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561.
KS MacDowell JR Caso D Martín-Hernández JL Madrigal JC Leza B García-Bueno 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(3)
Background:
Alterations in the innate immune/inflammatory system have been proposed to underlie the pathophysiology of psychotic disease, but the mechanisms implicated remain elusive. The main agents of the innate immunity are the family of toll-like receptors (TLRs), which detect circulating pathogen-associated molecular patterns and endogenous damage-associated molecular patterns (DAMPS). Current antipsychotics are able to modulate pro- and anti-inflammatory pathways, but their actions on TLRs remain unexplored.Methods:
This study was conducted to elucidate the effects of paliperidone (1mg/Kg i.p.) on acute (6 hours) and chronic (6 hours/day during 21 consecutive days) restraint stress–induced TLR-4 pathway activation and neuroinflammation, and the possible mechanism(s) related (bacterial translocation and/or DAMPs activation). The expression of the elements of a TLR-4-dependent proinflammatory pathway was analyzed at the mRNA and protein levels in prefrontal cortex samples.Results:
Paliperidone pre-treatment prevented TLR-4 activation and neuroinflammation in the prefrontal cortices of stressed rats. Regarding the possible mechanisms implicated, paliperidone regulated stress-induced increased intestinal inflammation and plasma lipopolysaccharide levels. In addition, paliperidone also prevented the activation of the endogenous activators of TLR-4 HSP70 and HGMB-1.Conclusions:
Our results showed a regulatory role of paliperidone on brain TLR-4, which could explain the therapeutic benefits of its use for the treatment of psychotic diseases beyond its effects on dopamine and serotonin neurotransmission. The study of the mechanisms implicated suggests that gut-increased permeability, inflammation, and bacterial translocation of Gram-negative microflora and HSP70 and HGMB1 expression could be potential adjuvant therapeutic targets for the treatment of psychotic and other stress-related psychiatric pathologies. 相似文献562.
Murine thymocytes proliferate in direct response to interleukin-7 总被引:22,自引:2,他引:22
Conlon PJ; Morrissey PJ; Nordan RP; Grabstein KH; Prickett KS; Reed SG; Goodwin R; Cosman D; Namen AE 《Blood》1989,74(4):1368-1373
The ability of interleukin-7 (IL-7) to stimulate murine thymocyte proliferation was investigated. IL-7, either alone or in concert with lectin, induced proliferation of adult thymocytes as well as day 13 fetal and adult CD4-/CD8-thymocytes. The IL-7-induced proliferative response of unfractionated thymocytes could not be inhibited by antibodies to IL-2, or IL-4, IL-6, or the IL-2 receptor. In addition, IL-2, IL-4, and IL-6 were not produced by thymocytes activated with IL- 7, as judged by the absence of biologically active cytokine in IL-7- stimulated culture supernatants. IL-7 could act in concert with IL-2 and IL-4 or with IL-4 to enhance the proliferative response of thymocyte cultures. Thus, IL-7 may cause proliferation of thymocytes directly, not indirectly, through production of IL-2, IL-4, or IL-6. IL- 7 may then play a significant role in differentiation of T lymphocytes. 相似文献
563.
