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1.
J Sci Food Agric ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38979953

RESUMO

BACKGROUND: Folic acid (FA), a synthetically produced compound analogous to vitamin B9, also referred to as vitamin folate, is an essential compound in human health and faces challenges in stability during food processing. This study explores the incorporation of FA into carboxymethylcellulose (CMC) nanofibers using electrospinning to enhance its stability. RESULTS: In this study, optimization of both electrospinning and solution parameters facilitated the fabrication of nanofibers. Furthermore, incorporating FA into CMC/polyethylene oxide (PEO) nanofibers resulted in thinner fibers, with an average diameter of 88 nm, characterized by a flat shape and smooth surface. Fourier transform infrared spectroscopic analysis demonstrated substantial hydrogen bonding interactions between FA and the polar groups present in CMC. This interaction contributed to an encapsulation efficiency of 94.5%, with a yield exceeding 87%. Thermal analysis highlighted mutual interference between CMC and PEO, with FA enhancing the thermal stability and reducing the melting temperatures and enthalpies of PEO, while also increasing the reaction heats of CMC. The encapsulated FA remained stable in acidic conditions, with only 6% degradation over 30 days, demonstrating the efficacy of CMC/PEO nanofibers in safeguarding FA against acidic environments. Moreover, the nanofibers provided a protective barrier against UV radiation, thereby preserving the stability of FA. CONCLUSION: This study emphasizes the efficacy of CMC/PEO nanofibers as a protective matrix against FA degradation. The findings indicate that this innovative approach could significantly diversify the applications of FA in food fortification, addressing concerns regarding its vulnerability to temperature and hydrolysis reactions during food processing. © 2024 Society of Chemical Industry.

2.
Biochim Biophys Acta Bioenerg ; 1859(2): 110-118, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29107655

RESUMO

Microcin J25 has two targets in sensitive bacteria, the RNA polymerase, and the respiratory chain through inhibition of cellular respiration. In this work, the effect of microcin J25 in E. coli mutants that lack the terminal oxidases cytochrome bd-I and cytochrome bo3 was analyzed. The mutant strains lacking cytochrome bo3 or cytochrome bd-I were less sensitive to the peptide. In membranes obtained from the strain that only expresses cytochrome bd-I a great ROS overproduction was observed in the presence of microcin J25. Nevertheless, the oxygen consumption was less inhibited in this strain, probably because the oxygen is partially reduced to superoxide. There was no overproduction of ROS in membranes isolated from the mutant strain that only express cytochrome bo3 and the inhibition of the cellular respiration was similar to the wild type. It is concluded that both cytochromes bd-I and bo3 are affected by the peptide. The results establish for the first time a relationship between the terminal oxygen reductases and the mechanism of action of microcin J25.


Assuntos
Bacteriocinas/farmacologia , Citocromos/biossíntese , Complexo de Proteínas da Cadeia de Transporte de Elétrons/biossíntese , Proteínas de Escherichia coli/biossíntese , Escherichia coli/enzimologia , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Oxirredutases/biossíntese , Grupo dos Citocromos b , Citocromos/genética , Complexo de Proteínas da Cadeia de Transporte de Elétrons/genética , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Oxirredutases/genética , Espécies Reativas de Oxigênio/metabolismo
3.
Scand J Med Sci Sports ; 26(2): 165-71, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25683194

RESUMO

This study analyzed the relationships between isometric as well as concentric maximum voluntary contraction (MVC) strength of the leg muscles and the times as well as speeds over different distances in 17 young short track speed skaters. Isometric as well as concentric single-joint MVC strength and multi-joint MVC strength in a stable (without skates) and unstable (with skates) condition were tested. Furthermore, time during maximum skating performances on ice was measured. Results indicate that maximum torques during eversion and dorsal flexion have a significant influence on skating speed. Concentric MVC strength of the knee extensors was higher correlated with times as well as speeds over the different distances than isometric MVC strength. Multi-joint MVC testing revealed that the force loss between measurements without and with skates amounts to 25%, while biceps femoris and soleus showed decreased muscle activity and peroneus longus, tibialis anterior, as well as rectus femoris exhibited increased muscle activity. The results of this study depict evidence that the skating times and speeds are primarily influenced by concentric MVC strength of the leg extensors. To be able to transfer the strength onto ice in an optimal way, it is necessary to stabilize the knee and ankle joints.


