A Parotid Gland Mammary Analogue Secretory Carcinoma in a 4-Year-Old Boy: Case Report and Literature Review.

Background: Mammary analogue secretory carcinoma (MASC) is characterized by similar histologic, immunohistochemical, and molecular features with breast secretory carcinoma. MASC usually occurs in adults. Case report: A 4-year-old boy presented with a right infra-auricular mass. Features of the tumor include solid, tubular, and papillary growth patterns, with homogenous eosinophilic secretions inside microcystic structures. Immunohistochemical stains showed strong, diffuse staining for CK7, S100, pan-TRK protein. P63 was positive in a peripheral pattern. Fluorescence in situ hybridization (FISH) analysis showed the characteristic ETV6-NTRK3 gene fusion. Conclusion: Typical histological, immunohistochemical, and molecular features are present in MASC occurring early in childhood.

Ribosome assembly factor URB1 contributes to colorectal cancer proliferation through transcriptional activation of ATF4.

Ribosome assembly factor URB1 is essential for ribosome biogenesis. However, its latent role in cancer remains unclear. Analysis of The Cancer Genome Atlas database and clinical tissue microarray staining showed that URB1 expression was upregulated in colorectal cancer (CRC) and prominently related to clinicopathological characteristics. Silencing of URB1 hampered human CRC cell proliferation and growth in vitro and in vivo. Microarray screening, ingenuity pathway analysis, and JASPAR assessment indicated that activating transcription factor 4 (ATF4) and X-box binding protein 1 (XBP1) are potential downstream targets of URB1 and could transcriptionally interact through direct binding. Silencing of URB1 significantly decreased ATF4 and cyclin A2 (CCNA2) expression in vivo and in vitro. Restoration of ATF4 effectively reversed the malignant proliferation phenotype of URB1-silenced CRC cells. Dual-luciferase reporter and ChIP assays indicated that XBP1 transcriptionally activated ATF4 by binding with its promoter region. X-box binding protein 1 colocalized with ATF4 in the nuclei of RKO cells, and ATF4 mRNA expression was positively regulated by XBP1. This study shows that URB1 contributes to oncogenesis and CRC growth through XBP1-mediated transcriptional activation of ATF4. Therefore, URB1 could be a potential therapeutic target for CRC.

Diagnostic performance of two specific schistosoma japonicum immunological tests for screening schistosoma haematobium in school children in Zambia.

Dipstick Dye Immunoassay (DDIA) and Indirect Haemagglutination Assay (IHA), are two commercially available kits which have been widely used for screening Schistosoma japonicum in P.R. China. Whether they can be used for screening of Schistosoma haematobium are not clear. In order to evaluate the diagnostic efficiency of DDIA and IHA for screening Schistosoma haematobium, serum samples were collected from pupils in endemic areas in Zambia, Southern Africa, and tested by DDIA and IHA by single-blind manner. Meanwhile, the pupils were microscopically examined by infection with Schistosoma and soil-transmitted helminths, visually observed for parasite eggs. Of the enrolled 148 pupils, 61% tested positive for S. haematobium infection, while 31% and 36% of pupils were infected with hookworm and Ascaris respectively. Regarding the parasitological tests as reference standard, for the diagnosis of S. haematobium infection, IHA performed higher sensitivity (74%, 95% CI: 65%-83%) than that of DDIA (60%, 95%CI: 49%-70%). The sensitivities of IHA and DDIA are significant higher in 10-14 years old students than those of 7-9 years old group. The specificity of DDIA and IHA were 61% (95%CI: 49%-74%) and 72% (95%CI: 60%-84%), respectively. The co-infection with STHs decreased the specificity of DDIA but had no impact on that of IHA. Our study indicated that IHA has more potential as an alternative diagnostic tool for identifying schistosomiasis haematobium but need further improvement.

[Effects of Tcd A on Rho GTPases and the Cytoskeleton of Leukemia Cell Line K562].

