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1.
Exp Parasitol ; 249: 108499, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36898495

RESUMO

Leucine, isoleucine, and valine, collectively termed Branched Chain Amino Acids (BCAA), are hydrophobic amino acids (AAs) and are essential for most eukaryotes since in these organisms they cannot be biosynthesized and must be supplied by the diet. These AAs are structurally relevant for muscle cells and, of course, important for the protein synthesis process. The metabolism of BCAA and its participation in different biological processes in mammals have been relatively well described. However, for other organisms as pathogenic parasites, the literature is really scarce. Here we review the BCAA catabolism, compile evidence on their relevance for pathogenic eukaryotes with special emphasis on kinetoplastids and highlight unique aspects of this underrated pathway.


Assuntos
Aminoácidos de Cadeia Ramificada , Isoleucina , Animais , Aminoácidos de Cadeia Ramificada/metabolismo , Leucina , Isoleucina/metabolismo , Aminoácidos , Eucariotos , Mamíferos/metabolismo
2.
Rheumatol Int ; 41(7): 1329-1335, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33891159

RESUMO

Monocytes play a key role in pathophysiology of antiphospholipid syndrome (APS), nevertheless it is unclear if microRNA expression is associated with particular APS features. Identify whether miR-19b-3p and miR-20a-5p expression in monocytes are associated with hallmarks of the APS. Fifty-seven APS patients and 18 healthy controls were studied. Expression of miR-19b-3p and miR-20a-5p was measured in monocytes by RT-qPCR. Both miR-19b-3p (AUC = 0.835, 95% CI 0.733-0.938; P < 0.001) and miR-20a-5p (AUC = 0.857, 0.757-0.957; P < 0.001) discriminated APS patients from healthy individuals. A cut-off point of 1.98 for miR-19-3p and 2.18 for miR-20a-5p showed that APS patients with low microRNA expression had higher levels of IgM and IgG anticardiolipin antibodies than patients with high microRNA expression. In addition, APS patients with low microRNA expression had higher IgG anti-ß2 glycoprotein I antibody levels than their counterparts with high microRNA expression. Finally, miR-19b-3p and miR-20a-5p expression levels were significantly higher in APS patients using oral anticoagulants. Monocyte expression of miR-19b-3p and miR-20a-5p is low in APS, and patients with the lowest microRNA expression presented the highest levels of antiphospholipid antibodies.


Assuntos
Anticorpos Antifosfolipídeos/sangue , Síndrome Antifosfolipídica/metabolismo , MicroRNAs/metabolismo , Monócitos/metabolismo , Adulto , Síndrome Antifosfolipídica/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
Clin Exp Immunol ; 199(2): 230-243, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31631328

RESUMO

Smoking increases susceptibility to becoming infected with and developing tuberculosis. Among the components of cigarette smoke, nicotine has been identified as the main immunomodulatory molecule; however, its effect on the innate immune system is unknown. In the present study, the effect of nicotine on molecules of the innate immune system was evaluated. Lung epithelial cells and macrophages were infected with Mycobacterium tuberculosis (Mtb) and/or treated with nicotine. The results show that nicotine alone decreases the expression of the Toll-like receptors (TLR)-2, TLR-4 and NOD-2 in all three cell types, as well as the production of the SP-D surfactant protein in type II pneumocytes. Moreover, it was observed that nicotine decreases the production of interleukin (IL)-6 and C-C chemokine ligand (CCL)5 during Mtb infection in epithelial cells (EpCs), whereas in macrophages derived from human monocytes (MDMs) there is a decrease in IL-8, IL-6, tumor necrosis factor (TNF)-α, IL-10, CCL2, C-X-C chemokine ligand (CXCL)9 and CXCL10 only during infection with Mtb. Although modulation of the expression of cytokines and chemokines appears to be partially mediated by the nicotinic acetylcholine receptor α7, blocking this receptor found no effect on the expression of receptors and SP-D. In summary, it was found that nicotine modulates the expression of innate immunity molecules necessary for the defense against tuberculosis.


