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2.
Acta Diabetol ; 59(8): 1073-1082, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35641837

RESUMO

AIMS: We present an innovative method based on haptics for the evaluation of the sense of touch in the hand, in people affected by type 1 diabetes. METHODS: Forty individuals affected by diabetes and 20 healthy controls took part in the study; the diabetes group was further divided into two subgroups based on vibration sensitivity in the lower limb. By means of a novel haptic device, tactile sensitivity in the fingertip was measured as the ability of the participants to discriminate slip motion speed. RESULTS: Tactile sensitivity was significantly lower in individuals affected by diabetes as compared to controls. Depending on the subgroup, the difference from the controls was equal to 0.11 (95% CI from 0.029 to 0.186) and to 0.267 (95% CI from 0.198 to 0.336). Within the diabetes group, tactile sensitivity correlated with vibration sensitivity in the upper (p = 0.001) and lower limb (p = 0.003). A significant relationship between nerve conduction parameters and tactile sensitivity was found (p = 0.03). Finally, we combined the different predictors (clinical, vibratory and electroneurography data) by using cluster analysis; tactile sensitivity was found to be significantly different between different clusters (p = 0.004). CONCLUSIONS: Early signs of tactile dysfunction in the hand were found in individuals affected by diabetes, even in absence of diabetic neuropathy. The protocol presented in this study is a promising tool for the assessment of tactile dysfunction in the hand in people affected by type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1 , Percepção do Tato , Diabetes Mellitus Tipo 1/complicações , Tecnologia Háptica , Humanos , Tato/fisiologia , Percepção do Tato/fisiologia , Vibração
3.
Sci Adv ; 5(6): eaaw3121, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31183406

RESUMO

Recent studies extended the classical view that touch is mainly devoted to the perception of the external world. Perceptual tasks where the hand was stationary demonstrated that cutaneous stimuli from contact with objects provide the illusion of hand displacement. Here, we tested the hypothesis that touch provides auxiliary proprioceptive feedback for guiding actions. We used a well-established perceptual phenomenon to dissociate the estimates of reaching direction from touch and musculoskeletal proprioception. Participants slid their fingertip on a ridged plate to move toward a target without any visual feedback on hand location. Tactile motion estimates were biased by ridge orientation, inducing a systematic deviation in hand trajectories in accordance with our hypothesis. Results are in agreement with an ideal observer model, where motion estimates from different somatosensory cues are optimally integrated for the control of movement. These outcomes shed new light on the interplay between proprioception and touch in active tasks.


Assuntos
Movimento , Propriocepção/fisiologia , Tato/fisiologia , Adulto , Sinais (Psicologia) , Feminino , Mãos/fisiologia , Humanos , Masculino , Estimulação Luminosa , Percepção Visual , Adulto Jovem
4.
J Wound Care ; 25(6): 305-17, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27286663

