Chicken single-chain variable fragments against the SARS-CoV spike protein

The major concern for severe acute respiratory syndrome (SARS), caused by the SARS-associated coronavirus (SARS-CoV), is the lack of diagnostic and therapeutic agents. Using a phage display technology in a chicken system, high-affinity monoclonal antibody fragments against the SARS-CoV spike protein were characterized. Ten truncated spike protein gene fragments were expressed in Escherichia coli cells. Following the immunization of chickens with these recombinant spike proteins, two single-chain variable fragment (scFv) antibody libraries were established with short or long linkers to contain 5x10(7) and 9x10(6) transformants, respectively. After four rounds of panning selection, the scFv antibodies of randomly chosen clones were demonstrated by Coomassie blue staining, and verified by western blot analysis. In a comparison of nucleotide sequences with the chicken germline gene, we found that all clones varied in the complementarity-determining regions, that two scFv antibodies reacted significantly with SARS-CoV-infected Vero cells, and that those two specific scFv antibodies recognized the same region of the spike protein spanning amino acid residues 750-1000. In conclusion, the results suggest that the chicken scFv phage display system can be a potential model for mass production of high-affinity antibodies against the SARS-CoV spike protein.     

Prevalence and associated factors of lens opacities among Chinese type 2 diabetics in Kinmen,Taiwan

The aim of this study is to assess the prevalence and associated risk factors of lens opacities among type 2 diabetics in Kinmen, Taiwan. A community-based mass screening ascertained 971 type 2 diabetics from 1991 to 1993. From that population, a total of 578 (59.5%) patients with type 2 diabetes underwent eye screening in 1999 with a 45° thin slit-lamp biomicroscopy and ophthalmoscopy to examine the lens after dilation of the pupils. The prevalence of nuclear, cortical, and posterior subcapsular (PSC) opacity without surgery among type 2 diabetics was 22.5, 20.2, and 19.9%, respectively. The number of females affected was statistically higher than males in each type of lens opacity. The prevalence of each type of lens opacity also showed a statistically significant increase with (χ² test). Based on multiple logistic regressions, age was the most significant factor related with each type of lens opacity. Triglyceride at baseline was associated with nuclear opacity (≥200 vs. <200 mg/dl, OR = 2.35, 95% CI: 1.15–4.79) and PSC opacity (≥200 vs. <200 mg/dl, OR = 2.11, 95% CI: 1.00–4.43). In conclusion, our results show that in addition to age, higher triglyceride level may increase the risk of prevalent nuclear or PSC opacity in type 2 diabetics.     

Effects of Selenium Yeast on Oxidative Stress,Growth Inhibition,and Apoptosis in Human Breast Cancer Cells

Recent evidence suggests that selenium (Se) yeast may exhibit potential anti-cancer properties; whereas the precise mechanisms remain unknown. The present study was aimed at evaluating the effects of Se yeast on oxidative stress, growth inhibition, and apoptosis in human breast cancer cells. Treatments of ER-positive MCF-7 and triple-negative MDA-MB-231 cells with Se yeast (100, 750, and 1500 ng Se/mL), methylseleninic acid (MSA, 1500 ng Se/mL), or methylselenocysteine (MSC, 1500 ng Se/mL) at a time course experiment (at 24, 48, 72, and 96 h) were analyzed. Se yeast inhibited the growth of these cancer cells in a dose- and time-dependent manner. Compared with the same level of MSA, cancer cells exposure to Se yeast exhibited a lower growth-inhibitory response. The latter has also lower superoxide production and reduced antioxidant enzyme activities. Furthermore, MSA (1500 ng Se/mL)-exposed non-tumorigenic human mammary epithelial cells (HMEC) have a significant growth inhibitory effect, but not Se yeast and MSC. Compared with MSA, Se yeast resulted in a greater increase in the early apoptosis in MCF-7 cells as well as a lower proportion of early and late apoptosis in MDA-MB-231 cells. In addition, nuclear morphological changes and loss of mitochondrial membrane potential were observed. In conclusion, a dose of 100 to 1500 ng Se/mL of Se yeast can increase oxidative stress, and stimulate growth inhibitory effects and apoptosis induction in breast cancer cell lines, but does not affect non-tumorigenic cells.     

Volumetric tomography of fluorescent proteins through small animals in vivo

Volumetric detection and accurate quantification of fluorescent proteins in entire animals would greatly enhance our ability to monitor biological processes in vivo. Here we present a quantitative tomographic technique for visualization of superficial and deep-seated (>2-3 mm) fluorescent protein activity in vivo. We demonstrate noninvasive imaging of lung tumor progression in a murine model, as well as imaging of gene delivery using a herpes virus vector. This technology can significantly improve imaging capacity over the current state of the art and should find wide in vivo imaging applications in drug discovery, immunology, and cancer research.     