OBJECTIVE: To investigate the effect of clostridium difficile toxin A(TcdA) on the Rho GTPases and the cytoskeleton in K562 cells. METHODS: K562 cells were cultured in vitro with different concentration of TcdA.The effect of TcdA proliferation of cells was detected by MTT method after the K562 cells were stimulated with TcdA for 24,48 and 72h; the expression of cdc42, RhoA, Rac1 mRNA was assessed by RT-PCR; the changes of the microtubule, the microfilament were observed by confocal laser scanning microscopy. RESULTS: The proliferation of K562 cells was inhibited after exposure to TcdA for 24, 48 and 72h, and the inhibitory rate was 47.67% in the treatment for 48 h. the cdc42，RhoA and Rac1 mRNA expressions in the experimental groups decreased after treated with TcdA(P<0.05), which positively correlated with concentration of TcdA. Also, the microfilament decreased ,which was observed by confocal laser scanning microscopy. CONCLUSION: TcdA inhibites K562 cell proliferation and induces apoptosis, TcdA can change the cytoskeleton structure through the cytoskeletal protein genes cdc42 and RhoA, Rac1 mRNA expression,. It is related with cell microfilament content decreasing.

Transient embolization with microspheres of polyhydroxyalkanoate renders efficient adenoviral transduction of pancreatic capillary in vivo.

BACKGROUND: Our previous study showed an efficient targeting of islets of Langerhans by adenoviral injection via the celiac trunk. Unexpectedly, none of the endothelial cells was infected given the direct contact between adenoviruses and the capillary wall. The present study intended to provide an efficient approach for adenoviral targeting of the microcapillary endothelial cells in the pancreas. METHODS: We prepared microspheres of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) with a size comparable to the diameter of capillary (5-10 µm). Scanning electron microscopy was applied to verify that adenoviruses carrying a green fluorescence protein gene were complexed with PHBHHx-microspheres after 30 min of co-incubation. The complexes were then injected into the pancreas of mice via the celiac trunk. RESULTS: Approximately 40% of endothelial cells in the pancreas were labeled 5 days after surgery. Islet cells were labeled occasionally, whereas labeling of the acinar and ductal tissues was barely detectable. Endothelium targeting was inefficient in other internal organs. Consistent with the reported superior tissue compatibility of PHBHHx, no discernable microspheres were found in all of the organs examined. Furthermore, splenocyte activation was dampened when adenoviruses were complexed with the microspheres. CONCLUSIONS: The present study has established an approach for efficient pancreatic capillary targeting by using microsphere-adenoviral complexes. This procedure could be invaluable for the treatment of capillary-related diseases.

Nicotinic acid inhibits glucose-stimulated insulin secretion via the G protein-coupled receptor PUMA-G in murine islet ß cells.

OBJECTIVES: Chronic administration of nicotinic acid (NA), a potent antilipidemic compound, aggravates glycemic control in diabetic patients. It is not known if NA has direct effects on islet ß cells. METHODS: Real-time reverse transcriptase-polymerase chain reaction, in situ hybridization, and immunofluorescence techniques were used to examine the expression of NA receptor PUMA-G, a member of the G protein-coupled receptor (G-PCR) family, in murine islet ß cells. Calcium transient was measured using confocal microscopy, whereas the intracellular cyclic adenosine monophosphate and glucose-stimulated insulin secretion (GSIS) from isolated islets were determined by the enzyme-linked immunosorbent assay. RESULTS: High levels of PUMA-G transcripts and protein were detected in all ß cells, and about 40% of α cells. PUMA-G transcripts increased more than 3-fold in islets incubated with interferon γ. Cyclic adenosine monophosphate accumulation, induced by IBMX/forskolin, was inhibited by NA; however, the inhibition was completely abolished by pretreatment of the culture with pertussis toxin. No calcium transient was detected in islet cells in the presence of NA. Static incubation of islets with NA led to an approximately 30% reduction of GSIS. CONCLUSIONS: The results indicated that PUMA-G stimulation by NA in islet ß cells inhibited GSIS likely via activation of the Gi signaling pathway.

An assessment of the risks of carcinogenicity associated with polyhydroxyalkanoates through an analysis of DNA aneuploid and telomerase activity.

