Objective To clarify the understanding of types of laboratories and manufacturers for GB 9706.1-2020 Medical electrical equipment-Part 1:General requirements for basic safety and essential performance by laboratory proficiency testing for creepage distance and electrical clearance test.Methods An operation guide was formed according to the testing program in GB 9706.1-2020,and the homogeneity and stability of the samples were evaluated according to CNAS-GL003:2018 Guidance on Evaluating the Homogenneity and Stability of Samples Used for Proficiency Testing.Robust statistic methods were used to assess the quantitative parameters of the test results of the participating laboratories according to the requirements in GB/T 28043-2019 Statistical methods for use in proficiency testing by interlaboratory comparison;the results reported by the expert laboratories were used as the specified values of the qualitative parameters.SPSS 25.0 statistical software was used for data analysis.Results All the results of the crreepage distance and electrical clearance tests met the requirements for homogeneity and stability.Of the 46 laboratories involved in,37 ones did have comprehensive satisfactory determinations while the remained 9 ones not.Conclusion Some laboratories don't behave well in understanding the standard,which have to be reformed accordingly to enhance their proficiencies.[Chinese Medical Equipment Journal,2024,45(10):54-59]

OBJECTIVETo investigate the changes in phosphorylated JAK2 and STAT3 protein expression of and cell apoptosis following focal cerebral ischemia-reperfusion injury in rats.

METHODSA rat models of focal cerebral ischemia-reperfusion injury was established by middle cerebral artery occlusion using modified filament method. Immunohistochemistry and Western blot analysis were used to detect the expression of P-JAK2 and P-STAT3 proteins, and TUNEL assay was employed to examine the cell apoptosis.

RESULTSP-JAK2 and P-STAT3 protein expression increased significantly after cerebral ischemia-reperfusion injury in rats. The immunoreactivity was prominent in the peripheral of the ischemic region and reached the peak level at 24 h of reperfusion, followed by slight decrement. The apoptotic cells increased obviously after cerebral ischemia-reperfusion injury, also reaching the peak level at 24 h of reperfusion.

CONCLUSIONThe expression of phosphorylated JAK2 and STAT3 may be involved in the ischemic cellular events including apoptosis. JAK2/STAT3 signaling pathway plays a role in the pathophysiological process of cerebral ischemia/reperfusion cell injury and repair.

Animals ; Apoptosis ; Blotting, Western ; Immunohistochemistry ; In Situ Nick-End Labeling ; Infarction, Middle Cerebral Artery ; physiopathology ; Janus Kinase 2 ; metabolism ; Male ; Phosphorylation ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; genetics ; physiopathology ; STAT3 Transcription Factor ; metabolism

Objective To explore the effect of edaravone (ED) on the neurological functionaldeficits, apoptosis and expression of caspase-3 protein following focal cerebral ischemia/reperfusion(I/R)injury in rats. Methods A total of 24 male Sprague-Dawley (SD) rats were randomly allocated intothe sham-operation group, cerebral I/R group, normal saline treatment group and ED treatment group, 6rats in each group. Rat models with focal cerebral I/R injury induced by middle cerebral artery occlusion(MCAO) were established using a modified suture method. ED (3mg/kg) or equal volume of normalsaline was injected intraperitoneally immediately after cerebral ischemia and 12 h after reperfusion in thetreatment groups;the rats in sham-operation group underwent the same modeling procedure withoutischemia by nylon suture. The neurological behavioral deficits were evaluated 24 h after I/R injury;,immunohistochemical staining and Western blot assay were applied to detect the change in the expressionof caspase-3 protein; in situ TdT-mediated dUTP-biotin nick end labeling (TUNEL) assay was used tostudy the change in neuronal apoptosis. Results The scores of neurological behavioral deficit scale,the positive cells and expression of caspase-3 protein, and the apoptotic cells in the ED treatment groupwere significantly decreased, compared with that of the I/R group and normal saline treatment group(P<0.05 for each comparison). Conclusion ED may effectively reduce neuronal apuptosis andneurological functional deficits after cerebral I/R injury, which might be related with the inhibition of thecaspase-3 protein expression.

OBJECTIVETo develop a colon-specific prodrug of Indomethacin microbially triggered, carry out in vitro/in vivo evaluation of drug release, and appraise its inhibitory effect on liver metastasis from colon cancer.

