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31.
Interleukin-1-induced leukocyte extravasation across rat mesenteric microvessels is mediated by platelet-activating factor 总被引:6,自引:0,他引:6
Although our understanding of the molecular interactions that mediate the adhesion of leukocytes to venular endothelial cells has greatly expanded, very little is known about the mechanisms that mediate the passage of leukocytes across the vessel wall in vivo. The aim of the present study was to investigate the role of endogenously formed platelet-activating factor (PAF) in the process of leukocyte extravasation induced by interleukin-1 (IL-1). To determine at which stage of emigration PAF was involved, we studied the behavior of leukocytes within rat mesenteric microvessels by intravital microscopy. Rats were injected intraperitoneally with saline, recombinant rat IL-1 beta (IL-1 beta), or the peptide N-formyl-methionyl-leucyl- phenylalanine (FMLP) 4 hours before the exteriorization of the mesenteric tissue. In animals treated with IL-1 beta there was a significant increase in the number of rolling and adherent leukocytes within venules (20- to 40-micron diameter) and in the number of extravasated leukocytes in the tissue. Pretreatment of rats with the PAF receptor antagonist UK-74,505 had no effect on the leukocyte responses of rolling and adhesion, but significantly inhibited the migration of the leukocytes across the vessel wall induced by IL-1 beta (76% inhibition). A structurally unrelated PAF antagonist, WEB-2170, produced the same effect (64% inhibition). However, in contrast, UK- 74,505 had no effect on the leukocyte extravasation induced by FMLP, indicating selectivity for the response elicited by certain mediators. These results provide the first line of direct evidence for the involvement of endogenously formed PAF in the process of leukocyte extravasation induced by IL-1 in vivo. 相似文献
32.
33.
CL Sanchez CS Biskup S Herpertz TJ Gaber CM Kuhn SH Hood FD Zepf 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(10)
The neurotransmitters serotonin and dopamine both have a critical role in the underlying neurobiology of different behaviors. With focus on the interplay between dopamine and serotonin, it has been proposed that dopamine biases behavior towards habitual responding, and with serotonin offsetting this phenomenon and directing the balance toward more flexible, goal-directed responding. The present focus paper stands in close relationship to the publication by Worbe et al. (2015), which deals with the effects of acute tryptophan depletion, a neurodietary physiological method to decrease central nervous serotonin synthesis in humans for a short period of time, on the balance between hypothetical goal-directed and habitual systems. In that research, acute tryptophan depletion challenge administration and a following short-term reduction in central nervous serotonin synthesis were associated with a shift of behavioral performance towards habitual responding, providing further evidence that central nervous serotonin function modulates the balance between goal-directed and stimulus-response habitual systems of behavioral control. In the present focus paper, we discuss the findings by Worbe and colleagues in light of animal experiments as well as clinical implications and discuss potential future avenues for related research. 相似文献
34.
Crosslinking the CD27 antigen on T cells provides a costimulatory signal that, in concert with T-cell receptor crosslinking, can induce T- cell proliferation and cellular immune activation. We find that chronic lymphocytic leukemia (CLL) B cells from most patients coexpress both membrane-bound and soluble CD27, along with its newly identified ligand, CD70. The expression of soluble CD27 may preclude leukemic B cells from stimulating T cells via CD70, thereby potentially impairing their ability to function as effective antigen-presenting cells. We find that leukemic B-cell expression of soluble and membrane-bound CD27 can be downmodulated through a CD40-dependent signal. This signal also induces enhanced expression of CD70 on both normal and leukemic B cells. We find that tumor necrosis factor (TNF)-alpha, or the Th1 cytokine interferon (IFN)-gamma, also can induce downmodulation of CD27, whereas Th2-associated cytokines interleukin-4 (IL-4) or IL-10 can enhance leukemic B-cell expression of this accessory molecule. The modulation of CD27 induced by these conditions is accompanied by reciprocal changes in the expression levels of CD70, suggesting that these accessory molecules may be engaged in reciprocal receptor-ligand downmodulation. Consistent with this, we observe that co-culture of CLL B cells with transfected murine plasmacytoma cells that express human CD70 affects downmodulation of CD27 and enhanced expression of CD70 on leukemic B cells, but does not affect expression of CD27 mRNA. However, we find that CD40-crosslinking, in addition to reducing the level of CD27 protein, also reduces leukemic B-cell expression of CD27 mRNA. This argues that the changes in the expression levels of CD27 following CD40-signaling are not simply due to induced increases in the expression levels of CD70. Finally, we demonstrate that reciprocal changes in expression of CD27 and CD70 may contribute to the enhanced antigen-presenting capacity of CLL B cells after CD40-dependent leukemic B-cell activation. These findings expand the understanding of the regulation of costimulatory molecules important in antigen presentation and also have implications for the immunobiology of and therapy for CLL. 相似文献
35.
