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1.
Gokhlesh Kumar Subhodeep Sarker Simon Menanteau-Ledouble Mansour El-Matbouli 《Parasitology research》2015,114(6):2301-2308
2.
Control of pollen hydration in Brassica requires continued protein synthesis, and glycosylation in necessary for intraspecific incompatibility 总被引:3,自引:1,他引:2
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Sarker RH Elleman CJ Dickinson HG 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(12):4340-4344
Pollen hydration and self-incompatibility (SI) in Brassica have been studied by using a combination of in vivo video-microscopy and experiments with metabolic inhibitors. Experiments with cycloheximide confirm earlier observations that pollen hydration is regulated through protein synthesis. No protein or glycoprotein has positively been identified with this event; however, it is unlikely that the total pool of any particular glycoprotein is involved, but rather a newly synthesized or otherwise activated fraction. Micromanipulation of pollen on the stigmatic papillae suggests that access to this hydration regulation system is limited to members of the Brassicaceae: pollen grains of other species—even those possessing dry stigmas—fail to hydrate. It is proposed that an interaction between enzymes of the stigma surface and the superficial layer of the pollen grain coating creates continuity between the content of the papillar wall and the grain protoplast. Inhibition of protein synthesis also overcomes SI, and since the advent of regulated hydration and synthesis of the so-called S-gene glycoproteins coincide with the acquisition of the SI system, there is strong circumstantial evidence that the same molecular species is involved in both processes. Experiments with tunicamycin, which prevents glycosylation of glycoproteins, indicate that the glycosyl groups of the S-gene glycoprotein are required for the operation of the SI system but not for the regulation of hydration. Further experiments suggest that pollen is positively inhibited on incompatible papillae but that this inhibition is biostatic. Recovery from the effects of the SI system appears to involve the metabolism of an inhibitor by the pollen. SI in Brassica thus emerges as a sophisticated process under dynamic control in both the female and male partners. The evolutionary advantages of such a system are discussed. 相似文献
3.
T Azim R C Halder M S Sarker S Ahmed J Hamadani A Chowdhury F Qadri M A Salam R B Sack M J Albert 《Clinical and Vaccine Immunology : CVI》1995,2(4):492-495
The pathogenesis of the systemic complications, leukemoid reaction and hemolytic uremic syndrome, associated with Shigella dysenteriae type 1 infection is not well understood. The excessive production of proinflammatory cytokines, including tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6), has been suggested as a possible factor. We measured IL-6 and TNF-alpha in stools of 56 children with S. dysenteriae 1 infection and 29 children without any apparent infection, all age 12 to 60 months. Sixteen children with S. dysenteriae 1 infection had leukemoid reaction or hemolytic uremic syndrome (complicated shigellosis), while the others did not (uncomplicated shigellosis). Stool IL-6 and TNF-alpha concentrations were higher in children with uncomplicated shigellosis than in children with complicated shigellosis (P = 0.009 and < 0.001, respectively) or in uninfected children (P < 0.001). It is concluded that complicated infection is not associated with higher concentrations of the proinflammatory cytokines IL-6 and TNF-alpha in stool. 相似文献
4.
A B Sarker T Akagi T Yoshino Y Hoshida K Takahashi Y Horie 《Acta pathologica japonica》1990,40(8):581-587
Immunoreactivity with monoclonal antibodies against the intermediate filament protein, vimentin, and epithelial membrane antigen (EMA) was examined in 330 cases of lymphoma (317 non-Hodgkin's and 13 Hodgkin's lymphomas), 12 reactive lymph nodes and mononuclear cells of the peripheral blood using either indirect immunoperoxidase staining or the avidin-biotin immunoperoxidase complex technique. The cell origin of each tumor was established using a panel of monoclonal antibodies against lymphocyte differentiation antigens. There were 41 T-cell, 247 B-cell and 29 undetermined lymphomas, and 13 cases of Hodgkin's disease in the series. Vimentin was expressed in 24 T-cell lymphomas (58.5%) and 60 B-cell lymphomas (24.2%). This difference in frequency was statistically significant. Vimentin expression in follicular lymphomas was less frequent than in diffuse B-cell lymphomas. In diffuse lymphomas, small and medium cell types were more reactive with anti-vimentin than large cell types. Reed-Sternberg cells (R-S cells) in Hodgkin's disease were positive for vimentin in 11 cases (84.6%). The frequency of EMA reactivity in lymphomas was low, particularly in T-cell lymphomas. No positive cases were found among follicular lymphomas. In diffuse non-Hodgkin's lymphomas, EMA was expressed only in mixed and large cell types, but never in smaller ones. In conclusion, monoclonal antibodies against vimentin and EMA appear to be of limited usefulness for the diagnosis of non-Hodgkin's lymphomas, but anti-vimentin antibody may be used as an adjunct to the diagnosis of R-S cells in Hodgkin's disease. 相似文献
5.