RESUMO

The potential impact of biofilm on healing in acute and chronic wounds is one of the most controversial current issues in wound care. A significant amount of laboratory-based research has been carried out on this topic, however, in 2013 the European Wound Management Association (EWMA) pointed out the lack of guidance for managing biofilms in clinical practice and solicited the need for guidelines and further clinical research. In response to this challenge, the Italian Nursing Wound Healing Society (AISLeC) initiated a project which aimed to achieve consensus among a multidisciplinary and multiprofessional international panel of experts to identify what could be considered part of 'good clinical practice' with respect to the recognition and management of biofilms in acute and chronic wounds. The group followed a systematic approach, developed by the GRADE working group, to define relevant questions and clinical recommendations raised in clinical practice. An independent librarian retrieved and screened approximately 2000 pertinent published papers to produce tables of levels of evidence. After a smaller focus group had a multistep structured discussion, and a formal voting process had been completed, ten therapeutic interventions were identified as being strongly recommendable for clinical practice, while another four recommendations were graded as being 'weak'. The panel subsequently formulated a preliminary statement (although with a weak grade of agreement): 'provided that other causes that prevent optimal wound healing have been ruled out, chronic wounds are chronically infected'. All members of the panel agreed that there is a paucity of reliable, well-conducted clinical trials which have produced clear evidence related to the effects of biofilm presence. In the meantime it was agreed that expert-based guidelines were needed to be developed for the recognition and management of biofilms in wounds and for the best design of future clinical trials. This is a fundamental and urgent task for both laboratory-based scientists and clinicians.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Bandagens , Biofilmes , Queimaduras/terapia , Desbridamento/métodos , Pé Diabético/terapia , Úlcera por Pressão/terapia , Deiscência da Ferida Operatória/terapia , Úlcera Varicosa/terapia , Infecção dos Ferimentos/terapia , Anti-Infecciosos/uso terapêutico , Queimaduras/diagnóstico , Pé Diabético/diagnóstico , Gerenciamento Clínico , Humanos , Úlcera por Pressão/diagnóstico , Deiscência da Ferida Operatória/diagnóstico , Infecção da Ferida Cirúrgica/diagnóstico , Infecção da Ferida Cirúrgica/terapia , Úlcera Varicosa/diagnóstico , Infecção dos Ferimentos/diagnóstico , Ferimentos e Lesões/terapia
5.
J Wound Care ; 25(3): 160, 162-6, 168, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26947697

RESUMO

OBJECTIVE: Research into surfactant solutions for the debridement of chronic wounds suggests that surfactants may support wound bed preparation (WBP) in chronic wounds, however their efficacy has not been evaluated in randomised controlled trials (RCTs). Our aim was to assess the clinical efficacy of a propylbetaine-polihexanide (PP) solution versus normal saline (NS) solution in WBP, assessing inflammatory signs and wound size reduction in patients with pressure ulcers (PUs) or vascular leg ulcers. METHOD: In a single-blinded randomised controlled trial (RCT) patients were randomly allocated to two groups and treated with either propylbetaine-polihexanide (PP) solution (Prontosan) or NS. Wounds were assessed using the Bates-Jensen wound assessment tool (BWAT). Assessments took place at inclusion (T0), day 7 (T1), day 14 (T2), day 21 (T3), and day 28 (T4). Outcomes were analysed using a two-tailed Student's t-test. RESULTS: A total of 289 patients were included. Both groups had similar demographics, clinical status, and wound characteristics. Data analysis showed statistically significant differences between T0 and T4 for the following outcomes: BWAT total score, p=0.0248; BWAT score for inflammatory items, p=0.03; BWAT scores for wound size reduction (p=0.049) and granulation tissue improvement (p=0.043), all in favour of PP. The assessment of pain did not show any significant difference between the two groups. CONCLUSION: The study results showed significantly higher efficacy of the PP solution versus NS solution, in reducing inflammatory signs and accelerating the healing of vascular leg ulcers and PUs. This evidence supports the update of protocols for the care of chronic wounds. DECLARATION OF INTEREST: The authors have no conflict of interest regarding this research. This is an investigator initiated trial. B. Braun Milano SpA kindly provided the material under investigation for both treatment groups, and paid the Ethics Committees' application fees in all participating centres.


Assuntos
Bandagens , Betaína/uso terapêutico , Biguanidas/uso terapêutico , Úlcera por Pressão/terapia , Soluções/uso terapêutico , Irrigação Terapêutica/métodos , Úlcera Varicosa/terapia , Ferimentos e Lesões/terapia , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Feminino , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade , Úlcera por Pressão/imunologia , Método Simples-Cego , Cloreto de Sódio/uso terapêutico , Úlcera Varicosa/imunologia , Ferimentos e Lesões/imunologia
6.
J Perinatol ; 32(12): 981-4, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23190939

RESUMO

Major malformations, surgery and persistent pulmonary hypertension (PHT) have been considered contraindications to therapeutic hypothermia (TH) in newborns with hypoxic-ischemic encephalopathy (HIE). We report two patients with undiagnosed congenital diaphragmatic hernia (CDH) who developed HIE after birth. Diagnosis of moderate HIE was formulated based on clinical, laboratory and electroencephalographic criteria. The patients were treated with whole body hypothermia (33.5 °C) for 72 h. During hypothermia the patients underwent surgical repair with regular perioperative course. Ventilatory support with high-frequency oscillatory ventilation, oxygen requirements and inotropic support remained stable during hypothermia. Serial echocardiographic evaluations did not demonstrate any change in pulmonary pressure values. In our experience TH did not increase the risk of hemodynamic instability, PHT or bleeding. Hypothermia may be considered in patients with HIE and CDH or other surgical conditions with favorable prognosis.


