As a basic amino acid, histidine has a pK_a close to the acidity of the tumor microenvironment, thus the charge and solubility of histidine are able to vary as the pH changes. Under a neutral environment, histidine is not charged and exhibits hydrophobic properties, while it can be protonated and becomes hydrophilic when exposed to mildly acidic pH, such as tumor microenvironment. Therefore, histidine is widely used in the design of drug delivery systems to target the mildly acidic pH of tumor microenvironment. This article reviews the recent progresses of histidine-based tumor-targeting drug delivery systems, and summarizes the principles on promoting internalization and tuning drug release by taking advantage of histidine. Finally, we point out the common issues on histidine application and illustrate its future prospects.

Both sides of the picornavirus genome have 5'-untranslated region (5'UTR) and 3'- untranslated region (3'UTR). This study demontrated that both the 5'-and 3'-UTR can form complex structures, such as stem-loop, clover and pseudoknot structure, These structures play an important role in the regulaton of the replication and translation of the viruses. This article reviewed the progress of research on the structure and function of picornavirus' 3'-UTR over recent years.
3' Untranslated Regions ; Animals ; Humans ; Nucleic Acid Conformation ; Picornaviridae ; chemistry ; genetics ; metabolism ; Picornaviridae Infections ; virology ; RNA, Viral ; chemistry ; genetics ; metabolism

Animals ; Cardiomegaly ; Constriction ; Heart ; Mice

Objective To compare the mutation sites in human immunodefieiency virus type 1 (HIV-1) vpr gene via of HIV-1 infected individuals from different regions in China with the previous studies, and to provide information for the further study on the relationship between HIV-1 vpr gene mutations and clinical conditions of the patients. Methods Reverse transcription-polymerasc chain reaction (RT-PCR) and nested PCR were used to amplify HIV-1 vpr gene of 398 HIV-1 infected individuals. The amino acid sequences were analyzed to determine polymorphisms, deviation rate and common mutation sites of HIV-1 vpr gene. Meanwhile, the viral load, subsets of lymphocytes and clinical course of patients infected with mutated HIV-1 were analyzed. Results One hundred and fifty three positive samples which were obtained from 398 HIV-1 infected individuals were available for further analysis. The amino acids sequence typing of HIV-1 Vpr were showed that CRF01 AE was 51.63%, subtype C 24.84%, subtype B 17.65%, CRF03_ AB 3.92% and CRF08 BC 1.31%. Eighty four point three percent of 77th amino acid of HIV Vpr sequence was glutamic acid which was significantly different from what overseas researches reported that the R77Q mutation was correlated with long-term non-progression (LTNP) of AIDS. The mutations of the, 63th, 70th, 85th, 86th, 89th and 94th amino acids of HIV Vpr were likely related to the clinical remission of HIV-1 infected individuals. Conclusions M group is the main type of HIV Vpr typing in China, and CRF01 AE is predominant. Some amino acid mutation sites of HIV-1 Vpr are possibly correlated with clinical manifestations of HIV-1 infected individuals.

Cell Transformation, Neoplastic ; drug effects ; genetics ; Dimethyl Sulfoxide ; pharmacology ; Electroporation ; methods ; HL-60 Cells ; Humans ; Membrane Proteins ; genetics ; Neoplasm Proteins ; genetics ; RNA Interference ; RNA, Small Interfering ; genetics ; Stromal Interaction Molecule 1 ; Transfection

OBJECTIVETo observe the efficacy and safety of Qizhi Jiangtang Capsule (QJC) in treating stage 3b diabetic kidney disease (DKD) patients with macroalbuminuria.

METHODSPatients who conformed to the diagnostic criteria of stage 3b DKD were randomly assigned to two groups according to random digital table, the experiment group and the control group, 84 in each group. All patients received a two-week elution period, and then were treated with basic Western therapy. Patients in the experiment group took QJC, 5 pills per time, 3 times a day, while those in the control group took Valsartan Capsule 160 mg each time, once daily. The observation period of follow-ups was limited within 6 months, and the time points were set as the baseline, 1st month, 3rd month, and 6th month. Systolic blood pressure (SBP), diastolic blood pressure (DBS), 24 h urine protein quantitative (24 h UPQ), plasma albumin (ALB), and serum creatinine (SCr) were detected and recorded, and estimated glomerular filtration rate (eGFR) was calculated. The occurrence of hypoglycemic reaction, coagulation disorder, gastrointestinal tract reaction, allergy, hyperkalemia, doubling of creatinine, and overall adverse events were observed and recorded at same time.

