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61.
62.
Influenza A virus (IAV) is a relevant respiratory tract pathogen leading to a great number of deaths and hospitalizations worldwide. Secondary bacterial infections are a very common cause of IAV associated morbidity and mortality. The robust inflammatory response that follows infection is important for the control of virus proliferation but is also associated with lung damage, morbidity and death. The role of the different components of immune response underlying protection or disease during IAV infection is not completely elucidated. Overall, in the context of IAV infection, inflammation is a ‘double edge sword’ necessary to control infection but causing disease. Therefore, a growing number of studies suggest that immunomodulatory strategies may improve disease outcome without affecting the ability of the host to deal with infection. This review summarizes recent aspects of the inflammatory responses triggered by IAV that are preferentially involved in causing severe pulmonary disease and the anti-inflammatory strategies that have been suggested to treat influenza induced immunopathology. 相似文献
63.
Francesca Parisi Cristiana Berti Chiara Mandò Anna Martinelli Cristina Mazzali 《The journal of maternal-fetal & neonatal medicine》2017,30(15):1787-1792
Purpose: Iron supplementation is associated with side effects and overload risk. We compared different regimens of iron supplementation on maternal hematological status and pregnancy outcome in a cohort of healthy pregnant women.Materials and methods: Eighty non-anemic women with a normal singleton pregnancy were recruited at 11–13 weeks and randomized into controls (C; n?=?20) and groups supplemented with ferrous iron 30?mg (FI; n?=?20), liposomal iron 14?mg (Sideral® Pharmanutra, Pisa PI, Italy) (LI14; n?=?20) and liposomal iron 28?mg/daily (LI28; n?=?20) up to 6 weeks post-partum. Longitudinal maternal blood samples for iron markers were collected. Data on birth outcome were recorded. The treatment effect was evaluated using a mixed-effect regression model.Results: Both LI28 and LI14 groups showed significantly higher hemoglobin and ferritin concentrations compared with controls. Birth weight showed a trend to increase with supplementation, resulting in higher birth weight in the LI28 group compared with controls (3499?±?464.1?g and 3092?±?469.5?g, respectively, p?0.01).Conclusions: Our data show the effectiveness of 28?mg and 14?mg LI on maternal anemia prevention, as previously reported with FI 40?mg. LI has similar effects of higher doses of ferrous iron on maternal hematological parameters, thus allowing to reduce iron doses and side effects. 相似文献
64.
Azevedo MS Yuan L Iosef C Chang KO Kim Y Nguyen TV Saif LJ 《Clinical and diagnostic laboratory immunology》2004,11(1):12-20
A sequential mucosal prime-boost vaccine regimen of oral attenuated (Att) human rotavirus (HRV) priming followed by intranasal (i.n.) boosting with rotavirus protein VP2 and VP6 rotavirus-like particles (2/6-VLPs) has previously been shown to be effective for induction of intestinal antibody-secreting cell (ASC) responses and protection in gnotobiotic pigs. Because serum or fecal antibody titers, but not intestinal ASC responses, can be used as potential markers of protective immunity in clinical vaccine trials, we determined the serum and intestinal antibody responses to this prime-boost rotavirus vaccine regimen and the correlations with protection. Gnotobiotic pigs were vaccinated with one of the two sequential vaccines: AttHRV orally preceding 2/6-VLP (VLP2x) vaccination (AttHRV/VLP2x) or following VLP2x vaccination (VLP2x/AttHRV) given i.n. with a mutant Escherichia coli heat-labile toxin (mLT) as adjuvant. These vaccines were also compared with three i.n. doses of VLP+mLT (VLP3x) and one and three oral doses of AttHRV (AttHRV1x and AttHRV3x, respectively). Before challenge all pigs in the AttHRV/VLP2x group seroconverted to positivity for serum immunoglobulin A (IgA) antibodies. The pigs in this group also had significantly higher (P < 0.05) intestinal IgA antibody titers pre- and postchallenge and IgG antibody titers postchallenge compared to those in the other groups. Statistical analyses of the correlations between serum IgM, IgA, IgG, and virus-neutralizing antibody titers and protection demonstrated that each of these was an indicator of protective immunity induced by the AttHRV3x and the AttHRV/VLP2x regimens. However, only IgA and not IgM or IgG antibody titers in serum were highly correlated (R2 = 0.89; P < 0.001) with the corresponding isotype antibody (IgA) titers in the intestines among all the vaccinated groups, indicating that the IgA antibody titer is probably the most reliable indicator of protection. 相似文献
65.
