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31.
32.
Rausa Marialuisa Spada Gea Elena Patron Elisabetta Pierangeli Giulia Palomba Daniela 《Neurological sciences》2022,43(5):3283-3295
Neurological Sciences - Maladaptive cognitive strategies and reduced autonomic flexibility have been reported in chronic pain conditions. No study to date addressed the effects of maladaptive... 相似文献
33.
Screening of PRKAR1A and PDE4D in a Large Italian Series of Patients Clinically Diagnosed With Albright Hereditary Osteodystrophy and/or Pseudohypoparathyroidism 下载免费PDF全文
Luisa de Sanctis Federica Giachero Elisa Verrua Maria Segni Laura Mazzanti Valentina Boldrin Alma Toromanovic Anna Spada Giovanna Mantovani 《Journal of bone and mineral research》2016,31(6):1215-1224
The cyclic adenosine monophosphate (cAMP) intracellular signaling pathway mediates the physiological effects of several hormones and neurotransmitters, acting by the activation of G‐protein coupled receptors (GPCRs) and several downstream intracellular effectors, including the heterotrimeric stimulatory G‐protein (Gs), the cAMP‐dependent protein kinase A (PKA), and cAMP‐specific phosphodiesterases (PDEs). Defective G‐protein–mediated signaling has been associated with an increasing number of disorders, including Albright hereditary osteodistrophy (AHO) and pseudohypoparathyroidism (PHP), a heterogeneous group of rare genetic metabolic disorders resulting from molecular defects at the GNAS locus. Moreover, mutations in PRKAR1A and PDE4D genes have been recently detected in patients with acrodysostosis (ACRDYS), showing a skeletal and endocrinological phenotype partially overlapping with AHO/PHP. Despite the high detection rate of molecular defects by currently available molecular approaches, about 30% of AHO/PHP patients still lack a molecular diagnosis, hence the need to screen patients negative for GNAS epi/genetic defects also for chromosomal regions and genes associated with diseases that undergo differential diagnosis with PHP. According to the growing knowledge on Gsα‐cAMP signaling‐linked disorders, we investigated our series of patients (n = 81) with a clinical diagnosis of PHP/AHO but negative for GNAS anomalies for the presence of novel genetic variants at PRKAR1A and PDE4D genes. Our work allowed the detection of 8 novel missense variants affecting genes so far associated with ACRDYS in 9 patients. Our data further confirm the molecular and clinical overlap among these disorders. We present the data collected from a large series of patients and a brief review of the literature in order to compare our findings with already published data; to look for PRKAR1A/PDE4D mutation spectrum, recurrent mutations, and mutation hot spots; and to identify specific clinical features associated with ACRDYS that deserve surveillance during follow‐up. © 2016 American Society for Bone and Mineral Research. 相似文献
34.
Enea Spada Giovanni Rezza Anna Rosa Garbuglia Flavia Lucia Lombardo Ornella Zuccaro Francesca Menniti Ippolito Elisabetta Cupellaro Stefania Capone Maria Rosaria Capobianchi Alfredo Nicosia Riccardo Cortese Antonella Folgori Alfonso Mele The Collaborative Study Group 《Journal of urban health》2018,95(1):99-110
So far, only three small outdated studies have investigated hepatitis C virus (HCV) incidence and risk factors among illicit drug users (DUs) in Italy. Thus, during 2007–2010, we conducted a prospective cohort study among DUs attending 17 Italian rehabilitation centers serving urban areas. Two hundred eighty-four HCV-uninfected DUs were prospectively followed by interview and anti-HCV antibody and RNA testing every 6 months. Incidence was calculated using the person-years method. Infection predictors were assessed by time-dependent Cox analysis. Participants were mostly male (83.4%), under opioid substitution therapy (OST) (78.9%), non-injecting DUs (67.9%), and with a mean age of 30.8. Ninety-one of 224 DUs initially under OST interrupted treatment during the follow-up. Overall HCV incidence was 5.83/100 person-years at risk (PYAR) [95% confidence intervals (CI), 3.63–9.38]. The incidence did not significantly differ according the participants’ sociodemographic characteristics or the degree of urbanization of the towns involved in the study. The incidence was higher for DUs under than for those not under OST (6.23 vs 4.50/100 PYAR; p = 0.681). Incidence was also higher for those with than for those without OST interruption (7.17 vs 5.04/100 PYAR; p = 0.55). However, all these differences were non-significant. At last follow-up visit, a significant decrease in frequency of sharing equipment for preparation/using drugs (by injection or not) was observed by analyzing either the whole cohort or DUs under OST only. Anti-HCV seroconversion resulted independently associated with sharing drug preparation/use equipment, backloading, having a HCV-positive sexual partner, or household and (marginally) intravenous injection. In this study, HCV incidence was non-negligible and OST seemed to lack effectiveness in reducing it. In Italy, implementation of combined harm reduction interventions and antiviral treatment of chronically infected DUs would be needed. 相似文献
35.
