Conditional protein splicing triggered by SUMO protease.

Conditional protein splicing is a powerful biotechnological tool that can be used to post-translationally control the activity of target proteins. Here we demonstrated a novel conditional protein splicing approach in which the small ubiquitin-like modifier (SUMO) protease induced the splicing of an atypical split intein. The engineered Ter DnaE-3 S11 split intein which has a small C-intein segment with only 6 amino acids was used in this study. A SUMO tag was fused to the N-terminus of the C-intein to inhibit the protein trans-splicing in vitro. The splicing products could be detected in 15 min with the addition of SUMO protease by western blotting and the splicing efficiency was ∼4-fold higher than the control without SUMO protease for overnight reaction. This engineered Ter DnaE-3 S11 split intein-mediated protein trans-splicing had been further shown to be triggered by SUMO protease in different exteins in vitro. Our study provides new insights into the regulation of protein splicing and is a promising tool for the control of protein structure and function in vitro.

Proliferative glomerulonephritis with monoclonal IgG Lambda deposits caused by plasmablastic lymphoma: a case report.

INTRODUCTION: As a very rare form of B-cell lymphoma, plasmablastic lymphoma (PBL) typically occurs in patients with underlying immunosuppression, including human immunodeficiency virus (HIV), organ transplantation, and autoimmune diseases. For HIV-positive patients, PBL normally originates in the gastrointestinal tract, especially from the oral cavity in most cases. It is extremely rare to find abdominal cavity involvement in PBL, and there has been no previously reported instance of proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID) attributed to monoclonal IgG (MIgG) lambda secreted by PBL. CASE PRESENTATION: We report the case of an HIV-negative female with nephrotic syndrome, renal insufficiency, and multiple swollen lymph nodes. Ascitic fluid cytology revealed a high level of plasmablast-like lymphocytes with the restriction of lambda light chains. Besides, the renal biopsy revealed PGNMID, which could presumably be secondary to MIgG-lambda-secreting by PBL. MIgG-lambda-restricted expression was discovered earlier in the kidney tissue than in the blood. CONCLUSION: The diagnostic landscape for PBL is notoriously intricate, necessitating a multifaceted and nuanced approach to mitigate the risks of erroneous identification.

Efficient splicing of the CPE intein derived from directed evolution of the Cryptococcus neoformans PRP8 intein.

Intein-mediated protein splicing has been widely used in protein engineering; however, the splicing efficiency and extein specificity usually limit its further application. Thus, there is a demand for more general inteins that can overcome these limitations. Here, we study the trans-splicing of CPE intein obtained from the directed evolution of Cne PRP8, which shows that its splicing rate is ~29- fold higher than that of the wild-type. When the +1 residue of C-extein is changed to cysteine, CPE also shows high splicing activity. Faster association and higher affinity may contribute to the high splicing rate compared with wild-type intein. These findings have important implications for the future engineering of inteins and provide clues for fundamental studies of protein structure and folding.

Triptolide Alleviates Neuropathic Pain by Inhibiting the Activation of Microglial Toll-Like Receptor 3.

BACKGROUND: Current data indicates the incidence of neuropathic pain after surgical nerve injury is as high as 50%, thus representing a major problem for patients and for the medical system. Triptolide, a traditional Chinese herb, has anti-inflammatory effects on various neurodegenerative and neuroinflammatory diseases. This agent also reduces peripheral nerve injury-induced neuropathic pain, although the mechanism underlying this effect is still unknown. MATERIALS AND METHODS: The effects of triptolide on spinal nerve ligation (SNL) injury-induced neuropathic pain was studied in an animal model using behavioral, morphological and molecular biological methods. RESULTS: Repeated administration of intrathecal triptolide was found to alleviate SNL- or Poly(I:C) (toll-like receptor 3 agonist) injection-induced mechanical allodynia without any motor impairment. The mechanism by which triptolide reduces SNL- and Poly(I:C) injection-induced microglial activation appears to be via the inhibition of OX42 expression, which is a microglial-specific marker. Intrathecal triptolide also suppressed SNL- and Poly(I:C) injection-induced expression of spinal TRIF. TRIF transmits signals from activated TLR3 and is the downstream adaptor of TLR3 in microglia. In addition, intrathecal triptolide inhibited the expression of spinal pro-inflammatory IL-1 ß following SNL or Poly(I:C) injection. CONCLUSIONS: Intrathecal triptolide can suppress the TLR3/TRIF/IL-1 ß pathway in spinal microglia following SNL. This could be the underlying mechanism by which triptolide alleviate neuropathic pain induced by peripheral nerve injury.

