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1.
Phys Rev Lett ; 129(3): 030603, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35905355

RESUMO

Modeling noisy oscillations of active systems is one of the current challenges in physics and biology. Because the physical mechanisms of such processes are often difficult to identify, we propose a linear stochastic model driven by a non-Markovian bistable noise that is capable of generating self-sustained periodic oscillation. We derive analytical predictions for most relevant dynamical and thermodynamic properties of the model. This minimal model turns out to describe accurately bistablelike oscillatory motion of hair bundles in bullfrog sacculus, extracted from experimental data. Based on and in agreement with these data, we estimate the power required to sustain such active oscillations to be of the order of 100 k_{B}T per oscillation cycle.


Assuntos
Células Ciliadas Auditivas , Física , Animais , Modelos Lineares , Rana catesbeiana
2.
Dialect Anthropol ; 46(2): 163-182, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35729915

RESUMO

This article addresses the Seasonal Agricultural Worker Program (SAWP) between Mexico and Canada by examining the forms of disposability and job insecurity of Mexicans employed in Canadian agribusiness. We argue that the Seasonal Agricultural Worker Program has exacerbated the precarity and disposability of Mexican workers by restructuring family dynamics and care chains. This article represents a critique of the SAWP as a model of regulated labor migration, serving as a basis for analyzing the consequences of the proletarianization of the Mexican peasantry and its use as disposable labor for export.

3.
J Endocrinol Invest ; 44(9): 1971-1979, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33515211

RESUMO

PURPOSE: Hypogonadism is frequent in HIV-infected men and might impact on metabolic and sexual health. Low testosterone results from either primary testicular damage, secondary hypothalamic-pituitary dysfunction, or from liver-derived sex-hormone-binding-globulin (SHBG) elevation, with consequent reduction of free testosterone. The relationship between liver fibrosis and hypogonadism in HIV-infected men is unknown. Aim of our study was to determine the prevalence and type of hypogonadism in a cohort of HIV-infected men and its relationship with liver fibrosis. METHODS: We performed a cross-sectional retrospective study including 107 HIV-infected men (median age 54 years) with hypogonadal symptoms. Based on total testosterone (TT), calculated free testosterone, and luteinizing hormone, five categories were identified: eugonadism, primary, secondary, normogonadotropic and compensated hypogonadism. Estimates of liver fibrosis were performed by aspartate aminotransferase (AST)-to-platelet ratio index (APRI) and Fibrosis-4 (FIB-4) scores. RESULTS: Hypogonadism was found in 32/107 patients (30.8%), with normogonadotropic (10/107, 9.3%) and compensated (17/107, 15.8%) being the most frequent forms. Patients with secondary/normogonadotropic hypogonadism had higher body mass index (BMI) (p < 0001). Patients with compensated hypogonadism had longer HIV infection duration (p = 0.031), higher APRI (p = 0.035) and FIB-4 scores (p = 0.008), and higher HCV co-infection. Univariate analysis showed a direct significant correlation between APRI and TT (p = 0.006) and SHBG (p = 0.002), and between FIB-4 and SHBG (p = 0.045). Multivariate analysis showed that SHBG was independently associated with both liver fibrosis scores. CONCLUSION: Overt and compensated hypogonadism are frequently observed among HIV-infected men. Whereas obesity is related to secondary hypogonadism, high SHBG levels, related to liver fibrosis degree and HCV co-infection, are responsible for compensated forms.


Assuntos
Infecções por HIV/complicações , Hipogonadismo/etiologia , Cirrose Hepática/etiologia , Aspartato Aminotransferases/sangue , Estudos de Coortes , Estudos Transversais , Infecções por HIV/epidemiologia , Humanos , Hipogonadismo/epidemiologia , Cirrose Hepática/epidemiologia , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/sangue
4.
HIV Med ; 21(8): 523-535, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32578947