Joo Augusto Franco Leonel Geovanna Vioti Maria Luana Alves Julia Cristina Benassi Diogo Tiago da Silva Julio Cesar Pereira Spada Vera Letticie de Azevedo Ruiz Wilma Aparecida Starke-Buzetti Rodrigo Martins Soares Trícia Maria Ferreira de Sousa Oliveira 《Transboundary and Emerging Diseases》2020,67(5):2013-2019
An epidemiological Leishmania spp. and entomological Phlebotomine sandflies survey was performed in cat shelters at leishmaniasis endemic area of Brazil. Blood and conjunctival swab (CS) samples were collected from 94 cats in two animal protection shelters. These samples were subjected to serological tests using the indirect immunofluorescence antibody test (IFAT) and indirect enzyme‐linked immunosorbent assay (ELISA) and to molecular test by polymerase chain reaction (PCR). In addition, a Phlebotomine sandflies survey was performed in the same shelters. The analyses revealed a positivity of 31.91% (30/94) through ELISA and 29.79% (28/94) through IFAT. The two serological tests showed a positive association with perfect agreement (k = 0.925). None of the cats were positive by Leishmania spp. DNA. One Lutzomyia (Lutzomyia) longipalpis male was found in one of the cat shelters. The results and the implications of our findings are discussed below. 相似文献
36.
Kevin M. Rose Stephanie J. Spada Rebecca Broeckel Kristin L. McNally Vanessa M. Hirsch Sonja M. Best Fadila Bouamr 《Viruses》2021,13(3)
An evolutionary arms race has been ongoing between retroviruses and their primate hosts for millions of years. Within the last century, a zoonotic transmission introduced the Human Immunodeficiency Virus (HIV-1), a retrovirus, to the human population that has claimed the lives of millions of individuals and is still infecting over a million people every year. To counteract retroviruses such as this, primates including humans have evolved an innate immune sensor for the retroviral capsid lattice known as TRIM5α. Although the molecular basis for its ability to restrict retroviruses is debated, it is currently accepted that TRIM5α forms higher-order assemblies around the incoming retroviral capsid that are not only disruptive for the virus lifecycle, but also trigger the activation of an antiviral state. More recently, it was discovered that TRIM5α restriction is broader than previously thought because it restricts not only the human retroelement LINE-1, but also the tick-borne flaviviruses, an emergent group of RNA viruses that have vastly different strategies for replication compared to retroviruses. This review focuses on the underlying mechanisms of TRIM5α-mediated restriction of retroelements and flaviviruses and how they differ from the more widely known ability of TRIM5α to restrict retroviruses. 相似文献
37.