The value of microendoscopy in the diagnosis of cervical precancerous lesions and cervical microinvasive carcinoma.

PURPOSE: Cervical cancer is still one of the main causes of death in females. Conventional diagnostic tools such as colposcopy are still unsatisfactory, so accurate diagnostic tools for cervical diseases are needed. Therefore, the purpose of this study was to perform a clinical study to evaluate the value of microendoscopic imaging systems in the diagnosis of cervical precancerous lesions and cervical microinvasive carcinoma (MIC). METHODS: Totally 106 patients ranging in age from 23 to 67 years were recruited. All patients had abnormal thin-layer cytology (TCT) results (≥ low-grade squamous intraepithelial lesions) and high-risk human papillomavirus (HPV) positivity. Each patient was first subjected to ordinary colposcopy, followed by microendoscopy and biopsy. All results of the colposcopy and microendoscopy images were compared to the histopathological diagnosis. RESULTS: Characteristics of pathological blood vessels were easily distinguished by microendoscopy compared with ordinary colposcopy. The diagnostic agreement rate of microendoscopy with the pathological diagnosis was higher (95.3%) than that of ordinary colposcopy (37.7%) (weighted kappa = 0.863, P < .01). When diagnosing HSIL and more advanced disease, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the microendoscopic diagnosis were significantly higher than those of ordinary colposcopy (97.6 and 38.1%), (95.5 and 63.6%), (98.8 and 80.0%), (91.3 and 21.2%) and (97.7 and 43.4%), respectively. CONCLUSION: This study shows that microendoscopy has important value in the diagnosis of cervical lesions which can provide real-time diagnosis in vivo without staining, particularly for lesions that are not sensitive to acetic acid staining.

[Statistics and Analysis of 136 Cases of Adverse Events of International Medical Devices].

To explore the law and characteristics of adverse events of medical devices and to provide research methods and basis for reducing the recurrence of similar adverse events, we collect medical devices safety information from five representative countries in the world, and make statistics and analysis on the types of events, the types of management and the causes of events. The results show that among 136 serious adverse events, the top three causes of recall are product design factors, software factors, and component defects. In order to reduce the application risk of medical devices, it is suggested that product designers, operating users and medical institutions should correctly implement the monitoring and evaluation system of medical devices.

An improved LC-MS/MS method for the determination of mangiferin in rat plasma and its application in nonlinear pharmacokinetics.

A rapid and sensitive LC-MS/MS method was developed and validated for the determination of mangiferin in rat plasma. After simple protein precipitation of the plasma sample (100 microL) with 120 microL acetonitrile containing the internal standard rutin (500 ng/mL), the analytes were separated on a Zorbax SB-C18 column (150 x 2.1 mm, 3.5 microm) using an eluent of acetonitrile-0.05% formic acid in water (18:82, v/v), and then detected by electrospray ionization mass spectrometry in the negative multiple reaction monitoring mode with a chromatographic run time of 3.0 min. The method was sensitive, with a lower limit of quantification of 1 ng/mL and good linearity (r > 0.998) over the range of 1-250 ng/mL. It was also specific, precise and accurate when it was used to measure mangiferin levels in plasma and to characterize the pharmacokinetic properties following oral administration of mangiferin at a single dose of 5, 15, 45 and 90 mg/kg in rats. In addition, the pharmacokinetics of mangiferin were found to be nonlinear over the above dose range, which provides insight into dose regimen design of this potent compound in new drug development.

