Fever with thrombocytopenia associated with a novel bunyavirus in China.

BACKGROUND: Heightened surveillance of acute febrile illness in China since 2009 has led to the identification of a severe fever with thrombocytopenia syndrome (SFTS) with an unknown cause. Infection with Anaplasma phagocytophilum has been suggested as a cause, but the pathogen has not been detected in most patients on laboratory testing. METHODS: We obtained blood samples from patients with the case definition of SFTS in six provinces in China. The blood samples were used to isolate the causal pathogen by inoculation of cell culture and for detection of viral RNA on polymerase-chain-reaction assay. The pathogen was characterized on electron microscopy and nucleic acid sequencing. We used enzyme-linked immunosorbent assay, indirect immunofluorescence assay, and neutralization testing to analyze the level of virus-specific antibody in patients' serum samples. RESULTS: We isolated a novel virus, designated SFTS bunyavirus, from patients who presented with fever, thrombocytopenia, leukocytopenia, and multiorgan dysfunction. RNA sequence analysis revealed that the virus was a newly identified member of the genus phlebovirus in the Bunyaviridae family. Electron-microscopical examination revealed virions with the morphologic characteristics of a bunyavirus. The presence of the virus was confirmed in 171 patients with SFTS from six provinces by detection of viral RNA, specific antibodies to the virus in blood, or both. Serologic assays showed a virus-specific immune response in all 35 pairs of serum samples collected from patients during the acute and convalescent phases of the illness. CONCLUSIONS: A novel phlebovirus was identified in patients with a life-threatening illness associated with fever and thrombocytopenia in China. (Funded by the China Mega-Project for Infectious Diseases and others.).

Lyme Borreliosis-associated Risk Factors in Residents of Beijing Suburbs: a Preliminary Case-control Study.

A population-based case-control study was conducted to evaluate the relative factors in the environments, agricultural works, outdoor activities, and the effectiveness of Lyme borreliosis (LB)- associated personal protective measures in Beijing. Thirty-four cases and 272 controls were personally interviewed by well-trained interviewers. Venous blood samples were taken from each subject. Sowing or harvesting in summer (OR=2.571, 95% CI: 1.109-5.962), living in house with weeding in the yard (OR=2.247, 95% CI: 1.062-4.755), and residence at the plain area (OR=2.630, 95% CI: 1.050-6.588) were the independent relative factors for seropositive LB. Wearing long pants and clothes with cuffs was the only protective behavior against tick bite (OR=0.186, 95% CI: 0.041-0.846). The findings showed that local farmers were easily infected with LB and almost no protective measure was taken against LB infection. Infection with LB was easier in residents of plain regions. Pets raising and outdoor activities were not the risk factors for infection with LB. Further studies are needed to fully understand the risk of infection with LB in China.

Bone marrow-derived mesenchymal stem cell-derived exosome-loaded miR-129-5p targets high-mobility group box 1 attenuates neurological-impairment after diabetic cerebral hemorrhage.

BACKGROUND: Diabetic intracerebral hemorrhage (ICH) is a serious complication of diabetes. The role and mechanism of bone marrow mesenchymal stem cell (BMSC)-derived exosomes (BMSC-exo) in neuroinflammation post-ICH in patients with diabetes are unknown. In this study, we investigated the regulation of BMSC-exo on hyperglycemia-induced neuroinflammation. AIM: To study the mechanism of BMSC-exo on nerve function damage after diabetes complicated with cerebral hemorrhage. METHODS: BMSC-exo were isolated from mouse BMSC media. This was followed by transfection with microRNA-129-5p (miR-129-5p). BMSC-exo or miR-129-5p-overexpressing BMSC-exo were intravitreally injected into a diabetes mouse model with ICH for in vivo analyses and were cocultured with high glucose-affected BV2 cells for in vitro analyses. The dual luciferase test and RNA immunoprecipitation test verified the targeted binding relationship between miR-129-5p and high-mobility group box 1 (HMGB1). Quantitative polymerase chain reaction, western blotting, and enzyme-linked immunosorbent assay were conducted to assess the levels of some inflammation factors, such as HMGB1, interleukin 6, interleukin 1ß, toll-like receptor 4, and tumor necrosis factor α. Brain water content, neural function deficit score, and Evans blue were used to measure the neural function of mice. RESULTS: Our findings indicated that BMSC-exo can promote neuroinflammation and functional recovery. MicroRNA chip analysis of BMSC-exo identified miR-129-5p as the specific microRNA with a protective role in neuroinflammation. Overexpression of miR-129-5p in BMSC-exo reduced the inflammatory response and neurological impairment in comorbid diabetes and ICH cases. Furthermore, we found that miR-129-5p had a targeted binding relationship with HMGB1 mRNA. CONCLUSION: We demonstrated that BMSC-exo can reduce the inflammatory response after ICH with diabetes, thereby improving the neurological function of the brain.

