Biomechanical study of a new rim plate fixation strategy for two kinds of posterolateral depression patterns of tibial plateau fractures: a finite element analysis.

PURPOSE: The biomechanical capacity of "Barrel Hoop Plate (BHP)" in the treatment of the posterolateral tibial plateau (PL) depression fractures remains unknown. In this study, two kinds of posterolateral tibial plateau depression models involving mild slope-type depression fracture (MSDF) and local sink hole-type depression fracture (LSDF) were created to test and compare the biomechanical capacities of BHP with the other two conventional fixations (Anterolateral Plate and Posterolateral Plate, ALP and PLP) by finite element analysis. METHODS: The 3D models of three kinds of plate-screw systems and the two kinds of PL-depression models (MSDF and LSDF) were created. An axial force of 400N was applied from the distal femur to the tibial plateau. The maximal displacements of the posterolateral fractures (PLFs), the distribution on the PLFs articular surface and key points displacements were measured. Stresses in the fixation complex including the maximal Equivalent (von-Mises) Stress of implants, the max shear stress of PLFs and stiffness of the fixation were calculated. RESULTS: The maximal displacement of MSDF was least in Group BHP. The maximal displacement of LSDF was least in Group ALP. In MSDF, BHP showed the best rim fix effect in MSDF, but unsatisfactory results in LSDF. In both MSDF and LSDF, the greatest max Equivalent Stress of the plate and the screw occurred in the PLP system. ALP and BHP showed a comparable stiffness in MSDF and ALP had the strongest stiffness in the fixation of LSDF. CONCLUSIONS: In MSDF, the BHP has the best biomechanical capacity, especially in displacements of key points such as the PL rim, fracture line, and depression center. In LSDF, the ALP system shows the best biomechanical effect. Although the PLP has the best fixation effect on the posterior wall, it is not suitable for PL-depression fracture fixation.

RNF13 protects against pathological cardiac hypertrophy through p62-NRF2 pathway.

Heart failure (HF) severely impairs human health because of its high incidence and mortality. Cardiac hypertrophy is the main cause of HF, while its underlying mechanism is not fully clear. As an E3 ubiquitin ligase, Ring finger protein 13 (RNF13) plays a crucial role in many disorders, such as liver immune, neurological disease and tumorigenesis, whereas the function of RNF13 in cardiac hypertrophy remains largely unknown. In the present study, we found that the protein expression of RNF13 is up-regulated in the transverse aortic constriction (TAC)-induced murine hypertrophic hearts and phenylephrine (PE)-induced cardiomyocyte hypertrophy. Functional investigations indicated that RNF13 global knockout mice accelerates the degree of TAC-induced cardiac hypertrophy, including cardiomyocyte enlargement, cardiac fibrosis and heart dysfunction. On the contrary, adeno-associated virus 9 (AAV9) mediated-RNF13 overexpression mice alleviated cardiac hypertrophy. Furthermore, we demonstrated that adenoviral RNF13 attenuates the PE-induced cardiomyocyte hypertrophy and down-regulates the expression of cardiac hypertrophic markers, while the opposite results were observed in the RNF13 knockdown group. The RNA-sequence of RNF13 knockout and wild type mice showed that RNF13 deficiency activates oxidative stress after TAC surgery. In terms of the mechanism, we found that RNF13 directly interacted with p62 and promoted the activation of downstream NRF2/HO-1 signaling. Finally, we proved that p62 knockdown can reverse the effect of RNF13 in cardiac hypertrophy. In conclusion, RNF13 protects against the cardiac hypertrophy via p62-NRF2 axis.

Comparison of modified gunsight suture technique and traditional interrupted suture in enterostomy closure.

BACKGROUND: Prophylactic enterostomy surgery is a common surgical approach used to reduce the risk of anastomotic leakage in patients who have undergone partial intestinal resection due to trauma or tumors. However, the traditional interrupted suturing technique used in enterostomy closure surgery has several issues, including longer surgical incisions and higher incision tension, which can increase the risk of postoperative complications. To address these issues, scholars have proposed the use of a "gunsight suture" technique. This technique involves using a gunsight incision instead of a traditional linear incision, leaving a gap in the center for the drainage of blood and fluid to reduce the risk of infection. Building on this technique, we propose an improved gunsight suture technique. A drainage tube is placed at the lowest point of the incision and close the gap in the center of the gunsight suture, which theoretically facilitates early postoperative mobility and reduces the burden of dressing changes, thereby reducing the risk of postoperative complications. AIM: To compare the effectiveness of improved gunsight suture technique with traditional interrupted suture in closing intestinal stomas. METHODS: In this study, a retrospective, single-center case analysis was conducted on 270 patients who underwent prophylactic ileostomy closure surgery at the Department of Colorectal Surgery of Qilu Hospital from April 2017 to December 2021. The patients were divided into two groups: 135 patients received sutures using the improved gunsight method, while the remaining 135 patients were sutured with the traditional interrupted suture method. We collected data on a variety of parameters, such as operation time, postoperative pain score, body temperature, length of hospital stays, laboratory indicators, incidence of incisional complications, number of wound dressing changes, and hospitalization costs. Non-parametric tests and chi-square tests were utilized for data analysis. RESULTS: There were no statistically significant differences in general patient information between the two groups, including the interval between the first surgery and the stoma closure [132 (105, 184) d vs 134 (109, 181) d, P = 0.63], gender ratio (0.64 vs 0.69, P = 0.44), age [62 (52, 68) years vs 60 (52, 68) years, P = 0.33], preoperative body mass index (BMI) [23.83 (21.60, 25.95) kg/m² vs 23.12 (20.94, 25.06) kg/m², P = 0.17]. The incidence of incision infection in the improved gunsight suture group tended to be lower than that in the traditional interrupted suture group [ (n = 2/135, 1.4%) vs (n = 10/135, 7.4%), P < 0.05], and the postoperative hospital stay in the improved gunsight suture group was significantly shorter than that in the traditional interrupted suture group [5 (4, 7) d vs 7 (6, 8) d, P < 0.05]. Additionally, the surgical cost in the modified gunsight suture group was slightly lower than that in the traditional suture group [4840 (4330, 5138) yuan vs 4980 (4726, 5221) yuan, P > 0.05], but there was no significant difference in the total hospitalization cost between the two groups. CONCLUSION: In stoma closure surgery, the improved gunsight technique can reduce the incision infection rate, shorten the postoperative hospital stay, reduce wound tension, and provide better wound cosmetic effects compared to traditional interrupted suture.

