Dentinal mineralization is not limited in the mineralization front but occurs along with the entire odontoblast process

The mineralization-front theory is historically rooted in mineralization research fields for many decades. This theory is widely used to describe mineralization events in both osteogenesis and dentinogenesis. However, this model does not provide enough evidence to explain how minerals are propagated from the pulp-end dentin to dentin-enamel junction (DEJ). To address this issue, we modified the current research approaches by a) extending the mineral deposition windows of time from minutes to hours, instead of limiting the mineralization assay on days and weeks only; b) switching a regular fluorescent microscope to a more powerful confocal microscope; in which both mineral deposition rates and detail mineral labeling along with dentin tubules can be documented; and c) using reporter mice, including the Gli1-CreERT2 activated tomato and the 2.3 Col1-GFP to mark odontoblast processes combined with mineral dye injections. Our key findings are: 1) Odontoblast-processes, full of numerous mini-branches, evenly spread to entire dentin matrices with a high density of processes and a large diameter of the main process at the predentin-dentin junction; and 2) The minerals deposit along with entire odontoblast-processes and form many individual mineral collars surrounding odontoblast processes. As a result, these merged collars give rise to a single labeled line at the dentin-predentin junction, in which the dental tubules are wider in diameter and denser in odontoblast processes compared to other dentin areas. We therefore propose that it is the odontoblast-process that directly contributes to mineralization, which is not simply limited in the mineralization front at the edge of dentin and predentin, but occurs along with the entire odontoblast process. These new findings will shed new light on our understanding of dentin structure and function, as well as the mechanisms of mineralization.

[Role of Rac1 signaling pathway of azathioprine and peptidoglycan in the regulation of monocyte-macrophage apoptosis in Crohn's disease]

Objective: To evaluate the changes of macrophages and expression of Rac1 in the inflammatory site of Crohn's disease, and to investigate the effects of 6-thioguanine (6-TG) and peptidoglycan on apoptosis of human peripheral blood monocyte-macrophage by regulating Rac1 signaling pathway. Methods: Ten patients with Crohn's disease and eight healthy controls diagnosed were enrolled at Department of Gastroenterology and Hepatology, Tianjin Medical University General Hospital from January 2013 to January 2014. The number of macrophages, apoptosis and expression of Rac1 in the inflammation sites and non-inflammation sites of intestinal mucosa were detected in both patients and controls. Peripheral blood mononuclear cells (PBMCs) were sorted by CD₁₄ immunomagnetic beads. The apoptosis of monocytes, expression of Rac1 and related apoptosis signaling molecules were detected in patients treated with peptidoglycan, 6-TG and Rac1 inhibitor NSC23766 and another 15 healthy donors. Results: The number of macrophages and apoptotic cells significantly increased in the inflammatory group of Crohn's disease patients compared with the non-inflammatory group. The expression of PAK1, downstream molecular of Rac1 signaling pathway of macrophages was also significantly higher in the inflammatory group of Crohn's disease patients than that in healthy controls and non-inflammatory group. Compared with control group, anti-apoptotic signals (NF-κB, Bcl-xL and STAT-3) in PBMCs increased in the peptidoglycan group, while slightly decreased in 6-TG group. 6-TG and NSC23766 significantly promoted peptidoglycan-related anti-apoptosis [peptidoglycan group (8.6±3.7)%, peptidoglycan+ 6-TG group (42.0±2.7)%, peptidoglycan+ NSC23766 group (58.5±6.9)%, P<0.05]. Conclusions: Peptidoglycan plays a role in the pathogenesis of Crohn's disease by recruiting macrophages. However, 6-TG inhibits peptidoglycan-induced activation of Rac1 signaling pathway leading to macrophage apoptosis.