[Expression and function of vascular endothelial growth factor and angiopoietins in rat brain after cerebral ischemia].

OBJECTIVE: To examine the temporal and spatial expression of vascular endothelial growth factor (VEGF) and angiopoietins (Ang) in rat brain after cerebral ischemia, and to elucidate the roles they played in angiogenesis and vascular permeability. METHODS: Rats were subjected to either middle cerebral artery occlusion (MCAO) or sham operation. Reverse transcriptase-polymerase chain reaction, Western blotting, and immunohistochemistry were used to detect the expression of VEGF, Ang-1 and Ang-2 at different time points after ischemia. CD31 was used to label endothelial cells after MCAO. Vascular permeability was determined by Evans blue. RESULTS: VEGF was markedly increased at 2 h, had an initial peak at 12 h (0.7249 ± 0.1933, P < 0.01), and a second peak at 7 days (0.5264 ± 0.1519, P < 0.01). Ang-2 mRNA and protein significantly increased after MCAO, both of them peaked at 12 h (0.6747 ± 0.2416, P < 0.01; 1.1197 ± 0.1780, P < 0.01). In contrast, Ang-1 mRNA and protein gradually decreased after MCAO, respectively reaching a minimum at 3 d (0.3220 ± 0.1427, P < 0.01) and 1 d (0.1298 ± 0.0293, P < 0.01). Changes in the expression of these factors correlated with the progress of angiogenesis and vascular permeability. Evans blue test revealed that the vascular permeability gradually increased, and peaked at day 1 after ischemia [(6.219 ± 0.887) µg/g, P < 0.01]. CONCLUSION: Dynamic temporal changes in VEGF, Ang-1 and Ang-2 expression stimulate the cerebral angiogenesis after focal cerebral ischemia.

Down-regulation of tumor suppressor gene FEZ1/LZTS1 in breast carcinoma involves promoter methylation and associates with metastasis.

FEZ1/LZTS1 is a tumor suppressor gene located in chromosomal band 8p22, and methylation has been identified as a mechanism for its loss of function in tumors. Chromosomal deletion at 8p22 is also frequent in breast cancer. We therefore examined whether LZTS1 plays a role in breast cancer. We analyzed expression of LZTS1 at both the RNA and protein levels, and promoter methylation in a number of primary tumors and cell lines from breast cancer. We also examined the association between LZTS1 expression and different clinicopathological parameters of breast cancer. We found that the expression of LZTS1 mRNA was reduced in 25 of 50 (50%) primary tumors and 29 of 30 (97%) breast cancer cell lines. Immunohistochemical staining showed that LZTS1 protein was absent or down-regulated in 72 (72%) of 100 primary breast carcinomas. Reduced expression of LZTS1 at either the RNA or protein level was significantly correlated with lymph node metastases (P < 0.05). DNA methylation analysis revealed that the LZTS1 gene was frequently methylated in both cell lines and primary tumors from breast cancer, and the extent of DNA methylation was correlated with reduced expression of the gene. These findings suggest that LZTS1 plays a role in the development and progression of breast cancer at least through promoter methylation-mediated transcriptional downregulation.

HIV prevalence in suspected Ebola cases during the 2014-2016 Ebola epidemic in Sierra Leone.

BACKGROUND: The 2014-2016 Ebola virus epidemic in West Africa was the largest outbreak of Ebola virus disease (EVD) in history. Clarifying the influence of other prevalent diseases such as human immunodeficiency virus infection and acquired immune deficiency syndrome (HIV/AIDS) will help improve treatment and supportive care of patients with EVD. CASE PRESENTATION: We examined HIV and hepatitis C virus (HCV) antibody prevalence among suspected EVD cases from the Sierra Leone-China Friendship Biological Safety Laboratory during the epidemic in Sierra Leone. HIV and HCV antibodies were tested in 678 EVD-negative samples by enzyme-linked immunosorbent assay. A high HIV prevalence (17.6%) and low HCV prevalence (0.22%) were observed among the suspected cases. Notably, we found decreased HIV positive rates among the suspected cases over the course of the epidemic. This suggests a potentially beneficial effect of an improved public health system after assistance from the World Health Organization and other international aid organizations. CONCLUSIONS: This EVD epidemic had a considerable impact on the public health system and influenced the prevalence of HIV found among suspected cases in Sierra Leone, but also provided an opportunity to establish a better surveillance network for infectious diseases.