RESUMO

OBJECTIVES: The aim of this study was to evaluate the factors that can influence an incomplete viral response (IVR) after acute and early HIV infection (AEHI). METHODS: This was a retrospective, observational study including patients with AEHI (Fiebig stages I-V) diagnosed between January 2008 and December 2014 at 20 Italian centres. IVR was defined by: (1) viral blip (51-1000 HIV-1 RNA copies/mL after achievement of < 50 HIV-1 RNA copies/mL); (2) virologic failure [> 1000 copies/mL after achievement of < 200 copies/mL, or ≥ 200 copies/mL after 24 weeks on an antiretroviral therapy (ART)]; (3) suboptimal viral response (> 50 copies/mL after 48 weeks on ART or two consecutive HIV-1 RNA levels with ascending trend during ART). Cox regression analysis was used to calculate the hazard ratios (HRs) and 95% confidence intervals (95% CIs) for IVR. RESULTS: In all, 263 patients were studied, 227 (86%) males, with a median [interquartile range (IQR)] age of 38 (30-46) years. During a median follow-up of 13.0 (5.7-31.1) months, 38 (14.4%) had IVR. The presence of central nervous system (CNS) symptoms was linked to a higher risk of IVR (HR = 4.70, 95% CI: 1.56-14.17), while a higher CD4/CD8 cell count ratio (HR = 0.13, 95% CI: 0.03-0.51 for each point increase) and first-line ART with three-drug regimens recommended by current guidelines (HR = 0.40, 95% CI: 0.18-0.91 compared with other regimens including four or five drugs, older drugs or non-standard backbones) were protective against IVR. CONCLUSIONS: Patients with lower CD4/CD8 ratio and CNS symptoms could be at a higher risk of IVR after AEHI. The use of recommended ART may be relevant for improving short-term viral efficacy in this group of patients.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Doenças do Sistema Nervoso Central/etiologia , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Doença Aguda , Adulto , Fármacos Anti-HIV/farmacologia , Contagem de Linfócito CD4 , Feminino , Infecções por HIV/sangue , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Humanos , Itália , Masculino , Pessoa de Meia-Idade , RNA Viral/genética , Análise de Regressão , Estudos Retrospectivos , Fatores de Risco , Falha de Tratamento , Carga Viral/efeitos dos fármacos
5.
Ann Hematol ; 99(8): 1741-1747, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32399706

RESUMO

To describe and compare the characteristics of necrotizing fasciitis (NF) in patients with and without haematological malignancy. All adult patients diagnosed with NF and treated at our hospital were included (January 2010-March 2019). Diagnosis was based on intraoperative findings or consistent clinical/radiological characteristics, and patients were classified as group A (with haematological malignancy) or group B (without haematological malignancy). Student's t (quantitative), Fisher's exact (qualitative), and Kaplan-Meyer tests were used for the statistical analysis. The study included 29 patients: 8 in group A and 21 in group B. All haematological patients had severe neutropenia (0.2 [0.02-0.5] ×109 cells/L; p < 0.001) and positive blood cultures (100% vs. 61.9%; p = 0.04) at diagnosis. Gram-negative bacilli NF was more common in group A (87.5% vs. 9.5%; p = 0.001), predominantly due to Escherichia coli (50% vs. 9.5%; p = 0.056). Surgical treatment was less common in haematological patients (5 [62.5%] vs. 21 [100%]; p = 0.015). Overall, 9 (31%) patients died: 4 (50%) in group A and 5 (23.8%) in group B (p = 0.17). The univariate analysis showed that mortality tended to be higher (OR 3.2; 95%CI 0.57-17.7; p = 0.17) and to occur earlier (2.2 ± 2.6 vs. 14.2 ± 19.9 days; p = 0.13) in haematological patients. The LRINEC index > 6 did not predict mortality in either group. In our study, NF in patients with haematological malignancies was mainly due to Gram-negative bacilli, associated to high and early mortality rates. In our experience, the LRINEC scale was not useful for predicting mortality.


