A Minimally Invasive Annulus Fibrosus Needle Puncture Model of Intervertebral Disc Degeneration in Rats.

BACKGROUND: The needle puncture model in rats has been accepted as an ordinary model to induce intervertebral disc degeneration (IVDD). However, the model primarily penetrated the whole intervertebral disc, resulting in injury to the nucleus pulposus (NP) and annulus fibrosus (AF). The intention of this research was to explore a minimally invasive approach through needle puncture of the AF percutaneously in rats. METHODS: Twenty SD rats underwent puncture at Co8/9 via a 20 G percutaneous needle. The needle was slowly advanced perpendicular to the tail skin to penetrate the whole AF without damaging the NP limited by a hand-made sheath. The X-rays and magnetic resonance imaging T2 relaxation was evaluated at 1, 2, and 3 weeks to assess the disc height index and signal changes. Histological and immunohistochemical staining of the IVD were obtained under a light microscope. RESULTS: X-rays showed that the disc height had progressively narrowed to 49% of baseline 3 weeks after injury. magnetic resonance imaging evaluation demonstrated that the mean T2-weighted signal intensity at 3 weeks was 43% of that in the uninjured control group at the Co8/9 level. Histological staining demonstrated disorganized lamellae in the AF and decreased proteoglycan content and cellularity within the NP in the injured discs. CONCLUSIONS: The present research demonstrates a reliable and convenient approach to induce an AF tear in rats through percutaneous needle puncture. This model reduces harm to the experimental animals significantly while imitating the progressive degeneration process. More importantly, the model confirmed that AF damage alone could lead to IVDD and provided a research method for AF degeneration in IVDD.

CB2R Attenuates Intervertebral Disc Degeneration by Delaying Nucleus Pulposus Cell Senescence through AMPK/GSK3ß Pathway.

Nucleus pulposus (NP) cell (NPC) senescence is one of the main causes of intervertebral disc degeneration (IVDD). However, the underlying mechanism of NPC senescence is still unclear. The cannabinoid type 2 receptor (CB2R) is a member of the cannabinoid system and plays an important role in antioxidative stress, anti-inflammatory and antisenescence activities. In this study, we used a hydrogen peroxide (H2O2)-induced NPC senescence model and a rat acupuncture IVDD model to explore the role of CB2R in IVDD in vitro and in vivo. First, we confirmed that the expression of p16INK4a in the NP tissues of IVDD patients and rat acupuncture IVDD models obviously increased accompanied by a decrease in CB2R expression. Subsequently, we found that activation of CB2R significantly reduced the number of SA-ß-gal positive cells and suppressed the expression of p16INK4a and senescence-related secretory phenotypes [SASP, including matrix metalloproteinase 9 and 13 (MMP9, MMP13) and high mobility group protein b1 (HMGB1)]. In addition, activation of CB2R promoted the expression of collagen type II (Col-2) and SRY-Box transcription factor 9 (SOX9), inhibit the expression of collagen type X (Col-X), and restore the balance of extracellular matrix (ECM) metabolism. In addition, the AMPK/GSK3ß pathway was shown to play an important role in CB2R regulation of NPC senescence. Inhibition of AMPK expression reversed the effect of JWH015 (a CB2R agonist). Finally, we further demonstrated that in the rat IVDD model, the AMPK/GSK3ß pathway was involved in the regulation of CB2R on NPC senescence. In conclusion, our experimental results prove that CB2R plays an important role in NPC senescence. Activation of CB2R can delay NPC senescence, restore the balance of ECM metabolism, and attenuate IVDD.

CB2-mediated attenuation of nucleus pulposus degeneration via the amelioration of inflammation and oxidative stress in vivo and in vitro.