Imaging Features and Risk Factors of Pancreatic Cystic Lesions Complicating Autoimmune Pancreatitis: A Retrospective Study.

OBJECTIVE: This study aimed to explore the imaging features and risk factors of PCLs complicating AIP, and investigate its prognosis through continuous imaging follow-up. PATIENTS AND METHODS: Patients who were diagnosed with AIP from January 2014 to December 2020 in our hospital were recruited. We analyzed the CT and MRI features of PCLs complicating AIP, and investigated its prognosis through imaging follow-up. We also compared subjects with and without PCLs using clinical, laboratory, and imaging data; the related risk factors associated with PCLs were investigated in a multivariate logistic regression analysis. RESULTS: In this group, 16 patients had PCLs and 86 did not. A total of 43 PCLs larger than 5mm were found in 15 patients. Among these PCLs, 35 showed homogeneous signal (density); one, bleeding; three, linear separation; and four, small focal low signal on T2WI. Eight patients with 23 PCLs appeared for the follow-up after steroid treatment. Short-term follow-up showed that 11 PCLs disappeared, nine reduced, one unchanged and two enlarged. Of the 12 PCLs that did not disappear, 10 PCLs disappeared at long-term follow-up, except for two reduced PCLs were not re-examined. Logistic regression analysis showed that drinking history was an independent risk factor, age ≥ 65 years was an independent protective factor for PCLs complicating AIP. CONCLUSION: The imaging features of PCLs complicating AIP are various, which can be single or multiple, most of them are homogeneous, and some lesions may be accompanied by hemorrhage, separation and necrosis. Age ≥ 65 years and avoiding drinking may help to reduce the occurrence of these lesions.

Lysosomal-Associated Transmembrane Protein 5 Promotes Proliferation, Migration, and Invasion of Clear Cell Renal Cell Carcinoma.

Clear cell renal cell carcinoma (ccRCC) is the most aggressive and deadly cancer of the urinary system and is regulated by multiple signaling pathways. However, the specific molecular mechanisms underlying ccRCC have not been fully studied or demonstrated. This study aimed to elucidate the function of lysosomal-associated transmembrane protein 5 (LAPTM5) in ccRCC cell lines and animal models and determine the potential underlying mechanisms. Our results demonstrated that LAPTM5 expression in patients with ccRCC was significantly higher in the tumor group than that in the adjacent nontumor group. Moreover, LAPTM5 promoted proliferation, migration, and invasion of ccRCC cells through the gain and loss of the function of LAPTM5 in 786-0 and Caki-1 cell lines. Similar results regarding LAPTM5 overexpression were obtained in BALB/c nude mice. In addition, LAPTM5 activated the Jun N-terminal kinase (JNK)/p38 signaling cascade by interacting with Ras-related C3 botulinum toxin substrate 1 (RAC1). Treatment with an RAC1 inhibitor eliminated the effects of LAPTM5 in ccRCC. In conclusion, these results indicate that LAPTM5 may be a new therapeutic target for ccRCC via activation of the RAC1-JNK/p38 axis.

Tumor Suppressive Role of MUC6 in Wilms Tumor via Autophagy-Dependent ß-Catenin Degradation.