Assuntos
Desempenho Atlético/fisiologia , Força Muscular , Músculo Esquelético/fisiologia , Patinação/fisiologia , Adolescente , Articulação do Tornozelo/fisiologia , Criança , Eletromiografia , Teste de Esforço , Feminino , Humanos , Contração Isométrica , Articulação do Joelho/fisiologia , Extremidade Inferior , Masculino , Músculo Quadríceps/fisiologia , Torque
4.
Eur J Pediatr ; 174(1): 23-32, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24953377

RESUMO

UNLABELLED: Renovascular hypertension accounts for 5-10 % of hypertension cases in children; there is currently no consensus on treatment. Here, we report on our clinical experience with this disease and outline the different pathways in which to investigate it. We report retrospectively on ten children diagnosed with renovascular hypertension at the University Hospital of Nantes from 2001 to 2012. The main findings were obtained by fortuitous screening of children aged 2 months to 14 years old with neurofibromatosis (n = 2) and fibromuscular dysplasia (n = 8). The hypertension was always severe yet asymptomatic. Lesions were complicated in nine out of ten cases and included bilateral, multiple, mid-aortic syndrome and aneurysm. Doppler ultrasound associated with computed tomography allowed for a precise diagnosis in seven out of ten cases. Where ambiguities persisted, they were highlighted by arteriography, the gold standard investigation. Medical treatment was insufficient, leading to invasive procedures in nine out of ten children: 2 nephrectomies, 2 autotransplantations, and 21 repetitive percutaneous transluminal angioplasties. After invasive procedures, blood pressure control improved in four cases and was resolved in three. CONCLUSION: Arteriography remains to be the gold standard technique for renovascular hypertension in children and can be combined with angioplasty when medical treatment is rendered obsolete. The role of computed tomography is controversial. Despite the heterogeneity of the children studied, we present a general medical and therapeutic management pathway for the treatment of this disease.


Assuntos
Hipertensão Renovascular/diagnóstico , Hipertensão Renovascular/terapia , Adolescente , Angiografia/métodos , Angioplastia , Criança , Pré-Escolar , Feminino , Displasia Fibromuscular/complicações , Humanos , Lactente , Masculino , Neurofibromatose 1/complicações , Sistema Renina-Angiotensina/fisiologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia Doppler
5.
Eur J Neurosci ; 37(7): 1120-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23351116

RESUMO

Although there is increasing knowledge about how visual and tactile cues from the hands are integrated, little is known about how self-generated hand movements affect such multisensory integration. Visuo-tactile integration often occurs under highly dynamic conditions requiring sensorimotor updating. Here, we quantified visuo-tactile integration by measuring cross-modal congruency effects (CCEs) in different bimanual hand movement conditions with the use of a robotic platform. We found that classical CCEs also occurred during bimanual self-generated hand movements, and that such movements lowered the magnitude of visuo-tactile CCEs as compared to static conditions. Visuo-tactile integration, body ownership and the sense of agency were decreased by adding a temporal visuo-motor delay between hand movements and visual feedback. These data show that visual stimuli interfere less with the perception of tactile stimuli during movement than during static conditions, especially when decoupled from predictive motor information. The results suggest that current models of visuo-tactile integration need to be extended to account for multisensory integration in dynamic conditions.


Assuntos
Imagem Corporal , Destreza Motora , Percepção do Tato/fisiologia , Percepção Visual/fisiologia , Adulto , Retroalimentação Sensorial , Feminino , Humanos , Masculino , Tempo de Reação , Robótica
6.
Mol Genet Metab ; 110(1-2): 106-10, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23751327