Assuntos
Hérnias Diafragmáticas Congênitas , Herniorrafia/métodos , Hipotermia Induzida/métodos , Hipóxia-Isquemia Encefálica/cirurgia , Feminino , Seguimentos , Hemodinâmica/fisiologia , Hérnia Diafragmática/complicações , Hérnia Diafragmática/diagnóstico por imagem , Hérnia Diafragmática/cirurgia , Humanos , Hipóxia-Isquemia Encefálica/complicações , Hipóxia-Isquemia Encefálica/diagnóstico , Recém-Nascido , Gravidez , Testes de Função Respiratória , Medição de Risco , Estudos de Amostragem , Resultado do Tratamento , Ultrassonografia
7.
Plant Biol (Stuttg) ; 14(5): 770-82, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22288466

RESUMO

Pollen tube growth depends on the integrity of the actin cytoskeleton that regulates cytoplasmic streaming and secretion. To clarify whether actin also plays a role in pollen tube endocytosis, Latrunculin B (LatB) was employed in internalisation experiments with tobacco pollen tubes, using the lipophilic dye FM4-64 and charged nanogold. Time-lapse analysis and dissection of endocytosis allowed us to identify internalisation pathways with different sensitivity to LatB. Co-localisation experiments and ultrastructural observations using positively charged nanogold revealed that LatB significantly inhibited endocytosis in the pollen tube shank, affecting internalisation of the plasma membrane (PM) recycled for secretion, as well as that conveyed to vacuoles. In contrast, endocytosis of negatively charged nanogold in the tip, which is also conveyed to vacuoles, was not influenced. Experiments of fluorescence recovery after photobleaching (FRAP) of the apical and subapical PM revealed domains with different rates of fluorescence recovery and showed that these differences depend on the actin cytoskeleton integrity. These results show the presence of distinct degradation pathways by demonstrating that actin-dependent and actin-indepedent endocytosis both operate in pollen tubes, internalising tracts of PM to be recycled and broken down. Intriguingly, although most studies concentrate on exocytosis and distension in the apex, the present paper shows that uncharacterised, actin-dependent secretory activity occurs in the shank of pollen tubes.


Assuntos
Actinas/metabolismo , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Endocitose/efeitos dos fármacos , Exocitose/efeitos dos fármacos , Nicotiana/citologia , Tubo Polínico/citologia , Polimerização , Tiazolidinas/farmacologia , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Clatrina/metabolismo , Recuperação de Fluorescência Após Fotodegradação , Complexo de Golgi/efeitos dos fármacos , Complexo de Golgi/metabolismo , Complexo de Golgi/ultraestrutura , Tubo Polínico/efeitos dos fármacos , Tubo Polínico/crescimento & desenvolvimento , Tubo Polínico/ultraestrutura , Imagem com Lapso de Tempo , Vacúolos/efeitos dos fármacos , Vacúolos/ultraestrutura
8.
Neurocase ; 17(1): 46-56, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20981620

RESUMO

A deficit of declarative memory is a common sequela after a hypoxic episode. While the role of gray matter changes (i.e., atrophy of hippocampal formation) as mainly responsible for memory loss has been emphasized, the role of the white matter damage has so far been neglected. The present study was aimed at evaluating whether white matter damage, within the neural circuitry responsible for declarative memory functioning, is present in anoxic patients. We assessed, by means of voxel-based morphometry, the integrity of white matter regions in five patients with hypoxic amnesia. When anoxic patients were compared to healthy controls, significantly less white matter density was detected in the fornix, anterior portion of the cingulum bundle and uncinate fasciculus bilaterally. We conclude that cerebral hypoxia may alter, together with the hippocampi, the integrity of white matter fibers throughout the memory-limbic system.


