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1.
J Neurosci Res ; 100(8): 1585-1601, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35014067

RESUMO

Ethanol exposure during the early stages of embryonic development can lead to a range of morphological and behavioral differences termed fetal alcohol spectrum disorders (FASDs). In a zebrafish model, we have shown that acute ethanol exposure at 8-10 hr postfertilization (hpf), a critical time of development, produces birth defects similar to those clinically characterized in FASD. Dysregulation of the Sonic hedgehog (Shh) pathway has been implicated as a molecular basis for many of the birth defects caused by prenatal alcohol exposure. We observed in zebrafish embryos that shh expression was significantly decreased by ethanol exposure at 8-10 hpf, while smo expression was much less affected. Treatment of zebrafish embryos with SAG or purmorphamine, small molecule Smoothened agonists that activate Shh signaling, ameliorated the severity of ethanol-induced developmental malformations including altered eye size and midline brain development. Furthermore, this rescue effect of Smo activation was dose dependent and occurred primarily when treatment was given after ethanol exposure. Markers of Shh signaling (gli1/2) and eye development (pax6a) were restored in embryos treated with SAG post-ethanol exposure. Since embryonic ethanol exposure has been shown to produce later-life neurobehavioral impairments, juvenile zebrafish were examined in the novel tank diving test. Our results further demonstrated that in zebrafish embryos exposed to ethanol, SAG treatment was able to mitigate long-term neurodevelopmental impairments related to anxiety and risk-taking behavior. Our results indicate that pharmacological activation of the Shh pathway at specific developmental timing markedly diminishes the severity of alcohol-induced birth defects.


Assuntos
Transtornos do Espectro Alcoólico Fetal , Efeitos Tardios da Exposição Pré-Natal , Animais , Embrião não Mamífero/metabolismo , Etanol/toxicidade , Feminino , Transtornos do Espectro Alcoólico Fetal/tratamento farmacológico , Transtornos do Espectro Alcoólico Fetal/metabolismo , Proteínas Hedgehog/metabolismo , Humanos , Gravidez , Peixe-Zebra/metabolismo
2.
J Dairy Sci ; 103(10): 9548-9560, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32828498

RESUMO

The objectives were to study the effect of 2 different premilking stimulation regimens, with and without manual forestripping, on teat tissue condition and milking characteristics in dairy cows. In a randomized controlled crossover study, 130 Holstein cows milked 3 times daily were assigned to treatment and control groups. Premilking udder preparation for the treatment group consisted of: (1) predipping with 1% iodine, (2) sequential forestripping of 3 streams of milk per quarter, (3) wiping of teats, and (4) attachment of the milking unit. Premilking udder preparation for the control group was identical except that the forestripping step was omitted. The mean tactile stimulation durations were 16 s and 7 s for the treatment and control group, respectively. The time spent from first tactile stimulus (either forestripping or wiping of teats) to milking unit attachment was kept consistent at 90 s for both groups. The study lasted for 14 d with 2 periods, each consisting of a 2-d adjustment time followed by 5 d of data collection. Machine milking-induced short-term changes to the teat tissue were assessed by palpation and visually. The following milking characteristics were assessed with electronic on-farm milk meters: milk yield (MY), milking unit-on time (MUOT), 2-min MY (2MIN), and time spent in low milk flow rate (LMF). Generalized linear mixed models were used to describe the effect of treatment on the outcome variables. The odds of machine milking-induced short-term changes to the teat tissue were lower for cows that received forestripping compared with cows that were not forestripped (odds ratio = 0.31; 95% confidence interval = 0.22-0.42). Least squares means (95% confidence interval) for cows that were forestripped and animals that were not forestripped, respectively, were 12.7 (12.2-13.2) and 12.7 (12.2-13.2) kg for MY and 6.1 (5.8-6.4) and 5.6 (5.3-5.9) kg for 2MIN. There was an interaction between treatment and MY for LMF. Time spent in LMF for cows that were forestripped and received no forestripping, respectively, were 18 (17-20) and 24 (23-26) s for a MY level of 10 kg; and 13 (12-14) and 15 (14-16) s for a MY level of 15 kg. The effect of treatment on MUOT was modified by parity. Milking unit-on times for animals in first, second and third or greater lactation, respectively, were 230 (219-243), 249 (236-262), and 260 (249-272) s for cows that were forestripped, and 245 (232-258), 252 (239-266), and 268 (257-281) s for cows that received no forestripping. In this study, cows that were forestripped had shorter MUOT, higher 2MIN, lower LMF, and lower odds of exhibiting changes to the teat tissue after machine milking. We conclude that wiping of teats during premilking udder preparation alone and omitting forestripping of teats without compensating for the loss in stimulation time may not provide sufficient tactile stimulation to elicit the cows' maximum physiological milk-ejection capacity. This can aggravate the adverse effects of vacuum-induced forces on teat tissue during machine milking, diminish animal well-being, and possibly affect udder health.