RESUMO

INTRODUCTION: Patients with methylmalonic acidemia (MMA) may develop many complications despite medical treatment, in particular, severe central nervous system damage and chronic kidney disease (CKD). A kidney transplant may partially correct the metabolic dysfunctions. Liver, kidney and combined liver-kidney transplantations have been advocated but no guidelines are available to identify the most suitable organ to transplant. PATIENTS AND METHODS: Four patients with MMA (mut° phenotype) received a kidney graft because of repeated metabolic decompensations, with progression to CKD in 3 patients (end-stage kidney disease in two patients and CKD stage III in one patient with an estimated glomerular filtration rate [eGFR] of 40ml/min/1.73m(2)) but normal renal function in one (eGFR of 93ml/min/1.73m(2)) before transplantation. RESULTS: The medium age at transplantation was 7.9y (5-10.2) and the median follow-up was 2.8years (1.8-4.6). Renal transplantation improved the relevant metabolic parameters in 4/4 patients and renal function in the patients with CKD. Plasma and urinary MMA levels immediately decreased and remained normal or subnormal (mean values of plasma MMA before transplantation 1530µmol/L versus 240µmol/L after transplantation, and mean values of urine MMA before transplantation 4700mmol/mol creatinine versus 2300mmol/mol creatinine after transplantation). No further acute metabolic decompensation was observed and protein-intake was increased from 0.60 to 0.83g/Kg/day. One patient transplanted at age 9.7years developed a hepatoblastoma at age 11years with subsequent neurological complications and eventually died. The three other patients are alive. Two of them remained neurologically stable. The 3rd patient who displayed choreoathetosis transiently improved his neurological condition immediately after transplantation and then remained stable. CONCLUSION: Kidney transplantation represents an interesting alternative therapeutic option in methylmalonic aciduria, for renal complications but also as a "cellular therapy" that may significantly reduce metabolic decompensations and hospitalizations. However, further neurological impairment remains possible.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/terapia , Transplante de Rim , Transplante de Fígado , Doenças Metabólicas/terapia , Insuficiência Renal Crônica/terapia , Erros Inatos do Metabolismo dos Aminoácidos/sangue , Erros Inatos do Metabolismo dos Aminoácidos/genética , Erros Inatos do Metabolismo dos Aminoácidos/patologia , Erros Inatos do Metabolismo dos Aminoácidos/urina , Terapia Baseada em Transplante de Células e Tecidos , Criança , Progressão da Doença , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Doenças Metabólicas/genética , Ácido Metilmalônico/sangue , Ácido Metilmalônico/urina , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/patologia
7.
Exp Brain Res ; 228(2): 173-81, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23665753

RESUMO

In real-life situations, we are often required to recognize our own movements among movements originating from other people. In social situations, these movements are often correlated (for example, when dancing or walking with others) adding considerable difficulty to self-recognition. Studies from visual search have shown that visual attention can selectively highlight specific features to make them more salient. Here, we used a novel visual search task employing virtual reality and motion tracking to test whether visual attention can use efferent information to enhance self-recognition of one's movements among four or six moving avatars. Active movements compared to passive movements allowed faster recognition of the avatar moving like the subject. Critically, search slopes were flat for the active condition but increased for passive movements, suggesting efficient search for active movements. In a second experiment, we tested the effects of using the participants' own movements temporally delayed as distractors in a self-recognition discrimination task. We replicated the results of the first experiment with more rapid self-recognition during active trials. Importantly, temporally delayed distractors increased reaction times despite being more perceptually different than the spatial distractors. The findings demonstrate the importance of agency in self-recognition and self-other discrimination from movement in social settings.


Assuntos
Atenção/fisiologia , Movimento/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
8.
Nat Genet ; 14(3): 345-7, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8896569

RESUMO

Hirschsprung disease (HSCR, aganglionic megacolon) is a common congenital malformation leading to bowel obstruction, with an incidence of 1/5,000 live births. It is characterized by the absence of intrinsic ganglion cells in the myenteric and submucosal plexuses along variable lengths of the gastrointestinal tract. As enteric neurons are derived from the vagal neural crest, HSCR is regarded as a neurocristopathy. On the basis of a skewed sex-ratio (M/F = 4/1) and a risk to relatives much higher than the incidence in the general population, HSCR has long been regarded as a sex-modified multifactorial disorder. Accordingly, segregation analysis suggested an incompletely penetrant dominant inheritance in HSCR families with aganglionosis extending beyond the sigmoid colon. We and others have mapped a dominant gene for HSCR to chromosome 10q11.2 and have ascribed the disease to mutations in the RET proto-oncogene. However, the lack of genotype-phenotype correlation, the low penetrance and the sex-dependent effect of RET mutations supported the existence of one or more modifier gene(s) in familial HSCR. In addition, thus far, RET mutations only accounted for 50% and 15-20% of familial and sporadic HSCR patients, respectively. RET encodes a tyrosine kinase receptor whose ligand was unknown. Recently, the Glial cell line-derived neurotrophic factor (GDNF) has been identified to be a ligand for RET. Moreover, Gdnf-/- knockout mutant mice display congenital intestinal aganglionosis and renal agenesis, a phenotype very similar to the Ret-/- mouse. These data prompted us to hypothesize that mutations of the gene encoding GDNF could either cause or modulate the HSCR phenotype in some cases.


