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161.
The aim of this paper was to show the potential of Salmonella enteritidis infection to eventually result in visual impairment. A case of salmonellosis in a 6-year-old boy, caused by intake of a cake made from eggs infected with Salmonella enteritidis, is presented. Prolonged duration of the disease was followed by complete remission of neurologic complications and persistent amaurosis with bilateral optic nerve atrophy. A severe form of Salmonella enterocolitis with neurologic involvement can lead to optic nerve lesion with consequential loss of vision. 相似文献
162.
Major glycolipids [monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG), sulfoquinovosyldiacylglycerol (SQDG)) and phospholipids (phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylglycerol (PG)] as well as betaine lipid 1,2-diacylglycero-O-4'-(N,N,N-tri-methyl)-homoserine (DGTS) were isolated from Anfeltia tobuchiensis (Rhodophyta), Laminaria japonica, Sargassum pallidum (Phaeophyta), Ulva fenestrata (Chlorophyta) and Zostera marina (Embriophyta), harvested in the Sea of Japan. GC analysis of their fatty acid (FA) composition revealed that the n-6 polyunsaturated FAs (PUFAs) shared the most part of the sum of n-6 and n-3 PUFAs in PC and PE compared with glycolipids and PG. In algae, it was related to the prevalence of 20:4n-6 over 20:5n-3 in non-photosynthetic lipids. Percentage of n-6 PUFAs as well as the sum of n-3 and n-6 PUFAs decreased in the following sequence: PC-->PE-->PG. The saturation increased in the lines of MGDG-->DGDG-->SQDG and PC-->PE-->PG. PG was close to SQDG by the level of saturation. Distribution of C(18) and C(20) PUFAs in polar lipids depended on taxonomic position of macrophytes. Balance between C(18) and C(20) PUFAs was preferably shifted to the side of C(20) PUFAs in PC and PE that was observed in contrast to glycolipids and PG from L. japonica containing both series of FAs. The set of major FAs of polar lipid classes can essentially differ from each other and from total lipids of macrophytes. For example, MGDG was found to accumulate characteristic fatty acids 16:4n-3, 16:3n-3, 18:3n-6 and 18:4n-3, 20:3n-6 in U. fenestrata, Z. marina, L. japonica and S. pallidum, respectively. 相似文献
163.
Effects of Cr(VI) long-term and low-dose action on mammalian antioxidant enzymes (an in vitro study)
Asatiani N Sapojnikova N Abuladze M Kartvelishvili T Kulikova N Kiziria E Namchevadze E Holman HY 《Journal of inorganic biochemistry》2004,98(3):490-496
In order to investigate the low-dose long-term Cr(VI) action on antioxidant enzymes in cultured mammalian cells we estimated the activity of glutathione dependent antioxidant enzymes, catalase and superoxide dismutase (SOD) under various chromium concentrations in human epithelial-like L-41 cells. The long-term action of 20 microM causes the toxicity that results in losing of the cell viability by activating the apoptotic process, as identified by morphological analysis, the activation of caspase-3, and DNA fragmentation. The toxic chromium concentration totally destroys glutathione antioxidant system, and diminishes the activity of catalase and cytosolic Cu, ZnSOD. The non-toxic concentration (2 microM) causes the activation of the antioxidant defense systems, and they neutralize the oxidative impact. 相似文献
164.
Eikelis N Lambert G Wiesner G Kaye D Schlaich M Morris M Hastings J Socratous F Esler M 《American journal of physiology. Endocrinology and metabolism》2004,286(5):E744-E752
The link between the human sympathoadrenalmedullary system and the adipocyte hormone leptin is controversial. We measured total and regional norepinephrine spillover, epinephrine secretion rate, and extra-adipocyte leptin release in 22 lean [body mass index (BMI) < 26] and 20 obese (BMI > 28) normotensive men who underwent arterial and central venous catheterization. Because plasma clearance of leptin is primarily by renal removal, for men at steady state we could estimate whole body leptin release to plasma from renal plasma leptin extraction. Whole body leptin release was 1,950 +/- 643 (means +/- SE) ng/min in obese men and 382 +/- 124 ng/min in lean men (P < 0.05). Total and renal norepinephrine spillover rates correlated directly with whole body leptin secretion rate. Leptin is released from multiple nonadipocyte sites, which we tested by use of simultaneous arteriovenous blood sampling. We found a surprisingly large contribution of brain leptin release to the plasma leptin pool, 529 +/- 175 ng/min (> 40% whole body leptin release), with greater leptin release in obese than in lean men, 935 +/- 321 vs. 160 +/- 59 ng/min (P = 0.045). In parallel with leptin measurements, we also quantified brain serotonin turnover and jugular overflow of neuropeptide Y (NPY). Brain serotonin turnover was higher in obese than in lean men, 227 +/- 112 vs. 21 +/- 14 ng/min (P = 0.019), as was overflow of NPY from the brain, 12.9 +/- 1.4 vs. 5.3 +/- 2.2 ng/min (P = 0.042). These results suggest that leptin is released within the brain and at an increased rate in obese humans, in whom activation of brain serotonergic and NPY mechanisms also exists. 相似文献
165.