Grigg AP; Roberts AW; Raunow H; Houghton S; Layton JE; Boyd AW; McGrath KM; Maher D 《Blood》1995,86(12):4437-4445
To define an optimal regimen for mobilizing and collecting peripheral blood progenitor cells (PBPC) for use in allogeneic transplantation, we evaluated the kinetics of mobilization by filgrastim (recombinant met- human granulocyte colony-stimulating factor [r-metHuG-CSF]) in normal volunteers. Filgrastim was injected subcutaneously for up to 10 days at a dose of 3 (n = 10), 5 (n = 5), or 10 micrograms/kg/d (n = 15). A subset of volunteers from each dose cohort underwent a 7L leukapheresis on study day 6 (after 5 days of filgrastim). Granulocyte-macrophage colony-forming cell (GM-CFC) numbers in the blood were maximal after 5 days of filgrastim; a broader peak was evident for CD34+ cells between days 4 and 6. The 95% confidence intervals (CI) for mean number of PBPC per milliliter of blood in the three dose cohorts overlapped on each study day. However, on the peak day, CD34+ cells were significantly higher in the 10 micrograms/kg/d cohort than in a pool of the 3 and 5 micrograms/kg/d cohorts. Mobilization was not significantly influenced by volunteer age or sex. Leukapheresis products obtained at the 10 micrograms/kg/d dose level contained a median GM-CFC number of 93 x 10(4)/kg (range, 50 x 10(4)/kg to 172 x 10(4)/kg). Collections from volunteers receiving lower doses of filgrastim contained a median GM- CFC number of 36 x 10(4)/kg (range, 5 x 10(4)/kg to 204 x 10(4)/kg). The measurement of CD34+ cells per milliliter of blood on the day of leukapheresis predicted the total yield of PBPC in the leukapheresis product (r = .87, P < .0001). Assuming a minimum GM-CFC requirement of 50 x 10(4)/kg (based on our experience with autologous PBPC transplantation), all seven leukapheresis products obtained at the 10 micrograms/kg/d dose level were potentially sufficient for allogeneic transplantation purposes. We conclude that in normal donors, filgrastim 10 micrograms/kg/d for 5 days with a single leukapheresis on the following day is a highly effective regimen for PBPC mobilization and collection. Further studies are required to determine whether PBPC collected with this regimen reliably produce rapid and sustained engraftment in allogeneic recipients. 相似文献
38.
The activation of factor XI initiates the intrinsic coagulation pathway. Until recently it was believed that the main activator of factor XI is factor XIIa in conjunction with the cofactor high molecular weight kininogen on a negatively charged surface. Two recent reports have presented evidence that in a purified system factor XI is activatable by thrombin together with the soluble polyanion dextran sulfate. To assess the physiological relevance of these findings we studied the activation of factor XI in normal and factor XII-deficient plasma. We used either kaolin/cephalin or dextran sulfate as a surface for the intrinsic coagulation pathway, tissue factor to generate thrombin via the extrinsic pathway, or the addition of alpha-thrombin directly. 125I-factor XI, added to factor XI-deficient plasma at physiologic concentrations (35 nmol/L), is rapidly cleaved on incubation with kaolin. The kinetics appear to be exponential with half the maximum cleavage at 5 minutes. Similar kinetics of factor XI cleavage are seen when 40 nmol/L factor XIIa (equal to 10% of factor XII activation) is added to factor XII-deficient plasma if an activating surface is provided. Tissue factor (1:500) added to plasma did not induce cleavage of factor XI during a 90-minute incubation, although fibrin formation within 30 seconds indicated that thrombin was generated via the extrinsic pathway. Adding 1 mumol/L alpha-thrombin (equivalent to 50% prothrombin activation) directly to factor XII deficient or normal plasma (with or without kaolin/cephalin/Ca2+ or dextran sulfate) led to instantaneous fibrinogen cleavage, but again no cleavage of factor XI was observable. We conclude that in plasma surroundings factor XI is not activated by thrombin, and that proposals of thrombin initiation of the intrinsic coagulation cascade are not supportable. 相似文献
39.
