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1.
J Endocrinol Invest ; 45(5): 941-961, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34973154

RESUMO

PURPOSE: The current randomized, double-blind, placebo-controlled clinical trial addressed the effects on penile erectile function of relatively high daily oral doses (6 g/day) of L-ARG for 3 months (N = 51) compared to placebo (N = 47), in patients with vasculogenic ED, with comparison between mild-moderate and severe vasculogenic ED. METHODS: The outcome measures included IIEF-6 score and cavernous arteries peak systolic flow velocity (PSV) at dynamic penile duplex ultrasonography (PDU). RESULTS: L-ARG supplementation for 3 months significantly increased IIEF-6 score in the overall cohort (p < 0.0001) and in subgroups of patients with mild-moderate (p < 0.0001) and severe (p = 0.007) vasculogenic ED; PSV was significantly increased in the overall cohort (p < 0.0001) and in patients with mild-moderate (p < 0.0001), but not severe vasculogenic ED. At study completion, 74% of patients improved ED degree category, although only 24% of patients, mainly belonging to the baseline category of mild ED, reached IIEF-6 scores compatible with absence of ED; moreover, 20% of patients, exclusively belonging to the baseline category of mild-moderate vasculogenic ED, reached PSV values compatible with absence of ED. CONCLUSION: The results of the current study demonstrated that supplementation with relatively high doses of L-ARG as a single compound for 3 months significantly improved penile erectile function, assessed by both IIEF-6 score and PSV at dynamic PDU in patients with mild-moderate, and improved IIEF-6 score, but not PSV, in patients with severe vasculogenic ED, therefore suggesting that L-ARG might be an alternative treatment in mild-moderate vasculogenic ED patients experiencing adverse effects or with contraindications for chronic treatment with PDE5i compounds.


Assuntos
Disfunção Erétil , Arginina , Suplementos Nutricionais , Método Duplo-Cego , Disfunção Erétil/tratamento farmacológico , Humanos , Masculino , Ereção Peniana , Pênis/irrigação sanguínea , Resultado do Tratamento
2.
Neurogastroenterol Motil ; 23(8): 745-e331, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21689210

RESUMO

BACKGROUND: Bromelain (BR) is a cysteine protease with inhibitory effects on intestinal secretion and inflammation. However, its effects on intestinal motility are largely unexplored. Thus, we investigated the effect of this plant-derived compound on intestinal contractility and transit in mice. METHODS: Contractility in vitro was evaluated by stimulating the mouse isolated ileum, in an organ bath, with acetylcholine, barium chloride, or electrical field stimulation. Motility in vivo was measured by evaluating the distribution of an orally administered fluorescent marker along the small intestine. Transit was also evaluated in pathophysiologic states induced by the pro-inflammatory compound croton oil or by the diabetogenic agent streptozotocin. KEY RESULTS: Bromelain inhibited the contractions induced by different spasmogenic compounds in the mouse ileum with similar potency. The antispasmodic effect was reduced or counteracted by the proteolytic enzyme inhibitor, gabexate (15 × 10(-6) mol L(-1) ), protease-activated receptor-2 (PAR-2) antagonist, N(1) -3-methylbutyryl-N(4) -6-aminohexanoyl-piperazine (10(-4) mol L(-1) ), phospholipase C (PLC) inhibitor, neomycin (3 × 10(-3) mol L(-1) ), and phosphodiesterase 4 (PDE4) inhibitor, rolipram (10(-6) mol L(-1) ). In vivo, BR preferentially inhibited motility in pathophysiologic states in a PAR-2-antagonist-sensitive manner. CONCLUSIONS & INFERENCES: Our data suggest that BR inhibits intestinal motility - preferentially in pathophysiologic conditions - with a mechanism possibly involving membrane PAR-2 and PLC and PDE4 as intracellular signals. Bromelain could be a lead compound for the development of new drugs, able to normalize the intestinal motility in inflammation and diabetes.


