the zinc-finger structure at the active center of integrase.This article summarizes the inhibitors targeting HIV Gag-Pol protein and their mechanisms,and reviews the approved dosages and usages of approved patent drugs,so as to provide the references for the future clinical combination therapies and the development of new inhibitors targeting HIV Gag-Pol protein.

Objective To establish an evaluation criterion for high-quality nursing services in comprehensive hospitals of Grade Three in Guangdong Province and provide references for promoting the evaluation of high quality nursing services and standardising high quality nursing services.Methods Based on literature review,brainstorming and references of relevant domestic systems,standards and policies,a pool of evaluation index items and a preliminary questionnaire were constructed.Delphi method was used for two rounds of expert consultations on evaluation indicators.Results The positive coefficients of the two rounds of expert consultations were of 80.00%and 91.67%,respectively,with the authority coefficients both at 0.93.The Kendall coordination coefficients for hospital part were 0.128 and 0.116 respectively,for ward part were 0.193 and 0.107 with statistical differences(both P＜0.001).The evaluation criteria for high-quality nursing services in general hospitals above the third level in Guangdong Province involved in nursing services of hospitals and wards.There were 8 primary indicators,22 secondary indicators and 65 tertiary indicators in the nursing services at hospital part,and 9 primary indicators,23 secondary indicators and 50 tertiary indicators in the nursing services at ward part.Conclusions The evaluation criteria for high-quality nursing services in comprehensive hospitals above the third level in Guangdong Province,established in this study,are scientifically valid and reliable.They allow improvement of management system for the high-quality nursing services as well as guide the healthy development of high-quality nursing services.

Objective:To study the duration of invasive mechanical ventilation (MV) and its influencing factors after neonatal abdominal surgery under general anesthesia in neonatal intensive care unit (NICU).Methods:From January 2018 to December 2020, neonates received abdominal surgery under general anesthesia and needed endotracheal intubation and MV after surgery in NICU of our hospital were retrospectively studied. According to MV duration, the neonates were assigned into <72 h group and ≥72 h group. Multivariate logistic regression was used to analyze the risk factors of postoperative MV duration.Results:A total of 113 neonates were enrolled, including 57 male (50.4%) and 56 female (49.6%). The gestational age was (35.7±3.6) weeks, the birth weight was (2 497±933) g, the average operation age was 9.9(3.6, 22.2) d and the average hospital stay was 22.0(12.0,37.0) d. Congenital intestinal obstruction (37/113, 32.7%) was the most common diagnoses on discharge, followed by neonatal necrotizing enterocolitis(28/113,24.8%) and gastrointestinal perforation (18/113,15.0%). The duration of operation was 80.0 (55.8,117.3) min. All neonates needed MV with endotracheal intubation. The duration of postoperative respiratory support was 30.0(7.0,84.5) h. 48 neonates (42.5%) had endotracheal intubation removed within 24 h after surgery. Multivariate logistic regression analysis showed that preoperative respiratory support ( P=0.004), congenital heart disease( P=0.013) and intravenous midazolam ( P=0.032) were independent risk factors for prolonged postoperative MV. Conclusions:The need of preoperative respiratory support, congential heart disease and intravenous midazolam were independent risk factors for the duration of postoperative MV after neonatal abdominal surgery under general anesthesia.

Cardiopulmonary exercise test(CPET) is the most commonly used non-invasive tool in the world to objectively evaluate cardiopulmonary reserve function and exercise tolerance. CPET play an important role in diagnosis, risk stratification, prognosis evaluation and therapeutic planning in heart failure(HF) patients. In recent years, due to the increasing number of advanced HF patients and the paucity of heart donors, left ventricular assist device(LVAD) has represented a valid alternative to heart transplantation(HT) from bridge to transplantation indication to destination therapy. This article summarizes several topical issues regarding the current use of CPET in assessing the prognosis of HF patients, implantation and withdrawal of LVAD, postoperative right ventricular failure, and the effects of exercise rehabilitation in LVAD patients.