Assuntos
Proteínas de Drosophila , Mutação em Linhagem Germinativa , Doença de Hirschsprung/genética , Fatores de Crescimento Neural , Proteínas do Tecido Nervoso/genética , Feminino , Fator Neurotrófico Derivado de Linhagem de Célula Glial , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial , Humanos , Masculino , Linhagem , Fenótipo , Polimorfismo Conformacional de Fita Simples , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-ret , Receptores Proteína Tirosina Quinases/genética , Análise de Sequência de DNA
9.
Nat Genet ; 26(3): 332-5, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11062474

RESUMO

Triple-A syndrome (MIM 231550; also known as Allgrove syndrome) is an autosomal recessive disorder characterized by adrenocorticotropin hormone (ACTH)-resistant adrenal insufficiency, achalasia of the oesophageal cardia and alacrima. Whereas several lines of evidence indicate that triple-A syndrome results from the abnormal development of the autonomic nervous system, late-onset progressive neurological symptoms (including cerebellar ataxia, peripheral neuropathy and mild dementia) suggest that the central nervous system may be involved in the disease as well. Using fine-mapping based on linkage disequilibrium in North African inbred families, we identified a short ancestral haplotype on chromosome 12q13 (<1 cM), sequenced a BAC contig encompassing the triple-A minimal region and identified a novel gene (AAAS) encoding a protein of 547 amino acids that is mutant in affected individuals. We found five homozygous truncating mutations in unrelated patients and ascribed the founder effect in North African families to a single splice-donor site mutation that occurred more than 2,400 years ago. The predicted product of AAAS, ALADIN (for alacrima-achalasia-adrenal insufficiency neurologic disorder), belongs to the WD-repeat family of regulatory proteins, indicating a new disease mechanism involved in triple-A syndrome. The expression of the gene in both neuroendocrine and cerebral structures points to a role in the normal development of the peripheral and central nervous systems.


Assuntos
Anormalidades Múltiplas/genética , Insuficiência Adrenal/genética , Cromossomos Humanos Par 12/genética , Acalasia Esofágica/genética , Genes , Doenças do Sistema Nervoso/genética , Proteínas/genética , Xeroftalmia/genética , África do Norte , Motivos de Aminoácidos , Sequência de Aminoácidos , Cromossomos Artificiais Bacterianos/genética , Códon/genética , Consanguinidade , Análise Mutacional de DNA , Evolução Molecular , Etiquetas de Sequências Expressas , Haplótipos , Humanos , Desequilíbrio de Ligação , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/fisiologia , Complexo de Proteínas Formadoras de Poros Nucleares , Linhagem , Mutação Puntual , Proteínas/química , Proteínas/fisiologia , Sequências Repetitivas de Aminoácidos , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Síndrome
10.
Environ Sci Pollut Res Int ; 30(9): 24088-24100, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36334206

RESUMO

The role of nanozinc source (nanohydrozincite: nHZ; nanozinc oxide: nZO) on the performance of alkali-activated slag (AAS) was explored for the first time in the present work. The results showed that nHZ with different contents (0.5, 1.0, and 1.5 wt%) retards the early hydration rate of AAS, whereas nZO showed the lowest retardation effect. Zn(OH)2 is the main retarder inside AAS-nZO and AAS-nHZ, which consumes the dissolved Ca2+ (responsible for the early hardening of AAS) from slag to yield calcium zincate hydrate (CZH). The high retardation rate of nHZ is originated from its high affinity to consume much Ca2+ through the formation of additional pirssonite (Na2CO3.CaCO3.2H2O) double salt. Although adding nHZ induced the drying shrinkage of AAS, it improved the later compressive strengths (28 to 365 days), especially at low nHZ content (0.5 wt%), via the formation of CASH with lower Ca/Si ratio and higher binding capacity compared to that formed inside AAS and AAS-nZO. A further research is needed to reduce the drying shrinkage and to accelerate the early strength of AAS containing nHZ.


