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1.
Osteoporos Int ; 32(12): 2461-2472, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34097127

RESUMO

We analyzed polymorphism of the ALPL gene in patients with low serum levels of tissue-nonspecific alkaline phosphatase (TNAP). The presence of three or more of the less frequent alleles of ALPL polymorphisms was associated with significantly lower TNAP serum level and higher frequencies of metatarsal fractures, which may help confirm a clinical suspicion of adult hypophosphatasia. INTRODUCTION: Alkaline phosphatases (ALPs) are membrane-bound enzymes that hydrolyze monophosphate esters at a high pH (pH 8-10). Inorganic pyrophosphate, pyridoxal 5-phosphate, the activated form of vitamin B6 (PLP), and phosphoethanolamine (PEA), are natural substrates of ALPs. Hypophosphatasia (HPP, OMIM 146300, 241500, 241510) is a heterogeneous rare metabolic bone disease caused by loss-of-function mutations in the tissue-nonspecific alkaline phosphatase gene (ALPL; MIM 171760) with a deficiency of TNAP. Clinical presentation of HPP in adults demonstrated a wide range of manifestations, many of which are nonspecific. In the present study, we screened the polymorphic genetic variants of ALPL in 56 subjects presenting low serum levels of TNAP and/or other clinical signs of adult HPP in order to evaluate a possible role of polymorphic variants in the diagnosis and management of HPP in adults. METHODS: Genomic DNA was extracted from peripheral blood and ALPL gene was sequenced by PCR-based Sanger technique. RESULTS: Fourteen different polymorphic variants were found in the study population. A lower serum level of TNAP and higher frequencies of metatarsal fractures were observed in patients bearing three or more of the minor frequency alleles (MFAs) of the ALPL polymorphic variants. The presence of some MFAs, mostly as a contemporary presence of three or more of them, was found to be mainly represented in patients having both a significantly lower level of TNAP and a higher level of vitamin B6. CONCLUSION: The genetic analysis and presence of some polymorphic variants may be an instrument to confirm clinical and biochemical data, consider adult HPP, and help clinicians be cautious in the administration of anti-reabsorption drugs.


Assuntos
Hipofosfatasia , Adulto , Fosfatase Alcalina/genética , Alelos , Humanos , Hipofosfatasia/genética , Mutação , Fosfato de Piridoxal
2.
Phys Rev Lett ; 122(6): 067002, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30822056

RESUMO

Optimally doped cuprate are characterized by the presence of superconducting fluctuations in a relatively large temperature region above the critical transition temperature. We reveal here that the effect of thermal disorder, which decreases the condensate phase coherence at equilibrium, can be dynamically contrasted by photoexcitation with ultrashort midinfrared pulses. In particular, our findings reveal that light pulses with photon energy comparable to the amplitude of the superconducting gap and polarized in plane along the copper-copper direction can dynamically enhance the optical response associated with the onset of superconductivity. We propose that this effect can be rationalized by an effective d-wave BCS model, which reveals that midinfrared pulses result in a transient increase of the phase coherence.