RESULTSFinally 81 patients in the experiment group and 80 patients in the control group were effectively included. Compared with the baseline level, SBP and DBS obviously decreased in the control group at month 1 of treatment (P < 0.05), and more significantly decreased at month 6 of treatment (P < 0.01). SBP at month 1, 3, and 6 of follow-ups; DBS at month 6 of follow-ups was lower in the control group than in the experiment group (P < 0.05). At month 1, 3, and 6 of follow-ups, 24 h UPQ of the experiment group was significantly lower than the baseline level (P < 0.01). It was also significantly lower than the level of the control group at the same time point (P < 0.05). There was no significant difference in 24 h UPQ at month 1, 3, and 6 of follow-ups between the control group and the baseline level (P > 0.05). ALB of the experiment group showed an increasing trend. It was significantly higher than the baseline level at month 6 (P < 0.05), which was also higher than that of the control group at same period (P < 0.05). There was no significant difference in the ALB level in the control group (P > 0.05). SCr of two groups showed an increasing trend. SCr of the experiment group was significantly higher at month 1, 3, and 6 follow-ups than the baseline level (P < 0.05). But the increment of SCr was higher in the control group than in the experimental group, and obviously higher than the baseline levels (P < 0.05). eGFR of both groups showed a decreasing trend. The decrement was higher in the control group than in the experimental group (P < 0.05). The proportion of progression of renal functions at month 1, 3, and 6 of follow-ups in the experimental group was 0.0% (0 case), 9.55% (8 cases), and 21.4% (18 cases), while they were 8.3% (7 cases), 21.4% (18 cases), and 40.5% (34 cases) in the control group. There was no statistical difference in the proportion of progression of renal functions between the two groups at month 3 and 6 of follow-ups (P < 0.05). There was no statistical difference in the incidence of adverse reactions between two groups (P > 0.05).

CONCLUSIONQJC could effectively reduce urinary protein of patients with stage 3b DKD, and delay the progression of renal functions.

Adult ; Albumins ; analysis ; Albuminuria ; drug therapy ; Blood Pressure ; drug effects ; Creatinine ; blood ; Diabetic Nephropathies ; drug therapy ; Drugs, Chinese Herbal ; therapeutic use ; Female ; Glomerular Filtration Rate ; Humans ; Male ; Middle Aged ; Tetrazoles ; therapeutic use ; Treatment Outcome ; Valine ; analogs & derivatives ; therapeutic use ; Valsartan

Objective To evaluate the clinical application and safety of CT-guided pereutaneous transthoracic biopsy in the diagnosis of mediastinal masses.Methods Thirty three cases were undertaken CT- guided percutaneous transthoraeie biopsy with automatic biopsy gun and then the sampling specimens were undergone histological examination.The accuracy of puncture,diagnostic correctness and complications were analyzed.Results The operations were performed successfully in all 33 cases(100%),the definite pathologic diagnosis were made in 28 out of 33 cases(85%)and no complications occurred.Conclusion As for midiastinal masses,CT-guided percutaneous transthoracic biopsy is a feasible,successful,efficient interventional diagnostic method with high accuracy in localization,puncture,diagnosis and few complications, which should he recommended in clinical use more widely.(J Intervent Radiol,2007,16:852-854)

This study investigated the mental health status of medical students in China, and analyzed the influencing factors in order to provide evidence for mental health education for medical students. A stratified cluster sampling method was used to recruit medical students from Huazhong University of Science and Technology, China. The questionnaire survey on general information and Symptom Checklist 90 (SCL-90) were used for investigation and analysis. The results showed among the 1137 valid questionnaires, 278 (24.45%) participants had SCL-90 score ≥ 160. The top three mental problems of medical students were obsessive-compulsive disorder, interpersonal sensitivity and depression in terms of the factor score ≥ 2.5 and the number of participants who reflected on the diseases. The third-year medical students had the worst mental health status, and fifth-year medical students had the best mental health status. Students from rural area had more psychological problems than those from urban area; furthermore, students with high professional satisfaction, those who were the single child of the family, non-poor students, and those whose parents had high education level had better mental health status. It was concluded that the mental health of medical students is not optimistic in China. Medical students have some mental health problems of different degrees. Factors that influence the mental health of medical students include academic pressure, professional satisfaction level and family environment.

