Treatment for Covid-19 with SARS-CoV-2 neutralizing antibody BRII-196(Ambavirumab) plus BRII-198(Lomisivir): a retrospective cohort study.

BACKGROUND: Monoclonal antibody therapy for Covid-19 springs up all over the world and get some efficiency. This research aims to explore the treating effect of BRII-196(Ambavirumab) plus BRII-198(Lomisivir) on Covid-19. METHODS: In this retrospective cohort research, patients received standard care or plus BRII-196 /BRII-198 monoclonal antibodies. General comparison of clinical indexes and prognosis between Antibody Group and Control Group was made. Further, according to the antibody using time and patients' condition, subgroups included Early antibody group, Late antibody group, Mild Antibody Group, Mild Control Group, Severe Antibody Group and Severe Control Group. RESULTS: Length of stay(LOS) and interval of Covid-19 nucleic acid from positive to negative of Antibody Group were 12.0(IQR 9.0-15.0) and 14.0(IQR 10.0-16.0) days, less than those(13.0 (IQR 11.0-18.0) and 15.0 (IQR 12.8-17.0) days) of Control Group(p = 0.004, p = 0.004). LOS(median 10days) of Early Antibody Group was the shortest, significantly shorter than that of Control Group (median 13days)(p < 0.001). Interval(median 12days) of Covid-19 nucleic acid from positive to negative of Early Antibody Group also was significantly shorter than that of Control Group(median 15days) and Late Antibody Group(median 14days)(p = 0.001, p = 0.042). LOS(median 12days) and interval(median 13days) of Covid-19 nucleic acid from positive to negative of Mild Antibody Group was shorter than that of Mild Control Group(median 13days; median 14.5days)(p = 0.018, p = 0.033). CONCLUSION: The neutralizing antibody therapy, BRII-196 plus BRII-198 could shorten LOS and interval of Covid-19 nucleic acid from positive to negative. However, it didn't show efficacy for improving clinical outcomes among severe or critical cases.

GKK1032B from endophytic Penicillium citrinum induces the apoptosis of human osteosarcoma MG63 cells through caspase pathway activation.

Chemical investigation of the culture extract of an endophytic Penicillium citrinum from Dendrobium officinale, afforded nine citrinin derivatives (1-9) and one peptide-polyketide hybrid GKK1032B (10). The structures of these compounds were determined by spectroscopic methods. The absolute configurations of 1 and 2 were determined for the first time by calculation of electronic circular dichroism (ECD) data. Among them, GKK1032B (10) showed significant cytotoxicity against human osteosarcoma cell line MG63 with an IC50 value of 3.49 µmol·L-1, and a primary mechanistic study revealed that it induced the apoptosis of MG63 cellsvia caspase pathway activation.

GKK1032B from endophytic Penicillium citrinum induces the apoptosis of human osteosarcoma MG63 cells through caspase pathway activation / 中国天然药物

Chemical investigation of the culture extract of an endophytic Penicillium citrinum from Dendrobium officinale, afforded nine citrinin derivatives (1-9) and one peptide-polyketide hybrid GKK1032B (10). The structures of these compounds were determined by spectroscopic methods. The absolute configurations of 1 and 2 were determined for the first time by calculation of electronic circular dichroism (ECD) data. Among them, GKK1032B (10) showed significant cytotoxicity against human osteosarcoma cell line MG63 with an IC50 value of 3.49 μmol·L-1, and a primary mechanistic study revealed that it induced the apoptosis of MG63 cellsvia caspase pathway activation.

Germacrane-type sesquiterpenoids with cytotoxic activity from Sigesbeckia orientalis.