Wilms tumor is the most common renal malignancy in children. Known gene mutations account for about 40% of all wilms tumor cases, but the full map of genetic mutations in wilms tumor is far from clear. Whole genome sequencing and RNA sequencing were performed in 5 pairs of wilms tumor tissues and adjacent normal tissues to figure out important genetic mutations. Gene knock-down, CRISPR-induced mutations were used to investigate their potential effects in cell lines and in-vivo xenografted model. Mutations in seven novel genes (MUC6, GOLGA6L2, GPRIN2, MDN1, MUC4, OR4L1 and PDE4DIP) occurred in more than one patient. The most prevalent mutation was found in MUC6, which had 7 somatic exonic variants in 4 patients. In addition, TaqMan assay and immunoblot confirmed that MUC6 expression was reduced in WT tissues when compared with control tissues. Moreover, the results of MUC6 knock-down assay and CRISPR-induced MUC6 mutations showed that MUC6 inhibited tumor aggression via autophagy-dependent ß-catenin degradation while its mutations attenuated tumor-suppressive effects of MUC6. Seven novel mutated genes (MUC6, GOLGA6L2, GPRIN2, MDN1, MUC4, OR4L1 and PDE4DIP) were found in WT, among which MUC6 was the most prevalent one. MUC6 acted as a tumor suppressive gene through autophagy dependent ß-catenin pathway.

Role of GALNT4 in protecting against cardiac hypertrophy through ASK1 signaling pathway.

Pathological myocardial hypertrophy is regulated by multiple pathways. However, its underlying pathogenesis has not been fully explored. The goal of this work was to elucidate the function of polypeptide N-acetylgalactosaminyltransferase 4 (GALNT4) in myocardial hypertrophy and its underlying mechanism of action. We illustrated that GALNT4 was upregulated in the models of hypertrophy. Two cardiac hypertrophy models were established through partial transection of the aorta in GALNT4-knockout (GALNT4-KO) mice and adeno-associated virus 9-GALNT4 (AAV9-GALNT4) mice. The GALNT4-KO mice demonstrated accelerated cardiac hypertrophy, dysfunction, and fibrosis, whereas the opposite phenotype was observed in AAV9-GALNT4 mice. Similarly, GALNT4 overexpression mitigated the degree of phenylephrine-induced cardiomyocyte hypertrophy in vitro whereas GALNT4 knockdown aggravated the hypertrophy. In terms of mechanism, GALNT4 deficiency increased the phosphorylation and activation of ASK1 and its downstream targets (JNK and p38), whereas GALNT4 overexpression inhibited activation of the ASK1 pathway. Furthermore, we demonstrated that GALNT4 can directly bind to ASK1 inhibiting its N-terminally mediated dimerization and the subsequent phosphorylation of ASK1. Finally, an ASK1 inhibitor (iASK1) was able to reverse the effects of GALNT4 in vitro. In summary, GALNT4 may serve as a new regulatory factor and therapeutic target by blocking the activation of the ASK1 signaling cascade.

Smart deworming collar: A novel tool for reducing Echinococcus infection in dogs.

Echinococcosis is a serious zoonotic parasitic disease transmitted from canines to humans and livestock. Periodic deworming is recommended by the WHO/OIE as a highly effective measure against echinococcosis. However, manual deworming involves significant challenges, particularly in remote areas with scarce resources. The insufficient awareness delivering praziquantel (PZQ) baits for dogs leads to low compliance rate. The aim of this study was therefore to develop a novel smart collar for dogs to address these challenges. We developed a smart Internet of Things (IoT)-based deworming collar which can deliver PZQ baits for dogs automatically, regularly, quantitatively with predominant characteristics of being waterproof, anti-collision, cold-proof and long life battery. Its performance was tested in two remote locations on the Tibetan Plateau. A cross-sectional survey was conducted to evaluate the compliance of the dog owners. Further, a randomized controlled study was performed to evaluate the difference between smart-collar deworming and manual deworming. The collar's effectiveness was further assessed on the basis of Generalized Estimation Equations (GEE). The testing and evaluation was done for 10 smart deworming collars in factory laboratory, 18 collars attached for 18 dogs in Seni district, Tibet Autonomous Region, China, and 523 collars attached for 523 dogs in Hezuo city, Gansu province, China. The anti-collision, waterproof, and coldproof proportion of the smart collars were 100.0%, 99.5%, and 100.0%, respectively. When compared to manual deworming, the dogs' risk of infection with Echinococcus on smart-collar deworming is down to 0.182 times (95% CI: 0.049, 0.684) in Seni district and 0.355 (95%CI: 0.178, 0.706) in Hezuo city, the smart collar has a significant protective effect. The owners' overall compliance rate to attach the smart collars for their dogs was 89%. The smart deworming collar could effectively reduce the dogs' risk of infection with Echinococcus in dogs, significantly increase the deworming frequency and coverage and rapidly remove worm biomass in dogs. Thus, it may be a promising alternative to manual deworming, particularly in remote areas on the Tibetan Plateau.

