PYCNOGENOL chewing gum minimizes gingival bleeding and plaque formation.

PYCNOGENOL is an antioxidant phytochemical shown to have antiinflammatory activity in both the in vitro and in vivo models. This study compared the effects of chewing gums with and without PYCNOGENOL on gingival bleeding and plaque formation in 40 human subjects. In this double-blind study, subjects were assigned randomly to receive either control gums without PYCNOGENOL or experimental gums containng 5 mg PYCNOGENOL. Subjects used chewing gums for 14 days. Gingival bleeding and plaque scores were taken before and after the experiment. PYCNOGENOL chewing gums significantly reduced gingival bleeding, while no changes were noted in bleeding indexes in control subjects who used regular chewing gums. Subjects using regular control gums had significant increases of dental plaque accumulation during the two-week period. No increases in plaque accumulation were noted in subjects using PYCNOGENOL chewing gums. The data of this study suggest that the use of Pycnogenol chewing gums can minimize gingival bleeding and plaque accumulation.     

Pre‐copulation intervals,copulation frequencies,and initial progeny sex ratios in two biotypes of whitefly,Bemisia tabaci

The whitefly Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) is a species complex, and its systematic classification requires controlled crossing experiments among its genetic groups. Accurate information on pre‐copulation intervals, copulation frequencies, and initial frequency of egg fertilization of newly emerged adults is critical for designing procedures for collecting the virgin adults necessary for these experiments. In the literature, considerable variation is reported between B. tabaci populations, with respect to the length of the pre‐copulation interval and the initial frequency of egg fertilization. Here, we used a video‐recording method to observe continuously the copulation behaviour of the Mediterranean/Asia Minor/Africa (B biotype) and the Asia II (ZHJ1 biotype) groups of B. tabaci. We also recorded the initial frequency of egg fertilization, as determined by the sex of the progeny. When adults were caged in female–male pairs on leaves of cotton plants, the earliest copulation events occurred 2–6 h after emergence; at 12 h after emergence 56–84% of the females had copulated at least once, and nearly all (92–100%) had copulated at least once by 36 h after emergence. Both females and males copulated repeatedly. Approximately 80 and 20% of copulation events occurred during the photophase and scotophase, respectively. By 72 h post‐emergence, the females of the B and ZHJ1 biotypes had copulated on average 6.1 and 3.9 times, respectively. When adults were caged in groups on plants 1–13 h after emergence, 30–35% of the eggs deposited during this period were fertilized, and approximately 90% of females were fertilized by the end of the 13 h. Although timing of copulation differed in detail between the two genetic groups, the results demonstrate that B. tabaci adults can start to copulate as early as 2–6 h post‐emergence and the majority of females can become fertilized on the day that they emerge.     

BJ-HCC-20, a potential novel cancer-testis antigen.

In an effort to identify novel Cancer-Testis genes, we analyzed the sequence in the q26-28 region of human X chromosome by several on-line tools. The candidate sequences were then confirmed by experiments. We have obtained a novel Cancer-Testis gene, BJ-HCC-20. In vivo, it was found to have two isoforms. In samples of liver, colon, gastric and lung cancer tested, the expression frequency of BJ-HCC-20 is 25%, 17%, 21% and 15%, respectively. Full-length cDNAs of both BJ-HCC-20 isoforms were isolated and their gene structures and promoter regions were characterized. BJ-HCC-20 might have implications in theoretical and practical tumor biology.     

Fibronectin-degrading proteases from the membranes of transformed cells

The local degradation of fibronectin substrata by Rous sarcoma virus-transformed chick embryonic fibroblasts requires cell-contact-related metalloendoprotease and serine-protease activities. Using fibronectin-containing SDS gels, two large proteases with apparent molecular weights of 120K and 150K were found only in the membrane fraction of transformed cells and were absent in normal cells. Both 120K and 150K proteases were active at neutral pH, but showed preferential inhibitor sensitivities of serine and metal proteases, respectively. The 150K protease appeared to account for most of the proteolytic activity since metalloendoprotease inhibitors completely blocked proteolytic activity of the 150K in fibronectin gels, more than 80% of the fibronectin-degrading activity of solubilized membranes, and largely suppressed the appearance of fibronectin degradation spots in cultures of transformed cells.     