METHODSIndomethacin prodrugs were synthesized and characterized by FTIR and NMR, and dissolution test simulating gastrointestinal tract was employed to screen the colon-specific prodrug. Then, the pharmacokinetic profile of portal vein and peripheral blood in Sprague-Dawley rats was studied. Lastly, the inhibitory effect on liver metastasis from colon cancer in nude mice was observed.

RESULTSThe chemical structure characterized by FTIR and NMR demonstrated that six kinds of indomethacin-block-amylose with different drug loading (IDM-AM-1-6) were synthesized, among which IDM-AM-3 was degraded 1.3%, 9.3% and 95.3%, respectively, in simulated gastric fluid for 4 h, small intestine for 6 h, and colon for 36 h. The pharmacokinetic test of IDM-AM-3 showed that absorption was delayed significantly (P < 0.01), peak time [(11.35 + or - 2.45) h], elimination half-life [(16.74 + or - 4.04) h] and mean residence time [(22.27 + or - 0.52) h] were significantly prolonged (P < 0.01), as well as peak serum concentrations [(9.69 + or - 2.40) mg/L] and AUC(0-t) [(236.7 + or - 13.1) mg x L(-1) x h] were decreased markedly (P < 0.01) as compared with those of IDM regarding to portal vein. Additionally, its AUC(0-t) in peripheral blood was remarkably lower than that in Portal vein (P < 0.01). The tumor suppression observation showed that it could remarkably reduce the number of liver metastases in contrast to IDM (P < 0.05).

CONCLUSIONColon-specific IDM-AM-3 possesses advantage of sustained release in portal vein providing some experimental basis for colon-specific delivery system applied to sustained release in the portal vein.

Amylose ; administration & dosage ; chemical synthesis ; pharmacokinetics ; therapeutic use ; Animals ; Colon ; metabolism ; Colonic Neoplasms ; pathology ; Delayed-Action Preparations ; Drug Delivery Systems ; HT29 Cells ; Humans ; Indomethacin ; administration & dosage ; chemical synthesis ; pharmacokinetics ; therapeutic use ; Liver Neoplasms ; prevention & control ; secondary ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Neoplasm Transplantation ; Prodrugs ; administration & dosage ; chemical synthesis ; pharmacokinetics ; therapeutic use ; Random Allocation ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo study the clinical features, treatment methods and outcome of solitary plasmacytoma of cervical spine.

METHODSFrom January 1995 to December 2007, the data of 23 cases with solitary plasmacytoma of cervical spine was analyzed. There were 16 males and 7 females (mean age 56 years, range: 32 - 76 years). Two cases underwent radiotherapy alone and 21 patients received surgery. According to WBB staging system, surgical procedures were defined as total or subtotal resection (6 cases), appendix resection (4 cases), sagittal resection (3 cases) and total spondylectomy (8 cases). All surgical cases were managed using an anterior approach, posterior approach or combined anterior and posterior approach. The cervical spinal reconstruction was achieved through anterior cervical titanium plate and titanium mesh cage filled with auto iliac graft or bone cement, or anterior and posterior combined instrumented fusion. All patients received radiotherapy as adjunctive therapy.

RESULTSFollow-up of the 23 cases lasted 24.0 - 143.0 months (mean: 64.7 months). Neck pains obviously improved, and nerve compression symptoms disappeared or improved after surgery. Neurological function improved by 1 - 2 grades based on Frankel grading system. All the internal fixations were fused well and stability of the cervical spine was fine and no spine instability could be seen in our series. The bone graft fusion rate was 100%. During the follow-up period, 6 surgical cases had local recurrence and finally progressed to multiple myeloma (MM) and 3 died. Two cases without surgical treatment progressed to MM in 1 year and 1.5 years after confirmed diagnosis. They were given systemic chemotherapy. The other 15 patients had disease-free survival and after surgery and adjunctive radiotherapy. Obvious abnormity were not found in such examinations as M protein, bone marrow aspiration and emission computed tomography or PET-CT examinations.

CONCLUSIONSSolitary plasmacytoma of cervical spine is rarely seen clinically. Surgery is recommended as the primary management for patients with overt bone destruction and spinal instability or neurological dysfunction. Tumor excision with adjunctive radiotherapy can obviously reduce local recurrences and lower the possibility of progression to MM. The patients with progression to MM should receive chemotherapy according to chemotherapy protocol while the prognosis is comparatively worse.