DHX15 promotes prostate cancer progression by stimulating Siah2-mediated ubiquitination of androgen receptor

Androgen receptor (AR) activation is critical for prostate cancer development and progression, including castration-resistance. The nuclear export signal of AR (NES^AR) plays an important role in AR intracellular trafficking and proteasome-dependent degradation. Here, we identified the RNA helicase DHX15 as a novel AR co-activator using a yeast mutagenesis screen and revealed that DHX15 regulates AR activity by modulating E3 ligase Siah2-mediated AR ubiquitination independent of its ATPase activity. DHX15 and Siah2 form a complex with AR, through NES^AR. DHX15 stabilized Siah2 and enhanced its E3 ubiquitin ligase activity, resulting in AR activation. Importantly, DHX15 was upregulated in prostate cancer specimens and its expression was correlated with Gleason scores and PSA recurrence. Furthermore, DHX15 immunostaining correlated with Siah2. Finally, DHX15 knockdown inhibited the growth of C4-2 prostate tumor xenografts in mice. Collectively, our data argue that DHX15 enhances AR transcriptional activity and contributes to prostate cancer progression through Siah2.

Forty-one cases of round ligament varicosities that are easily misdiagnosed as inguinal hernias

PURPOSE

To demonstrate the benefit and safety of conservative therapy for round ligament varicosities (RLVs) that are easily misdiagnosed as inguinal hernias.

METHODS

We retrospectively analyzed clinical materials of 41 consecutive cases of RLVs diagnosed by ultrasound in a single hospital from January 2011 to December 2015. Misdiagnosis rate, clinical and sonographic features, management after diagnosis and prognosis were recorded.

RESULTS

All forty-one cases were pregnant females in their second or third trimester. Twenty-eight cases were first misdiagnosed as inguinal hernias (68.3%). Thirty cases presented as reducible swelling in the inguinal area (73.2%), and twenty-five of which were painful (61.0%). Four cases only felt pain in the inguinal area without swelling (9.7%). Seven cases had no obvious discomfort (17.1%). All cases were diagnosed as RLVs by gray-scale and color Doppler ultrasonography and justified a wait-and-see strategy. Thirty-seven cases were followed until total recovery after delivery (follow-up rate 90.2%). Swelling with or without pain disappeared spontaneously postpartum.

CONCLUSIONS

RLVs are easily misdiagnosed as inguinal hernias and color Doppler of the inguinal area is the best examination for making the correct diagnosis. Conservative therapy for RLV is beneficial and safe when assured by color Doppler.

Impact of FOXP3 Polymorphisms on the Blood Level of Tacrolimus in Renal Transplant Recipients

INTRODUCTION

Tacrolimus is an immunosuppressive medication for organ transplantation. FOXP3(+) T regulatory cells (Tregs) play roles in suppression of rejection and induction of graft tolerance. This study aimed to evaluate the correlation between the polymorphism of FOXP3 and the blood level of tacrolimus in renal transplant recipients.

METHODS

This retrospective study included 100 renal transplant recipients receiving tacrolimus treatment and 100 healthy control subjects. Genotyping for FOXP3 rs3761547 AA, AG, GG, rs3761548 AA, AC, CC and rs223236 AA, AG, GG was performed. Concentrations of tacrolimus, creatinine, and urea nitrogen levels in blood were measured.

RESULTS

Frequencies of genotypes of FOXP3 rs3761548 AA, AC, and CC, rs3761547 AA, AG, GG and rs 223236 AA, AG, GG in renal transplant recipients were similar to those in normal people. The blood level of tacrolimus in recipients with rs3761548 CC was significantly higher than that in recipients with rs3761548 AA and AC (P < .001). No difference in the blood level of tacrolimus was found in recipients with different genotypes of rs3761547 and rs223236. Compared to rs3761548 AA and AC groups, there was no difference of Modification of Diet in Renal Disease (MDRD) glomerular filtration rate and the level of blood urea nitrogen before transplantation; however, these 2 parameters were significantly improved after transplantation in the rs3761548 CC group. The level of tacrolimus was correlated positively with MDRD glomerular filtration rate and negatively with the blood urea nitrogen level in recipients with rs3761548 CC genotype after transplantation.

CONCLUSIONS

Our study identified a new relationship between FOXP3 rs3761548 and the blood level of tacrolimus. These results suggest that the polymorphism of FOXP3 may affect tacrolimus pharmacokinetics.

