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51.
Di Iorio B Cirillo M Bellizzi V Stellato D De Santo NG;Campania Dialysis Registry Research Group 《The International journal of artificial organs》2007,30(4):325-333
BACKGROUND: This study investigated prevalence and correlates of anemia and uncontrolled anemia in chronic hemodialysis patients. METHODS: A cross-sectional analysis was performed on registry data for 2,746 chronic (>6 months) hemodialysis patients aged 25-84. Data collection included years of dialysis, hours of dialysis/wk, disease causing hemodialysis, body mass index (BMI), erythropoietin (EPO) treatment, hemoglobin, markers of viral hepatitis, serum albumin, calcium, and phosphorus. RESULTS: Prevalence was 88.7% for anemia (hemoglobin <11 g/100 mL and EPO treatment at any Hb level), 39.4% for uncontrolled anemia (hemoglobin<11 g/100 mL). Gender, years of dialysis, hereditary cystic kidney disease (HCKD), and low BMI (<24 kg/m2) were independent correlates of anemia (P<0.001). Gender, HCKD, low BMI, serum albumin and calcium were independent correlates of uncontrolled anemia (P<0.05). An interaction was found between age (not correlated with anemia and uncontrolled anemia) and the association of gender with uncontrolled anemia (P<0.05). EPO doses were higher in patients with high prevalence of uncontrolled anemia than in patients with low prevalence (i.e., women vs men, other diseases vs HCKD, low vs not-low BMI, P<0.01). Gender, years of dialysis, HCKD, BMI, serum albumin, and calcium were independent correlates of the hemoglobin/EPO dose ratio in patients on EPO treatment (P<0.05). CONCLUSION: Anemia and uncontrolled anemia are more frequent in hemodialysis patients with shortterm dialysis, diseases other than HCKD, low BMI, and female gender. Gender effect was lower in elderly patients. Uncontrolled anemia was also associated with low serum albumin and calcium, suggesting that these parameters are indices of EPO resistance. 相似文献
52.
Cryptosporidiosis is an important diarrheal disease of humans and neonatal livestock caused by Cryptosporidium spp. that infect epithelial cells. Recovery from Cryptosporidium parvum infection in adult hosts involves CD4(+) T cells with a strong Th1 component, but mechanisms of immunity in neonates are not well characterized. In the present investigation with newborn mice, similar acute patterns of infection were obtained in C57BL/6 wild-type (WT) and T and B cell-deficient Rag2(-/-) mice. In comparison with uninfected controls, the proportion of intestinal CD4(+) or CD8(+) T cells did not increase in infected WT mice during recovery from infection. Furthermore, infection in neonatal WT mice depleted of CD4(+) T cells was not exacerbated. Ten weeks after WT and Rag2(-/-) mice had been infected as neonates, no patent infections could be detected. Treatment at this stage with the immunosuppressive drug dexamethasone produced patent infections in Rag2(-/-) mice but not WT mice. Expression of inflammatory markers, including gamma interferon (IFN-γ) and interleukin-12p40 (IL-12p40), was higher in neonatal WT mice than in Rag2(-/-) mice around the peak of infection, but IL-10 expression was also higher in WT mice. These results suggest that although CD4(+) T cells may be important for elimination of C. parvum, these cells are dispensable for controlling the early acute phase of infection in neonates. 相似文献
53.
Sawa S Lochner M Satoh-Takayama N Dulauroy S Bérard M Kleinschek M Cua D Di Santo JP Eberl G 《Nature immunology》2011,12(4):320-326
Lymphoid cells that express the nuclear hormone receptor RORγt are involved in containment of the large intestinal microbiota and defense against pathogens through the production of interleukin 17 (IL-17) and IL-22. They include adaptive IL-17-producing helper T cells (T(H)17 cells), as well as innate lymphoid cells (ILCs) such as lymphoid tissue-inducer (LTi) cells and IL-22-producing NKp46+ cells. Here we show that in contrast to T(H)17 cells, both types of RORγt+ ILCs constitutively produced most of the intestinal IL-22 and that the symbiotic microbiota repressed this function through epithelial expression of IL-25. This function was greater in the absence of adaptive immunity and was fully restored and required after epithelial damage, which demonstrates a central role for RORγt+ ILCs in intestinal homeostasis. Our data identify a finely tuned equilibrium among intestinal symbionts, adaptive immunity and RORγt+ ILCs. 相似文献
54.