Breast carcinoma with micropapillary features: clinicopathologic study and long-term follow-up of 100 cases.

To study the clinicopathologic characteristics and prognosis of invasive micropapillary carcinoma of breast (IMPC), 100 cases of invasive breast carcinoma with an IMPC component were reviewed. Compared with invasive ductal carcinoma, not otherwise specified, with similar histologic grades, carcinomas with IMPC were larger sized, had a higher lymph node metastasis rate with more nodes involved per case, and exhibited increased lymphovascular invasion. The presence of IMPC strongly correlated with the more aggressive behavior. No significant association was established between the proportion of the IMPC component and overall tumor size, histologic grade, lymph node metastasis rate, and distant metastasis, but a trend was noted. Long-term follow-up demonstrated a poorer 5-year and 10-year survival rate for patients with breast carcinoma containing an IMPC component. Breast carcinomas with micropapillary features are more aggressive tumors with a poorer prognosis. This specific structure should be carefully evaluated in the surgical pathology examination of breast carcinoma specimens.

[Diagnosis and prognosis study of breast carcinoma with micropapillary component].

OBJECTIVE: To study the diagnostic criteria, clinicopathologic characteristics and prognosis of invasive micropapillary carcinoma (IMPC) of breast. METHODS: All cases of breast carcinoma diagnosed during the period from 1989 to 2001 were retrospectively reviewed. One hundred examples with IMPC component, according to the 2003 World Health Organization classification of breast tumors, were identified. The clinicopathologic features and follow-up data of these cases were analyzed. RESULTS: Amongst the 100 cases of IMPC studied, 69% (69/100) had evidence of lymphovascular invasion. The incidence of regional lymph node metastasis was 84.8% (84/99). Follow-up information was available in 98 patients (mean of follow-up duration = 60.1 months). Eleven patients (11.2%) had local recurrence within a mean of 26.4 months after the operation, while 38 patients (38.8%) had distant metastases within a mean of 36.0 months. Thirty-six patients (36.7%) died of the disease. The overall 5-year survival rate was 59% and the 10-year survival rate was 48%. Univariate and multivariate analysis showed that the prognosis of patients was adversely affected by the presence of lymphovascular invasion and family history of breast cancer. On the other hand, tamoxifen therapy and adjuvant chemotherapy improved survival. CONCLUSIONS: Breast carcinoma with IMPC component is associated with poor prognosis, despites the relative proportion of this architectural pattern. The overall prognosis is related to the presence of lymphovascular invasion and family history of breast cancer. Hormonal therapy and individualized chemotherapy can improve the survival rate.

[Targeted down-regulation of p53 gene expression by individual antisense RNA in vitro].

OBJECTIVE: To investigate the effect of specific blockage of mutant p53 gene by individualized antisense RNA in vitro. METHODS: Mutation status of p53 in human breast cancer cell lines was determined by immunocytochemical staining, PCR-SSCP and sequencing. Single strand antisense transcription system targeting specific p53 mutation site (mt-p53) was constructed, and corresponding antisense RNA was prepared. The hybridization of antisense RNA with its corresponding mt-p53 gene was confirmed by in-situ hybridization. Human breast cancer cells were transfected with antisense RNA by cationic liposome-mediated method. Time course of effects of antisense RNA was investigated by immunocytochemical staining and cell growth inhibiting assay. Expression of mt-p53 protein was examined by Western blot. Cell proliferation was evaluated by MTT assay and cell cycle distribution was determined by flow cytometry (FCM). Apoptosis was determined by TUNEL assay. RESULTS: Mutation of p53 exon 8 was found in MDA-MB-231 cells and antisense transcription system (pGEM3zf (+/-) p53exon8) was then constructed successfully. In transfected MDA-MB-231 cells, hybridization signals were observed in cytoplasm. Fourth-eight hours after transfection, the antisense RNA (ASp53exon8'RNA) had a significant retarding effect on p53 related proliferation inhibition, along with a decrease of p53 protein expression. CONCLUSIONS: ASp53exon8'RNA specifically blocks mt-p53 gene expression, resulting in an inhibition of MDA-MB-231 cell proliferation. Such an approach may be used as a therapeutic option against human malignancy.

[Establishment of minireplicon system for severe fever with thrombocytopenia syndrome bunyavirus].