3.
Osteoporos Int ; 28(11): 3239-3249, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28815282

RESUMO

RATIONALE: Calcidiol can be employed to correct vitamin D deficiency. MAIN RESULTS: Calcidiol administered at daily and weekly regimens over a period of 3 months was able to successfully raise 25-hydroxyvitamin D levels without altering other markers related to bone and mineral metabolism. SIGNIFICANCE: Calcidiol supplementation is effective and safe. INTRODUCTION: The correction of vitamin D status is necessary to maintain an optimal mineral and skeletal homeostasis. Despite cholecalciferol (vitamin D3) is the most commonly used drug for vitamin D supplementation, the more hydrophilic compound calcidiol (25-hydroxyvitamin D3) can be employed at daily, weekly, and monthly regimens to reach in the short term the target levels of serum 25-hydroxyvitamin D [25(OH)D]. In the administration of different doses of calcidiol pharmacokinetic study (ADDI-D study), the efficacy and safety of daily and weekly dosages of calcidiol were tested. METHODS: A total of 87 Caucasian, community-dwelling, postmenopausal women, aged 55 years or older, with vitamin D inadequacy (serum 25(OH)D levels <30 ng/ml, with mean 25(OH)D below 20 ng/ml, namely 16.5 ± 7.5 ng/ml) were randomized to receive three different dosages of calcidiol: 20 µg/day, 40 µg/day, and 125 µg/week for 3 months. The attained level of serum 25(OH)D was selected as primary endpoint to assess efficacy, while other parameters of mineral metabolism, (serum calcium, parathyroid hormone, phosphate, FGF23, urinary calcium, and markers of bone turnover) were assessed as secondary endpoints to establish safety. RESULTS: In all the three groups, serum 25(OH)D values significantly and promptly rose and plateaued above the 30 ng/ml threshold remaining within safety interval after 14 days of treatment, with similar efficacy for the similar daily and weekly dose regimens. The different dosages were also equally effective in controlling secondary hyperparathyroidism. No significant changes in calcium and phosphate metabolism and in bone turnover markers were observed for any of the treatments, confirming the safety of this compound. CONCLUSIONS: The results of this study demonstrate the short- and mid-term efficacy and safety on core parameters of mineral metabolism of different daily or weekly dosages of calcidiol when used to treat vitamin D inadequacy or deficiency in postmenopausal women. Further studies are needed to assess falls as primary outcome of calcidiol supplementation.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Calcifediol/administração & dosagem , Deficiência de Vitamina D/tratamento farmacológico , Biomarcadores/sangue , Conservadores da Densidade Óssea/efeitos adversos , Conservadores da Densidade Óssea/uso terapêutico , Remodelação Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Calcifediol/efeitos adversos , Calcifediol/uso terapêutico , Cálcio/metabolismo , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Fator de Crescimento de Fibroblastos 23 , Humanos , Pessoa de Meia-Idade , Fosfatos/sangue , Pós-Menopausa/metabolismo , Pós-Menopausa/fisiologia , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/fisiopatologia
4.
Mol Phylogenet Evol ; 98: 358-72, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26926944

RESUMO

Little is known about the evolutionary history of Helix, despite the fact that it includes the largest land snails in the western Palaearctic, some of which (e.g. H. pomatia Linnaeus, 1758) are valuable human food. We compared two groups of Helix with apparently contrasting evolutionary histories: the widespread species H. pomatia and the group distributed along the Italian Apennine chain, a relatively unknown set of species with a restricted distribution over a range of altitudes. To reconstruct the evolutionary trajectories of these two groups, we analysed morphological (shell and genitalia) and molecular characters (mitochondrial and nuclear markers) in a total of 59 populations from northern and central Europe (H. pomatia) and along the Apennine chain (various species). We also reconstructed the phylogeny and the evolutionary history of the genus by combining our data with that currently available in the literature. We found that spatial changes did not merely imply fragmentation of populations, but also implied environmental changes (woodlands vs. grasslands) that may have triggered the observed phenotypic diversification. We also found that Anatolia is the ancestral range of Helix and is therefore an important area for the Palaearctic diversity. The results provide insights into the evolutionary history of species richness and more generally into the processes that may have shaped the distribution and diversification of these organisms across Europe and the peri-Mediterranean area.


Assuntos
Filogenia , Caramujos/classificação , Exoesqueleto/anatomia & histologia , Animais , Núcleo Celular/genética , Itália , Região do Mediterrâneo , Mitocôndrias/genética , Fenótipo , Filogeografia , Caramujos/anatomia & histologia , Caramujos/genética
5.
J Eur Acad Dermatol Venereol ; 30(3): 413-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26446299

RESUMO

BACKGROUND: The sub-optimal diagnostic accuracy for melanoma leads to excise a high number of benign lesions, with consequent costs. Reflectance confocal microscopy (RCM) improves diagnostic specificity, thus possibly inducing a reduction in unnecessary excisions and related costs. OBJECTIVE: To estimate the influence of RCM on number of benign lesions needed to excise (NNE) a melanoma, in term of clinical outcomes and costs per patient. PATIENTS AND METHODS: Skin neoplasms excised by the dermatology public service in the Province of Modena were retrieved form centralized pathology database. Differences in NNE between the territorial service (using dermoscopy only) and the University Hospital (adding also RCM to the patients' workflow) were calculated and cost analysis was performed through a micro-costing approach. RESULTS: A large reduction in benign lesions excised at University Hospital was evident, leading to NNE of 6.25 for University Hospital, compared to 19.41 for Territorial Dermatology. Since 4320 unnecessary excisions can be saved every million inhabitants, an overall yearly saving of over 280,000 Eur can be expected from the use of RCM. CONCLUSIONS: The systematic use of RCM was dramatically affecting the number of benign lesions excised, and this can be translated in a significant cost-benefit advantage.