Phosphodiester bond cleavage outside mitochondria is required for the completion of protein import into the mitochondrial matrix

The present studies show that hydrolysis of a phosphodiester bond, most likely ATP, is a distinct, second step required to complete import of the F1-ATPase beta-subunit into the mitochondria. This step follows a membrane potential-dependent first step. We show, using an inhibitor of adenine nucleotide transport and the analogue beta,gamma-AMP-PCP, that the activity required for this phosphodiester hydrolysis-dependent completion of protein import resides outside the mitochondrial inner membrane. This activity is proposed to act on the precursor at the site of translocation either to render it competent or to catalyze its vectorial movement directly through the import apparatus. This activity shares properties ascribed to proteins of the heat-shock family, which are proposed to participate in the ATP-dependent refolding of partially denatured proteins and nascent peptides.     

Antimutagenic effect of garlic (Allium sativum L.) on 4NQO-induced mutagenesis in Escherichia coli WP2

Aqueous extract prepared from garlic bulbs markedly suppressed the mutagenesis in both E. coli WP2 trp- and E. coli WP2 trp- uvrA- induced by 4-nitroquinoline 1-oxide (4NQO), but not that induced by UV. Cellular toxicity, inhibition of the expression of the Trp+ phenotype and delay of the first cell division after 4NQO treatment were not observed in the presence of the extract. Since the extract showed identical antimutagenic effects against 4NQO in both test strains but no effect on the mutagenesis of UV, it seems that the extract might act by inactivating the electrophilic group(s) of 4NQO or inhibiting its metabolic activation.     

Regulation of human T cell leukemia virus expression

Retroviruses of the type C morphology have been implicated in a wide variety of diseases in animals and humans. The human T cell leukemia viruses types I (HTLV-I) and II (HTLV-II), the prototypic human-type C retroviruses, have been identified as the causative agents of some forms of human leukemia and neurological disorders. The genetic structure and regulation of the HTLVs are more complex than their avian and murine leukemia virus counterparts. In addition to the gag, pol, and env genes that encode the characteristic virion proteins of all replication competent retroviruses, the genomes of HTLV encode the non-structural proteins, Tax and Rex, which are required for regulating viral gene expression. To understand what appears to be a complex mechanism of disease induction by HTLV, elucidating the regulation and function of the viral gene products and the interaction of these products with each other, as well as with cellular factors, will be critical. This review focuses primarily on regulation of HTLV gene expression in the infected human T lymphocyte, but also discusses analogous gene regulation by the human immunodeficiency virus (HIV). It concentrates specifically on the role these gene products play in virus replication and, ultimately, pathogenesis.     

Phase I study of combination recombinant interleukin-2 and interferon gamma in patients with advanced malignancies

A phase I trial of interleukin-2 and interferon gamma combination treatment in patients with advanced malignancies was performed based on preclinical in vitro and in vivo data which demonstrated synergistic antitumor effect. The toxicities, immune parameters, and tumor responses are described. The clinical and biologic maximal tolerated doses were extrapolated from these data.     

Pre-lysosomal divergence of alpha 2-macroglobulin and transferrin: a kinetic study using a monoclonal antibody against a lysosomal membrane glycoprotein (LAMP-1)

We have used electron microscopic immunocytochemistry to compare the distribution of LAMP-1, a marker for lysosomal membranes, with the intracellular localization of alpha 2-macroglobulin (alpha 2-M) and transferrin at various time points after their endocytosis into cultured NIH 3T3 cells. The purposes of this study were (a) to determine how soon endocytic ligands reach lysosomal organelles, (b) to examine whether the intermediate endocytic vesicles gained lysosomal markers gradually or in a precipitous, discrete event, and (c) to examine the relationship, if any, between the pathway of recycling ligands and lysosomes. At early time points (0-5 min) after initiation of endocytosis, most structures containing alpha 2-M labeled with colloidal gold (receptosomes) were not labeled by anti-LAMP-1 detected using ferritin bridge or peroxidase immunocytochemistry. At late time points (greater than or equal to 15 min), the structures containing alpha 2-M (lysosomes) were strongly labeled by anti-LAMP-1. In contrast, transferrin that was directly labeled with ferritin was mostly located in LAMP-1-negative structures at all time points studied. The proportion of alpha 2-M-gold containing vesicles strongly labeled for LAMP-1 roughly paralleled the proportion of alpha 2-M-gold-containing structures positive for cytochemically detectable acid phosphatase. Our data indicate that ligands such as transferrin that are internalized through coated pits and receptosomes, but not delivered to lysosomes, do not traverse a lysosomal organelle compartment as marked by LAMP-1 content. Ligands such as alpha 2-M that are destined for lysosomal delivery reach a LAMP-1-positive organelle compartment only after they traverse LAMP-1-negative, non-lysosomal vesicles previously described as receptosomes.