Platelet-activating factor primes neutrophil responses to agonists: role in promoting neutrophil-mediated endothelial damage 总被引:17,自引:0,他引:17
During inflammation polymorphonuclear cells (PMNs) are exposed to agonistic stimuli including activated complement, kallikrein, arachidonic acid metabolites, monokines, and platelet-activating factor (PAF). We report that PAF not only directly activates PMNs but in miniscule quantities (10(-12) mol/L) "primes" them as well, that is, permits PMNs to respond to subsequent stimuli that would be otherwise ineffectual. PAF priming of responses including superoxide generation, elastase release, and aggregation is time dependent and is maximal within five minutes. PAF need not be present during the subsequent exhibition of PMN agonists, but priming is inhibited by cold and is also inhibited by the PAF receptor antagonists BN 52021, L-652, and kadsurenone. An intact PAF molecule is required because lyso-PAF and methoxy-PAF do not prime PMN responses. PAF priming is associated with both enhanced expression of the adhesive glycoprotein identified by OKM- 1 antibody and an enhanced rise in intracellular calcium levels in response to the subsequent addition of agonists such as FMLP. PMNs primed with PAF and stimulated with either F-Met-Leu-Phe or phorbol esters are more effective in lysing and detaching cultured human endothelial cells--damage that can also be inhibited by the PAF antagonists. Because PAF is synthesized and exhibited on surfaces of endothelial cells perturbed by coagulation, we suggest that this lipid may potentiate otherwise trivial activators of marginated PMNs so that they become damaging to the PAF-synthesizing endothelium itself. If so, our studies suggest a possible therapeutic role for PAF inhibitors in excessive inflammatory states. 相似文献
564.
Raghavendra Mohan Rao Nagarathna Raghuram HR Nagendra MR Usharani KS Gopinath Ravi B Diwakar Shekar Patil Ramesh S Bilimagga Nalini Rao 《Indian Journal of Palliative Care》2015,21(2):174-181
Aim:
To compare the effects of yoga program with supportive therapy on self-reported symptoms of depression in breast cancer patients undergoing conventional treatment.Patients and Methods:
Ninety-eight breast cancer patients with stage II and III disease from a cancer center were randomly assigned to receive yoga (n = 45) and supportive therapy (n = 53) over a 24-week period during which they underwent surgery followed by adjuvant radiotherapy (RT) or chemotherapy (CT) or both. The study stoppage criteria was progressive disease rendering the patient bedridden or any physical musculoskeletal injury resulting from intervention or less than 60% attendance to yoga intervention. Subjects underwent yoga intervention for 60 min daily with control group undergoing supportive therapy during their hospital visits. Beck''s Depression Inventory (BDI) and symptom checklist were assessed at baseline, after surgery, before, during, and after RT and six cycles of CT. We used analysis of covariance (intent-to-treat) to study the effects of intervention on depression scores and Pearson correlation analyses to evaluate the bivariate relationships.Results:
A total of 69 participants contributed data to the current analysis (yoga, n = 33, and controls, n = 36). There was 29% attrition in this study. The results suggest an overall decrease in self-reported depression with time in both the groups. There was a significant decrease in depression scores in the yoga group as compared to controls following surgery, RT, and CT (P < 0.01). There was a positive correlation (P < 0.001) between depression scores with symptom severity and distress during surgery, RT, and CT.Conclusion:
The results suggest possible antidepressant effects with yoga intervention in breast cancer patients undergoing conventional treatment. 相似文献565.
Stel HV; Sakariassen KS; Scholte BJ; Veerman EC; van der Kwast TH; de Groot PG; Sixma JJ; van Mourik JA 《Blood》1984,63(6):1408-1415
We have studied the role of factor VIII-von Willebrand factor (FVIII- vWF) in both platelet adherence to subendothelium and ristocetin- induced platelet aggregation using monoclonal antibodies to human FVIII- vWF. Twenty-five monoclonal antibodies were obtained, two of which were directed to the factor VIII moiety of FVIII-vWF; one of these two completely inhibited the procoagulant activity (FVIII:C). The remaining 23 monoclonal antibodies were directed to the von Willebrand factor moiety of FVIII-vWF. The ability of the latter monoclonal antibodies to inhibit platelet adherence to arterial subendothelium was investigated with a perfusion model. According to the number of platelets adhering to the subendothelium, three groups of monoclonal antibodies could be discerned: (A) antibodies not affecting platelet adherence; (B) antibodies that inhibited platelet adherence to the level as observed when von Willebrand's disease plasma was tested; and (C) antibodies that completely inhibited both platelet adherence to subendothelium and ristocetin-induced platelet aggregation. The two antibodies present in group C competed for the same or closely related epitope(s) present on FVIII-vWF. These results demonstrate that a domain is present on the FVIII-vWF molecule that is associated both with ristocetin-induced aggregation and with the ability of FVIII-vWF to support platelet adherence to the subendothelium. Based on these observations, it is concluded that ristocetin-induced binding of FVIII-vWF to platelets reflects, at least in part, a physiologic mechanism regulating the function of FVIII-vWF in primary hemostasis. 相似文献
566.