Assuntos
Álcalis , Cálcio , Força Compressiva , Dessecação , Óxidos
11.
Conscious Cogn ; 21(3): 1355-64, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22832215

RESUMO

Recent studies have shown the importance of integrating multisensory information in the body representation for constituting self-consciousness. However, one idea that has received only scant attention is that our body representation is also constituted by knowledge of bodily visual characteristics (i.e. 'what I look like'). Here in two experiments we used a full body crossmodal congruency task in which visual distractors were presented on a photograph of the participant, another person, who was either familiar or unfamiliar, or an object. Results revealed that during the 'self-condition' CCEs were enhanced compared to the 'other condition'. The CCE was similar for unfamiliar and familiar others. CCEs for the object condition were significantly smaller. The results show that presentation of an irrelevant image of a body affects multimodal processing and that the effect is enhanced when that image is of the self. The results hold intriguing implications for body representation in social situations.


Assuntos
Imagem Corporal/psicologia , Percepção do Tato , Percepção Visual , Estado de Consciência , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação , Reconhecimento Psicológico , Adulto Jovem
12.
Cells Tissues Organs ; 191(3): 203-12, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19776547

RESUMO

Experimentation with the progenitor/stem cells in adult prostate epithelium can be inconvenient due to a tight time line from tissue acquisition to cell isolation and to downstream experiments. To circumvent this inconvenience, we developed a simple technical procedure for culturing epithelial cells derived from human prostate tissue. In this study, benign prostate tissue was enzymatically digested and fractionated into epithelium and stroma, which were then cultured in the medium designed for prostate epithelial and stromal cells, respectively. The cultured cells were analyzed by immunocytochemical staining and flow cytometry. Prostate tissue-regenerating capacity of cultured cells in vitro was determined by co-culturing epithelial and stromal cells in dihydrotestosterone-containing RPMI. Cell lineages in formed acini-like structures were determined by immunohistochemistry. The culture of epithelial cells mainly consisted of basal cells. A minor population was negative for known lineage markers and positive for CD133. The culture also contained cells with high activity of aldehyde dehydrogenase. After co-culturing with stromal cells, the epithelial cells were able to form acini-like structures containing multiple cell lineages. Thus, the established culture of prostate epithelial cells provides an alternative source for studying progenitor/stem cells of prostate epithelium.


Assuntos
Células Epiteliais/citologia , Próstata , Regeneração , Antígeno AC133 , Adulto , Células-Tronco Adultas/citologia , Células-Tronco Adultas/fisiologia , Aldeído Desidrogenase/metabolismo , Antígenos CD/biossíntese , Diferenciação Celular , Linhagem da Célula , Separação Celular , Células Cultivadas , Técnicas de Cocultura/métodos , Meios de Cultura/química , Di-Hidrotestosterona/química , Células Epiteliais/fisiologia , Glicoproteínas/biossíntese , Humanos , Masculino , Técnicas de Cultura de Órgãos/métodos , Peptídeos , Próstata/citologia , Próstata/fisiologia , Células Estromais/citologia , Células Estromais/fisiologia
13.
J Neuroradiol ; 37(4): 220-30, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20378176

RESUMO

OBJECTIFS: To propose a MRI cerebellar algorithm that may be applied to guide genetic/malformative or biochemical investigations for patients with cerebellar ataxia. PATIENTS AND METHODS: Cerebral MRI of 158 patients with cerebellar ataxia and no supratentorial abnormality were examined according to a new categorization system based on posterior fossa imaging. The clinical and radiological findings were confronted to biochemical and/or genetic results using the MR cerebellar algorithm. Seven groups of cerebellar MRI pattern were described: vermian dysgenesis (n=27), cerebellar hypoplasia (n=15), hemispheric cerebellar dysgenesis (n=6), unilateral hemispheric atrophy (n=5), global cerebellar atrophy (n=84), signal abnormalities (n=11) and normal MRI (n=10). Cerebellar hypoplasia, vermian dysgenesis and hemispheric cerebellar dysgenesis groups were classified as malformative disorders. Global atrophy and signal abnormality groups were classified as metabolic disorders. RESULTS: In the vermian dysgenesis group, a specific genetic diagnosis was obtained in eight children (8/27) and all of the mutated genes (AHI1 (JBS3), CEP290 (JBS5), TMEM67 (JBS6), and RPGRIP1L (JBS7)) are involved in primary cilia function. In the group of pontocerebellar hypoplasia specific genetic diagnosis was obtained in one patient (PCH2) (1/15). Thus, nine of 42 children classified as malformative disorder had a molecular diagnosis. Global atrophy and signal abnormality groups were classified as metabolic disorders, specific biochemical was obtained in 46/95 children. In global atrophy group, respiratory chain deficiency was diagnosed in 18 children (18/84). In 21 children a congenital disorders of glycosylation type 1a (CDG Ia) was diagnosed (21/84) and infantile neuroaxonale dystrophy (INAD) was diagnosed in one child. In signal abnormalities group, specific biochemical diagnosis was obtained in six out of 11 children, five children with respiratory chain deficiency and one child with sulphite oxidase deficiency. In hemispheric cerebellar dysgenesis and normal MRI groups, no biological diagnosis was found for any of the patients. In the group of unilateral hemispheric atrophy, we hypothesized a clastic prenatal injury. CONCLUSION: The proposed MR cerebellar algorithm was useful to guide genetic/malformative or biochemical investigations, allowing an etiological diagnosis in 55 children.