Dumoutier L de Heusch M Orabona C Satoh-Takayama N Eberl G Sirard JC Di Santo JP Renauld JC 《European journal of immunology》2011,41(4):1075-1085
IL-22 is a Th17 cytokine that plays a key role in immune responses against extracellular bacteria. In mucosal lymphoid tissues, IL-22 production is mainly due to an IL-23-responsive NK-like cell subset that shares some markers with lymphoid tissue inducer (LTi) cells. Here, we identified a new spleen cell population responsible for IL-22 production upon either in vitro stimulation by anti-CD3 antibodies or in vivo stimulation by lipopolysaccharide (LPS) via IL-2- and an IL-23-dependent mechanisms, respectively. These cells represent 1% of spleen cells from recombination activating gene (Rag2)-deficient mice, and correspond to a discrete innate lymphoid cell population expressing CD25, CCR6 and IL-7R. This population comprises 60-70% CD4(+) cells, which produce IL-22, and are still present in common γ chain-deficient mice; the CD4(-) subset coexpresses IL-22 and IL-17, and is common γ chain-dependent. The importance of IL-22 production for the LPS-triggered response is highlighted by the fact that IL-22-deficient mice are more resistant to LPS-induced mortality. 相似文献
55.
Salcedo M Colucci F Dyson PJ Cotterill LA Lemonnier FA Kourilsky P Di Santo JP Ljunggren HG Abastado JP 《European journal of immunology》2000,30(4):1094-1101
NK cells acquire the ability to recognize MHC class I molecules during development. Studies with Qa-1(b) tetramers (Qa-1 tetramers) showed that nearly all NK1.1(+) cells from newborn C57BL/6 mice express Qa-1-binding receptors. Cytotoxic activity of these cells is fully inhibited by Qa-1 ligands on target cells. In contrast, neither receptors for H-2K(b) nor H-2D(b) were observed on NK1.1(+) cells from newborn mice. After birth, frequencies of Qa-1 tetramer(+)/ NK1.1(+) cells gradually decrease as the number of Ly49(+) /NK1.1(+) cells increases. Cell transfer studies showed that Qa-1 tetramer(+) cells from newborn mice do not lose expression of Qa-1 receptors, but that they further acquire expression of Ly49 molecules. Acquisition of Qa-1-binding receptors appears largely independent of host MHC class I molecules, as observed in studies using beta2-microglobulin-deficient (beta2m(-/-)) mice as well as K(b)/ D(b-/-) and K(b)/D(b)/beta2m(-/-) mice. The present results suggest that Qa-1-binding receptors play an important role in the specificity of developing NK cells, and suggest that these cells rely mainly on inhibitory receptors specific for non-classical MHC class I molecules to maintain self tolerance during the first weeks of life. 相似文献
56.
Lymphoid homeostasis is required to ensure immune responsiveness and to prevent immunodeficiency. As such, the immune system must maintain distinct populations of na?ve T cells that are able to respond to new antigens as well as memory T cells specific to those antigens it has already encountered. Though both na?ve and memory T cells reside in and traffic through secondary lymphoid organs, there is growing evidence that the two populations may be regulated differently. We show here that na?ve T cell survival and memory T cell survival have different requirements for cytokines (including the interleukins IL-2, IL-4, IL-7, IL-9 and IL-15) that use the common cytokine receptor gamma chain (gamma c). Using monoclonal populations of antigen-specific CD4+ T cells, we found that na?ve T cells cannot survive without gamma c, whereas memory T cells show no such requirement. In contrast, neither na?ve nor gamma c-deficient memory T cells were impaired in their ability to proliferate and produce cytokines in response to in vivo antigenic stimulation. These data call into question the physiological role of gamma c-dependent cytokines as T cell growth factors and show that na?ve and memory CD4+ T cell survival is maintained by distinct mechanisms. 相似文献
57.
58.