Raymond SW Tsang Dennis KS Law Shaun D Tyler Gwen S Stephens Mark Bigham Wendell D Zollinger 《The Canadian Journal of Infectious Diseases & Medical Microbiology》2005,16(3):171-174
Three group B Neisseria meningitidis isolates, recovered from meningococcal disease cases in Canada and typed as B:2c:P1.5, were characterized. Multilocus sequence typing showed that all three isolates were related because of an identical sequence type (ST) 573. Isolates typed as 2c:P1.5 are common in serogroup Y meningococci but rare in isolates from serogroups B or C. Although no serogroup Y isolates have been typed as ST-573, eight isolates showed five to six housekeeping gene alleles that were identical to that of ST-573. This suggested that the B:2c:P1.5 isolates may have originated from serogroup Y organisms, possibly by capsule switching.Key Words: Capsule switching, Neisseria meningitidis, Serogroup YNeisseria meningitidis is a significant pathogen that causes invasive meningococcal disease (IMD). The average case fatality rate of 9% to 12% remains high despite the availability of effective antibiotics and vaccines (1). Laboratory study and surveillance of N meningitidis involves the characterization of a number of surface markers of the bacterium, including its capsule and outer membrane proteins (OMPs). Most epidemiological studies of meningococcal disease rely on differentiating meningococcal isolates based on their serogroup, serotype and serosubtype. Serogrouping is determined by the demonstration of serologically distinct epitopes present on chemically and structurally different capsules. Serotyping and serosubtyping rely on the detection of distinct epitopes present on three of five different classes of OMPs of N meningitidis. Serotyping epitopes are found on the class 2 or class 3 OMP (also called PorB) of N meningitidis; these OMPs are expressed in a mutually exclusively manner (ie, a strain will only express either a class 2 or class 3 OMP but not both). Serosubtyping epitopes are present on the class 1 OMP (also called PorA). Based on this nomenclature scheme, a strain can therefore be characterized by its antigenic formula; for example, B:15:P1.7,16 refers to serogroup B, serotype 15 and serosubtype P1.7,16.One of the most important virulence factors of meningococci is the capsular polysaccharide antigen, which is also the basis for serogrouping and is the target antigen for the currently licensed vaccines against A, C, Y and W135 organisms. Of the 13 known serogroups, five (serogroups A, B, C, Y and W135) are responsible for most of the meningococcal disease worldwide (2). In North America, most endemic and epidemic strains belong to serogroups B, C, Y and W135 (3,4). Capsules of serogroups B, C, Y and W135 meningococci contain sialic acid, either as a homopolymer of sialic acids assembled by alpha-2,8 linkages (serogroup B) or alpha-2,9 linkages (serogroup C), or as a heteropolymer of sialic acids with glucose (serogroup Y) or galactose (serogroup W135). Besides demonstrating structural similarities, these four serogroups of meningococci also have very similar capsule polysaccharide synthesis (cps) gene loci (5). Because of this similarity, capsule switching has been demonstrated in vivo and in vitro by specific gene replacement within the cps loci between different serogroups. To date, a number of IMD cases have been described in the literature to be caused by organisms in which capsule switching between serogroup B and C meningococci occurred (6-8).In the present paper, the authors describe three unusual serogroup B meningococci isolated from separate IMD cases in Nanaimo, British Columbia, that presented with the OMP antigens 2c:P1.5, characteristic of serogroup Y strains found in Canada (4). This antigenic profile prompted the authors to examine the relationship of these three serogroup B strains with antigenically similar serogroup Y organisms isolated in Canada. The authors describe the characterization of these antigenically similar isolates and postulate that the B:2c:P1.5 isolates arose by capsule switching from serogroup Y organisms. 相似文献
567.