Morphological changes in the midface of Beagle dogs treated by trans-sutural distraction / Cambios morfológicos en la cara media de perros Beagle tratados por distracción trans-sutural

Trans-sutural distraction is a biological process that induces the formation of new bone and changes the position of bone by pulling on growing suture under the action of external forces. Currently, therapy to midfacial hypoplasia treated by trans-sutural distraction has been applied. In this study, Beagle dogs were selected as experimental animals, and a traction device designed by ourselves was applied to Beagle dogs to simulate the treatment process of trans-sutural distraction in human face, so as to provide a basis for the subsequent research on the related mechanism of trans-sutural distraction. The objective is that the animal model can provide the basis for the follow-up study of transsutural distraction. 45 month beagle dogs were randomly divided into two groups 3 in experiment group and 3 in control group. Implant nails were implanted as the bone marker in the bilateral zygomatic temporal suture, zygomandibular maxillary suture and palatine transverse suture in experimental group. The traction of the maxilla was carried out by the external cranial traction frame with canine fossa as bearing point, 800g force each side, elastic traction for 15 days. The control group only implanted the implant nail as the bone marker on both sides of the bone suture. The distance between two implant nails was measured by vernier calipers and X-ray examination, compared with preoperative and postoperative changes. X-ray and cephalometric measurements were used to measure change in the cranial basal angle. HE staining was used to observe the width of the bone seams, the morphology and structure of the cells and the tissue of the new bone under the phase contrast microscope. Then descriptive statistical analysis and t-test between two independent samples are carried out for the measurement data. The experimental group had a good retention of the beagle traction frame. In the experimental group, the maxillaries of dogs were protrudent in the process of traction gradually and the occlusal relationship changed to type II malocclusion. When the traction is 15 days, the coverage distance is about 8~9 mm. Before and after the traction, the distance between landmark points indicated that the spacing between the transverse palatine suture was the largest (experimental group: 5.52±0.19 mm control group 1.31±0.06 mm P<0.05), and zygomaticotemporal suture was the second (experimental group: 3.12±0.15 mm, control group 0.73±0.04 mm, P<0.05), and zygomaticomaxillary suture was less (experimental group: 2.60±0.34 mm, control group 0.53±0.05 mm, P<0.05). The cranial basal angle was no change before and after operation (controlgroup: 32.3±1.3°, experimental group: 33.2±1.1° P>0.05. Histology showed that the collagenous fibers in the suture of the control group were denser and the osteoblasts were visible on the edge of the suture, showing osteogenic activity. The experimental group significantly widened suture (experimental group: 1209.388±42.714 µm, control group 248.276±22.864 µm, P<0.05), the number of fibroblasts increased significantly with loose collagen fiber. The direction of cell and fiber arrangement were parallel to the traction force. There were many small blood vessels and marrow cavities, and the bone trabecula around the bone suture was thin (experimental group: 23.684±3.774 mm, control group: 86.810±9.219 mm, P < 0.05), showing active osteogenic activity. The growing beagle dog can be used to establish a suture traction animal model for experimental study. In the experiment, Kirschner wire was used to penetrate the bottom plane of the piriform hole of the maxilla (about the position of the canine fossa at the back) and the traction direction was basically the same as the growth direction, and the maxilla was basically parallel and moved forward.

La distracción trans-sutural es un proceso biológico que induce la formación de hueso nuevo y cambia la posición del éste al tirar de la sutura en crecimiento bajo la acción de fuerzas externas. Actualmente, se ha aplicado la terapia para la hipoplasia de la cara media tratada por distracción trans-sutural. En este estudio, fueron seleccionados perros Beagle como animales experimentales, y un dispositivo de tracción fue instalado a los perros para simular el proceso de tratamiento de la distracción trans-sutural en el rostro humano. El objetivo fue proporcionar una base para la investigación posterior sobre mecanismos relacionados con la distracción trans-sutural. El modelo animal puede proporcionar la base para este tipo de estudio de seguimiento de la distracción trans-sutural. Perros Beagle de 45 meses de edad se dividieron aleatoriamente en dos grupos: 3 en el grupo experimental y 3 en el grupo control. Los clavos de implante se usaron como marcadores óseos en la sutura temporal cigomática bilateral, la sutura maxilar cigomandibular y en la sutura transversal palatina en el grupo experimental. La tracción del maxilar se realizó mediante el marco de tracción craneal externo con fosa canina como punto de apoyo, 800 g de fuerza a cada lado, tracción elástica durante 15 días. En el grupo control solo se implantó el clavo del implante como marcador óseo en ambos lados de la sutura. La distancia entre dos clavos de implante se midió mediante calibradores de vernier y examen de rayos X, en comparación con los cambios preoperatorios y postoperatorios. Se utilizaron mediciones cefalométricas y de rayos X para medir el cambio en el ángulo basal craneal. La tinción con HE se usó para observar el ancho de las suturas óseas, la morfología y la estructura de las células y el tejido del hueso nuevo bajo el microscopio de contraste de fase. Luego se realizó un análisis estadístico descriptivo y una prueba t entre dos muestras independientes para los datos de medición. El grupo experimental tuvo una buena retención del cuadro de tracción del Beagle. En el grupo experimental, los maxilares de los perros sobresalieron gradualmente en el proceso de tracción y la relación oclusal cambió a maloclusión tipo II. Cuando la tracción era de 15 días, la distancia de cobertura fue de aproximadamente 8 ~ 9 mm. Antes y después de la tracción, la distancia entre los puntos de referencia indicaba que el espacio entre la sutura palatina transversal era más grande (grupo experimental: 5,52 ± 0,19 mm, grupo de control 1,31 ± 0,06 mm, P <0,05), y la sutura cigomáticotemporal fue la segunda. (Grupo experimental: 3,12 ± 0,15 mm, grupo control 0,73 ± 0,04 mm, P <0,05), y la sutura cigomaticomaxilar fue menor (grupo experimental, 2,60 ± 0,34 mm, grupo control 0,53 ± 0,05 mm, P <0,05). El ángulo basal craneal no cambió antes ni después de la operación (grupo control 32,3 ± 1,3, grupo experimental, 33,2 ± 1,1 ° , P> 0,05). La histología mostró que las fibras colágenas en la sutura del grupo control eran más densas y los osteoblastos se observaron en el margen de la sutura, mostrando actividad osteogénica. En el grupo experimental se amplió significativamente la sutura (1209,388 ± 42,714 µm, grupo control 248,276 ± 22,864 µm, P <0,05), el número de fibroblastos aumentó significativamente con fibras colágenas dispersas. La dirección de la disposición de la celda y las fibras era paralela a la fuerza de tracción. Se observó gran cantidad de vasos sanguíneos pequeños, cavidades medulares, y trabéculas óseas alrededor de la sutura ósea (grupo experimental: 23,684 ± 3,774 mm, grupo control: 86,810 ± 9,219 mm, P <0,05), que mostró actividad osteogénica activa. El perro Beagle en crecimiento se puede utilizar para estudios experimentales y así establecer un modelo animal de tracción de sutura. En el proceso, se usó alambre de Kirschner para penetrar en el plano inferior del foramen piriforme del maxilar (aproximadamente en la posición de la fosa canina en la parte posterior) y la dirección de tracción fue básicamente la misma que en el crecimiento.