[Clinical features and prognostic analysis of neuromyelitisoptica spectrum disease with sjogrensyndrome]

Objective: To explore the clinical features and conduct prognostic analysis about visual recovery and relapse of neuromyelitisoptica (NMO) spectrum disease (NMOSD) with sjogren syndrome (SS). Methods: A retrospective and prospective observational study was conducted.Between July 2013 and June 2016, 172 patients with NMOSD (NMOSD-non SS: 116/172, 67.4%; NMOSD-SS: 56/172, 32.6%) were assessed at Beijing Tongren Hospital, Capital Medical University, Beijing, China.The prognostic factors of NMOSD-SS patients were also analyzed. Results: As compared with NMOSD-non SS patients, NMOSD-SS patients had worse visual impairment (percentage of patients with visual acuity less than 0.1, 83.9% vs 69.8%, P<0.05), higher positive rate of SSA (92.9% vs 0.0%, P<0.05), higher proportion of dryness of mouth and eye (66.1% vs 5.2%, P<0.05) as well as higher percentage of reduced visual evoked potential (VEP) amplitude (60.7% vs 43.1%, P<0.05). NMOSD-SS patients had a significantly higher average year recurrent frequency (0.58 vs 0.53) and significantly shorter mean recurrence time (6.7 months vs 12.4 months, P<0.05). The results showed that recurrent eyes, the worst visual acuities of onset less than 0.1 were independent risk factors of visual impairment (visual activity <0.1), according to at least six months' follow-up of all NMOSD-SS patients (OR=6.410 and 9.434, respectively, P<0.05). Meanwhile, immunosuppressive drugs were protective factors of relapse in NMOSD-SS patients (OR=0.107, P<0.05). Conclusions: NMOSD-SS patients have worse visual impairment, and they are more vulnerable to relapse than NMOSD-non SS patients, and the vision is lack of recovery for NMOSD-SS with recurrent eyes or the worst vision of onset less than 0.1.Immunosuppressive drugs can reduce the recurrence of NMOSD-SS relapse.

Further studies of the effects of aging on arginine metabolites in the rat vestibular nucleus and cerebellum

Some studies have demonstrated that aging is associated with impaired vestibular reflexes, especially otolithic reflexes, resulting in postural instability. However, the neurochemical basis of these age-related changes is still poorly understood. The l-arginine metabolic system has been implicated in changes in the brain associated with aging. In the current study, we examined the levels of l-arginine and its metabolizing enzymes and downstream metabolites in the vestibular nucleus complex (VNC) and cerebellum (CE) of rats with and without behavioral testing which were young (4months old), middle-aged (12months old) or aged (24months old). We found that aging was associated with lower nitric oxide synthase activity in the CE of animals with testing and increased arginase in the VNC and CE of animals with testing. l-citrulline and l-ornithine were lower in the VNC of aged animals irrespective of testing, while l-arginine and l-citrulline were lower in the CE with and without testing, respectively. In the VNC and CE, aging was associated with lower levels of glutamate in the VNC, irrespective of testing. In the VNC it was associated with higher levels of agmatine and putrescine, irrespective of testing. In the CE, aging was associated with higher levels of putrescine in animals without testing and with higher levels of spermine in animals with testing, and spermidine, irrespective of testing. Multivariate analyses indicated significant predictive relationships between the different variables, and there were correlations between some of the neurochemical variables and behavioral measurements. Cluster analyses revealed that aging altered the relationships between l-arginine and its metabolites. The results of this study demonstrate that there are major changes occurring in l-arginine metabolism in the VNC and CE as a result of age, as well as behavioral activity.

Abstract P4-08-01: IsomiRs and tRNA fragments are race-dependent regulators in breast cancer

This abstract was not presented at the symposium.

