Evaluation of Femoral Head Perfusion by Contrast-Enhanced Ultrasound in a Rabbit Model of Steroid-Induced Osteonecrosis.

OBJECTIVES: To study the technical feasibility of contrast-enhanced ultrasound (CEUS) in evaluating femoral head perfusion in a rabbit model of steroid-induced femoral head osteonecrosis. METHODS: Twenty rabbits were divided randomly into a control group (n = 8) and an experimental group (n = 12). Rabbits in the experimental group were induced by lipopolysaccharide and methylprednisolone to build a model of steroid-induced femoral head osteonecrosis. Contrast-enhanced ultrasound examinations were performed at 3 and 5 weeks after induction. Then, pathologic examinations and microvessel density (MVD) calculations were performed on the excised rabbit femoral heads. RESULTS: The MVD of the experimental group decreased significantly 3 and 5 weeks after induction compared with that of the control group. According to the CEUS examination results, significant differences existed in the ascending slope, descending slope, mean transit time, and time to peak between the groups at 5 weeks (P < .05). A correlation analysis showed that the descending slope had a certain correlation with the MVD (correlation coefficient, 0.376). A receiver operating characteristic curve was used to analyze the capacity of the CEUS parameters to predict the occurrence of osteonecrosis. The areas under the curve for the ascending slope and descending slope were 0.758 and 0.760, respectively (P < .05). CONCLUSIONS: Contrast-enhanced ultrasound can visualize the microcirculation in steroid-induced osteonecrosis of the femoral head in rabbits and may be a useful imaging method for the early monitoring and prediction of femoral head osteonecrosis.

A field survey for Wolbchia and phage WO infections of Aedes albopictus in Guangzhou City, China.

Wolbachia are maternal endosymbiotic bacterium, which infect a diverse range of arthropods, ranging from 20 to 76% in nature. They are capable of inducing a wide range of reproductive abnormalities to their hosts, such as cytoplasmic incompatibility (CI), which has been proposed to be used as a tool to modify mosquitoes that are resistant to the development of pathogen, as an alternative vector control strategy. Here, we evaluated the prevalence of Wolbachia and phage WO infections in the field population of Aedes albopictus in Guangzhou City via polymerase chain reaction (PCR) assay using the Wolbachia specific Wolbachia surface protein (wsp) and phage WO orf7 gene primers. Based on the results of PCR and phylogeny analysis, we found that A. albopictus in Guangzhou City were infected with two Wolbachia strains, wAlbA and wAlbB. Phage WO, the virus-infected Wolbachia, was also detected in A. albopictus. One hundred and ten female individuals were screened via PCR, with 109 super-infected with Wolbachia and one sample single-infected with wAlbB strain. And 104 of 113 male individuals were both infected with wAlbA and wAlbB, and nine male samples were found to be infected with wAlbA strain only. The infection rates of phage WO in female and male individuals were 82.73 and 46.02%, respectively. These results showed that the natural Wolbachia and phage WO infections in A. albopictus population in Guangzhou were at a higher frequency at present, indicating that Wolbachia appear to be a better candidate nature resource for biological control insect vectors to reduce vector-borne diseases.

Laccase2 is required for sclerotization and pigmentation of Aedes albopictus eggshell.

Laccase (EC 1.10.3.2) is a member of multicopper oxidases that have been found in higher plants, fungus, bacterium, and insects. Two types of laccase genes have been detected in many species of insects: laccase1 and laccase2. It has been identified that laccase2 enzyme may play a key role in sclerotization and pigmentation of insect cuticle. But few attentions were given to the biological role of laccase2 in the synthesizing of similar structures, such as oothecae, eggshell, or silk cocoons. We cloned laccase2 gene from Aedes albopictus, one main mosquito vector of dengue virus in China. An upregulation of laccase2 gene was observed after a blood meal in female adult mosquitoes, suggesting that laccase2 gene may have an involvement in the development of ovary. RNA interference experiment was performed by using adult female mosquitoes. Female mosquitoes were injected with 20 ng of double-strain RNA into the thorax. Pigmentation of mosquito eggshell was blocked that these eggs never became dark. And the incomplete sclerotization of eggshell weakened the stability and flexibility of the eggs. These eggs without enough protection were deformed and died in water. These results demonstrate that laccase2 plays a critical role in the development of eggs of A. albopictus. Laccase2 may provide a novel target for mosquito control and management.

Molecular cloning, expression, and characterization of a putative activation-associated secreted protein from Angiostrongylus cantonensis.

Activation-associated secreted protein (ASP) had been found in many helminthes, which was associated with pathogenesis and stage transition. A complementary DNA (cDNA) sequence encoding a putative two-domain ASP was obtained from an Angiostrongylus cantonensis fourth-stage larvae cDNA library, which we designated as AgASP. The cDNA of AgASP contains an open reading frame encoding 424 amino acids, the first 19 residues being a putative secretion signal. The expression pattern of this protein was investigated by real-time polymerase chain reaction and Western blot. We found that this protein expressed most highly in the brain-stage larvae (Lbr) of this parasite and existed in the excretory/secretory products of this stage. Immunofluorescence showed it existed in the lumen of the Lbr. The recombinant protein can be recognized by the infection sera from mice (nonpermissive host), while it cannot be recognized by infection sera from rats (permissive host). The infiltration of neutrophils in infected nonpermissive host can be lessened by immunizing this host with this protein (immunized vs control group, 13.7 ± 10.2 vs 65.5 ± 19.2). These findings suggest that this protein plays a role in the pathogenesis of human angiostrongyliasis and is worthy of further study.

Management of esophagogastric fistula caused by adjustable gastric band erosion: A case report and literature review.

