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Severe chronic rhinosinusitis with nasal polyps (CRSwNP), a form of diffuse bilateral (usually type 2) CRS, is a debilitating disease with a significant impact on quality of life (QoL). With novel knowledge and treatment options becoming available, there is a growing need to update or revise key definitions to enable communication across different specialties dealing with CRS, and to agree on novel goals of care in CRSwNP. The European Forum for Research and Education in Allergy and Airway diseases (EUFOREA) and EPOS expert members discussed how to measure treatment responses and set new treatment goals for CRSwNP. In this paper a consensus on a list of definitions related to CRSwNP is provided: control, remission, cure, recurrence/exacerbation, treatable traits, remodeling, progression, and disease modification. By providing these definitions, the involved experts hope to improve communication between all stakeholders involved in CRSwNP treatment for use in routine care, basic and clinical research and international guidelines aimed to harmonize and optimize standard of care of patients with CRSwNP in the future.
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Pólipos Nasales , Rinitis , Sinusitis , Humanos , Sinusitis/terapia , Rinitis/terapia , Enfermedad Crónica , Pólipos Nasales/terapia , Pólipos Nasales/complicaciones , Calidad de VidaRESUMEN
The small size of the mouse heart frequently imparts technical challenges when applying conventional in vivo imaging methods for assessing heart function. Here, we describe the use of high-frequency ultrasound imaging in conjunction with a size-tuned blood pool contrast agent for quantitatively assessing myocardial perfusion in living mice. A perflurocarbon microbubble formulation exhibiting a narrow size distribution was developed, and echogenicity was assessed at 18 MHz in vitro. Adult mice were subjected to permanent ligation of the left anterior descending artery. Ultrasound imaging was performed on day 7, and a cohort of intact mice was used as a control. Parasternal long-axis cine clips were acquired at 18 MHz before and after contrast administration. Reduced ejection fraction and increased end-systolic volume were observed in infarcted compared with control mice. In control animals, washin of the contrast agent was visible in all myocardial segments. Reduced contrast enhancement was observed in apical-posterolateral regions of all infarcted mice. A novel method for reslicing of the imaging data through the time domain provided a two-dimensional presentation of regional contrast agent washin, enabling convenient identification of locations exhibiting altered perfusion. Myocardial segments exhibiting diminished contractility were observed to have correspondingly low relative myocardial perfusion. The contrast agent formulation and methods demonstrated here provide the basis for simplifying routine in vivo estimation of infarct size in mice and may be particularly useful in longitudinal evaluation of revascularization interventions and assessment of peri-infarct ischemia. NEW & NOTEWORTHY Murine myocardial contrast echocardiography frequently suffers from poor sensitivity to contrast. Here, we formulated a novel size-tuned microbubble contrast agent and validated it for use with ultra-high-frequency ultrasound. A novel data method for evaluating myocardial perfusion based on reslicing the imaging data through the time domain is presented.
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Medios de Contraste/administración & dosificación , Ecocardiografía/métodos , Infarto del Miocardio/diagnóstico por imagen , Imagen de Perfusión Miocárdica/métodos , Animales , Circulación Coronaria , Modelos Animales de Enfermedad , Interpretación de Imagen Asistida por Computador , Masculino , Ratones Endogámicos C57BL , Microburbujas , Contracción Miocárdica , Infarto del Miocardio/fisiopatología , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Factores de TiempoRESUMEN
The initial stages of T-cell differentiation are characterized by a progressive commitment to the T-cell lineage, a process that involves the loss of alternative (myelo-erythroid, NK, B) lineage potentials. Aberrant differentiation during these stages can result in T-cell acute lymphoblastic leukemia (T-ALL). However, the mechanisms regulating the initial stages of human T-cell differentiation are obscure. Through loss of function studies, we showed BCL11B, a transcription factor recurrently mutated T-ALL, is essential for T-lineage commitment, particularly the repression of NK and myeloid potentials, and the induction of T-lineage genes, during the initial stages of human T-cell differentiation. In gain of function studies, BCL11B inhibited growth of and induced a T-lineage transcriptional program in T-ALL cells. We found previously unknown differentiation stage-specific DNA binding of BCL11B at multiple T-lineage genes; target genes showed BCL11B-dependent expression, suggesting a transcriptional activator role for BCL11B at these genes. Transcriptional analyses revealed differences in the regulatory actions of BCL11B between human and murine thymopoiesis. Our studies show BCL11B is a key regulator of the initial stages of human T-cell differentiation and delineate the BCL11B transcriptional program, enabling the dissection of the underpinnings of normal T-cell differentiation and providing a resource for understanding dysregulations in T-ALL.