Roles of Chondrocytes in Endochondral Bone Formation and Fracture Repair

The formation of the mandibular condylar cartilage (MCC) and its subchondral bone is an important but understudied topic in dental research. The current concept regarding endochondral bone formation postulates that most hypertrophic chondrocytes undergo programmed cell death prior to bone formation. Under this paradigm, the MCC and its underlying bone are thought to result from 2 closely linked but separate processes: chondrogenesis and osteogenesis. However, recent investigations using cell lineage tracing techniques have demonstrated that many, perhaps the majority, of bone cells are derived via direct transformation from chondrocytes. In this review, the authors will briefly discuss the history of this idea and describe recent studies that clearly demonstrate that the direct transformation of chondrocytes into bone cells is common in both long bone and mandibular condyle development and during bone fracture repair. The authors will also provide new evidence of a distinct difference in ossification orientation in the condylar ramus (1 ossification center) versus long bone ossification formation (2 ossification centers). Based on our recent findings and those of other laboratories, we propose a new model that contrasts the mode of bone formation in much of the mandibular ramus (chondrocyte-derived) with intramembranous bone formation of the mandibular body (non-chondrocyte-derived).

[Programmed necrosis mediated by receptor-interacting protein 3: a new target for liver disease research]

Hepatocyte death mainly includes apoptosis and necrosis and is a critical process in the pathophysiological mechanism of liver injury caused by various reasons. Recent studies have shown that key regulatory molecules in the inhibition of apoptosis such as caspase cannot be used as targets for inhibiting disease progression in clinical practice. In recent years, programmed necrosis mediated by receptor-interacting protein 3(RIP3)becomes a new hot research topic. It not only plays an important role in inducing inflammatory response, but also is closely regulated by intracellular signal factors, and it is a type of active cell death which can be interfered with. Compared with apoptosis, programmed necrosis is accompanied by the release of various inflammatory factors, which significantly affects local immune microenvironment. RIP3-mediated programmed necrosis has been taken seriously in many diseases. Although its mechanism of action in liver disease remains unclear, the results of recent studies confirmed its important role in the development of liver disease. This article reviews the research advances in the role of RIP3-mediated programmed necrosis signaling pathway in liver disease of various causes and investigates the possibility of RIP3-mediated programmed necrosis as a new target in the treatment of liver disease.

Altered brain arginine metabolism in schizophrenia

Previous research implicates altered metabolism of l-arginine, a versatile amino acid with a number of bioactive metabolites, in the pathogenesis of schizophrenia. The present study, for we believe the first time, systematically compared the metabolic profile of l-arginine in the frontal cortex (Brodmann's area 8) obtained post-mortem from schizophrenic individuals and age- and gender-matched non-psychiatric controls (n=20 per group). The enzyme assays revealed no change in total nitric oxide synthase (NOS) activity, but significantly increased arginase activity in the schizophrenia group. Western blot showed reduced endothelial NOS protein expression and increased arginase II protein level in the disease group. High-performance liquid chromatography and liquid chromatography/mass spectrometric assays confirmed significantly reduced levels of γ-aminobutyric acid (GABA), but increased agmatine concentration and glutamate/GABA ratio in the schizophrenia cases. Regression analysis indicated positive correlations between arginase activity and the age of disease onset and between l-ornithine level and the duration of illness. Moreover, cluster analyses revealed that l-arginine and its main metabolites l-citrulline, l-ornithine and agmatine formed distinct groups, which were altered in the schizophrenia group. The present study provides further evidence of altered brain arginine metabolism in schizophrenia, which enhances our understanding of the pathogenesis of schizophrenia and may lead to the future development of novel preventions and/or therapeutics for the disease.

GPRC5A is a potential oncogene in pancreatic ductal adenocarcinoma cells that is upregulated by gemcitabine with help from HuR