Severe fever with thrombocytopenia syndrome bunyavirus is a newly emerging virus in China, enveloped with a tripartite, single-stranded RNA genome of negative polarity. The regulatory elements for viral transcription and replication, as well as encapsidation and packaging signals, are thought to be located within these noncoding regions (NCRs). The terminal nucleotides are genus specific and highly conserved. The function of the remaining nucleotides of the NCRs is still not well understood. In this study, we developed the plasmid-driven RNA polymerase I minireplicon system for SFTSV firstly, using reporter genes GFP and luciferase. The function of the noncoding regions of the three Bunyaviridae RNA segments (L, M, S) in transcription was analyzed. Reporter genes are successfully expressed in SFTSV minireplicon system. Our results suggest that the NCRs of SFTSV from all three segments contain the necessary signals to initiate transcription. Quantitative detection of the luciferase expression level shows that promoter activity in the three segments is different.

Ehrlichiosis and zoonotic anaplasmosis in suburban areas of Beijing, China.

In 2006, an unusual nosocomial outbreak of anaplasmosis occurred in Anhui Province, China. To follow these emerging tickborne-rickettsioses, a larger survey of Ehrlichia chaffeensis and Anaplasma phagocytophilum seroprevalence among farm worker populations, and the divergence of the partial 16S rRNA gene sequences of A. phagocytophilum among domestic animals, were conducted in Yanqing, Miyun, and Tongzhou Counties in Beijing from March to April, 2009. Blood samples from 562 farmers, 90 goats, 73 cattle, and 2 dogs were collected. IgG antibodies against E. chaffeensis and A. phagocytophilum were assayed by micro-indirect immunofluorescence assay (IFA). Partial fragments of 16S rRNA genes of A. phagocytophilum were amplified from blood DNA from domestic animals and their sequences analyzed. The total E. chaffeensis and A. phagocytophilum seroprevalence among the farm worker population was 16.4% and 14.1%, respectively. For domestic animals, the seropositive rates of A. phagocytophilum for goats, cattle, and dogs, were 2.3%, 0%, and 0%, respectively. The PCR-positive rates for A. phagocytophilum in goats and cattle were 48.9% and 23.9%, respectively. Three dominant genetic groups of Chinese A. phagocytophilum isolates were determined for goats and cattle, and these isolate varieties were broadly identified in China, Japan, and Korea. The prevalence of E. chaffeensis and A. phagocytophilum among farmers and domestic animals in Beijing rural areas was also demonstrated. The diagnoses and differential diagnoses of these emerging infectious diseases should be emphasized in clinics, and further ecological investigation of E. chaffeensis and A. phagocytophilum vectors and hosts is needed.

[Investigation on Ehrlichia chaffeensis and Anaplasma phagocytophilum infection among farmers and domestic animals in rural areas of Beijing, China].

OBJECTIVE: To investigate the status of Ehrlichia (E.) chaffeensis and Anaplasma (A.) phagocytophilum infection among farming populations and domestic animals in the rural area of Beijing, China. METHODS: Blood samples from 562 farmers and 163 blood samples including 90 goats, 71 ox and 2 dogs, were collected. Specificity of IgG antibodies against E. chaffeensis and A. phagocytophilum were tested by micro-indirect immunofluorescent assay (mIFA). 16S rRNA genes of A. phagocytophilum were amplified from the domestic animal blood samples and products were sequenced and analyzed by nested PCR. RESULTS: The positive rates of E. chaffeensis and A. phagocytophilum antibody were 16.5% and 14.0% respectively for farmers. The total positive rates of A. phagocytophilum were 2.3% and 0 for both goats and oxen respectively. No antibody was found for the 2 tested dogs. The PCR positive rates were 48.9% and 23.9% for goats and oxen respectively. Three dominant varieties of A. phagocytophilum were demonstrated in goats and oxen. CONCLUSION: The prevalence rates of E. chaffeensis and A. phagocytophilum were identified in the rural areas of Beijing.

Correlation of Notch1 expression and activation to cisplatin-sensitivity of head and neck squamous cell carcinoma.