Assuntos
Ananas/enzimologia , Bromelaínas/farmacologia , Motilidade Gastrointestinal/efeitos dos fármacos , Trânsito Gastrointestinal/efeitos dos fármacos , Acetilcolina/farmacologia , Animais , Compostos de Bário/farmacologia , Bromelaínas/metabolismo , Células CACO-2 , Cloretos/farmacologia , Agonistas Colinérgicos/farmacologia , Óleo de Cróton/farmacologia , Diabetes Mellitus Experimental/fisiopatologia , Estimulação Elétrica , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Ileíte/induzido quimicamente , Ileíte/fisiopatologia , Masculino , Camundongos , Contração Muscular/efeitos dos fármacos , Peptídeos/metabolismo , Receptor PAR-1/antagonistas & inibidores , Receptor PAR-2/antagonistas & inibidores
3.
Lymphology ; 38(1): 9-15, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15856680

RESUMO

The purpose of this methods paper is to offer pediatricians and nuclear medicine physicians a diagnostic protocol for performing lymphoscintigraphy in newborns that may be useful for enhancing diagnosis and management of newborns with congenital lymphatic abnormalities. Indications for lymphoscintigraphy, choice of tracer, optimal dose, routes of administration, methods of data acquisition, timing, and interpretation of results for newborns are presented and discussed.


Assuntos
Linfedema/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Linfedema/etiologia , Masculino , Radiometria , Cintilografia , Sensibilidade e Especificidade , Tecnécio
4.
Lymphology ; 37(1): 22-30, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15109074

RESUMO

We report on three infants with congenital chylothorax (CC) and congenital pulmonary lymphangiectasia (CPL). CPL appears to be a characteristic pathological finding in CC. Through the use of lymphoscintigraphy and computed tomography, this study suggests that CC and CPL are strongly correlated entities and that the dysplasia of the lymphatic system results in a pulmonary lymphatic obstruction sequence. The initial microscopic dilatation of the lymph channels may lead to progressive weeping of lymphatics and, consequently, to pleural effusion. Non-Immune Hydrops Fetalis (NIHF) may be the final consequence of impaired systemic venous return and may help to explain pleural-pulmonary involvement in this generalized lymph-vessel malformation syndrome.


Assuntos
Anormalidades Múltiplas/diagnóstico por imagem , Quilotórax/congênito , Hidropisia Fetal/diagnóstico por imagem , Pneumopatias/congênito , Linfangiectasia/congênito , Quilotórax/diagnóstico por imagem , Feminino , Humanos , Lactente , Recém-Nascido , Pneumopatias/diagnóstico por imagem , Linfangiectasia/diagnóstico por imagem , Linfocintigrafia , Masculino , Tomografia Computadorizada por Raios X
6.
Clin Nutr ; 21(5): 379-84, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12381334

RESUMO

In the last few years, a variety of experimental and clinical studies concerning the formation, metabolism, and cellular effects of cholesterol oxidation products (COPs) have been carried out. Nevertheless, a substantial lack of knowledge exists regarding the possible intake of these compounds by the newborn through human and/or adapted formula milk. As far as the pathological role of COPs is concerned, exhaustive studies have shown that since dietary COPs are cytotoxic and atherotoxic, they may lead to adverse effects on health. The aim of this study was to investigate the possible development of cholesterol oxidation in adapted formula and in human milk by comparing the main cholesterol oxidation biomarker (7-ketocholesterol) concentration in both. To do so, the total (bonded and free) 7-ketocholesterol content was measured in ten fresh human mature milk samples and in ten milk adapted formula samples by high performance liquid chromatography and diode array detection. The 7-ketocholesterol human milk content (0.7+/-0.3) was often below the quantifiable limit (0.5 microg/g of extracted lipids) while 7-ketocholesterol adapted milk concentrations were often above (3.6+/-4.0) this limit. The 7-ketocholesterol content of adapted formula samples was significantly higher as compared to human milk samples (P<0.05). This is the first study to provide data concerning the concentrations of cholesterol oxides in human milk and in formula milk. Our results clearly suggest that the manufacturing technologies employed and the nutrient extractive sources play a crucial role in the development of cholesterol oxides in the end product. Careful surveillance has to be paid in order to avoid alteration of bioactive properties of nutrients and/or development of potentially toxic derivative compounds.