Eleven new highly oxygenated germacrane-type sesquiterpenoids (1-11) and 16 known analogues (12-27) were isolated from the aerial parts of Sigesbeckia orientalis. Their structures, including absolute configurations, were determined by comprehensive spectroscopic methods especially NMR and ECD analyses. Compounds 13, 21 and 23 possessing an 8-methacryloxy group showed stronger in vitro cytotoxicity against human A549 and MDA-MB-231 cancer cell lines than other co-metabolites, with IC50 values ranging from 6.02 to 10.77 µM comparable to the positive control adriamycin.

Fabrication of Ag2O/Ag decorated ZnAl-layered double hydroxide with enhanced visible light photocatalytic activity for tetracycline degradation.

The photocatalytic performance of layered double hydroxides (LDH) is usually confined to the slow interface mobility and high recombination rate of photogenerated electron-hole pairs in material. To overcome the low photocatalytic efficiency, novel Ag2O/Ag decorated LDH (LDH-Ag2O/Ag) was successfully synthesized by depositing Ag2O on the surface of LDH and then converted to Ag° nanoparticles in the right position after heat treatment. The as-synthesized LDH-Ag2O/Ag composites were characterized by Powder X-ray diffraction (XRD), Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-visible diffuse reflectance spectra (UV-vis DRS), photoluminescence spectra (PL) and transient photocurrent (TPC) analysis. Compared with virgin LDH, the photocatalytic activities of LDH-Ag2O/Ag composites were enhanced significantly. The optimum photocatalytic efficiency of LDH-Ag10 (0.0184 min-1) was nearly 46 times higher than that of virgin LDH (0.0004 min-1). The result of active species trapping experiments indicated that •OH, h+, and •O2- have an effect on the TC degradation, where •OH played the predominant role during the photocatalytic process. The possible photocatalytic mechanisms involving the charge transfer pathway and reactive species generation during the process of TC degradation were also discussed. The improved photocatalytic activity of LDH-Ag2O/Ag could be attributed to the synergetic effect between LDH and Ag2O/Ag that extended visible light range and reduced photogenerated charge carriers recombination.

Heavy metal contamination and health risk assessment for children near a large Cu-smelter in central China.

Nonferrous metallurgy is causing significant concerns due to its emissions of heavy metals into environment, degrading environmental quality, and consequently posing high risks to human health. In this study, the concentration levels of Cadmium (Cd), Copper (Cu), Lead (Pb), and Arsenic (As) were investigated in soil, crop, well water, and fish samples collected around the Daye Copper Smelter in Hubei province, China, and the potential health risks were assessed for local children. The results showed that soils near the smelter were heavily polluted by Cd, Cu, Pb, and As, with the mean concentrations of 4.87, 195.26, 92.65, and 35.84 mg/kg, respectively, which were significantly higher than the values of soil Cd (0.18 mg/kg), Cu (32.84 mg/kg), Pb (28.46 mg/kg), and As (13.65 mg/kg) in the reference area (p < 0.001). The concentrations of Cd and As in vegetable samples collected from smelter-affected area exceeded the maximum permissible level (MPL) for food in China by 82% and 39%, respectively. The concentrations of Cd and Pb in rice grain harvested from smelter-affected area were 9.35 and 1.35 times higher than the corresponding MPL, respectively. The concentrations of Cd, As, and Cu in fish muscle from smelter-affected area exceeded the national MPL by 72%, 41%, and 24% of analyzed samples, respectively. The concentrations of Cd (p < 0.05) and As (p < 0.01) in well water were significantly higher in the smelter-affected area than those in the reference area, respectively. The health risks to local children in the smelter-affected area were 30.25 times higher than the acceptable level of 1, and most of the risks were resulted from Cd (46%), As (27%) and Pb (20%). The intake of crops was a major source (78%) to health risks for local children.

