Physiologically Based Pharmacokinetic Modeling Suggests Limited Drug-Drug Interaction Between Clopidogrel and Dasabuvir

Dasabuvir, a nonnucleoside NS5B polymerase inhibitor, is a sensitive substrate of cytochrome P450 (CYP) 2C8 with a potential for drug-drug interaction (DDI) with clopidogrel. A physiologically based pharmacokinetic (PBPK) model was developed for dasabuvir to evaluate the DDI potential with clopidogrel, the acyl-β-D glucuronide metabolite of which has been reported as a strong mechanism-based inhibitor of CYP2C8 based on an interaction with repaglinide. In addition, the PBPK model for clopidogrel and its metabolite were updated with additional in vitro data. Sensitivity analyses using these PBPK models suggested that CYP2C8 inhibition by clopidogrel acyl-β-D glucuronide may not be as potent as previously suggested. The dasabuvir and updated clopidogrel PBPK models predict a moderate increase of 1.5-1.9-fold for Cmax and 1.9-2.8-fold for AUC of dasabuvir when coadministered with clopidogrel. While the PBPK results suggest there is a potential for DDI between dasabuvir and clopidogrel, the magnitude is not expected to be clinically relevant.

Novel mutations in the SEC24D gene in Chinese families with autosomal recessive osteogenesis imperfecta

We sought to characterize the phenotypes and identify the SEC24D gene mutations associated with Chinese families of osteogenesis imperfecta (OI). Using whole-exome sequencing, we discovered two novel compound SEC24D mutations of OI patients. Our study extended both the phenotypic and the genotype of the OI patients with SEC24D mutations.

INTRODUCTION

To date, only three compound heterozygous mutations in the SEC24D gene have been found to cause recessively inherited forms of OI. We sought to characterize the phenotypes and to identify the SEC24D gene mutations associated with Chinese families with OI.

METHODS

Using whole-exome sequencing in two probands, we identified two novel compound heterozygous mutations in SEC24D. In family 1, the proband was a 23-year-old male; he had recurrent fractures and dentinogenesis imperfecta. His anterior fontanel was not closed, and he showed facial dysmorphism. A computed tomography three-dimensional imaging of the cranium showed skull deformities associated with a broad ossification defect in the frontoapical area, a widened sagittal suture, and Wormian bones. In family 2, the proband was a 7-year-old boy, who also had recurrent fractures and dentinogenesis imperfecta. His anterior fontanel was not closed, and he did not have obvious facial dysmorphism.

RESULTS

We identified one novel compound heterozygous missense substitution in the proband in family 1, including c.2723G>A (p. Cys908Tyr) and c.2842T>C (p. Ser948Pro). In the proband in family 2, we identified another novel compound heterozygous missense substitution, including c.938G>A (p. Arg313His) and c.875C>T (p. Pro292Leu).

CONCLUSIONS

We discovered two novel compound SEC24D mutations of autosomal recessive OI patients. Our study extended both the phenotypic and the genotypic spectrum of the autosomal recessive OI patients with SEC24D mutations.

RNF11 sequestration of the E3 ligase SMURF2 on membranes antagonizes SMAD7 down-regulation of transforming growth factor β signaling

The activity of the E3 ligase, SMURF2, is antagonized by an intramolecular, autoinhibitory interaction between its C2 and Hect domains. Relief of SMURF2 autoinhibition is induced by TGFβ and is mediated by the inhibitory SMAD, SMAD7. In a proteomic screen for endomembrane interactants of the RING-domain E3 ligase, RNF11, we identified SMURF2, among a cohort of Hect E3 ligases previously implicated in TGFβ signaling. Reconstitution of the SMURF2·RNF11 complex in vitro unexpectedly revealed robust SMURF2 E3 ligase activity, with biochemical properties previously restricted to the SMURF2·SMAD7 complex. Using in vitro binding assays, we find that RNF11 can directly compete with SMAD7 for SMURF2 and that binding is mutually exclusive and dependent on a proline-rich domain. Moreover, we found that co-expression of RNF11 and SMURF2 dramatically reduced SMURF2 ubiquitylation in the cell. This effect is strictly dependent on complex formation and sorting determinants that regulate the association of RNF11 with membranes. RNF11 is overexpressed in certain tumors, and, importantly, we found that depletion of this protein down-regulated gene expression of several TGFβ-responsive genes, dampened cell proliferation, and dramatically reduced cell migration in response to TGFβ. Our data suggest for the first time that the choice of binding partners for SMURF2 can sustain or repress TGFβ signaling, and RNF11 may promote TGFβ-induced cell migration.