Assuntos
Células Epiteliais Alveolares/imunologia , Regulação da Expressão Gênica/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Macrófagos/imunologia , Mycobacterium tuberculosis/imunologia , Nicotina/farmacologia , Tuberculose Pulmonar/imunologia , Células A549 , Células Epiteliais Alveolares/microbiologia , Células Epiteliais Alveolares/patologia , Citocinas/imunologia , Regulação da Expressão Gênica/imunologia , Humanos , Macrófagos/microbiologia , Macrófagos/patologia , Proteína Adaptadora de Sinalização NOD2/imunologia , Receptor 2 Toll-Like/imunologia , Receptor 4 Toll-Like/imunologia , Tuberculose Pulmonar/patologia
4.
Phys Rev Lett ; 125(17): 170502, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33156670

RESUMO

We present an efficient approach to achieving arbitrary, high-fidelity control of a multilevel quantum system using optimal control techniques. As an demonstration, we implement a continuous, software-defined microwave pulse to realize a 0↔2 SWAP gate that achieves an average gate fidelity of 99.4%. We describe our procedure for extracting the system Hamiltonian, calibrating the quantum and classical hardware chain, and evaluating the gate fidelity. Our work represents an alternative, fully generalizable route towards achieving universal quantum control by leveraging optimal control techniques.

5.
Lupus ; 28(3): 427-431, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30717622

RESUMO

OBJECTIVE: The study aims to investigate the ovarian reserve in premenopausal women with antiphospholipid syndrome (APS) and to evaluate whether it is associated with cumulative organ damage or the risk of clinical complications. METHODS: This single-center study was conducted in 23 premenopausal female patients (10 with primary APS and 13 with secondary APS) and 24 healthy volunteers. Serum anti-Müllerian hormone (AMH) levels were measured by enzyme-linked immunoassay. Disease-specific organ damage (DIAPS score) and the risk of clinical complications (aGAPSS score) were additionally evaluated in APS patients. RESULTS: Serum AMH levels were similar in APS patients (median 6.06, interquartile range 4.31-7.54 ng/ml) and in controls (4.87, 2.64-6.40 ng/ml; P = 0.116), and no differences were observed between the primary (6.60, 5.49-8.88 ng/ml) and secondary (6.06, 3.91-7.30 ng/ml; P = 0.532) forms of the syndrome. In individuals with APS, serum AMH levels correlated inversely with the aGAPSS score (rho-0.421, 95% confidence intervals -0.716 to -0.001; P = 0.045), while no associations were observed with the DIAPS score (rho-0.001, -0.423 to 0.422; P = 0.996). CONCLUSIONS: Ovarian reserve is not reduced in premenopausal women with APS. In addition, serum AMH levels may reflect the risk of APS-related clinical complications but not the burden of disease-specific organ damage.


Assuntos
Síndrome Antifosfolipídica/sangue , Reserva Ovariana/imunologia , Adulto , Hormônio Antimülleriano/sangue , Síndrome Antifosfolipídica/complicações , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Pessoa de Meia-Idade , Pré-Menopausa
6.
Scand J Rheumatol ; 45(2): 151-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26375423