We studied the binding patterns of 14 lectins in human normal and cirrhotic liver (LC) tissues and hepatocellular carcinomas (HCC) using the ABC method. Lectins were divided into 4 groups according to their binding patterns in normal tissues: (A) PHA, MPA, LcH, RCA-I, and WGA, which bound to hepatocytes and all three types of sinusoidal cells; (B) BPA, GS-I, PNA, and SBA, which bound to Kupffer cells and endothelia of interlobular arteries and veins and bile duct epithelia in the portal tract, but not to hepatocytes; (C) UEA-I, which bound only to endothelia of interlobular arteries and veins and bile duct epithelia in the portal tract; (D) LBA, Lotus, LPA, and SJA, which showed no binding. Thus group B lectins may be useful markers of Kupffer cells. Only electron microscopic examination revealed the precise binding sites of lectins in sinusoidal cells and hepatocytes. Hepatocyte cell surface polarities demonstrated by lectin binding in LC and HCC were different from those in the normal liver. The binding pattern of PHA to LC hepatocytes changed from a membranous to both a membranous and a cytoplasmic pattern, and that of LcH to HCC cells changed to dot-like staining in the cytoplasm. These changes of polarities in LC and HCC might be caused by changes in the distribution of lectin-binding carbohydrates or by the altered glycosylation of glycoconjugates. 相似文献
6.
To determine if the cellular factors La autoantigen (La) and polypyrimidine tract-binding protein (PTB) are required for hepatitis C virus (HCV) replication, we used siRNAs to silence these factors and then monitored their effect on HCV replication using quantitative RT-PCR. In addition, we determined the influence of PTB on the activity of the 3' noncoding region (NCR) of HCV and investigated its interaction with the components of the HCV replicase complex. We found that La is essential for efficient HCV replication while PTB appears to partially repress replication. PTB does, however, block the binding of HCV RNA-dependent RNA polymerase (RdRp, NS5B) to the 3'NCR. Indirect immunofluorescence microscopy showed co-localization of cytoplasmic PTB with the HCV RdRp in hepatoma cells (Huh-7) expressing HCV proteins, while in vitro translation of viral proteins from the HCV replicon revealed the interaction of PTB isoforms with NS5B polymerase and NS3. 相似文献
7.
Three studies were conducted to determine the effects of reproductive condition and hormonal background on the acquisition and retention of a prior maternal experience. In the first study five experience conditions were compared. All animals gave birth and received either no postpartum contact with pups or 1/2 hr, 1 hr, 2 hr or 24 hr of pup contact and were tested for maternal behavior 10 days later. Animals receiving pregnancy and parturitional experience, but minimal social experience with young, exhibited significantly longer maternal onset latencies than did groups receiving 2 or 24 hr of prior experience; also, comparisons of 10- and 30-day retention intervals indicated that animals tested 10 days after a 24-hr experience exhibited shorter latencies than those tested 30 days later. Thus, the duration of the postpartum experience and the interval since prior experience both affect the level of maternal responsiveness shown. In the second study six groups of females were tested. Four groups were permitted one day of interaction with pups either after parturition (primiparous animals) or following pup induction procedures (nulliparous animals) and were tested for their maternal responsiveness to foster pups 25-35 days later, either on day 19 of a subsequent pregnancy or following resumption of estrous cycling. For most measures of maternal behavior there were significant main experience and test effects; experienced and pregnant animals exhibited shorter latencies to retrieve, lick and crouch over pups than did inexperienced and cycling animals, respectively. Significant interactions were also found for genital licking latency as well as for retrieval and crouch frequencies.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
8.
Dipankar Das Kasturi Bhattacharjee Sumita Sarma Barthakur Prerana Sushil Tahiliani Panna Deka Harsha Bhattacharjee Apurba Deka Rajashree Paul 《Indian journal of ophthalmology》2014,62(5):638-641
Retinoblastoma, the most common primary malignant intraocular tumor of childhood is a great success story in pediatric and ocular oncology. Pathology of retinoblastoma is important to guide the treatment modalities. Differentiated retinoblastoma is commonly seen in younger age group. Since a hundred years, we have been observing two typical true rosettes in retinoblastoma in the form of Flexner-Wintersteiner (FW) and Homer Wright (HW) rosettes and in many occasions pseudorosettes have been documented. In the present case report, a third new type of rosette was identified in a differentiated retinoblastoma which had an unusual anterior segment involvement. 相似文献
9.
10.
Opal SM Palardy JE Chen WH Parejo NA Bhattacharjee AK Cross AS 《The Journal of infectious diseases》2005,192(12):2074-2080
BACKGROUND: An experimental vaccine for sepsis, composed of detoxified Escherichia coli J5 lipopolysaccharide (LPS) complexed with the outer membrane protein (OMP) of Neisseria meningitidis group B, induces anti-core glycolipid antibody and has been tested in pilot studies in human volunteers. METHODS: Mice were immunized with the LPS-J5/OMP vaccine with or without synthetic oligodeoxynucleotides (ODNs) containing unmethylated CpG motifs as a vaccine adjuvant (CpG ODN). The efficacy of the vaccine-induced antibody response was tested in a cecal ligation and puncture model. RESULTS: Immunization resulted in a >20-fold increase in anti-core glycolipid antibody levels, which were further increased 5-fold by the addition of CpG ODN, compared with the levels in mice in the control group. The vaccine provided a survival advantage after a cecal ligation and puncture was performed (P < .01) and significantly decreased the levels of bacteria in organs. Immunoglobulin G (IgG) anti-core glycolipid antibodies were decreased in mice to a significantly greater extent than were levels of total circulating IgG or IgG to the OMP part of the vaccine complex, suggesting specific epitope binding and clearance. CONCLUSIONS: These results indicate that the detoxified LPS-J5/OMP vaccine induces high levels of antibody against the core glycolipid of LPS and functions in vivo to promote clearance of gram-negative bacteria and improve the outcome of experimental polymicrobial intra-abdominal sepsis. 相似文献