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1.
Tissue Cell ; 76: 101806, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35561472

RESUMO

Most Majoidea crabs display high sperm competition rates due to the development of spermatic strata within the seminal receptacle (SR). To verify the occurrence of sperm competition, SR anatomy and histochemistry analyses were performed in Mithrax hispidus, Omalacantha bicornuta, and Mithraculus forceps. The SR of the three Mithracidae species is classified into two regions, one of mesodermal origin (dorsal), consisting of a stratified epithelium with desquamation cells that produce a holocrine secretion, and the other, an ectodermal region (ventral) comprising a simple cubic epithelium covered by a cuticle. The oviduct opens in a ventral position near the transition region, which exhibits more pronounced folds on the opposite face of the oviduct, which may aid fertilization due to the presence of an external musculature. Sperm masses in a circular format were observed in the SR lumen, reminiscent of coenospermic spermatophores, and no morphological evidence strata of sperm packets were observed in any of the three studied species. The ventral SR followed the most common pattern observed in Majoidea. The secretion produced in the receptacle is composed of glycoproteins, with neutral polysaccharides. Acidic polysaccharides probably play a role against microorganisms from male seminal fluid. Due to the absence sperm packets, we were unable to determine whether the investigated females receive material from more than one male nor (if this does, in fact, occur) whether any preference for the spermatozoa of one male over another takes place during fertilization, that can may indicate the absence of sperm competition in the investigated species.


Assuntos
Braquiúros , Animais , Epitélio , Tubas Uterinas , Feminino , Humanos , Masculino , Espermatogônias , Espermatozoides
2.
Tissue Cell ; 66: 101395, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32933718

RESUMO

The ovarian development of Callinectes ornatus and Arenaeus cribrarius was described using histochemistry and ultrastructure. Both species shows the same ovarian stages, which are the juvenile (JUV), adult rudimentary (RUD), developing (DEV), intermediary (INT), mature (MAT), and spent (OV) stages. The JUV and RUD stages showed similar characteristics, and previtellogenesis is characterized by meiotic prophase chromosomes. In the primary vitellogenesis, the oocyte cytoplasm shows many small and large cytoplasmic glycoprotein vesicles. These vesicles correspond to the dilated cisternae of the rough endoplasmic reticulum (RER), which produces the immature (endogenous) yolk. Secondary vitellogenesis (exogenous phase) begins at the DEV stage with the fusion of pinocytic vesicles and vesicles with immature yolks to form mature yolk granules. At the INT stage, the formation of the chorion begins, and the mature yolks increase in size and number, while the RER diminishes. In the MAT stage, the oocytes are completely formed, and the cytoplasm is filled with mature yolk, lipid droplets, and glycogen. There are no significant variations between the gonadosomatic and hepatosomatic indices, which allows us to infer that the transfer of reserves from the hepatopancreas is nearly constant during ovarian development, since we observed primiparous and multiparous females in the same sampled population.


Assuntos
Braquiúros/ultraestrutura , Ovário/ultraestrutura , Natação , Exoesqueleto/ultraestrutura , Animais , Feminino , Oócitos/citologia , Oócitos/ultraestrutura , Oogônios/citologia , Oogônios/ultraestrutura , Vitelogênese
3.
Gynecol Endocrinol ; 36(11): 1010-1014, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32401078

RESUMO

Endometriosis is a chronic inflammatory disease of women of reproductive age. Small bowel (SB) permeability and lipopolysaccharides (LPS) could play a role in the perduration of low grade inflammation status and the pathogenesis of endometriosis. To clarify this hypothesis, we measured SB permeability through plasma values of LPS and urinary secretion of lactulose (La), mannitol (Ma) and their ratio (L/M) in patients with endometriosis compared with healthy controls (HC). Eight patients and 14 HC entered the study. SB permeability was evaluated by high-performance liquid chromatography of urine concentrations of La and Ma. Plasma levels of LPS were measured in the blood. Moreover, a nutritional, gastroenterological, quality of life evaluation was performed through validates questionnaires and complete gynaecological evaluations. The statistical analysis of the obtained data did not show differences in anthropometric and nutritional characteristics and gastrointestinal functional disease in the two groups. Patients reported higher levels of pelvic chronic pain (3.87 ± 2.99 vs 0.15 ± 0.55; pe = 0.001) and significantly higher LPS plasma levels (0.529 ± 0.11 vs 0.427 ± 0.08; p value = .027) than HC. Our results indicate that intestinal permeability is abnormal in endometriosis patients, and it might play a role in the pathogenesis of this chronic disease.