Assuntos
Amnésia/patologia , Encéfalo/patologia , Fibras Nervosas Mielinizadas/patologia , Adulto , Amnésia/etiologia , Função Executiva , Humanos , Hipóxia/complicações , Processamento de Imagem Assistida por Computador/métodos , Inteligência , Imageamento por Ressonância Magnética/métodos , Masculino , Memória/fisiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos
9.
Minerva Pediatr ; 62(2): 147-51, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20440234

RESUMO

AIM: The aim of this study was to determine the role of parents after extubation of their children affected by Spinal Muscular Atrophy Type 1 (SMA1) in the Pediatric Intensive Care Unit. Currently, children affected by SMA1 are often treated with non-invasive mechanical ventilation and mechanical support of cough. During the first two or three years of life they frequently present severe respiratory failure requiring intubation. Extubation may be at severe risk of failure even because of inadequate care. METHODS: Parents of SMA1 children were offered an early education on the most critical aspects and a training in non-invasive respiratory support after diagnosis. They were asked and allowed to stay as longer as possible with their child after extubation. Quality and quantity of care given by parents during the first 24 hours after extubation were recorded. RESULTS: All parents participated to the success of the weaning procedure: they gave continuous care and all children could be extubated. CONCLUSION: The presence of parents after extubation of SMA1 patients is important for the success of the procedure; otherwise, the presence of a skilled nurse is needed, with a nurse-patient ratio of 1:1.


Assuntos
Pais , Atrofias Musculares Espinais da Infância/terapia , Desmame do Respirador , Feminino , Humanos , Lactente , Unidades de Terapia Intensiva , Masculino
10.
Br J Anaesth ; 97(5): 701-3, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17003066

RESUMO

Fibrodysplasia Ossificans Progressiva (FOP) is a rare inherited disease in which progressive ossification of striated muscles leads to severe disability and respiratory impairment early in life and there are associated characteristic congenital skeletal malformations. Although this condition may prove demanding for the anaesthetist, few reports are available regarding anaesthesia in paediatric patients. We review the clinical features of the disease relevant to anaesthesia and describe the perioperative care of an 18-month-old boy with FOP who underwent endoscopic third-ventriculostomy for hydrocephalus associated with a brainstem mass. We emphasize the importance of an appropriate anaesthetic management of these patients, as inadequate care may lead to exacerbation of the disease with permanent sequelae.


Assuntos
Anestesia Geral/métodos , Miosite Ossificante/complicações , Humanos , Hidrocefalia/cirurgia , Lactente , Masculino , Assistência Perioperatória/métodos , Ventriculostomia/métodos
12.
Mar Environ Res ; 54(3-5): 667-71, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12408633

RESUMO

The hypothesis that Mediterranean top predator species, such as large pelagic fish, are potentially at risk due to endocrine disrupting chemicals (EDCs), is investigated. The potential estrogenic effects of PHAHs in three fish species of commercial interest, the top predators bluefin tuna (Thunnus thynnus thynnus), swordfish (Xiphias gladius), and Mediterranean spearfish (Tetrapturus belone), were investigated using vitellogenin (Vtg), zona radiata proteins (Zrp) and mixed function oxidases (EROD, BPMO) as diagnostic tools. High induction of Vtg and Zrp was detected by western blot and ELISA techniques in adult males of X. gladius and T. thynnus thynnus, suggesting that these species are at high toxicological risk in the Mediterranean sea. Comparison of BPMO and EROD activities in the three species indicated, both in male and female, much higher MFO activity in bluefin tuna. This data suggests high exposure of this species to lipophilic xenobiotic contaminants in the Mediterranean environment.


