Ureteral tunnel length versus ureteral orifice configuration in the determination of ureterovesical junction competence: A computer simulation model

INTRODUCTION

The long-held belief that a ureteral re-implant tunnel should be five times the diameter of the ureter, as proposed by Paquin in 1959, ignores the effect of the orifice on the occurrence of reflux. In 1969, Lyon proposed that the shape of the ureteral orifice (UO) is more important than the intravesical tunnel. However, both theories missed quantitative evidence from principles of physics. The goal of the current study was to test Lyon's theory through numerical models (i.e. to quantify the sensitivity of ureterovesical junction (UVJ) competence to intravesical tunnel length and to the UO).

MATERIALS AND METHODS

The closure of a three-dimensional spatial configuration of ureter, constrained within a bladder, was simulated. Two common UO shapes (i.e. golf type vs 2-mm volcano type (Summary Fig.)), and two different intravesical ureteral tunnel length/diameter ratios (3:1 and 5:1) were examined. The required closure pressures were then compared.

RESULTS

The UO was a significant factor in determining closure pressure. Given the same intravesical ureteral tunnel length/diameter ratio, the required closure pressure for the volcanic orifice was 78% less than that for the golf orifice. On the other hand, the intravesical ureteral tunnel length/diameter ratio had minimal effect on the required closure pressure. As the intravesical ureteral tunnel length/diameter ratio changed from 3:1 to 5:1, the required closure pressure was reduced by less than 7%, regardless of the orifice shape.

CONCLUSIONS

The simulation results showed that UVJ competence was more sensitive to a 2-mm protrusion of the UO compared to an increase in the intravesical tunnel length from 3:1 to 5:1. This agrees with Lyon's theory, and at the same time challenges Paquin's 5:1 rule. Researchers could use this information to consider the UO configuration in further animal, human, computer or material models.

[The treatment effect of eustachian tube atresia with laser and connical plastic tube after radiotherapy for nasopharyngeal carcinoma]

Objective: To investigate the method in treatment of Eustschian tube atresia caused by radiotherapy. Methods: Two cases diagnosed of Eustschian tube atresia following radiotherapy were retrospectively analyzed in Department of Otorhinolaryngology, Divided Hospital of Shanghai University Communication Affiliated First People Hospital in Apr. 2014 and Oct. 2015. Both cases were female, 65 and 64 years old, and accepted radiotherapy six and 20 years ago respectively. The pharyngeal orifices of Eustschian tube were found to be totally closed under endoscope. The closed Eustschian tubes were re-opened by laser and re-shaped by a slim and conical plastic tube for more than six months. They were followed up and evaluated over 12 months. Results: At six and 12 months after treatment, round mouths were formed in the pharyngeal orifice of Eustachian tube, and the patients had no resistance in Valsalva's test. No shrink or abnormal opening of orifice was found at follow-up of 20 and 12 months. Conclusion: The method of re-opening by laser and re-shaping by a slim and conical plastic tube is recommended to treat Eustschian tube occlusion caused by radiotherapy.

Rare DNA variants in the brain-derived neurotrophic factor gene increase risk for attention-deficit hyperactivity disorder: a next-generation sequencing study

Attention-deficit hyperactivity disorder (ADHD) is a prevalent and highly heritable disorder of childhood with negative lifetime outcomes. Although candidate gene and genome-wide association studies have identified promising common variant signals, these explain only a fraction of the heritability of ADHD. The observation that rare structural variants confer substantial risk to psychiatric disorders suggests that rare variants might explain a portion of the missing heritability for ADHD. Here we believe we performed the first large-scale next-generation targeted sequencing study of ADHD in 152 child and adolescent cases and 188 controls across an a priori set of 117 genes. A multi-marker gene-level analysis of rare (<1% frequency) single-nucleotide variants (SNVs) revealed that the gene encoding brain-derived neurotrophic factor (BDNF) was associated with ADHD at Bonferroni corrected levels. Sanger sequencing confirmed the existence of all novel rare BDNF variants. Our results implicate BDNF as a genetic risk factor for ADHD, potentially by virtue of its critical role in neurodevelopment and synaptic plasticity.

