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951.
Britta M. Ogle Ho Thi Tuyet Hoang Nghia Duyet Nguyen Nhut Xuan Dung 《Economic botany》2003,57(1):103-117
Many of the edible wild plants that are included in local food baskets have both therapeutic and dietary functions. Such medicinal foods have been part of Eastern medicinal theories since ancient times and have recently received attention in the USA and Europe within the fields of functional foods, neutraceuticals and phyto-nutrients. This paper provides an example from Vietnam of the continued use of a multitude of edible wild vegetables. Vietnamese traditional medicine also holds an important position within the health care system and many of the plants that are used have both dietary and medicinal functions. Using a combination of qualitative and quantitative techniques (Rapid Rural Appraisal and Food Frequency Questionnaires), information on over 90 species of edible wild plants was obtained from 4 villages in the Mekong Delta and the Central Highlands. About a third of the plants also had therapeutic roles, forty percent were used also as livestock feeds and one fifth were used as food/livestock feed/ medicine. From a nutrition viewpoint it is important to pay attention to this group of traditional foods for several reasons. Their direct nutritional contribution is often significant but neglected. Very little is known about the health benefits of regular consumption of small quantities of medicinal foods and an important “medicinal role” of traditional plant medicines may be the contribution of small quantities of trace minerals and vitamins. The parallel functions as livestock feeds make animal products more accessible to poor households and help improve the quality of their diets. 相似文献
952.
A nematode collected from Diaprepes abbreviatus is identified and described as a new species, Steinernema diaprepesi n. sp. The new species is closely related to S. feltiae, S. glaseri, and S. oregonense and can be distinguished from these species by the following characteristics: Males: Spicule averaging 79 (71-90) µm and spicule shape; D% (distance from anterior end to excretory pore/ esophagus length × 100) about 80; the ratio SW (spicule length/anal body width) about 1.8. Females: Vulva with short, double- flapped epiptygma; tail terminus usually with 5 papillae-like structures. Infective juveniles: Body averaging 1,002 (880-1,133) µm, EP (distance from anterior end to excretory pore) = 74 (66-83) µm; tail length = 83 (65-91) µm, and E% (EP/tail length × 100) = 89.6 (78-114). Lateral field pattern variable, the formula for the arrangement of ridges from head to tail is: 2, 6, 7, 8, 4, 2. The portion with eight ridges is the longest. This new species can be differentiated further from three closest species (S. feltiae, S. glaseri, and S. oregonense) by characteristic sequences of their ITS regions, including sequence lengths, ratios of similarity, composition, and differences in base characters in sequence alignment. 相似文献
953.
Nef-mediated resistance of human immunodeficiency virus type 1 to antiviral cytotoxic T lymphocytes. 总被引:3,自引:0,他引:3 下载免费PDF全文
Otto O Yang Phuong Thi Nguyen Spyros A Kalams Tanya Dorfman Heinrich G G?ttlinger Sheila Stewart Irvin S Y Chen Steven Threlkeld Bruce D Walker 《Journal of virology》2002,76(4):1626-1631
Although Nef has been proposed to effect the escape of human immunodeficiency virus type 1 (HIV-1) from cytotoxic T lymphocytes (CTL) through downmodulation of major histocompatibility complex class I molecules, little direct data have been presented previously to support this hypothesis. By comparing nef-competent and nef-deleted HIV-1 strains in an in vitro coculture system, we demonstrate that the presence of this viral accessory gene leads to impairment of the ability of HIV-1-specific CTL clones to suppress viral replication. Furthermore, inhibition by genetically modified CTL that do not require major histocompatibility complex class I-presented antigen (expressing the CD4 T-cell receptor [TCR] zeta-chain hybrid receptor) is similar for both nef-competent and -deleted strains, indicating that Nef does not impair the effector functions of CTL but acts at the level of TCR triggering. In contrast, we note that another accessory gene, vpr, does not induce resistance of HIV-1 to suppression by CTL clones. We conclude that Nef (and not Vpr) contributes to functional HIV-1 immune evasion and that this effect is mediated by diminished antigen presentation to CTL. 相似文献
954.