Assuntos
Bovinos/fisiologia , Indústria de Laticínios/métodos , Glândulas Mamárias Animais/fisiologia , Leite/metabolismo , Animais , Estudos Cross-Over , Feminino , Modelos Lineares , Distribuição Aleatória
3.
Rev Mal Respir ; 35(3): 328-332, 2018 Mar.
Artigo em Francês | MEDLINE | ID: mdl-29580615

RESUMO

INTRODUCTION: Different clinico-biological parameters are used to estimate the amount of oxygen available for the organism. Oxygen saturation measured with pulse oxymetry (SpO2), oxygen saturation of arterial blood (SaO2) and oxygen partial pressure of the arterial blood (PaO2) are the most commonly used. CASE REPORT: We report the case of a patient admitted for investigation of respiratory failure in the context of chronic dyspnea of effort. SpO2 and SaO2 were decreased, though the PaO2 was normal. This mismatch between oxygen saturation and PaO2 led to the diagnosis of hemoglobinopathy (Bassett hemoglobin). CONCLUSION: The diagnosis of hemoglobinopathy should be considered in cases of oxygen desaturation with normal respiratory and cardiac investigations. There are no reasons to prescribe long-term oxygen to these patients.


Assuntos
Gasometria/métodos , Hemoglobinopatias/diagnóstico , Oximetria , Oxigênio/sangue , Insuficiência Respiratória/diagnóstico , Adulto , Gasometria/normas , Diagnóstico Diferencial , Feminino , Hemoglobinopatias/sangue , Hemoglobinopatias/complicações , Humanos , Oxigênio/análise , Insuficiência Respiratória/sangue , Insuficiência Respiratória/etiologia
4.
Gene Ther ; 22(5): 357-64, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25630949

RESUMO

Lentiviral vectors have proved an effective method to deliver transgenes into the brain; however, they are often hampered by a lack of spread from the site of injection. Modifying the viral envelope with a portion of a rabies envelope glycoprotein can enhance spread in the brain by using long-range axon projections to facilitate retrograde transport. In this study, we generated two chimeric envelopes containing the extra-virion and transmembrane domain of rabies SADB19 or CVS-N2c with the intra-virion domain of vesicular stomatitis virus. Viral particles were packaged containing a green fluorescent protein reporter construct under the control of the phosphoglycerokinase promoter. Both vectors produced high-titer particles with successful integration of the glycoproteins into the particle envelope and significant transduction of neurons in vitro. Injection of the SADB19 chimeric viral vector into the lumbar spinal cord of adult mice mediated a strong preference for gene transfer to local neurons and axonal terminals, with retrograde transport to neurons in the brainstem, hypothalamus and cerebral cortex. Development of this vector provides a useful means to reliably target select populations of neurons by retrograde targeting.


Assuntos
Transporte Axonal , Técnicas de Transferência de Genes , Lentivirus/genética , Vírus da Raiva/genética , Medula Espinal/citologia , Vesiculovirus/genética , Proteínas do Envelope Viral/genética , Animais , Células Cultivadas , Vetores Genéticos/genética , Glicerol Quinase/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Regiões Promotoras Genéticas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Medula Espinal/metabolismo , Proteínas do Envelope Viral/metabolismo
5.
Br J Cancer ; 110(4): 976-83, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24366298

RESUMO

BACKGROUND: Securing a diagnosis of ovarian cancer and establishing means to predict outcomes to therapeutics remain formidable clinical challenges. Early diagnosis is particularly important since survival rates are markedly improved if tumour is detected early. METHODS: Comprehensive miRNA profiles were generated on presurgical plasma samples from 42 women with confirmed serous epithelial ovarian cancer, 36 women diagnosed with a benign neoplasm, and 23 comparably age-matched women with no known pelvic mass. RESULTS: Twenty-two miRNAs were differentially expressed between healthy controls and the ovarian cancer group (P<0.05), while a six miRNA profile subset distinguished presurgical plasma from benign and ovarian cancer patients. There were also significant differences in miRNA profiles in presurgical plasma from women diagnosed with ovarian cancer who had short overall survival when compared to women with long overall survival (P<0.05). CONCLUSION: Our preliminary data support the utility of circulating plasma miRNAs to distinguish women with ovarian cancer from those with a benign mass and identify women likely to benefit from currently available treatment for serous epithelial ovarian cancer from those who may not.