BACKGROUND AND OBJECTIVE: Notch1 belongs to the Notch family of transmembrane receptors and plays an important role in tumor cell proliferation and apoptosis. Notch1 affects chemosensitivity of tumors. However, its correlation to cisplatin (DDP)-sensitivity of head and neck squamous cell carcinoma is unclear. This study was to identify the expression of Notch1 in head and neck squamous cell carcinoma, and investigate its influence on the DDP-sensitivity. METHODS: Twenty-five fresh specimens of head and neck squamous cell carcinoma were subjected to primary cell culture. DDP-sensitivity of tumor cells was detected using collagen gel droplet embedded culture-drug sensitivity test (CD-DST). The expression of Notch1 in head and neck squamous cell carcinoma, normal squamous epithelium, and tongue squamous cell carcinoma Tb3.1 cells was detected by immunohistochemistry or immuocytochemistry. Tb3.1 cells were divided into four groups, and received treatment of DMSO, DAPT, DMSO plus DDP, DAPT plus DDP, respectively. The absorbance of the four groups was detected by CD-DST to evaluate DDP-sensitivity. RESULTS: The positive rate of Notch1 was significantly higher in head and neck squamous cell carcinoma than in normal squamous epithelium (100% vs. 35%, p < 0.001), and it was negatively correlated to DDP-sensitivity (r = -0.705, p < 0.01). There was no difference in absorbance between DMSO group and DAPT group (155.4 +/- 2.3 vs. 154.7 +/- 1.2, p > 0.05), while the absorbance was significantly higher in DMSO plus DDP group than in DAPT plus DDP (33.9 +/- 1.3 vs. 26.6 +/- 1.1, p < 0.05). CONCLUSIONS: Notch1 expression is negatively correlated to DDP-sensitivity of head and neck squamous cell carcinoma, and could be used to predict DDP-sensitivity. DAPT can enhance DDP-sensitivity of Tb3.1 cells via blocking Notch1 signaling.

Defective beta1-integrins expression in arsenical keratosis and arsenic-treated cultured human keratinocytes.

BACKGROUND: beta1-integrins, which localize to the basolateral surface of basal keratinocytes, are important in the differentiation control and proliferation of the epidermis. Many cutaneous diseases with perturbed differentiation, including arsenical keratosis, show altered patterns of integrin distribution and expression. Arsenic may induce arsenical keratosis through the differentiation and apoptosis aberration by integrins. The purpose of this study is to investigate the role of integrin and arsenic in the pathogenesis of arsenical keratosis. METHODS: Twenty-five specimens obtained from 25 patients with arsenical keratosis disease were studied. Immunohistochemistry staining to beta1, alpha2beta1, or alpha3beta1 integrins was performed in arsenical keratosis and clinically normal perilesional skin. Western blotting was used to assess the expression of integrin beta1 and focal adhesion kinase (FAK) in arsenic-treated cultured keratinocytes. RESULTS: A decreased expression of beta1, alpha2beta1, or alpha3beta1 integrins was demonstrated in arsenical keratosis and clinical normal perilesional skin in a large proportion of arsenical keratosis cases studied. The expressions of integrin beta1 and FAK were both decreased in arsenic-treated keratinocytes. CONCLUSIONS: Our results suggest that arsenic induces abnormal differentiation in arsenical keratosis via the effects of integrin expression in keratinocytes.

[Using recombinant antigens of Hantavirus to study the kinetics of serum IgA, IgG, IgM antibodies in the acute-phase of hemorrhagic fever renal syndrome].

BACKGROUND: To observe the features of serum specific IgA, IgG, IgM antibodies in the acute phase of hemorrhagic fever renal syndrome (HFRS). METHODS: The nucleocapsid (NP) protein and glycoproteins (GP) of Hantavirus were expressed by recombinant baculovirus, and used as ELISA antigens to test 61 serial sera of 14 acute phase HFRS patients. RESULTS: Seoul like virus RNA were detected from 11 of 14 patients. An early and strong IgA, IgG and IgM antibody response to recombinant NP (rNP) was observed in almost all HFRS cases. The titers of antibody to rNP was apparently higher than that to Rgp. In the early stage, titer of IgG antibody elevated most drastically among all the three classes of antibodies to rNP, followed by IgM and IgA antibody responses. The elevation trend of IgM and IgA antibodies to rNP stayed nearly at the same level, but the IgA titers to rNP were apparently higher than that of IgM. Among the antibodies to rGP, IgA changed distinctly greater than IgG. The elevation trend of IgM could be found during first week after the onset, and the titers dropped gradually after the second week. IgM antibodies of one case who was viral RNA positive were not detected at early stage, but IgA titers were high. The only severe case of the 14 patients kept the lower IgA, IgG and IgM during the whole acute phase. CONCLUSION: HFRS patients kept an early and strong humoral response to NP and GPs in acute phase of HFRS.IgA could be used together with IgM to improve the diagnostic accuracy.