The granulocyte colony-stimulating factor receptor (G-CSFR) regulates the proliferation, differentiation and survival of neutrophilic progenitor cells. In these studies, we introduced mutant G-CSFRs with cytoplasmic domains truncated approximately every 30 amino acids from the C-terminus into interleukin-3 (IL-3)-dependent myeloid LGM-1 cells. The G-CSFR membrane proximal region containing the Box 2 homology sequence was determined to be critical for proliferative signaling, as well as for activation of Janus kinase (JAK2) and p44/42 mitogen-activated protein kinase (MAPK) following G-CSF stimulation. In the presence of increasing concentrations of JAK2 or p44/42 MAPK inhibitors, LGM-1 cells expressing the full-length G-CSFR exhibited a decreased capacity to proliferate in response to G-CSF. These results demonstrate that JAK2 and p44/42 MAPK activation is involved in proliferative signaling through the G-CSFR membrane proximal region containing the Box 2 homology sequence. 相似文献
955.
A self-contained system for the field production of plant recombinant interleukin-10 总被引:4,自引:0,他引:4
Menassa Rima Nguyen Vi Jevnikar Anthony Brandle Jim 《Molecular breeding : new strategies in plant improvement》2001,8(2):177-185
The production of pharmaceutical proteins in plants is creating a broad spectrum of new high-value traits in traditional crop species. As the production of these recombinant proteins moves from bench to field scale, containment and the presence of unwanted secondary metabolites are significant practical issues. We have developed a hybrid male-sterile low-alkaloid tobacco (MSLA) production platform. Recombinant protein is produced in leaves that are harvested prior to flowering. If considered for direct in vivo mammalian use the low-alkaloid background genotype addresses concerns about nicotine, and male sterility further reduces the risk of gene leakage. We have applied this system to the production of human interleukin-10 (phIL-10), a contra-inflammatory cytokine with potential application in the treatment of inflammatory bowel disease and autoimmune diseases. Transgenic low-alkaloid tobacco lines properly assembled a biologically active phIL-10 homodimer. Hybrids made by crossing a single homozygous high-expressing phIL-10 line with a MSLA female were field tested in a high density production system and harvested after 30 days. Recombinant phIL-10 yields were found to be similar in the hybrids and the homozygous control. MSLA tobacco is a practical, self-contained system for the production of plant recombinant proteins. 相似文献
956.
Functionally distinct pools of actin in secretory cells 总被引:5,自引:0,他引:5
Ammar David A.; Nguyen Phuong N. B.; Forte John G. 《American journal of physiology. Cell physiology》2001,281(2):C407
Acid secretion by the gastric parietal cell is controlledthrough movement of vesicles containing the proton pump, theH+-K+-ATPase (HK). We have usedlatrunculin B (Lat B), which binds to monomeric actin, to investigateactin turnover in the stimulated parietal cell. In isolated gastricglands, relatively high concentrations of Lat B were required toinhibit acid accumulation (ED50 ~70 µM). Culturedparietal cells stimulated in the presence of low Lat B (0.1-1µM) have reduced lamellipodia formation and some aberrant punctatephalloidin-stained structures, but translocation of HK and vacuolarswelling appeared unaffected. High Lat B (10-50 µM) resulted ingross changes in actin organization (punctate phalloidin-stainedstructures throughout the cell and nucleus) and reduced translocationof HK and vacuolar swelling. Resting parietal cells treated with highLat B showed minor effects on morphology and F-actin staining. Ifresting cells treated with high Lat B were washed immediately beforestimulation, they exhibited a normal stimulated morphology. These datasuggest distinct pools of parietal cell actin: a pool highlysusceptible to Lat B primarily involved in motile function of culturedcells; and a Lat B-resistant pool, most likely microvillar filaments,that is essential for secretion. Furthermore, the stimulation processappears to accentuate the effects of Lat B, most likely through Lat Bbinding to monomer actin liberated by the turnover of the motile actinfilament pool. 相似文献
957.
Wan Yun Ho Jer-Cherng Chang Kenneth Lim Amaury Cazenave-Gassiot Aivi T. Nguyen Juat Chin Foo Sneha Muralidharan Ashley Viera-Ortiz Sarah J.M. Ong Jin Hui Hor Ira Agrawal Shawn Hoon Olubankole Aladesuyi Arogundade Maria J. Rodriguez Su Min Lim Seung Hyun Kim John Ravits Shi-Yan Ng Markus R. Wenk Edward B. Lee Greg Tucker-Kellogg Shuo-Chien Ling 《The Journal of cell biology》2021,220(9)
958.