RESUMO

OBJECTIVES: The prevailing linear reductionist medical model seems unable to explain complex multisymptomatic illnesses such as fibromyalgia (FM) and similar maladies. Paradigms derived from the complexity theory may provide a coherent framework for these elusive illnesses. Along these lines is the proposal that FM represents a degradation of our main complex adaptive system (the autonomic nervous system, ANS), in a failed effort to adjust to a hostile environment. Healthy complex systems have fractal structures. Heart rate fractal-like variability reflects resilient ANS performance. Our aim was to measure the heart rate variability (HRV) fractal scaling index in FM patients and to correlate this index with clinical symptoms. METHOD: We studied 30 women with FM and 30 controls. All participants filled out questionnaires assessing the severity of FM. The HRV fractal scaling index was estimated during 24 h using detrended fluctuation analysis (DFA). RESULTS: The fractal scaling index alpha-1 was higher in FM patients than in controls (mean ± sd: 1.22 ± 0.10 vs. 1.16 ± 0.09; p = 0.031). There was a positive correlation between the fractal scaling index alpha-1 and the visual analogue scale (VAS) for depression (Spearman's ρ = 0.36, p = 0.04). CONCLUSIONS: The heart rate fractal exponent alpha-1 is altered in FM patients, suggesting a rigid ANS performance. This tangible non-linear finding supports the notion that FM may represent a degradation of our main complex adaptive system, namely the ANS.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Fibromialgia/fisiopatologia , Fractais , Frequência Cardíaca , Adulto , Estudos de Casos e Controles , Eletrocardiografia Ambulatorial , Feminino , Humanos , Índice de Gravidade de Doença , Inquéritos e Questionários
7.
Clin Exp Rheumatol ; 32(2): 162-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24480124

RESUMO

OBJECTIVES: We sought to determine the effect of statin therapy on the levels of proinflammatory/prothrombotic markers and disease activity scores in patients with SLE in a multi-ethnic, multi-centre cohort (LUMINA). METHODS: Plasma/serum samples from SLE patients placed on statins (n=21) therapy taken before and after at least 6 months of treatment were tested. Disease activity was assessed using SLAM-R scores. Interleukin (IL)-1ß, IL-6, IL-8, tumour necrosis factor (TNF)-α, vascular endothelial growth factor (VEGF) and soluble CD40 ligand (sCD40L) levels were determined by a multiplex immunoassay. Soluble intercellular cell adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM)-1 and anticardiolipin (aCL) antibodies were evaluated using ELISA assays while high sensitivity C-reactive protein (hsCRP) was assessed by nephelometry. Plasma/serum samples from frequency- matched healthy donors were used as controls. RESULTS: Levels of IL-6, VEGF, sCD40L and TNF-α were significantly elevated in SLE patients versus controls. Statin therapy resulted in a significant decrease in SLAM-R scores (p=0.0199) but no significant changes in biomarker levels were observed. There was no significant association of biomarkers with SLAM-R scores. CONCLUSIONS: Statin therapy resulted in significant clinical improvement in SLE patients, underscoring the use of statins in the treatment of SLE.


Assuntos
Biomarcadores/sangue , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Lúpus Eritematoso Sistêmico , Adulto , Proteína C-Reativa/análise , Ligante de CD40/sangue , Etnicidade , Feminino , Humanos , Molécula 1 de Adesão Intercelular/sangue , Interleucinas/sangue , Estudos Longitudinais , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/fisiopatologia , Masculino , Gravidade do Paciente , Porto Rico/epidemiologia , Projetos de Pesquisa , Resultado do Tratamento , Fator de Necrose Tumoral alfa/sangue , Estados Unidos/epidemiologia , Molécula 1 de Adesão de Célula Vascular/sangue
8.
Heliyon ; 9(5): e16189, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37234612