[Diagnosis of pulmonary hemorrhage of the newborn infants using lung ultrasonography]

Objective: To investigate the accuracy and reliability of lung ultrasound in diagnosis of pulmonary hemorrhage of the newborn infants. Method: From January 2014 to May 2016, 142 neonates from the Army General Hospital of the Chinese PLA were enrolled in the study. They were divided into two groups: a study group of 42 neonates, who were diagnosed with pulmonary hemorrhage according to their medical history, clinical manifestations and chest X-ray findings, and a control group of 100 neonates with no lung disease. All subjects underwent bedside lung ultrasound in a quiet state in a supine, lateral or prone posture, performed by a single experienced physician. The ultrasound findings were compared between the two groups.Fisher's exact test was uesd for comparison between two groups. Result: The lung ultrasound main findings associated with pulmonary hemorrhage included: (1) Shred sign: which was seen in 40 patients(95%). (2) Lung consolidation with air bronchograms: which were seen in 35 patients(83%). (3) Pleural effusion: which was seen in 34 infants(81%), pleurocentesis confirmed that the fluid was really bleeding.(4)Atelectasis: which was seen in 14 cases(33%). (5) Pleural line abnormalities and disappearing A-lines with an incidence of 100%. (6) Alveolar-interstitial syndrome: 5 patients(12%)had the main manifestations of alveolar-interstitial syndrome. The above signs were not seen in normal controls (all P<0.01) and the normal lung mainly manifested with clear pleural line and A-lines under ultrasound. Conclusion: Lung ultrasonography is accurate and reliable for diagnosing pulmonary hemorrhage, which is suitable for routine application for the diagnosis of pulmonary hemorrhage in the neonatal intensive care unit.

[Association of single nucleotide polymorphism rs6983267 with ulcerative colitis and colorectal cancer]

OBJECTIVE

To investigate the association of rs6983267 polymorphism with risk of sporadic colorectal cancer; to compare the distribution of rs6983267 polymorphism between ulcerative colitis and general population.

METHODS

186 patients with sporadic colorectal cancer, 129 patients with ulcerative colitis and 189 healthy donors were recruited in the case-control study. Peripheral venous blood was obtained, and genomic DNA was extracted. All samples were genotyped using matrix-assisted laser desorption ionization time-of-flight mass spectrometry techniques. Allelic and genotypic frequencies were compared and adjusted for age and gender using unconditional Logistic regression.

RESULTS

The allelic frequency of G and the genotypic frequencies of GG and GT were predominant in colorectal cancer group compared with control group, which were statistically significant after adjustment for age and gender (P<0.001). The allelic frequency of G and the genotypic frequencies of GG and GT were predominant in ulcerative colitis group compared with control group, which were statistically significant as well (P=0.041, P=0.006 and P<0.001).

CONCLUSION

rs6983267 polymorphism was associated with risk of sporadic colorectal cancer. The distribution of rs6983267 may be different between ulcerative colitis and general population, and the frequency of risk allele G may be higher in ulcerative colitis patients compared with general population.

[Normal values of otolith function tests and age-related changes]

Objective:To explore the normal values of otolith function tests and agerelated changes in health volunteers.Method: One hundred and seventyone health volunteers were distributed to seven age groups, all subjects accepted otolith function tests, including fundus photography, static subjective visual vertical(SSVV), cervical vestibular evoked myogenic potential(cVEMP)and ocular vestibular evoked myogenic potential(oVEMP), the fundus photographs was used to measure the discfovea angle(DFA). DFA, SSVV and VEMPs were analyzed and compared among groups. Result: For DFA and SSVV,there were no significant differences either between different ages or between the two eyes in one individual（P>0.05）. For cVEMP, the detection rate declined with age over 60 years old（P<0.01）; the cVEMP threshold increased with every 20 years old(P<0.05); and the cVEMP amplitude decreased with every 10 years old(P<0.05),however, there was an exception that no significant difference was found between 41-50 years old and 51-60 years old groups（P=0.93）;the cVEMP P1 latency prolonged with age over 70 years old（P<0.01）.For oVEMP, the detection rate also declined with age over 60 years old（P<0.01）; the oVEMP threshold was lowest at the age less than 30 years old and the largest threshold was found at the age over 70 years old（P<0.01）; consistently, the oVEMP amplitude was found largest at the age less than 20 years old and lowest at the age over 60 years old(P<0.05).The P1 and N1 latencies were found significantly longer in the group of over 70 years old than other groups（P<0.01）.No significant difference was found between both sides in one individual for oVEMP threshold,amplitude or latency (P>0.05). Conclusion: In health volunteers,there were no obvious aged related changes in DFA and SSVV. However,the detection rate, threshold, amplitude and latency of cVEMP and oVEMP greatly changed with age.