Women who are at increased risk of developing ovarian cancer because of their family history may need to make decisions about the medical management of their cancer risk--whether to have ovarian screening or undergo prophylactic surgery. This qualitative study explores the perceived physical and emotional implications of undergoing preventative surgery using data collected during interviews with 23 high-risk premenopausal women who had undergone prophylactic oophorectomy because of their family history of cancer. Despite the fact that all of these women regarded their decision to undergo surgery extremely positively, 20 women also described what they regarded as the costs of undergoing surgery. These included post-operative complications, the onset of menopausal symptoms, side effects of hormone replacement therapy, and negative effects on body image and gender identity. The perceived benefits of surgery were described as risk reduction, enabling one to fulfil family obligations, removing the need for gynecological screening, cessation of menstruation, and positive side effects of hormone replacement therapy. This study suggests there is a need to inform women about potential physical and emotional sequelae of oophorectomy prior to undergoing this procedure. 相似文献
166.
Stewart SG Bausek N Wohlrab F Schneider WJ Janet Horrocks A Wishart GJ 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2004,137(4):657-663
The interaction of chicken spermatozoa with the inner perivitelline layer from different avian species in vitro during a 5 min co-incubation was measured as the number of points of hydrolysis produced per unit area of inner perivitelline layer. The average degree of interaction, as a proportion of that between chicken spermatozoa and their homologous inner perivitelline layer, was: equal to or greater than 100% within Galliformes (chicken, turkey, quail, pheasant, peafowl and guineafowl); 44% within Anseriformes (goose, duck); and less than 30% in Passeriformes (Zebra Finch) and Columbiformes (collared-dove). The homologue of the putative chicken sperm-binding proteins, chicken ZP1 and ZP3, were identified by Western blotting with anti-chicken ZP1/ZP3 antibody in the perivitelline layers of all species. The functional cross-reactivity between chicken spermatozoa and heterologous inner perivitelline layer appeared to be linked to known phylogenetic distance between the species, although it was not related to the relative affinity of the different ZP3 homologues for anti-chicken ZP3. This work demonstrates that sperm interaction with the egg investment does not represent such a stringent species-specific barrier in birds as it does in mammals and marine invertebrates. This may be a factor in the frequency of hybrid production in birds. 相似文献
167.
Carepo MS Azevedo JS Porto JI Bentes-Sousa AR Batista Jda S Silva AL Schneider MP 《Genetics and molecular research : GMR》2004,3(1):181-194
Chromobacterium violaceum is a Gram-negative bacterium found in a wide variety of tropical and subtropical ecosystems. The complete genome sequence of C. violaceum ATCC 12472 is now available, and it has considerable biotechnological potential for various applications, such as environmental detoxification, as well as medical and agricultural use. We examined the biotechnological potential of C. violaceum for environmental detoxification. Three operons, comprising the ars operon, involved in arsenic resistance, the cyn operon, involved in cyanate detoxification, and the hcn operon, encoding a cyanase, responsible for biogenic production of cyanide, as well as an open reading frame, encoding an acid dehalogenase, were analyzed in detail. Probable catalytic mechanisms for the enzymes were determined, based on amino acid sequence comparisons and on published structural information for these types of proteins. 相似文献
168.