Assuntos
Infecções por Escherichia coli/mortalidade , Escherichia coli , Fasciite Necrosante/mortalidade , Neoplasias Hematológicas/mortalidade , Neutropenia , Adulto , Idoso , Intervalo Livre de Doença , Infecções por Escherichia coli/terapia , Fasciite Necrosante/microbiologia , Fasciite Necrosante/terapia , Feminino , Neoplasias Hematológicas/microbiologia , Neoplasias Hematológicas/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Neutropenia/microbiologia , Neutropenia/terapia , Estudos Retrospectivos , Espanha/epidemiologia , Taxa de Sobrevida
6.
Immun Ageing ; 16: 26, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31636688

RESUMO

BACKGROUND: While immunosenescence, defined as reduced production of new lymphocytes, restriction of T-cell receptor repertoire and telomeres shortening, has been extensively evaluated in HIV-infected children and adults, no data about these parameters are available in perinatally-infected patients with very long-lasting HIV infection. METHODS: We compared thymic and bone marrow output, telomere length (measured by Real-Time PCR) and T-cell receptor repertoire (determined by spectratyping) of 21 perinatally HIV-infected subjects (with a median of 27 years of infection) with those of 19 age-matched non-perinatally HIV-infected patients and 40 healthy controls. All patients received a combined antiretroviral therapy. RESULTS: While thymic and bone marrow output were not different among the analyzed groups, telomere length in peripheral blood cells and T-cell receptor diversity were significantly lower in HIV-perinatally and non-perinatally infected individuals compared to healthy controls. CONCLUSIONS: In HIV-infected subjects, a normal thymic output together with a reduced telomere length and a restricted T-cell receptor repertoire could be explained by the shift of newly produced cells into memory subsets. This phenomenon may allow to control viral infection and maintain peripheral homeostasis.

7.
Environ Manage ; 64(6): 783-793, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31732774

RESUMO

Environmental Management Systems (EMS) based on international standard ISO 14001 are recognized as a tool to improve the environment and the sustainability of organizations. Green Chemistry (GC) seeks to reduce the use and generation of hazardous substances in chemical processes. This paper studies the relationship between EMS based on ISO 14001 and GC. We have analysed their similarities, difficulties, advantages, and synergies that can be developed with a joint implementation in general and in particular on university campuses. The results show that both disciplines have in common the philosophy of Continuous Improvement in the Processes (CIP) and that their joint application is possible, since each principle of GC are related to, at least, one clause of ISO 14001. It is shown that this joint application to different university areas can generate benefits, such as the reduction of hazardous waste and the promotion of green purchases, which favour the environmental improvement of universities. However, there are problems in their joint application related to the lack of specific knowledge and the difficulty of identifying products manufactured following the criteria of GC. Furthermore, a case study in the San Jorge University showing that both disciplines can be treated together is shown. Results were the following: seven GC initiatives (proposed by a small group of GC students) were submitted to the EMS office; only one was considered nonviable and two were implemented, achieving two main goals: Reduction of the environmental impact of laboratories and promotion of green purchasing in the laboratories of San Jorge University.


Assuntos
Resíduos Perigosos , Universidades , Comércio , Conservação dos Recursos Naturais , Humanos
10.
J Evol Biol ; 29(6): 1168-77, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26969911

RESUMO

Competition between spermatozoa of rival males to gain fertilizations has led to a wide array of modifications in sperm structure and function. Sperm cells of most muroid rodents have hook-shaped extensions in the apical-ventral tip of the head, but the function of this structure is largely unknown. These 'hooks' may facilitate aggregation of spermatozoa in so-called 'trains', as an adaptation to sperm competition, because sperm in trains may swim faster than free-swimming cells. However, there is controversy regarding the role of the hook in train formation, and in relation to whether it is selected by sperm competition. We examined spermatozoa from muroid rodents with varying levels of sperm competition to assess whether (i) sperm aggregates are common in these taxa, (ii) presence of a hook relates to the formation of sperm aggregations, and (iii) formation of sperm aggregations is explained by sperm competition. Our analyses in 25 muroid species revealed that > 92% of spermatozoa swim individually in all species, with the exception of the wood mouse, Apodemus sylvaticus, which has ~50% spermatozoa swimming freely. Species with hooked spermatozoa had higher sperm competition levels and longer sperm than species whose sperm lack a hook. Neither the presence of hook nor sperm competition levels were related to the percentage of sperm in aggregations. Thus, (i) sperm aggregates in muroid rodents are an exceptional trait found only in a few species, (ii) evolution of the sperm hook is associated to sperm competition levels, but (iii) the hook is unlikely to be related to the formation of sperm aggregates. The evolutionary significance of the sperm head hook thus remains elusive, and future studies should examine potential roles of this pervasive structure in sperm's hydrodynamic efficiency and sperm-female tract interactions.