The regulation of intestinal flora on host's genes may play an essential role in the development of endometrial hyperplastic processes in yang deficiency individuals.

Yang-deficiency constitution (YADC) is linked to a higher vulnerability to various diseases, such as cold coagulation and blood stasis (CCBS) syndrome and infertility. Endometrial hyperplastic processes (EHPs) are a leading cause of infertility in women and are characterized by CCBS. However, it remains unclear whether YADC is related to the development of EHPs. METHODS: We recruited 202 EHPs patients including 147 with YADC (YEH group) and 55 with non-YADC (NYEH group). Fecal samples were collected from 8 YEH patients and 3 NYEH patients and analyzed using 16S rRNA V3-V4 sequencing for gut microbiota analysis. We obtained constitution survey data and a differential gut microbiota dataset from the literature for further analysis. Bioinformatics analysis was conducted using gut microbiota-related genes from public databases. RESULTS: YADC was significantly more prevalent in EHPs than non-YADC (P < 0.001), suggesting it as a potential risk factor for EHPs occurrence (ORpopulation survey = 13.471; ORhealthy women = 5.173). The YEH group had higher levels of inflammation, estrogen, and tamoxifen-related flora compared to NYEH and healthy YADC groups. There was an interaction between inflammation, estrogen, differential flora, and EHPs-related genes, particularly the TNF gene (related to inflammation) and the EGFR gene (related to estrogen), which may play a crucial role in EHPs development. CONCLUSION: YEH individuals exhibit significant changes in their gut microbiota compared to NYEH and healthy YADC. The interaction between specific microbiota and host genes is believed to play a critical role in the progression of EHPs.

Effects of low-level laser on the expression of interleukin-6, tumor necrosis factor­α, osteoprotegerin, and receptor activator of nuclear factor-κB ligand in human periodontal ligament cells.

OBJECTIVES: This study aims to determine the effects of low-level laser (LLL) on the expression of interleukin-6 (IL-6), tumor necrosis factor (TNF)-α, osteoprotegerin (OPG), and receptor activator of nuclear factor-κB ligand (RANKL) in human periodontal ligament cells (HPDLCs) stimulated by high glucose; and identify the molecular mechanism of LLL therapy in the regulation of periodontal inflammation and bone remodeling during orthodontic treatment in diabetic patients. METHODS: HPDLCs were cultured in vitro to simulate orthodontic after loading and irradiated with LLL therapy. The cultured cells were randomly divided into four groups: low glucose Dulbecco's modification of Eagle's medium (DMEM)+stress stimulation (group A), high glucose DMEM+stress stimulation (group B), hypoglycemic DMEM+LLL therapy+stress stimulation (group C), and hyperglycemic DMEM+LLL therapy+stress stimulation (group D). Groups C and D were further divided into C1 and D1 (energy density: 3.75 J/cm2) and C2 and D2 (energy density: 5.625 J/cm2). Cells in groups A, B, C, and D were irradiated by LLL before irradiation. At 0, 12, 24, 48, and 72 h, the supernatants of the cell cultures were extracted at regular intervals, and the protein expression levels of IL-6, TNF-α, OPG, and RANKL were detected by enzyme-linked immunosorbent assay. RESULTS: 1) The levels of IL-6 and TNF-α secreted by HPDLCs increased gradually with time under static pressure stimulation. After 12 h, the levels of IL-6 and TNF-α secreted by HPDLCs in group A were significantly higher than those in groups B, C1, and C2 (P<0.05), which in group B were significantly higher than those in groups D1, and D2 (P<0.01). 2) The OPG protein concentration showed an upward trend before 24 h and a downward trend thereafter. The RANKL protein concentration increased, whereas the OPG/RANKL ratio decreased with time. Significant differen-ces in OPG, RANKL, and OPG/RANKL ratio were found among group A and groups B, C1, C2 as well as group B and groups D1, D2 (P<0.05). CONCLUSIONS: 1) In the high glucose+stress stimulation environment, the concentrations of IL-6 and TNF-α secreted by HPDLCs increased with time, the expression of OPG decreased, the expression of RANKL increased, and the ratio of OPG/RANKL decreased. As such, high glucose environment can promote bone resorption. After LLL therapy, the levels of IL-6 and TNF-α decreased, indicating that LLL therapy could antagonize the increase in the levels of inflammatory factors induced by high glucose environment and upregulate the expression of OPG in human HPDLCs, downregulation of RANKL expression in HPDLCs resulted in the upregulation of the ratio of OPG/RANKL and reversed the imbalance of bone metabolism induced by high glucose levels. 2) The decrease in inflammatory factors and the regulation of bone metabolism in HPDLCs were enhanced with increasing laser energy density within 3.75-5.625 J/cm2. Hence, the ability of LLL therapy to modulate bone remodeling increases with increasing dose.

