RESEARCH ARTICLE Molecular cloning and expression analysis of a matrix Gla protein gene in the spinyhead croaker, Collichthys lucidus

The matrix Gla (gamma-carboxyglutamic acid-rich) protein (MGP), a vitamin K-dependent and Gla-containing protein, is a calcification inhibitor that mainly functions in tissue calcification and mineralization. In this study, we obtained the complete cDNA sequence of MGP from the spinyhead croaker (Collichthys lucidus), which we named Cl-MGP. Cl-MGP was 923 bp long with a 384-bp open reading fragment that encoded 127 amino acids. The predicted MGP protein sequence contained a 19-residue hydrophobic signal peptide, suggesting that it possesses secretory characteristics. The Gla domain and the invariant unit ErraEtCedyspC, which has been identified in all known vitamin K-dependent vertebrate proteins, were highly conserved in Cl-MGP, suggesting that it uses the same mechanism to function as the known proteins. An alignment analysis revealed that Cl-MGP had the highest identity with Larimichthys crocea (93%), which had lost five amino acid residues in the C-terminal. A quantitative real-time polymerase chain reaction revealed that Cl-MGP expression was highest in the gill, followed by the cholecyst and spleen, with almost no expression in the blood, muscle, or testes. The high Cl-MGP expression in the gill is similar to that observed in other fish species, but the relatively high expression found in the cholecyst and spleen is not seen in all species. Future studies should investigate the tissue distributions of both mRNA and proteins in different species, in order to understand the function and evolution of MGP in different species.

Long-term exposure of K562 cells to benzene metabolites inhibited erythroid differentiation and elevated methylation in erythroid specific genes

Benzene is a common occupational hazard and a widespread environmental pollutant. Previous studies have revealed that 72 h exposure to benzene metabolites inhibited hemin-induced erythroid differentiation of K562 cells accompanied with elevated methylation in erythroid specific genes. However, little is known about the effects of long-term and low-dose benzene metabolite exposure. In this study, to elucidate the effects of long-term benzene metabolite exposure on erythroid differentiation, K562 cells were treated with low-concentration phenol, hydroquinone and 1,2,4-benzenetriol for at least 3 weeks. After exposure of K562 cells to benzene metabolites, hemin-induced hemoglobin synthesis declined in a concentration- and time-dependent manner, and the hemin-induced expressions of α-, β- and γ-globin genes and heme synthesis enzyme porphobilinogen deaminase were significantly suppressed. Furthermore, when K562 cells were continuously cultured without benzene metabolites for another 20 days after exposure to benzene metabolites for 4 weeks, the decreased erythroid differentiation capabilities still remained stable in hydroquinone- and 1,2,4-benzenetriol-exposed cells, but showed a slow increase in phenol-exposed K562 cells. In addition, methyltransferase inhibitor 5-aza-2'-deoxycytidine significantly blocked benzene metabolites inhibiting hemoglobin synthesis and expression of erythroid genes. Quantitative MassARRAY methylation analysis also confirmed that the exposure to benzene metabolites increased DNA methylation levels at several CpG sites in several erythroid-specific genes and their far-upstream regulatory elements. These results demonstrated that long-term and low-dose exposure to benzene metabolites inhibited the hemin-induced erythroid differentiation of K562 cells, in which DNA methylation played a role through the suppression of erythroid specific genes.

Etiology and clinical features of 229 cases of bloodstream infection among Chinese HIV/AIDS patients: a retrospective cross-sectional study

Bloodstream infections (BSIs) are prevalent among people living with HIV/AIDS. The etiology varies in different regions and different periods. We aimed to survey the etiological and clinical features of BSIs in HIV patients in mainland China. We assessed all HIV patients with a positive blood culture in a Chinese teaching hospital from September 2009 through December 2014. We excluded those with specimens likely to have been contaminated. We used Pearson's chi-squared test to measure the differences in characteristics among subgroups of different pathogens. Among 2442 Chinese HIV-seropositive inpatients, 229 (9.38 %) experienced BSIs. The most common pathogens detected included Cryptococcus neoformans (22.7 %), Penicillium marneffei (18.8 %), Mycobacterium tuberculosis (15.3 %), and non-tuberculous mycobacterium (14.8 %). 30/229 (13.1 %) HIV patients with BSIs had a poor prognosis. BSIs are prevalent in hospitalized patients with HIV/AIDS in China. Fungi and mycobacteria are the predominant pathogens.