Medial Open-wedge Osteotomy with Double-plate Fixation for Varus Malunion of the Distal Femur.

OBJECTIVE: To present our clinical experience of treating varus malunion of the distal femur through a medial open-wedge osteotomy with double-plate fixation. METHODS: A prospective cohort study was performed. From January 2005 to February 2015, 15 consecutive patients with varus malunion following distal femur fractures were surgically treated at a single level I trauma center. The coronal and sagittal deformity were corrected by a medial open-wedge osteotomy of the distal femur. A medial buttress plate was used to maintain the realignment. A lateral locking plate was additionally used as a protection plate. The mean age of patients at the time of the surgery was 35.5 years (range, 22-58 years). The radiographical evaluation included the mechanical femorotibial angle, the mechanical lateral distal femoral angle, the anatomic posterior distal femoral angle, and the leg length discrepancy. Clinical outcome evaluation consisted of the range of motion (ROM) and Hospital for Special Surgery (HSS) score. RESULTS: Mean follow-up was 7.4 years (range, 4-11.5 years). Varus and flexion malalignment and limb discrepancy were adequately corrected in all patients. The mechanical femorotibial angle, the mechanical lateral distal femoral angle, and the anatomic posterior distal femoral angle were restored from 17.5° (range, 13°-25°) to 2.3° (range, - 2°-7°), 102.3° (range, 95°-112°) to 85.2° (range, 81°-92°), and 77.1° (range, 65°-87°) to 82.7° (range, 76°-88°), respectively. The leg length discrepancy was diminished from 3.4 cm (range, 2.4-4.5 cm) to 0.8 cm (range, 0-1.7 cm). The average bone healing time was 4.1 months (range, 2.5-6 months). The average ROM of the affected knees at 24-month follow-up was 3.4°-112.55°. The score of HSS at 4-years follow-up was 76.1 (range, 64-88). No internal fixation failure or secondary operation was noted until the last follow-up. CONCLUSION: Medial open-wedge osteotomy can adequately correct the posttraumatic varus malunion of the distal femur. With fixation of the double plate, non-displaced bone healing and good functional outcome are expected.

Nicotine modulates the facial stimulation-evoked responses in cerebellar granule cell layer in vivo in mice.

Nicotinic acetylcholine receptors are cationic channels that mediate fast excitatory transmission in the central nervous system. Several nicotinic acetylcholine receptor subunits have been detected within cerebellar granule cell layer (GCL), and activation of these receptors may have a significant influence on neuronal synaptic transmission of the cerebellum. The aim of present study was to better understand the roles of nicotinic acetylcholine receptors during the sensory stimulation-evoked synaptic transmission in the cerebellar GCL. Our results showed that cerebellar surface perfusion of nicotine significantly facilitated the cerebellar GCL field potential responses evoked by air-puff stimulation of ipsilateral whisker pad, which exhibited increases in amplitude and area under the curve (AUC) of both stimulus onset responses (N1) and stimulus offset responses (N2). The nicotine-induced increase in AUC of facial stimulation-evoked N1 was dose-dependent with a 50% effective concentration (EC50) of 32.6 µM. Application of either a selective α4ß2 nicotinic acetylcholine receptors antagonist, DHßE (1 µM) or a selective α7 nicotinic acetylcholine receptors antagonist, MLA (1 µM) alone attenuated, but not completely abolished the nicotine-induced increases in the amplitude and AUC of the facial stimulation-evoked N1. However, simultaneous blockade of α7 and α4ß2 nicotinic acetylcholine receptor subunits abolished the nicotine-induced increase in the amplitude of N1. These results indicate that nicotine activates α7 and α4ß2 nicotinic acetylcholine receptor subunits, resulting in an enhancement of facial stimulation-evoked responses in mouse cerebellar GCL. Our results suggest that nicotine modulates the sensory information processing in the cerebellar GCL through α7 and α4ß2 subunits nicotinic acetylcholine receptors.