Assuntos
Endometriose/metabolismo , Gastroenteropatias/metabolismo , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Adulto , Estudos de Casos e Controles , Endometriose/complicações , Endometriose/urina , Feminino , Gastroenteropatias/complicações , Gastroenteropatias/urina , Humanos , Itália , Lactulose/farmacocinética , Lactulose/urina , Lipopolissacarídeos/sangue , Manitol/farmacocinética , Manitol/urina , Permeabilidade , Projetos Piloto , Qualidade de Vida , Adulto Jovem
4.
Environ Sci Pollut Res Int ; 21(10): 6516-24, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24488552

RESUMO

Butyltin (BT) contamination was evaluated in hermit crabs from 25 estuaries and in sediments from 13 of these estuaries along about 2,000 km of the Brazilian coast. BT contamination in hermit crabs ranged from 2.22 to 1,746 ng Sn g(-1) of DBT and 1.32 to 318 ng Sn g(-1) of TBT. In sediment samples, the concentration also varied widely, from 25 to 1,304 ng Sn g(-1) of MBT, from 7 to 158 ng Sn g(-1) of DBT, and from 8 to 565 ng Sn g(-1) of TBT. BTs are still being found in surface sediments and biota of the estuaries after the international and Brazilian bans, showing heterogeneous distribution among and within estuaries. Although hermit crabs were previously tested as an indicator of recent BT contamination, the results indicate the presence of contamination, probably from resuspension of BTs from deeper water of the estuary.


Assuntos
Anomuros/química , Desinfetantes/análise , Monitoramento Ambiental , Estuários , Sedimentos Geológicos/química , Compostos Orgânicos de Estanho/análise , Poluentes Químicos da Água/análise , Animais , Brasil , Pintura/análise
6.
Biochem Biophys Res Commun ; 439(3): 369-72, 2013 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-23998934

RESUMO

Hypomyelination and congenital cataract (HCC, OMIM #610532) is a rare autosomal recessive disorder due to FAM126A mutations characterized by congenital cataract, progressive neurologic impairment, and myelin deficiency in the central and peripheral nervous system. We have identified two novel mutations in three affected members of two unrelated families. Two sibs harbouring a microdeletion causing a premature stop in the protein showed the classical clinical and neuroradiologic HCC picture. The third patient carrying a missense mutation showed a relatively mild clinical picture without peripheral neuropathy. A residual amount of hyccin protein in primary fibroblasts was demonstrated by functional studies indicating that missense mutations are likely to have less detrimental effects if compared with splice-site mutations or deletions that cause the full-blown HCC phenotype, including peripheral nervous system involvement.


Assuntos
Catarata/congênito , Catarata/genética , Doença de Charcot-Marie-Tooth/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Mutação , Sequência de Aminoácidos , Encéfalo/metabolismo , Encéfalo/patologia , Catarata/patologia , Doença de Charcot-Marie-Tooth/patologia , Criança , Feminino , Humanos , Lactente , Peptídeos e Proteínas de Sinalização Intracelular/química , Proteínas de Membrana/química , Dados de Sequência Molecular , Linhagem , Alinhamento de Sequência
8.
Eur J Neurol ; 20(5): 856-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23020086

RESUMO

BACKGROUND AND PURPOSES: To determine the prevalence of SLC2A1 mutations in children with early-onset absence epilepsy (EOAE) and to investigate whether there were differences in demographic and electroclinical data between patients who became seizure-free with anti-epileptic drug (AED) monotherapy (group I) and those who needed add-on treatment of a second AED (group II). METHODS: We reviewed children with EOAE attending different Italian epilepsy centers. All participants had onset of absence seizures within the first 3 years of life but otherwise conformed to a strict definition of childhood absence epilepsy. Mutation analysis of SLC2A1 was performed in each patient. RESULTS: Eighty-four children (57 in group I, 27 in group II) fulfilled the inclusion criteria. No mutation in SLC2A1 was found. There were no statistical differences between the two groups with regard to F/M ratio, age at onset of EOAE, early history of febrile seizures, first-degree family history for genetic generalized epilepsy, duration of AED therapy at 3 years after enrollment, use of AEDs at 3 years, failed withdrawals at 3 years, terminal remission of EOAE at 3 years, and 6-month follow-up EEG data. Mean duration of seizures/active epilepsy was significantly shorter in group I than in group II (P = 0.008). CONCLUSIONS: We demonstrate that in a large series of children with rigorous diagnosis of EOAE, no mutations in SLC2A1 gene are detected. Except for duration of seizures/active epilepsy, no significant differences in demographic and electroclinical aspects are observed between children with EOAE who responded well to AED monotherapy and those who became seizure-free with add-on treatment of a second AED.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsia Tipo Ausência/genética , Transportador de Glucose Tipo 1/genética , Mutação/genética , Anticonvulsivantes/administração & dosagem , Pré-Escolar , Quimioterapia Combinada , Epilepsia Tipo Ausência/tratamento farmacológico , Feminino , Humanos , Masculino , Estudos Retrospectivos
9.
Neurology ; 78(8): 557-62, 2012 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-22282645