Assuntos
Evolução Biológica , Espermatozoides , Animais , Movimento Celular , Feminino , Masculino , Camundongos , Murinae , Cabeça do Espermatozoide
11.
Clin Exp Immunol ; 180(2): 243-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25565222

RESUMO

Changes in blood natural killer (NK) cells, important players of the immune innate system, have been described in multiple sclerosis (MS). We studied percentages and total cell counts of different effector and regulatory NK cells in cerebrospinal fluid (CSF) of MS patients and other neurological diseases to gain clearer knowledge of the role of these cells in neuroinflammation. NK cell subsets were assessed by flow cytometry in CSF of 85 consecutive MS patients (33 with active disease and 52 with stable MS), 16 with other inflammatory diseases of the central nervous system (IND) and 17 with non-inflammatory neurological diseases (NIND). MS patients showed a decrease in percentages of different CSF NK subpopulations compared to the NIND group. However, absolute cell counts showed a significant increase of all NK subsets in MS and IND patients, revealing that the decrease in percentages does not reflect a real reduction of these immune cells. Remarkably, MS patients showed a significant increase of regulatory/effector (CD56(bright) /CD56(dim) ) NK ratio compared to IND and NIND groups. In addition, MS activity associated with an expansion of NK T cells. These data show that NK cell subsets do not increase uniformly in all inflammatory neurological disease and suggest strongly that regulatory CD56(bright) and NK T cells may arise in CSF of MS patients as an attempt to counteract the CNS immune activation characteristic of the disease.


Assuntos
Células Matadoras Naturais , Esclerose Múltipla , Células T Matadoras Naturais , Antígeno CD56/líquido cefalorraquidiano , Antígeno CD56/imunologia , Feminino , Citometria de Fluxo , Humanos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Contagem de Linfócitos , Masculino , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Células T Matadoras Naturais/imunologia , Células T Matadoras Naturais/patologia
12.
HIV Med ; 16(7): 412-20, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25959419

RESUMO

OBJECTIVES: The aims of this study were to identify temporal trends in the incidence of sexually transmitted diseases (STDs) in a cohort of HIV-infected people and to evaluate factors associated with the risk of a new STD diagnosis. METHODS: All HIV-infected patients in the Icona Foundation Study cohort enrolled after 1998 were included in this study. STD incidence rates (IRs) were calculated and stratified by calendar period. Predictors of STDs were identified using a Poisson regression model with sandwich estimates for standard errors. RESULTS: Data for 9168 participants were analysed [median age 37.3 (range 18-81) years; 74% male; 30% men who have sex with men (MSM)]. Over 46 736 person-years of follow-up (PYFU), 996 episodes of STDs were observed [crude IR 21.3/1000 PYFU; 95% confidence interval (CI) 20.0-22.6/1000 PYFU]. In multivariable Poisson regression analysis, MSM [rate ratio (RR) 3.03; 95% CI 2.52-3.64 versus heterosexuals], calendar period (RR 1.67; 95% CI 1.42-1.97 for 2008-2012 versus 1998-2002), HIV RNA > 50 HIV-1 RNA copies/mL (RR 1.44; 95% CI 1.19-1.74 versus HIV RNA ≤ 50 copies/mL) and a current CD4 count < 100 cells/µL (RR 4.66; 95% CI 3.69-5.89; P < 0.001 versus CD4 count > 500 cells/µL) were associated with an increased risk of STDs. In contrast, older age (RR 0.82 per 10 years older; 95% CI 0.77-0.89) and being currently on ART (RR 0.38; 95% CI 0.33-0.45) compared with being ART-naïve or on a treatment interruption were associated with a lower risk of developing STDs. CONCLUSIONS: An increase in the incidence of STDs was observed in more recent years. Interventions to prevent STDs and potential spread of HIV should target the younger population, MSM and people currently not receiving ART.