Assuntos
Dermatologia/economia , Melanoma/patologia , Microscopia Confocal/economia , Neoplasias Cutâneas/patologia , Análise Custo-Benefício , Dermoscopia/economia , Humanos , Estudos Retrospectivos
6.
Calcif Tissue Int ; 96(5): 438-52, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25899975

RESUMO

Human disorders of phosphate (Pi) handling and skeletal mineralization represent a group of rare bone diseases. One of these disease is tumoral calcinosis (TC). In this study, we present the case of a patient with TC with a new GALNT3 gene mutation. We also performed functional studies using an in vitro cellular model. Genomic DNA was extracted from peripheral blood collected from a teenage Caucasian girl affected by TC, and from her parents. A higher capability to form mineralization nodules in vitro was found in human preosteoblastic cells of mutant when compared to wild-type controls. We found a novel homozygous inactivating splice site mutation in intron I (c.516-2a>g). A higher capability to form mineralization nodules in vitro was found in the mutant cells in human preosteoblastic cells when compared to wild-type controls. Understanding the functional significance and molecular physiology of this novel mutation will help to define the role of FGF23 in the control of Pi homeostasis in normal and in pathological conditions.


Assuntos
Calcinose/genética , Hiperostose Cortical Congênita/genética , Hiperfosfatemia/genética , Mutação , N-Acetilgalactosaminiltransferases/genética , Osteoblastos/patologia , Sequência de Bases , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Criança , Feminino , Fator de Crescimento de Fibroblastos 23 , Citometria de Fluxo , Humanos , Dados de Sequência Molecular , Linhagem , Reação em Cadeia da Polimerase , Células-Tronco/patologia , Polipeptídeo N-Acetilgalactosaminiltransferase
7.
J Membr Biol ; 247(9-10): 1043-51, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24898094

RESUMO

Amphipols (APols) are polymeric surfactants that keep membrane proteins (MPs) water-soluble in the absence of detergent, while stabilizing them. They can be used to deliver MPs and other hydrophobic molecules in vivo for therapeutic purposes, e.g., vaccination or targeted delivery of drugs. The biodistribution and elimination of the best characterized APol, a polyacrylate derivative called A8-35, have been examined in mice, using two fluorescent APols, grafted with either Alexa Fluor 647 or rhodamine. Three of the most common injection routes have been used, intravenous (IV), intraperitoneal (IP), and subcutaneous (SC). The biodistribution has been studied by in vivo fluorescence imaging and by determining the concentration of fluorophore in the main organs. Free rhodamine was used as a control. Upon IV injection, A8-35 distributes rapidly throughout the organism and is found in most organs but the brain and spleen, before being slowly eliminated (10-20 days). A similar pattern is observed after IP injection, following a brief latency period during which the polymer remains confined to the peritoneal cavity. Upon SC injection, A8-35 remains essentially confined to the point of injection, from which it is only slowly released. An interesting observation is that A8-35 tends to accumulate in fat pads, suggesting that it could be used to deliver anti-obesity drugs.


Assuntos
Sistemas de Liberação de Medicamentos , Especificidade de Órgãos/fisiologia , Polímeros/administração & dosagem , Polímeros/farmacocinética , Propilaminas/administração & dosagem , Propilaminas/farmacocinética , Tecido Adiposo/metabolismo , Animais , Feminino , Injeções Intraperitoneais , Injeções Intravenosas , Injeções Subcutâneas , Taxa de Depuração Metabólica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Distribuição Tecidual
8.
Br J Dermatol ; 171(5): 1006-13, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23909951