Practice and exploration of the tuition-free medical students' in rural areas of Sichuan province / 中国卫生政策研究

Objective:This paper summarizes the practical problems encountered in the implementation of the tuition-free medical students' policyin rural areas of Sichuan Province, and provides a reference for the implementation of this policy across the province. Methods :Semi-structured interviews were conducted with the principals of the orientation management policies of the health administrative departments and county level and primary health care in-stitutionsin Sichuan, and the focus group interviews were used to understand the dynamics of directed students. Results :The survey results showed that there were limited channels for students to understand the policy ; students' barren understanding of the work of grass-roots doctors ; credit and integrity files played a relatively low role in retaining medical talent students;the willingness of orientation students is higher, but there is a contradiction between applying for graduate students and retaining grassroots in rural areas ; and the relevant departments lacked a rational and efficient management mode for students. Conclusions :In order to ameliorate the construction of rural health human resources,policy administrators should place their emphasis on cultivating the sense of honor and responsibility in the rural-oriented tuition-free medical students'policy, improve the reward and punishment mechanism in policies, optimize the management and assessment process, and promote the orientation of the work among the various policy-participating departments in a more harmonious and orderly manner.

MiR-374b-5p suppresses RECK expression and promotes gastric cancer cell invasion and metastasis.

AIM: To profile expression of microRNAs (miRNAs) in gastric cancer cells and investigate the effect of miR-374b-5p on gastric cancer cell invasion and metastasis. METHODS: An miRNA microarray assay was performed to identify miRNAs differentially expressed in gastric cancer cell lines (MGC-803 and SGC-7901) compared with a normal gastric epithelial cell line. Upregulation of miR-374b-5p was newly identified and confirmed via quantitative real-time reverse transcription-PCR (qRT-PCR). MGC-803 cells were transfected with a synthesized anti-miR-374b-5p sequence or a control vector using Lipofectamine reagent, or treated with transfection reagent alone or phosphate-buffered saline as controls. Rate of transfection was verified after 48 h by qRT-PCR. Cells were then subjected to transwell migration, wound scratch and cell counting kit-8 assays. A bioinformatic analysis to identify miR-374b-5p target genes was performed using miRanda, PicTar and TargetScan software. A dual luciferase reporter assay was performed to evaluate the influence of miR-374b-5p on target gene activation, and qRT-PCR and Western blot were used to evaluate the levels of target mRNA and protein following transfection with miR-374b-5p antisense oligonucleotides. RESULTS: The microarray profiling revealed downregulation of 14 (fold change < 0.667; P < 0.05) and upregulation of 12 (fold change > 1.50; P < 0.05) miRNAs in MGC-803 and SGC-7901 cells compared with GES-1 controls. The upregulation of miR-374b-5p (fold change = 1.75 and 1.64 in MGC-803 and SGC-7901, respectively; P < 0.05) was confirmed by qRT-PCR. Compared with the control groups, the restoration of miR-374b-5p expression with anti-miR-374b-5p significantly suppressed the metastasis, invasion and proliferation of MGC-803 cells. The bioinformatic analysis predicted that the 3' untranslated region (UTR) of reversion-inducing cysteine-rich protein with Kazal motif (RECK) contains three miR-374b-5p target sequences. RECK was verified as a target gene in a dual luciferase reporter assay showing that activation of RECK 3'UTR-pmirGLO was increased by co-transfection with miR-374b-5p. Finally, transfection of miR-374b-5p antisense oligonucleotides increased mRNA and protein levels of RECK in MGC-803 cells (P < 0.05). CONCLUSION: These findings indicate that upregulation of miR-374b-5p contributes to gastric cancer cell metastasis and invasion through inhibition of RECK expression.

[Sorption of nitrobenzene to anionic surfactant modified layered double hydroxides].