Assuntos
Inibidores Enzimáticos/análise , Alimentos Infantis , Cetocolesteróis/análise , Leite Humano/química , Colesterol/análise , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Recém-Nascido , Lipídeos/análise
7.
Diabetologia ; 45(6): 798-804, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12107723

RESUMO

AIMS/HYPOTHESIS: The pathogenesis of permanent diabetes mellitus diagnosed early in life is heterogeneous and, in most cases, not known. We aimed at identifying markers differentiating between non-autoimmune and autoimmune diabetes. METHODS: The clinical, genetic and epidemiological features of 111 diabetic patients (62 males) who received insulin within 12 months of life were studied. RESULTS: The epidemic curve by age of diabetes onset revealed two subsets of patients at a cutoff of 180 days. In the group with diabetes onset before 180 days ("early onset" permanent diabetes) the analysis of HLA susceptibility heterodimers (available for 21 individuals) showed that 76% had a "protective" HLA genotype for Type I (insulin-dependent) diabetes mellitus as compared to 11.9% (5/42) of the later onset group. Accordingly, "early onset" children were less likely to have autoimmunity markers (4 out of 26 tested) than children with onset after 180 days (13 out 20 tested) (15.4% vs. 65.0%, p<0.01). Of note, 19 out of 20 (or the 95%) patients who were born on the island of Sardinia, an Italian region where the incidence of Type I diabetes is six times higher than continental Italy (33/100,000/year vs 5/100,000/year), were included in the later onset group (>180 days). Small-for-date birthweight, a possible sign of reduced foetal insulin secretion, was more common in the "early onset" group (OR=9.9, 95%-CI 2.6-38.6). CONCLUSION/INTERPRETATION: These results, obtained in the largest population-based cohort of diabetic infants hitherto reported, suggest that "early onset" permanent diabetes cases differ from later onset cases and that most of them do not have an autoimmune pathogenesis.


Assuntos
Idade de Início , Diabetes Mellitus Tipo 1/epidemiologia , Insulina/uso terapêutico , Autoanticorpos/sangue , Peso ao Nascer , Estudos de Coortes , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/imunologia , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Ilhotas Pancreáticas/imunologia , Itália/epidemiologia , Masculino , Fatores de Risco , Estações do Ano
8.
Am J Med Genet ; 104(1): 69-74, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11746031

RESUMO

We describe two newborn brothers with a pattern of malformation characterized by the persistence of Müllerian duct derivatives, intestinal lymphangiectasia, hypertrophied alveolar ridges, and early death. Postmortem examination showed the presence of a rudimentary uterus, fallopian tubes, the upper third of a vagina, a prostate of normal shape, a dilated colon, and generalized intestinal and pulmonary lymphangiectasia. The syndrome was first delineated by Urioste and co-workers [1993: Am J Med Genet 47:494-503]. These cases confirm the existence of a definite and distinct entity.


Assuntos
Anormalidades Múltiplas/genética , Linfangiectasia Intestinal/genética , Ductos Paramesonéfricos/anormalidades , Anormalidades Múltiplas/patologia , Adulto , Evolução Fatal , Feminino , Humanos , Recém-Nascido , Linfangiectasia Intestinal/patologia , Síndrome
9.
Development ; 128(12): 2291-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11493548

RESUMO

In plants, development is a continuing process that takes place under strong fluctuations of the light environment. Here we show that in Arabidopsis thaliana plants grown under intense white light, coupling of the photoreceptor cryptochrome 2 to developmental processes is broader than previously appreciated. Compared to the wild type, the cry2 mutant showed reduced activity of a Lhcb1*2 promoter fused to a reporter, and delayed flowering. The cry2 mutation also reduced the inhibition of hypocotyl growth, the unfolding of the cotyledons, the rate of leaf production during the vegetative phase, and the pace of development after transition to the reproductive stage; but these effects were obvious only in the absence of cryptochrome 1 and in some cases phytochrome A and/or phytochrome B. Complementary, the cry2 mutation uncovered novel roles for cryptochrome 1 and phytochrome A. The activity of the Lhcb1*2 promoter was higher in the cry1 cry2 mutant than in the cry2 mutant, suggesting that cry1 could be involved in blue-light repression of photosynthetic genes. Surprisingly, the phyA cry1 cry2 triple mutant flowered earlier and showed better response to photoperiod than the cry1 cry2 double mutant, indicating that phyA is involved in light repression of flowering. Growth and development were severely impaired in the quadruple phyA phyB cry1 cry2 mutant. We propose that stability and light modulation of development are achieved by simultaneous coupling of phytochrome A, phytochrome B, cryptochrome 1 and cryptochrome 2 to developmental processes, in combination with context-dependent hierarchy of their relative activities.