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Diferenciación Celular/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Proteínas Represoras/genética , Linfocitos T/citología , Proteínas Supresoras de Tumor/genética , HumanosRESUMEN
C tactile fibers are a specialized group of fibers innervating the non-glabrous skin that are tuned to light gentle stroking applied with velocities between 1 and 10 cm/s. Those fibers add to the sensation of interpersonal caressing and pleasant touch. It is unclear whether people spontaneously apply touch that is tuned to optimally activate those fibers. This was investigated in three studies. In study one, 45 participants (21.8 ± 2.3 years, 24 women) were asked to stroke an artificial arm. In study two, 32 participants (28.3 ± 8.7 years, 16 women) were asked to stroke their partner. In study three, 11 parents (29.4 ± 5.7 years, 6 women) were asked to stroke their babies. Stroking velocity was tracked in all conditions. Stroking velocities were significantly slower in the partner touch and baby touch condition than in the artificial arm condition and all of the participants stroking their partner or baby used velocities that can activate C tactile fibers. We conclude that human social stroking is optimized for C tactile stimulation.
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Relaciones Interpersonales , Mecanorreceptores/fisiología , Fibras Nerviosas Amielínicas/fisiología , Conducta Social , Tacto/fisiología , Adolescente , Adulto , Brazo/fisiología , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Modelos Biológicos , Relaciones Padres-Hijo , Psicofísica , Parejas Sexuales , Adulto JovenRESUMEN
Single fluorophores and single-pair fluorescence resonance energy transfer were studied with a new confocal fluorescence microscope that allows, for the first time, the wavelength and emission time of each detected photon to be simultaneously measured with single molecule sensitivity. In this apparatus, the photons collected from the sample are imaged through a dispersive optical system onto a time and position sensitive photon detector. For each detected photon the detection system records its wavelength, its emission time relative to the excitation pulse, and its absolute emission time. A histogram over many photons can generate a full fluorescence spectrum and correlated decay plot for a single molecule for any time interval. At the single molecule level, this approach makes possible entirely new types of temporal and spectral correlation spectroscopies. This paper presents our initial results on simultaneous time- and wavelength-resolved fluorescence measurements of single rhodamine 6G (R6G), tetramethylrhodamine (TMR), and Cy3 molecules embedded in thin films of poly(methyl methacrylate) (PMMA), and of single-pair fluorescence resonance energy transfer between two Alexa fluorophores spaced apart by a short polyproline peptide.