Faravelli C Abrardi L Bartolozzi D Cecchi C Cosci F D'Adamo D Lo Iacono B Ravaldi C Scarpato MA Truglia E Rossi Prodi PM Rosi S 《Psychotherapy and psychosomatics》2004,73(4):226-234
BACKGROUND: It has been argued that lay interviewers' use of fully-structured interviews could lead to a diagnostic pattern different to that by treating physicians. Clinical interviewers in community samples should probably identify cases that are closer to those seen in clinical settings. The greatest advantage of using clinical interviewers consists of the immediate assessment of a possible psychopathology, i.e. the evaluation of current disorders. METHODS: Two thousand three hundred and sixty-three citizens from the community of Sesto Fiorentino, Italy, were interviewed by their own general practitioners using the Mini International Neuropsychiatric Interview (MINI). Positive cases for any lifetime psychiatric disorder as well as a random sample of the negative cases were re-interviewed by psychiatrists or trained residents in psychiatry using the Florence Psychiatric Interview (FPI). RESULTS: The point prevalence for any current disorder was 8.7%; the two disorders with the highest prevalence were generalised anxiety disorder (2.9%) and major depressive episode (2.7%). The figures increase about 50% when the sub-threshold sequelae of previous disorders are considered. Current comorbidity was generally high. The one-year prevalence of any disorder was 10.6%. Ninety-two percent of the cases sought help, 82% were being treated at the moment of interview. Social impairment was considerable. CONCLUSIONS: The period prevalence rates for most of the disorders considered were generally comparable with the range defined by previous studies conducted in other Western countries, despite using different methodologies. Conversely, the use of health facilities, the treatment received and the social impairment were much higher than those reported by the other studies, suggesting a greater similarity with the clinical samples. 相似文献
66.
Bellan C De Falco G Lazzi S Micheli P Vicidomini S Schürfeld K Amato T Palumbo A Bagella L Sabattini E Bartolommei S Hummel M Pileri S Tosi P Leoncini L Giordano A 《The Journal of pathology》2004,203(4):946-952
CDK9 is a member of the CDC2-like family of kinases. Its cyclin partners are members of the CYCLIN T family (T1, T2a, and T2b) and CYCLIN K. The CDK9/CYCLIN T1 complex is very important in the differentiation programme of several cell types, controlling specific differentiation pathways. Limited data are available regarding the expression of CDK9/CYCLIN T1 in haematopoietic and lymphoid tissues. The aim of this study was to analyse the expression of the CDK9/CYCLIN T1 complex in lymphoid tissue, in order to assess its role in B- and T-cell differentiation and lymphomagenesis. CDK9/CYCLIN T1 expression was found by immunohistochemistry in precursor B and T cells. In peripheral lymphoid tissues, germinal centre cells and scattered B- and T-cell blasts in interfollicular areas expressed CDK9/CYCLIN T1, while mantle cells, plasma cells, and small resting T-lymphocytes displayed no expression of either molecule. CDK9/CYCLIN T1 expression therefore appears to be related to particular stages of lymphoid differentiation/activation. CDK9 and CYCLIN T1 were highly expressed in lymphomas derived from precursor B and T cells, from germinal centre cells, such as follicular lymphomas, and from activated T cells (ie anaplastic large cell lymphomas). Hodgkin and Reed-Sternberg cells of classical Hodgkin's lymphoma also showed strong nuclear staining. Diffuse large B-cell, Burkitt's lymphomas, and peripheral T-cell lymphomas, among T-cell lymphoproliferative disorders, showed a wide range of values. No expression of CDK9 or CYCLIN T1 was detected in mantle cell and marginal zone lymphomas. However, at the mRNA level, an imbalance in the CDK9/CYCLIN T1 ratio was found in follicular lymphoma and diffuse large B-cell lymphomas with germinal centre phenotype, and in the cell lines of classical Hodgkin's lymphomas, Burkitt's lymphomas, and anaplastic large cell lymphoma, in comparison with reactive lymph nodes. These results suggest that the CDK9/CYCLIN T1 complex may affect the activation and differentiation programme of lymphoid cells. The molecular mechanism through which the CDK9/CYCLIN T1 complex is altered in malignant transformation needs to be elucidated. 相似文献
67.