RESUMO

OBJECTIVE: The idiopathic generalized epilepsies (IGE) are the most common genetically determined epilepsies. However, the underlying genes are largely unknown. We screened the SLC2A1 gene, encoding the glucose transporter type 1 (GLUT1), for mutations in a group of 95 European patients with familial IGE. METHODS: The affected individuals were examined clinically by EEG and brain imaging. The coding regions of SLC2A1 were sequenced in the index cases of all families. Wild-type and mutant transporters were expressed and functionally characterized in Xenopus laevis oocytes. RESULTS: We detected a novel nonsynonymous SLC2A1 mutation (c.694C>T, p.R232C) in one IGE family. Nine family members were affected mainly by absence epilepsies with a variable age at onset, from early childhood to adulthood. Childhood absence epilepsy in one individual evolved into juvenile myoclonic epilepsy. Eight affected and 4 unaffected individuals carried the mutation, revealing a reduced penetrance of 67%. The detected mutation was not found in 846 normal control subjects. Functional analysis revealed a reduced maximum uptake velocity for glucose, whereas the affinity to glucose and the protein expression were not different in wild-type and mutant transporters. CONCLUSION: Our study shows that GLUT1 defects are a rare cause of classic IGE. SLC2A1 screening should be considered in IGE featuring absence epilepsies with onset from early childhood to adult life, because this diagnosis may have important implications for treatment and genetic counseling.


Assuntos
Epilepsia Generalizada/genética , Transportador de Glucose Tipo 1/genética , Mutação , Alelos , Criança , Pré-Escolar , Feminino , Genótipo , Humanos , Masculino , Neuroimagem , Linhagem , Fenótipo , Adulto Jovem
10.
Minerva Pediatr ; 63(3): 217-25, 2011 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-21654601

RESUMO

During the last two decades, the molecular revolution in medicine has had a strong impact in the field of epilepsies. The quest for epilepsy-genes has been focused mainly on large mendelian pedigrees. This approach has allowed the identification of new causative genes and has provided new information about the pathogenesis of many epilepsy syndromes. Neverthless, the clinical implication of this information still has a relatively little impact on the genetic counselling for most of the syndromes.


Assuntos
Epilepsia/genética , Criança , Medicina Baseada em Evidências , Estudos de Associação Genética , Humanos
12.
Neurology ; 75(16): 1459-64, 2010 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-20956791

RESUMO

BACKGROUND: Mutations in genes encoding subunits of the tRNA-splicing endonuclease (TSEN) complex were identified in patients with pontocerebellar hypoplasia 2 (PCH2) and pontocerebellar hypoplasia 4 (PCH4). OBJECTIVE: We report molecular genetic findings in 12 Italian patients with clinical and MRI findings compatible with PCH2 and PCH4. METHODS: We retrospectively selected a cohort of 12 children from 9 Italian families with MRI of hypoplastic pontocerebellar structures and clinical manifestations suggesting either PCH2 or PCH4 and submitted them to direct sequencing of the genes encoding the 4 subunits of the TSEN complex, namely TSEN54, TSEN34, TSEN15, and TSEN2. RESULTS: In a cohort of 12 children, we detected the common p.A307S mutation in TSEN54 in 9/12 available patients from nine unrelated families. We also detected a novel c.1170_1183del (p. V390fs39X) in compound heterozygosity with the common p.A307S in a child with a severe PCH4 phenotype. In another severely affected patient, the second mutant allele was not identified. Two sibs without mutations in the TSEN complex were unlinked to the PCH3 locus. In addition to typical clinical and neuroradiologic features of PCH2, both children were affected by a tubulopathy resembling Bartter syndrome. CONCLUSIONS: We confirm that the common p.A307S mutation in TSEN54 is responsible for most of the patients with a PCH2 phenotype. The presence of a heterozygous in/del variant correlates with a more severe phenotype as PCH4. In addition, we describe a new clinical form of PCH in 2 sibs with clinical and MRI features of PCH2.