BACKGROUND: Nucleus pulposus cell (NPC) degeneration is widely accepted as one of the major causes of intervertebral disc (IVD) degeneration (IVDD). The pathogenesis of IVDD is complex and consists of inflammation, oxidative stress, and the loss of extracellular matrix (ECM). Cannabinoid type 2 receptor (CB2) has been shown to be involved in the pathological mechanism of a variety of diseases due to its anti-inflammatory effects and antioxidative stress capacity. METHOD: In Vitro, H2O2 was used to induce degeneration of nucleus pulposus cells, mRNA and protein expression level was determined by RT-PCR and Western Blot, and Immunocytochemical staining were used to detect expression of collagen II, aggrecan, MMP3/13, superoxide dismutase 2 (SOD2) and inducible nitric oxide synthase (iNOS). In vivo, the potential therapeutic effect of CB2 was detected in the rat acupuncture model. RESULT: In vitro, we found that the CB2 agonist (JWH133) treatment reduced the oxidative stress level in NPCs induced by hydrogen peroxide (H2O2) treatment. Furthermore, the expression of inflammatory cytokines was also decreased by JWH133 treatment. We found that collagen II and aggrecan expression was preserved, whereas matrix metalloproteinase levels were reduced. In vivo, we established a rat model by needle puncture. Imaging assessment revealed that the disc height index (DHI) and morphology of IVD were significantly improved, and the disc degeneration process was delayed by treatment of JWH133. Furthermore, immunohistochemical (IHC) staining revealed that JWH133 could inhibit the degradation of collagen II and decrease the expression of MMP3. CONCLUSIONS: The experiment indicates the oxidative stress and inflammatory response of rat NPCs induced by H2O2 could be inhibited by activating CB2. This study reveals that CB2 activation can effectively delay the development of IVDD, providing an effective therapeutic target for IVDD.

Treatment of intestinal graft-versus-host disease with unrelated donor fecal microbiota transplantation capsules: A case report.

INTRODUCTION: Fecal microbiota transplantation (FMT), administering fecal suspensions via a nasoduodenal tube, has achieved a promising effect in the treatment of intestinal graft-versus-host disease (GvHD) in some pilot studies. In this study, oral FMT capsules from unrelated donor were used for the first time in the treatment of intestinal GvHD. Patient concerns: A 31-year-old male who was diagnosed as "myelodysplastic syndromes with excess blasts II" (intermediate risk 2 of international prognostic scoring system) received human leukocyte antigen -matched sibling donor allogeneic hematopoietic stem cell transplantation. The patient developed diarrhea, vomiting, and bloody stool on 28 days after transplantation. DIAGNOSIS: Intestinal acute GvHD was diagnosed clinically with histological confirmation by colonoscopy and pathological biopsy. INTERVENTIONS: This patient was treated with first cycle of oral FMT capsules after failure to initial treatment of methylprednisolone (2 mg/kg/d) combined with recombinant human tumor necrosis factor-α receptorII: IgG Fc fusion protein (25 mg, biw). The symptoms of intestinal GvHD were relieved but recurred 11 days later. Second cycle of oral FMT capsules was carried out. OUTCOMES: After 2 cycles of fecal bacteria transplantation, intestinal GvHD was gradually controlled and did not recur again during the 2-month follow-up. The diversity and structure of the intestinal flora after FMT was closer to that of healthy donors than that before. CONCLUSION: Our case showed oral FMT capsules could be used as a treatment option for corticosteroid refractory intestinal GvHD. Further studies are warranted to assess the clinical efficacy and safety of oral FMT capsules in the treatment of intestinal GvHD. RATIONALE: Fecal microbiota transplantation (FMT), administering fecal suspensions via a nasoduodenal tube, has achieved a promising effect in the treatment of intestinal graft-versus-host disease (GvHD) in some pilot studies. In this study, oral FMT capsules from unrelated donor were used for the first time in the treatment of intestinal GvHD. PATIENT CONCERNS: A 31-year-old male who was diagnosed as "myelodysplastic syndromes with excess blasts II" (intermediate risk 2 of international prognostic scoring system) received human leukocyte antigen -matched sibling donor allogeneic hematopoietic stem cell transplantation. The patient developed diarrhea, vomiting, and bloody stool on 28 days after transplantation. DIAGNOSES: Intestinal acute GvHD was diagnosed clinically with histological confirmation by colonoscopy and pathological biopsy. INTERVENTIONS: This patient was treated with first cycle of oral FMT capsules after failure to initial treatment of methylprednisolone (2 mg/kg/d) combined with recombinant human tumor necrosis factor-a receptorII: IgG Fc fusion protein (25 mg, biw). The symptoms of intestinal GvHD were relieved but recurred 11 days later. Second cycle of oral FMT capsules was carried out. OUTCOMES: After 2 cycles of fecal bacteria transplantation, intestinal GvHD was gradually controlled and did not recur again during the 2-month follow-up. The diversity and structure of the intestinal flora after FMT was closer to that of healthy donors than that before. CONCLUSION: Our case showed oral FMT capsules could be used as a treatment option for corticosteroid refractory intestinal GvHD. Further studies are warranted to assess the clinical efficacy and safety of oral FMT capsules in the treatment of intestinal GvHD. LESSONS: There is still a possibility of recurrence after the treatment of GvHD with capsule fecal microbiota transplantation. How to optimize the dosage and treatment course of fecal microbiota capsule administration needs further exploration.