Assuntos
Ataxia Cerebelar/patologia , Cerebelo/patologia , Fossa Craniana Posterior/patologia , Adolescente , Algoritmos , Cerebelo/anormalidades , Criança , Pré-Escolar , Fossa Craniana Posterior/anormalidades , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Seleção de Pacientes
14.
Science ; 244(4910): 1344-6, 1989 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-2734614

RESUMO

The possibility of using the vascular endothelial cell as a target for gene replacement therapy was explored. Recombinant retroviruses were used to transduce the lacZ gene into endothelial cells harvested from mongrel dogs. Prosthetic vascular grafts seeded with the genetically modified cells were implanted as carotid interposition grafts into the dogs from which the original cells were harvested. Analysis of the graft 5 weeks after implantation revealed genetically modified endothelial cells lining the luminal surface of the graft. This technology could be used in the treatment of atherosclerosis disease and the design of new drug delivery systems.


Assuntos
Prótese Vascular , Endotélio Vascular/citologia , Transfecção , Animais , Artérias Carótidas/cirurgia , Células Cultivadas , Cães , Endotélio Vascular/fisiologia , Endotélio Vascular/transplante , Vetores Genéticos , Retroviridae/genética
15.
Nat Commun ; 10(1): 2401, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160580

RESUMO

Neurotechnology attempts to develop supernumerary limbs, but can the human brain deal with the complexity to control an extra limb and yield advantages from it? Here, we analyzed the neuromechanics and manipulation abilities of two polydactyly subjects who each possess six fingers on their hands. Anatomical MRI of the supernumerary finger (SF) revealed that it is actuated by extra muscles and nerves, and fMRI identified a distinct cortical representation of the SF. In both subjects, the SF was able to move independently from the other fingers. Polydactyly subjects were able to coordinate the SF with their other fingers for more complex movements than five fingered subjects, and so carry out with only one hand tasks normally requiring two hands. These results demonstrate that a body with significantly more degrees-of-freedom can be controlled by the human nervous system without causing motor deficits or impairments and can instead provide superior manipulation abilities.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Dedos/diagnóstico por imagem , Movimento/fisiologia , Músculo Esquelético/diagnóstico por imagem , Polidactilia/diagnóstico por imagem , Adolescente , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Córtex Cerebral/fisiologia , Feminino , Dedos/fisiologia , Neuroimagem Funcional , Mãos/diagnóstico por imagem , Mãos/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Polidactilia/fisiopatologia
16.
J Urol ; 179(2): 674-9; discussion 679, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18082208

RESUMO

PURPOSE: Antibiotic prophylaxis is given to children at risk for urinary tract infection. However, evidence concerning its effectiveness in grade I to III vesicoureteral reflux is lacking. The objective of this study was to determine whether antibiotic prophylaxis reduces the incidence of urinary tract infection in young children with low grade vesicoureteral reflux. MATERIALS AND METHODS: Children 1 month to 3 years old with grade I to III vesicoureteral reflux were assigned randomly to receive daily cotrimoxazole or no treatment, and followed for 18 months. A urinary tract infection constituted an exit criterion. Infection-free survival rates were calculated using the Kaplan-Meier method and compared using the log rank test. RESULTS: A total of 225 children were enrolled in the study. Distribution of gender, age at inclusion and reflux grade were similar between the 2 groups. There was no significant difference in the occurrence of urinary tract infection between the 2 groups (17% vs 26%, p = 0.2). However, a significant association was found between treatment and patient gender (p = 0.017). Prophylaxis significantly reduced urinary tract infection in boys (p = 0.013), most notably in boys with grade III vesicoureteral reflux (p = 0.042). CONCLUSIONS: These data suggest that antibiotic prophylaxis does not reduce the overall incidence of urinary tract infection in children with low grade vesicoureteral reflux. However, such a strategy may prevent further urinary tract infection in boys with grade III reflux.