Assuntos
Proteínas de Drosophila , Proteínas do Olho , Flavoproteínas/fisiologia , Células Fotorreceptoras de Invertebrados , Células Fotorreceptoras , Complexo de Proteínas do Centro de Reação Fotossintética , Fitocromo/fisiologia , Fatores de Transcrição , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis , Cotilédone/fisiologia , Criptocromos , Flavoproteínas/genética , Luz , Fenótipo , Complexo de Proteínas do Centro de Reação Fotossintética/genética , Fitocromo/genética , Fitocromo A , Fitocromo B , Folhas de Planta/fisiologia , Receptores Acoplados a Proteínas G , Fatores de Tempo
10.
Arch Dis Child Fetal Neonatal Ed ; 85(2): F86-90, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11517199

RESUMO

OBJECTIVE: To compare the effectiveness of the Infant Flow Driver (IFD) with single prong nasal continuous positive airway pressure (nCPAP) in preterm neonates affected by respiratory distress syndrome. DESIGN: Randomised controlled study. PATIENTS: Between September 1997 and March 1999, 36 preterm infants who were eligible for CPAP treatment were randomly selected for either nCPAP or IFD and studied prospectively for changes in oxygen requirement and/or respiratory rate. The requirement for mechanical ventilation, complications of treatment, and effects on mid-term outcome were also evaluated. RESULTS: Use of the IFD had a significantly beneficial effect on both oxygen requirement and respiratory rate (p < 0.0001) when compared with nCPAP. Moreover, O(2) requirement and respiratory rate were significantly decreased by four hours (p < 0.001 and p < 0.03 respectively). The probability of remaining supplementary oxygen free over the first 48 hours of treatment was significantly higher in patients treated with the IFD than with nCPAP (p < 0.02). IFD treated patients had a higher success (weaning) rate (94% v 72 %) and shorter duration of treatment (49.3 (31) v 56 (29.7) hours respectively; mean (SD)), although the difference was not significant. CONCLUSIONS: IFD appears to be a feasible device for managing respiratory distress syndrome in preterm infants, and benefits may be had with regard to oxygen requirement and respiratory rate when compared with nCPAP. The trend towards reduced requirement for mechanical ventilation, shorter clinical recovery time, and shorter duration of treatment requires further evaluation in a multicentre randomised clinical trial.


Assuntos
Respiração com Pressão Positiva/instrumentação , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Feminino , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Oxigênio/administração & dosagem , Estudos Prospectivos , Respiração , Síndrome do Desconforto Respiratório do Recém-Nascido/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Desmame do Respirador
11.
Plant Physiol ; 126(2): 780-8, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11402206

RESUMO

Ultraviolet B radiation (UV-B, 290-315 nm) can cause damage and induce photomorphogenic responses in plants. The mechanisms that mediate the photomorphogenic effects of UV-B are unclear. In etiolated Arabidopsis seedlings, a daily exposure to 2.5 h of UV-B enhanced the cotyledon opening response induced by a subsequent red light (R) pulse. An R pulse alone, 2.5 h of UV-B terminated with a far-red pulse, or 2.5 h of continuous R caused very little cotyledon opening. The enhancing effect of UV-B increased with fluence rate up to approximately 7.58 micromol m(-2) s(-1); at higher fluence rates the response to UV-B was greatly reduced. The phyA, phyA cry1, and cry1 cry2 mutants behaved like the wild type when exposed to UV-B followed by an R pulse. In contrast, phyB, phyB cry1, and phyB phyA mutants failed to open the cotyledons. Thus, phytochrome B was required for the cotyledon opening response to UV-B --> R treatments, whereas phytochrome A and cryptochromes 1 and 2 were not necessary under the conditions of our experiments. The enhancing effect of low doses of UV-B on cotyledon opening in uvr1 uvr2 and uvr1 uvr3 mutants, deficient in DNA repair, was similar to that found in the wild type, suggesting that this effect of UV-B was not elicited by signals derived from UV-B-induced DNA lesions (cyclobutane pyrimidine dimers and 6-4 photoproducts). We conclude that low doses of UV-B, perceived by a receptor system different from phytochromes, cryptochromes, or DNA, enhance a de-etiolation response that is induced by active phytochrome B.