RESUMO

Pterygium is one of the most frequent pathologies in ophthalmology, and is a benign, overgrowth of fibrovascular tissue, often with a wing-like appearance, from the conjunctiva over the cornea. It is composed of an epithelium and highly vascular, sub-epithelial, loose connective tissue. There is much debate surround the pathogenesis of pterygium and a number of theories have been put forward including genetic instability, cellular proliferation, inflammatory influence, and degeneration of connective tissue, angiogenesis, aberrant apoptosis and viral infection. At present, the involvement of human papillomavirus (HPV) in the genesis of pterygium is controversial, as have reported that HPV is present in 58% of cases, while others have failed to detect HPV in pterygium. In this study, we evaluated the presence and viral genotype of HPV DNA in pterygia and healthy conjunctiva sample, and virus integration into the cellular genome. Forty primary pterygia samples and 12 healthy conjunctiva samples were analyzed to HPV DNA presence by polymerase chain reaction, using MY09/MY11 primers of HPV-L1 gene. Viral genotype was identified by DNA sequence analysis of this amplicon. HPV integration into the cellular genome was analyzed by western blot detecting HPV-L1 capsid protein. Presence of HPV was observed in 19 of the 40 pterygia samples. In contrast, healthy conjunctiva samples were negative. To determine virus type, sequence analyses were performed. Interestingly, 11 out of the 19-pterygium samples were identified as HPV-11 type, meanwhile, the remaining 8 pterygium samples were identified as HPV-18. HPV-L1 capsid protein were found only in 3 out of the 10 samples studied. In conclusion, our study identified the presence of HPV DNA exclusively in pterygium samples and described HPV-11 and -18 genotypes. Our results suggest that HPV may be involved in the pathogenesis of pterygium. On the other hand, the expression of the L1-HPV protein suggests viral integration into the cellular genome.

9.
Lupus ; 21(8): 830-5, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22343096

RESUMO

OBJECTIVE: We sought to determine the effect of hydroxychloroquine therapy on the levels proinflammatory/prothrombotic markers and disease activity scores in patients with systemic lupus erythematosus (SLE) in a multiethnic, multi-center cohort (LUMINA). METHODS: Plasma/serum samples from SLE patients (n = 35) were evaluated at baseline and after hydroxychloroquine treatment. Disease activity was assessed using SLAM-R scores. Interferon (IFN)-α2, interleukin (IL)-1ß, IL-6, IL-8, inducible protein (IP)-10, monocyte chemotactic protein-1, tumor necrosis factor (TNF)-α and soluble CD40 ligand (sCD40L) levels were determined by a multiplex immunoassay. Anticardiolipin antibodies were evaluated using ELISA assays. Thirty-two frequency-matched plasma/serum samples from healthy donors were used as controls. RESULTS: Levels of IL-6, IP-10, sCD40L, IFN-α and TNF-α were significantly elevated in SLE patients versus controls. There was a positive but moderate correlation between SLAM-R scores at baseline and levels of IFN-α (p = 0.0546). Hydroxychloroquine therapy resulted in a significant decrease in SLAM-R scores (p = 0.0157), and the decrease in SLAM-R after hydroxychloroquine therapy strongly correlated with decreases in IFN-α (p = 0.0087). CONCLUSIONS: Hydroxychloroquine therapy resulted in significant clinical improvement in SLE patients, which strongly correlated with reductions in IFN-α levels. This indicates an important role for the inhibition of endogenous TLR activation in the action of hydroxychloroquine in SLE and provides additional evidence for the importance of type I interferons in the pathogenesis of SLE. This study underscores the use of hydroxychloroquine in the treatment of SLE.


Assuntos
Antirreumáticos/uso terapêutico , Citocinas/sangue , Hidroxicloroquina/uso terapêutico , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Adolescente , Adulto , Antirreumáticos/farmacologia , Biomarcadores/sangue , Ligante de CD40/sangue , Ligante de CD40/efeitos dos fármacos , Quimiocina CCL2/sangue , Quimiocina CCL2/efeitos dos fármacos , Quimiocina CXCL10/sangue , Quimiocina CXCL10/efeitos dos fármacos , Estudos de Coortes , Citocinas/efeitos dos fármacos , Feminino , Humanos , Hidroxicloroquina/farmacologia , Interferon-alfa/sangue , Interferon-alfa/efeitos dos fármacos , Interleucina-1beta/sangue , Interleucina-1beta/efeitos dos fármacos , Interleucina-6/sangue , Interleucina-8/sangue , Interleucina-8/efeitos dos fármacos , Lúpus Eritematoso Sistêmico/etnologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Estados Unidos , Adulto Jovem
10.
Biomicrofluidics ; 16(5): 054106, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36238725