Finite element analysis of the cervico-trochanteric stemless femoral prosthesis

OBJECTIVE: To investigate the biomechanical performance of a newly designed cervico-trochanteric stemless prosthesis by comparing the stress distribution with that of the traditional stem-type porous-coated anatomic prosthesis. DESIGN: Three-dimensional finite element models were created for the intact femur, cervico-trochanteric implanted femur and porous-coated anatomic implanted femur. The stress distributions on the femur and the implant were compared. The effects of using two or three screws fixation for the cervico-trochanteric implanted femur were also investigated. BACKGROUND: Local bone loss after implantation of traditional stem-type prostheses remains an unsolved problem during the long-term application of total hip replacement. The stress shielding effect and osteolysis were thought to be the two main factors that result in local bone loss after prosthesis implantation. In order to eliminate the mechanical and the biological causes of bone loss after total hip arthroplasty, a newly designed stemless femoral prosthesis was investigated. METHODS: Three-dimensional finite element models were created for the intact, cervico-trochanteric (with two or three fixation screws), and porous-coated anatomic implanted femora with the geometry of a standardized composite femur. Analysis was performed for a loading condition simulating the single-legged stance. The von Mises stress distributions of each model were analyzed and compared. RESULTS: The results can be summarized as follows: (1) Von Mises stress in the proximal, medial femur for the cervico-trochanteric implanted model was higher than that of the intact model and the porous-coated anatomic implanted model; (2) stress-shielding effect of the cervico-trochanteric models (with two or three fixation screws) were eliminated as compared with the porous-coated anatomic model; (3) no obvious difference in von Mises stress distribution for the cervico-trochanteric implanted model with two or three fixation screws. CONCLUSIONS: The cervico-trochanteric femoral prosthesis may reduce the stress-shielding effect of the proximal femur and achieve a more physiological stress distribution on the proximal femur than that of the porous-coated anatomic prosthesis. RELEVANCE: The new concept of cervico-trochanteric stemless prosthesis has proven to possess several advantages based on the current results, and may be an alternative for traditional stem-type prostheses in future clinical applications.     

Report of gossypiboma from the standpoint in medicine and law

We report on a case of gossypiboma. A 78-year-old man was admitted to our hospital with acute abdomen. He had undergone an operation for colon cancer 4 mo previously. Abdominal ultrasonography revealed an echogenic lesion with a hypoechoic rim and strong posterior acoustic shadowing in the lower abdomen. Diagnosis of gossypiboma can be made by ultrasonography to avoid loss-of-chance of survival. We reviewed the English literature briefly of gossypiboma from the medical and juridical view. According to the theory of loss-of-chance, the damage of plaintiff is the loss of the chance of survival or recovery, rather than the final harm. The victim would allow recovery for the loss of the chance from the defendant. But the plaintiff would show by a preponderance that he was deprived of a betterchance of a cure. Under the proposed rule, the compensable value of the victim would be the plaintiff's compensation for the loss of the victim's chance of survival.     

Anti‐Aspergillus human host defence relies on type 1 T helper (Th1), rather than type 17 T helper (Th17), cellular immunity

Both interferon‐γ‐producing type 1 T helper (Th1)‐ and interleukin‐17 (IL‐17)‐producing Th17 cells have been proposed to be involved in anti‐fungal host defence. Although invasive aspergillosis is one of the most severe human fungal infections, little is known regarding the relative importance of the Th1 versus Th17 cellular immune pathways for the human anti‐Aspergillus host defence. Using human peripheral blood mononuclear cells and a system consisting of monocyte‐derived macrophages with lymphocytes, we found that Aspergillus fumigatus is a weak inducer of human IL‐17 but induces a strong Th1 response. These data were validated by the very low IL‐17 levels in bronchoalveolar lavage fluid and serum of patients with invasive aspergillosis. Surprisingly, live A. fumigatus reduced IL‐17 production induced by mitogenic stimuli. This effect was mediated through the propensity of A. fumigatus to metabolize tryptophan and release kynurenine, which modulates the inflammatory response through inhibition of IL‐17 production. In conclusion, A. fumigatus does not stimulate production of IL‐17 and human host defence against aspergillosis may not rely on potent Th17 responses.     

Rsf‐1, a chromatin remodelling protein,interacts with cyclin E1 and promotes tumour development

Chromosome 11q13.5 containing RSF1 (HBXAP), a gene involved in chromatin remodelling, is amplified in several human cancers including ovarian carcinoma. Our previous studies demonstrated requirement of Rsf‐1 for cell survival in cancer cells, which contributed to tumour progression; however, its role in tumourigenesis has not yet been elucidated. In this study, we co‐immunoprecipitated proteins with Rsf‐1 followed by nanoelectrospray mass spectrometry and identified cyclin E1, besides SNF2H, as one of the major Rsf‐1 interacting proteins. Like RSF1, CCNE1 is frequently amplified in ovarian cancer, and both Rsf‐1 and cyclin E1 were found co‐up‐regulated in ovarian cancer tissues. Ectopic expression of Rsf‐1 and cyclin E1 in non‐tumourigenic TP53^mut RK3E cells led to an increase in cellular proliferation and tumour formation by activating cyclin E1‐associated kinase (CDK2). Tumourigenesis was not detected if either cyclin E1 or Rsf‐1 was expressed, or they were expressed in a TP53^wt background. Domain mapping showed that cyclin E1 interacted with the first 441 amino acids of Rsf‐1. Ectopic expression of this truncated domain significantly suppressed G1/S‐phase transition, cellular proliferation, and tumour formation of RK3E‐p53^R175H/Rsf‐1/cyclin E1 cells. The above findings suggest that Rsf‐1 interacts and collaborates with cyclin E1 in neoplastic transformation and TP53 mutations are a prerequisite for tumour‐promoting functions of the RSF/cyclin E1 complex.