Assuntos
Arabidopsis/efeitos da radiação , Células Fotorreceptoras , Fitocromo/metabolismo , Fatores de Transcrição , Raios Ultravioleta , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Proteínas de Arabidopsis , Cotilédone/efeitos da radiação , Morfogênese , Fitocromo B
13.
Nat Genet ; 27(1): 18-20, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11137992

RESUMO

To determine whether human X-linked neonatal diabetes mellitus, enteropathy and endocrinopathy syndrome (IPEX; MIM 304930) is the genetic equivalent of the scurfy (sf) mouse, we sequenced the human ortholog (FOXP3) of the gene mutated in scurfy mice (Foxp3), in IPEX patients. We found four non-polymorphic mutations. Each mutation affects the forkhead/winged-helix domain of the scurfin protein, indicating that the mutations may disrupt critical DNA interactions.


Assuntos
Doenças dos Animais/genética , Proteínas de Ligação a DNA/genética , Diabetes Mellitus/congênito , Diabetes Mellitus/genética , Poliendocrinopatias Autoimunes/genética , Enteropatias Perdedoras de Proteínas/genética , Cromossomo X/genética , Sequência de Aminoácidos , Animais , Análise Mutacional de DNA , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Fatores de Transcrição Forkhead , Ligação Genética/genética , Humanos , Recém-Nascido , Camundongos , Camundongos Mutantes , Dados de Sequência Molecular , Mutação/genética , Alinhamento de Sequência , Síndrome
14.
J Biol Rhythms ; 16(6): 523-30, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11760010

RESUMO

The authors sought to investigate the role of phytochromes A and B (phyA and phyB) and cryptochromes 1 and 2 (cryl and cry2) in the synchronization of the leaf position rhythm in Arabidopsis thaliana. The seedlings were transferred from white light-dark cycles to free-running conditions with or without exposure to a light treatment during the final hours of the last dark period. The phase advance caused by a far-red light treatment was absent in the phyA mutant, deficient in the fhy1 and fhy3 mutants involved in phyA signaling, and normal in the cryl and cryl cry2 mutants. The phase shift caused by blue light was normal in the cry2 mutant; reduced in the phyA, cryl, phyA cry1, and cry1 cry2 mutants; and abolished in the phyA cryl cry2 triple mutant. The phase shift caused by red light was partially retained by the phyA phyB double mutant. The authors conclude that cryl and cry2 participate as photoreceptors in the blue light input to the clock but are not required for the phyA-mediated effects on the phase of the circadian rhythm of leaf position. The signaling proteins FHY1 and FHY3 are shared by phyA-mediated photomorphogenesis and phyA input to the clock.


Assuntos
Arabidopsis/fisiologia , Ritmo Circadiano/fisiologia , Proteínas de Drosophila , Proteínas do Olho , Flavoproteínas/fisiologia , Células Fotorreceptoras de Invertebrados , Células Fotorreceptoras , Fitocromo/fisiologia , Fatores de Transcrição , Arabidopsis/anatomia & histologia , Arabidopsis/genética , Proteínas de Arabidopsis , Ritmo Circadiano/genética , Cor , Criptocromos , Flavoproteínas/genética , Luz , Mutação/genética , Fitocromo/genética , Fitocromo A , Fitocromo B , Pigmentação , Receptores Acoplados a Proteínas G , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
15.
Curr Biol ; 10(16): 1013-5, 2000 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-10985392

RESUMO

Time measurement and light detection are inextricably linked. Cryptochromes, the blue-light photoreceptors shared between plants and animals, are critical for circadian rhythms in flies and mice [1-3]. WC-1, a putative blue-light photoreceptor, is also essential for the maintenance of circadian rhythms in Neurospora [4]. In contrast, we report here that in Arabidopsis thaliana the double mutant lacking the cryptochromes cry1 and cry2, and even a quadruple mutant lacking the red/ far-red photoreceptor phytochromes phyA and phyB as well as cry1 and cry2, retain robust circadian rhythmicity. Interestingly, the quadruple mutant was nearly blind for developmental responses but perceived a light cue for entraining the circadian clock. These results indicate that cryptochromes and phytochromes are not essential components of the central oscillator in Arabidopsis and suggest that plants could possess specific photosensory mechanisms for temporal orientation, in addition to cryptochromes and phytochromes, which are used for both spatial and temporal adaptation.