Polyhydroxyalkanoates (PHA) are aliphatic polyesters synthesized by many bacteria. Because of their flexible mechanical strengths, superior elastic property, biodegradability and biocompatibility, PHA have been developed for applications as medical implants, drug delivery matrices, and devices to support cell growth. Lots of studies showed that PHA matrices improved cell proliferation and tissue regeneration. However, the possibility of whether rapid cell proliferation on PHA matrices will induce tumor formation is unclear. Here we confirmed that proliferating rat osteoblasts grown on films of various PHA including PHB, PHBV, P3HB4HB, PHBHHx and PHBVHHx did not lead to cancer induction at least for p8th. Cell proliferation was evaluated by the incorporation of 5-bromodeoxyuridine (BrdU), the transcript expression of cancer related genes Ki67, p53 and c-Fos was monitored by quantitative Real-time PCR, the results showed the cells proliferating on the PHA films were under normal cell cycle regulation. Moreover, DNA aneuploid and telomerase activity were only detected in the positive control UMR-108 cells; compared with cells grown on films, UMR-108 cells had longer telomeres, further demonstrated the normal status of cells proliferating on the PHA films. It indicated that the above PHA family members could be used to support cell growth without indication of susceptibility to tumor induction. These results will be important for promoting the application of PHA as new members of biomaterials.

The use of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) scaffolds for tarsal repair in eyelid reconstruction in the rat.

Tarsal repair is an important part for eyelid reconstruction. Presently traditional clinic treatments do not produce satisfactory repair effects. The key is to find a proper tarsal repair material. Microbial poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) was studied for application as tarsal substitute in this study. PHBHHx scaffolds were implanted into tarsal defects of Sprague-Dawley rats. Eyelid samples of implanted materials and blank defect controls were collected for histological examination at weekly intervals post surgery. Results were compared among PHBHHx scaffolds, commercial acellular dermal matrices (ADM) and blank defect controls. Both PHBHHx scaffolds and ADM provided satisfactory repair results compared with the blank controls even though the implanted PHBHHx scaffolds showed a 2 weeks inflammation. Fibrous encapsulation and scaffold degradation were observed for the PHBHHx implants. Combined with its strong, elastic mechanical properties, the tissue compatible and biodegradable PHBHHx was proven to be a suitable candidate for tarsal repair.

[Preparation and characterization of monoclonal antibody against Clostridium difficile toxin A].

AIM: To prepare monoclonal antibodies (mAbs) against Clostridium difficile toxin A and identify their properties. METHODS: BALB/c mice were immunized with C.difficile toxin A. The splenocytes from immunized mice were fused with myeloma cells Sp2/0. The hybridoma cells were screened by indirect ELISA and limiting dilution method. The titer and relative affinity of ascitic mAbs were determined by ELISA. Specificity of mAbs was analyzed by Western blot. RESULTS: Six hybridoma cell lines (2H7, 3E9, 4B5, 5C10, 6G8 and 8A1) secreting mAbs against C.difficile toxin A were obtained. The Ig classes and subclasses of mAbs 2H7, 3E9 and 6G8 were IgM, mAbs 4B5 and 8A1 were IgG1, and mAb 5C10 was IgG2a. All 6 mAbs had no neutralization activity. Epitope recognized by 5 mAbs(2H7, 4B5, 5C10, 6G8 and 8A1) differed from that by mAb 3E9. Relative affinities of mAbs 8A1 and 4B5 were all above 10(5), and those of other 4 mAbs were 10(4). Western blot analysis no-denatured PAGE showed that all 6 mAbs reacted to C.difficile toxin A with M(r) being 55 x 10(4), and under the condition of denatured SDS-PAGE, Western blot analysis showed that all 6 mAbs reacted to subunits of C.difficile toxin A with M(r) being 5 x 10(4)-24 x 10(4). CONCLUSION: Six mAbs against C.difficile toxin A with high titers were obtained successfully with satisfactory specificity and relative affinity, which will be useful for detection of C.difficile toxin A.