Sodium dodecyl sulfate (SDS) modified MgAl layered double hydroxides (LDHs) were synthesized at different surfactant concentrations (0.5-2.0 TAEC) by the co-precipitation method. The LDH-DS samples obtained were characterized by powder X-ray diffraction and FT-IR spectroscopy. The results showed that SDS was successfully intercalated into the interlayer of the LDH, and the basal spacing was expanded from 0.80 nm to 3.98 nm. The intercalated SDS was considered consistent with a paraffin bilayers arrangement. The sorption of nitrobenzene on LDH-DS was examined, and the results showed that linear model could fit the sorption isotherms well (R2 > 0.99), which implied a partitioning sorption process. The sorption coefficient of nitrobenzene (K(d)) on LDH-DS was positively related to the DS - loading amount, but the organic carbon content normalized sorption coefficient of nitrobenzene (K(oc)) was shown to remain relatively constant. The sorption thermodynamics results showed that the sorption of nitrobenzene on LDH-DS was an endothermic process, and the increase of entropy was the driving force for the sorption process.

Differential gene and protein expression in primary gastric carcinomas and their lymph node metastases as revealed by combined cDNA microarray and tissue microarray analysis.

OBJECTIVE: To gain insight into the molecular events of lymph node metastasis of human gastric carcinoma. METHODS: The gene expression profile of five matched primary gastric carcinomas and their lymph node metastases was analyzed by complementary DNA (cDNA) microarray. Differential genes were identified in the metastatic and corresponding primary tumor pairs. Among the differentially expressed genes, carbonic anhydrase II (CAII) and insulin-like growth factor binding protein 4 (IGFBP 4) genes were detected by RT-PCR. CTTN protein expression was examined by tissue microarray. RESULTS: There was a high expression (over twofold) of 44 genes and a low expression (under twofold) of 32 genes in lymph node metastasis compared with primary gastric carcinoma, respectively. CAII mRNA was downregulated and IGFBP 4 mRNA was upregulated in paired lymph node metastases of gastric carcinomas. The overexpression of CTTN protein was related to the lymph node metastasis and the clinical stage of gastric carcinomas. CONCLUSION: This study showed that there is a low expression of genes relative to growth signal and immune response in lymph node metastases, and a high expression of genes relative to growth factor, cell cycle, cell motility and adhesion in lymph node metastases compared with primary gastric carcinomas. The expression of CTTN was related to the invasion and metastasis of gastric cancer.

[Sorption of phenol and nitrobenzene in water by CTMAB/CPAM organobentonites].

A series of cetyltrimethyl amonium bromide bentonite (C-Bt), cationic polyacrylamide bentonite (P-Bt) and composite organobentonite (C/P-Bt) were synthesized by modifying bentonite with cetyltrimethyl ammonium bromide (CTMAB) and/or cationic polyacrylamide (CPAM). The basal spacings of the obtained organobentonites were analyzed with XRD. The sorption capacities of phenol and nitrobenzene to these organobentonites from water were examined. The results showed that the basal spacing values of C/P-Bt were larger than those of C-Bt and P-Bt, which indicated a simultaneous intercalation of bentonite interlayers by CTMAB and CPAM. The sorption capacity of C/P-Bt was better than that of C-Bt. Under the same equilibrium concentration (7 045 mg/L for phenol and 409 mg/L for nitrobenzene) , the sorbed amounts of phenol and nitrobenzene on 60C/4% P-Bt were 150 and 69 mg/g, which enhanced 26% and 28% respectively comparing with those on 60C-Bt. Furthermore, the sorption capacity of 60C/4% P-Bt was better than the sum of 60C-Bt and 4% P-Bt, and the sorbed amounts of phenol and nitrobenzene enhanced 22% and 26% respectively, showing an obvious synergistic sorption effect. An explanation for these results was that the arrangement model of CTMAB within the C/P-Bt interlayers was affected by CPAM, which led to the formation of organic phase with better affinity to the organic compounds. This novel organobentonites may have wide applications in organic pollution control.

[Growth inhibition and mechanism of cetyltrimethyl ammonium chloride on Chlorella vulgaris].