Assuntos
Arabidopsis/genética , Arabidopsis/fisiologia , Ritmo Circadiano , Proteínas de Drosophila , Proteínas do Olho , Mutação , Células Fotorreceptoras de Invertebrados , Células Fotorreceptoras , Complexo de Proteínas do Centro de Reação Fotossintética/genética , Fatores de Transcrição , Proteínas de Arabidopsis , Criptocromos , Flavoproteínas/genética , Flavoproteínas/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Fitocromo/genética , Fitocromo/metabolismo , Fitocromo A , Fitocromo B , Receptores Acoplados a Proteínas G
16.
Planta ; 210(3): 497-501, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10750908

RESUMO

Vegetative plants of Arabidopsis thaliana (L.) Heynh. form a compact rosette of leaves in which internode growth is virtually arrested. Rapid extension of the internodes occurs after flower buds are present in the reproductive apex. Under natural radiation, continuous light from fluorescent lamps, or short photoperiods of light from fluorescent lamps, plants of the phyB cry1 double mutant (lacking both phytochrome B and cryptochrome 1) did not form normal rosettes because all the internodes showed some degree of elongation. Internode elongation was weak in thephyB single mutant and absent in the cry1 mutant, indicating redundancy between phytochrome B and cryptochrome 1. The absence of phytochrome A caused no effects. The failure to form normal rosettes was conditional because internode elongation was arrested at low temperatures in all the mutant combinations. In contrast, the temperature dependence of phytochrome B and cryptochrome 1 effects on hypocotyl growth was weak. The elongation of the internodes in phyB cry1 was not accompanied by early flowering as showed by the lack of effects on the final number of leaves. Apex dissection indicated that in phyB cry1 double mutants internode elongation anticipated the transition from the vegetative to the reproductive stage. Thus, stem growth in Arabidopsis thaliana is not fully dependent on the program of reproductive development.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Proteínas de Drosophila , Proteínas do Olho , Flavoproteínas/fisiologia , Células Fotorreceptoras de Invertebrados , Células Fotorreceptoras , Fitocromo/fisiologia , Fatores de Transcrição , Proteínas de Arabidopsis , Relógios Biológicos , Criptocromos , Flavoproteínas/genética , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Fitocromo/genética , Fitocromo B , Receptores Acoplados a Proteínas G , Temperatura
17.
Acta Biomed Ateneo Parmense ; 71 Suppl 1: 621-6, 2000.
Artigo em Italiano | MEDLINE | ID: mdl-11424817

RESUMO

BACKGROUND: It has been largely shown that during the first month of life, in the preterm neonate Hb levels and Hct percentages rapidly decrease, high HbF concentration persists and a high oxygen affinity occurs. Data are needed to establish the level at which 2,3 dyphosphoglycerate (2,3 DPG) interacts with the regulation of oxygen affinity. SUBJECTS AND METHODS: 24 samples, from eight uncomplicated preterm newborns (34.1 +/- 1.83 GW, 1869 +/- +/- 291 BW) obtained at the same time as those required for the clinical management of the infants, were collected on the 2nd, 7th and 14th day of life. Blood gases, total hemoglobin and hematocrit were obtained from 0.3 ml arterialised capillary blood. Assays of 2,3 DPG were made separately on 0.4 ml venous blood. RESULTS: As expected tHb concentration and Hct percentages significantly decreased from day 2 to day 14 in all eight cases. On the contrary 2,3 DPG and p50 values remained stable. Subsequently throughout the study period all neonates had an increased 2,3 DPG/Hb ratio that was significantly related with p50 at standard conditions (p < 0.05). CONCLUSIONS: Stable 2,3 DPG concentrations during all study period have been detected. The subsequent significant increased 2.3 DPG/Hb, ratio related to increased p50 values, could have a key role in a physiological mechanism aimed to ensure adequate oxygen delivery to the tissues and to counteract the higher oxygen affinity of fetal hemoglobin. A wider sample is needed to validate this hypothesis.


Assuntos
2,3-Difosfoglicerato/sangue , Recém-Nascido Prematuro/sangue , Humanos , Recém-Nascido
18.
Acta Biomed Ateneo Parmense ; 71 Suppl 1: 657-61, 2000.
Artigo em Italiano | MEDLINE | ID: mdl-11424824

RESUMO

A computer software package was developed to perform the calculation involved in compounding total and partial parenteral nutrition for low-birth-weight and sick newborns. The program requires a minimum of user input and is menu-driven. The flexibility of the algorithm has been increased to a considerable degree. The program calculates the overall balance of fluids, nutrients, calories, electrolytes and minerals. It allows for the possibility of total parenteral nutrition and simultaneous oral feeding. Nutrient amounts per Kg per day and combination of enteral food and parenteral infusions can be completely changed by the operator. In our experience computer-assisted system was more efficient than a manual system and the possibility of computational error was reduced.