Assuntos
Biomarcadores Tumorais/sangue , MicroRNAs/sangue , Neoplasias Epiteliais e Glandulares/sangue , Neoplasias Epiteliais e Glandulares/mortalidade , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma Epitelial do Ovário , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , Sobrevida , Resultado do Tratamento , Adulto Jovem
6.
Curr Med Chem ; 18(21): 3136-55, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21671856

RESUMO

Cancer remains one of the major causes of death worldwide. The switch to pathological angiogenesis is a key process in the promotion of cancer and consequently provides several new and promising targets to anticancer therapy. Thus, antagonizing angiogenesis cuts off the tumor's oxygen and nutrition supply. This review focuses on angiogenesis inhibitors as option for cancer treatment. Modes of action, adverse effects, mechanisms of resistance as well as new developments are highlighted. One approach in angiogenesis inhibition is intermitting the further VEGF (vascular endothelial growth factor) signal pathway with monoclonal antibodies. Bevacizumab is a highly specific recombinant humanized monoclonal IgG antibody targeting VEGF-A. An efficient antitumor therapy demands more specific antibodies that affect other signal molecules besides VEGF-A, which is in the focus of current research. In addition to antagonizing VEGF, there are also small molecules that inhibit receptor tyrosine kinases (RTKs). Many RTK inhibitors have been described, which exhibit different specificity profiles. The question, whether highly specific antagonists are necessary remains open, because other affected RTKs may also represent growth factor receptors that are essential for tumor growth. Therefore their inhibition may also contribute to anticancer activity. Secondary plant metabolites represent templates for the development of new small molecules. The identification of new drugs from plants has a long and successful history. There is convincing evidence for the beneficial effect of phytochemicals on cancer-related pathways, particularly with regard to anti-angiogenesis. Plant phenolics are the most important category of phytochemicals, including flavanoids. Prominent phytochemicals affecting different pathways of angiogenesis are green tea polyphenols (epigallocatechin gallate) and soy bean isoflavones (genistein).


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Produtos Biológicos/uso terapêutico , Neoplasias/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Bibliotecas de Moléculas Pequenas/uso terapêutico , Inibidores da Angiogênese/farmacologia , Animais , Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Produtos Biológicos/farmacologia , Humanos , Neoplasias/irrigação sanguínea , Bibliotecas de Moléculas Pequenas/farmacologia , Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores
7.
J Oral Rehabil ; 36(11): 848-55, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19793231

RESUMO

The aim of this investigation was to determine colour compatibility between dental shade guides, namely, VITA Classical (VC) and VITA 3D-Master (3D), and human teeth in quinquagenarians and septuagenarians. Tooth colour, described in terms of L*a*b* values of the middle third of facial tooth surface of 1391 teeth, was measured using VITA Easyshade in 195 subjects (48% female). These were compared with the colours (L*a*b* values) of the shade tabs of VC and 3D. The mean coverage error and the percentage of tooth colours being within a given colour difference (DeltaE(ab)) from the tabs of VC and 3D were calculated. For comparison, hypothetical, optimized, population-specific shade guides were additionally calculated based on discrete optimization techniques for optimizing coverage. Mean coverage error was DeltaE(ab) = 3.51 for VC and DeltaE(ab) = 2.96 for 3D. Coverage of tooth colours by the tabs of VC and 3D within DeltaE(ab) = 2 was 23% and 24%, respectively, (DeltaE(ab)

Assuntos
Planejamento de Prótese Dentária/instrumentação , Pigmentação em Prótese/instrumentação , Idoso , Algoritmos , Cor , Estética Dentária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Referência , Espectrofotometria , Dente/anatomia & histologia
8.
J Pharm Sci ; 98(1): 146-58, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18393299

RESUMO

Ranitidine hydrochloride (RAN-HCl), a known anti-ulcer drug, is the product of reaction between HCl and ranitidine base (RAN-B). RAN-HCl has been extensively studied; however this is not the case of the RAN-B. The solid state characterization of RAN-B polymorphs has been carried out using different analytical techniques (microscopy, thermal analysis, Fourier transform infrared spectrometry in the attenuated total reflection mode, (13)C-CPMAS-NMR spectroscopy and X-ray powder diffraction). The crystal structures of RAN-B form I and form II have been determined using conventional X-ray powder diffraction in combination with simulated annealing and whole profile pattern matching, and refined using rigid-body Rietveld refinement. RAN-B form I is a monoclinic polymorph with cell parameters: a = 7.317(2), b = 9.021(2), c = 25.098(6) A, beta = 95.690(1) degrees and space group P2(1)/c. The form II is orthorhombic: a = 31.252(4), b = 13.052(2), c = 8.0892(11) A with space group Pbca. In RAN-B polymorphs, the nitro group is involved in a strong intramolecular hydrogen bond responsible for the existence of a Z configuration in the enamine portion of the molecules. A tail to tail packing motif can be denoted via intermolecular hydrogen bonds. The crystal structures of RAN-B forms are compared to those of RAN-HCl polymorphs. RAN-B polymorphs are monotropic polymorphic pairs.


