Oligopeptide transporters serve important functions in nutrition and pharmacology. In particular, these transporters help maintain the homeostasis of peptides. The peptide-transporter PEPT2 is a high-affinity and low-capacity type oligopeptide transporter from the proton-coupled oligopeptide transporter family. PEPT2 has recently received attention because of its potential application in targeted drug delivery. PEPT2 is widely distributed in kidney, central nervous system, and lung of organisms. In general, all dipeptides, tripeptides, and peptide-like drugs such as β-lactam antibiotics and angiotensin-converting enzyme inhibitors could be mediated and transported as a substrate of PEPT2. The design of many extant drugs and prodrugs is based on the substrate structure of PEPT2 to accelerate absorption via peptide transporters. Thus, this paper summarizes the substrate features of PEPT2 to promote the rational design of drugs and prodrugs that target peptide transporters.
In this study, we analyzed 7 virulence genes in 55 Legionella species (including 29 L. pneumophila and 26 non-L. pneumophila strains) which isolated from environmental water sources of the public facilities in Macau by using PCR and real-time PCR. In addition, 29 Legionella pneumophila isolates were subjected to genotyping by sequence-based typing scheme and compared with the data reported. The detection rate of flaA, pilE, asd, mip, mompS, proA and neuA genes in the L. pneumophila were 100.0%, respectively. The neuA gene was not detected in the non-L. pneumophila strains, but flaA, pilE, asd, mip, mompS, and proA genes could be amplified with a positive rate of 15.4%, 15.4%, 53.8%, 38.5%, 15.4%, and 38.5%, respectively. The results from real-time PCR were generally consistent with that of PCR. Those L. pneumophila strains were assigned into 10 sequence types (STs) and ST1 (9/29) was the dominant STs. Four new STs were found to be unique in Macau. The analysis of population structure of L. pneumophila strains which isolated from Macau, Guangzhou and Shenzhen indicated that the similar clones were existed and ST1 was the most prevalent STs. However, the distribution of the subtypes isolated from Macau was not the same extensive as those from Guangzhou and Shenzhen. The different detection rates of the 7 virulence genes in different species of Legionella might reflect their own potential for environmental adaptability and pathogenesis. And the data analyzed from STs diversity indicated the Macau L. pneumophila possessed obvious regional specificity and high genetic diversity.
The extra domain of influenza M2 protein (M2e) is almost completely conserved among all influenza A virus subtypes. M2e is a promising candidate target for the development of a broad-spectrum recombinant influenza A vaccine. However, the immunogenicity of M2e needs to be improved. Copy numbers of M2e and its fusion expression with different carrier proteins may affect its immunopotency. In this study, we designed and created different constructs through genetic fusion of M2e (MSLLTEVETPTRSEWECRCSDSSD) (A/California/05/2009 (H1N1)) with the N-terminus (HBcAg1−149aa+Cys) by insertion in the N-terminus Hepatitis B Core (HBc) antigen 1−149aa and Middle 78-81aa of HBcAg1-149aa to construct a recombinant M2e-based vaccine candidate. These chimeric sequences were expressed in Escherichia coli. We constructed fusion proteins containing influenza A H1N1 influenza virus (2009), as well as one, two, and three copies of M2e and hepatitis B core antigen1-149aa amino acid-optimized codon inserted N and its intermediate. The recombinant protein was expressed and purified. Western blot analysis was employed to evaluate the expression of the M2e recombinant protein containing different copy numbers of M2e. Mice were immunized for two times with the purified fusion protein HBc/M2e BALB/c. Serum levels of M2e antibody gradually increased along with increase in immunity. The levels of different fusion protein M2e antibodies increase with increasing M2e copy number. In addition, the protein antibody level in the N terminal fusion protein is higher than that in intermediate fusion.
Endothelial dysfunction is closely associated with hypertension. Protection of vascular endothelial cell is the key to prevention and treatment of hypertension. Uncaria rhynchophylla total alkaloids and Semen Raphani soluble alkaloid, isolated from traditional Chinese medicine Uncaria rbyncbopbylla and Semen Raphani respectively, exhibit properties of anti-hypertension and protection of blood vessels. In the present study, we observed the protective effect of the combined use of Uncaria rhynchophylla total alkaloids and Semen Raphani soluble alkaloid to the vascular endothelial cell in N'-nitro-L-arginine-induced hypertensive rats and investigate the preliminary mechanism. Blood pressure was detected by non-invasive rats tail method to observe the anti-hypertension effect of drugs. Scanning electron microscopy was used to observe the integrity or shedding state of vascular endothelial cell. The amount of circulating endothelial cells and CD54 and CD62P expression on circulating endothelial cells were tested to evaluate the endothelium function. In this study, we found that the Uncaria rhynchophylla total alkaloids and Semen Raphani soluble alkaloidcompatibility can effectively lower the blood pressure, improve the structural integrity of vascular endothelium, and significantly reduce the number of circulating endothelial cells. Furthermore, the mean fluorescence intensity of CD54 and CD62P expressed showed decrease after the intervention of Uncaria rhynchophylla total alkaloids and Semen Raphani soluble alkaloidcompatibility. In conclusion, the combination of effective components of the Uncaria rhynchophylla total alkaloids and Semen Raphani soluble alkaloiddemonstrated good antihypertension effect and vascular endothelium protective effect. The preliminary mechanism of the protective effect may attribute to relieve the overall low-grade inflammation.