Tanase CE Popa MI Verestiuc L 《Journal of biomedical materials research. Part B, Applied biomaterials》2012,100(3):700-708
A novel biomimetic technique for obtaining chitosan-calcium phosphates (Cs-CP) scaffolds are presented: calcium phosphates are precipitated from its precursors, CaCl(2) and NaH(2) PO(4) on the Cs matrix, under physiological conditions (human body temperature and body fluid pH; 37°C and pH = 7.2, respectively). Materials composition and structure have been confirmed by various techniques: elemental analysis, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), and scanning electron microscopy (SEM). FTIR and SEM data have shown the arrangement of the calcium phosphates-hydroxyapatite (CP-Hap) onto Cs matrix. In this case the polymer is acting as glue, bonding the calcium phosphates crystals. Behavior in biological simulated fluids (phosphate buffer solution-PBS and PBS-albumin) revealed an important contribution of the chelation between -NH3(+) and Ca(2+) on the scaffold interaction with aqueous mediums; increased quantities of chitosan in composites permit the interaction with human albumin and improve the retention of fluid. The composites are slightly degraded by the lysozyme which facilitates an in vivo degradation control of bone substitutes. Modulus of elasticity is strongly dependent of the ratio chitosan/calcium phosphates and recommends the obtained biomimetic composites as promising materials for a prospective bone application. 相似文献
68.
Sacchi A Cappelli G Cairo C Martino A Sanarico N D'Offizi G Pupillo LP Chenal H De Libero G Colizzi V Vendetti S 《Journal of acquired immune deficiency syndromes (1999)》2007,46(5):519-528
Monocyte differentiation into dendritic cells (DCs) depends on microenvironmental conditions. In this study, the capacity of human monocytes to differentiate into mature DCs and their ability to induce an antiviral immune response was investigated in HIV-infected patients. In healthy subjects, monocytes differentiate into CD1a+ DCs in the presence of granulocyte macrophage colony-stimulating factor and interleukin (IL)-4 and matured in the presence of lipopolysaccharide. Here, we found that in 30% and 45% of HIV-infected white and African subjects, respectively, monocytes gave rise to a homogeneous CD1a* DC population. In the patients who gave rise only to the CD1a* DCs, this population spontaneously produced IL-10 but not IL-12, and induced a T helper 2-like immune response when cultured with human T cells isolated from cord blood mononuclear cells. In patients with monocytes differentiated into CD1a* DCs, a high percentage of HIV-specific CD4 T cells producing IL-4 were seen in the peripheral blood. Furthermore, differentiation of monocytes into DCs with CD1a* phenotype correlated with low CD4 T-cell counts and high viral loads in HIV-infected subjects. These results suggest that the differentiation of monocytes into CD1a* DCs may be a phenotypic marker associated with progression of the disease. 相似文献
69.
Outcome of children hospitalized with community-acquired pneumonia treated with aqueous penicillin G
OBJECTIVE:
To describe the evolution and outcome of children hospitalized with community‐acquired pneumonia receiving penicillin .METHODS:
A search was carried out for all hospitalized community‐acquired pneumonia cases in a 37‐month period. Inclusion criteria comprised age ≥2 months, intravenous penicillin G use at 200,000 IU/kg/day for ≥48 h and chest x‐ray results. Confounders leading to exclusion included underlying debilitating or chronic pulmonary illnesses, nosocomial pneumonia or transference to another hospital. Pneumonia was confirmed if a pulmonary infiltrate or pleural effusion was described by an independent radiologist blind to the clinical information. Data on admission and evolution were entered on a standardized form.RESULTS:
Of 154 studied cases, 123 (80%) and 40 (26%) had pulmonary infiltrate or pleural effusion, respectively. Penicilli was substituted by other antibiotics in 28 (18%) patients, in whom the sole significant decrease was in the frequency of tachypnea from the first to the second day of treatment (86% vs. 50%, p = 0.008). Among patients treated exclusively with penicillin G, fever (46% vs. 26%, p = 0.002), tachypnea (74% vs. 59%, p = 0.003), chest indrawing (29% vs. 13%, p<0.001) and nasal flaring (10% vs. 1.6%, p = 0.001) frequencies significantly decreased from admission to the first day of treatment. Patients treated with other antimicrobial agents stayed longer in the hospital than those treated solely with penicillin G (16±6 vs. 8±4 days, p<0.001, mean difference (95% confidence interval) 8 (6–10)). None of the studied patients died.CONCLUSION:
Penicillin G successfully treated 82% (126/154) of the study group and improvement was marked on the first day of treatment. 相似文献70.