Assuntos
Pós/química , Ranitidina/química , Difração de Raios X/métodos , Cristalização/métodos , Pós/análise , Ranitidina/análise , Estereoisomerismo
9.
Acta Radiol ; 49(3): 337-43, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18365824

RESUMO

BACKGROUND: Some side effects of intravenously injected iodinated contrast media are thought to be linked to the biological properties of the various agents and their effect on blood components. PURPOSE: To assess the effect of osmolarity and injection temperature of iodinated contrast media on erythrocyte (RBC) morphology in vitro. MATERIAL AND METHODS: Blood from 20 volunteers was incubated with three different contrast media (320 mg I/ml iso-osmolar iodixanol, 300 mg I/ml low-osmolar iopromide, 300 mg I/ml low-osmolar iopamidol) injected at 37 degrees C, 43 degrees C, and 48 degrees C, and in two different volumes corresponding to the estimated concentration at the site of venous injection and after systemic distribution. After 10 min incubation, aliquots were removed for complete blood count analysis and blood smears. Two hematologists blindedly and independently reviewed all smears, and determined the grade of morphological RBC changes compared to a blank sample. RESULTS: There was excellent (kappa = 0.98) inter-reader correlation for grading RBC changes. At systemic concentration at 37 degrees C, the grade of RBC changes was significantly (P<0.05) less in blood samples exposed to iso-osmolar iodixanol (mean 0.21) as compared to low-osmolar iopromide (mean 0.26) and low-osmolar iopamidol (mean 0.58). These differences became more significant at higher volumes, corresponding to concentrations at the site of injection and higher injection temperatures. CONCLUSION: In vitro, RBC morphology is less affected by iso-osmolar as compared to low-osmolar contrast media. These differences become more significant at higher injection temperatures that are proposed to improve flow dynamics for high-speed injection.


Assuntos
Meios de Contraste/farmacologia , Eritrócitos/efeitos dos fármacos , Iohexol/análogos & derivados , Iopamidol/farmacologia , Temperatura , Ácidos Tri-Iodobenzoicos/farmacologia , Adulto , Células Cultivadas , Feminino , Humanos , Iohexol/farmacologia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Concentração Osmolar , Valores de Referência
10.
Can J Zool ; 86(10): 1085-1094, 2008 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21379405

RESUMO

Behavioral management of risk, in which organisms must balance the requirements of obtaining food resources with the risk of predation, has been of considerable interest to ethologists for many years. Although numerous experiments have shown that animals alter their foraging behavior depending on the levels of perceived risk and demand for nutrients, few have considered the role of genetic variation in the trade-off between these variables. We performed a study of four zebrafish (Danio rerio (Hamilton, 1822)) strains to test for genetic variation in foraging behavior and whether this variation affected their response to both aversive stimuli and nutrient restriction. Zebrafish strains differed significantly in their latency to begin foraging from the surface of the water under standard laboratory conditions. Fish fed sooner when nutrients were restricted, although this was only significant in the absence of aversive stimuli. Aversive stimuli caused fish to delay feeding in a strain-specific manner. Strains varied in food intake and specific growth rate, and feeding latency was significantly correlated with food intake. Our results indicate significant genetic variation in foraging behavior and the perception of risk in zebrafish, with a pattern of strain variation consistent with behavioral adaptation to captivity.

