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Background: The zinc finger protein 36-like (ZFP36L) family is a CCCH-type group consisting of RNA-binding proteins, i.e., ZFP36L1 and ZFP36L2, which regulate cellular mRNA through the RNA decay pathway. ZFP36L1 combats flavivirus infections through the 5′-3′ XRN1 and 3′-5′ RNA exosome decay pathways. The present study clarified the role of human ZFP36L2 in the defense response of the host against flavivirus infection. Methods: Cell lines with overexpression or knockdown of ZFP36L2 were established using lentiviral vectors carrying genes for overexpression and short-hairpin RNA targeting specific genes, respectively. A plaque assay was employed to determine the viral titer. Immunofluorescence and real-time quantitative polymerase chain reaction were used to measure the viral RNA levels. The in vitro-transcribed RNA transcript derived from a replication-dead Japanese encephalitis virus (JEV) replicon containing the renilla luciferase reporter gene (J-R2A-NS5mt) was used to assess the stability of the flavivirus RNA. An RNA immunoprecipitation assay was used to detect the protein–RNA binding ability. Confocal microscopic images were captured to analyze protein colocalization. Results: ZFP36L2 served as an innate host defender against JEV and dengue virus. ZFP36L2 inhibited flavivirus infection solely through the 5′-3′ XRN1 RNA decay pathway, whereas ZFP36L1 inhibited JEV infection via the 5′-3′ XRN1 and 3′-5′ RNA exosome RNA decay pathways. The direct binding between viral RNA and ZFP36L2 via its CCCH-type zinc finger motifs facilitated the degradation of flavivirus RNA mediated by 5′-3′ XRN1. Furthermore, ZFP36L2 was localized in processing bodies (PBs), which participate in the 5′-3′ XRN1-mediated RNA decay pathway. Nonetheless, the disruption of PBs did not affect the antiviral activity of ZFP36L2, suggesting that its localization is not essential for the function of the protein. Interestingly, the colocalization of ZFP36L2 and XRN1 with viral RNA and NS3 revealed that the antiviral activity of ZFP36L2 occurred within the replication complexes (RCs). Conclusions: In summary, ZFP36L2 bound to and degraded viral RNA through the XRN1-mediated RNA decay pathway in the RCs, thereby inhibiting flavivirus replication. These findings provide valuable insights into the diverse antiviral mechanisms of the ZFP36-like family of proteins in the innate immune response against flavivirus infection. [ABSTRACT FROM AUTHOR] more...

Background: Flavivirus causes many serious public health problems worldwide. However, licensed DENV vaccine has restrictions on its use, and there is currently no approved ZIKV vaccine. Development of a potent and safe flavivirus vaccine is urgently needed. As a previous study revealed the epitope, RCPTQGE, located on the bc loop in the E protein domain II of DENV, in this study, we rationally designed and synthesized a series of peptides based on the sequence of JEV epitope RCPTTGE and DENV/ZIKV epitope RCPTQGE. Methods: Immune sera were generated by immunization with the peptides which were synthesized by using five copies of RCPTTGE or RCPTQGE and named as JEV-NTE and DV/ZV-NTE. Immunogenicity and neutralizing abilities of JEV-NTE or DV/ZV-NTE-immune sera against flavivirus were evaluated by ELISA and neutralization tests, respectively. Protective efficacy in vivo were determined by passive transfer the immune sera into JEV-infected ICR or DENV- and ZIKV-challenged AG129 mice. In vitro and in vivo ADE assays were used to examine whether JEV-NTE or DV/ZV-NTE-immune sera would induce ADE. Results: Passive immunization with JEV-NTE-immunized sera or DV/ZV-NTE-immunized sera could increase the survival rate or prolong the survival time in JEV-challenged ICR mice and reduce the viremia levels significantly in DENV- or ZIKV-infected AG129 mice. Furthermore, neither JEV -NTE- nor DV/ZV-NTE-immune sera induced antibody-dependent enhancement (ADE) as compared with the control mAb 4G2 both in vitro and in vivo. Conclusions: We showed for the first time that novel bc loop epitope RCPTQGE located on the amino acids 73 to 79 of DENV/ZIKV E protein could elicit cross-neutralizing antibodies and reduced the viremia level in DENV- and ZIKV-challenged AG129 mice. Our results highlighted that the bc loop epitope could be a promising target for flavivirus vaccine development. [ABSTRACT FROM AUTHOR] more...