Disordered Expression of Tight Junction Proteins Is Involved in the Mo-induced Intestinal Microenvironment Dysbiosis in Sheep.

To evaluate the molybdenum (Mo)-induced changes of intestinal morphology and the relationship of intestinal tight junction (TJ) proteins expression and intestinal barrier function, a total of 20 healthy sheep were randomly divided into five groups of four: 0, 5, 10, 20, and 50 mg/kg BW/day Na2MoO4·2H2O were administrated in five groups named control group, Mo 5 group, Mo 10 group, Mo 20 group, and Mo 50 group, respectively. After 28 days of Mo treatment, the duodenum, the jejunum, and the ileum tissue were collected. The histopathology and the developmental parameters were evaluated by hematoxylin-eosin staining. The intestinal epithelial cell DNA damage was detected by TdT-mediated dUTP nick end labeling assay. The intestinal glycoprotein and the goblet cells were analyzed by Alcian Blue-Periodic Acid-Schiff (AB-PAS) staining and PAS staining, respectively. TJ proteins were determined by immunofluorescence technology. Results showed that excessive Mo significantly decreased the small intestinal villus height (VH), crypt depth (CD), VH/CD, and mucosal thickness (P < 0.05 or P < 0.01) while induced the damage of DNA in small intestinal epithelial cells. Moreover, excessive Mo injured intestinal barrier function by decreasing the percent of glycoprotein distribution area (P < 0.05) and the relative density of intestinal goblet cells (P < 0.05). Mo treatment induced decreased (P < 0.01) expression of Zonula Occludens-1, Occludin, and Claudin-1. In conclusion, excessive Mo interfered with the expression of TJ proteins, inhibited intestinal epithelial development, and further aggravated the intestinal barrier function damage, leading to disturbing the small intestinal microenvironment balance.

Immunogenicity and efficacy of serogroup A and D bacterins against Pasteurella multocida in mice.

Introduction: Pasteurella multocida is a widespread respiratory pathogen in pigs, causing swine pneumonia and atrophic rhinitis, and the capsular serogroups A and D are the main epidemic serogroups in infected animals. This study investigated the protective effects of serogroup A and D bacterins against current circulating P. multocida strains, to better understand the immunity generated by bacterins. Method: 13 serogroup A (seven A: L3 and six A: L6 strains) and 13 serogroup D (all D: L6 strains) P. multocida strains were isolated, and used as inactivated whole cell antigen to prepare P. multocida bacterins. Mice were immunized with these bacterins at 21-day interval and intraperitoneally challenged with the homologous and heterologous P. multocida strains, respectively. The antibody titer levels and immunization protective efficacy of vaccines were evaluated. Results: All of the bacterins tested induced high titer levels of immunoglobulin G antibodies against the parental bacterial antigen in mice. Vaccination with the six A: L6 bacterins provided no protection against the parent strain, but some strains did provide heterologous protection against A: L3 strains. Vaccination with the seven A: L3 bacterins provided 50%-100% protection against the parent strain, but none gave heterologous protection against the A:L6 strains. Immunization with the thirteen D: L6 bacterins offered 60%-100% protection against the parent strain, and almost all D: L6 strains gave cross-protection. Discussion: This study found that the cross-protectivity of serogroup A strains was poor, while serogroup D strains was effective, which provided some insights for P. multocida vaccine development.