Assuntos
Soropositividade para HIV/epidemiologia , Comportamento Sexual/estatística & dados numéricos , Infecções Sexualmente Transmissíveis/transmissão , Adulto , Distribuição por Idade , Idoso , Contagem de Linfócito CD4 , Feminino , Soropositividade para HIV/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Incidência , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Comportamento Sexual/psicologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Infecções Sexualmente Transmissíveis/psicologia , Carga Viral
13.
Osteoporos Int ; 26(10): 2529-58, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26070300

RESUMO

UNLABELLED: This article reports a taxonomic classification of rare skeletal diseases based on metabolic phenotypes. It was prepared by The Skeletal Rare Diseases Working Group of the International Osteoporosis Foundation (IOF) and includes 116 OMIM phenotypes with 86 affected genes. INTRODUCTION: Rare skeletal metabolic diseases comprise a group of diseases commonly associated with severe clinical consequences. In recent years, the description of the clinical phenotypes and radiographic features of several genetic bone disorders was paralleled by the discovery of key molecular pathways involved in the regulation of bone and mineral metabolism. Including this information in the description and classification of rare skeletal diseases may improve the recognition and management of affected patients. METHODS: IOF recognized this need and formed a Skeletal Rare Diseases Working Group (SRD-WG) of basic and clinical scientists who developed a taxonomy of rare skeletal diseases based on their metabolic pathogenesis. RESULTS: This taxonomy of rare genetic metabolic bone disorders (RGMBDs) comprises 116 OMIM phenotypes, with 86 affected genes related to bone and mineral homeostasis. The diseases were divided into four major groups, namely, disorders due to altered osteoclast, osteoblast, or osteocyte activity; disorders due to altered bone matrix proteins; disorders due to altered bone microenvironmental regulators; and disorders due to deranged calciotropic hormonal activity. CONCLUSIONS: This article provides the first comprehensive taxonomy of rare metabolic skeletal diseases based on deranged metabolic activity. This classification will help in the development of common and shared diagnostic and therapeutic pathways for these patients and also in the creation of international registries of rare skeletal diseases, the first step for the development of genetic tests based on next generation sequencing and for performing large intervention trials to assess efficacy of orphan drugs.


Assuntos
Doenças do Desenvolvimento Ósseo/classificação , Doenças do Desenvolvimento Ósseo/genética , Doenças Ósseas Metabólicas/classificação , Doenças Ósseas Metabólicas/genética , Doenças do Desenvolvimento Ósseo/diagnóstico , Doenças do Desenvolvimento Ósseo/metabolismo , Doenças Ósseas Metabólicas/diagnóstico , Doenças Ósseas Metabólicas/metabolismo , Humanos , Osteoblastos/fisiologia , Osteoclastos/fisiologia , Osteócitos/fisiologia , Fenótipo , Proteoglicanas/metabolismo , Doenças Raras/classificação , Doenças Raras/diagnóstico , Doenças Raras/genética , Doenças Raras/metabolismo
14.
J Evol Biol ; 28(10): 1816-27, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26190170

RESUMO

Post-copulatory sexual selection, in the form sperm competition, has influenced the evolution of several male reproductive traits. However, theory predicts that sperm competition would lead to trade-offs between numbers and size of spermatozoa because increased costs per cell would result in a reduction of sperm number if both traits share the same energetic budget. Theoretical models have proposed that, in large animals, increased sperm size would have minimal fitness advantage compared with increased sperm numbers. Thus, sperm numbers would evolve more rapidly than sperm size under sperm competition pressure. We tested in mammals whether sperm competition maximizes sperm numbers and size, and whether there is a trade-off between these traits. Our results showed that sperm competition maximizes sperm numbers in eutherian and metatherian mammals. There was no evidence of a trade-off between sperm numbers and sperm size in any of the two mammalian clades as we did not observe any significant relationship between sperm numbers and sperm size once the effect of sperm competition was taken into account. Maximization of both numbers and size in mammals may occur because each trait is crucial at different stages in sperm's life; for example size-determined sperm velocity is a key determinant of fertilization success. In addition, numbers and size may also be influenced by diverse energetic budgets required at different stages of sperm formation.