Assuntos
Anti-Infecciosos Urinários/uso terapêutico , Antibioticoprofilaxia , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Infecções Urinárias/etiologia , Infecções Urinárias/prevenção & controle , Refluxo Vesicoureteral/complicações , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Lactente , Masculino , Estudos Prospectivos , Prevenção Secundária , Fatores Sexuais , Resultado do Tratamento
17.
Arch Pediatr ; 25(2): 118-125, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29395881

RESUMO

AIM: Identifying early clinical and biological factors associated with severe forms of postdiarrheal hemolytic uremic syndrome (D+HUS) that may help practitioners determine appropriate treatment. METHODS: This retrospective study was conducted in 49 children with D+HUS between 2001 and 2011. Severe forms were defined as occurrence of one of the following conditions: death, major neurological involvement, cardiovascular involvement, and/or the presence of sequelae (neurological, cardiovascular, pancreatic, or renal). RESULTS: During the acute phase, 35 children exhibited at least one type of extrarenal involvement including 13 severe forms with a median delayed occurrence after admission of 4.5 days (range: 1-8) for comatose children and 5 days (range: 2-6) for cardiovascular involvement; 32 children required dialysis and three died. In multivariate analysis, (i) major neurological involvement (n=13), (ii) dialysis (n=32), and (iii) sequelae (n=12) were associated with (i) fever during the prodromal phase requiring dialysis at admission, (ii) C-reactive protein level (CRP) >22mg/L at admission, and (iii) major neurological involvement and a white blood cell count (WBC)>20×103/mm3 during the acute stage, respectively. CONCLUSIONS: D+HUS is a multiorgan disease with a delayed occurrence of life-threatening extrarenal organ involvement. Severe forms appear to be associated with early biological and clinical inflammatory parameters.


Assuntos
Diarreia/complicações , Síndrome Hemolítico-Urêmica/complicações , Insuficiência de Múltiplos Órgãos/etiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
18.
J Clin Invest ; 91(5): 2049-57, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8098045

RESUMO

The subtype and the expression of the alpha 2-adrenergic receptor were investigated in the normal mucosa from human intestine by means of radioligand binding, RNase mapping, and measurement of adenylate cyclase activity. The study of the binding of the alpha 2-adrenergic antagonist, [3H]RX821002, to epithelial cell membranes indicated the existence of a single class of noninteracting sites displaying a high affinity for the radioligand (Kd = 1.1 +/- 0.5 nM). The rank order of potency of antagonists to inhibit [3H]RX821002 binding (RX821002 > yohimbine = rauwolscine > phentolamine approximately idazoxan >> chlorpromazine > prazosin) suggested that the receptor is of the alpha 2A subtype. A conclusion which is confirmed by the fact that only alpha 2C10 transcripts were found in the human intestine mucosa. Competition curves with (-)-norepinephrine demonstrated that 60% of the receptor population exhibited high affinity for agonists. This high-affinity state was abolished by the addition of GTP plus Na+ or by prior treatment of the membranes with pertussis toxin indicating it corresponded to G protein-coupled receptors. [32P]ADP-ribosylation and immunoblotting experiments identified two pertussis toxin-sensitive G proteins corresponding to Gi2 and Gi3. The study of the distribution of the receptor indicated that (a) the proximal colon is the intestine segment exhibiting the highest receptor density and (b) the receptor is predominantly expressed in crypts and is preferentially located in the basolateral membrane of the polarized cell. The distribution of the receptor along the crypt-surface axis of the colon mucosa can be correlated with a higher level of alpha 2C10-specific mRNA and a higher efficiency of UK14304 to inhibit adenylate cyclase in crypt cells.