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UNLABELLED: Iodine-123-iodobenzofuran (IBF) is a potent dopamine D2 receptor ligand suited for quantitative receptor studies. The purpose of this study was to evaluate three noninvasive methods of estimating the receptor parameter k3/k4 in humans with IBF-SPECT. METHODS: Scans were acquired every 5 min for 180 min using a triple-headed SPECT system following a bolus injection of IBF (296 +/- 37 MBq) in 14 normal volunteers. k3/k4 was estimated by the peak equilibrium ratio (RPE) method and two proposed methods: a variation of the graphic method that derives the ratio of ligand distribution volumes (RV) and area ratio (RA) method, in which the ratio is calculated from the areas under the specific binding and nondisplaceable activity curves. RESULTS: The mean RPE, RV and RA were 2.74 +/- 0.40, 3.06 +/- 0.42 and 2.26 +/- 0.28, respectively. Both RPE and RA underestimated RV. The relationship between RPE or RA and RV was linear (p < or = 10(-5), RA showed higher correlation (r = 0.94) with RV than did RPE (r = 0.90). Simulations based on a tracer kinetic model showed that RV, unlike RPE or RA, is affected by neither regional cerebral blood flow (rCBF) nor peripheral clearance rate (CR) of IBF. All three measures showed a significant decline with increasing age (r = 0.54-0.58, p < 0.05). CONCLUSION: RV is preferred because it provides a theoretically valid estimate of k3/k4, independently of rCBF or CR. Alternatively, RA might be preferred to RPE because the former is simpler than the latter to implement yet the former provides a measure that equally well correlates with k3/k4.
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Benzofuranos , Encéfalo/diagnóstico por imagen , Radioisótopos de Yodo , Pirrolidinas , Receptores de Dopamina D2/análisis , Tomografía Computarizada de Emisión de Fotón Único , Adulto , Benzofuranos/farmacocinética , Encéfalo/metabolismo , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Modelos Biológicos , Pirrolidinas/farmacocinética , Factores de TiempoRESUMEN
We have characterized the spliced transcripts of nef and envelope genes of SIVagm from African green monkey of the sabaeus subspecies. Most of the transcripts we have studied, representing the most abundant mRNA species in our assay, have undergone a specific splicing event that removes a part of the trans-activation response (TAR) element. This region is predicted to form a stable secondary structure (four stem-loop elements in SIVagm-sab) that affects the trans-activation of viral gene expression by Tat and the translation of the viral transcripts. Contrary to what is observed in other viruses, in which this R-region splicing has also been described (e.g., HIV-2), the LTR splicing in SIVagm-sab removes part of the first stem-loop and the following ones, nearly completely disrupting the TAR element secondary structure. Because LTR splicing seems to be a conserved feature among the strains we have characterized, these results suggest that this phenomenon could have important consequences for virus replication, pathogenicity, and latency.
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Chlorocebus aethiops/virología , Productos del Gen env/genética , Productos del Gen nef/genética , Virus de la Inmunodeficiencia de los Simios/genética , Animales , Secuencia de Bases , ADN Complementario/biosíntesis , ADN Complementario/genética , ADN Recombinante , Iminoácidos , Datos de Secuencia Molecular , Alineación de SecuenciaRESUMEN
An analytical method based upon near infra-red reflectance measurements on solid samples is described for the determination of the polymorphic transformation of an active ingredient in a solid dosage form matrix. Calculations were performed using multiple linear regression techniques. The method was applied to mixtures of two polymorphic forms of a new chemical entity in a formulation matrix and gave recoveries close to the expected values with an acceptable reproducibility.
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Employees (N = 194) from a wide variety of organizations participated in this study aimed at describing the attitudes of individuals who refuse to respond to an employee survey request (noncompliants). Noncompliants, in comparison with those individuals who would comply with the survey request, possessed greater intentions to quit, less organizational commitment, and less satisfaction toward supervisors and their own jobs. Noncompliants also possessed more negative beliefs regarding how their organization handles employee survey data (e.g., does not act on survey data). No significant differences were found for work-related demographic variables, satisfaction with pay, and satisfaction with promotion opportunities. Implications for survey research are discussed along with methods to address nonresponse and noncmpliance.