Assuntos
Contagem de Espermatozoides , Espermatozoides/citologia , Humanos , Masculino , Tamanho do Órgão , Testículo/citologia
15.
Int J Environ Health Res ; 25(3): 277-87, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25104053

RESUMO

The aim of this study was to determine the temperature threshold that triggers an increase in heat-induced mortality in Zaragoza, Spain to determine the impact of extreme heat on mortality and in-hospital cost. A longitudinal ecological study was conducted according to an autoregressive integrated moving average model of a time series for daily deaths and to determine the relative risk of mortality for each degree that the temperature threshold was exceeded. Mortality showed a statistically significant increase when the daily maximum temperature exceeded 38 °C. A Relative Risk was 1.28 with a 95 % confidence interval (95 %CI:1.08-1.57) This threshold temperature didn't change over time. A total of 107 (95 %CI:42-173) heat-attributable deaths were estimated for the period 2002-2006, and the in-hospital estimated cost of these deaths reach € 426,087(95 %CI.€ 167,249-€ 688,907). The articulation of preventive measures to minimize the impact of extreme heat on human health is necessary because of the mortality-temperature relationship.


Assuntos
Calor Extremo/efeitos adversos , Mortalidade , Análise por Conglomerados , Temperatura Alta/efeitos adversos , Humanos , Raios Infravermelhos , Tempo de Internação/economia , Estudos Longitudinais , Análise Multivariada , Espanha/epidemiologia
16.
Osteoporos Int ; 25(9): 2263-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25056799

RESUMO

UNLABELLED: This study investigated the bone of HIV patients both in terms of quantity and quality. It was found that HIV-infected patients did fracture independently of the degree of bone demineralization as in other forms of secondary osteoporosis. INTRODUCTION: We aimed to determine the prevalence of vertebral fractures (VFs) in HIV patients who were screened by bone mineral density (BMD) and to explore possible factors associated with VFs. METHODS: This is a cross-sectional study that included HIV-infected patients recruited in the Clinic of Infectious and Tropical Diseases and that underwent BMD measurement by dual-energy X-ray absorptiometry (DXA) at the lumbar spine and hip (Lunar Prodigy, GE Healthcare). For the assessment of VFs, anteroposterior and lateral X-ray examinations of the thoracic and lumbar spines were performed and were centrally digitized. Logistic regression models were used in the statistical analysis of factors associated with VFs. RESULTS: One hundred thirty-one consecutive patients with HIV infection (93 M, 38 F, median age 51 years; range, 36-75) underwent BMD measurement: 25.2 % of patients showed normal BMD, while 45 % were osteopenic and 29.7 % osteoporotic. Prevalence of low BMD (osteopenia and osteoporosis) was higher in females as compared to males (90 vs 69 %) with no significant correlation with age and body mass index. VFs occurred more frequently in patients with low BMD as compared to patients with normal BMD (88.5 vs. 11.4 %; p < 0.001) without any significant difference between osteopenia and osteoporosis (43 vs. 46 %; p = 0.073). VFs were significantly associated with older age and previous AIDS events. CONCLUSIONS: These results suggest a BMD <-1 threshold to identify patients at risk of skeletal fragility and, therefore, good candidates for morphometric evaluation of spine X-ray in line with other forms of secondary osteoporosis with impaired bone quality.


