[Morphogenesis of AcMNPV nucleocapsid]

In this paper we reported that the nucleocapsid morphogenetic process of AcMNPV in which polyhedrin gene was deleted in the nuclei of sf9 cells. First, the capsid proteins entered the nuclei and assembled many 34nm diameter long fascicularly arranged hollow-tube structures. Then viral DNA entered these tubes that turned into solid structure with high electronic density. The solid structure separated at a certain distance to form 34 x 26 nm fascicular bacilliform structure known as nucleocapsid. Finally, fascicular nucleocapsids were wrapped by envelope and became complete multicapsid morphotype viron.

Combining information within and between pedigrees for mapping complex traits

This paper is concerned with efficient strategies for gene mapping using pedigrees containing small numbers of affecteds and identity-by-descent data from closely spaced markers throughout the genome. Particular attention is paid to additive traits involving phenocopies and/or locus heterogeneity. For a sample of pedigrees containing a particular configuration of affecteds, e.g., pairs of siblings together with a first cousin, we use a likelihood analysis to find 1-df statistics that are very efficient over a broad range of penetrances and allele frequencies. We identify configurations of affecteds that are particularly powerful for detecting linkage, and we show how pedigrees containing different numbers and configurations of affecteds can be efficiently combined in an overall test statistic.

Experimental study on effect of traditional bone-knitting drugs on traumatic gu bi (bone-rheumatoid lesions)

Traditional bone-knitting drugs (TBKD) are used frequently in the treatment of bone fractures. An animal model of Gu Bi (bone-related rheumatoid lesions) with defects of articular cartilage as the main lesion was developed by surgical trauma under the stereomicroscope in Wistar rats and treated with TBKD. The results showed that TBKD could promote proliferation of cartilage cells around the traumatic site and improve the osteogenetic function in the traumatic state, suggesting that TBKD can be used in combination with other Chinese drugs to treat Gu Bi, including bony lesions of the late-stage rheumatoid arthritis and bony arthritis. But the experimental results also suggested that TBKD might have an effect of promoting development of inflammation, and therefore, should be used with care in the acute phase of inflammation.

The cardiac troponin T alternative exon contains a novel purine-rich positive splicing element

We have characterized a novel positive-acting splicing element within the developmentally regulated alternative exon (exon 5) of the cardiac troponin T (cTNT) gene. The exon splicing element (ESE) is internal to the exon portions of the splice sites and is required for splicing to the 3' splice site but not the 5' splice site flanking the exon. Sequence comparisons between cTNT exon 5 and other exons that contain regions required for splicing reveal a common purine-rich motif. Sequence within cTNT exon 5 or a synthetic purine-rich motif facilitates splicing of heterologous alternative and constitutive splice sites in vivo. Interestingly, the ESE is not required for the preferential inclusion of cTNT exon 5 observed in primary skeletal muscle cultures. Our results strongly suggest that the purine-rich ESE serves as a general splicing element that is recognized by the constitutive splicing machinery.

Regulation of myeloblastin messenger RNA expression in myeloid leukemia cells treated with all-trans retinoic acid

Retinoic acid is known to induce differentiation of human myeloid leukemia cells in vitro. Recently, all-trans retinoic acid has been used to induce remissions in patients with acute promyelocytic leukemia, probably through differentiation of the leukemia cells. Myeloblastin (mbn) is a protease that has been identified in the human leukemia cell line HL-60. Downregulation of this protease can inhibit proliferation and induce differentiation of HL-60-derived leukemia cells. Here we have investigated the regulation of mbn messenger RNA (mRNA) expression in two human leukemia cell lines, HL-60 and NB4, treated with all-trans retinoic acid. Under this treatment, downregulation of mbn mRNA was observed in both cell lines, but was considerably delayed in NB4 cells that carry the t(15;17) translocation characteristic of acute promyelocytic leukemia. We have found that multiple mechanisms were involved in the control of mbn mRNA expression. These mechanisms were different in HL-60 and NB4 cells. Our results show that in HL-60 cells, all-trans retinoic acid rapidly decreased transcription of mbn. In contrast, in the t(15;17)-positive NB4 cells treated with all-trans retinoic acid, upregulation of mbn mRNA expression was followed by a late downregulation, both achieved via posttranscriptional mechanisms.

Intestinal helminthiasis in ex-patriates returning to Britain from the tropics. A controlled study

A retrospective study was performed of clinical features in expatriates attending the Hospital for Tropical Diseases, London, with a sole diagnosis of ascariasis (100), trichuriasis (100), hookworm (75), and strongyloidiasis (36). Results were compared with a control group of 100 ex-patriates attending the same hospital in whom no diagnosis was made and in whom stool microscopy and peripheral blood eosinophil counts were normal. Almost one half of all patients with intestinal helminthiasis were asymptomatic. Of those with symptoms specific clinical features were no different from controls with the exception of a transient itch or rash in patients with strongyloidiasis. The presence of eosinophilia was not a reliable indicator of infection. This study suggests that it may be worth while performing stool microscopy in ex-patriates returning from the tropics even if they are asymptomatic.