Chronic heat stress induces lung injury in broiler chickens by disrupting the pulmonary blood-air barrier and activating TLRs/NF-κB signaling pathway.

As an important respiratory organ, the lung is susceptible to damage during heat stress due to the accelerated breathing frequency caused by an increase in environmental temperature. This can affect the growth performance of animals and endanger their health. This study aimed to explore the mechanism of lung tissue damage caused by heat stress. Broilers were randomly divided into a control group (Control) and a heat stress group (HS). The HS group was exposed to 35°C heat stress for 12 h per d from 21-days old, and samples were taken from selected broilers at 28, 35, and 42-days old. The results showed a significant increase in lactate dehydrogenase (LDH) activity in the serum and myeloperoxidase (MPO) activity in the lungs of broiler chickens across all 3 age groups after heat stress (P < 0.01), while the total antioxidant capacity (T-AOC) was significantly enhanced at 35-days old (P < 0.01). Heat stress also led to significant increases in various proinflammatory factors in serum and expression levels of HSP60 and HSP70 in lung tissue. Histopathological results showed congestion and bleeding in lung blood vessels, shedding of pulmonary epithelial cells, and a large amount of inflammatory infiltration in the lungs after heat stress. The mRNA expression of TLRs/NF-κB-related genes showed an upward trend (P < 0.05) after heat stress, while the mRNA expression of MLCK, a gene related to pulmonary blood-air barrier, significantly increased after heat stress, and the expression levels of MLC, ZO-1, and occludin decreased in contrast. This change was also confirmed by Western blotting, indicating that the pulmonary blood-air barrier is damaged after heat stress. Heat stress can cause damage to the lung tissue of broiler chickens by disrupting the integrity of the blood-air barrier and increasing permeability. This effect is further augmented by the activation of TLRs/NF-κB signaling pathways leading to an intensified inflammatory response. As heat stress duration progresses, broiler chickens develop thermotolerance, which gradually mitigates the damaging effects induced by heat stress.

Effects of N-n-butyl haloperidol iodide on the rat myocardial sarcoplasmic reticulum Ca(2+)-ATPase during ischemia/reperfusion.

We have previously shown that N-n-butyl haloperidol iodide (F(2)), a newly synthesized compound, reduces ischemia/reperfusion (I/R) injury by preventing intracellular Ca(2+) overload through inhibiting L-type calcium channels and outward current of Na(+)/Ca(2+) exchanger. This study was to investigate the effects of F(2) on activity and protein expression of the rat myocardial sarcoplasmic reticulum Ca(2+)-ATPase (SERCA) during I/R to discover other molecular mechanisms by which F(2) maintains intracellular Ca(2+) homeostasis. In an in vivo rat model of myocardial I/R achieved by occluding coronary artery for 30-60 min followed by 0-120 min reperfusion, treatment with F(2) (0.25, 0.5, 1, 2 and 4 mg/kg, respectively) dose-dependently inhibited the I/R-induced decrease in SERCA activity. However, neither different durations of I/R nor different doses of F(2) altered the expression levels of myocardial SERCA2a protein. These results indicate that F(2) exerts cardioprotective effects against I/R injury by inhibiting I/R-mediated decrease in SERCA activity by a mechanism independent of SERCA2a protein levels modulation.

Two new oleanane-type triterpenoids from Platycodi Radix and anti-proliferative activity in HSC-T6 cells.