To investigate the protective effects of eplerenone on adriamycin-induced renal injury and the possible mechanisms involved, 36 male Sprague-Dawley rats were randomly divided into control group, adriamycin nephropathy (AN) group and eplerenone-treated group (100 mg·kg(-1)·d(-1) eplerenone). Blood pressure, 24-h urinary protein, serum potassium, sodium and creatinine were measured 28 days after adriamycin injection (a single tail intravenous injection of 6.5 mg/kg adriamycin). The morphological changes of renal tissues were observed by light and electron microscopy. Immunohistochemistry and Western blotting were performed to examine the expression of TGF-β(1) and desmin in renal cortex. The results showed that 28 days after adriamycin injection, there were no significant changes in the level of serum potassium, sodium, creatinine concentrations and blood pressure values in the rats of the three groups. Meanwhile, the 24-h proteinuria excretion in the AN group was significantly higher than that in the control group (P<0.01), but that in the eplerenone-treated group was substantially reduced when compared with that in the AN group (P<0.05). Mild mesangial cell proliferation and matrix expansion, diffuse deformation and confluence of foot processes in podocytes were found in the AN group. By contrast, rats in the eplerenone-treated group exhibited obvious attenuation of these morphological lesions. The protein expression of TGF-β(1) and desmin in the AN group was markedly up-regulated in contrast to that in the control group (P<0.01), whereas that in the eplerenone-treated group was much lower than in the AN group (P<0.05). It was concluded that eplerenone may ameliorate the proteinuria and the development of pathological alteration in adriamycin-induced nephropathy presumably via the inhibition of cytokine release, and restore the morphology of podocytes independent of its blood pressure-lowing effects.

Objective To explore ability of the vpr gene of human immunodeficiency virus type 1 ( HIV-1 vpr) to induce cell G_2 arrest and apoptosis, and the influence when it mutated, the relationship between Vpr-induced G_2 arrest and apoptosis inductions. Methods Fourteen mutant vpr fragments selected from Chinese patients with HIV. Both eukaryotic expression vector pcDNA3.1( + ) and PCR products purified, double-cut by Hind Ⅲ and BamH Ⅰ and the cut products legated and transformed into competent cells JM109. The 14 reconstructed plasmids electronically transfected into Jurkat-cells, and established cells with pcDNA3. 1-vpr , pcDNA3. 1-vpr-Fs and pcDNA3. 1 blank cells, and without pcDNA3. 1 cell. Cells were harvested after 24 h. mRNA expression was detected by RT-PCR, the DNA content and percentage of apoptosis were monitored by flow cytometry. Results Transfected with 14 mutant HIV-1 Vpr protein, cells display different G_2 percentage and apoptosis ratio. HIV-1 vpr induce cell cycle G_2 arrest and apoptosis, wherase Vpr Fs with a C-terminal end truncation, vector pcDNA3.1( + ) and the blank cells can not. The G_2 percentage and apoptosis ratio reduced when transfected with vpr expressing mutating of 70V, 85P, 86G, 94G compared to the wild type. Subtype AE has a weaker potential to induce cell cycle G_2 arrest and apoptosis. Preliminary, we find that the higher G_2 percentage followed the higher ratio of apoptosis. Conclusion HIV-1 vpr can induce cell cycle G_2 arrest and apoptosis, wherase Vpr Fs with a C-terminal end truncation can not. We firstly found that mutated sites of 70V, 85P, 86G, 94G may reduce the ability of Vpr to induce cell cycle G_2 arrest and apoptosis, subtype AE of vpr in Chinese HIV-1 patients has a weaker potential to induce cell cycle G_2 arrest and apoptosis. Analysis of various mutations in the vpr gene revealed that the extent of Vpr-induced G_2 arrest correlated with the levels of apoptosis. And investigate the pathegenesis of HIV vpr. This can also make a good foundation for further study on gene therapy.