GPRC5A is an orphan G-protein coupled receptor with an intriguing dual behavior, acting as an oncogene in some cancers and as a tumor suppressor in other cancers. In the pancreatic cancer context, very little is known about GPRC5A. By analyzing messenger RNA (mRNA) expression data from 675 human cancer cell lines and 10 609 samples from The Cancer Genome Atlas (TCGA) we found that GPRC5A's abundance in pancreatic cancer is highest (cell lines) or second highest (TCGA) among all tissues and cancer types. Further analyses of an independent set of 252 pancreatic normal and cancer samples showed GPRC5A mRNA to be more than twofold upregulated in primary tumor samples compared with normal pancreas (P-value<10⁻⁵), and even further upregulated in pancreatic cancer metastases to various organs (P-value=0.0021). Immunostaining of 208 cores (103 samples) of a tissue microarray showed generally low expression of GPRC5A protein in normal pancreatic ductal cells; on the other hand, in primary and metastatic samples, GPRC5A protein levels were dramatically increased in pancreatic ductal cells. In vitro studies of multiple pancreatic cancer cell lines showed that an increase in GPRC5A protein levels promoted pancreatic cancer cell growth and migration. Unexpectedly, when we treated pancreatic cancer cell lines with gemcitabine (2′,2′-difluorodeoxycytidine), we observed an increase in GPRC5A protein abundance. On the other hand, when we knocked down GPRC5A we sensitized pancreatic cancer cells to gemcitabine. Through further experimentation we showed that the monotonic increase in GPRC5A protein levels that we observe for the first 18 h following gemcitabine treatment results from interactions between GPRC5A's mRNA and the RNA-binding protein HuR, which is an established key mediator of gemcitabine's efficacy in cancer cells. As we discovered, the interaction between GPRC5A and HuR is mediated by at least one HuR-binding site in GPRC5A's mRNA. Our findings indicate that GPRC5A is part of a complex molecular axis that involves gemcitabine and HuR, and, possibly, other genes. Further work is warranted before it can be established unequivocally that GPRC5A is an oncogene in the pancreatic cancer context.

Further evidence that a variant of the gene NUDT15 may be an important predictor of azathioprine-induced toxicity in Chinese subjects: a case report

WHAT IS KNOWN AND OBJECTIVE

Thiopurine methyltransferase (TPMT) enzyme is an important component in the metabolism of azathioprine (AZA). Its mutation may lead to AZA-induced toxicity. The dysfunctional genetic variant TPMT *3C is of low frequency among Asians. Moreover, AZA-induced toxicity still occurs in some patients with normal TPMT activity. This suggests that additional factors, including other genetic variants, may contribute to such toxicity. Recent studies described a strong association between a variant of the NUDT15, a gene that mediates the hydrolysis of some nucleoside diphosphate derivatives, and thiopurine-related myelosuppression in Asians. We report the first case of a Chinese patient with AZA-induced severe toxicity with no clinically significant TPMT variant but with the NUDT15 c.415C>T allele.

CASE SUMMARY

A 40-year-old Chinese patient with PBC-AIH overlap syndrome had been receiving for one month, azathioprine (50 mg/day) and methylprednisolone (24 mg/day) based on his TPMT*3C wild-type genotype. The patient developed serious myelosuppression and hair loss. AZA was stopped, and the patient was given liver-protective drugs and supportive treatment. TPMT and NUDT15 gene sequencing suggests that NUDT15 c.415C>T mutation was the likely cause of the adverse reaction.

WHAT IS NEW AND CONCLUSION

NUDT15 c.415C>T may be another predictor of AZA-induced leukocytopenia. If further well-controlled studies validate this association with sufficient predictive power, NUDT15 and TPMT genotyping before starting AZA treatment may become appropriate.

Haploidentical, unmanipulated G-CSF-primed peripheral blood stem cell transplantation for high-risk hematologic malignancies: an update

Emerging data demonstrate promising results of related haploidentical allogeneic hematopoietic stem cell transplantation (haplo-HCT) for the treatment of hematologic malignancies. Data about G-CSF primed PBSC as reliable source of graft with myeloablative conditioning are lacking. We updated the outcomes in 130 adult patients with high-risk hematologic malignancies who received haplo-PBSC transplantation consecutively under busulfan-based conditioning. PBSC were freshly isolated and infused without ex vivo T-cell depletion into the recipients. Myeloid recovery was achieved in 99.2% patients with full donor chimerism. The cumulative incidence of acute grade 3-4 GvHD, overall and extensive chronic GvHD was 14.9%, 38.6% and 16.5%, respectively. The 3-year non-relapse mortality rate was 24.1%. Non-remission prior to transplant was associated with higher incidence of relapse (P=0.006), inferior overall survival (P=0.017) and leukemia-free survival (P=0.024). These data suggest that PBSC is a reliable graft source in haploidentical, unmanipulated transplant settings under myeloablative conditioning in patients with high-risk hematologic malignancies.