RESUMO

BACKGROUND: Small malignant melanomas (MMs) are usually MMs in an initial growth phase, deserving attention by the clinician aiming at an early diagnosis. OBJECTIVES: To identify clues for early diagnosis of small MMs, by comparing the dermoscopic features of MMs < 4 mm (micromelanomas) with those of larger MMs. METHODS: Our database consists of dermoscopic images of 482 MMs, which have been retrieved and measured digitally. The ABCD (asymmetry, border, colour, dimension) and 7-point criteria were evaluated for the whole database by three expert dermoscopists, whereas the main dermoscopic pattern was assessed only for micromelanomas. The dermoscopic aspects were correlated to clinical and histological features. RESULTS: Most 7-point and ABCD scores, and criteria referring to micromelanomas, differed from those of the MM database as a whole. Lesion asymmetry, number of colours, blue-whitish veil, atypical vessels, irregular globules/dots and regression increased according to MM diameter. An inverse trend was observed for atypical network and irregular pigmentation, which were more frequently observed in micromelanomas than in larger ones. Among the 22 micromelanomas, 12 lesions were in situ, whereas the other 10 were 0·2-2 mm thick. The clinical and dermoscopic characteristics of the two groups were similar. CONCLUSIONS: Micromelanomas are not a rarity. However, the clinician should be aware of the fact that the majority of them lack most of the dermoscopic features presented by larger lesions.


Assuntos
Dermoscopia/métodos , Melanoma/patologia , Neoplasias Cutâneas/patologia , Adolescente , Adulto , Idoso , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carga Tumoral
9.
Mol Ecol ; 22(1): 170-86, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23163429

RESUMO

The lively debate about speciation currently focuses on the relative importance of factors driving population differentiation. While many studies are increasingly producing results on the importance of selection, little is known about the interaction between drift and selection. Moreover, there is still little knowledge on the spatial-temporal scales at which speciation occurs, that is, arrangement of habitat patches, abruptness of habitat transitions, climate and habitat changes interacting with selective forces. To investigate these questions, we quantified variation on a fine geographical scale analysing morphological (shell) and genetic data sets coupled with environmental data in the land snail Murella muralis, endemic to the Mediterranean island of Sicily. Analysis of a fragment of the mitochondrial DNA cytochrome oxidase I gene (COI) and eight nuclear microsatellite loci showed that genetic variation is highly structured at a very fine spatial scale by local palaeogeographical events and historical population dynamics. Molecular clock estimates, calibrated here specifically for Tyrrhenian land snails, provided a framework of palaeogeographical events responsible for the observed geographical variations and migration routes. Finally, we showed for the first time well-documented lines of evidence of selection in the past, which explains divergence of land snail shell shapes. We suggest that time and palaeogeographical history acted as constraints in the progress along the ecological speciation continuum. Our study shows that testing for correlation among palaeogeography, morphology and genetic data on a fine geographical scale provides information fundamental for a detailed understanding of ecological speciation processes.


Assuntos
Especiação Genética , Variação Genética , Caramujos/genética , Exoesqueleto/anatomia & histologia , Animais , Núcleo Celular/genética , DNA Mitocondrial/genética , Meio Ambiente , Geografia , Haplótipos , Filogenia , Análise de Sequência de DNA , Sicília , Caramujos/anatomia & histologia
12.
G Chir ; 32(3): 132-4, 2011 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-21453592

RESUMO

INTRODUCTION: Multiple endocrine neoplasia syndromes (MEN) are genetic disease with many pathologic models. MEN 2B is a autosomal dominant syndrome characterized by medullary thyroid carcinoma, pheochromocytoma, mucosal ganglioneuromatosis and marfanoid habitus. Laparoscopic surgery is the gold standard for the treatment of pheochromocytoma. CASE REPORT: Woman 25 years old, suffering from medullary thyroid carcinoma in MEN 2B syndrome, underwent total thyroidectomy, with emptying of the lymphonodal central and lateral cervical (bilaterally) compartments and radioreceptor therapy. The patient was then submitted to four plastic surgery for cervical keloid. In January 2010, follow-up blood and instrumental tests show, in the lower portion of left adrenal gland, a round lesion, with smooth margins 17 mm diameter, attributable to pheochromocytoma. In March 2010 the patient underwent laparoscopic surgery for left adrenalectomy. DISCUSSION: The benefits of laparoscopic adrenalectomy for a single lesion are well documented in the literature; this type of intervention is indicated in cases of pheochromocytoma in patients with MEN 2B. Our case demonstrates the feasibility of this technique.