Morphological observation of bone marrow mesenchymal stem cells under matrigel three dimensional culture conditions / Observación morfológica de células madre mesenquimales de médula ósea en condiciones de cultivo tridimensional con matrigel

SUMMARY: Matrigel is a basement membrane matrix extracted from the EHS mouse tumor containing extracellular matrix protein, its main components are laminin, type IV collagen, nestin, heparin sulfate, growth factor and matrix metalloproteinase.At room temperature, Matrigel polymerized to form a three dimensional matrix with biological activity. It can simulate the structure, composition, physical properties and functions of the cell basement membrane in vivo, which is beneficial to the culture and differentiation of the cells in vitro, and can be used for the study of cell morphology, biochemical function, migration, infection and gene expression. In this study, Matrigel three-dimensional culture model of bone marrow mesenchymal stem cells(BMSCs) was established, and its morphology, proliferation and survival were observed. BMSCs were isolated and cultured with whole bone marrow adherence method. The Second generation BMSCs with good growth condition were selected and mixed with Matrigel to form cell gel complexes. The morphology and proliferation of mesenchymal stem cells were observed by phase contrast microscope and HE staining,Live/Dead staining was used to evaluate the cell activity.Phase contrast microscopy showed that BMSCs were reticulated in Matrigel and proliferated well, After 7 days, the matrix gel gradually became soft and collapsed, a few cell reticular crosslinking growth was seen at 14 days; HE staining showed that the cytoplasm of the cells was larger on the fourth day and the cells were elongated and cross-linked on the seventh day; Live/dead staining showed that most cells showed green fluorescence with the prolongation of culture time, on the first, 4 and 7 days, the activity of bone marrow mesenchymal stem cells in Matrigel gradually increased, and the percentages were 92.57 %, 95.54 % and 97.37 %, respectively. Matrigel three-dimensional culture system can maintain the morphology, function and proliferation ability of bone marrow mesenchymal stem cells.

RESUMEN: Matrigel es una matriz de membrana basal extraída del tumor de ratón EHS que contiene proteína de matriz extracelular. Los componentes principales son laminina, el colágeno tipo IV, nestina, sulfato de heparina, factor de crecimiento y metaloproteinasa de matriz. A temperatura ambiente, Matrigel se polimerizó para formar una matriz tridimensional. Es posible simular la estructura, la composición, las propiedades físicas y las funciones de la membrana basal celular in vivo, lo que es beneficioso para el cultivo y la diferenciación de las células in vitro, y se puede utilizar para el estudio de la morfología celular, la función bioquímica, la migración, infección y expresión génica. En este estudio, se estableció el modelo de cultivo tridimensional Matrigel de células madre mesenquimales de médula ósea (BMSC), y se observó su morfología, proliferación y supervivencia. Las BMSC fueron aisladas y cultivadas con el método de adherencia de la médula ósea completa. Se seleccionaron las BMSC de segunda generación con buenas condiciones de crecimiento y se mezclaron con Matrigel para formar complejos de gel de células. La morfología y la proliferación de las células madre mesenquimales se observaron con microscopio de contraste de fase y se tiñó con Hematoxilina-Eosina (HE); para evaluar la actividad celular se usó la tinción Live/Dead. La microscopía de contraste mostró que las BMSC se reticularon en Matrigel y proliferaron bien. Después de 7 días, se observó que el gel de matriz gradualmente se volvió blando y colapsó, y se visualizó un cruce transversal de algunas células reticulares a los 14 días. La tinción mostró que la mayoría de las células mostraron una fluorescencia verde con la prolongación del tiempo de cultivo; en los primeros 4 y 7 días, la actividad de las células madre mesenquimales de la médula ósea en Matrigel aumentó gradualmente y los porcentajes fueron de 92,57 %, 95,54 % y 97,37 %, respectivamente. El sistema de cultivo tridimensional de Matrigel puede mantener la morfología, la función y la capacidad de proliferación de las células madre mesenquimales de la médula ósea.

Tibial plateau fractures in elderly people: an institutional retrospective study.

BACKGROUND: Tibial plateau fractures are the most common intra-articular fractures, which require careful evaluation and preoperative planning. The treatment of tibial plateau fractures in elderly patients is challenging, and the comprehension of epidemiology and morphology can be helpful. This study described the characteristics of geriatric tibial plateau fractures. METHODS: A total of 327 (23.24%) patients aged ≥60 years were reviewed in our level one trauma center over a 4-year period (from January 2013 to November 2016). The following parameters were collected and evaluated: (1) demographic data, (2) injury mechanisms and (3) fracture classifications. RESULTS: Females accounted for 60.86% in all included elderly patients. Electric-bike accidents were the cause of 32.42% of all these injuries, and 39.62% of these led to high-energy injuries. The most common type of fracture was Schatzker II (54.74%). According to the three-column classification, single lateral column fracture (28.75%) and four-quadrant fracture (involving lateral, medial, posterolateral and posteromedial fractures) (23.24%) were the two most frequent patterns. In all cases, 67.58% involved the posterior column, and the prevalence of posterolateral and posteromedial fractures were 62.69% and 37.92% respectively. Isolated posterior column fractures accounted for 12.54% of patients in total, which mostly consisted of posterolateral fracture in older females (85.37%). CONCLUSIONS: The majority of elderly patients with tibial plateau fractures are females, and Electric-bike accidents are an important cause of injury. Geriatric tibial plateau fractures have unique distribution in classification.