Model of angiogenesis in mice with severe combined immunodeficiency (SCID) and xenoengrafted with Epstein-Barr virus-transformed B cells 总被引:1,自引:0,他引:1
Xenoengraftment of human cells in mice with severe combined immunodeficiency (SCID) has been used as a model system to study the mechanisms of B-cell lymphomagenesis. In the study reported here, we determined that SCID mice can also be used as a model to study angiogenesis in B-cell lymphomas. The C.B-17 scid/scid mice were xenotransplanted with Epstein-Barr virus (EBV)-transformed lymphoblastoid cell lines (LCL), and we determined whether CD31, a marker found on endothelial cells, was detected in the human B-cell lymphomas that developed in these mice. Microvessel formation was identified by use of immunohistochemical staining for CD31. To assess possible mechanisms of angiogenic stimulus, we analyzed the expression of interleukin 8 (IL-8), a chemokine documented to promote angiogenesis, in non-small-cell lung cancer and bronchogenic carcinomas. We observed that a panel of LCL and LCL-lymphomas expressed IL-8 mRNA and protein. Neutralization of IL-8, however, did not inhibit lymphomagenesis, suggesting that IL-8 is not essential for angiogenesis in this model. To examine other parameters of angiogenesis, we identified expression of vascular endothelial growth factor in the lymphomas. These data suggest that angiogenesis accompanies EBV-associated B-cell lymphoma development, but IL-8 is not essential for this process. Thus, the SCID mouse model is amenable to testing of anti-angiogenic factors. 相似文献
169.
Gruden K Kuipers AG Guncar G Slapar N Strukelj B Jongsma MA 《Insect biochemistry and molecular biology》2004,34(4):365-375
Potato synthesises high levels of proteinase inhibitors in response to insect attack. This can adversely affect protein digestion in the insects, leading to reduced growth, delayed development and lowered fecundity. Colorado potato beetle overcomes this defence mechanism by changing the composition of its digestive proteinases. The induced cysteine proteinases in the adapted gut sustain a normal rate of protein hydrolysis either by inactivating the inhibitors by cleavage or by insensitivity to the inhibitors as a result of high Kis. In this study cDNA clones of cysteine proteinases in adapted guts were isolated by nested PCR on the basis of N-terminal sequences previously determined for purified enzymes (Gruden et al., 2003). The cysteine proteinase cDNAs can be classified into three groups: intestains A, B and C. The amino acid identity is more than 91% within and 35-62% between the groups. They share 43-50% identity to mammalian cathepsins S, L, K, H, J and cathepsin-like enzymes from different arthropods. Homology modelling predicts that intestains A, B and C follow the general fold of papain-like proteinases. Intestains from each group, however, differ in some specific structural characteristics in the S1 and S2 binding sites that could influence enzyme-inhibitor interaction and thus, provide different mechanisms of resistance to inhibitors for the different enzymes. Gene expression analysis revealed that the intestains A and C, but not B, are induced twofold by potato plants with high levels of proteinase inhibitors. 相似文献
170.
Wong SS Sun NN Lantz RC Witten ML 《American journal of physiology. Lung cellular and molecular physiology》2004,287(4):L859-L866
To characterize the tachykininergic effects in fire smoke (FS)-induced acute respiratory distress syndrome (ARDS), we designed a series of studies in rats. Initially, 20 min of FS inhalation induced a significant increase of substance P (SP) in bronchoalveolar lavage fluid (BALF) at 1 h and persisted for 24 h after insult. Conversely, FS disrupted 51.4, 55.6, 46.3, and 43.0% enzymatic activity of neutral endopeptidase (NEP, a primary hydrolyzing enzyme for SP) 1, 6, 12, and 24 h after insult, respectively. Immunolabeling density of NEP in the airway epithelium largely disappeared 1 h after insult due to acute cell damage and shedding. These changes were also accompanied by extensive influx of albumin and granulocytes/lymphocytes in BALF. Furthermore, levels of BALF SP and tissue NEP activity dose dependently increased and decreased, respectively, following 0, low (10 min), and high (20 min) levels of FS inhalation. However, neither the time-course nor the dose-response study observed a significant change in the highest affinity neurokinin-1 receptor (NK-1R) for SP. Finally, treatment (10 mg/kg im) with SR-140333B, an NK-1R antagonist, significantly prevented 20-min FS-induced hypoxemia and pulmonary edema 24 h after insult. Further examination indicated that SR-140333B (1.0 or 10.0 mg/kg im) fully abolished early (1 h) plasma extravasation following FS. Collectively, these findings suggest that a combination of sustained SP and NEP inactivity induces an exaggerated neurogenic inflammation mediated by NK-1R, which may lead to an uncontrolled influx of protein-rich edema fluid and cells into the alveoli as a consequence of increased vascular permeability. 相似文献