Objective:To explore the effects of bladder volumes from CT simulation on bladder volume consistency and set-up errors during radiotherapy for prostate cancer, aiming to provide a reference for clinical practice.Methods:A retrospective analysis was conducted for of 66 prostate cancer patients treated with intensity-modulated radiation therapy in the Sun Yat-sen University Cancer Center from August 2015 to November 2020. They underwent CT scan or radiotherapy after voluntarily holding in urine. Cone beam computed tomography (CBCT) scans were performed for them to measure their set-up errors in left-right (L-R), superior-inferior (S-I), and anterior-posterior (A-P) directions before each treatment. The bladder contours of the patients were delineated on CT simulation images and CBCT images. Accordingly, bladder volumes were calculated. Based on the calculated bladder volumes derived from the CT simulation images, the patients were divided into three groups: 18 cases in the 200-300 ml group, 24 cases in the 300-400 ml group, and 24 cases in the >400 ml group. Finally, this study analyzed the effects of bladder volumes derived from CT simulation on set-up errors and the changes of CBCT-derived bladder volumes relative to planned volumes during radiotherapy.Results:The bladder volumes in the 200-300 ml, 300-400 ml, and >400 ml groups during radiotherapy were reduced by 15%, 26%, and 32%, respectively. The pairwise comparison indicates statistically significant differences in the changes of bladder volumes among the three groups ( Z=3.43, 7.97, 4.83, P<0.05). Regarding the three-dimensional set-up errors, there were statistically significant differences in S-I set-up errors among the three groups ( H=26.72, P<0.05), but there was no statistically significant difference in L-R and A-P set-up errors ( P>0.05) among these groups. The 200-300 ml, 300-400 ml, and >400 ml groups exhibited S-I set-up errors of 0.00 (-0.20, 0.20) cm, 0.00 (-0.20, 0.30) cm, and -0.10 (-0.30, 0.20) cm, respectively. Therefore, the >400 ml group displayed larger the S-I set-up errors than other two groups, with statistically significant differences ( Z=4.17, 4.66, P< 0.05), while there was no statistically significant differences in S-I set-up errors between other two groups ( P> 0.05). Conclusions:Controlling the bladder filling volumes at 200-300 ml in CT simulation is beneficial for maintaining bladder volume consistency and reducing set-up errors of patients during radiotherapy.

Objective:To investigate the effect of hydroxyurea (HU) combined with temozolomide (TMZ) and radiotherapy (RT) on the sensitivity of human glioma U251 cells to chemoradiotherapy (CRT).Methods:Human glioma U251 cell line was cultured in vitro. CCK8 cell assay was used to detect the proliferation activity of U251 cells treated with different concentrations of HU/TMZ under different conditions. Flow cytometry was utilized to detect apoptosis rate and cell cycle distribution of U251 cells. Transwell chamber assay and scratch test were performed to evaluate the changes of cell invasion and migration. The expression levels of apoptosis proteins were determined by Western blot. Colony formation assay was adopted to detect the cell survival fraction . Results:HU concentration at 50μmol/L and below did not affect the proliferation of human glioma U251 cells ( P>0.05). Low-dose HU combined with CRT significantly inhibited cell proliferation ( P<0.05), invasion ( P<0.01) and migration (12h P<0.001, 24h P<0.01), and promoted cell apoptosis ( P<0.01) compared with the use of CRT alone. Application of 50μmol/L HU combined with RT increased the radiosensitivity of cells (SER=1.49), significantly prolonged the cell cycle of S phase and G 2 phase (both P<0.05), considerably up-regulated the expression levels of the apoptosis-associated proteins of Caspase-3 and Bax and significantly down-regulated the expression level of anti-apoptosis protein of Bcl-2(all P<0.001). Conclusions:Compared with CRT, HU combined with CRT can further inhibit the proliferation, invasion and migration of human glioma U251 cells, promote cell apoptosis, increase the radiosensitivity and prolong the cell cycle of S and G 2 phases, thereby enhancing the sensitivity of human glioma U251 cells to CRT.

Objective:To learn the application of nosocomial infection prevention and control measures as stipulated in COVID-19 emergency plans by medical institutions at all levels in the region, for the purpose of strengthening epidemic prevention and control.Methods:During March 12-13, 2020, customized questionnaires were used to learn from 186 hospitals and medical institutions regarding the basics of their nosocomial prevention management departments, emergency plan application and revisions made. Comparison of the ratios or constituent ratios were tested with χ2 test, while the continuous variables analysis between groups was verified with one-way ANOVA. Results:77.53% of the medical institutions had set up independent nosocomial infection management departments, and 87.30% of the institutions were qualified. 80% of the medical institutions had in place emergency plans for respiratory infectious diseases, but 98.05% of them had revised their plans during the pandemic, with an average of 10.85 newly added and revised provisions. Only 30.11% of emergency planed provide for clearly graded early warning.Conclusions:Efforts should be upgraded to develop an emergency prevention and control system for infection prevention and control in epidemics, and improve technical support for infection prevention and control in the system; to strengthen the clearly-graded early warning and graded responses in a scientific manner; and conduct regular drills, revise plan to ensure its applicability.