Assuntos
Biomarcadores/análise , Sistema Endócrino/efeitos dos fármacos , Oxigenases de Função Mista/farmacologia , Perciformes/fisiologia , Vitelogeninas/biossíntese , Xenobióticos/efeitos adversos , Animais , Proteínas do Ovo/análise , Proteínas do Ovo/biossíntese , Exposição Ambiental , Feminino , Masculino , Oxigenases de Função Mista/análise , Vitelogeninas/análise , Poluentes Químicos da Água/efeitos adversos
13.
Mar Environ Res ; 52(5): 477-83, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11763150

RESUMO

Endocrine Disrupting Chemicals (EDCs) have the potential to alter hormone pathways that regulate reproductive processes in wildlife and fishes. In this research the hypothesis that Mediterranean top predator species (such as large pelagic fish) are potentially at risk due to EDCs is investigated. These marine organisms tend to accumulate high concentrations of EDCs such as polyhalogenated aromatic hydrocarbons (PHAHs). The potential effects of EDCs on a fish species of commercial interest, the top predator Xiphias gladius (swordfish), were investigated using vitellogenin (Vtg) and Zona radiata proteins (Zrp) as diagnostic and prognostic biomarkers. Dramatic induction of typically female proteins (Vtg and Zrp) was detected by ELISA and Western Blot in adult males of the species. These results are the first warning of the potential risk for reproductive function of Mediterranean top predators, and suggest the need for continuous monitoring of this fragile marine environment.


Assuntos
Proteínas do Ovo/análise , Peixes/metabolismo , Vitelogeninas/análise , Poluentes Químicos da Água/análise , Animais , Western Blotting , Sistema Endócrino/efeitos dos fármacos , Monitoramento Ambiental , Ensaio de Imunoadsorção Enzimática , Feminino , Masculino , Mar Mediterrâneo
14.
Plant Cell ; 12(9): 1719-36, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11006343

RESUMO

Pollen tube growth depends on the differential distribution of organelles and vesicles along the tube. The role of microtubules in organelle movement is uncertain, mainly because information at the molecular level is limited. In an effort to understand the molecular basis of microtubule-based movement, we isolated from tobacco pollen tubes polypeptides that cosediment with microtubules in an ATP-dependent manner. Major polypeptides released from microtubules by ATP (ATP-MAPs) had molecular masses of 90, 80, and 41 kD. Several findings indicate that the 90-kD ATP-MAP is a kinesin-related motor: binding of the polypeptide to microtubules was enhanced by the nonhydrolyzable ATP analog AMP-PNP; the 90-kD polypeptide reacted specifically with a peptide antibody directed against a highly conserved region in the motor domain of the kinesin superfamily; purified 90-kD ATP-MAP induced microtubules to glide in motility assays in vitro; and the 90-kD ATP-MAP cofractionated with microtubule-activated ATPase activity. Immunolocalization studies indicated that the 90-kD ATP-MAP binds to organelles associated with microtubules in the cortical region of the pollen tube. These findings suggest that the 90-kD ATP-MAP is a kinesin-related microtubule motor that moves organelles in the cortex of growing pollen tubes.


Assuntos
Microtúbulos/fisiologia , Nicotiana/fisiologia , Organelas/metabolismo , Plantas Tóxicas , Pólen/crescimento & desenvolvimento , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/farmacologia , Transporte Biológico/efeitos dos fármacos , Fracionamento Químico , Immunoblotting , Cinesinas/análise , Microscopia de Fluorescência , Peptídeos/metabolismo , Proteínas de Plantas/metabolismo , Pólen/ultraestrutura , Ligação Proteica , Nicotiana/citologia
15.
Int Rev Cytol ; 176: 133-99, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9394919

RESUMO

The pollen tube is a cellular system that plays a fundamental role during the process of fertilization in higher plants. Because it is so important, the pollen tube has been subjected to intensive studies with the aim of understanding its biology. The pollen tube represents a fascinating model for studying interactions between the internal cytoskeletal machinery, the membrane system, and the cell wall. These compartments, often studied as independent units, show several molecular interactions and can influence the structure and organization of each other. The way the cell wall is constructed, the dynamics of the endomembrane system, and functions of the cytoskeleton suggest that these compartments are a molecular "continuum," which represents a link between the extracellular environment and the pollen tube cytoplasm. Several experimental approaches have been used to understand how these interactions may translate the pollen-pistil interactions into differential processes of pollen tube growth.