No causal effect of serum urate on bone-related outcomes among a population of postmenopausal women and elderly men of Chinese Han ethnicity--a Mendelian randomization study

SUMMARY

We conducted a Mendelian randomization analysis to assess the effect of serum uric acid on bone-related outcomes using a weighted urate transporter genetic risk score as the instrumental variable. The results showed no significance. Our study identified no evidence of a causal role between uric acid and bone-related outcomes.

INTRODUCTION

Observational studies have associated elevated levels of serum uric acid (SUA) with increasing bone mineral density (BMD) and a lowered prevalence of osteoporotic fractures (OFs) in postmenopausal women and elderly men. However, due to unmeasured confounding variables, these observational studies have not provided insight into the causal relationship between SUA and bone-related outcomes. Our aim was to evaluate the effect of SUA on bone-related outcomes using Mendelian randomization.

METHODS

We recruited 1322 Chinese Han individuals (214 elderly men and 1108 postmenopausal women) from the Shanghai area in China. Mendelian randomization using a two-stage least-squares regression method was conducted with SUA as the exposure variable, a weighted urate transporter genetic risk score as the instrumental variable, and all-site BMD, bone turnover markers, and levels of 25-hydroxyvitamin D3 [25(OH)D], serum calcium (Ca), serum phosphorus (P), and parathyroid hormone (PTH) as outcome variables.

RESULTS

Strong associations between SUA and bone-related outcomes were observed in an ordinary observational analysis (lumbar spine: beta = 0.122, p < 0.0001; hip: beta = 0.104, p < 0.0001; femoral neck: beta = 0.108, p < 0.0001). However, the Mendelian randomization analysis showed no evidence for a causal association of SUA with BMD (lumbar spine: beta = 0.385, p = 0.257; hip: beta = 0.191, p = 0.499; femoral neck: beta = 0.194, p = 0.533). Similar results were found between SUA and other bone-related phenotypes.

CONCLUSIONS

Our study identified no evidence of a causal role between SUA and bone-related outcomes, although strong associations in an observational analysis were observed in a population of postmenopausal women and elderly men.

Molecular Chimeric Recipient Precursor T Cells Promote Cardiac Allograft Survival in Mice

BACKGROUND

Molecular chimerism has become a potential method to induce donor-specific transplant tolerance. We researched the prolongation of cardiac allograft survival by recipient mouse molecular chimeric precursor T cells (pre-T cells) or hematopoietic stem cells (HSCs) infusion in vivo.

METHODS

The donor C57BL/6 mouse MHC-I gene (H-2K(b) and H-2D(b) gene) were amplified by RT-PCR. The identified recipient BALB/c mouse pre-T cells and HSCs were transduced by the pMSCVneo retroviral vector of C57BL/6 mouse MHC-I gene (pMSCVneo-H-2D(b)/H-2K(b)). Then the molecular chimeric cells were transfused back to the BALB/c mice. Allogeneic T-lymphocyte proliferation was assessed in mixed lymphocyte reactions (MLR). A mouse model of heterotopic abdominal heart transplantation was performed to evaluate survival times and histological grade of acute rejection at 7 days after transplantation.

RESULTS

BALB/c mice molecular chimeric pre-T cells and HSCs were cultured successfully after pMSCV-H-2D(b)/H-2K(b) transduction. After the molecular chimeric pre-T cell treatment, the result of MLR showed that the stimulating index of allogeneic T lymphocyte had a statistically significant decrease, which also exhibited a significant reduction after molecular chimeric HSC treatment. The survival time of cardiac allograft was prolonged after chimeric pre-T cell or HSC infusion; meanwhile, pathologic rejection grade decreased significantly. Nevertheless, molecular chimeric pre-T cells exhibited a longer median survival time.