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Actitud , Conducta Cooperativa , Recolección de Datos , Administración de Personal , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos PsicológicosRESUMEN
We studied the contribution of non human primates to the transmission of yellow fever and HIV in the wild. We demonstrate the consequences of the modification of ecosystems on the emergence of new viral diseases and the reappearance of diseases believed to be eradicated. In the primary forest, the natural yellow fever cycle is limited to monkeys and mosquitoes living high in the canopy. Transmission to man is an anomaly, requiring the circumstances found in the forest and savanna contact zones, where man has changed the forest to a mosaic and decimated the simian population, favoring contact between mosquitoes and man. In these contact zones, the amaril virus circulates in episodic cycles. During each episode, most of the local monkeys are infected, and thereby acquire immunity. Yellow fever can only reappear subsequently when a sufficiently large new generation of non-immune young monkeys is available. Monkeys do not become ill when infected, presumably as a result of typical host-parasite cross selection having led to the development of a balance between the parasite and its host. AIDS is a transmissible viral disease which appeared recently. Various African non-human primates are hosts to SIV, a retrovirus closely related to HIV which causes AIDS in man. SIV-infected African monkeys do not develop AIDS. However, when used to infect species from other continents (for example Asian macaco monkeys) SIV can cause AIDS. Does pathogenicity appear during transmission of the virus from one primate host to another, and is this the case for human AIDS? Experimental inoculations, the demonstration of SIVagm in other species, the mosaic structure of the genome (implying cross species recombinations), and the high probability of cross-species transmission of the viruses in the wild all favor this idea. Possibly counterbalancing the pessimism about the development of an HIV1 vaccine in the near future, the non-human SIV models holds out some hope. The emergence of new diseases, such as Ebola, or diseases from other niches, and the reappearance of diseases believed to be eradicated, are frequent when man modifies the ecosystem, the structure and balance of which he does not control, and when he puts into contact species which have never met before.
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Animales Salvajes/virología , Ecosistema , Infecciones por VIH/transmisión , Primates/virología , Fiebre Amarilla/transmisión , Zoonosis/transmisión , Vacunas contra el SIDA , África , Enfermedades de los Animales/transmisión , Enfermedades de los Animales/virología , Animales , Animales Salvajes/genética , Animales Salvajes/inmunología , Asia , Conducta Animal , Culicidae/virología , Modelos Animales de Enfermedad , Vectores de Enfermedades , Ecología , Genoma Viral , Haplorrinos/virología , Fiebre Hemorrágica Ebola/transmisión , Humanos , Inmunidad Activa , Insectos Vectores , Primates/genética , Primates/inmunología , Recombinación Genética , Síndrome de Inmunodeficiencia Adquirida del Simio/transmisión , Virus de la Inmunodeficiencia de los Simios/genética , Virus de la Inmunodeficiencia de los Simios/patogenicidad , Clima Tropical , Virulencia , Zoonosis/virologíaAsunto(s)
Chlorocebus aethiops/virología , Infecciones por Deltaretrovirus/complicaciones , Infecciones por Retroviridae/complicaciones , Síndrome de Inmunodeficiencia Adquirida del Simio/complicaciones , Virus de la Inmunodeficiencia de los Simios/patogenicidad , Virus Linfotrópico T Tipo 1 de los Simios/patogenicidad , Animales , Factores de Riesgo , SenegalRESUMEN
The group of seronegative spondyloarthropathies consists of ankylosing spondylitis, psoriatic arthritis, Reiter's disease, enteropathic spondylitis, and a fifth entity known as undifferentiated spondyloarthropathy. All of these diseases share common clinical and radiographic features with characteristic involvement of the sacroiliac joints, spine, and to various degrees, the peripheral joints. Although plain radiographs are the first line of imaging investigation, they are often insensitive for demonstrating the early changes of sacroiliitis, an important feature for establishing the early diagnosis of seronegative spondyloarthropathy. Other imaging modalities, including conventional tomography, bone scintigraphy, and computed tomography, have improved visualization of inflammatory changes at the sacroiliac joints. This article will review these modalities and emphasize the role of magnetic resonance imaging. By directly imaging changes in the synovium, articular cartilage, and subchondral bone, findings on magnetic resonance imaging are the most sensitive and specific for sacroiliitis and other changes in the axial skeleton. Its role and that of ultrasound in the assessment of the peripheral joints will also be highlighted.