Assuntos
Terapia Intensiva Neonatal , Nutrição Parenteral , Soluções Farmacêuticas , Software , Terapia Assistida por Computador , Humanos , Recém-Nascido
19.
Plant Physiol ; 118(1): 19-25, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9733522

RESUMO

Wild-type or phyA, phyB, or hy4 mutant Arabidopsis seedlings lacking phytochrome A (phyA), phytochrome B (phyB), or cryptochrome 1 (cry1), respectively, and the double and triple mutants were used in combination with blue-light treatments given simultaneously with red or far-red light. We investigated the interaction between phytochromes and cry1 in the control of hypocotyl growth and cotyledon unfolding. Under conditions deficient for cry1 (short exposures to blue light) or phyB (far-red background), these photoreceptors acted synergistically: Under short exposures to blue light (3 h/d) added to a red-light background, cry1 activity required phyB (e.g. the hy4 mutant was taller than the wild type but the phyBhy4 mutant was not taller than the phyB mutant). Under prolonged exposures to blue light (24 h/d) added to a far-red light background, phyB activity required cry1 (e.g. the phyAphyB mutant was taller than the phyA mutant but the phyAphyBhy4 mutant was not taller than the phyAhy4 mutant). Under more favorable light inputs, i.e. prolonged exposures to blue light added to a red-light background, the effects of cry1 and phyB were independent. Thus, the synergism between phyB and cry1 is conditional. The effect of cry1 was not reduced by the phyA mutation under any tested light condition. Under continuous blue light the triple mutant phyAphyBhy4 showed reduced hypocotyl growth inhibition and cotyledon unfolding compared with the phyAphyB mutant. The action of cry1 in the phyAphyB double mutant was higher under the red-light than the far-red-light background, indicating a synergistic interaction between cry1 and phytochromes C, D, or E; however, a residual action of cry1 independent of any phytochrome is likely to occur.


Assuntos
Arabidopsis/genética , Proteínas de Drosophila , Proteínas do Olho , Flavoproteínas/genética , Genes de Plantas , Células Fotorreceptoras de Invertebrados , Células Fotorreceptoras , Fitocromo/genética , Proteínas de Plantas/genética , Fatores de Transcrição , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis , Criptocromos , Flavoproteínas/fisiologia , Luz , Mutação , Fenótipo , Fitocromo/fisiologia , Fitocromo A , Fitocromo B , Proteínas de Plantas/fisiologia , Receptores Acoplados a Proteínas G
20.
Acta Paediatr ; 86(3): 326-9, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9099328

RESUMO

We report a newborn admitted to our service on the 2nd day of life because of hypotonia and metabolic acidosis. A progressive hepatocellular dysfunction dominated the clinical picture and the patient died at 13 months of age because of severe hepatic failure. Persistent lactic acidosis, high ketone bodies levels and high-normal lactate/pyruvate and 3-hydroxybutyrate/acetoacetate molar ratios in plasma were found. Investigation of a liver biopsy revealed low activities of all the mitochondrial respiratory chain enzymes but in particular a marked decrease of complex I (NADH cytochrome c reductase) activity. All respiratory chain enzyme activities were normal in cultured skin fibroblasts. Mitochondrial DNA analysis failed to detect any major rearrangements. Although only a few cases have been reported so far, it is becoming clear that liver should be considered as one of the organs involved in oxidative phosphorylation disorders. The finding of unexplained progressive liver failure with poor neurological conditions, lactic acidaemia and ketonuria strongly warrants investigation for a respiratory chain disorder. Moreover, the finding of normal respiratory enzyme activities in a tissue other than liver does not rule out the existence of an oxidative phosphorylation disorder in patients with hepatocellular disease of unexplained origin.


Assuntos
Acidose Láctica/complicações , Falência Hepática/complicações , NADPH-Ferri-Hemoproteína Redutase/deficiência , Acidose Láctica/diagnóstico , Eletroencefalografia , Transporte de Elétrons , Evolução Fatal , Feminino , Humanos , Recém-Nascido , Falência Hepática/diagnóstico , Fosforilação Oxidativa , Ultrassonografia
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