Growth inhibition of cetyltrimethyl ammonium chloride (CTAC), a cationic surfactants, on Chlorella vulgaris was investigated at batch culture in laboratory. Furthermore, the corresponding mechanisms were studied by the determination of absorption capacity, Zeta potential, activity of acid phosphatase and ultrastructure of algae. Results show that the growth inhibition by CATC is enhanced with its concentration increasing from 0.1 mg/L to 1 mg/L, and 96 h-EC50 of CTAC is 0.18 mg/L. In the presence of 0.3 mg/L CTAC in 8 d, the inhibition efficiency of biomass reaches 70.7%. Meanwhile, the absorption of nitrogen and iron is inhibited 83.9% and 86.2% respectively with Zeta potential of algae cell increasing from -12.5 mV to -6.7 mV. Furthermore, the relative activity of acid phosphatase declines to 23.1% at the same time. Plasmolysis, distortion of pyrenoid and swelling of lysosome is observed in the cell. Above phenomena indicates that CTAC increases the Zeta potential of algae cell and thus inhibites the absorption of nitrogen and iron. In addition, CTAC may affect the metabolism of phosphorus and change the ultrastructure of algae cell.

[Refined mapping of the loss of heterozygosity on chromosome 1q21 in gastric carcinoma].

OBJECTIVE: To obtain allelic loss mapping and define the minimal lost region on chromosome 1q21 in gastric carcinomas, and explore role of 1q21 loss of heterozygosity (LOH) in the development and progression of gastric carcinogenesis. METHODS: Using 7 high-density microsatellite markers and PCR method, lq21 LOH was analyzed in 30 paired specimens of fresh gastric carcinoma, and the relation between 1q21 LOH and the clinicopathological features of the malignancy was tested. RESULTS: The LOH frequency on chromosome 1q21 from these gastric carcinoma tissues reached 60% (18/30). The LOH frequencies of the microsatellite markers D1S514, D1S2696, D1S498, D1S305, D1S2624, D1S2635 and D1S2702 were 13.3%, 10%, 20%, 23.3%, 33.3%, 40% and 23.3%, respectively. The minimal lost region on 1q21 LOH in the gastric carcinoma tissues was located in the region between D1S2624 and D1S2707, in the vicinity of D1S2635. No significant relations of 1q21 LOH to the patients' age, gender, location of the primary foci, clinical staging, or the tumor differentiation were noted (P>0.05), but 1q21 LOH was correlated to lymph node metastases of the malignancy (P<0.05). CONCLUSION: Higher frequency of 1q21 LOH occurs in gastric carcinoma cells, suggesting the presence of potential tumor suppressor genes closely associated with gastric carcinogenesis near the region of D1S2635.

Refined mapping of the loss of heterozygosity on chromosome 1q21 in gastric carcinoma / 南方医科大学学报

<p><b>OBJECTIVE</b>To obtain allelic loss mapping and define the minimal lost region on chromosome 1q21 in gastric carcinomas, and explore role of 1q21 loss of heterozygosity (LOH) in the development and progression of gastric carcinogenesis.</p><p><b>METHODS</b>Using 7 high-density microsatellite markers and PCR method, lq21 LOH was analyzed in 30 paired specimens of fresh gastric carcinoma, and the relation between 1q21 LOH and the clinicopathological features of the malignancy was tested.</p><p><b>RESULTS</b>The LOH frequency on chromosome 1q21 from these gastric carcinoma tissues reached 60% (18/30). The LOH frequencies of the microsatellite markers D1S514, D1S2696, D1S498, D1S305, D1S2624, D1S2635 and D1S2702 were 13.3%, 10%, 20%, 23.3%, 33.3%, 40% and 23.3%, respectively. The minimal lost region on 1q21 LOH in the gastric carcinoma tissues was located in the region between D1S2624 and D1S2707, in the vicinity of D1S2635. No significant relations of 1q21 LOH to the patients' age, gender, location of the primary foci, clinical staging, or the tumor differentiation were noted (P>0.05), but 1q21 LOH was correlated to lymph node metastases of the malignancy (P<0.05).</p><p><b>CONCLUSION</b>Higher frequency of 1q21 LOH occurs in gastric carcinoma cells, suggesting the presence of potential tumor suppressor genes closely associated with gastric carcinogenesis near the region of D1S2635.</p>

[Simultaneous sorption of aqueous phenanthrene and phosphate onto bentonites modified with AlCl3 and CTMAB].