Isolation and characterization of monkey interphotoreceptor retinoid-binding protein, a unique extracellular matrix component of the retina 总被引:6,自引:0,他引:6
T M Redmond B Wiggert F A Robey N Y Nguyen M S Lewis L Lee G J Chader 《Biochemistry》1985,24(3):787-793
The interphotoreceptor retinoid-binding protein (IRBP) has been isolated from monkey interphotoreceptor matrix (IPM). Following gentle washing of the IPM from the retinal surface, the protein was purified to homogeneity by concanavalin A-Sepharose affinity chromatography, ion-exchange high-performance liquid chromatography (HPLC), and size-exclusion HPLC. Bovine IRBP was purified similarly and compared with the monkey protein. Sedimentation equilibrium analysis yielded a molecular weight of 106 000 +/- 2900 for the native monkey protein. Sedimentation velocity analysis gave a sedimentation coefficient of 5.4 +/- 0.3 S and a frictional ratio of 1.59, indicating an asymmetrical molecular shape. IRBP contains neutral sugar, including fucose, and sialic acid; the glycoprotein nature of the proteins probably accounts for the microheterogeneity observed in the electrofocusing pattern of both bovine and monkey IRBP. Both IRBPs have isoelectric points between 6.0 and 7.0. The fluorescence emission lambda max of the bound ligand was 470 nm with excitation at 340 nm, while the excitation lambda max was 333 nm with emission at 470 nm, for monkey IRBP incubated with exogenous all-trans-retinol. The amino acid compositions of the monkey and bovine proteins are similar; nonpolar amino acids account for over 50% of the residues, which may explain the apparent hydrophobic nature of the isolated proteins. The amino-terminal analyses indicated considerable homology between the monkey and bovine IRBPs in this region and verified the purity of the isolated proteins. IRBP thus appears to be a unique, conserved glycoprotein of the retinal extracellular matrix that could serve as a retinoid-transport vehicle. 相似文献
959.
101 species of oribatid mites and 12 species of helminths--anoplocephalids, transmitted by these mites, were found out by Soviet-Vietnam studies in agroecosystems and tropical forests of northern and southern Vietnam. Helminths were recorded from graminivorous mammals as follows: horses, zebu, sheep, goats, buffaloes, deer, hares, elephant, 2 species of rates, 5 species of monkeys and 11 species of birds. 相似文献
960.
Parasternal intercostal muscle remodeling in severe chronic obstructive pulmonary disease. 总被引:1,自引:0,他引:1
Sanford Levine Taitan Nguyen Michael Friscia Jianliang Zhu Wilson Szeto John C Kucharczuk Boris A Tikunov Neal A Rubinstein Larry R Kaiser Joseph B Shrager 《Journal of applied physiology》2006,101(5):1297-1302
Studies in experimental animals indicate that chronic increases in neural drive to limb muscles elicit a fast-to-slow transformation of fiber-type proportions and myofibrillar proteins. Since neural drive to the parasternal intercostal muscles (parasternals) is chronically increased in patients with severe chronic obstructive pulmonary diseases (COPDs), we carried out the present study to test the hypothesis that the parasternals of COPD patients exhibit an increase in the proportions of both slow fibers and slow myosin heavy chains (MHCs). Accordingly, we obtained full thickness parasternal muscle biopsies from the third interspace of seven COPD patients (mean +/- SE age: 59 +/- 4 yr) and seven age-matched controls (AMCs). Fiber typing was done by immunohistochemistry, and MHC proportions were determined by SDS-PAGE followed by densitometry. COPD patients exhibited higher proportions of slow fibers than AMCs (73 +/- 4 vs. 51 +/- 3%; P < 0.01). Additionally, COPD patients exhibited higher proportions of slow MHC than AMCs (56 +/- 4 vs. 46 +/- 4%, P < 0.04). We conclude that the parasternal muscles of patients with severe COPD exhibit a fast-to-slow transformation in both fiber-type and MHC proportions. Previous workers have demonstrated that remodeling of the external intercostals, another rib cage inspiratory muscle, elicited by severe COPD is characterized by a slow-to-fast transformation in both fiber types and MHC isoform proportions. The physiological significance of this difference in remodeling between these two inspiratory rib cage muscles remains to be elucidated. 相似文献