Evaluation of GABA Production and Probiotic Activities of Enterococcus faecium BS5

Probiotics and Antimicrobial Proteins - Gamma-aminobutyric acid (GABA) is a principal inhibitory neurotransmitter in the central nervous system and is produced by irreversible decarboxylation of...     

Control of Globodera tabacum solanacearum by Alternating Host Resistance and Nematicide

The feasibility of alternating use of resistant vs. susceptible flue-cured tobacco cultivars to improve control of Globodera tabacum subsp, solanacearum (TCN) was investigated at two Virginia locations in 1984-86. Post-harvest TCN population densities were reduced in each year of the study when fenamiphos was used with a TCN-resistant cultivar (NC 567), relative to susceptible cultivars (K 326 or Mc 944). Using NC 567 with fenamipbos also reduced preplant TCN population densities in the next growing season. Egg population densities before planting in 1986 were significantly lower in plots planted with NC 567 in 1984, even when a susceptible cultivar had been planted in 1985. Use of fenamiphos with NC 567 in 1984 and 1985 further reduced preplant egg population densities in 1986. Economic returns were significantly greater in 1984 when NC 567 was used with fenamiphos, rather than a susceptible cultivar. Treatments involving fenamiphos and (or) NC 567 in 1984 and 1985 resulted in higher economic returns in 1986 than did treatments using a susceptible cultivar without fenamiphos in both previous years. Economic returns were highest in 1986 when fenamiphos and NC 567 were used in 1984 and 1985 and a susceptible cultivar was planted in 1986.     

Semaphorin 3B is a 1,25-Dihydroxyvitamin D3-induced gene in osteoblasts that promotes osteoclastogenesis and induces osteopenia in mice

The vitamin D endocrine system is important for skeletal homeostasis. 1,25-Dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] impacts bone indirectly by promoting intestinal absorption of calcium and phosphate and directly by acting on osteoblasts and osteoclasts. Despite the direct actions of 1,25(OH)(2)D(3) in bone, relatively little is known of the mechanisms or target genes that are regulated by 1,25(OH)(2)D(3) in skeletal cells. Here, we identify semaphorin 3B (SEMA3B) as a 1,25(OH)(2)D(3)-stimulated gene in osteoblastic cells. Northern analysis revealed strong induction of SEMA3B mRNA by 1,25(OH)(2)D(3) in MG-63, ST-2, MC3T3, and primary osteoblastic cells. Moreover, differentiation of these osteogenic cells enhanced SEMA3B gene expression. Biological effects of SEMA3B in the skeletal system have not been reported. Here, we show that osteoblast-derived SEMA3B alters global skeletal homeostasis in intact animals and osteoblast function in cell culture. Osteoblast-targeted expression of SEMA3B in mice resulted in reduced bone mineral density and aberrant trabecular structure compared with nontransgenic littermates. Histomorphometry studies indicated that this was likely due to increased osteoclast numbers and activity. Indeed, primary osteoblasts obtained from SEMA3B transgenic mice stimulated osteoclastogenesis to a greater extent than nontransgenic osteoblasts. This study establishes that SEMA3B is a 1,25(OH)(2)D(3)-induced gene in osteoblasts and that osteoblast-derived SEMA3B impacts skeletal biology in vitro and in vivo. Collectively, these studies support a putative role for SEMA3B as an osteoblast protein that regulates bone mass and skeletal homeostasis.