Cloning, characterization, expression, and feeding response of thyrotropin receptor in largemouth bass (Micropterus salmoides)

Thyrotropin receptor (TSHR) is a G-protein-coupled receptor that regulates the synthesis, storage, and secretion of thyroid hormones in the thyroid tissue. The aims of the present study were to characterize the full-length TSHR cDNA in largemouth bass (Micropterus salmoides), and to determine the TSHR gene transcription levels in different tissues. In addition, the response of TSHR transcription levels to daily feeding in thyroid tissue was investigated. The results showed that the full-length cDNA sequence was 2743 bp with an open reading frame of 2340 bp encoding a 779-amino acid peptide. BLAST analysis indicated that the amino acid sequence displayed 58.4-90.2% identity and 5.6-125.8 divergence, compared with other known fish species. The most abundant TSHR transcription levels were found in the spleen, head kidney, and kidney. Feeding did not affect the transcription level of TSHR in thyroid tissue over the course of the day. Thus, the current study suggests that there was no relationship between daily nutritional status and TSHR transcription level in the thyroid tissue of largemouth bass. The spleen, head kidney, and kidney exhibited the most abundant TSHR transcription levels.

Inhibitor Discovery for the Human GLUT1 from Homology Modeling and Virtual Screening

The human Glucose Transporter 1 (hGLUT1 or SLC2A1) is a facilitative membrane transporter found in the liver, intestines, kidney, and brain, where it transports sugars such as d-glucose and d-galactose. Genetic variations in hGLUT1 are associated with a broad range of diseases and metabolic disorders. For example, hGLUT1 is upregulated in various cancer types (e.g., breast carcinoma) to support the increased anaerobic glycolysis and the Warburg effect. Thus, hGLUT1 is an emerging therapeutic target, which also transports commonly used cancer biomarkers (e.g., (18)F-DG). In this study, we use computational prediction followed by experimental testing, to characterize hGLUT1. We construct homology models of hGLUT1 in a partially occluded outward open ("occluded") conformation based on the X-ray structure of the E. coli xylose transporter, XylE. Comparison of the binding site of the occluded models to experimentally determined hGLUT structures revealed a hydrophobic pocket adjacent to the sugar-binding site, which was tested experimentally via site-directed mutagenesis. Virtual screening of various libraries of purchasable compounds against the occluded models, followed by experimental testing with cellular assays revealed seven previously unknown hGLUT1 ligands with IC50 values ranging from 0.45 μM to 59 μM. These ligands represent three unique chemotypes that are chemically different from any other known hGLUT1 ligands. The newly characterized hydrophobic pocket can potentially be utilized by the new ligands for increased affinity. Furthermore, the previously unknown hGLUT1 ligands can serve as chemical tools to further characterize hGLUT1 function or lead molecules for future drug development.

The effect of two different renal denervation strategies on blood pressure in resistant hypertension: Comparison of full-length versus proximal renal artery ablation

BACKGROUND

Renal denervation (RDN) is used to manage blood pressure (BP) in patients with resistant hypertension (rHT), but effectiveness is still a concern, and key arterial portion for successful RDN is not clear.

OBJECTIVE

The aim of this study was to investigate the efficacy and safety of proximal versus full-length renal artery ablation in patients with resistant hypertension (rHT).

METHODS

Forty-seven patients with rHT were randomly assigned to receive full-length ablation (n = 23) or proximal ablation (n = 24) of the renal arteries. All lesions were treated with radiofrequency energy via a saline-irrigated catheter. Office BP was measured during 12 months of follow-up and ambulatory BP at baseline and 6 months (n = 15 in each group).

RESULTS

Compared with full-length ablation, proximal ablation reduced the number of ablation points in both the right (6.1 ± 0.7 vs. 3.3 ± 0.6, P < 0.001) and the left renal arteries (6.2 ± 0.7 vs. 3.3 ± 0.8, P < 0.001), with significantly shorter RF delivery time (P < 0.001), but higher RF power (P = 0.011). Baseline office BPs was 179.4 ± 13.7/102.8 ± 9.4 mm Hg in the full-length group and 181.9 ± 12.8/103.5 ± 8.9 mm Hg in the proximal group (P > 0.5). Similar office BPs was reduced by -39.4 ± 11.5/-20.9 ± 7.1 mm Hg at 6 months and -38.2 ± 10.3/-21.5 ± 5.8 mm Hg at 12 months in the full-length group (P < 0.001), -42.0 ± 11.6/-21.4 ± 7.9 mm Hg at 6 months and -40.9 ± 10.3/-22.1 ± 5.6 mm Hg at 12 months in the proximal group (P < 0.001), and progressive BP reductions were observed over the 6 months (P < 0.001) in both groups. The drop in ambulatory 24-hr SBP and DBP were significantly less than the drop in office BP (P < 0.001). No renovascular or other adverse complications were observed.