11.
Med J Aust ; 187(5): 271-3, 2007 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-17767430

RESUMO

OBJECTIVE: To determine the live birth rate following surgical reversal of sterilisation in women aged 40 years and older. DESIGN: Retrospective cohort study of pregnancy outcome following day surgery microsurgical reversal of sterilisation performed by two reproductive microsurgeons in the private sector. SETTING AND PATIENTS: 47 patients (aged 40 years or older) who had reversal of sterilisation performed between 1997 and 2005 in Adelaide, South Australia (n=35), or the Infertility Centre of St Louis, Missouri, USA (n=12). MAIN OUTCOME MEASURES: Independently audited live birth surviving the neonatal period. RESULTS: Of the 47 patients on whom follow-up was obtainable from the two centres, 19 (40%) had a live birth, 7 had had only a first trimester miscarriage at the time of follow-up, and 21 (44%) had failed to conceive. Age at conception ranged between 40 and 47 years. Two women had two live births following surgery. The total direct costs (Australian dollars, adjusted to 2005) in Australia were $4850 per treatment, and $11,317 per live birth. The corresponding direct cost of a single cycle of in-vitro fertilisation (IVF) in Australia has been estimated at $6940, with a cost per live birth of $97 884 for women aged 40-42 years and $182,794 for older women. CONCLUSION: Previously sterilised women wanting further pregnancy should be offered tubal surgery as an alternative to IVF, as it offers them the opportunity to have an entirely natural pregnancy. In settings where IVF is financially supported by government agencies or insurance, tubal reversal is a highly cost-effective strategy for the previously fertile woman.


Assuntos
Procedimentos Cirúrgicos Ambulatórios , Coeficiente de Natalidade , Reversão da Esterilização , Adulto , Fatores Etários , Análise Custo-Benefício , Feminino , Fertilização in vitro/economia , Humanos , Pessoa de Meia-Idade , Missouri , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Austrália do Sul , Reversão da Esterilização/economia , Reversão da Esterilização/métodos
12.
J Pharm Sci ; 96(5): 1114-30, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17455340

RESUMO

A new polymorphic form of Alprazolam (Xanax), 8-chloro-1-methyl-6-phenyl-4H-[1,2,4]triazolo-[4,3-alpha][1,4]benzodiazepine, C(17)H(13)ClN(4), has been investigated by means of X-ray powder diffraction (XRPD), single crystal X-ray diffraction, and differential scanning calorimetry (DSC). This polymorphic form (form III) was obtained during DSC experiments after the exothermic recrystallization of the melt of form I. The crystal unit cell dimensions for form III were determined from diffractometer methods. The monoclinic unit cell found for this polymorph using XRPD after indexing the powder diffractogram was confirmed by the cell parameters obtained from single crystal X-ray diffractometry on a crystal isolated from the DSC pans. The single crystal unit cell parameters are: a = 28.929(9), b = 13.844(8), c = 7.361(3) angstroms, beta = 92.82(3) degrees , V = 2944(2) angstroms(3), Z = 8, space group P2(1) (No.4), Dx = 1.393 Mg/m(3). The structure obtained from single crystal X-ray diffraction was used as initial model for Rietveld refinement on the powder diffraction data of form III. The temperature phase transformations of alprazolam were also studied using high temperature XRPD. A review of the different phases available in the Powder Diffraction File (PDF) database for this drug is described bringing some clarification and corrections.


Assuntos
Alprazolam/química , Ansiolíticos/química , Varredura Diferencial de Calorimetria , Cristalização , Cristalografia por Raios X , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Transição de Fase , Difração de Pó , Tecnologia Farmacêutica/métodos , Temperatura , Água/química
13.
J Pharm Sci ; 95(10): 2123-36, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16892212

RESUMO

The crystal structure of carnidazole form II, O-methyl [2-(2-methyl-5-nitro-1H-imidazole-1-yl)ethyl]thiocarbamate, has been determined using synchrotron X-ray powder diffraction in combination with simulated annealing and whole profile pattern matching, and refined by the Rietveld method. For structure solution, 12 degrees of freedom were defined: one motion group and six torsions. Form II crystallizes in space group P2(1)/n, Z=4, with unit cell parameters after Rietveld refinement: a=13.915(4), b=8.095(2), c=10.649(3) A, beta=110.83(1) degrees, and V=1121.1(5) A3. The two polymorphic forms, as well as the hydrate, crystallize in the monoclinic space group P2(1)/n having four molecules in the cell. In form II, the molecules are held together by forming two infinite zig-zag chains via hydrogen bonds of the type N--H...N, the same pattern as in form I. A conformational study of carnidazole, at semiempirical PM3 level, was performed using stochastic approaches based on modification of the flexible torsion angles. The values of the torsion angles for the molecules of the two polymorphic forms and the hydrate of carnidazole are compared to those obtained from the conformational search. Form I and form II are enantiotropic polymorphic pairs this agrees with the fact that the two forms are conformational polymorphs.