Inorganic-organic bentonites (Al-CTMAB-Bent) were synthesized by modifying bentonites with AlCl3 and cetyltrimethyl ammonium bromide (CTMAB). Simultaneous sorption of aqueous phenanthrene and phosphate onto Al-CTMAB-Bent were examined. Removal rates of phenanthrene and phosphate from water are 96.3% and 90.2%, respectively, at their respective initial concentrations of 1 mg/L and 5 mg/L when the added amount of Al-CTMAB-Bent was 1.25 g/L. The residual turbidity of Al-CTMAB-Bent suspension decreased 81.4% comparing to that of organobentonite suspension after 1 hour settlement. Thus inorganic-organic bentonite can be used to treat wastewater containing both organic pollutants and phosphate.

Construction of hu-PBL/SCID chimeras and development of EBV-related lymphomas.

OBJECTIVE: To construct hu-PBL/SCID chimeras and to investigate the development of lymphoma and oncogenicity of the Epstein-Barr virus (EBV). METHODS: Human peripheral blood lymphocytes (PBLs) were isolated from healthy adult donors and transplanted intraperitoneally into severe combined immunodeficient (SCID) mice. Mice with hu-PBL engraftment from healthy EBV seronegative donors were injected intraperitoneally with EBV-containing supernatant from suspension culture of B95-8 cell line (active infection), whereas mice receiving lymphocytes from healthy EBV seropositive donors were not re-infected with B95-8 derived EBV (latent infection). Pathological examination and molecular analysis were performed on experimental animals and induced neoplasms. RESULTS: In the early stage of this experiment, 12 mice died of acute graft-versus-host disease, mortality was 34.3% (12/35 mice) with an average life span of 17.5 days. In 19 survival hu-PBL/SCID chimeric recipients from 12 healthy donors, tumor incidence was 84.2% (16/19 mice). The average survival time of tumor-bearing mice was 65.5 days. EBV-related neoplasms in SCID mice were nodular tumors with aggressive and fatal features. Histological morphology of tumors exhibited diffuse large cell lymphomas. Immunohistochemistry revealed that LCA (CD45) and L26 (CD20) were positive, but both PS1 (CD3) and UCHL-1 (CD45RO) were negative, and EBV products ZEBRA, LMP1, and EBNA2 were expressed in a small number of tumor cells. EB virus particles were seen in the nuclei of some tumor cells by electron microscopy, and EBV DNA could be amplified in the tumor tissues by PCR. In situ hybridization indicated that the nuclei of tumor cells contained human-specific Alu sequence. CONCLUSIONS: EBV-induced tumors were human B-cell malignant lymphomas. We obtained direct causative evidence dealing with EBV-associated tumor deriving from normal human cells.

Detection and location of Helicobacter pylori in human gastric carcinomas.