Background: Despite the high cure rate of T cell acute lymphoblastic leukemia (T-ALL), drug resistance to chemotherapy remains a significant clinical problem. Bone marrow mesenchymal stem cells (MSCs) protect leukemic cells from chemotherapy, but the underlying mechanisms are poorly understood. In this study, we aimed to uncover the mechanism of MSC-induced chemoresistance in T-ALL cells, thus providing a promising clinical therapy target. Methods: Cell viability was determined using the viability assay kit CCK-8. The mitochondrial ROS levels were detected using the fluorescent probe MitoSOXTM Red, and fluorescence intensity was measured by flow cytometry. In vitro, MSCs and Jurkat cells were cocultured. MSCs were labeled with green fluorescent protein (GFP), and Jurkat cells were labeled with the mitochondria-specific dye MitoTracker Red. Bidirectional mitochondrial transfer was detected by flow cytometry and confocal microscopy. The mechanism of mitochondria transfer was analyzed by inhibitor assays. Transcripts related to Jurkat cell/MSC adhesion in the coculture system were assessed by qRT-PCR. After treatment with a neutralizing antibody against a key adhesion molecule, mitochondria transfer from Jurkat cells to MSCs was again detected by flow cytometry and confocal microscopy. Finally, we verified our findings using human primary T-ALL cells cocultured with MSCs. Results: Chemotherapeutic drugs caused intracellular oxidative stress in Jurkat cells. Jurkat cells transfer mitochondria to MSCs but receive few mitochondria from MSCs, resulting in chemoresistance. This process of mitochondria transfer is mediated by tunneling nanotubes, which are protrusions that extend from the cell membrane. Moreover, we found that most Jurkat cells adhered to MSCs in the coculture system, which was mediated by the adhesion molecule ICAM-1. Treatment with a neutralizing antibody against ICAM-1 led to a decreased number of adhering Jurkat cells, decreased mitochondria transfer, and increased chemotherapy-induced cell death. Conclusions: We show evidence that mitochondria transfer from Jurkat cells to MSCs, which is mediated by cell adhesion, may be a potential therapeutic target for T-ALL treatment. [ABSTRACT FROM AUTHOR] more...

Background: Thyroid hemiagenesis (TH) is a rare congenital disease with absence of a thyroid lobe; most patients have no clinical symptoms. The etiology of TH remains unclear. In this paper, we describe a rare case of TH and congenital absence of the ipsilateral parathyroid gland, found during the operation, combined with the autoimmune disease Hashimoto's thyroiditis, also known as chronic lymphocytic thyroiditis. Case Presentation: A 31-year-old woman was admitted to our hospital because of a mass in the right neck. Surgical exploration validated the absence of the left lobe of the thyroid and parathyroid glands and pathological examination of the excised nodules confirmed Hashimoto's thyroiditis. Patients with TH might show accompanying absence of the ipsilateral parathyroid gland. The case described here, in which TH was combined with Hashimoto's thyroiditis, is rare in the medical literature. The operation should be ended at once if Hashimoto's thyroiditis is diagnosed during surgery. Conclusions: Absence of thyroid lobe may accompany with a congenital absence of the ipsilateral parathyroid gland and Hashimoto's thyroiditis. Fine needle aspiration is essential to diagnosis and decision-making of the treatment. [ABSTRACT FROM AUTHOR] more...

Background: The intraocular pressure (IOP) is maintained through a dynamic equilibrium between the production and drainage of aqueous humor. Elevation of intraocular pressure is mainly caused by the blocking of aqueous humor outflow pathway. Therefore, it is particularly important to study the structure of drainage pathway and the effect of ocular hypertension at the process of aqueous humor outflow.Methods: Conventional drainage pathway of aqueous humor, including trabecular meshwork (TM), Schlemm's canal (SC) and aqueous vein, were imaged by using trans-scleral imaging method with lateral resolution of 2 μm. For quantitative assessment, the morphological parameters of the TM were measured with different IOP levels via a combination of measurements and simulations.Results: Images of the TM and the adjacent tissues were obtained. The porosity of TM with normal intraocular pressure varies from 0.63 to 0.74 as the depth increases, while in high IOP it is changed from 0.44 to 0.59. The diameter of aqueous vein varies from 32 to 43 μm, and is smaller than that of SC, which varies from 48 to 64.67 μm.Conclusions: Our research provides a non-contact method to visualize the microstructure of tissue for clinical examination associated with the blocking of the outflow pathway of aqueous humor in humans. The three-dimensional (3D) microstructures of limbus and the results of finite element modeling analysis of the TM model will serve for the future evaluation of new glaucoma surgical techniques. [ABSTRACT FROM AUTHOR] more...