RESUMO

Two approaches of an automatic control were studied through mathematical fitting obtained from color mixing saturation curves in polydimethylsiloxane microfluidic devices: The integrative control with variable integral gain and integrative control with constant integral gain. The aim of this work is to control the color percentage decrement when dye is injected. The results indicate that microfluidic systems are very sensitive to changes in flow and the control variable needs to change slowly; that is, it must be small (at least 100 times less than the theoretically calculated values). The control and stabilization of the microfluidic system were achieved for dye percentages above 60%. The controlling color percentage could provide a tool to regulate other parameters' concentration applied to cell culture and alkalinity control (pH) of solutions in microfluidic devices.

11.
Int J Biol Macromol ; 189: 1-10, 2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34364942

RESUMO

Biosynthesis of bacterial cellulose (BC) in cylindrical oxygen permeable molds allows the production of hollow tubular structures of increasing interest for biomedical applications (artificial blood vessels, ureters, urethra, trachea, esophagus, etc.). In the current contribution a simple set-up is used to obtain BC tubes of predefined dimensions; and the effects of fermentation time on the water holding capacity, nanofibrils network architecture, specific surface area, chemical purity, thermal stability, mechanical properties, and cell adhesion, proliferation and migration of BC tubes are systematically analysed for the first time. The results reported highlight the role of culture time on key properties of the BC tubes produced, with significant differences arising from the denser and more compact fibril arrangements generated at longer fermentation intervals.


Assuntos
Tecnologia Biomédica , Celulose/biossíntese , Fermentação , Gluconacetobacter xylinus/metabolismo , Tecido Adiposo/citologia , Animais , Biomassa , Reatores Biológicos/microbiologia , Células Cultivadas , Celulose/ultraestrutura , Humanos , Masculino , Coelhos , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Células-Tronco/citologia , Suínos , Resistência à Tração , Termodinâmica
12.
Cephalalgia ; 28(3): 216-25, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18254892

RESUMO

There are multiple risk factors for chronic daily headache (CDH), but they are usually assessed in an isolated form without an adequate control for confounders. CDH is considered a variant of episodic headache, but studies have not gathered enough evidence to evaluate simultaneously CDH and episodic in the same population. We set out to establish simultaneously the factors associated with chronic daily or episodic headache in a population setting, using a cross-sectional survey in a random sample of 1505 adult urban inhabitants (Bucaramanga, Colombia). The survey asked questions about headache, family and personal history of disease, and consumption or abuse of caffeine, alcohol, hypnotics and analgesics. The association among independent variables and CDH or episodic headache was made with multinomial logistic regression. Female gender, arterial hypertension or cranial trauma history, and a high score in the depression scale are associated with episodic headache and CDH. Parents with CDH, the complaint of multiple arousals during sleep and use of hypnotics are associated with CDH, but not with episodic headache. Age <36 years, alcoholism and snoring are factors associated only with episodic headache. Chronic daily headache and episodic headache have several common risk factors, but there are other factors not shared by both conditions.


Assuntos
Cefaleia Histamínica/epidemiologia , Transtornos da Cefaleia/epidemiologia , Adolescente , Adulto , Idoso , Cefaleia Histamínica/patologia , Cefaleia Histamínica/psicologia , Colômbia/epidemiologia , Estudos Transversais , Feminino , Transtornos da Cefaleia/patologia , Transtornos da Cefaleia/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores Sexuais
13.
Mol Neurobiol ; 55(6): 4529-4542, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28688003