Adult ; Aged ; Cervical Vertebrae ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Plasmacytoma ; surgery ; Retrospective Studies ; Spinal Neoplasms ; surgery ; Treatment Outcome

To explore the effects of proteasome inhibitor PS-341 on the cytokine expressions of mesenchymal stem cells (MSC) in patients with multiple myeloma (MM), MSCs of 11 patients were cultured in medium of RPMI 1640 containing 10% FBS. When cells grew to 5 x 10(5) - 1 x 10(6), cells were exposed to 50 nmol/L PS-341 for 4 hours, then harvested. The expressions of IL-6, IL-1beta and SCF were detected by RT-PCR. The results indicated that after treatment with PS-341 the expressions of IL-6, IL-1beta and SCF of MSCs decreased markedly, especially that of IL-1beta, compared with control (P < 0.05, P < 0.01, P < 0.05, respectively). There were obviously differences of IL-1beta expression between refractory/relapsed group and complete remission (CR) group and IL-1beta expression was inhibited more seriously in CR group, whereas there were no significant differences of IL-6 and SCF expression between two groups; IL-1beta expression of patients treated with PS-341 was not detected; there were not effects of IL-1beta expression on expressions of IL-6 and SCF. It is concluded that proteasome inhibitor PS-341 downregulated the expressions of IL-6, IL-1beta and SCF of MSCs in patients with MM.
Antineoplastic Agents ; pharmacology ; Bone Marrow Cells ; metabolism ; pathology ; Boronic Acids ; pharmacology ; Bortezomib ; Cytokines ; biosynthesis ; Humans ; Interleukin-1beta ; biosynthesis ; Interleukin-6 ; biosynthesis ; Mesenchymal Stromal Cells ; metabolism ; Multiple Myeloma ; metabolism ; pathology ; Protease Inhibitors ; pharmacology ; Pyrazines ; pharmacology ; Stem Cell Factor ; biosynthesis

OBJECTIVETo evaluate the effects of Tanguticum Maxim polysaccharide (TMP-1) on TNBS-induced colitis in rats.

METHODRats with TNBS/ethanol-induced colitis were used and treated with TMP-1 and dexamethasone (DX). Seventy-two rats, including animals with TNBS-induced colitis, were treated with saline, TMP-1 (100, 200, 400 mg.kg-1) and DX. White blood cells were counted on the fifth day and the rats were killed by ether on the sixth day. SOD activity in serum, MPO and SOD activity of colonic tissue were measured.

RESULTThe remarkable effects of TMP-1 at dosage of 200, 400 mg.kg-1 on TNBS-induced colitis were observed. The ulcerative area was diminished and weight of colon was reduced. White blood cell population was reduced, SOD activity in serum and SOD activity of colon tissue were remarkably increased, and, MPO activity of colonic tissue was reduced.

CONCLUSIONTMP-1 has significant effects on TNBS-induced colitis in rats with lower side effects, which suggests the effective component of rhubarb on colitis perhaps is TMP. The mechanism of the actions of TMP may relate to its antiflammation, antioxidation and immunoloregulation.

Animals ; Anti-Inflammatory Agents, Non-Steroidal ; therapeutic use ; Colitis, Ulcerative ; chemically induced ; drug therapy ; Colon ; enzymology ; pathology ; Male ; Phytotherapy ; Plants, Medicinal ; chemistry ; Polysaccharides ; isolation & purification ; therapeutic use ; Rats ; Rats, Sprague-Dawley ; Rheum ; chemistry ; Trinitrobenzenesulfonic Acid

OBJECTIVETo investigate the antibacterial effects of zirconium phosphate gauze loaded with silver on rat burn wounds seeded with commonly seen bacteria.

METHODSWistar rats were employed in the study and were scalded and infected. The minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) of zirconium phosphate loaded with silver were determined by double dilution in tubes. The effect on wound healing and the subeschar bacterial count of the rat burn wounds were observed after the wounds had been covered by gauze loaded with zirconium phosphate and silver, and also with the gauze which has been rinsed for 20 times.