Expression Profiling Identifies Circular RNA Signature in Hepatoblastoma.

BACKGROUND/AIMS: Hepatoblastoma is the most common malignant pediatric liver cancer. circular RNAs (circRNAs) play important roles in fine-tuning gene expression and are often deregulated in cancers. However, the expression profile and clinical significance of circRNAs in hepatoblastoma is still unknown. METHODS: Circular RNA microarray was conducted to identify hepatoblastoma-related circRNAs. GO analysis, pathway analysis, and miRNA response elements analysis was conducted to predict the potential roles of differentially expressed circRNAs in hepatoblastoma. MTT assays, Ki67 staining, and Transwell assays were conducted to clarify the role of circRNA in hepatoblastoma in vitro. Bioinformatics analysis and in vitro experiments were conducted to clarify the mechanism of circRNA-mediated gene regulation in hepatoblastoma cell. RESULTS: 869 differentially expressed circRNAs were identified between hepatoblastoma and adjacent normal liver samples, including 421 up-regulated circRNAs and 448 down-regulated circRNAs. The significant enriched GO term of hepatoblastoma-related circRNAs in biological process, cellular component, and molecular function were "chromosome organization", "cytoplasm", and "organic cyclic compound binding". Tight junction signaling pathway was ranked the Top 1 potentially affected by circRNA-mediated regulatory network. circ_0015756 was significantly up-regulated in human hepatoblastoma specimens and metastatic hepatoblastoma cell lines. circ_0015756 silencing decreased hepatoblastoma cell viability, proliferation, and invasion in vitro. circ_0015756 acted as miR-1250-3p sponge to regulate hepatoblastoma cell function. CONCLUSIONS: circRNAs are involved in the pathogenesis of hepatoblastoma. circ_0015756 is a promising target for the prognosis, diagnosis, and treatment of hepatoblastoma.

Long non-coding RNA-CRNDE: a novel regulator of tumor growth and angiogenesis in hepatoblastoma.

Long non-coding RNAs (lncRNAs) are involved in many biological processes, such as angiogenesis, invasion, cell proliferation, and apoptosis. They have emerged as key players in the pathology of several tumors, including hepatoblastoma. In this study, we elucidate the biological and clinical significance of CRNDE up-regulation in hepatoblastoma. CRNDE is significantly up-regulated in human hepatoblastoma specimens and metastatic hepatoblastoma cell lines. CRNDE knockdown reduces tumor growth and tumor angiogenesis in vivo, and decreases hepatoblastoma cell viability, proliferation, and angiogenic effect in vitro. Mechanistic studies show that CRNDE knockdown plays its anti-proliferation and anti-angiogenesis role via regulating mammalian target of rapamycin (mTOR) signaling. Taken together, this study reveals a crucial role of CRNDE in the pathology of hepatoblastoma. CRNDE may serve as a promising diagnostic marker and therapeutic target for hepatoblastoma.

RNA-binding protein RBM3 prevents NO-induced apoptosis in human neuroblastoma cells by modulating p38 signaling and miR-143.

Nitric oxide (NO)-induced apoptosis in neurons is an important cause of neurodegenerative disease in humans. The cold-inducible protein RBM3 mediates the protective effects of cooling on apoptosis induced by various insults. However, whether RBM3 protects neural cells from NO-induced apoptosis is unclear. This study aimed to investigate the neuroprotective effect of RBM3 on NO-induced apoptosis in human SH-SY5Y neuroblastoma cells. Firstly, we demonstrated that mild hypothermia (32 °C) induces RBM3 expression and confers a potent neuroprotective effect on NO-induced apoptosis, which was substantially diminished when RBM3 was silenced by siRNA. Moreover, overexpression of RBM3 exhibited a strong protective effect against NO-induced apoptosis. Signaling pathway screening demonstrated that only p38 inhibition by RBM3 provided neuroprotective effect, although RBM3 overexpression could affect the activation of p38, JNK, ERK, and AKT signaling in response to NO stimuli. Notably, RBM3 overexpression also blocked the activation of p38 signaling induced by transforming growth factor-ß1. Furthermore, both RBM3 overexpression and mild hypothermia abolished the induction of miR-143 by NO, which was shown to mediate the cytotoxicity of NO in a p38-dependent way. These findings suggest that RBM3 protects neuroblastoma cells from NO-induced apoptosis by suppressing p38 signaling, which mediates apoptosis through miR-143 induction.

Nicotine enhances GABAergic inhibition of oxytocin mRNA-expressing neuron in the hypothalamic paraventricular nucleus in vitro in rats.