Background: Zuo-Jin-Wan (ZJW), a traditional Chinese medicine formula, has been identified to be effective against drug resistance in cancer. In the present study, we investigated the effect of ZJW on acquired oxaliplatin-resistant and the PI3K/Akt/NF-κB pathway in vitro. Methods: We tested the dose--response relationship of ZJW on reversing drug-resistance by CCK-8 assay and flow cytometry analysis in vitro. The protein expression of P-gp, MRP-2, LRP, and ABCB1 mRNA expression level were evaluated by Western blot and quantitative RT-PCR. The activities of PI3K/Akt/NF-κB pathway were also examined with or without ZJW, including Akt, IκB, p65 and their phosphorylation expression. Results: We found that ZJW significantly enhanced the sensitivity of chemotherapeutic drugs and increased oxaliplatin (L-OHP)-induced cell apoptosis in a time- and dose-dependent manner. Moreover, both ZJW and a PI3K specific inhibitor (LY294002) suppressed phosphorylation of Akt (Ser473) and NF-κB, which is necessary in the activation of the PI3K/Akt/NF-κB pathway. The effect of ZJW in reversing drug-resistance and suppressing phosphorylation of Akt (Ser473) and NF-κB were weakened after treatment with a PI3K/Akt activator in HCT116/L-OHP cells. Conclusions: Our study has provided the first direct evidence that ZJW reverses drug-resistance in human colorectal cancer by blocking the PI3K/Akt/NF-κB signaling pathway, and could be considered as a useful drug for cancer therapy. [ABSTRACT FROM AUTHOR] more...

Background As a secreted protein, serum trefoil factor 3 (TFF3) has been reported to be a biomarker of several malignancies. We further investigated whether TFF3 can be applied as a biomarker for and predictor of responses to chemotherapy in gastrointestinal cancer. Methods Serum and urine samples were collected from 90 patients with gastric cancer, 128 patients with colorectal cancer and 91 healthy individuals. Serum and urine TFF3 levels were measured using an ELISA. Results Serum and urine TFF3 levels were significantly higher in the patients with gastric and colorectal cancer compared with the healthy individuals (P < 0.05). Higher serum levels of TFF3 were significantly correlated with distant metastasis and an advanced stage in the two types of cancer (P < 0.05). Age and the number of lymph node metastases were significantly correlated with serum TFF3 levels in colorectal cancer, and decreased serum TFF3 levels were significantly correlated with responses to chemotherapy in both the gastric and the colorectal cancer partial response (PR) groups. A combination of serum and urine data did not significantly improve the detection of either cancer, although urine levels have shown a significant negative relationship with the glomerular filtration rate (GFR). Conclusions Our data indicate that TFF3 may be an effective biomarker of tumor stage and the presence of distant metastasis, and may be a pharmacodynamic marker of response to chemotherapy in gastrointestinal cancer. [ABSTRACT FROM AUTHOR] more...

Background Childhood undernutrition adversely impacts child health and is one of China's largest health burdens. However, there is limited information on the current rate of childhood undernutrition in rural Western China. The purpose of this study was to investigate the prevalence of childhood undernutrition and explore its association with socio-economic characteristics in Western China. Methods A total of 13,532 children of 0 ~ 36 months of age were recruited as subjects from 45 counties and 10 provinces in Western China with a 3-stage probability proportion to size sampling. The composite index of anthropometric failure (CIAF) was used to assess the childhood undernutrition. The association between socio-economic characteristics and childhood undernutrition was analyzed using a two-level logistic regression. Results Based on CIAF, the prevalence of undernutrition among children under three years of age in rural Western China in 2005 was 21.7%. The two-level logistic analysis presented a large difference in undernutrition among the 10 provinces with the highest odds ratio in Guizhou (OR: 2.15, 95%CI: 1.50, 3.08). Older children had a higher prevalence of undernutrition. As compared to girls, boys were more likely to be undernourished (OR 1.27, 95%CI: 1.16, 1.39). The likelihood of undernutrition was lower in subjects of Han ethnicity as opposed to subjects of minority ethnicities (OR 0.77, 95%CI: 0.65, 0.90). In addition, the education levels of the mother as well as wealth index were both negatively associated with childhood undernutrition. Conclusions Childhood undernutrition still remains a large health challenge in rural Western China. This study has important policy implications for the Chinese government to improve childhood undernutrition in the surveyed areas. [ABSTRACT FROM AUTHOR] more...

Background: There are multiple adverse effects of anemia on human function, particularly on women. However, few researches are conducted on women anemia in rural Western China. This study mainly aims to investigate the levels and associated factors of maternal anemia between 2001 and 2005 in this region. Methods: 6172 and 5372 mothers with children under three years old were selected from 8 provinces in 2001 and from 9 provinces in 2005 respectively in Western China by means of a multi-stage probability proportion to size sampling method (PPS). The blood samples were tested and related socio-demographic information was obtained through questionnaires. A two-level logistic regression model was employed to identify the determinants and provincial variations of women anemia in 2001 and 2005. Results: The results indicated that the crude prevalence of women anemia in 2005 was higher than the rate in 2001(45.7% vs 33.6%). Based on the nationwide census data in 2000, the age-standardized prevalence of women anemia in the study were obtained as 38.0% in 2001 and 50.0% in 2005 respectively. Two-level logistic model analysis showed that compared to the average, women were more likely to be anemic in Guangxi and Qinghai in 2001 as well as in Chongqing and Qinghai in 2005; that women from Minority groups had higher odds of anemia in contrast with Han; that women with higher parity, longer breastfeeding duration and higher socioeconomic level had a lower rate of anemia, while age of women was positively associated with anemia. The positive correlation between women anemia and altitude was also observed. Conclusions: The study demonstrated that the burden of maternal anemia in rural Western China increased considerably between 2001 and 2005. The Chinese government should conduct integrated interventions on anemia of mothers in this region. [ABSTRACT FROM AUTHOR] more...