CONCLUSION

The molecular chimeric recipient mouse pre-T cell or HSC infusion reduced spleen T cells' response to allogeneic T cells in vitro and delayed cardiac allograft rejection in vivo. Pre-T cells have more advantages than HSCs on the prolongation of mouse cardiac allograft survival.

Extralevator abdominoperineal excision for low rectal cancer: a systematic review and meta-analysis of the short-term outcome

AIM

The superiority of extralevator abdominoperineal excision (ELAPE) over conventional abdominoperineal excision (APE) remains controversial, despite the publication of many studies on this issue. The aim of this meta-analysis was to provide a clear, evidence-based comparison of the two procedures.

METHOD

A systematic review and meta-analysis was conducted through a comprehensive search of the PubMed, EMBASE/Medline and Cochrane Central Library databases for all studies comparing ELAPE with conventional APE for low rectal cancer. Pooled data on circumferential resection margin (CRM) positivity, intra-operative bowel perforation, perineal wound complications and local recurrence were analysed.

RESULTS

Seven studies, involving a total of 2672 patients, were included. Analysis of the pooled data did not reveal a significant difference between the two operations regarding CRM positivity [risk ratio (RR) = 0.79, 95% CI: 0.40-1.57; P = 0.50, I(2)  = 86%] and perineal wound complications (RR = 0.91, 95% CI: 0.71-1.16; P = 0.44, I(2)  = 49%), and showed a borderline reduced risk of intra-operative bowel perforation for ELAPE, but still did not reveal a significant difference between the two groups (RR = 0.61, 95% CI: 0.37-1.00; P = 0.05, I(2)  = 58%).

CONCLUSION

The current evidence does not indicate a statistically significant superiority of ELAPE over conventional APE in terms of CRM positivity and intra-operative bowel perforation.

Imputation of missing genotypes from low- to high-density SNP panel in different population designs

Imputation of missing genotypes, in particular from low density to high density, is an important issue in genomic selection and genome-wide association studies. Given the marker densities, the most important factors affecting imputation accuracy are the size of the reference population and the relationship between individuals in the reference (genotyped with high-density panel) and study (genotyped with low-density panel) populations. In this study, we investigated the imputation accuracies when the reference population (genotyped with Illumina BovineSNP50 SNP panel) contained sires, halfsibs, or both sires and halfsibs of the individuals in the study population (genotyped with Illumina BovineLD SNP panel) using three imputation programs (fimpute v2.2, findhap v2, and beagle v3.3.2). Two criteria, correlation between true and imputed genotypes and missing rate after imputation, were used to evaluate the performance of the three programs in different scenarios. Our results showed that fimpute performed the best in all cases, with correlations from 0.921 to 0.978 when imputing from sires to their daughters or between halfsibs. In general, the accuracies of imputing between halfsibs or from sires to their daughters were higher than were those imputing between non-halfsibs or from sires to non-daughters. Including both sires and halfsibs in the reference population did not improve the imputation performance in comparison with when only including halfsibs in the reference population for all the three programs.

Correlation of contrast-enhanced ultrasound with two distinct types of blood vessels for the assessment of angiogenesis in lewis lung carcinoma

OBJECTIVE

The aim of our study was to evaluate tumor angiogenesis in Lewis lung carcinoma (LLC) of mice using a contrast-enhanced ultrasound (CEUS) examination, and to determine the correlation of contrast-enhanced ultrasonographic parameters with different blood vessel markers of microvessel density (MVD).

MATERIALS AND METHODS

Subcutaneous Lewis lung carcinomas were established in 25 mice, which were evaluated by contrast-enhanced US using SonoVue (a second-generation US contrast agent). The results were recorded as digital video images and the time-intensity curves and hemodynamic parameters were analyzed. Pathological tumor specimens were obtained just after US examination. Tumor specimens were stained with hematoxylin and eosin (H & E) and expression of CD31 and CD34, the different endothelial cell markers, was determined by immunohistochemical straining. Then the relationship between the CEUS parameters and the level of MVD was analyzed.