Two new oleanane-type triterpenoids, named platycodonoids A and B (1, 2), together with five known saponins, including platycodin D (3), deapioplatycodin D (4), 3-O-ß-D-glucopyranosyl polygalacic acid (5), 3-O-ß-D-glucopyranosyl platycodigenin (6) and polygalacin D (7), were isolated from the roots of Platycodon grandiflorum. On the basis of spectral data and chemical evidence, the structures of the new compounds were elucidated as 2ß,3ß,23,24-tetrahydroxy-28-nor-olean-12-en-16-one (1) and 2ß,3ß,23,24- tetrahydroxy-28-nor-olean-12-en-16-one-3-O-ß-D-glucopyranoside (2). Compounds 1-7 were evaluated for their in vitro anti-proliferative activity against the HSC-T6 cell line.

Screening immune adjuvants for an inactivated vaccine against Erysipelothrix rhusiopathiae.

In this study, we screened adjuvants for an inactivated vaccine against Erysipelothrix rhusiopathiae (E. rhusiopathiae). Inactivated cells of E. rhusiopathiae strain HG-1 were prepared as the antigen in five adjuvanted inactivated vaccines, including a mineral-oil-adjuvanted vaccine (Oli vaccine), aluminum-hydroxide-gel-adjuvanted vaccine (Alh vaccine), ISA201-biphasic-oil-emulsion-adjuvanted vaccine (ISA201 vaccine), GEL02-water-soluble-polymer-adjuvanted vaccine (GEL vaccine), and IMS1313-water-soluble-nanoparticle-adjuvanted vaccine (IMS1313 vaccine). The safety test results of subcutaneous inoculation in mice showed that Oli vaccine had the most severe side effects, with a combined score of 35, followed by the ISA201 vaccine (25 points), Alh vaccine (20 points), GEL vaccine (10 points), and IMS1313 vaccine (10 points). A dose of 1.5LD50 of strain HG-1 was used to challenge the mice intraperitoneally, 14 days after their second immunization. The protective efficacy of Oli vaccine and Alh vaccine was 100% (8/8), whereas that of the other three adjuvanted vaccines was 88% (7/8). Challenge with 2.5LD50 of strain HG-1 resulted in a 100% survival rate, demonstrating the 100% protective efficacy of the Oli vaccine, followed by the GEL vaccine (71%, 5/7), IMS1313 vaccine (57%, 4/7), ISA201 vaccine (43%, 3/7), and Alh vaccine (29%, 2/7). Challenge with 4LD50 of strain HG-1 showed 100% (7/7) protective efficacy of the Oli vaccine and 71% (5/7) protective efficacy of the GEL vaccine, whereas the protective efficacy of other three adjuvanted vaccine was 14% (1/7). The Alh and GEL vaccines were selected for comparative tests in piglets, and both caused minor side effects. A second immunization with these two adjuvanted vaccines conferred 60 and 100% protective efficacy, respectively, after the piglets were challenged via an ear vein with 8LD100 of strain HG-1. After challenge with 16LD100 of strain HG-1, the Alh and GEL vaccines showed 40% and 100% protective efficacy, respectively. Our results suggested that GEL is the optimal adjuvant for an inactivated vaccine against E. rhusiopathiae.

Low-defect-density WS2 by hydroxide vapor phase deposition.

Two-dimensional (2D) semiconducting monolayers such as transition metal dichalcogenides (TMDs) are promising channel materials to extend Moore's Law in advanced electronics. Synthetic TMD layers from chemical vapor deposition (CVD) are scalable for fabrication but notorious for their high defect densities. Therefore, innovative endeavors on growth reaction to enhance their quality are urgently needed. Here, we report that the hydroxide W species, an extremely pure vapor phase metal precursor form, is very efficient for sulfurization, leading to about one order of magnitude lower defect density compared to those from conventional CVD methods. The field-effect transistor (FET) devices based on the proposed growth reach a peak electron mobility ~200 cm2/Vs (~800 cm2/Vs) at room temperature (15 K), comparable to those from exfoliated flakes. The FET device with a channel length of 100 nm displays a high on-state current of ~400 µA/µm, encouraging the industrialization of 2D materials.