Assuntos
Antagonistas Adrenérgicos alfa/metabolismo , Dioxanos/metabolismo , Mucosa Intestinal/metabolismo , Receptores Adrenérgicos alfa/metabolismo , Adenosina Difosfato Ribose/metabolismo , Toxina Adenilato Ciclase , Inibidores de Adenilil Ciclases , Agonistas alfa-Adrenérgicos/farmacologia , Antagonistas Adrenérgicos alfa/farmacologia , Ligação Competitiva , Tartarato de Brimonidina , Membrana Celular/metabolismo , Colo/metabolismo , Duodeno/metabolismo , Epinefrina/farmacologia , Epitélio/metabolismo , Humanos , Idazoxano/análogos & derivados , Cinética , Microvilosidades/metabolismo , NAD/metabolismo , Especificidade de Órgãos , Toxina Pertussis , Quinoxalinas/farmacologia , RNA Mensageiro/metabolismo , Receptores Adrenérgicos alfa/análise , Fatores de Virulência de Bordetella/metabolismo
19.
J Clin Invest ; 105(5): 673-81, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10712439

RESUMO

Mucolipidosis IIIC, or variant pseudo-Hurler polydystrophy, is an autosomal recessive disease of lysosomal hydrolase trafficking. Unlike the related diseases, mucolipidosis II and IIIA, the enzyme affected in mucolipidosis IIIC (N-Acetylglucosamine-1-phosphotransferase [GlcNAc-phosphotransferase]) retains full transferase activity on synthetic substrates but lacks activity on lysosomal hydrolases. Bovine GlcNAc-phosphotransferase has recently been isolated as a multisubunit enzyme with the subunit structure alpha(2)beta(2)gamma(2). We cloned the cDNA for the human gamma-subunit and localized its gene to chromosome 16p. We also showed, in a large multiplex Druze family that exhibits this disorder, that MLIIIC also maps to this chromosomal region. Sequence analysis of the gamma-subunit cDNA in patients from 3 families identified a frameshift mutation, in codon 167 of the gamma subunit, that segregated with the disease, indicating MLIIIC results from mutations in the phosphotransferase gamma-subunit gene. This is to our knowledge the first description of the molecular basis for a human mucolipidosis and suggests that the gamma subunit functions in lysosomal hydrolase recognition.


Assuntos
Lisossomos/metabolismo , Mucolipidoses/genética , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Sequência de Aminoácidos , Sequência de Bases , Cromossomos Humanos Par 16 , Clonagem Molecular , Feminino , Fibroblastos , Mutação da Fase de Leitura , Ligação Genética , Humanos , Escore Lod , Lisossomos/enzimologia , Masculino , Dados de Sequência Molecular , Mucolipidoses/etiologia , Linhagem , RNA Mensageiro/metabolismo , Análise de Sequência , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo
20.
Arch Pediatr ; 24(10): 1019-1028, 2017 Oct.
Artigo em Francês | MEDLINE | ID: mdl-28927772

RESUMO

Antiglomerular basement membrane glomerulonephritis is a rare autoimmune disease characterized by rapidly progressive glomerulonephritis that may be associated with pulmonary hemorrhage (Goodpasture syndrome). The disease is caused by autoantibodies (classically IgGs) directed against the α3 subunit of type IV collagen. This is a rare disease in the adult population and extremely rare in children, with a reported cumulative annual incidence at 1/106 people/year. Among scarce reported pediatric cases (n=31), most are girls (M/F sex ratio, 1:4), and the mean age at diagnoses is 9.2±4.6 years. A medical diagnosis is an emergency and is based on the identification of specific antibodies in the serum, and pathognomonic linear fixation of IgGs along the glomerular basement membrane. Without appropriate treatment, the disease is generally fulminant, and patient and kidney survival is poor. Indeed, glomerular function strongly correlates with histological lesions. The current guidelines recommend the use of plasma exchanges and immunosuppressive drugs. For the past few years, alternative therapeutics such as specific anti-B-cell antibodies (rituximab) or specific extrarenal cleansing such as immunoadsorption have been successfully used in adults. Immunoadsorptions (IAs) can remove pathogenic IgGs from the circulation and do not require plasma infusions, contrary to plasma exchanges. In this review, we discuss the key points of antiglomerular basement membrane glomerulonephritis diagnosis and conventional or alternative therapeutics.


Assuntos
Doença Antimembrana Basal Glomerular/terapia , Doença Antimembrana Basal Glomerular/diagnóstico , Doença Antimembrana Basal Glomerular/etiologia , Criança , Humanos
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