RESULTS

Two distinct types of microvessels were identified in Lewis lung carcinoma: differentiated (CD34 +) and undifferentiated (CD31 +) vessels. A significant correlation was found between CEUS parameters and undifferentiated MVD (CD31 + vessels) in LLC (P < 0.05). There was a reverse correlation between the different MVDs.

CONCLUSION

The study showed that among the distinct types of vasculature (CD31 + and CD34 +) in Lewis lung carcinoma, the former correlated with the CEUS parameters. Therefore, CEUS using a second-generation US contrast agent may be useful for the evaluation of tumor angiogenesis of LLC of mice.

Kisspeptin-10 enhanced egg production in quails associated with the increase of triglyceride synthesis in liver

Our previous results showed that kisspeptin-10 (Kp-10) injections via intraperitoneal (i.p.) once daily for three weeks notably promoted the egg laying rate in quails. In order to investigate the mechanism behind the effects of Kp-10 on enhancing the egg laying rate in birds, this study focused on the alternations of lipids synthesis in liver after Kp-10 injections. 75 female quails (22 d of age) were allocated to three groups randomly, and subjected to 0 (control, Con), 10 nmol (low dosage, L) and 100 nmol (high dosage, H) Kp-10 injections via i.p. once daily for three weeks, respectively. At d 52, quails were sacrificed and sampled for further analyses. Serum E2 concentration was increased by Kp-10 injections, and reached statistical significance in H group. Serum triglyceride (TG) concentrations were increased by 46.7% in L group and 36.8% in H group, respectively, but did not reach statistical significance, and TG contents in liver were significantly elevated by Kp-10 injections in a dose-dependent manner. Serum total cholesterol (Tch) concentrations significantly decreased in H group, while in H group the hepatic Tch content was markedly increased. The level of non-esterified fatty acid (NEFA), apolipoprotein A1 and B (apoA1 and apoB) were not altered by Kp-10 injections. The genes expression of sterol regulatory element binding protein-1 (SREBP-1), fatty acid synthetase (FAS), apolipoprotein VLDL-II (apoVLDL-II), cholesterol 7α-hydroxylase (CYP7A1) and vitellogenin II (VTG-II) were significantly up-regulated by high but not low dosage of Kp-10 injection compared to the control group. However, the expression of SREBP-2, acetyl-CoA carboxylase (ACCα), malic enzyme (ME), stearoyl-CoA (Δ9) desaturase 1 (SCD1), apolipoprotein A1 (apoA1), fatty acid binding protein 2 (FABP2), 3-hydroxyl-3-methyl glutaryl-coenzyme A reductases (HMGCR), estrogen receptor α, β (ERα and β) mRNA were not affected by Kp-10 treatment. In line with hepatic mRNA abundance, hepatic SREBP1 protein content was significantly higher in H group. Although the mRNA expression was not altered, the content of ERα protein in liver was also significantly increased in H group. However, SREBP-2 protein content in liver was not changed by Kp-10 treatment. In conclusion, exogenous Kp-10 consecutive injections during juvenile stage significantly advanced the tempo of egg laying in quails, which was associated with the significant elevation in hepatic lipids synthesis and transport.

Effects of kisspeptin-10 on lipid metabolism in cultured chicken hepatocytes

Our previous studies showed that kisspeptin-10 (Kp-10) injected in vivo can markedly increase lipid anabolism in liver of quails. In order to investigate the direct effect of Kp-10 on lipid metabolism of hepatocytes in birds, cells were separated from embryos livers and cultured in vitro with 0, 100 and 1,000 nM Kp-10, respectively. The results showed that after 24 h treatment, cells viability was not affected by 100 nM Kp-10, but showed a mild decrease with 1,000 nM Kp-10 compared to the control cells. Based on the results of the cell viability, 100 nM dosage of Kp-10 was selected for the further study and analysis. Compared with control cells, total cholesterol (Tch) contents in 100 nM treated cells were increased by 51.23%, but did not reach statistical significance, while the level of triglyceride (TG), high density of lipoprotein-cholesterol (HDL-C) and low density of lipoprotein-cholesterol (LDL-C) were significantly increased. Real-time PCR results showed that ApoVLDL-II mRNA expression had a tendency to increase, genes including sterol regulatory element-binding protein-1 (SREBP-1), acetyl coenzyme A carboxylase α (ACCα), carnitine palmitoyltransferase 1 (CPT1), 3-hydroxyl-3-methylglutaryl-coenzyme A reductases (HMGCR) and stearyl coenzyme A dehydrogenase-1 (SCD1) mRNA in hepatocytes were significantly down-regulated by 100 nM Kp-10. However, contrary to its gene expression, SREBP-1 protein expression was significantly up-regulated by 100 nM Kp-10. Some of the significant correlations in mRNA expression were found between genes encoding hepatic factors or enzymes involved in lipid metabolism in liver of birds. These results indicate that Kp-10 stimulates lipid synthesis directly in primary cultured hepatocytes of chickens.