Laparoscopic adjustable gastric banding (LAGB) is commonly used in the treatment of morbid obesity. However, with clinical application and long-term follow-up, the shortcomings of this procedure were also exposed, bringing about surgery-related complications include dysphagia, intragastric band migration, slippage, and gastric band erosion. Lower esophageal and gastric fistula is a rare but dangerous complication after LAGB. We describe a case of esophagogastric fistula occurring twelve years after a laparoscopic band procedure and its successful management in a multidisciplinary and staged manner, followed by a short review of the literature.

Comprehensive analysis of the prognostic and immunotherapeutic implications of STAT family members in human colorectal cancer.

Background: Colorectal cancer (CRC) is the third most prevalent cancer worldwide and the second leading cause of cancer mortality. Signal transducer and activator of transcription (STAT) proteins are a group of transcription factors implicated in cell signal transduction and gene transcription in several cancer types. However, the level of expression, genetic alterations, and biological function of different STATs, as well as their prognostic and immunotherapeutic value in CRC remain unclear. Methods: The mRNA and protein expression levels, genetic alterations, prognostic value, gene-gene and protein-protein interaction networks, and biological function of STATs in CRC were studied using the GEPIA, HPA, cBioPortal, PrognoScan, Kaplan-Meier plotter, GeneMANIA, STRING, and Metascape databases. The expression of STATs in CRC was confirmed using immunohistochemistry (IHC). Finally, the relationship between STAT expression and immune infiltration as well as immunotherapy-associated indicators was also investigated. Results: The expression levels of STAT2/5A/5B are downregulated in CRC, and the STAT1/3/4/5B expressions were significantly associated with the tumor stage of patients with CRC. The abnormal expression of STAT2/4/5B in patients with CRC is related to the prognosis of patients with CRC. The STATs and their neighboring proteins are primarily associated with lymphocyte activation, cytokine-mediated signaling pathways, positive regulation of immune response, regulation of cytokine production, and growth hormone receptor signaling pathways in cancer. The expression of STATs was significantly associated with immune infiltration and immunotherapy response-associated indicators. Conclusion: This study may help further understand the molecular mechanism of CRC and provide new prognostic biomarkers and immunotherapy targets in patients with CRC.

Evidences for B6C3-Tg (APPswe/PSEN1dE9) double-transgenic mice between 3 and 10 months as an age-related Alzheimer's disease model.

Transgenic mouse has shown great advantages in the study of Alzheimer's disease (AD) and drug screening as AD develops rapidly resent years, while more detail information of these transgenic mice and experience of application are needed. To obtain the basic background information of the B6C3-Tg (APPswe/PSEN1dE9) double-transgenic mouse, which was reported with early onset AD, three- to ten-month-old B6C3-Tg AD mice and normal C57BL/6 mice were selected randomly to test the ability of learning memory by Morris water maze, the brain acetylcholinesterase (AChE) activity by AChE kit, and beta amyloid protein level by immunohistochemistry staining. Compared with the control group, the escape latency time of B6C3-Tg AD mice at 9 and 10 months of age is significantly longer (P < 0.05) in Morris maze test, and the activity of brain AChE is higher. ß-Amyloid plaques were observed at 3 months of age and developed rapidly. Statistical analysis showed a positive correlation between the area of these plaques and the ages of B6C3-Tg AD mouse (y = 0.0355e(0.5557x), R = 0.9557). The model's behavior is conformed to simulate behaviors of human Alzheimer's disease at the early stage and may provide detail background information a new choice when transgenic mice are needed in the research of AD.

Characterization and immunolocalization of mutated ornithine decarboxylase antizyme from Angiostrongylus cantonensis.

Ornithine decarboxylase antizyme (OAZ), a prominent regulator of cell proliferation, DNA/RNA transformation and tumorigenesis, can bind to ornithine decarboxylase (ODC) and facilitate its degradation. Expression of OAZ requires a unique ribosomal frame shift that is regulated by levels of polyamine in the cell. In this study, we cloned an OAZ gene with the +1 ribosomal frame-shift from a fourth-stage larvae cDNA library of Angiostrongylus cantonensis. We removed one nucleotide to express the gene without polyamine. The sequence analysis showed that the deleted-mutation ornithine decarboxylase antizyme (DM-AcOAZ) contained a conservative domain related to other species OAZ. Quantitative real-time PCR revealed that DM-AcOAZ was expressed in L3 and L4 stages and adult female worms. More notably the expression level is the highest in the adult female stage. Immunohistochemical studies indicated that DM-AcOAZ was specifically localized in the uterus, oocyte and intestine in adult female worms. MTT assays showed that in DM-AcOAZ transfected HeLa cells, cell proliferation is inhibited. In conclusion, DM-AcOAZ may be a female-enriched protein and may involved in the cell proliferation in A. cantonensis.

Differential proteomics of Aedes albopictus salivary gland, midgut and C6/36 cell induced by dengue virus infection.

The interaction between dengue virus (DENV) and vector mosquitoes are still poorly understood at present. In this study, 2-D DIGE combined with MS was used to analyze the differential proteomes of Aedes albopictus salivary gland, midgut and C6/36 cells induced by DENV-2. Our results indicated that the virus infection regulated several functional classes of proteins. Among them, 26 were successfully analyzed by real-time RT-PCR. The mRNA levels of 15 were the highest in salivary gland, 2 in midgut and none in C6/36 cells, however, 18 were the least in fat body compared to other organs. Interestingly, the changes of differential proteins mRNA were the most obvious in fat body post-infection. Chaperone, cytoskeleton and energy metabolism enzyme were the most down- or up- regulated proteins after DENV-2 infection. The abundant expression of these proteins in salivary gland may relate to its high susceptibility.