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Imagen por Resonancia Magnética , Espondiloartropatías/diagnóstico por imagen , Espondiloartropatías/diagnóstico , Tomografía Computarizada por Rayos X , Adulto , Artrografía , Huesos/diagnóstico por imagen , Niño , Humanos , Inflamación , Estudios Longitudinales , Cintigrafía , Articulación Sacroiliaca , Sensibilidad y Especificidad , Columna Vertebral/diagnóstico por imagen , Espondiloartropatías/clasificación , Espondilitis Anquilosante/diagnósticoRESUMEN
Substrate inhibition in tyrosine hydroxylase (TH) was analyzed by deletion mutagenesis. The deletion mutant TH 156/456 was the smallest section of TH to retain substrate inhibition. The TH 156/456 was monomeric, and so multimer formation does not play a role in substrate inhibition in TH. Further deletion at the N terminus to residue 169 produced a TH molecule with no substrate inhibition but high activity. A mutagenic scan of this region showed that mutations at Trp166 were responsible for this phenotype. A screen of a library of TH molecules containing random mutations identified three other mutants that had lost substrate inhibition but retained high activity. The results in this report are consistent with a model in which substrate inhibition acts through an allosteric mechanism.
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Análisis Mutacional de ADN , Tirosina 3-Monooxigenasa/genética , Secuencia de Aminoácidos , Fenómenos Químicos , Química Física , Eliminación de Gen , Biblioteca de Genes , Mutagénesis Sitio-Dirigida , Mutación/genética , Fenotipo , Especificidad por Sustrato , Tirosina 3-Monooxigenasa/químicaRESUMEN
In order to probe the structural and functional properties of a central region of apolipoprotein A-I (apoA-I), we engineered mutants of the mature form of the protein and expressed them using the baculovirus/insect cell expression system. The mutations which targeted the region of apoA-I between amino acids 140 and 150 included: (i) deletion of the region 140-150 (apoA-I(Delta140-150)); (ii) substitution of arginine 149 with valine (apoA-I(R149V)); (iii) substitution of proline 143 with alanine (apoA-I(P143A)); (iv) deletion of region 63-73 (apoA-I(Delta63-73)), which has structural properties similar to 140-150; and (v) a chimeric protein substituting amino acids 140-150 with amino acids 63-73 (apoA-I(140-150 --> 63-73)). The efficiencies of synthesis were vastly different for the various mutants as follows: apoA-I(R149V) > apoA-I(140-150 --> 63-73) > apoA-I(Delta63-73) > apoA-I(P143A) > apoA-I > apoA-I(Delta140-150). About 50% of the synthesized wild type and all apoA-I mutants was retained in the cells. During expression of apoA-I(R149V) an unusual spontaneous recombination occurred. In addition to the expected mutant, another form of apoA-I with an apparent M(r) of 36K was produced which consisted of a duplication of the amino-terminal end of apoA-I, from the prepeptide through to amino acid 62, linked to the original pre-apoA-I(R149V) sequence via a 4-amino-acid linker. Despite the fact that this form of apoA-I carries two prepeptides and consequently two cleavage sites, there was little, if any, cleavage at the internal cleavage site. During expression, less than 20% of this mutant was retained in the cells. These results demonstrate that at least in the model of insect cells, the efficiency of apoA-I synthesis, processing, and secretion depends on apoA-I secondary structure and/or folding.