Agents for refractory/relapsed acute lymphocytic leukemia in adults

Although treatment results for adult acute lymphoblastic leukemia (ALL) have improved considerably in the past decades, treating adult patients with relapsed/refractory acute lymphocytic leukemia (ALL) is still difficult. Adults with refractory/relapsed acute lymphocytic leukemia (ALL) processed to death rapidly associated with chemotherapy resistance, high mortality by reinduction, etc. Only 20% to 30% of those patients acquired complete remission (CR). Those patients are always of short duration unless an allogeneic stem cell transplant is feasible. Median survival is only ranging from 2 to 12 months. Therapeutic strategy on relapsed/refractory acute lymphocytic leukemia (ALL) is always a major therapeutic challenge bothering hematological researchers. Novel agents and unique therapeutic strategies have been developed in recent years. This review focuses on major clinical advances in the agents for refractory/relapsed ALL.

High mobility graphene ion-sensitive field-effect transistors by noncovalent functionalization

Noncovalent functionalization is a well-known nondestructive process for property engineering of carbon nanostructures, including carbon nanotubes and graphene. However, it is not clear to what extend the extraordinary electrical properties of these carbon materials can be preserved during the process. Here, we demonstrated that noncovalent functionalization can indeed delivery graphene field-effect transistors (FET) with fully preserved mobility. In addition, these high-mobility graphene transistors can serve as a promising platform for biochemical sensing applications.

Inflammation enhances Y1 receptor signaling, neuropeptide Y-mediated inhibition of hyperalgesia, and substance P release from primary afferent neurons

Neuropeptide Y (NPY) is present in the superficial laminae of the dorsal horn and inhibits spinal nociceptive processing, but the mechanisms underlying its anti-hyperalgesic actions are unclear. We hypothesized that NPY acts at neuropeptide Y1 receptors in the dorsal horn to decrease nociception by inhibiting substance P (SP) release, and that these effects are enhanced by inflammation. To evaluate SP release, we used microdialysis and neurokinin 1 receptor (NK1R) internalization in rat. NPY decreased capsaicin-evoked SP-like immunoreactivity in the microdialysate of the dorsal horn. NPY also decreased non-noxious stimulus (paw brush)-evoked NK1R internalization (as well as mechanical hyperalgesia and mechanical and cold allodynia) after intraplantar injection of carrageenan. Similarly, in rat spinal cord slices with dorsal root attached, [Leu(31), Pro(34)]-NPY inhibited dorsal root stimulus-evoked NK1R internalization. In rat dorsal root ganglion neurons, Y1 receptors colocalized extensively with calcitonin gene-related peptide (CGRP). In dorsal horn neurons, Y1 receptors were extensively expressed and this may have masked the detection of terminal co-localization with CGRP or SP. To determine whether the pain inhibitory actions of Y1 receptors are enhanced by inflammation, we administered [Leu(31), Pro(34)]-NPY after intraplantar injection of complete Freund's adjuvant (CFA) in rat. We found that [Leu(31), Pro(34)]-NPY reduced paw clamp-induced NK1R internalization in CFA rats but not uninjured controls. To determine the contribution of increased Y1 receptor-G protein coupling, we measured [(35)S]GTPγS binding simulated by [Leu(31), Pro(34)]-NPY in mouse dorsal horn. CFA inflammation increased the affinity of Y1 receptor G-protein coupling. We conclude that Y1 receptors contribute to the anti-hyperalgesic effects of NPY by mediating the inhibition of SP release, and that Y1 receptor signaling in the dorsal horn is enhanced during inflammatory nociception.