Detection, sequence analysis, and antibody prevalence of porcine deltacoronavirus in Taiwan.

Porcine deltacoronavirus (PDCoV) was initially documented in Hong Kong and later in the United States, South Korea, and Thailand. To investigate if PDCoV is also present in Taiwan, three swine coronaviruses-PDCoV, porcine epidemic diarrhea virus (PEDV), and transmissible gastroenteritis coronavirus (TGEV)-were tested using real-time reverse transcription polymerase chain reaction (rRT-PCR) in 172 rectal swab samples from piglets exhibiting diarrhea between January 2016 and May 2017 on 68 pig farms in Taiwan. The rRT-PCR results were positive for PDCoV (29/172, 16.9%), PEDV (36/172, 20.9%), TGEV (2/172, 1.2%), and coinfections (16/172, 9.3%). After cloning and sequencing, PDCoV nucleocapsid genes were analyzed. Phylogeny results indicated that the nucleotide sequences of all isolates were like those reported in other countries. To further trace PDCoV in the period of 2011 to 2015, an enzyme-linked immunosorbent assay (ELISA) was used to detect antibodies against PDCoV. The results showed that 279 of 1,039 (26.9%) sera were positive for the PDCoV nucleocapsid protein, implying that PDCoV might have existed in Taiwan before 2011.

[Diurnal activity pattern and seasonal variations of captive Papio hamadryas.] / åœˆå »é˜¿æ‹‰ä¼¯ç‹’ç‹’æ—¥æ´»åŠ¨æ—¶é—´æ ¼å±€åŠå­£èŠ‚å·®å¼‚.

Activity rhythms and time budgets are two important components of ecological influences on animal individual behaviors. We collected data on activity pattern using instantaneous scan sampling on captive hamadryas baboons (Papio hamadryas) in Hangzhou Wild Animal Zoo in Zhejiang, China from November 2012 to October 2013. The results showed that: 1) In the activity time allocation, the main activities (frequency percentage was more than or equal to 5%) included resting (42.5%), traveling (16.2%), playing (10.0%), feeding (9.8%), grooming (9.4%) and watching (7.3%), and the secondary activities (frequency percentage is lower than 5%) only accounted for a total of 4.8%. 2) Due to increasing in the feeding and watching time, and decreasing in the playing and grooming time in winter, their time budgets showed significant seasonal variation, but the resting and swimming time had no significant difference between the cold season and the warm season. 3) The diurnal activity rhythms of P. hamadryas showed two feeding peaks of morning and afternoon, and as the temperature gradually turned cold, feeding activity gradually increased with three feeding peaks, which might be a strategy of complementary energy against the cold season. 4) P. hamadryas only had a midday resting and grooming peak with multi peaks of traveling and playing in the warm season, and the swimming, playing and watching time rhythm had not obvious difference between the cold winter and the warm season, but there were multi peaks of resting in the cold winter. Therefore, their diurnal activity rhythm was not the same as other many primates (such as Nomascus nasutus, Propithecus verreauxi and Lagothrix sp.), the captive P. hamadryas in winter in Hangzhou area took a strategy of feeding for supplement energy to withstand cold rather than resting to reduce energy consumption. In short, Papio hamadryas reflects obvious rhythm with seasonal differences, which may be an adaptation to the influence of food and temperature changes in captivity.

Reduced tumorigenicity and drug resistance through the downregulation of octamer-binding protein 4 and Nanog transcriptional factor expression in human breast stem cells.

Breast cancer is the most common type of malignancy among females. Previous studies examining breast cancer tissue have demonstrated the presence of stem cells, and have detected octamer­binding protein 4 (Oct4) and Nanog transcription factor expression. In the present study, breast cancer stem cells (CSCs) were isolated and enriched from MDA­MB­231 breast cancer cell lines, and were defined as MDA­MB­231 stem cells using flow cytometry. The expression of Oct4 and Nanog in breast CSCs were detected by quantitative polymerase chain reaction and western blotting. RNA interference (RNAi) was used in order to downregulate the expression of Oct4 and Nanog. Drug resistance and tumor­initiating capability following in vivo injection of MDA­MB­231 stem cells trans-duced with negative RNAi, Oct4 RNAi and Nanog RNAi were compared with that of MDA­MB­231 stem cells without siRNA transfection as a control group. In addition the capability of MDA­MB­231 breast cancer cells to initiate tumor formation in mice was compared with that of MDA­MB­231 stem cells. A paclitaxel inhibition test was also conducted in order to detect resistance of MDA­MB­231 breast cancer stem cells to this treatment. The MDA­MB­231 stem cells were revealed to exhibit elevated percentages of the cluster of differentiation (CD)44+CD24­/low subset, high tumorigenicity and resistance to chemotherapy, all of which are characteristic stem cell properties. In addition, the MDA­MB­231 stem cells were more tumorigenic in vivo. Furthermore, the breast CSCs also expressed high levels of the Oct4 and Nanog transcription factors. Therefore, downregulation of Oct4 or Nanog expression may reduce chemotherapeutic drug resistance and tumorigenicity in breast CSCs. In conclusion, Oct4 and Nanog expression may be a key factor in the development of resistance to chemotherapy and tumor growth of breast CSCs. This finding indicates that Oct4 or Nanog­targeted therapy may be a promising means of overcoming resistance to chemotherapy and inhibiting tumor growth in breast cancer treatment.

[The clinical significance of preoperative enteral immune nutrition in patients with malignant gastrointestinal tumors].

OBJECTIVE: To study the impact of preoperative enteral immune nutrition on patients with malignant gastrointestinal tumors. METHODS: 82 patients with malignant gastrointestinal tumors were divided equally into 2 groups:enteral nutrition group (EN) and normal diet group (Control). Enteral Nutritional Emulsion (TPF-T) served as nasogastically-fed liquid diet for the patients in EN group over a period of 7 days prior to surgery. Normal diet was given to the patients in control group under the same condition as those in EN group in terms of calories and nitrogen contents. Enzyme linked immunosorbent assay (ELISA) was performed to determine the quantity of serum albumin (ALB), transferrin protein (TRF), pre-albumin (PA) and retinol binding protein (RBP). Flow cytometry (FCM) was performed to determine T cell subsets. Postoperative complications, resumption of peristalsis, length of hospital stay, and nutritional costs were also recorded. RESULTS: TRF, PA and RBP increased significantly in the patients in EN group compared with those in control group (P < 0.05). The patients in EN group had significantly higher proportions of CD3+, CD4+/CD8+ higher than those of control (P < 0.05). No serious complications (eg. death or gastrointestinal fistula) were found in the patients. The total nutritional cost for the patients in EN group was similar to that of the controls (P > 0.05). The patients in EN group had less postoperative complications, quicker resumption of peristalsis, shorter hospital stay and lower level of postoperative nutrition cost compared with those of controls (P < 0.05). CONCLUSION: Enteral nutrition support can improve the nutritional status and immunity of patients with malignant gastrointestinal tumors, which has both pre-operative and post-operative benefits for the patients.