N-n-butyl haloperidol iodide preserves cardiomyocyte calcium homeostasis during hypoxia/ischemia.

AIMS: N-n-Butyl haloperidol iodide (F(2)) is a novel compound derived from haloperidol. In our previous work, F(2) was found to be an L-type calcium channel blocker which played a protective role in rat heart ischemic-reperfusion injury in a dose-dependent manner. In the current study, we aimed to investigate the effects and some possible mechanisms of F(2) on calcium transients in hypoxic/ischemic rat cardiac myocytes. METHODS AND RESULTS: Calcium transients' images of rat cardiac myocytes were recorded during simulated hypoxia, using a confocal calcium imaging system. The amplitude, rising time from 25% to 75% (RT25-75), decay time from 75% to 25% (DT75-25) of calcium transients, and resting [Ca(2+)](i) were extracted from the images by self-coding programs. In this study, hypoxia produced a substantial increase in diastolic [Ca(2+)](i) and reduced the amplitude of calcium transients. Both RT25-75 and DT75-25 of Ca(2+) transients were significantly prolonged. And F(2) could reduce the increase in resting [Ca(2+)](i)and the prolongation of RT25-75 and DT75-25 of Ca(2+) transients during hypoxia. F(2) also inhibited the reduction in amplitude of calcium transients which was caused by 30-min hypoxia. The activity of SERCA2a (sarcoplasmic reticulum Ca(2+)-ATPase, determined by test kits) decreased after 30-min ischemia, and intravenous F(2) in rats could ameliorate the decreased activity of SERCA2a. The inward and outward currents of NCX (recorded by whole-cell patch-clamp analysis) were reduced during 10-min hypoxia, and F(2) further inhibited the outward currents of NCX during 10-min hypoxia. All these data of SERCA2a and NCX might be responsible for the changes in calcium transients during hypoxia. CONCLUSION: Our data suggest that F(2) reduced changes in calcium transients that caused by hypoxia/ischemia, which was regarded to be a protective role in calcium homeostasis of ventricular myocytes, probably via changing the function of SERCA2a.

[Effect of curcumin on the expression of high mobility group box 1 and apoptotic neurons in hippocampus after global cerebral ischemia reperfusion in rats].

OBJECTIVE: To explore the effects of curcumin on the expression of high mobility group box 1 (HMGB1) and apoptotic neurons in hippocampus after global cerebral ischemia/reperfusion in SD rats. METHODS: A total of 192 male SD rats were randomly divided into 4 groups: sham group (SH), ischemia-reperfusion group (IR), curcumin group (Cur) and solvent control group (SC). Bilateral vertebrate arteries were electrocauterized and bilateral common carotid arteries liberated in 3 ischemic groups. Isasteric curcumin solutions (200 mg/kg) or menstruum were injected intraperitoneally at 1 hour pre-ischemia in Cur and SC groups. The rats in each group were ligated for 15 minutes and then decapitated at 1, 3, 5 and 7 d post-reperfusion respectively. Cell morphology was observed on hematoxylin & eosin-stained slides. Apoptotic neurons were detected in CA1 region by TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling). Western blot was used to make a semi-determination of HMGB1 expression. RESULTS: At each time point, the number of apoptotic neurons was much more in IR and SC groups than that in SH group (P < 0.05). And the number of apoptotic neurons at 1, 3, 5, 7 d post-reperfusion was only 41%, 57%, 65% and 70% in Cur group respectively (P < 0.05). The expressional level of HMGB1 in IR and SC groups was significantly lower at 1d post-reperfusion (0.685 ± 0.050; 0.695 ± 0.053 vs 0.977 ± 0.063, P < 0.05). And it was significantly higher at 3, 5, 7 d post-reperfusion in IR and SC groups than that in SH groups (1.360 ± 0.045/1.353 ± 0.045; 1.342 ± 0.046/1.338 ± 0.047; 1.319 ± 0.052/1.322 ± 0.035 vs 0.992 ± 0.031; 0.978 ± 0.090; 0.992 ± 0.075, P < 0.05). The level at 1 d post-reperfusion (0.842 ± 0.063) in Cur group was significantly higher than that in IR and SC groups but lower than that in SH group. And it was lower at 3, 5, 7 d post-reperfusion (1.125 ± 0.023, 1.098 ± 0.073, 1.087 ± 0.089) than those in IR and SC groups (P < 0.05). There was no significant difference of HMGB1expression level between IR and SC groups. CONCLUSION: The expression level of HMGB1 in hippocampus is significantly reduced at 1 d post-reperfusion. Then it significantly increases and a high level is maintained until 7 d after global cerebral ischemia/reperfusion. Curcumin can reduce hippocampal neuronal apoptosis and injury. Such an effect may be due to an inhibition of the synthesis and release of HMGB1.