Relationship of hospital-associated bleeding with length of stay and total hospitalization costs in patients hospitalized for atrial fibrillation

BACKGROUND

While literature has focused on the impact of bleeding beginning outside the hospital setting among patients with atrial fibrillation (AF), there is little information regarding bleeding that first occurs within a hospital setting. This study was performed to determine the association between hospital-associated bleeding in patients admitted for AF on outcomes of length of stay (LOS) and total hospitalization cost.

METHODS AND RESULTS

The Premier research database was queried to identify adult inpatients discharged between 2008-2011 having a primary diagnosis code for AF where a bleeding diagnosis code was not present on admission. Regression was used to adjust for baseline differences in patients to estimate outcomes comparing patients with and without a hospital-associated bleed. There were 143,287 patients that met the study criteria. There were 2991 (2.1%) patients identified with a hospital associated bleed. After adjustment for covariates, the mean estimated LOS was significantly greater in the bleed group, at 6.0 days (95% CI = 5.8-6.1) vs the no bleed group at 3.3 days (95% CI = 3.3-3.3) (p < 0.0001). Similarly, the adjusted mean estimated total hospitalization cost was also significantly greater in the bleed group, $12,069 (95% CI = $11,779-$12,366) vs $6561 (95% CI = $6538-$6583) in the no bleed group (p < 0.0001).

CONCLUSIONS

After adjustments for baseline differences the data show that the 2.1% (n = 2991) of patients with hospital associated bleeding accounted for an estimated additional 8106 hospitalization days and $16.4 million dollars in cost over the study period compared to non-bleeders.

The trend of chemotherapy-induced peripheral neurotoxicity in ovarian cancer survivors and its impacts on daily life during and one year after treatment

PURPOSE

To explore the trend of progression and regression of peripheral neuropathy (PN) induced by combination of carboplatin and paclitaxel, and the impacts on daily activities.

MATERIALS AND METHODS

PN was evaluated by nurse-based interview and patient-reported measures in their diary. The severity of PN scaled by National Cancer Institute Common Toxicity Criteria (NCI-CTC) before each cycle of chemotherapy and at three, six, and 12 months after drug withdrawal and coded as Grade I - V.

RESULTS

The authors enrolled 106 eligible patients with ovarian cancer who underwent six cycles of combined chemotherapy of carboplatin plus paclitaxel. No patients showed Grade IV and V of PN and it was gradually aggravated following the dose accumulation. About 29.3% of the patients presented no PN, 64.2% Grade I, and 6.6% Grade II after the third course of chemotherapy, but increased to 36.8% of Grade I, 25.5% of Grade II, and 34.9% of Grade III after the sixth course of chemotherapy. At one-year follow-up, the rate of PN still existed with the rate of 88.5%, 57.3%, and 38.7% at three, six, and 12 months after drug withdrawal. Thirty-one patients encountered accidents, such as sharp injury (14.2%), fall (9.4%), burn (3.8%), and cold injury (1.9%).

CONCLUSIONS

A significant proportion of patients with epithelial ovarian cancer treated with carboplatin plus paclitaxel suffer long term neuropathy and it affects patient's daily activities. Specialized care is necessary to provide not only during treatment, but also months to years after drugs withdrawal.

The impact of ribavirin on real-world adherence rates in hepatitis C patients treated with sofosbuvir plus simeprevir

Background

Combination therapy with sofosbuvir (SOF) and simeprevir (SIM) is used to treat patients with hepatitis C virus infection. It is currently unknown whether adding ribavirin (RBV) to SOF + SIM, which raises the pill count from two up to eight pills a day, impacts adherence. The aim of this study is to examine the impact of pill count on real-world adherence rates in patients treated with SOF + SIM with and without RBV.