Assuntos
Encefalopatias/genética , Encefalopatias/patologia , Cerebelo/patologia , Endorribonucleases/genética , Ponte/patologia , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Endorribonucleases/classificação , Saúde da Família , Feminino , Humanos , Lactente , Recém-Nascido , Itália , Imageamento por Ressonância Magnética/métodos , Masculino , Mutação , Estudos Retrospectivos
13.
Micron ; 41(3): 183-6, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20022511

RESUMO

The location and ultrastructure of bacteria associated with microvilli in the midgut of Odontomachus bauri were examined by transmission electron microscopy. These filamentous type bacteria are the second morphotype described in the midgut of this ant. They colonizes only the ectoperitrophic space, more specifically attaching along microvilli. A thick capsule attaches bacteria to microvilli and protect them from acidic pH and digestive enzymes. Details of the location and association with microvilli are discussed.


Assuntos
Formigas/microbiologia , Bactérias/isolamento & purificação , Animais , Bactérias/ultraestrutura , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/ultraestrutura , Mucosa Intestinal/microbiologia , Mucosa Intestinal/ultraestrutura , Microscopia Eletrônica de Transmissão
14.
Artigo em Inglês | MEDLINE | ID: mdl-19964669

RESUMO

Our main work consists in modeling of the female pelvis and uterus, as well as the human fetus. The goal of this work is to recover the different forces generated during the delivery. These forces will be input to the haptic obstetric training tool BirthSim which has already been developed by the Ampère Laboratory at the INSA of Lyon. This modeling process will permit us to develop a new training device to take into account different anatomies and different types of delivery. In this paper, we will firstly show the different existing haptic and virtual simulators in the obstetric world with their advantages and drawbacks. After, we will present our approach based on a biomechanical modeling of concerned organs. To obtain interactive time performance, we proceed by the simplification of the organs anatomy. Then, we present some results showing that FEM analysis can be used to model forces during childbirth. In the future, we plan to use this work to more accurately control a childbirth simulator.


Assuntos
Simulação por Computador , Feto/fisiologia , Genitália Feminina/fisiologia , Modelos Biológicos , Parto/fisiologia , Fenômenos Biomecânicos , Feminino , Humanos , Gravidez , Contração Uterina/fisiologia
15.
Micron ; 40(2): 194-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18980845

RESUMO

We conducted ultrastructural studies to examine the presence of microorganisms in the midgut of the ant Odontomachus bauri (Ponerinae), as a contribution towards understanding the relationships between microorganisms and their hosts. The presence of microorganisms in this region, including inside the cells, suggests their participation in food digestion as symbiontic organisms and represent a new possibility to exploit food sources in the environment.


Assuntos
Formigas/microbiologia , Trato Gastrointestinal/microbiologia , Simbiose , Animais , Formigas/anatomia & histologia , Formigas/ultraestrutura , Trato Gastrointestinal/ultraestrutura , Microscopia Eletrônica de Transmissão
16.
PLoS One ; 3(7): e2567, 2008 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-18596979

RESUMO

This work centres on the genomic comparisons of two closely-related nitrogen-fixing symbiotic bacteria, Rhizobium leguminosarum biovar viciae 3841 and Rhizobium etli CFN42. These strains maintain a stable genomic core that is also common to other rhizobia species plus a very variable and significant accessory component. The chromosomes are highly syntenic, whereas plasmids are related by fewer syntenic blocks and have mosaic structures. The pairs of plasmids p42f-pRL12, p42e-pRL11 and p42b-pRL9 as well large parts of p42c with pRL10 are shown to be similar, whereas the symbiotic plasmids (p42d and pRL10) are structurally unrelated and seem to follow distinct evolutionary paths. Even though purifying selection is acting on the whole genome, the accessory component is evolving more rapidly. This component is constituted largely for proteins for transport of diverse metabolites and elements of external origin. The present analysis allows us to conclude that a heterogeneous and quickly diversifying group of plasmids co-exists in a common genomic framework.