Assuntos
Pólen/metabolismo , Membrana Celular/metabolismo , Parede Celular/metabolismo , Citoesqueleto/metabolismo , Exocitose , Membranas Intracelulares/metabolismo , Plantas/metabolismo , Pólen/ultraestrutura
16.
Eur J Cell Biol ; 67(3): 209-17, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7588877

RESUMO

Using anti-myosin antibodies, standard immunocytochemical techniques in conjunction with confocal scanning laser microscopy and colloidal gold immunoelectron microscopy we compare changes in the distribution patterns of myosin during the early stages of pollen hydration, germination, tube growth, and myosin associated with isolated vegetative nucleus and the generative cell in Nicotiana tabacum L. Furthermore, on the Western blots of pollen tube proteins, the antimyosin antibodies crossreact only with one polypeptide of approximately 174 kDa. Confocal immunofluorescence microscopy reveals that in hydrated pollen, myosin is discretely associated with the cytoplasmic organelles and numerous punctate structures present in the center of the pollen. Within 30 min following transfer of pollen into the germination medium, that is, with the onset of germination, the centrally located punctate structures are displaced, and we find accumulation of myosin-associated organelles towards one of the germinal apertures from which the pollen tube would emerge. Subsequently, after 45 min of germination with the emergence of germination structure, few punctate structures are detected in the vegetative cytoplasm while intense immunostain is detected just below the plasma membrane of the emerging pollen tube tip. In the older parts of both short and long pollen tubes after 90 to 120 min of pollen germination, few fluorescent structures were found in the pollen tubes, however, numerous punctate fluorescent spots were concentrated in the tip region over a distance of 2 to 3 microns below the plasma membrane of the tube tip. This is further substantiated by colloidal gold immunoelectron microscopy wherein clusters of gold particles are associated with vesicle-like structures in the tip region of the pollen tubes.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Germinação , Miosinas/isolamento & purificação , Nicotiana/ultraestrutura , Plantas Tóxicas , Pólen/ultraestrutura , Western Blotting , Núcleo Celular/ultraestrutura , Imunofluorescência , Ouro , Processamento de Imagem Assistida por Computador , Lasers , Microscopia Confocal , Microscopia Imunoeletrônica , Miosinas/imunologia , Pólen/química , Pólen/crescimento & desenvolvimento , Nicotiana/química , Nicotiana/citologia , Água
17.
J Cell Sci ; 108 ( Pt 3): 1117-25, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7622598

RESUMO

Nicotiana tabacum pollen tubes contain two high molecular weight polypeptides (about 400 kDa), which are specifically expressed during pollen germination and pollen tube growth in BK medium. The high molecular weight doublet resembles the dynein heavy chains in some biochemical properties. Sedimentation profiles of pollen tube extracts show that the high molecular weight bands have sedimentation coefficients of 22 S and 12 S, respectively. ATPase assay of sedimentation fractions shows an activity ten times higher when stimulated by the presence of bovine brain microtubules in fractions containing the 22 S high molecular weight polypeptide. Both these high molecular weight polypeptides can bind microtubules in an ATP-dependent fashion. A mouse antiserum to a synthetic peptide reproducing the sequence of the most conserved ATP-binding site among dynein heavy chains recognized the two high molecular weight polypeptides. Therefore these polypeptides have sequences immunologically related to the ATP binding sites of dynein heavy chains.


Assuntos
Dineínas/química , Nicotiana/química , Proteínas de Plantas/química , Plantas Tóxicas , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos , Sítios de Ligação , Encéfalo/metabolismo , Bovinos , Dineínas/genética , Dineínas/metabolismo , Imunoquímica , Técnicas In Vitro , Microtúbulos/metabolismo , Dados de Sequência Molecular , Peso Molecular , Peptídeos/síntese química , Peptídeos/química , Peptídeos/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pólen/química , Nicotiana/genética , Nicotiana/metabolismo
18.
Biol Cell ; 83(2-3): 179-84, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7549913

RESUMO

The specificity of four monoclonal antibodies, raised against mammalian ciliary axonemes, was determined by both immunofluorescence and immunoblot experiments. Three antibodies reacted with epitopes which are differentially located along axonemal length. Among these, antibody 3.12 recognized an epitope common to different dynein heavy chains, reacted only with tracheal cilia and specifically stained the proximal portion of the ciliary axoneme.