Structural evidence for a second sialic acid binding site in avian influenza virus neuraminidases
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Joseph N. Varghese Peter M. Colman Albertus van Donkelaar Tony J. Blick Anjali Sahasrabudhe Jennifer L. McKimm-Breschkin 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(22):11808-11812
The x-ray structure of a complex of sialic acid (Neu5Ac) with neuraminidase N9 subtype from A/tern/Australia/G70C/75 influenza virus at 4°C has revealed the location of a second Neu5Ac binding site on the surface of the enzyme. At 18°C, only the enzyme active site contains bound Neu5Ac. Neu5Ac binds in the second site in the chair conformation in a similar way to which it binds to hemagglutinin. The residues that interact with Neu5Ac at this second site are mostly conserved in avian strains, but not in human and swine strains, indicating that it has some as-yet-unknown biological function in birds. 相似文献
568.
569.
Children and adolescents with marginal zone lymphoma have an excellent prognosis with limited chemotherapy or a watch‐and‐wait strategy after complete resection
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Leila Ronceray Oussama Abla Shlomit Barzilai‐Birenboim Simon Bomken Alan KS Chiang Janez Jazbec Edita Kabickova Jelena Lazic Auke Beishuizen Karin Mellgren Fumiko Tanaka Marta Pillon Christine Devalck Marina Gouttenoire Olga Makarova Birgit Burkhardt Andishe Attarbaschi 《Pediatric blood & cancer》2018,65(4)
Data on management of pediatric marginal zone lymphoma (MZL) are scarce. This retrospective study assessed characteristics and outcome in 66 patients who were <18 years old. Forty‐four (67%) had an extranodal MZL (EMZL), 21 (32%) a nodal MZL (NMZL), and one patient a splenic MZL. Thirty‐three patients (50%) received a variable combination of adjuvant chemotherapy/immunotherapy/radiotherapy, while the remainder, including 20 of 21 with NMZL, entered an active observation period. Overall survival was excellent (98 ± 2%), although 11 patients relapsed (17%; NMZL, n = 1; EMZL, n = 10), seven after any therapy and four after complete resection only. In conclusion, outcome of NZML, in particular, seems to be excellent after (in)complete resection and observation only. 相似文献
570.
Suppression of mouse skin tumor promotion and induction of apoptosis in HL-60 cells by Alpinia oxyphylla Miquel (Zingiberaceae) 总被引:3,自引:0,他引:3
There have been considerable efforts to search for naturally occurring
substances for the intervention of carcinogenesis. Many components from
dietary or medicinal plants have been identified that possess substantial
chemopreventive properties. An example is curcumin (Curcuma longa Linn.,
Zingiberaceae), which has been shown to inhibit tumor promotion in
experimental carcinogenesis. Alpinia oxyphylla Miquel, another plant of the
ginger family used in oriental herbal medicine, contains diarylheptanoids
whose structures are analogous to that of curcumin. In the present study,
we have tested A.oxyphylla for its ability to suppress tumor promotion.
Thus, topical application of the methanolic extract of dried fruits of
A.oxyphylla significantly ameliorated 12-O-tetradecanoylphorbol-13-acetate
(TPA)-induced skin tumor promotion as well as ear edema in female ICR mice.
In another study, treatment of HL-60 cells with the methanolic extract of
A.oxyphylla significantly reduced the viability of the cells and also
inhibited DNA synthesis. Microscopic examination of the treated cells
showed characteristic morphology of apoptosis. Furthermore, cells treated
with the extract of A.oxyphylla exhibited internucleosomal DNA
fragmentation in time- and concentration-dependent manners. TPA- stimulated
generation of superoxide anion in differentiated HL-60 cells was also
blunted by A.oxyphylla. Taken together, these findings suggest that
A.oxyphylla possesses potential chemopreventive and antitumorigenic
activities.
相似文献