Assuntos
Nitroimidazóis/química , Varredura Diferencial de Calorimetria , Cristalização , Modelos Moleculares , Conformação Molecular , Síncrotrons , Água/química , Difração de Raios X/métodos
14.
Rofo ; 178(2): 214-20, 2006 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-16435253

RESUMO

PURPOSE: Intravascular optical coherence tomography (OCT) is a new technique based on infrared light that visualizes the arteries with a resolution of 10-20 microm. Intravascular ultrasound (IVUS) is the current in vivo reference standard and provides a resolution of 100-150 microm. This study compared OCT to IVUS and histopathology with respect to the ability to differentiate atherosclerotic plaques and quantify vascular dimensions in peripheral crural arteries ex vivo. MATERIALS AND METHODS: 50 segments of atherosclerotic arteries derived from five amputated human lower extremities were examined. The different plaque types (fibrous, high-lipid content, calcified) were assigned by two independent examiners, and the sensitivity and specificity of OCT in comparison with histopathology as well as intra- and interobserver consensus were calculated. A comparison of OCT with IVUS addressed the parameters: luminal area (LA), vascular wall area (VA) and plaque area (PA). RESULTS: When comparing OCT and histopathology with respect to the differentiation of various plaque types, sensitivities of 81 % and specificities of 89 % for fibrous plaques, of 100 % and 93 % for lipid-rich plaques and of 80 % and 89 % for calcified plaques were achieved (overall correlation 83 %). Intra- and interobserver consensus was very high (kappa = 0.86 and kappa = 0.89, p < 0.001, respectively). There was also a high correlation between quantitative measurements (Bland-Altman plot [LA]: mean bias, 0.1 mm(2) accuracy +/- 1.8 mm(2), r = 0.95 [p < 0.001] Bland-Altman plot [VA]: mean bias, 0.3 mm(2) accuracy +/- 2.3 mm(2), r = 0.94 [p < 0.001] Bland-Altman plot [PA]: mean bias, 0.4 mm(2) accuracy +/- 2.3 mm(2), r = 0.80 [p < 0.01]. CONCLUSION: OCT allows the differentiation of atherosclerotic plaque types in crural arteries with high accuracy compared to histopathology. Quantitative measurements show a high correlation with IVUS, the current reference standard.


Assuntos
Aterosclerose/classificação , Aterosclerose/patologia , Tomografia de Coerência Óptica/métodos , Diagnóstico Diferencial , Feminino , Humanos , Técnicas In Vitro , Perna (Membro)/irrigação sanguínea , Perna (Membro)/patologia , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença
15.
Eur J Paediatr Neurol ; 5 Suppl A: 135-42, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11588985

RESUMO

The neuronal ceroid lipofuscinoses (NCLs) are a group of inherited human and animal diseases characterized by progressive brain atrophy. A form in sheep is syntenic to the human CLN6 disease. Cell type specific neurodegeneration in these sheep was indicated by the distribution of GABAergic interneurons in coronal sections of normal and CLN6 affected sheep brains. A reduction of parvalbumin immunoreactive neurons in NCL cerebral cortex was the most striking feature. This was most pronounced in parietal cortex where very few positive cells remained. Calretinin immunoreactive somata in infragranular layers of the neocortex were also reduced while the number of calbindin positive cells was similar in affected and normal brains. There were fewer GAD immunoreactive neurons in the deeper layers of all NCL cortical areas examined. The parietal lobe was relatively more affected than frontal or temporal lobes while the cerebellum and the basal ganglia showed no signs of selective neuron loss. Since horizontally extending basket cells are mainly labelled by parvalbumin, the loss of these interneurons in the neocortex may render pyramidal neurons more excitable and compromise their co-ordinated output. In vitro, cultures of control and affected neurons from 60 to 70-day-old fetal brain hemispheres were examined for the presence of GABAergic and glutamatergic neurons. Different neurons developed distinct immunoreactivity to glutamate or GABA but the overall distribution was similar in normal and affected cultures. This culture system may provide a useful model to compare GABAergic cell function of normal and NCL affected neurons.


Assuntos
Interneurônios/química , Lipofuscinoses Ceroides Neuronais/patologia , Ácido gama-Aminobutírico/análise , Animais , Células Cultivadas , Imuno-Histoquímica , Interneurônios/citologia , Neocórtex/patologia , Corpos de Nissl , Parvalbuminas/análise , Ovinos , Coloração e Rotulagem
16.
Liver ; 21(4): 247-53, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11454187