Assuntos
Genoma Bacteriano , Fixação de Nitrogênio/genética , Plasmídeos/genética , Rhizobium etli/genética , Rhizobium leguminosarum/genética , Simbiose/genética , Evolução Molecular , Modelos Genéticos , Filogenia , Plasmídeos/metabolismo , Sintenia
17.
Micron ; 39(8): 1179-83, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18579390

RESUMO

Given the physiological importance of the Malpighian tubules to homeostasis in ants, this study aimed to characterize the enzymology, histology, histochemistry, and ultramorphology of the Malpighian tubules of Cephalotes atratus, C. clypeatus, and C. pusillus, as a contribution for the understanding of this organ, as well as to examine its role in the maintenance of symbiontic microorganisms in the ileum of these ants.


Assuntos
Formigas/microbiologia , Túbulos de Malpighi/microbiologia , Simbiose , Adenosina Trifosfatases/análise , Animais , Concentração de Íons de Hidrogênio , Túbulos de Malpighi/enzimologia , Túbulos de Malpighi/ultraestrutura
19.
Clin Genet ; 74(1): 54-60, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18341608

RESUMO

The acronym IBMPFD denotes a syndrome including inclusion body myopathy, Paget's disease of the bone (PDB) and frontotemporal dementia (FTD) as cardinal features, which is caused by missense mutations in the VCP gene. We studied the clinical characteristics and the histopathological features in two siblings and their mother who presented with adult-onset myopathy and presenile, rapidly progressive FTD. One sibling also showed PDB. Light and electron microscopy performed on muscle biopsies demonstrated degenerative changes with inclusion bodies and abnormal aggregates. Mutation analysis of the VCP gene on affected siblings revealed a heterozygous missense mutation (R155H) in a hot spot. This is the first Italian family with multiple individuals diagnosed as having IBMPFD and carrying the recurrent R155H mutation. The implications for genetic counselling were also discussed, with regard to the procedures that may be offered to families suffering from a multisystem disorder with high risk of cognitive decline.


Assuntos
Adenosina Trifosfatases/genética , Proteínas de Ciclo Celular/genética , Demência/genética , Miosite de Corpos de Inclusão/genética , Osteíte Deformante/genética , Adulto , Análise Mutacional de DNA , Feminino , Aconselhamento Genético , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Linhagem , Síndrome , Proteína com Valosina
20.
AJNR Am J Neuroradiol ; 29(2): 301-5, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17974614

RESUMO

BACKGROUND AND PURPOSE: Hypomyelination and congenital cataract (HCC) is an autosomal recessive white matter disease caused by deficiency of hyccin, a membrane protein implicated in both central and peripheral myelination. We aimed to describe the neuroimaging features of this novel entity. MATERIALS AND METHODS: A systematic analysis of patients with unclassified leukoencephalopathies admitted to our institutions revealed 10 children with congenital cataract, slowly progressive neurologic impairment, and diffuse white matter abnormalities on neuroimaging. Psychomotor developmental delay was evident after the first year of life. Peripheral neuropathy was demonstrated by neurophysiologic studies in 9 children. The available neuroimaging studies were retrospectively reviewed. RESULTS: In all patients, neuroimaging revealed diffuse involvement of the supratentorial white matter associated with preservation of both cortical and deep gray matter structures. Supratentorial white matter hypomyelination was detected in all patients; 7 patients also had evidence of variably extensive areas of increased white matter water content. Deep cerebellar white matter hypomyelination was found in 6 patients. Older patients had evidence of white matter bulk loss and gliosis. Proton MR spectroscopy showed variable findings, depending on the stage of the disease. Sural nerve biopsy revealed hypomyelinated nerve fibers. Mutations in the DRCTNNB1A gene on chromosome 7p15.3, causing complete or severe deficiency of hyccin, were demonstrated in all patients. CONCLUSIONS: HCC is characterized by a combined pattern of primary myelin deficiency and secondary neurodegenerative changes. In the proper clinical setting, recognition of suggestive neuroimaging findings should prompt appropriate genetic investigations.


Assuntos
Encéfalo/patologia , Catarata/congênito , Catarata/diagnóstico , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/congênito , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central/diagnóstico , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Fibras Nervosas Mielinizadas/patologia , Estudos Retrospectivos , Síndrome
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