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Apolipoproteína A-I/genética , Secuencias de Aminoácidos/genética , Secuencia de Aminoácidos , Animales , Apolipoproteína A-I/biosíntesis , Apolipoproteína A-I/metabolismo , Baculoviridae , Secuencia de Bases , Western Blotting , Células Cultivadas , Expresión Génica , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Mutación , Ingeniería de Proteínas , Estructura Secundaria de Proteína/genética , Recombinación Genética , Relación Estructura-ActividadRESUMEN
Sterol regulatory element-binding proteins (SREBPs) are membrane-bound transcription factors that increase the synthesis of fatty acids as well as cholesterol in animal cells. All three SREBP isoforms (SREBP-1a, -1c, and -2) are subject to feedback regulation by cholesterol, which blocks their proteolytic release from membranes. Previous data indicate that the SREBPs are also negatively regulated by unsaturated fatty acids, but the mechanism is uncertain. In the current experiments, unsaturated fatty acids decreased the nuclear content of SREBP-1, but not SREBP-2, in cultured human embryonic kidney (HEK)-293 cells. The potency of unsaturated fatty acids increased with increasing chain length and degree of unsaturation. Oleate, linoleate, and arachidonate were all effective, but the saturated fatty acids palmitate and stearate were not effective. Down-regulation occurred at two levels. The mRNAs encoding SREBP-1a and SREBP-1c were markedly reduced, and the proteolytic processing of these SREBPs was inhibited. When SREBP-1a was produced by a cDNA expressed from an independent promoter, unsaturated fatty acids reduced nuclear SREBP-1a without affecting the mRNA level. There was no effect when the cDNA encoded a truncated version that was not membrane-bound. When administered together, sterols and unsaturated fatty acids potentiated each other in reducing nuclear SREBP-1. In the absence of fatty acids, sterols did not cause a sustained reduction of nuclear SREBP-1, but they did reduce nuclear SREBP-2. We conclude that unsaturated fatty acids, as well as sterols, can down-regulate nuclear SREBPs and that unsaturated fatty acids have their greatest inhibitory effects on SREBP-1a and SREBP-1c, whereas sterols have their greatest inhibitory effects on SREBP-2.
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Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Proteínas de Unión al ADN/metabolismo , Ácidos Grasos Insaturados/metabolismo , Secuencia de Bases , Línea Celular , Cartilla de ADN , Proteínas de Unión al ADN/genética , Humanos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles , Proteína 2 de Unión a Elementos Reguladores de Esteroles , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
Dynamics in the transition state region of the bimolecular OH + H2O-->H2O + OH hydrogen exchange reaction have been studied by photoelectron-photofragment coincidence spectroscopy of the H3O2- negative ion and its deuterated analog D3O2-. The data reveal vibrationally resolved product translational energy distributions. The total translational energy distribution shows a vibrational progression indicating excitation of the antisymmetric stretch of the water product. Electronic structure calculations at the QCISD level of theory support this analysis. Examination of the translational energy release between the neutral products reveals a dependence on the product vibrational state. These data should provide a critical test of ab initio potential energy surfaces and dynamics calculations.
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Hidróxidos/química , Agua/química , Cinética , FotoquímicaRESUMEN
To achieve expression of human mature apolipoprotein A-I (apoA-I) in the baculovirus-insect cell expression system, the propeptide encoding region of full-length preproapoA-I was deleted using polymerase chain reaction and the resulting cDNA was cloned into BacPak8 plasmid. After transfection into Sf21 insect cells and plaque purification, mature human apoA-I was secreted by the infected cells into the medium as determined by immunoblotting, amino-terminal sequencing, and molecular weight determination. In both monolayer cell cultures, and in suspension cell culture, maximum expression was achieved by the fifth day. For the first 4 days, 50 to 70% of the synthesized apoA-I was retained in the cells. This intracellular apoA-I was represented by mature apoA-I as shown by immunoblotting and amino-terminal sequencing. Further incubation resulted in a sharp decrease in the cell apoA-I content without a corresponding increase in protein in the medium and most likely represents intracellular degradation of the protein. We conclude that the deletion of the propeptide, while not preventing the correct cleavage of prepeptide during intracellular processing, results in reduced secretion of mature apoA-I. The baculovirus-insect cell expression system described in this study provides a useful method for producing recombinant mature apoA-I and is a potential tool for understanding the function of propeptide in intracellular transport and secretion of apoA-I from cells.