Assuntos
Neoplasias das Glândulas Suprarrenais/cirurgia , Adrenalectomia/métodos , Laparoscopia , Neoplasia Endócrina Múltipla Tipo 2b , Neoplasias Primárias Múltiplas , Feocromocitoma/cirurgia , Adulto , Feminino , Humanos , Laparoscopia/métodos
13.
Br J Dermatol ; 163(2): 302-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20426776

RESUMO

BACKGROUND: By dermoscopy, regression structures are substantially defined by the presence of white and blue areas in the lesion image. As fibrosis and melanosis are often seen in malignant melanoma (MM), the presence of dermoscopic signs of regression may represent a clue for the diagnosis of malignancy. OBJECTIVES: To assess the frequency and extent of dermoscopic signs of regression in melanoma in situ (MIS) and to describe its dermoscopic features. METHODS: Dermoscopic images of 85 MIS, 85 invasive MMs and 85 dermoscopically equivocal lesions with a histological diagnosis of naevus were evaluated by three dermatologists, who assessed the presence of 11 parameters of regression. RESULTS: The number of regression parameters per lesion increased according to melanoma thickness. White areas, the grey-blue veil and widespread blue areas were more frequent in invasive MMs than in the other two lesion groups, whereas light brown areas and regression of dermoscopic structures were more frequent in MIS. Peppering was observable in the same percentage of MIS and invasive MMs. Blue areas were more frequently structureless in equivocal lesions and invasive MMs, whereas the reticular pattern prevailed in MIS. CONCLUSIONS: Frequency, morphology, extent and distribution of regression vary according to melanoma thickness and diameter. Lesions with reticular blue regression and light brown areas should undergo surgical excision for the suspicion of MIS. Moreover, the identification of the reticular pattern of blue regression can be considered a significant discriminator and a reliable predictor of MIS.


Assuntos
Dermoscopia/métodos , Melanoma/patologia , Nevo Pigmentado/patologia , Pigmentação , Neoplasias Cutâneas/patologia , Adulto , Idoso , Biomarcadores/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Sensibilidade e Especificidade
14.
J Eur Acad Dermatol Venereol ; 24(3): 317-28, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19732254

RESUMO

BACKGROUND: The diagnosis of atopic dermatitis (AD) is made using evaluated clinical criteria. Management of AD must consider the symptomatic variability of the disease. METHODS: EADV eczema task force developed its guideline for atopic dermatitis diagnosis and treatment based on literature review and repeated consenting group discussions. RESULTS AND DISCUSSION: Basic therapy relies on hydrating topical treatment and avoidance of specific and unspecific provocation factors. Anti-inflammatory treatment based on topical glucocorticosteroids and topical calcineurin antagonists is used for exacerbation management and more recently for proactive therapy in selected cases. Topical corticosteroids remain the mainstay of therapy, but the topical calcineurin inhibitors, tacrolimus and pimecrolimus are preferred in certain locations. Systemic anti-inflammatory treatment is an option for severe refractory cases. Microbial colonization and superinfection may induce disease exacerbation and can justify additional antimicrobial/antiseptic treatment. Systemic antihistamines (H1) can relieve pruritus, but do not have sufficient effect on eczema. Adjuvant therapy includes UV irradiation preferably of UVA1 wavelength or UVB 311 nm. Dietary recommendations should be specific and given only in diagnosed individual food allergy. Allergen-specific immunotherapy to aeroallergens may be useful in selected cases. Stress-induced exacerbations may make psychosomatic counselling recommendable. 'Eczema school' educational programmes have been proven to be helpful.


Assuntos
Dermatite Atópica/diagnóstico , Dermatite Atópica/terapia , Dermatologia , Eczema/diagnóstico , Eczema/terapia , Publicações Periódicas como Assunto , Guias de Prática Clínica como Assunto/normas , Antibacterianos/uso terapêutico , Fármacos Dermatológicos/uso terapêutico , Diagnóstico Diferencial , Antagonistas dos Receptores Histamínicos/uso terapêutico , Humanos , Fototerapia/métodos
15.
J Intern Med ; 266(1): 69-83, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19522827

RESUMO

Several cancer-related genes have been discovered and molecular test for the cancer genetic risk assessment has been widely increasing. Disorders such as Multiple Endocrine Neoplasia syndromes have received benefits from the identification of the responsible genes whose mutations account for the genetic susceptibility to develop endocrine tumours. Primary hyperparathyroidism (PHPT)is a clinical phenotype frequently associated to Multiple Endocrine Neoplasia syndromes, but it can also represent the unique endocrinopathy recurring as a familial cluster. In recent years, care options have been made available to patients and families with hereditary PHPT, and the process of systematically assessing the genetic risk has been becoming increasingly important. This review aims to help health providers not frequently dealing with genetic testing use and it will introduce some general concepts concerning genetic diagnosis issues. As an example the role and the practical usefulness of DNA-based diagnosis in patients affected by different forms of congenital PHPT is described, with a close look on why, when and how genetic testing should be performed in these subjects and their relatives. Some practical recommendations and suggestions concerning on how to deal when a suspect or known case of familial PHPT has to be faced conclude this manuscript.