Gut microbiome and osteoporosis: a review.

Osteoporosis (OP) is a chronic metabolic bone disease characterized by the decrease of bone tissue per unit volume under the combined action of genetic and environmental factors, which leads to the decrease of bone strength, makes the bone brittle, and raises the possibility of bone fracture. However, the exact mechanism that determines the progression of OP remains to be underlined. There are hundreds of trillions of symbiotic bacteria living in the human gut, which have a mutually beneficial symbiotic relationship with the human body that helps to maintain human health. With the development of modern high-throughput sequencing (HTS) platforms, there has been growing evidence that the gut microbiome may play an important role in the programming of bone metabolism. In the present review, we discuss the potential mechanisms of the gut microbiome in the development of OP, such as alterations of bone metabolism, bone mineral absorption, and immune regulation. The potential of gut microbiome-targeted strategies in the prevention and treatment of OP was also evaluated. Cite this article: Bone Joint Res 2020;9(8):524-530.

Efficient degradation of chlorobenzene in a non-thermal plasma catalytic reactor supported on CeO2/HZSM-5 catalysts.

Chlorobenzene removal was investigated in a non-thermal plasma reactor using CeO2/HZSM-5 catalysts. The performance of catalysts was evaluated in terms of removal and energy efficiency. The decomposition products of chlorobenzene were analyzed. The results show that CeO2/HZSM-5 exhibited a good catalytic activity, which resulted in enhancements of chlorobenzene removal, energy efficiency, and the formation of lower amounts of by-products. With regards to CO2 selectivity, the presence of catalysts favors the oxidation of by-products, leading to a higher CO2 selectivity. With respect to ozone, which is considered as an unavoidable by-product in air plasma reactors, a noticeable decrease in its concentration was observed in the presence of catalysts. Furthermore, the stability of the catalyst was investigated by analyzing the evolution of conversion in time. The experiment results indicated that CeO2/HZSM-5 catalysts have excellent stability: chlorobenzene conversion only decreased from 78% to 60% after 75hr, which means that the CeO2/HZSM-5 suffered a slight deactivation. Some organic compounds and chlorinated intermediates were adsorbed or deposited on the catalysts surface as shown by the results of Fourier Transform Infrared (FT-IR) spectroscopy, scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS) analyses of the catalyst before and after the reaction, revealing the cause of catalyst deactivation.

Conversion characteristics and production evaluation of styrene/o-xylene mixtures removed by DBD pretreatment.

The combination of chemical oxidation methods with biotechnology to removal recalcitrant VOCs is a promising technology. In this paper, the aim was to identify the role of key process parameters and biodegradability of the degradation products using a dielectric barrier discharge (DBD) reactor, which provided the fundamental data to evaluate the possibilities of the combined system. Effects of various technologic parameters like initial concentration of mixtures, residence time and relative humidity on the decomposition and the degradation products were examined and discussed. It was found that the removal efficiency of mixed VOCs decreased with increasing initial concentration. The removal efficiency reached the maximum value as relative humidity was approximately 40%-60%. Increasing the residence time resulted in increasing the removal efficiency and the order of destruction efficiency of VOCs followed the order styrene > o-xylene. Compared with the single compounds, the removal efficiency of styrene and o-xylene in the mixtures of VOCs decreased significantly and o-xylene decreased more rapidly. The degradation products were analyzed by gas chromatography and gas chromatography-mass spectrometry, and the main compounds detected were O3, COx and benzene ring derivatives. The biodegradability of mixed VOCs was improved and the products had positive effect on biomass during plasma application, and furthermore typical results indicated that the biodegradability and biotoxicity of gaseous pollutant were quite depending on the specific input energy (SIE).

[Treatment of organic waste gas by adsorption rotor].

The adsorption rotor is applicable to treating organic waste gases with low concentration and high air volume. The performance of adsorption rotor for purifying organic waste gases was investigated in this paper. Toluene was selected as the simulative gaseous pollutant and the adsorption rotor was packed with honeycomb modified 13X molecular sieves (M-13X). Experimental results of the fixed adsorption and the rotor adsorption were analyzed and compared. The results indicated that some information on the fixed adsorption was useful for the rotor adsorption. Integrating the characteristics of the adsorbents, waste gases and the structures of the rotor adsorption, the formulas on optimal rotor speed and cycle removal efficiency of the adsorption rotor were deduced, based on the mass and heat balances of the adsorbing process. The numerical results were in good agreement with the experimental data, which meant that the formulas on optimal rotor speed and cycle removal efficiency could be effectively applied in design and operation of the adsorption rotor.