Uncovering the spatial heterogeneity of Ediacaran carbon cycling

Records of the Ediacaran carbon cycle (635-541 million years ago) include the Shuram excursion (SE), the largest negative carbonate carbon isotope excursion in Earth history (down to -12‰). The nature of this excursion remains enigmatic given the difficulties of interpreting a perceived extreme global decrease in the δ¹³ C of seawater dissolved inorganic carbon. Here, we present carbonate and organic carbon isotope (δ¹³ C_carb and δ¹³ C_org ) records from the Ediacaran Doushantuo Formation along a proximal-to-distal transect across the Yangtze Platform of South China as a test of the spatial variation of the SE. Contrary to expectations, our results show that the magnitude and morphology of this excursion and its relationship with coexisting δ¹³ C_org are highly heterogeneous across the platform. Integrated geochemical, mineralogical, petrographic, and stratigraphic evidence indicates that the SE is a primary marine signature. Data compilations demonstrate that the SE was also accompanied globally by parallel negative shifts of δ³⁴ S of carbonate-associated sulfate (CAS) and increased ⁸⁷ Sr/⁸⁶ Sr ratio and coastal CAS concentration, suggesting elevated continental weathering and coastal marine sulfate concentration during the SE. In light of these observations, we propose a heterogeneous oxidation model to explain the high spatial heterogeneity of the SE and coexisting δ¹³ C_org records of the Doushantuo, with likely relevance to the SE in other regions. In this model, we infer continued marine redox stratification through the SE but with increased availability of oxidants (e.g., O₂ and sulfate) limited to marginal near-surface marine environments. Oxidation of limited spatiotemporal extent provides a mechanism to drive heterogeneous oxidation of subsurface reduced carbon mostly in shelf areas. Regardless of the mechanism driving the SE, future models must consider the evidence for spatial heterogeneity in δ¹³ C presented in this study.

[Comparison of intensified myeloablative conditioning regime without antithymocytic globulin (ATG) with myeloablative conditioning regime for single-unit unrelated umbilical cord blood transplantation in hematological malignancies]

OBJECTIVE

To campare the effect and tolerance beween intensified myeloablative conditioning regime (IMCR) without antithymocyte globulin (ATG) and myeloablative conditioning regime (MCR) for single-unit unrelated umbilical cord blood transplantation (sUCBT) in hematological malignancies.

METHODS

The clinical data of 190 patients with hematological malignancies undergoing sUCBT between April 2000 and December 2013 at Department of Hematology, Anhui Provincial Hospital were retrospectively analyzed, of whom 156 received IMCR without ATG (IMCR group), including 79 patient receiving total body irradiation (TBI)/cytosine arabinoside (Ara-C)/cyclophosphamide (CY) regime, 47 receiving fludarabine (Flu)/busulfan (Bu)/CY regime, and 30 receiving Ara-C/Bu/CY regime, and all of the 156 received a combination of cyclosporine A (CsA) and mycophelonate mofetil (MMF) for the prophylaxis of graft-versus-host disease (GVHD); the remaining 34 patients received MCR (MCR group), 30 patients receiving Bu/CY regime, and 4 receiving TBI/CY regime, all using CsA/MMF±ATG or methotrexate (MTX) for the prophylaxis of GVHD. The two groups were compared in disease status at the time of transplantation, characteristics of graft, transplantation effect, and transplantation-related complications.

RESULTS

There were no statistically significant differences between the two groups in gender, disease type, human leukocyte antigen match, ABO blood type match, and disease status at the time of transplantation (all P>0.05). The median age and body weight at transplantation in the IMCR group were significantly higher than those in the MCR group (13 years vs 9 years, P=0.003; 44 kg vs 26 kg, P=0.000). The median doses of infused total nucleated cells (×10(7)/kg) and CD34(+) cells (×10(5)/kg) in the IMCR group were significantly lower than in the MCR group (3.87 vs 4.99, P=0.002; 2.00 vs 3.17, P=0.000). The cumulative incidence of myeloid engraftment on the 42th day and platelet engraftment on the 120th day in the IMCR group were remarkably higher than in the MCR group [96.33%(95%CI: 96.27%-96.39%)vs 82.30%(95%CI: 80.67%-83.93%), P=0.000; 86.44%(95%CI: 86.28%-86.60%)vs 51.17%(95%CI: 49.02%-53.32%), P=0.002]. There were no statistically significant differences in the incidences of grade Ⅱ to Ⅳ acute GVHD, grade Ⅲ to Ⅳ acute GVHD, and 2-year chronic GVHD(P=0.482, 0.928, 0.579). The incidence of pre-engraftment syndrome in the IMCR group was higher than in the MCR group(82.70% vs 47.06%, P=0.000). And 180-day transplantation-related mortality (TRM) in the IMCR group was lower than that in the MCR group [20.50%(95%CI: 20.28%-20.71%)vs 42.20% (95%CI: 41.32%-45.09%), P=0.004]. Up to October 2015, with a median follow-up of 44.2(22.7-188.9)months, the estimated 3-year overall survival and disease-free survival in the IMCR group were both significantly higher than those in the MCR group (62.90% vs 34.10%, P=0.000; 58.60% vs 34.10%, P=0.001).