RESULTSThe MIC of silver loaded zirconium phosphate on Staphylococcus aureus, Pseudomonas aeruginosa and E. coli were 8, 8 and 16 mg/L, respectively, while the MBC were 16, 8 and 32 mg/L, respectively. The subeschar bacterial count in the burn wounds with the gauze with silver loaded zirconium phosphate was ten times lower than that in those which were treated with gauze with SD-Ag and 100 times lower than that with ordinary gauze. But there was no difference in the bacterial count between the wounds which were treated with fresh gauze with silver loaded zirconium phosphate and that with the gauze which has been rinsed for 20 times (P > 0.05). Furthermore, wound healing seemed to be better with the gauze with silver loaded zirconium phosphate when compared with those by the other two kinds of gauze.

CONCLUSIONThe silver loaded zirconium phosphate was found to be bacteriocidal against bacteria commonly seen in the burn wounds.

Animals ; Anti-Bacterial Agents ; administration & dosage ; pharmacology ; Bandages ; Burns ; microbiology ; therapy ; Colony Count, Microbial ; Female ; Male ; Rats ; Rats, Wistar ; Silver ; administration & dosage ; pharmacology ; Wound Healing ; drug effects ; Wound Infection ; microbiology ; therapy ; Zirconium ; administration & dosage ; pharmacology

To investigate the influence of As2O3, dexamethasone (Dex) and thalidomide (Thal) on apoptosis-induced myeloma cell line U266 cytoplasmic calcium concentrations ([Ca2+]i), U266 cells were incubated in the culture of RPMI 1640 with 15% FBS in 24-well plate and exposed to different concentrations of As2O3, Dex and Thal for 8 hours, respectively, then cell apoptosis was analyzed by fluorescence microscopy and flow cytometry (FCM) with Annexin V-FITC/PI double staining, and cytoplasmic free calcium were detected on FCM through Fluo-3/AM loading. The results indicated that (1) apoptotic cells were gradually increased with enhancement of As2O3, Dex and Thal concentrations; (2) apoptotic cell rates increased from 0.56% in control to 31.54%, 28.35% and 21.97% respectively after treatment with As2O3, Dex and Thal; (3) As2O3, Dex induced U266 cell apoptosis accompanied with raise of [Ca2+]i; (4) [Ca2+]i had no statistically significant changes in Thal-induced apoptotic U266 cells. It is concluded that the raise of [Ca2+]i is one of the mechanisms for As2O3 and Dex-induced U266 cells apoptosis, whereas Thal-induced U266 apoptosis has no significant relation to [Ca2+]i changes.
Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Arsenicals ; pharmacology ; Calcium ; metabolism ; Cell Line, Tumor ; Cytoplasm ; metabolism ; Dexamethasone ; pharmacology ; Humans ; Multiple Myeloma ; pathology ; Oxides ; pharmacology ; Thalidomide ; pharmacology

OBJECTIVESTo understand the epidemiological characteristics of severe acute respiratory syndrome (SARS) outbreaks in some areas of Guangdong province and to provide scientific basis for prevention and control measures against it.

METHODSStandardized questionnaire was used on individual cases. Data on the epidemiological characteristics as time, place, persons and aggregation status of SARS cases, development of the epidemics, were analyzed with software EPI 6.0.

RESULTSThe incidence of SARS in Guangdong province was 1.72/100,000 with case fatality rate as 3.64%. Most cases of SARS occurred between the last ten days of January and the first ten days of February with the peak (61.88% of the patients) occurred in the first ten days of February. As to the distribution of place, Pearl river delta region-economically developed with great number of mobile population-was heavily affected areas (account for 96.66% of the total patients). The majority of patients were young adults and medical staff seemed to be the most affected subgroup (account for 24.9% of the patients in total). Family and hospital aggregation of patients comprised the another two important characteristics of SARS (account for 37.1% of the total patients).

CONCLUSIONCurrent knowledge on SARS suggested that it was an air-borne infectious disease with human beings served as the source of infection. The incubation period of the disease was from 1 to 12 days with a median of 4 days. Respiratory secretions and close contact contributed to person-to-person transmission. Most cases were distributed in Pearl river delta region, an area famous for its economic development and heavy flow of mobile population.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; China ; epidemiology ; Contact Tracing ; Disease Outbreaks ; Family Health ; Female ; Humans ; Incidence ; Infectious Disease Transmission, Patient-to-Professional ; Male ; Middle Aged ; Retrospective Studies ; Severe Acute Respiratory Syndrome ; epidemiology ; mortality ; Surveys and Questionnaires