CONCLUSIONS

The results indicate that proximal RDN has a similar efficacy and safety profile compared with full-length RDN, and propose the proximal artery as the key portion for RDN. © 2016 Wiley Periodicals, Inc.

Non-motor symptoms and quality of life in tremor dominant vs postural instability gait disorder Parkinson's disease patients

OBJECTIVES

To explore the differences in the features and impact on quality of life (QOL) of non-motor symptoms (NMS) of tremor dominant (TD) and postural instability gait disorder (PIGD) phenotypes early Parkinson's disease (PD), as well as the determinants of poor QOL for TD and PIGD phenotypes.

METHODS

This cross-sectional study recruited 301 patients with early PD and 101 healthy controls. Specific assessments used for NMS included NMS scale (NMSS), the Hamilton Rating Scale for Depression (HRSD-24), the Hamilton Anxiety Scale (HAMA), the Mini-Mental state examination (MMSE), and Addenbrooke's Cognitive Exam-Revised (ACE-R). QOL was evaluated with the PD Quality of Life Questionnaire (PDQ-39).

RESULTS

Tremor dominant phenotype patients were 117 (38.9%), and PIGD were 155 (51.5%). Compared with TD patients, patients with PIGD had higher frequency of NMS (9.0 ± 5.3 vs 6.7 ± 4.6, P < 0.001), NMSS total scores (39.6 ± 34.5 vs 24.4 ± 22.7, P < 0.001) and more poorly for PDQ-39 summary index (19.2 ± 14.0 vs 13.8 ± 11.5, P = 0.001). There was no difference in the impact of NMS measured with NMSS on QOL between PIGD and TD phenotypes. PIGD phenotype had little impact on poor QOL once the effect of depression was taken into account. Depression was a primary negative predictor for QOL in both TD and PIGD patients (Beta: 0.697 and 0.619, respectively, P < 0.001).

CONCLUSIONS

PIGD phenotype had a higher prevalence of NMS and worse QOL than TD phenotype. Depression is related to a dramatic decline in QOL in both TD and PIGD phenotype patients with PD.

Molecular cloning and gene expression analysis of cystatin C-like proteins in spinyhead croaker Collichthys lucidus

Cystatins are natural tight-binding reversible inhibitors of cysteine proteases. In this study, a cDNA library was constructed from Collichthys lucidus using the SMART technique. A complete cDNA sequence with high identity to the conserved sequence of the cystatin C gene was cloned from the library using EST analysis and rapid amplification of cDNA ends (RACE), then subjected to further investigation. The full-length cDNA of cystatin C from C. lucidus (Clcys) was 699 bp long, including a 5'-terminal untranslated region (5'-UTR) of 52 bp, a 3'-UTR of 290 bp, and an open-reading frame of 357 bp. The gene encoded a polypeptide of 118 amino acids, constituting a predicted molecular weight of 12.875 kDa and a theoretical isoelectric point of 8.81. The amino acid sequence of Clcys possessed typical features of type II cystatins and had the highest identity with cystatin C of Pseudosciaena crocea (89%); therefore, it clustered with the cystatin C group in the UPGMA phylogenetic tree. Quantitative real-time reverse transcription analysis revealed that the highest expression was found in the kidney, followed by the liver, heart, and testis, with the lowest expression in muscle. Interestingly, Clcys had relatively low identity with cystatin C genes from other fish and mammals, and its expression pattern did not possess features of a housekeeping gene. Based on these findings, we suspect that the classification of cystatins in fish is somewhat confusing, and the identification of more cystatin gene sequences is needed before a definite conclusion can be drawn.