CONCLUSION

IMCR without ATG may improve the engraftment without increasing complications, reduce early transplantation-related mortality, and improve survival.

[Autosomal dominant hearing loss resulting from mutation in the GJB2 gene:nonsyndromic presentation in a Chinese family]

Objective:To investigate the genotype, phenotype and genetic features. The mutations in GJB2, GJB3, GJB6, SLC26A4 genes, 12SrRNA and tRNASer(UCN) were tested in a Chinese family with autosomal dominant nonsyndromic hearing loss. Method:Blood samples and clinical data of the proband and her partial family members were collected. DNA was extracted from the blood samples. The GJB2, GJB3, GJB6, SLC26A4 genes, 12SrRNA and tRNASer(UCN) mutations were analyzed by polymerase chain reaction(PCR) and direct sequencing. Result:Heterozygous mutation of GJB2 R75Q was identified in the proband and her mother. No mutation of other testing genes was detected. Conclusion:The R75Q mutation of the GJB2 gene cause autosomal dominant nonsyndromic deafness in the proband and her mother. Children can inherit the R75Q mutation from their parents, so the results of gene testing will be helpful for further guidance of procreation.

Impact of P2RX7 ablation on the morphological, mechanical and tissue properties of bones in a murine model of duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is an inherited, lethal disorder characterised by progressive muscle degeneration and associated bone abnormalities. We have previously demonstrated that P2RX7 purinergic receptors contribute to the pathogenesis of DMD, and found that P2RX7 ablation alleviated the severity of the disease. In this work we have used a dystrophic mdx mouse crossed with the global P2RX7 receptor to generate a knockout mouse (mdx/P2X7^-/-), and compared its morphometric, mechanical and tissue properties against those of mdx, as well as the wild type (WT) and the P2RX7 knockout (P2X7^-/-). Micro-computed tomography (µCT), three-point bending testing, scanning electron microscopy (SEM) and nano-indentation were utilised in the study. The bones were analysed at approximately 4 weeks of age to examine the impact of P2RX7 ablation on the bone properties during the acute disease phase, before muscle wasting is fully developed. The results show that P2RX7 purinoceptor ablation has produced improvement or significant improvement in some of the morphological, the mechanical and the tissue properties of the dystrophic bones examined. Specifically, although the ablation produced smaller bones with significantly lower total cross-section area (Tt.Ar) and Second Moment of Area (SMA), significantly higher cortical bone area (Ct.Ar), cortical area fraction (Ct.Ar/Tt.Ar) and trabecular bone volume fraction (BV/TV) are found in the mdx/P2X7^-/- mice than in any other types. Further, the mdx/P2X7^-/- bones have relatively higher average flexural strength, work-to-fracture and significantly higher strain to failure compared with those of mdx, suggesting greater resistance to fracture. Indentation modulus, elasticity and creep are also significantly improved in the knockout cortical bones over those of mdx. These findings seem to suggest that specific pharmacological blockade of P2RX7 may improve dystrophic bones, with a potential for therapeutic application in the treatment of the disease.

Multidetector computed tomography for detecting left atrial/left atrial appendage thrombus: a meta-analysis

BACKGROUND

The diagnostic accuracy of multidetector computed tomography (MDCT) in the detection of left atrial/left atrial appendage (LA/LAA) thrombus had been tested in many studies; however, the results are controversial.

AIM

The aim of the present study was to evaluate synthetically the diagnostic accuracy of MDCT in LA/LAA thrombus.

METHODS

PubMed and Embase were searched for published prospective studies which compared computed tomography with transoesophageal echocardiography (TEE) in detecting LA/LAA thrombus prior to March 2014. Descriptive and quantitative information was extracted and MetaDiSc 1.4 was used to perform a meta-analysis.