The regulation of myelopoiesis was evaluated in B6D2F1 mice inoculated with Friend virus complex (spleen focus-forming virus plus helper virus) or helper virus alone by analyzing acidic isoferritin (AIF) and lactoferrin (LF) interactions with target cells. Under normal conditions, AIF suppresses colony and cluster formation by an Ia- antigen-positive cycling subpopulation of mouse granulocyte-macrophage progenitor cells (CFU-GM). Under the same conditions, the release of AIF-inhibitory activity and granulocyte-macrophage colony stimulatory factors (GM-CSF) from an Ia-antigen-positive subpopulation of monocytes and macrophages is suppressed by LF. Within one to two days after inoculation in vivo with Friend virus complex or helper virus, mouse CFU-GM become insensitive in vitro to suppression by purified human AIF as well as crude mouse AIF, and by four days, bone marrow, spleen, and thymus cells of these mice release much greater quantities of AIF- inhibitory activity than the cells from mice injected with control medium. The Friend virus complex itself has no influence in vitro on CFU-GM from normal mice. In addition, the release of AIF-inhibitory activity from bone marrow, spleen, and resident peritoneal cells and the release of GM-CSF from resident peritoneal cells of mice infected with Friend virus complex are not suppressed by LF. The inability of AIF to suppress colony formation by bone marrow and spleen CFU-GM from mice infected with Friend virus complex is associated with the loss of Ia (I-A subregion) antigens from CFU-GM, even though CFU-GM are in cycle. The nonresponsiveness of bone marrow, spleen, and peritoneal cells from these mice to LF suppression of AIF release and the inability of LF to influence GM-CSF release from peritoneal cells is associated with loss of Ia antigens from these cells. The above abnormalities are similar to the defects noted using cells from patients with leukemia. These results suggest that mice infected with Friend virus complex can serve as a model for investigating abnormalities in cell regulation and their relationships to disease progression. 相似文献
40.
O'Malley CJ; Rasko JE; Basser RL; McGrath KM; Cebon J; Grigg AP; Hopkins W; Cohen B; O'Byrne J; Green MD; Fox RM; Berndt MC; Begley CG 《Blood》1996,88(9):3288-3298
This report describes the effect of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) on platelet production and platelet function in humans. Subjects with advanced solid tumors received PEG-rHuMGDF daily for up to 10 days. There was no increase in circulating platelet count at doses of 0.03 or 0.1 microgram/kg/d by day 12 of study. At doses of 0.3 and 1.0 microgram/kg/d there was a threefold median increase (maximum 10-fold) in platelet count by day 16. The platelets produced in vivo in response to PEG-rHuMGDF showed unchanged aggregation and adenosine triphosphate (ATP)-release responses in in vitro assays. Tests included aggregation and release of ATP in response to adenosine diphosphate (ADP) (10, 5, 2.5, and 1.25 mumol/L), collagen (2 micrograms/mL), thrombin-receptor agonist peptide (TRAP, 10 mumol/L) and ristocetin (1.5 mg/mL). Administration of aspirin to an individual with platelet count of 1,771 x 10(3)/L resulted in the typical aspirin-induced ablation of the normal aggregation and ATP-release response to stimulation with arachidonic acid (0.5 mg/mL), collagen, and ADP (2.5 and 1.25 mumol/L). There was no change in the expression of the platelet-surface activation marker CD62P (P-selectin) nor induction of the fibrinogen binding site on glycoprotein IIb/IIIa as reported by the monoclonal antibody, D3GP3. An elevation of reticulated platelets was evident after 3 days of treatment with PEG-rHuMGDF and preceded the increase in circulating platelet count by 5 to 8 days; this reflected the production of new platelets in response to PEG-rHuMGDF. At later time points, the mean platelet volume (MPV) decreased in a manner inversely proportional to the platelet count. Levels of plasma glycocalicin, a measure of platelet turnover, rose 3 days after the initial increase in the peripheral platelet count. The level of plasma glycocalicin was proportional to the total platelet mass, suggesting that platelets generated in response to PEG-rHuMGDF were not more actively destroyed. Thus, the administration of PEG-rHuMGDF, to humans, increased the circulating platelet count and resulted in fully functional platelets, which showed no detectable increase in reactivity nor alteration in activation status. 相似文献