13q deletions in lymphoid malignancies 总被引:4,自引:1,他引:4
Liu Y; Hermanson M; Grander D; Merup M; Wu X; Heyman M; Rasool O; Juliusson G; Gahrton G; Detlofsson R 《Blood》1995,86(5):1911-1915
Previous studies have indicated that a candidate tumor suppressor gene resides telomeric of the RB1 gene at 13q14, a region that is commonly deleted in B-cell chronic lymphocytic leukemia (B-CLL). In this study, we have evaluated the frequency and minimal region of overlap for 13q deletions in malignant cells from various lymphoid neoplasms. We observed losses at 13q14 in 33/75 (44%) B-CLL cases, four of 16 (25%) non-Hodgkin's lymphoma (NHL) cases, eight of 29 (28%) patients with acute lymphocytic leukemia (ALL), and one of 15 T-cell lines. In some ALL cases, inactivation of the RB1 gene is suggested as the important event in the 13q deletions. The most commonly deleted marker in CLL and NHL was D13S319, between RBkpt and the D13S25 loci. Homozygous deletions of this marker were observed in 10 of 75 B-CLL cases, in six of which the homozygous deletions included only the D13S319 locus. Our data suggest that 13q deletions are common in lymphoid neoplasms, and that deletion of a candidate tumor suppressor gene(s) in the vicinity of the D13S319 marker is a tumorigenic event in these diseases. 相似文献
36.
Rasool Bagheri Mohammad Reza Pourahmadi Ali Reza Sarmadi Ismail Ebrahimi Takamjani Giti Torkaman Sayyed Hamed Fazeli 《Journal of bodywork and movement therapies》2018,22(2):266-275
Objective
This study aimed to evaluate the effects of kinesiology tape, anesthesia, and kinesiology tape along with anesthesia, on motor neuron excitability.Participants
Participants included 20 healthy men aged 20–35 years, who were examined over 5 sessions.Intervention
The five experimental sessions included: control without applying the kinesiology tape or Eutectic Mixture of Local Anesthetics (EMLA); treatment only with EMLA; only kinesiology tape application; only sham tape application; and treatment with kinesiology tape and EMLA.Main outcome measures
The H-reflex recruitment curve of the soleus and lateral gastrocnemius was recorded by a blinded assessor in the 5 separate sessions randomly assigned with 48 h washout periods. The major H-reflex parameters include: the Hmax/Mmax ratio, the H-reflex threshold stimulation intensity (Hth), the intensity of maximum H-reflex (IntensityHmax), the H-reflex ascending slope (Hslp), and the H-reflex ascending slope fixed into the first three points (first Hslp).Results
The H-reflex parameters (H slope, first Hslp, Hth, and IntensityHmax) were facilitated by application of the kinesiology tape with and without EMLA; however, EMLA inhibited the H-reflex parameters (Hmax/Mmax ratio, Hslp, first Hslp, and Hth) in both the soleus and lateral gastrocnemius. The sham tape did not alter the H-reflex recruitment curve parameters. The statistical model revealed a significant difference between the kinesiology tape and the sham tape and control sessions, between kinesiology tape–EMLA and EMLA, and between kinesiology tape–EMLA and control session.Conclusions
Results suggest that the kinesiology tape facilitates the muscle activity and the underlying mechanism on the gastrosoleus motor neuron pool involves the cutaneous receptors. 相似文献37.
Moiz B Moatter T Hashmi MR Hashmi N Kauser T Nasir A Khurshid M 《Annals of hematology》2008,87(5):385-389
Various hemoglobinopathies have been reported from Pakistan excepting the rare ones like hemoglobin Q India. Our purpose of
study was to identify the mutation (α 1 64 aspartate to histidine) through amplification restriction mutation system-polymerase
chain reaction (ARMS-PCR) in patients where hemoglobin Q has been detected via high performance liquid chromatography (HPLC)
and also to evaluate the cost effectiveness of the two technologies. All patients irrespective of age and gender who underwent
HPLC for identification of their hemoglobin variant during January 1, 2006 to January 30, 2007 were studied. The blood samples
with unknown peak at a retention time of 4.7 min were evaluated at the molecular level. Analysis of HPLC tracings of 11,008
subjects over a thirteen-month period identified ten individuals with hemoglobin Q. Male to female ratio was 1:1.5 and their
age was variable ranging from 1 to 49 (mean 22.8) years. The mean hemoglobin level was 11.3 g/dl while MCV (fl) and MCH (pg)
were 73.0 and 20.8 respectively. HPLC showed an unknown peak of 17.7% which was detected as Hb Q. ARMS based PCR showed Hb
Q specific product of 370 bp and also an amplified product of 766 bp as the control fragment in these samples. This is the
first ever report that documents the presence of Hb Q India (α 64 Asp to His) in Pakistani population. We recommend that HPLC
be used as a useful screening tool especially in developing countries where PCR facilities may not be accessible. 相似文献
38.