Francesco Paolo Mangino Federico Romano Giovanni Di Lorenzo Francesca Buonomo Davide De Santo Federica Scrimin Giuseppe Ricci 《Journal of minimally invasive gynecology》2019,26(6):1011-1012
Study ObjectiveTo evaluate the efficacy of total surgical treatment of ectopic cervical pregnancy [1] with a minimally invasive approach performed by hysteroscopy [2].DesignStep-by-step video demonstration of the surgical technique using 5 mm hysteroscopy followed by 10 mm resectoscopy.SettingA research and university hospital (IRCCS Burlo Garofolo, Trieste, Italy).PatientsA 41-year-old woman with an ultrasound diagnosis of ectopic cervical pregnancy at 6 + 6 weeks of gestation with a beta human chorionic gonadotropin serum level of 55.951 mUI/mL.InterventionsWe performed a 2-step technique using 5- and 10-mm hysteroscopy (Video 1). During the first step, a 5-mm Bettocchi hysteroscope (Karl Storz, Tuttlingen, Germany) with a 5F bipolar electrode Versapoint Twizzle (Gynecare, Menlo Park, CA) was used. In this phase, the gestational sac was identified in order to confirm the diagnosis and its site of implantation. Later, the gestational sac was opened, and the pregnancy was terminated by cord section under an embryoscopic view (Fig. 1). Finally, a partial vessel coagulation was performed. Afterward, the cervix was dilated, and a resectoscopy was performed. During the second step, a 10-mm Gynecare resectoscope with the bipolar Gynecare Versapoint was used and the gestational sac with the embryo was removed; subsequently, a complete chorial villi resection was achieved. At last, a coagulation of bleeding vessels on the implantation site in order to control the hemostasis was performed (Fig. 2).Measurements and Main ResultsThe study was approved by the institutional review board. The patient was discharged 24 hours after the procedure with an uneventful postoperative course, and the beta human chorionic gonadotropin serum level became negative in 20 days. After 40 days, the ultrasound cervical findings were regular, whereas office hysteroscopy showed the implantation site scar. After 5 months, the patient was pregnant with regular intrauterine implantation (Fig. 3).ConclusionThe total hysteroscopic approach with a 2-step technique offers an effective, safe, and minimally invasive surgical treatment to ectopic cervical pregnancy. Considering that our method, in contrast with the recent literature 3, 4, 5, is performed without any medical treatment, we reported for the first time an approach, that deserve more clinical data to confirm its effectiveness. 相似文献
59.
Cloning and characterization of two catechol 1,2-dioxygenase genes from Acinetobacter radioresistens S13 总被引:2,自引:0,他引:2
Caposio P Pessione E Giuffrida G Conti A Landolfo S Giunta C Gribaudo G 《Research in microbiology》2002,153(2):69-74
Two novel catechol 1,2-dioxygenase (C 1,2-O) genes have been isolated from an Acinetobacter radioresistens strain that grows on phenol or benzoate as sole carbon and energy source. Designated as catA(A) and catA(B), they encode proteins composed of 314 and 306 amino acids, whose deduced sequences indicate that they have approximately 53% identity, whereas their NH2-terminal and COOH-terminal regions have no sequences in common. This may explain their different thermal and pH stability. Polyclonal antibodies raised against an amino-terminal CatA(A) peptide or the whole CatA(B) protein were used to establish their inducible and differential expression patterns upon bacterial growth in phenol or benzoate. The CatA(A) protein (IsoA) was induced by both phenol and benzoate though with different kinetics, whereas the catA(B) product (IsoB) was constitutively produced at low levels that increased only during growth in the presence of benzoate. 相似文献
60.
Conditional ablation of NKp46+ cells using a novel Ncr1greenCre mouse strain: NK cells are essential for protection against pulmonary B16 metastases 下载免费PDF全文
Leila Ben Merzoug Solenne Marie Naoko Satoh‐Takayama Sarah Lesjean Marcello Albanesi Hervé Luche Hans Jörg Fehling James P. Di Santo Christian A. J. Vosshenrich 《European journal of immunology》2014,44(11):3380-3391
To study gene functions specifically in NKp46+ cells we developed novel Cre mice allowing for conditional gene targeting in cells expressing Ncr1 (encoding NKp46). We generated transgenic Ncr1greenCre mice carrying an EGFPcre fusion under the control of a proximal Ncr1 promoter that faithfully directed EGFPcre expression to NKp46+ cells from lymphoid and nonlymphoid tissues. This approach allowed for direct detection of Cre‐expressing NKp46+ cells via their GFP signature by flow cytometry and histology. Cre was functional as evidenced by the NKp46+ cell‐specific expression of RFP in Ncr1greenCreRosa‐dtRFP reporter mice. We generated Ncr1greenCreIl2rgfl/fl mice that lack NKp46+ cells in an otherwise intact hematopoietic environment. Il2rg encodes the common gamma chain (γc), which is an essential receptor subunit for cytokines (IL‐2, ‐4, ‐7, ‐9, ‐15, and ‐21) that stimulate lymphocyte development and function. In Ncr1greenCreIl2rgfl/fl mice, NK cells are severely reduced and the few remaining NKp46+ cells escaping γc deletion failed to express GFP. Using this new NK‐cell‐deficient model, we demonstrate that the homeostasis of NKp46+ cells from all tissues (including the recently described intraepithelial ILC1 subset) requires Il2rg. Finally, Ncr1greenCreIl2rgfl/fl mice are unable to reject B16 lung metastases demonstrating the essential role of NKp46+ cells in antimelanoma immune responses. 相似文献