Assuntos
Densidade Óssea/fisiologia , Infecções por HIV/complicações , Fraturas por Osteoporose/virologia , Fraturas da Coluna Vertebral/virologia , Absorciometria de Fóton/métodos , Adulto , Idoso , Doenças Ósseas Metabólicas/diagnóstico , Doenças Ósseas Metabólicas/fisiopatologia , Doenças Ósseas Metabólicas/virologia , Contagem de Linfócito CD4 , Estudos Transversais , Feminino , Infecções por HIV/imunologia , Infecções por HIV/fisiopatologia , Articulação do Quadril/fisiopatologia , Humanos , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico , Osteoporose/fisiopatologia , Osteoporose/virologia , Fraturas por Osteoporose/fisiopatologia , Fraturas da Coluna Vertebral/fisiopatologia
17.
J Evol Biol ; 27(1): 55-62, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24251445

RESUMO

The sperm membrane is a key structure affecting sperm function and thus reproductive success. Spermatozoa are highly specialized and differentiated cells that undergo a long series of processes in the male and female reproductive tracts until they reach the site of fertilization. During this transit, the sperm membrane is prone to damage such as lipid peroxidation. The characteristics and performance of the sperm membrane are strongly determined by the fatty-acid composition of membrane phospholipids. Polyunsaturated fatty-acids (PUFAs) are the most prone to lipid peroxidation. Lipid peroxidation and other types of oxidative damage increase with higher metabolism and with higher levels of sperm competition due to the increased ATP production to fuel higher sperm velocities. Consequently, we hypothesized that, in order to avoid oxidative damage, and the ensuing impairment of sperm function, sperm cells exhibit a negative relationship between PUFA content and mass-specific metabolic rate (MSMR). We also hypothesized that higher sperm competition leads to a reduction in the proportion of sperm PUFAs. We performed a comparative study in mammals and found that high MSMR and high levels of sperm competition both promote a decrease in the proportion of PUFAs that are more prone to lipid peroxidation. The negative relationship between MSMR and these PUFAs in sperm cells is surprising, because a positive relationship is found in all other cell types so far investigated. Our results support the idea that the effects of MSMR and sperm competition on sperm function can operate at very different levels.


Assuntos
Metabolismo Energético , Ácidos Graxos Insaturados/metabolismo , Espermatozoides/metabolismo , Animais , Bovinos , Cricetinae , Cães , Humanos , Masculino , Camundongos , Coelhos , Ratos
18.
J Helminthol ; 88(4): 459-67, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23742745

RESUMO

Bisphosphonates have been proposed as pharmacological agents against parasite and cancer cell growth. The effect of these compounds on helminthic cell viability and acellular compartment morphology, however, has not yet been studied. The effects of different types of bisphosphonates, namely etidronate (EHDP), pamidronate (APD), alendronate (ABP), ibandronate (IB) and olpadronate (OPD), and their interaction with amiloride, 1,25-dihydroxycholecalciferol (D3) and proline were evaluated on a cell line derived from bovine Echinococcus granulousus protoscoleces (EGPE) that forms cystic colonies in agarose. The EGPE cell line allowed testing the effect of bisphosphonates alone and in association with other compounds that could modulate calcium apposition/deposition, and were useful in measuring the impact of these compounds on cell growth, cystic colony formation and calcium storage. Decreased cell growth and cystic colony formation were found with EHDP, IB and OPD, and increased calcium storage with EHDP only. Calcium storage in EGPE cells appeared to be sensitive to the effect of amiloride, D3 and proline. Proline decreased calcium storage and increased colony formation. Changes in calcium storage may be associated with degenerative changes of the cysts, as shown in the in vitro colony model and linked to an adenosine triphosphate (ATP) decrease. In conclusion, bisphosphonates could be suitable tempering drugs to treat cestode infections.


Assuntos
Trifosfato de Adenosina/metabolismo , Cálcio/metabolismo , Difosfonatos/farmacologia , Echinococcus granulosus/citologia , Prolina/farmacologia , Animais , Bovinos , Técnicas de Cultura de Células , Linhagem Celular , Relação Dose-Resposta a Droga , Fatores de Tempo
19.
HIV Med ; 14(8): 481-90, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23560682