We recently found that extracellular administration of nicotine indirectly excited hypothalamic paraventricular nucleus (PVN) corticotropin-releasing hormone (CRH) mRNA-expressing neurons. In this study, we studied the effect of nicotine on PVN oxytocin (OT) mRNA-expressing neuron in vitro in rats, by whole-cell patch-clamp recording technique, immunohistochemistry methods and single-cell reverse-transcription multiplex polymerase chain reaction (SC-RT-mPCR) methods Our results showed that 79.3% (73/92) of the 92 PVN putative magnocellular neurons co-expressed GAPDH mRNA and OT mRNA. Under current-clamp recording conditions, local micro application of nicotine (1-300µM) induced a decrease in spontaneous firing rate accompanied with a hyperpolarization of membrane potential in 76.7% (56/73) of PVN OT mRNA-expressing magnocellular neurons. The nicotine induced inhibition in spontaneous activity of PVN OT mRNA-expressing magnocellular neurons was dose-dependent. The half-inhibitory concentration (IC50) is 2.9µM. The nicotine induced hyperpolarization of PVN OT mRNA-expressing magnocellular neurons was sensitive to GABAA receptor antagonist, SR95531 (10µM) and tetrodotoxin (TTX, 1µM). In addition, local micro application of nicotine induced a significant increase in frequency of spontaneous inhibitory postsynaptic potentials (sIPSPs), but without changes in the sEPSPs amplitude of the OT-mRNA expressing neurons. Biocytin staining confirmed that the nicotine-sensitive OT-mRNA expressing neurons were the PVN magnocellular neurons. These results demonstrated that nicotine enhances the GABAergic inhibition, resulting in a decrease in spontaneous firing rate of the PVN OT-mRNA expressing neurons. These findings suggested that nicotine modulated PVN OT secretion via enhancement of both presynaptic action potential drive and quantal GABA release.

Thrombospondin-4 Promotes Neuronal Differentiation of NG2 Cells via the ERK/MAPK Pathway.

NG2-expressing neural progenitors can produce neurons in the central nervous system, providing a potential cell resource of therapy for neurological disorders. However, the mechanism underlying neuronal differentiation of NG2 cells remains largely unknown. In this report, we found that a thrombospondin (TSP) family member, TSP4, is involved in the neuronal differentiation of NG2 cells. When TSP4 was overexpressed, NG2 cells underwent spontaneous neuronal differentiation, as demonstrated by the induction of various neuronal differentiation markers such as NeuN, Tuj1, and NF200, at the messenger RNA and protein levels. In contrast, TSP4 silencing had an opposite effect on the expression of neuronal differentiation markers in NG2 cells. Next, the signaling pathway responsible for TSP4-mediated NG2 cell differentiation was investigated. We found that ERK but not p38 and AKT signaling was affected by TSP4 overexpression. Furthermore, when ERK signaling was blocked by the inhibitor U0126, the neuronal marker expression of NG2 cells was substantially increased. Together, these findings suggested that TSP4 promoted neuronal differentiation of NG2 cells by inhibiting ERK/MAPK signaling, revealing a novel role of TSP4 in cell fate specification of NG2 cells.

Nicotine excites corticotropin-releasing hormone mRNA-expressing neuron in the hypothalamic paraventricular nucleus in vitro in rats.

Nicotine is known to modulate the activity of the hypothalamic-pituitary-adrenal axis by stimulating corticotropin-releasing hormone (CRH) release from the hypothalamic paraventricular nucleus (PVN). However, the mechanism by which nicotine affects the hypothalamic-pituitary-adrenal axis by modulating PVN CRH neuronal activity is currently unclear. Here, we examined the effects of nicotine on PVN CRH-mRNA-expressing neurons in vitro in rats by whole-cell patch-clamp recordings, biocytin staining, and single-cell reverse transcription-multiplex PCR techniques. Of the 146 PVN putative parvocellular neurons, 17.1% (25/146) coexpressed GAPDH mRNA and CRH mRNA. Under current-clamp recording conditions, application of nicotine (1 µM) induced excitation in 92% (23/25) PVN CRH-mRNA-expressing neurons, which showed a significant increase in the spike firing rate accompanied by a depolarization of the membrane potential. Nicotine induced an increase in the spike firing rate of PVN CRH-mRNA-expressing neurons in a concentration-dependent manner. The half-effective concentration (EC50) of nicotine for increasing the spike firing rate of PVN CRH-mRNA-expressing neurons was 1.6 µM. Extracellular application of ionotropic glutamate receptor antagonist kynurenic acid (1 mM) abolished the nicotine-induced excitation of PVN CRH-mRNA-expressing neurons. Moreover, application of nicotine induced a significant increase in the spontaneous excitatory postsynaptic currents frequency, but without significantly altering the spontaneous excitatory postsynaptic currents amplitude of the CRH-mRNA-expressing neurons. Biocytin staining confirmed that the nicotine-sensitive CRH-mRNA-expressing neurons were located in the PVN parvocellular division. These results indicated that extracellular administration of nicotine indirectly excited PVN CRH-mRNA-expressing neurons, suggesting that nicotine modulated PVN CRH secretion by enhancement of both the presynaptic action potential drive and quantal glutamate release.