Objective: To investigate the impact of bladder filling status on the movement of uterine and on the volume of organs at risk(OAR), so as to provide theoretical basis for individualized internal target volume (ITV) and planning target volume (PTV). Methods: Simulation CT images for a total of 27 patients with locally advanced cervical cancer were acquired with empty bladder, 1.0 h after bladder filling, 1.5 h after bladder filling, respectively. The volumes of uterine corpus, cervix, OARs, CTV and PTV 1.0 h after bladder filling were delineated. The impact of bladder filling status on the displacements of cervix and corpus, volumetric changes of rectum, small intestine, and the volumes of small intestine, bladder and rectum within PTV were analyzed. The correlation between bladder filling status and uterine displacement and volume of OAR was also investigated, as well as the volume of cervix and corpus in the PTV with empty bladder and 1.5 h after bladder filling. Results: Bladder filling status is different for individual cases. The maximum movement range of cervix and uterine body with bladder filling state was 0-3.04 cm and 0-4.31 cm respectively. The anterior displacements of corpus (F=7.818, P<0.05), the volumetric changes of blander, as well the volume of bladder and small intestine in the PTV (F=46.197, 44.609, 29.546, P<0.05) were significantly different between different bladder filling status. The bladder filling status was correlated with the displacements of the anterior of corpus, volumetric changes of small intestine, and the volumes of bladder and small intestine within the PTV (r=-0.232, -0.298, 0.915, -0.336, P<0.05). The volumes of cervix and corpus out of the PTV were significantly different between the empty bladder and 1.5 h after bladder filling (t=-1.326, -1.559, P<0.05). Conclusions Bladder filling status was different for individual patients. The displacements of the anterior of the corpus were significantly affected by the bladder filling status. Increasing the anterior margin of PTV was recommended. The consistency of bladder filling status was critical for the precise cervical cancer IMRT.

Objectives To explore the distribution of CTX-M drug resistance genotypes in Escherichia coli isolated from urethra in children and the influence of pH changes on its drug resistance. Methods A total of 113 strains of Escherichia coli isolated from clean midstream urine in children with urinary tract infection were cultured from October 2013 to May 2014. The drug sensitivity of ESBL-producing Escherichia coli was detected and counted. The distribution of CTX-M drug resistance genotypes were analyzed by PCR and gene sequencing. Different pH environment was established in vitro to evaluate the effect of pH on drug resistance of CTX-M resistant Escherichia coli. Results In 113 Escherichia coli strains, there were 68 ESBL-producing strains (60.18％), in which rate of drug resistance to meropenem and imipenem were 1.47％ and 2.94％ respectively. There were 41 strains carried CTX-M drug resistance genotype, which mainly were type CTX-M-14 and type CTX-M-15, 18 strains each. Compared with neutral environment of the pH value at 6 or 6.5, the rate of Escherichia coli resistant to cefuroxime, cefotaxime, ceftazidime and ceftriaxone had no difference (P>0.05), while the resistance to cefepime was significantly increased when pH was 6.0 (P<0.01). With the pH value at 8 or 8.5, the rate of Escherichia coli resistance to ceftazidime and cefepime was significantly decreased, and with the pH value at 8.5 the rate of Escherichia coli resistance to cefotaxime also significantly decreased (P<0.01). Conclusions The rate of ESBL-producing Escherichia coli resistance to carbapenem antibiotic is low. The rate of Escherichia coli carrying CTX-M drug resistance genotype is high with CTX-M-14 and CTX-M-15 being the most prevalent genotypes. Properly alkalization of urine may contribute to the treatment of CTX-M resistant Escherichia coli in children with urinary tract infection.

Objective:To assess the impact of zero makeup policy for drug and medical supplies on hospitals. Methods:Descrip-tive statistics and comparative analysis were used to analyze the related indicators, profit and loss calculation and the cost of patients from April 2014 to March 2017.Results:After the policy was implemented, the number of outpatients and the number of outpatients choosing general doctors decreased. The average length of hospitalization was 8.88 days, and the proportion of drug consumption was 34.10%. The number of outpatients choosing medical experts, the number of inpatients and the proportion of surgical treatment in-creased. Although the policy benefited patients,the average medical expenditure still increased. There was policy loss in the hospital. Conclusion:The reform promotes the implementation of hierarchical medical system, optimizes the hospital income structure and re-duces drug proportion significantly,which achieves the original intentions of the policy to some extent.