Assuntos
Anticorpos Monoclonais/imunologia , Cílios/imunologia , Animais , Bovinos , Cílios/química , Cílios/ultraestrutura , Técnicas Imunoenzimáticas , Técnicas In Vitro , Peso Molecular , Traqueia/ultraestrutura
19.
J Cell Biol ; 125(5): 1109-17, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8195292

RESUMO

To understand mechanisms of regulation of dynein activity along and around the axoneme we further characterized the "dynein regulatory complex" (drc). The lack of some axonemal proteins, which together are referred to as drc, causes the suppression of flagellar paralysis of radial spoke and central pair mutants. The drc is also an adapter involved in the ATP-insensitive binding of I2 and I3 inner dynein arms to doublet microtubules. Evidence supporting these conclusions was obtained through analyses of five drc mutants: pf2, pf3, suppf3, suppf4, and suppf5. Axonemes from drc mutants lack part of I2 and I3 inner dynein arms as well as subsets of seven drc components (apparent molecular weight from 29,000 to 192,000). In the absence of ATP-Mg, dynein-depleted axonemes from the same mutants bind I2 and I3 inner arms at both ATP-sensitive and -insensitive sites. At ATP-insensitive sites, they bind I2 and I3 inner arms to an extent that depends on the drc defect. This evidence suggested to us that the drc forms one binding site for the I2 and I3 inner arms on the A part of doublet microtubules.


Assuntos
Dineínas/metabolismo , Flagelos/metabolismo , Microtúbulos/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Chlamydomonas , Dineínas/genética , Eletroforese em Gel Bidimensional , Flagelos/ultraestrutura , Microtúbulos/ultraestrutura , Peso Molecular , Mutação , Ligação Proteica
20.
Minerva Med ; 85(3): 77-81, 1994 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-8196847

RESUMO

In normal subjects increasing atmospheres of absolute pressure (ATA) on the cardiopulmonary system, in a hyperbaric chamber, results in a marked diuresis and an increase of circulating concentration of atrial natriuretic peptide (ANP). The present investigation was designed to determine the effect of ATA in a group of 5 sodium-retaining cirrhotic patients on hydro-saline balance, renin-angiotensin-aldosterone system and ANP. After seven days on a 10 mEq sodium intake, each patient was studied on both a control and experimental (4-hour stay at 2-ATA in hyperbaric chamber) day. On each day, measurement of the following were obtained: plasma ANP, plasma renin activity (PRA) and aldosterone, electrolytes, creatinine clearance, volume and sodium and potassium urinary excretion. The increasing ATA lacked to induce both diuresis, natriuresis and increase in ANP plasma concentration. In these patients baseline, pre-hyperbaric, mean levels of PRA, aldosterone and ANP were 15.5 +/- 11.5 ng/ml/h, 808.4 +/- 360 pg/ml, 86 +/- 10.1 pg/ml, respectively, and were significantly elevated compared with normal range for control subjects without sodium restriction. In conclusion, increasing pressure at 2-ATA, in a hyperbaric chamber is unable to elicit both diuresis and natriuresis as well as modification on ANP and renin-angiotensin-aldo-sterone system in sodium-retaining cirrhotic patients.


Assuntos
Ascite/sangue , Ascite/fisiopatologia , Pressão Atmosférica , Fator Natriurético Atrial/sangue , Oxigenoterapia Hiperbárica , Cirrose Hepática/sangue , Cirrose Hepática/fisiopatologia , Natriurese/fisiologia , Idoso , Câmaras de Exposição Atmosférica , Feminino , Humanos , Pessoa de Meia-Idade , Renina/sangue , Fatores de Tempo
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