Background: Serine-arginine rich splicing factor 2 (SRSF2) is a protein known for its role in RNA splicing and genome stability. It has been recently discovered that SRSF2, along with other splicing regulators, is frequently mutated in patients with myelodysplastic syndrome (MDS). The most common MDS mutations in SRSF2 occur at proline 95; the mutant proteins are shown to have different RNA binding preferences, which may contribute to splicing changes detected in mutant cells. However, the influence of these SRSF2 MDS-associated mutations on specific splicing events remains poorly understood., Results: A tetracycline-inducible TF-1 erythroleukemia cell line was transduced with retroviruses to create cell lines expressing HA-tagged wildtype SRSF2, SRSF2 with proline 95 point mutations found in MDS, or SRSF2 with a deletion of one of the four major domains of the protein. Effects of these mutants on apoptosis and specific alternative splicing events were evaluated. Cells were also treated with DNA damaging drugs for comparison. MDS-related P95 point mutants of SRSF2 were expressed and phosphorylated at similar levels as wildtype SRSF2. However, cells expressing mutant SRSF2 exhibited higher levels of apoptosis than cells expressing wildtype SRSF2. Regarding alternative splicing events, in nearly all examined cases, SRSF2 P95 mutants acted in a similar fashion as the wildtype SRSF2. However, cells expressing SRSF2 P95 mutants had a percent increase in the C5 spliced isoform of cell division cycle 25C (CDC25C). The same alternative splicing of CDC25C was detected by treating cells with DNA damaging drugs, such as cisplatin, camptothecin, and trichostatin A at appropriate dosage. However, unlike DNA damaging drugs, SRSF2 P95 mutants did not activate the Ataxia telangiectasia mutated (ATM) pathway., Conclusion: SRSF2 P95 mutants lead to alternative splicing of CDC25C in a manner that is not dependent on the DNA damage response. more...

Background: Mitochondria play important roles in providing metabolic energy and key metabolites for synthesis of cellular building blocks. Mitochondria have additional functions in other cellular processes, including programmed cell death and aging. A previous study revealed Drosophila mitochondrial topoisomerase III alpha (Top3α) contributes to the maintenance of the mitochondrial genome and male germ-line stem cells. However, the involvement of mitochondrial Top3α in the mitochondrion-mediated aging process remains unclear. In this study, the M1L flies, in which Top3α protein lacks the mitochondrial import sequence and is thus present in cell nuclei but not in mitochondria, is used as a model system to examine the role of mitochondrial Top3α in the aging of fruit flies., Results: Here, we reported that M1L flies exhibit mitochondrial defects which affect the aging process. First, we observed that M1L flies have a shorter life span, which was correlated with a significant reduction in the mitochondrial DNA copy number, the mitochondrial membrane potential, and ATP content compared with those of both wildtype and transgene-rescued flies of the same age. Second, we performed a mobility assay and electron microscopic analysis to demonstrate that the locomotion defect and mitophagy of M1L flies were enhanced with age, as compared with the controls. Finally, we showed that the correlation between the mtDNA deletion level and aging in M1L flies resembles what was reported in mammalian systems., Conclusions: The results reported here demonstrate that mitochondrial Top3α ablation results in mitochondrial genome instability and its dysfunction, thereby accelerating the aging process. more...

Viral infections are important causes of morbidity and mortality after allogeneic stem cell hematopoietic transplantation (allo-HSCT). Although most viral infections present with asymptomatic or subclinical manifestations, viruses may result in fatal complications in severe immunocompromised recipients. Reactivation of latent viruses, such as herpesviruses, is frequent during the immunosuppression that occurs with allo-HSCT. Viruses acquired from community, such as the respiratory and gastrointestinal viruses, are also important pathogens of post-transplant viral diseases. Currently, molecular diagnostic methods have replaced or supplemented traditional methods, such as viral culture and antigen detection, in diagnosis of viral infections. The utilization of polymerase chain reaction facilitates the early diagnosis. In view of lacking efficacious agents for treatment of viral diseases, prevention of viral infections is extremely valuable. Application of prophylactic strategies including preemptive therapy reduces viral infections and diseases. Adoptive cellular therapy for restoring virus-specific immunity is a promising method in the treatment of viral diseases. more...