AIM: To define the infection status of Helicobacter pylori in 109 patients with gastric cancers and H pylori localization in gastric carcinoma tissues in South China. METHODS: The incidence of H pylori infection in gastric carcinomas was estimated by polymerase chain reaction (PCR), simultaneously; both morphological features and the localization of H pylori in gastric carcinomas were demonstrated by Warthin-Starry (WS) staining. The relationships between H pylori infection and the clinical-pathologic factors of gastric carcinomas were analyzed by software SPSS10.0. RESULTS: H pylori was found in 42 (39.03%) and 58 (53.21%) cases of 109 patients with gastric carcinomas by PCR and WS, respectively. H pylori infection rate detected in gastric carcinomas by WS was higher than that by PCR (chi2 = 9.735, P < 0.005 < 0.01). WS stain showed that H pylori existed in the gastric antrum mucus, mucosal gland of normal tissues adjacent to gastric carcinomas and the gland, mucus pool of cancer tissues. The positive rate of H pylori in normal tissues adjacent to carcinomas was higher than that in cancer tissues (chi2 = 15.750, P < 0.005 < 0.01). No significant differences in age, sex, site, histological types and lymph node metastasis were found between H pylori-positive gastric carcinomas and H pylori-negative cases by both methods, but there were statistically significant differences of H pylori positive rate between early and advanced stage of gastric carcinomas (chi2 = 4.548 or 5.922, P = 0.033 or 0.015 < 0.05). CONCLUSION: These results suggested that H pylori infection might play a certain role in the early stage of carcinogenesis of human gastric mucosa epithelia.

Construction of hu-PBL/SCID chimeras and development of EBV-related lymphomas / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To construct hu-PBL/SCID chimeras and to investigate the development of lymphoma and oncogenicity of the Epstein-Barr virus (EBV).</p><p><b>METHODS</b>Human peripheral blood lymphocytes (PBLs) were isolated from healthy adult donors and transplanted intraperitoneally into severe combined immunodeficient (SCID) mice. Mice with hu-PBL engraftment from healthy EBV seronegative donors were injected intraperitoneally with EBV-containing supernatant from suspension culture of B95-8 cell line (active infection), whereas mice receiving lymphocytes from healthy EBV seropositive donors were not re-infected with B95-8 derived EBV (latent infection). Pathological examination and molecular analysis were performed on experimental animals and induced neoplasms.</p><p><b>RESULTS</b>In the early stage of this experiment, 12 mice died of acute graft-versus-host disease, mortality was 34.3% (12/35 mice) with an average life span of 17.5 days. In 19 survival hu-PBL/SCID chimeric recipients from 12 healthy donors, tumor incidence was 84.2% (16/19 mice). The average survival time of tumor-bearing mice was 65.5 days. EBV-related neoplasms in SCID mice were nodular tumors with aggressive and fatal features. Histological morphology of tumors exhibited diffuse large cell lymphomas. Immunohistochemistry revealed that LCA (CD45) and L26 (CD20) were positive, but both PS1 (CD3) and UCHL-1 (CD45RO) were negative, and EBV products ZEBRA, LMP1, and EBNA2 were expressed in a small number of tumor cells. EB virus particles were seen in the nuclei of some tumor cells by electron microscopy, and EBV DNA could be amplified in the tumor tissues by PCR. In situ hybridization indicated that the nuclei of tumor cells contained human-specific Alu sequence.</p><p><b>CONCLUSIONS</b>EBV-induced tumors were human B-cell malignant lymphomas. We obtained direct causative evidence dealing with EBV-associated tumor deriving from normal human cells.</p>

[Study of the relative factors of the biological behavior of pleomorphic adenoma in parotid].

OBJECTIVE: To study the growth way of parotid pleomorphic adenoma and the relative factors. METHODS: The histological slides of 97 cases of the primary parotid pleomorphic adenoma were examined for the state of intra-capsule infiltration and extra-infiltration. The relative relationships between the infiltration state and the histological type, relative amount of various components, size and course of the tumor were analysed to investigate the growth way and relative factors. RESULTS: 1. There were more chances to develop infiltration of tumor in which the major content was epithelium. The tumor was severer with the increasing of epithelium, and decreasing of mucous content and elongation of course of the disease. 2. The limitation of the extra-envelop infiltration and budding was 0.085 - 0.210 mm, so, the boundary of partial parotidectomy should be away from the 1 cm envelop. CONCLUSION: The growth way of parotid pleomorphic adenoma is related to the histological types and characters, relative amount of various components and the course of the tumor.