The Influence of Autoclaving on Diamond Burs Fabricated via Different Methods.

PURPOSE: To evaluate the influence of repetitive autoclaving on diamond burs fabricated via different methods. MATERIALS AND METHODS: A total of 96 diamond burs were divided into 12 groups according to fabrication method (single-element electroplating, multi-element electroplating, or brazing) and number of times autoclaved (0, 5, 10, or 15). The surface characteristics and components of the diamond burs were examined using scanning electron microscopy (SEM) and x-ray photoelectron spectroscopy (XPS). The cutting efficiency of the diamond burs was tested with a constant-pressure cutting appliance. RESULTS: Compared to the nonautoclaved group, the cutting efficiency of the multi-element and single-element electroplated diamond burs decreased significantly after autoclaving 5, 10, and 15 times (P < .05). The cutting efficiency of the brazed diamond burs started to decrease significantly after 10 cycles (P < .05). Cracks appeared on the surfaces of multi-element electroplated diamond burs after 10 and 15 cycles, but were absent in the single-element electroplated and brazed diamond burs. A reduction of nickel was detected in the multi-element electroplated and brazed diamond burs, but not in the single-element electroplated diamond burs. CONCLUSION: Repetitive autoclaving could reduce the cutting efficiency of diamond burs. The extent of the reduction was related to fabrication method and number of autoclaving times, suggesting that used diamond burs should be separately autoclaved to avoid shortening the life spans of unused ones.

Structural and Secondary Electron Yield Properties of Titanium-Palladium Films with Laser-Treated Copper Substrate for Application in Neutron Generators.

Secondary electron emission (SEE) of the oxygen-free high-conductivity copper (OFHC) target surface in neutron generators limits the stability and improvement of the neutron yield. A novel-type target of titanium-palladium films coated on laser-treated OFHC target substrate was proposed and explored in this work to obtain low secondary electron yield (SEY) without introducing any components. The combination of Ti-Pd films and laser-treated OFHC substrate can effectively suppress secondary electron emission and enhance the adsorption ability to hydrogen isotopes with the existence of Pd film. The surface morphologies, surface chemical states, and SEYs of Ti-Pd films with laser-treated OFHC substrate were studied systematically for the first time. The XPS results showed that the laser-treated OFHC substrate surface was basically covered by Pd film. However, the Pd film surface was partially oxidized, with percentages of 21.31 and 10.02% for PdO and PdO2, respectively. The SEYs of Ti-Pd films with laser-treated OFHC substrate were all below 1 within the investigated primary energy range of 100-3000 eV, which would be sufficient for application in neutron generators. Specifically, the maximum SEY (δmax) of laser-treated OFHC substrate coated by Ti-Pd films was 0.87 with corresponding incident electron energy of 400 eV.