Aisha Rasool Fernanda Alvarado-Flores Perrie O'Tierney-Ginn 《Clinical therapeutics》2021,43(2):226-245
PurposeMaternal nutrition is a key modifier of fetal growth and development. However, many maternal diets in the United States do not meet nutritional recommendations. Dietary supplementation is therefore necessary to meet nutritional goals. The effects of many supplements on placental development and function are poorly understood. In this review, we address the therapeutic potential of maternal dietary supplementation on placental development and function in both healthy and complicated pregnancies.MethodsThis is a narrative review of original research articles published between February 1970 and July 2020 on dietary supplements consumed during pregnancy and placental outcomes (including nutrient uptake, metabolism and delivery, as well as growth and efficiency). Impacts of placental changes on fetal outcomes were also reviewed. Both human and animal studies were included.FindingsWe found evidence of a potential therapeutic benefit of several supplements on maternal and fetal outcomes via their placental impacts. Our review supports a role for probiotics as a placental therapeutic, with effects that include improved inflammation and lipid metabolism, which may prevent preterm birth and poor placental efficiency. Supplementation with omega-3 fatty acids (as found in fish oil) during pregnancy tempers the negative effects of maternal obesity but may have little placental impact in healthy lean women. The beneficial effects of choline supplementation on maternal health and fetal growth are largely attributable to its placental impacts. l-arginine supplementation has a potent provascularization effect on the placenta, which may underlie its fetal growth–promoting properties.ImplicationsThe placenta is exquisitely sensitive to dietary supplements. Pregnant women should consult their health care practitioner before continuing or initiating use of a dietary supplement. Because little is known about impacts of many supplements on placental and long-term offspring health, more research is required before robust clinical recommendations can be made. 相似文献
39.
An antibody (DIL) from a patient with idiopathic thrombocytopenic purpura (ITP) was shown to have autospecificity on the basis of reactions with autologous platelets that were identical to those obtained with platelets from normal subjects. DIL antibody also reacted strongly in an immunofluorescence test with platelets from a patient with Glanzmann's thrombasthenia, but failed to react with platelets from a patient with the Bernard-Soulier syndrome who was known to be deficient in glycoprotein Ib (GPIb). Purified GPIb and control platelets, but not Bernard-Soulier platelets, inhibited the lytic activity of DIL. Using the GPIb-specific monoclonal antibody AP1 and one-dimensional rocket electrophoresis into gels containing rabbit antihuman platelet membrane antibody, it was shown that staphylococcal protein A-Sepharose beads coated with DIL antibody selectively remove GPIb from solubilized platelet preparations. By crossed immunoelectrophoresis it was found that DIL recognizes a determinant on GPIb on the membrane side of the cleavage site of the platelet calcium- activated protease (calpain). These studies provide direct evidence for binding of a platelet autoantibody to a determinant on GPIb relatively close to the site of insertion of this protein into the platelet membrane. 相似文献
40.
Yakoob J Rasool S Abbas Z Jafri W Abid S Islam M Ahmad Z 《World journal of gastroenterology : WJG》2008,14(10):1539-1543
AIM: To determine the efficacy of gastric juice polymerase chain reaction (PCR) for the detection of H pylori infection in comparison with histology and gastric antral biopsy PCR in patients on a proton pump inhibitor (PPI). METHODS: Eighty-five consecutive patients with dyspeptic symptoms were enrolled. Gastric biopsies for histology, PCR and gastric juice were collected at endoscopy for PCR of the H pylori urease C gene (ure C). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, positive and negative likelihood ratio for PCR of gastric juice for the H pylori ure C gene was compared to histology and gastric antral biopsy H pylori ure C PCR in patients with and without PPI. RESULTS: Gastric juice PCR was positive in 66 (78%) patients. Histology showed H pylori associated gastritis in 57 (67%). Gastric biopsy PCR was positive in 72 (85%). In patients not taking PPI, the sensitivity, specificity, PPV, NPV, accuracy and positive and negative likelihood ratio for gastric juice PCR were 89%, 72%, 91%, 67%, 90%, 85%, 3.1 and 0.1 respectively. In patients on PPI these values were 86%, 100%%, 100%, 29%, 86%, 9.5 and 1.4, respectively. CONCLUSION: Gastric juice PCR for the diagnosis of H pylori infection has increased sensitivity compared to histology with PPI. The use of gastric juice PCR is recommended to confirm H pylori status in patients taking PPIs. 相似文献