RESUMO

OBJECTIVES: The aim of the study was to investigate the incidence of AIDS-defining cancers (ADCs) and virus-related and non-virus-related non-AIDS-defining cancers (NADCs) in HIV-infected patients compared with the general population, and to assess the risk factors associated with these malignancies. METHODS: We performed a retrospective cohort study for the period from 1999 to 2009 of HIV-infected patients residing in the Local Health Authority of Brescia (northern Italy). Observed cancers in patients with HIV infection were compared with expected cancers in the population living in the same area using standardized incidence ratios (SIRs). Risk factors were assessed using Poisson regression analysis. RESULTS: A total of 5090 HIV-infected patients were included in the study, with 32 390 person-years of follow-up. We recorded 416 tumours in 390 HIV-infected patients. Two hundred of these (48.1%) were ADCs, 138 (33.2%) were non-virus-related NADCs and 78 (18.7%) were virus-related NADCs. An increased risk (SIR = 4.2) of cancers overall was found in HIV-infected patients. A large excess of ADCs (SIR = 31.0) and virus-related NADCs (SIR = 12.3) was observed in HIV-infected patients, while the excess risk for non-virus-related NADCs was small (SIR = 1.6). The highest SIRs were observed for Kaposi sarcoma among ADCs and for Hodgkin lymphoma among virus-related NADCs. Conversely, among non-virus-related NADCs, SIRs for a broad range of malignancies were close to unity. In multivariate analysis, increasing age and CD4 cell count < 50 cells/µL were the only factors independently associated with all cancers. CONCLUSIONS: Among HIV-infected people there was an excess of ADCs and also of NADCs, particularly those related to viral infections. Ageing and severe immunodeficiency were the strongest predictors.


Assuntos
Infecções por HIV/epidemiologia , Linfoma Relacionado a AIDS/epidemiologia , Neoplasias/epidemiologia , Síndrome da Imunodeficiência Adquirida/complicações , Adulto , Fatores Etários , Idoso , Contagem de Linfócito CD4 , Estudos de Coortes , Comorbidade , Feminino , Doença de Hodgkin/epidemiologia , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Distribuição de Poisson , Análise de Regressão , Estudos Retrospectivos , Fatores de Risco , Sarcoma de Kaposi/epidemiologia , Adulto Jovem
20.
J Musculoskelet Neuronal Interact ; 13(2): 185-94, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23728105

RESUMO

Some pharmacologic effects on bone modeling may not be evident in studies of remodeling skeletons. This study analyzes some effects of olpadronate on cortical bone modeling and post-yield properties in femurs diaphyses (virtually only-modeling bones) of young rats by mid-diaphyseal pQCT scans and bending tests. We studied 20/22 male/female animals traetad orally with olpadronate (45-90 mg/kg/d, 3 months) and 8/9 untreated controls. Both OPD doses enhanced diaphyseal cross-sectional moments of inertia (CSMI) with no change in cortical vBMD and elastic modulus. Yield stiffness and strength were mildly increased. Post-yield strength, deflection and energy absorption were strikingly enhanced. Ultimate strength was enhanced mainly because of effects on bone mass/geometry and post-yield properties. The large improvement of post-yield properties could be explained by improvements in bone geometry. Improvements in bone mass/geometry over weight-bearing needs suggest an enhanced modeling-related response to mechanical stimuli. Effects on tissue microstructural factors (not measured) could not be excluded. Results reveal novel olpadronate effects on bone strength and toughness unrelated to tissue mineralization and stiffness, even at high doses. Further studies could establish whether this could also occur in modeling-remodeling skeletons. If so, they could counteract the negative impact of anti-remodeling effects of bisphosphonates on bone strength.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Remodelação Óssea/efeitos dos fármacos , Calcificação Fisiológica/efeitos dos fármacos , Difosfonatos/farmacologia , Análise de Variância , Animais , Fenômenos Biomecânicos , Densidade Óssea/efeitos dos fármacos , Diáfises/anatomia & histologia , Diáfises/fisiologia , Relação Dose-Resposta a Droga , Módulo de Elasticidade , Elasticidade , Feminino , Fêmur/anatomia & histologia , Fêmur/fisiologia , Masculino , Ratos , Ratos Wistar , Caracteres Sexuais , Software , Tomografia
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