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Apolipoproteína A-I/biosíntesis , Apolipoproteína A-I/metabolismo , Baculoviridae/genética , Líquido Intracelular/metabolismo , Precursores de Proteínas/biosíntesis , Precursores de Proteínas/metabolismo , Señales de Clasificación de Proteína/metabolismo , Spodoptera/genética , Secuencia de Aminoácidos , Animales , Apolipoproteína A-I/genética , Secuencia de Bases , Línea Celular , Vectores Genéticos/metabolismo , Humanos , Datos de Secuencia Molecular , Precursores de Proteínas/genética , Procesamiento Proteico-Postraduccional , Señales de Clasificación de Proteína/genética , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genéticaRESUMEN
Through suppressive subtractive hybridization, we identified a new gene whose transcription is induced by sterol regulatory element-binding proteins (SREBPs). The gene encodes acetyl-CoA synthetase (ACS), the cytosolic enzyme that activates acetate so that it can be used for lipid synthesis or for energy generation. ACS genes were isolated previously from yeast, but not from animal cells. Recombinant human ACS was produced by expressing the cloned cDNA transiently in human cells. After purification by nickel chromatography, the 701-amino acid cytosolic enzyme was shown to function as a monomer. The recombinant enzyme produced acetyl-CoA from acetate in a reaction that required ATP. As expected for a gene controlled by SREBPs, ACS mRNA was induced when cultured cells were deprived of sterols and repressed by sterol addition. The pattern of regulation resembled the regulation of enzymes of fatty acid synthesis. ACS mRNA was also elevated in livers of transgenic mice that express dominant-positive versions of all three isoforms of SREBP. We conclude that ACS mRNA, and hence the ability of cells to activate acetate, is regulated by SREBPs in parallel with fatty acid synthesis in animal cells.
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Acetato CoA Ligasa/metabolismo , Proteínas Potenciadoras de Unión a CCAAT , Proteínas de Unión al ADN/metabolismo , Secuencias Hélice-Asa-Hélice , Leucina Zippers , Proteínas Nucleares/metabolismo , Factores de Transcripción/metabolismo , Acetato CoA Ligasa/genética , Secuencia de Aminoácidos , Animales , Cricetinae , Células HeLa , Humanos , Ratones , Datos de Secuencia Molecular , ARN Mensajero/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de EsterolesRESUMEN
OBJECTIVE: to ascertain if standard gestational age charts can be used to accurately predict the gestational age of fetuses of first-generation Oriental immigrants to Canada. PATIENTS AND METHODS: Over a 3-year period, all patients presenting for obstetric ultrasound examinations were invited to participate in the study. The authors recorded biparietal diameter, head circumference, femur length and abdominal circumference for 139 fetuses in the second and third trimesters. A study performed in the first trimester was used as the baseline for gestational age. The data for 126 of the fetuses were complete, and these data were used for the analysis. RESULTS: For 77 of the fetuses, both parents were Oriental, and for 49, one or both parents were not Oriental; the latter constituted the control group. A total of 1008 individual measurements were obtained, and of these, all but 14 fell within two standard deviations of the norm, according to standard gestational age charts. Of the abnormal measurements, seven were obtained from five fetuses with Oriental parents, and seven were obtained from six fetuses in the control group. The difference between the two groups in the proportion of measurements falling either above or below two standard deviations from the norm was not statistically significant (Fisher's exact test, p = 0.41694). CONCLUSION: The authors conclude that standard gestational age charts can be used to determine gestational age in first-generation Oriental immigrants to Canada.
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Feto/anatomía & histología , Edad Gestacional , Antropometría/métodos , Asia/etnología , Canadá , Femenino , Humanos , Valor Predictivo de las Pruebas , Embarazo , Ultrasonografía PrenatalRESUMEN
Variations were observed in prealbumin, transferrin, ceruloplasmin, haptoglobin, PGM-II and AK systems in various subspecies of Cercopithecus aethiops. The electrophoretic distance between three forms seems to indicate an intermediary status between populations and subspecies. The reasons for this moderate differentiation are discussed with regard to divergence of ethological characters, as recently studied.