RESULTS

Fifteen prospective clinical controlled trials with 2540 patients fulfilled the inclusion criteria. The pooled sensitivities (SEN): 0.957; pooled specificities (SPE): 0.917; pooled positive likelihood ratio (PLR): 22.017; pooled negative likelihood ratio (NLR): 0.060; pooled diagnostic odds ratio (DOR): 437.43; the area under the curve (AUC): 0.9883; Q*-value: 0.9544. However, in the abovementioned indexes, the heterogeneities were statistically significant between studies (P < 0.05, inconsistency index (I(2) ) > 50%). In a sub-analysis of studies in which delayed imaging, electrocardiogram (ECG) gating and heart rate control were performed, not only the diagnostic accuracy, but also the heterogeneities were significantly improved (pooled SEN 0.991; pooled SPE 0.989; pooled PLR 60.768; pooled NLR 0.034; pooled DOR 2561.7; AUC 0.9972; Q*-value 0.9806; all the indexes' P-value were greater than 0.05 and the I(2) were 0%, except for SPE, I(2) = 54.6%).

CONCLUSION

For patients with TEE intolerance or contraindications, MDCT may be an alternative method, especially when the delayed imaging, ECG gating and heart rate control were performed.

Activation and dynamic expression of Notch signalling in dental pulp cells after injury in vitro and in vivo

AIM

To investigate the expression pattern of Notch signalling in odontoblast-like cells stimulated by lipopolysaccharide (LPS) in vitro, and in injured rat dental pulp in vivo.

METHODOLOGY

Mouse odontoblast-like cells (MDPC-23) were exposed to LPS. Expression of Notch-related genes was detected by real-time PCR. A rat pulpitis model was established by mechanical injury and LPS plus mechanical injury was followed by the analysis of expression of Notch2 by immunohistochemical staining. One-way analysis of variance (anova) was performed to examine the effect of differing concentrations of LPS on cell proliferation, and least significant difference test was used for paired comparisons. For independent sample, t-test was performed to compare the expression of Notch signalling genes between LPS group and control group in vitro.

RESULTS

The in vitro study revealed the proliferation of MDPC-23 cells on exposure to 10 ng mL^-1 to 1 μg mL^-1 LPS. Expression of Notch1 and Notch2 was significantly higher in the LPS group than that in the control group on day 1 and day 3 (P ˂ 0.05). The levels of both Delta1 and Jagged1 were higher in the study group than in the control group on day 3 (P = 0.019 and P = 0.034) and day 5 (P ˂ 0.001 and P = 0.046), respectively. In addition, Hes1 levels were significantly higher in the study group than in the control group on day 5 (P = 0.005). The in vivo study demonstrated positive staining for Notch2, both in the mechanical injury (MI) group and in the LPS plus mechanical injury (LMI) group from day 3 to day 7, which showed very weak or absent staining on day 14, thereby demonstrating the dynamic nature of the change.

CONCLUSIONS

Both in vitro and in vivo activation and dynamic expression of Notch signalling in dental pulp cells after injury were found. Notch signalling activation by LPS stimulation or mechanical injury showed a similar pattern in vivo.

A myeloablative conditioning regimen with fludarabine demonstrates good results in UCBT for 30 pediatric patients with hematologic malignancies, especially acute lymphoblastic leukemia

We retrospectively analyzed the safety and efficacy of a myeloablative conditioning regimen with fludarabine (FLU) in unrelated cord blood transplantation (UCBT) of 30 pediatric patients with hematologic malignancies. The conditioning regimen consisted of FLU, busulfan (BU) and cyclophosphamide (CY). All of the patients received Cyclosporine (CSA) and mycophenolate mofetil (MMF) as graft versus host disease (GVHD) prophylaxis. We achieved high engraftment rates (96.7%) and rapid hematopoietic reconstitution. Acute GVHD occurred in 12 cases of the 29 engraftment patients (41.4%), and 6 cases (20.7%) were of grade III-IV. Chronic GVHD only occurred in 1 of 28 evaluable patients (3.6%). Twenty-three patients (76.7%) became infected, and 3 cases (10.0%) died of severe infections. Cytomegalovirus (CMV) reactivation occurred in 70.0% of the patients, but no CMV diseases were observed, nor did any patients die of CMV infection. The cumulative incidence of relapse (6.7%) was significantly reduced, and none of the acute lymphoblastic leukemia (ALL) patients relapsed. The 3-year overall survival (OS) and event-free survival (EFS) rates were 73.3% and 70.0%, respectively. The 3-year OS and EFS of the ALL patients was 75.0%. This conditioning regimen demonstrates good results and security in UCBT, especially in acute lymphoblastic leukemia.