Gene for neuraminidase activity on mouse chromosome 17 near h-2: pleiotropic effects on multiple hydrolases.

The low activity of liver neuraminidase that is characteristic of mouse strain SM/J is inherited as a single gene on chromosome 17, near the major histocompatibility complex. This gene, neuraminidase-1 (Neu-1), is represented by the low activity allele Neu-1s in SM/J and the high activity allele Neu-1b in C57BL/6J and most other strains. Previously described variations in the posttranslational processing of acid phosphatase, alpha-mannosidase, arylsulfatase-B, and alpha-glucosidase are attributed to pleiotropic effects of this gene.

Transmission of the fra(X) haplotype from three nonpenetrant brothers to their affected grandsons.

We report on a family showing transmission of the fra(X) gene by 3 nonpenetrant, fra(X) negative, normally intelligent, full and half-brothers to their affected grandsons. The mothers of the affected boys are obligate carriers, fra(X) negative, and of normal intelligence. This family illustrates the "Sherman Paradox" and is compatible with the predictions of the Laird X-inactivation imprinting model. In addition, molecular and/or cytogenetic studies have enabled at-risk relatives to learn more about their carrier fra(X) status and have allowed for more accurate genetic counselling.

[A report of 29 cases of silicosis complicated with mediastinal emphysema].

The experience to treat SCME in the past twenty-three years was reported. The method of upper mediastinotomy for saving the patients was introduced. The authors suggested control of the pulmonary infection and appropriate treatment of pneumothorax are important in preventing the occurrence of mediastinal emphysema.

Both genes and lncRNAs can be used as biomarkers of prostate cancer by using high throughput sequencing data.

OBJECTIVE: To investigate prostate cancer-related genes and lncRNAs by using a high throughput sequencing dataset. MATERIALS AND METHODS: RNA-seq data were obtained from the sequencing read archive database, including both benign and malignant tumor samples. After aligning the RNA-seq reads to human genome reference, gene expression profile as well as lncRNA expression profile was obtained. Next, student's t-test was used to screen both the differentially expressed genes (DEGs) and lncRNAs (DELs) between benign and malignant samples. Finally, goseq was used to conduct the functional annotation of DEGs. RESULTS: A total of 7112 DEGs were screened, such as ZNF512B, UCKL1, STMN3, GMEB2, and PTK6. The top 10 enriched functions of DEGs were mainly related to organism development, including multi-cellular development, system development and anatomical structure development. Also, we discovered 26 differentially expressed lncRNAs. CONCLUSIONS: The analysis used in this study is reliable in screening prostate cancer markers including both genes and lncRNAs by using RNA-seq data, which provides new insight into the understanding of molecular mechanism of prostate cancer.

Knockdown of insulin-like growth factor I receptor inhibits the growth and enhances chemo-sensitivity of liver cancer cells.

Liver cancer is one of the most common malignant cancers worldwide. Systemic chemotherapy remains the major treatment option, but with severe adverse effects. Combinations of systemic with targeted treatments may provide effective therapeutics. The objectives of this study were to demonstrate if insulin-like growth factor-I receptor (IGF-IR) might serve as a functional target for liver cancer treatment and to investigate the chemo-sensitizing activity of IGF-IR downregulation. IGF-IR knockdown was achieved by stable transfection of liver cancer cells with IGF-IR small interfering RNA (siRNA). IGF-IR knockdown resulted in reduced growth, clonogenic survival, adhesion and migration of liver cancer cells, and increased sensitivities of liver cancer cells to apoptosis-inducing agents and chemotherapeutic drugs in vitro. In the animal studies, both IGF-IR knockdown and adriamycin (ADM) treatment significantly reduced the growth of liver tumors. IGF-IR knockdown enhanced the effect of ADM on tumor growth by further reducing tumor angiogenesis and inducing tumor cell apoptosis. The final tumor sizes in the IGFIR-siRNA, ADM-treated EGFP, and ADM-treated IGFIR-siRNA groups were significantly reduced by 52.5%, 33.8%, and 86.3%, respectively, compared with that in the EGFP control, suggesting that the ADM and the IGF-IR knockdown inhibit the growth of liver tumors in a synergistic manner. These results support that IGF-IR may serve as a functional molecular target for liver cancer treatment, and that the combination of systemic chemotherapy with targeted IGF-IR suppression may provide an effective treatment strategy for liver cancer.

Characterization of human placental neuraminidases. Stability, substrate specificity and molecular weight.

1. At least two components of neuraminidase can be distinguished on the basis of thermolability and sedimentability by using the artificial fluorogenic substrate 4-methylumbelliferyl N-acetyl-alpha-D-neuraminate. 2. In crude homogenates, thermodenaturation at 25 degrees C showed a biphasic curve corresponding to component A (half-life, 21 min) and B (half-life, 85 min). The two components were partially resolved by centrifugation. A being soluble and B sedimentable. Both had similar pH-activity curves (pH optimum, 4.4), Km values (A, 0.10 mM; B, 0.06 mM) and molecular weight as determined by radiation inactivation (A, 67000; B, 63000). 3. The soluble A form was still aggregated or bound to membranous debris since almost all neuraminidase activity was eluted near or at the void volume of a Sephacryl S-300 column. 4. Both soluble and sedimentable fractions of placenta hydrolysed the GD1A ganglioside and N-acetyl-neuraminyl-D-lactose linearly for 12 h but no fetuin hydrolysis was detected. 5. The neuraminidase activity with the artificial fluorogenic substrate was inhibited by N-acetylneuraminyl-D-lactose but not by the GD1A ganglioside. These preliminary results suggest that there exist two closely related enzymes hydrolysing both the artificial substrate and N-acetylneuraminyl-D-lactose and a third one hydrolysing the GD1A ganglioside exclusively.