Effect of daily sildenafil on patients with absent nocturnal erections due to pelvic fracture urethral disruption: a single-centre experience

Erectile dysfunction (ED) is a common sequel of pelvic fracture urethral disruption. Those patients with nocturnal erections may respond favourably to sildenafil; however, little is known about the response to sildenafil in patients with absent nocturnal erections. The aim was to evaluate the response to the treatment of sildenafil 50 mg taken once daily in the patients with absent nocturnal erections. From January 2008 to December 2011, a total of 28 patients with absent nocturnal erections were evaluated. We recorded nocturnal penile tumescence and rigidity with an erectometer. If nocturnal erections were absent for three nights, patients were administrated sildenafil 100 mg at bedtime and tested again at the fourth night. Penile duplex ultrasound with intracavernous injection was performed to define the cause of ED. All patients received a daily dose of sildenafil 50 mg for 12 weeks. Response to sildenafil treatment was defined as sustained erections allowing vaginal penetration and intercourse. Twenty-three (78%) patients completed the daily sildenafil treatment, and follow-up was available. The nocturnal erections at the fourth night in 13 patients (46.4%) were improved. About 61.5% (8/13) reported effective response to daily sildenafil. The improvement of nocturnal erections induced by sildenafil taken at bedtime might predict the response to sildenafil taken daily.

[Relationship between interleukin-8 levels in expressed prostatic secretion and expressions of bFGF and Bcl-2 in benign prostatic hyperplasia]

OBJECTIVES

To investigate the relationship between interleukin-8 levels in expressed prostatic secretion and expressions of basic fibroblast growth factor (bFGF) and Bcl-2 in benign prostatic hyperplasia (BPH).

METHODS

A series of 50 consecutive patients diagnosed with BPH and scheduled for transurethral resection of the prostate (TURP) were included. Patients were divided into two groups, simple BPH and BPH with chronic prostatitis (CP). The grade of inflammatory changes in the prostate was then determined blindly by two experienced pathologists, according to the classification system. Expressed prostatic secretion (EPS) was collected right before TURP for IL-8 detection using ELISA kits. The resected prostatic tissue was harvested for immunohistochemistry to measure the expression of Bcl-2 and bFGF.

RESULTS

A total of 30 (60%) patients were confirmed to have prostatic histologic inflammation. The volume of the prostate in BPH with CP was obviously larger than that in simple BPH (P=0.022). The NIH chronic prostatitis symptom index (NIH-CPSI) and international prostate symptom score (IPSS) of BPH with CP were both higher than those of simple BPH (P<0.05). Significantly increased levels of IL-8 were observed in EPS obtained from BPH patients with CP (mean level, 43.29 ng/L), compared with patients with simple BPH (mean level, 36.90 ng/L) (P=0.003). The expression of Bcl-2 in BPH with CP (mean level, 6.17) increased significantly, compared with those in simple BPH (mean level, 2.45) (P=0.013). The expression of bFGF in BPH with CP (mean level, 7.57) also obviously elevated, compared with those in simple BPH (mean level, 5.05) (P=0.008). Correlation coefficients of IL-8 levels in EPS and expression of Bcl-2 or bFGF indicated that IL-8 had strong correlation with Bcl-2 and bFGF respectively both in simple BPH and BPH with CP (0<R<1, P<0.05).

CONCLUSIONS

IL-8, Bcl-2 and bFGF are significantly up-regulated in BPH with CP patients, compared with simple BPH patients. Inflammation might play an important role in the outcome and development of benign prostatic hyperplasia and makes it more severe.

Characterization, molecular cloning, and expression analysis of Ecsit in the spinyhead croaker, Collichthys lucidus

Evolutionarily conserved signaling intermediate in Toll pathways (Ecsit) is reported to play an essential role in innate immunity, embryogenesis, and assembly or stability of the mitochondrial complex I. In this study, the full-length cDNA of Ecsit was cloned from the spinyhead croaker Collichthys lucidus based on the expressed sequence tags from our cDNA library constructed using the SMART technique. The cDNA was 1669 bp long, including a 5'-terminal untranslated region (UTR) of 121 bp, a 3'-terminal UTR of 183 bp, and an open reading frame of 1365 bp encoding a 454-amino acid polypeptide. The estimated molecular weight of C. lucidus Ecsit (ClEcsit) was 52.50 kDa with an isoelectric point of 6.14, and contained a typical Ecsit domain that is conserved in other Ecsits. Multiple alignment of ClEcsit with other selected Ecsits suggested that some amino acid residues were highly conserved. Phylogenetic analysis indicated that ClEcsit was more similar to its identities in Sciaenidae and grouped with Ecsits from other Perciformes. Quantitative real-time reverse transcription PCR analysis revealed broad expression of ClEcsit and the transcript was strongly expressed in the gill and weakly expressed in other tissues.