RESUMO

BACKGROUND/AIMS: In chronic cholestatic liver diseases, biliary excretion of organic anions from blood into bile is impaired. The aim of this study was to identify the underlying mechanism. METHODS: Expression of the basolateral organic anion transporting polypeptide OATP-C (SLC21A6) and the canalicular multidrug resistance protein 2 (MRP2) was studied in patients with primary sclerosing cholangitis (PSC) (n=4), a chronic cholestatic liver disease, and in non-cholestatic controls (n=4) (two with chronic hepatitis C, one with idiopathic liver cirrhosis and one with fatty liver). Total RNA was isolated from liver tissue, reverse transcribed and subjected to polymerase chain reaction (PCR) amplification using primers specific for OATP-C, MRP2 and beta-actin. PCR products were quantified densitometrically. RESULTS: When normalized for beta-actin expression, the level of OATP-C mRNA in liver tissue of patients with PSC was 49% of controls (OATP-C/beta-actin 1.60+/-0.25 vs. 3.24+/-0.69; p<0.05) and the level of MRP2 mRNA was 27% of controls (MRP2/beta-actin 0.70+/-0.36 vs. 2.54+/-0.56; p<0.01). CONCLUSIONS: Both OATP-C and MRP2 are decreased as measured by mRNA level in PSC. Downregulation of OATP-C might be the consequence of impaired canalicular secretion of organic anions and could serve to reduce the organic anion load of cholestatic hepatocytes.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/biossíntese , Proteínas de Transporte/biossíntese , Colangite Esclerosante/metabolismo , Proteínas de Membrana Transportadoras , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Adulto , Idoso , Proteínas de Transporte de Ânions , Proteínas de Transporte/genética , Colangite Esclerosante/genética , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Proteína 2 Associada à Farmacorresistência Múltipla , Reação em Cadeia da Polimerase , RNA Mensageiro/análise
17.
Genomics ; 67(2): 179-87, 2000 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-10903843

RESUMO

We recently described a novel putative Ca(2+) channel gene, MTR1, which shows a high level of homology to the human TRPC7 gene and the melastatin 1 (MLSN1) gene, another Trp (transient receptor potential protein)-related gene whose transcript was found to be downregulated in metastatic melanomas. It maps to human chromosome band 11p15.5, which is associated with the Beckwith-Wiedemann syndrome and predisposition to a variety of neoplasias. Here we report the isolation and characterization of the murine orthologue Mtr1. The chromosomal localization on distal chromosome 7 places it in a cluster of imprinted genes, flanked by the previously described Tapa1 and Kcnq1 genes. The Mtr1 gene encodes a 4.4-kb transcript, present in a variety of fetal and adult tissues. The putative open reading frame consists of 24 exons, encoding 1158 amino acids. Transmembrane prediction algorithms indicate the presence of six membrane-spanning domains in the proposed protein. Imprinting analysis, using RT-PCR on RNA from reciprocal mouse crosses harboring a sequence polymorphism, revealed biallelic expression of Mtr1 transcripts at all stages and tissues examined.


Assuntos
Alelos , Canais de Cálcio/genética , Cromossomos/genética , Impressão Genômica , Proteínas de Membrana/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Mapeamento Cromossômico , Éxons , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Genes/genética , Humanos , Íntrons , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Homologia de Sequência de Aminoácidos , Canais de Cátion TRPC , Canais de Cátion TRPM , Distribuição Tecidual
18.
Eur J Clin Invest ; 30(2): 135-9, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10651838

RESUMO

BACKGROUND: Cholestyramine is the first-line treatment for cholestasis-induced pruritus and is prescribed along with ursodeoxycholic acid (UDCA) in patients with cholestatic liver diseases. Impairment of the intestinal absorption of endogenous hydrophobic bile acids by cholestyramine is well known. It is unclear, however, whether cholestyramine also impairs the absorption of the hydrophilic bile acid, UDCA, in man. AIMS: To study serum levels of UDCA and endogenous bile acids as well as endogenous bile acid synthesis during simultaneous or separate administration of UDCA and cholestyramine in vivo; and absorption of UDCA both in the presence and absence of its hydrophobic epimer, chenodeoxycholic acid (CDCA), by cholestyramine in vitro. PATIENTS AND METHODS: Five healthy subjects received UDCA (12.5 +/- 0.5 mg kg-1 daily) as a single dose for periods of 14 days with or without cholestyramine (4 g daily). Fasting serum levels of bile acids and of 7alpha-hydroxy-4-cholesten-3-one (alpha-HC), a measure of endogenous bile acid synthesis, were determined by gas chromatography and high pressure liquid chromatography, respectively. In vitro, bile acid solutions were incubated for 24 h in the presence or absence of cholestyramine, and bile acid concentrations were determined in the supernatant. RESULTS: Simultaneous administration of UDCA and cholestyramine in man led to a decrease of fasting serum levels of UDCA by 60% when compared to UDCA serum levels during administration of UDCA alone. In contrast, serum levels of endogenous bile acids were not affected and alpha-HC serum levels were found increased 2. 7-fold indicating stimulation of endogenous bile acid synthesis by cholestyramine. Administration of cholestyramine and UDCA at an interval of 5 h tended to diminish the effect of cholestyramine on UDCA serum levels. In vitro, conjugated and unconjugated UDCA were effectively bound by cholestyramine both in the presence and absence of hydrophobic bile acids. CONCLUSIONS: The results strongly support the recommendation to administer UDCA and cholestyramine at different times of day.