Methods

This retrospective study assessed composite adherence to SOF and SIM over 12 weeks of treatment for two cohorts of hepatitis C patients: one initiating SOF + SIM therapy, and the other initiating SOF + SIM + RBV therapy. Analyses were conducted using MarketScan^® and Optum US commercial pharmacy claims and enrollment data. Adherence was adjusted by treatment regimen, age, sex, co-pay, presence/absence of cirrhosis, treatment history, and Charlson Comorbidity Index.

Results

There was a significant difference in composite unadjusted and adjusted adherence rates for SOF and SIM for the SOF + SIM vs SOF + SIM + RBV cohorts based on MarketScan data (unadjusted, 92.6% and 89.7%, respectively; P=0.0423; adjusted, 92.2% and 88.7%, respectively; P=0.0176), but not based on Optum data (unadjusted, 94.8% and 95.6%, respectively; P=0.5618; adjusted, 94.8% and 95.1%, respectively; P=0.8589). In the MarketScan and Optum databases, there were no statistical differences in unadjusted and adjusted adherence rates for SOF. Unadjusted and adjusted adherence rates for SIM were mixed, as they were for composite adherence.

Conclusion

The impact of the addition of RBV to SOF + SIM therapy was mixed. The impact of RBV on SOF adherence was not significant in either database.

Hierarchical Nanofibrous Microspheres with Controlled Growth Factor Delivery for Bone Regeneration

The integration of controlled growth factor delivery and biomimetic architecture into a microsphere is a challenging but attractive strategy for developing new injectable biomaterials. In this work, a unique hierarchical nanosphere-encapsulated-in-microsphere scaffolding system is developed. First, heparin-conjugated gelatin (HG) is synthesized, which provides binding domains for bone morphogenetic protein 2 (BMP2) to stabilize this growth factor, protect it from denaturation and proteolytic degradation, and subsequently prolong its sustained release. Next, a unique approach is developed which includes a water-in-oil-in-oil double emulsion process and a thermally induced phase separation to encapsulate BMP2-binding HG nanospheres into nanofibrous microspheres. The nanofibrous microsphere is self-assembled from synthetic nanofibers, and has superior surface area, high porosity, low density, and is an excellent carrier to support cell adhesion and tissue in-growth. BMP2 in the hierarchical microsphere is released in a multiple-controlled manner by the binding with heparin and encapsulation of the nanosphere and microsphere. An in vivo calvarial defect model confirms that this microsphere is an excellent osteoinductive scaffold for enhanced bone regeneration. By choosing different growth factors, this hierarchical microsphere system can easily be applied to other types of tissue regeneration. The work expands the ability to develop new injectable biomaterials for advanced regenerative therapies.

Novel Polymorphisms of Adrenergic, Alpha-1B-, Receptor and Peroxisome Proliferator-activated Receptor Gamma, Coactivator 1 Beta Genes and Their Association with Egg Production Traits in Local Chinese Dagu Hens

Adrenergic, alpha-1B-, receptor (ADRA1B) and peroxisome proliferator-activated receptor gamma, coactivator 1 beta (PPARGC1B) genes are involved in regulation of hen ovarian development. In this study, these two genes were investigated as possible molecular markers associated with hen-housed egg production, egg weight (EW) and body weight in Chinese Dagu hens. Samples were analyzed using the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) technique, followed by sequencing analysis. Two novel single nucleotide polymorphisms (SNPs) were identified within the candidate genes. Among them, an A/G transition at base position 1915 in exon 2 of ADRA1B gene and a T/C mutation at base position 6146 in the 3′-untranslated region (UTR) of PPARGC1B gene were found to be polymorphic and named SNP A1915G and T6146C, respectively. The SNP A1915G (ADRA1B) leads to a non-synonymous substitution (aspartic acid 489-to-glycine). The 360 birds from the Dagu population were divided into genotypes AA and AG, allele A was found to be present at a higher frequency. Furthermore, the AG genotype correlated with significantly higher hen-housed egg production (HHEP) at 30, 43, 57, and 66 wks of age and with a higher EW at 30 and 43 wks (p<0.05). For the SNP T6146C (PPARGC1B), the hens were typed into TT and TC genotypes, with the T allele shown to be dominant. The TC genotype was also markedly correlated with higher HHEP at 57 and 66 wks of age and EW at 30 and 43 wks (p<0.05). Moreover, four haplotypes were reconstructed based on these two SNPs, with the AGTC haplotype found to be associated with the highest HHEP at 30 to 66 wks of age and with higher EW at 30 and 43 wks (p<0.05). Collectively, the two SNPs identified in this study might be used as potential genetic molecular markers favorable in the improvement of egg productivity in chicken breeding.