Tourette's syndrome (TS) is an inherited chronic neuropsychiatric disorder characterized by involuntary stereotyped motor and phonic behaviors called tics. Its pathogenesis is still unclear and its treatment remains limited. Our previous basic and clinical studies have shown that traditional Chinese medicine (TCM) preparation Ningdong granule (NDG) is effective for the treatment of TS with little side effects. In the current study, two TS rat models (Apomorphine (Apo)- and 3,3'-iminodipropionitrile (IDPN)-induced) were used to explore the dual regulating effects and mechanisms of NDG on extracellular DA concentration. We found that NDG could regulate the extracellular DA concentration dually: it could make a gradual recovery in extracellular DA content from both an up-regulated level in Apo-induced rats and down-regulated level in IDPN-induced rats measured by high-performance liquid chromatography (HPLC). The protein expression of DA transporter (DAT) was measured by Western blot and the result showed that NDG could elevate DAT expression when DA release was up-regulated and could decrease DAT expression when extracellular DA concentration was down-regulated. The main mechanism of the dual regulating effect of NDG on extracellular DA release might be related to DAT protein expression in TS, through which the released DA is re-uptaken into nerve terminals. Taken together, compared with conventional single-target anti-tics drugs such as haloperidol (Hal), NDG with the dual regulating effect would be more significant for TS treatment.
The aim of this study was to explore the value of contrast-enhanced ultrasound (CEUS) in differentiating small renal masses. A total of 102 small renal masses (≤ 3 cm) in 99 patients were examined using conventional ultrasound (CUS) and CEUS, and the findings were reviewed and evaluated in comparison to pathology. Significant differences between renal cell carcinomas (RCCs) and angiomyolipomas (AMLs) were noted in terms of the orientation and echogenicity on CUS (p < 0.05 for both), but the location, shape, margins, homogeneity, and blood flow signals of RCCs on color Doppler flow imaging (CDFI) were similar to those of AMLs (p > 0.05 for all). On CEUS, however, the enhancement intensity, washout in the late phase, and perilesional rim-like enhancement differed significantly for RCCs and AMLs (p = 0.000 for all). Significant differences between CEUS and CUS in terms of sensitivity (88.9% vs. 55.6%), the negative predictive value (68.0% vs. 29.5%), the false negative rate (9.9% vs. 44.5%), and accuracy (88.3% vs. 58.9%) were noted (p < 0.05 for all). CEUS, with its unique features, has value in diagnosing small RCCs and AMLs and outperforms CUS in differentiation of small RCCs and AMLs.
Monitoring and evaluation (M&E) for human immunodeficiency virus (HIV) capacity building has become a significant step for HIV prevention and control. The M&E system strengthening tool published by the United Nations Joint Programme on HIV/AIDS (UNAIDS) was intended to be the most authoritative assessment tool internationally. Facing the fact that the M&E system in China did not function at an optimum level, we considered taking the international standards for reference. By linguistic validating and different stages’ discussions and revisions, we came up with the Chinese version of the capacity diagnosis tool with at least 12 components and tested its validity and reliability. The tool turned out to have a sufficiently linguistic validation and proved to be a scientific and feasible instrument which was suitable for China's national conditions.
Toad skin extract cinobufatini study has been focused on anticancer activity, especially apoptosis-inducing activity by bufosteroids. The present study examined effect of the toad skin extract on cancer cell migration into model stromal tissues. Human breast carcinoma cell line MDA-MB-231 was incubated in the presence or absence of toad skin extract on a surface of reconstituted type I collagen gel as a model stromal tissue allowing the cells to migrate into the gel. Frozen sections were microscopically observed after azan staining. Data showed a decrease of cell number in a microscopic field and shortening of cell migration into the model stromal tissue in a dose dependent manner. This suggests that toad skin extract may possess migration-preventing activity in addition to cell toxicity such as apoptosis-inducing activity. The multifaceted effects including apoptosis-inducing and cancer cell migration-preventing activities would improve usefulness of toad skin extract cinobufatini as an anticancer medicine.
Understanding causes of disability among elderly individuals is an important public health issue, particularly because of the increasing rate of disabled elderly individuals and the social costs in a rapidly aging society. Accordingly, we aimed to describe the diseases that precede disability and investigate the types of diseases that are related to severe disability among Japanese elderly individuals aged over 75 years. Using claim data from the latter-stage elderly healthcare system and long-term care insurance system, we identified 76,265 elderly individuals over 75 years old who did not qualify as disabled on April 1, 2011. Among them, 3,715 elderly individuals who had been newly qualified as disabled between April 1, 2011 and March 31, 2012 were selected. Disease codes from the medical claim data in the 6 months prior to disability were collected. All descriptions were developed separately for six groups divided by gender and disability level (low, middle, and high). The results of the ordinal logistic analysis including sex and age revealed that men tended to have significantly higher levels of disability (β = 0.417, p < 0.001) than women. Cerebrovascular disorder (CVD) was the most common disease in almost all age and disability level groups. In low-level disability groups, cancer in men (12.8%) and arthropathy and fracture in women (11.9% and 13.5%, respectively) were as common as cerebrovascular disorder (12.2% and 9.7%, in men and women, respectively). Stroke was the most common disease for all genders and disability levels. The diseases preceding low-level disability differed by gender. This study demonstrated the need to consider arthropathy and fracture as well as CVD in order to prevent disability.