Assuntos
Colestase Intra-Hepática/tratamento farmacológico , Resina de Colestiramina/administração & dosagem , Prurido/tratamento farmacológico , Ácido Ursodesoxicólico/administração & dosagem , Adulto , Ácidos e Sais Biliares/sangue , Colestenonas/sangue , Doença Crônica , Esquema de Medicação , Quimioterapia Combinada , Jejum , Feminino , Humanos , Masculino , Ácido Ursodesoxicólico/sangue
19.
Eur Respir J ; 13(5): 1091-6, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10414409

RESUMO

The aim of the present study was to determine survival rates of obstructive sleep apnoea patients treated with continuous positive airway pressure (CPAP) and to investigate the prognostic value of pretreatment lung function and pulmonary haemodynamics. Two hundred and ninety-six patients, exhibiting > or = 20 apnoeas plus hypopnoeas per hour of sleep, were included. Patients were treated with nasal CPAP and regularly followed up. The cumulative survival rates were 0.96 (95% confidence interval (CI): 0.94-0.99) at 3 yrs and 0.93 (95% CI: 0.91-0.97) at 5 yrs. Most patients died from cardiovascular disease. Apart from age, covariates associated with a lower survival were the presence of a heavy smoking history, a low vital capacity, a low forced expiratory volume in one second (FEV1) and a high mean pulmonary artery pressure. Only three covariates were included by forward stepwise selection in the multivariate analysis, smoking habit (>30 pack-yrs), age and FEV1. The observed survival rates of the group as a whole were similar to those of the general population matched in terms of age, sex and smoking habit, except for patients between 50 and 60 yrs old who had reduced survival. This difference disappeared when patients of the present study with an associated chronic obstructive pulmonary disease were excluded from the comparison. In conclusion, survival of obstructive sleep apnoea patients treated with nasal continuous positive airway pressure is near to that of the general population. The prognosis is worse in subgroups of patients with a history of heavy smoking and with an associated chronic obstructive pulmonary disease.


Assuntos
Respiração com Pressão Positiva , Síndromes da Apneia do Sono/terapia , Feminino , Humanos , Pneumopatias Obstrutivas/epidemiologia , Masculino , Pessoa de Meia-Idade , Respiração com Pressão Positiva/métodos , Prognóstico , Circulação Pulmonar/fisiologia , Testes de Função Respiratória , Fatores de Risco , Síndromes da Apneia do Sono/diagnóstico , Síndromes da Apneia do Sono/mortalidade , Fumar/epidemiologia , Taxa de Sobrevida
20.
Mol Genet Metab ; 67(2): 169-75, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10356317

RESUMO

Mutations in different genes underlie different forms of the neuronal ceroid lipofuscinoses (NCLs, Batten disease). Subunit c of mitochondrial ATP synthase specifically accumulates in most of them, including the juvenile CLN3 form and a sheep form orthologous to CLN6. Products of these genes are likely to be components of a complex or pathway for subunit c turnover, and their expression may be cross-regulated. Different bands, some with different subcellular distributions, were detected by antisera against different regions of CLN3 on Western blots of sheep tissues. Affected liver blots were the same as controls but a specific 50-kDa band was at higher concentration in affected brain homogenates than in controls. Others have also reported bands reacting differently to different CLN3 antibodies. When the 3' end of sheep CLN3 cDNA was amplified by RT-PCR, four mRNA splicing variants were found. Different CLN3 splicing variants at the 5' end of the human cDNA have been reported. These mRNA splicing variants may account the variation of epitope distribution and the different subcellular locations of the CLN3 gene product(s). The predicted size of the unmodified CLN3 protein is 48 kDa. Significantly higher molecular weight bands may correspond to oligomers of a CLN3 isoform or to a CLN3 isoform tightly bound to another protein.


Assuntos
Glicoproteínas de Membrana , Chaperonas Moleculares , Lipofuscinoses Ceroides Neuronais/genética , Proteínas/genética , Splicing de RNA/genética , Ovinos/genética , Sequência de Aminoácidos , Animais , Western Blotting/veterinária , Variação Genética , Humanos , Fígado/química , Dados de Sequência Molecular , Peso Molecular , Peptídeos/síntese química , Peptídeos/imunologia , Ligação Proteica , Proteínas/química , Proteínas/imunologia , RNA Mensageiro/biossíntese , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico
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