Region-specific changes in presynaptic agmatine and glutamate levels in the aged rat brain

During the normal aging process, the brain undergoes a range of biochemical and structural alterations, which may contribute to deterioration of sensory and cognitive functions. Age-related deficits are associated with altered efficacy of synaptic neurotransmission. Emerging evidence indicates that levels of agmatine, a putative neurotransmitter in the mammalian brain, are altered in a region-specific manner during the aging process. The gross tissue content of agmatine in the prefrontal cortex (PFC) of aged rat brains is decreased whereas levels in the temporal cortex (TE) are increased. However, it is not known whether these changes in gross tissue levels are also mirrored by changes in agmatine levels at synapses and thus could potentially contribute to altered synaptic function with age. In the present study, agmatine levels in presynaptic terminals in the PFC and TE regions (300 terminals/region) of young (3month; n=3) and aged (24month; n=3) brains of male Sprague-Dawley rats were compared using quantitative post-embedding immunogold electron-microscopy. Presynaptic levels of agmatine were significantly increased in the TE region (60%; p<0.001) of aged rats compared to young rats, however no significant differences were detected in synaptic levels in the PFC region. Double immunogold labeling indicated that agmatine and glutamate were co-localized in the same synaptic terminals, and quantitative analyses revealed significantly reduced glutamate levels in agmatine-immunopositive synaptic terminals in both regions in aged rats compared to young animals. This study, for the first time, demonstrates differential effects of aging on agmatine and glutamate in the presynaptic terminals of PFC and TE. Future research is required to understand the functional significance of these changes and the underlying mechanisms.

Association of novel polymorphisms of forkhead box L2 and growth differentiation factor-9 genes with egg production traits in local Chinese Dagu hens

Transcription factor forkhead box L2 (FOXL2) and growth differentiation factor-9 (GDF9) genes have critical roles in the regulation of hen ovarian development. In the present study, these genes were explored as possible molecular markers associated with BW, hen-housed egg production, and egg weight in Chinese Dagu hens. Samples were analyzed using the PCR-single strand conformation polymorphism (PCR-SSCP) technique followed by sequencing analysis, and two novel single nucleotide polymorphisms (SNPs) were identified within these candidate genes. Among them, an A/G transition at base position 238 in the coding region of the FOXL2 gene and a G/T transversion at base position 1609 in exon 2 of the GDF9 gene were found to be polymorphic and named SNPs A238G and G1609T, respectively. The SNP A238G (FOXL2) leads to a nonsynonymous substitution (isoleucine77-to-valine), and when the 360 Dagu hen samples were divided into genotypes AA and AB, allele A was found to be present at a higher frequency. Furthermore, the AA genotype correlated with significantly higher hen-housed egg production at 30, 43, 57, and 66 wk of age and with a higher egg weight at 43 wk (P<0.05). For the SNP G1609T (GDF9), the hens were typed into TT and TC genotypes, with the T allele shown to be dominant. The TC genotype was also markedly correlated with higher hen-housed egg production and a higher egg weight (P<0.05). Moreover, four haplotypes were reconstructed based on these two SNPs, with the AATC haplotype found to be correlated with the highest hen-housed egg production at 30 to 66 wk of age and with higher egg weights at 43 wk (P<0.05). Collectively, the two SNPs identified in this study might be used as possible genetic molecular markers to aid in the improvement of egg production traits in chicken breeding.