Assuntos
Testes Genéticos/métodos , Hiperparatireoidismo Primário/diagnóstico , DNA de Neoplasias/genética , Humanos , Hiperparatireoidismo Primário/genética , Neoplasia Endócrina Múltipla/diagnóstico , Neoplasia Endócrina Múltipla/genética , Mutação , Fenótipo
16.
Cell Death Differ ; 14(2): 338-47, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16794602

RESUMO

p66Shc, a redox enzyme that enhances reactive oxygen species (ROS) production by mitochondria, promotes T cell apoptosis. We have addressed the mechanisms regulating p66Shc-dependent apoptosis in T cells exposed to supraphysiological increases in [Ca2+]c. p66Shc expression resulted in profound mitochondrial dysfunction in response to the Ca2+ ionophore A23187, as revealed by dissipation of mitochondrial transmembrane potential, cytochrome c release and decreased ATP levels. p66Shc expression also caused a dramatic alteration in the cells' Ca2+-handling ability, which resulted in Ca2+ overload after A23187 treatment. The impairment in Ca2+ homeostasis was ROS dependent and caused by defective Ca2+ extrusion due at least in part to decreased plasma membrane ATPase (PMCA) expression. Both effects of p66Shc required Ca2+-dependent serine-36 phosphorylation. The mitochondrial effects of p66Shc were potentiated by but not strictly dependent on the rise in [Ca2+]c. Thus, Ca2+-dependent p66Shc phosphorylation causes both mitochondrial dysfunction and impaired Ca2+ homeostasis, which synergize in promoting T cell apoptosis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose , Cálcio/metabolismo , Homeostase , Mitocôndrias/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia , Apoptose/efeitos dos fármacos , Calcimicina/farmacologia , Regulação para Baixo/efeitos dos fármacos , Citometria de Fluxo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Humanos , Células Jurkat , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Fosfosserina/metabolismo , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Adaptadoras da Sinalização Shc , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src , Linfócitos T/efeitos dos fármacos , Linfócitos T/ultraestrutura
17.
Eur J Clin Nutr ; 62(11): 1351-4, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17657227

RESUMO

We investigated the association of melanoma risk with food consumption in a northern Italian population in which disease risk was shown to correlate with linoleic acid and soluble carbohydrates intake. We collected information regarding the habitual consumption of 188 food items in 59 patients with newly diagnosed cutaneous melanoma and 59 sex- and age-matched population controls. In the unadjusted analyses, the intake of several foodstuffs directly or inversely correlated with melanoma risk. In multivariate analysis adjusting for several potential confounders, risk correlated directly with vegetable oil intake and inversely with consumption of crispbreads and rusks. Overall, most of the food items rich in linoleic acid and soluble carbohydrates were unrelated to disease risk. Despite the limited statistical precision of the point estimates, these findings seem to indicate that consumption of specific foods may influence melanoma risk.


Assuntos
Dieta , Melanoma/epidemiologia , Neoplasias Cutâneas/epidemiologia , Estudos de Casos e Controles , Carboidratos da Dieta/administração & dosagem , Ácidos Graxos Insaturados/administração & dosagem , Feminino , Humanos , Itália/epidemiologia , Ácido Linoleico/administração & dosagem , Masculino , Melanoma/etiologia , Análise Multivariada , Razão de Chances , Óleos de Plantas/administração & dosagem , Fatores de Risco , Neoplasias Cutâneas/etiologia
18.
J Insect Physiol ; 101: 22-30, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28623149

RESUMO

Parasitic castration is an adaptive strategy where parasites usurp the hosts' reproductive physiology to complete their life cycle. The alterations in the host traits vary in their magnitude, from subtle changes in the host morpho-physiology and behaviour to the production of complex aberrant phenotypes, which often depend on the host gender. The strepsipteran macroparasite Xenos vesparum induces dramatic behavioural and physiological changes in its female host, the paper wasp Polistes dominula, while its effect on the male phenotype is largely unknown. In this study we investigated how a single X. vesparum parasite influences the functional morphology of P. dominula male reproductive apparatus. We performed morphometry and ultrastructure characterization of corpora allata, testes, seminal vesicles and accessory glands in parasitized and unparasitized males, and also in young and old males to control for the effect of age on the natural deterioration of these organs. Our results show that age significantly affects the development of male reproductive apparatus. A low parasite load - one parasite per host is the common prevalence in the field - has only a marginal impact on the reproductive morphology of P. dominula males, affecting quantitatively but not qualitatively the protein content of male accessory glands. Thus, in male P. dominula wasps, X. vesparum appears to behave as a true "parasite", in clear opposition to the role of "parasitoid" that it takes in female hosts where castration causes the reproductive death.


Assuntos
Corpora Allata/parasitologia , Interações Hospedeiro-Parasita , Insetos/fisiologia , Vespas/parasitologia , Animais , Corpora Allata/anatomia & histologia , Corpora Allata/ultraestrutura , Genitália Masculina/anatomia & histologia , Genitália Masculina/parasitologia , Genitália Masculina/ultraestrutura , Masculino , Microscopia Eletrônica de Transmissão
19.
Tissue Cell ; 38(3): 177-86, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16620898

RESUMO

The aberrant spermatogenesis of the haploid insect Haplothrips simplex (Thysanoptera) is described. The process, which occurs in the pupal instars, is characterized by two mitotic divisions, the second of which gives rise to two different-sized spermatids: the larger spermatids have a nucleus with diffuse chromatin and proceed into spermiogenesis, while the small spermatids have pycnotic nuclei and degenerate. Both types of spermatids contain two centrioles parallely rather than orthogonally oriented. The occurrence of two centrioles supports a close relationship between Thysanoptera and Phthyraptera. Before the beginning of spermiogenesis, however, the functional spermatids show the unusual presence of a third parallel centriole which is formed by the duplication of one of the two pre-existing centrioles.


Assuntos
Insetos/fisiologia , Insetos/ultraestrutura , Animais , Núcleo Celular/fisiologia , Núcleo Celular/ultraestrutura , Centríolos/fisiologia , Centríolos/ultraestrutura , Haploidia , Larva/metabolismo , Larva/ultraestrutura , Masculino , Espermátides/fisiologia , Espermátides/ultraestrutura , Espermatogênese/fisiologia
20.
Tissue Cell ; 38(6): 361-71, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17097701

RESUMO

Secondary metabolites of the neem tree (Azadirachta indica A. Juss., Meliaceae) exhibit a wide range of biological activities in insects. However, few studies have addressed the effects of neem extracts or compounds in arthropods of medical importance. In this study, a laboratory strain of Anopheles stephensi was used to assess the effects of a commercial formulation (Neem Azal) (NA)), containing azadirachtin A at 34%, on blood feeding, oviposition and oocyte ultrastructure. Oral administration of Neem Azal) to A. stephensi females through artificial blood meals did impair blood intake and oviposition in a concentration dependent manner. Similar results were obtained on females, which had consumed Neem Azal) in sucrose solution before taking a blood meal of plain blood. Neem treated females displayed a delay in oocyte development in both the phase of vitellogenesis and the phase of choriogenesis. The ultrastructural studies on ovaries from Neem Azal) treated females revealed distinct structural modifications indicative of: (i) a complete block of oogenesis, (ii) impairment of vitellogenesis and vitelline envelope formation, (iii) a severe degeneration of follicle cells. In agreement with results obtained in other insects, this study indicates that Neem Azal) impairs hormone control of oogenesis and exerts a cytotoxic effect on both follicular cells and oocytes of the Asian malaria vector A. stephensi.


Assuntos
Anopheles/efeitos dos fármacos , Azadirachta/química , Comportamento Alimentar/efeitos dos fármacos , Inseticidas/farmacologia , Limoninas/farmacologia , Oócitos/efeitos dos fármacos , Animais , Anopheles/fisiologia , Anopheles/ultraestrutura , Sangue , Feminino , Microscopia Eletrônica de Transmissão , Oócitos/ultraestrutura , Oviposição/efeitos dos fármacos , Extratos Vegetais/farmacologia , Vitelogênese/efeitos dos fármacos
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