RESUMO

Behavioral intervention therapy has proven beneficial in the treatment of autism and intellectual disabilities (ID), raising the possibility of certain changes in molecular mechanisms activated by these interventions that may promote learning. Fragile X syndrome (FXS) is a neurodevelopmental disorder characterized by autistic features and intellectual disability and can serve as a model to examine mechanisms that promote learning. FXS results from mutations in the fragile X mental retardation 1 gene (Fmr1) that prevents expression of the Fmr1 protein (FMRP), a messenger RNA (mRNA) translation regulator at synapses. Among many other functions, FMRP organizes a complex with the actin cytoskeleton-regulating small Rho GTPase Rac1. As in humans, Fmr1 KO mice lacking FMRP display autistic-like behaviors and deformities of actin-rich synaptic structures in addition to impaired hippocampal learning and synaptic plasticity. These features have been previously linked to proper function of actin remodeling proteins that includes Rac1. An important step in Rac1 activation and function is its translocation to the membrane, where it can influence synaptic actin cytoskeleton remodeling during hippocampus-dependent learning. Herein, we report that Fmr1 KO mouse hippocampus exhibits increased levels of membrane-bound Rac1, which may prevent proper learning-induced synaptic changes. We also determine that increasing training intensity during fear conditioning (FC) training restores contextual memory in Fmr1 KO mice and reduces membrane-bound Rac1 in Fmr1 KO hippocampus. Increased training intensity also results in normalized long-term potentiation in hippocampal slices taken from Fmr1 KO mice. These results point to interventional treatments providing new therapeutic options for FXS-related cognitive dysfunction.


Assuntos
Actinas/metabolismo , Membrana Celular/metabolismo , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/prevenção & controle , Condicionamento Psicológico , Síndrome do Cromossomo X Frágil/metabolismo , Hipocampo/metabolismo , Animais , Citosol/metabolismo , Medo , Feminino , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Síndrome do Cromossomo X Frágil/fisiopatologia , Hipocampo/crescimento & desenvolvimento , Humanos , Potenciação de Longa Duração , Masculino , Memória , Camundongos Knockout , Ritmo Teta , Quinases Ativadas por p21/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo
14.
Int. j. morphol ; 41(5): 1281-1287, oct. 2023. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1521045

RESUMO

SUMMARY: Osteotechnics is one of the different anatomical preservation techniques and can be defined as the technique designed to prepare, clean, obtain and preserve bone structures that can be used in the teaching, museographic or research field. The osteotechnical technique procedure consists of the following phases: debulk and disjoint, maceration, cooking, cleaning, degreasing, bleaching, and labeling to obtain bone material. Seven phases will be explained in detail, as well as the materials, instruments, quantities of the substances used, and the time required to obtain human bone material. We consider that this article can serve as a guide, given that all the experimentation was carried out with human biological material. This methodological proposal could be consolidated and established based on the experience acquired during the creation of the contemporary skeletal collection of the department of innovation in human biological material (DIMBIH). Therefore, the purpose of our proposal is to provide tools that facilitate the work of those who carry out this work and fundamentally to avoid irreversible or irreparable damage to the osteological material, since it is of great value and difficult to acquire for disciplines as anatomy, veterinary, physical and forensic anthropology, medicine, dentistry and biology.


La osteotecnia es una de las técnicas diferentes de conservación anatómica y puede definirse como la técnica destinada a preparar, limpiar, obtener y conservar estructuras óseas que pueden ser utilizadas en el ámbito docente, museográfico o de investigación. El procedimiento de la técnica osteotécnica consta de las siguientes fases: descarnado y desarticulado, maceración, cocción, limpieza, desengrase, blanqueo y marcaje para la obtención de material óseo. Se explicarán en detalle siete fases, así como los materiales, instrumentos, cantidades de las sustancias utilizadas y el tiempo necesario para obtener material óseo humano. Consideramos que este artículo puede servir de guía, dado que toda la experimentación se realizó con material biológico humano. Esta propuesta metodológica pudo consolidarse y establecerse a partir de la experiencia adquirida durante la creación de la colección esquelética contemporánea del Departamento de Innovación en Material Biológico Humano (DIMBIH). Por lo tanto, el propósito de nuestra propuesta es brindar herramientas que faciliten el trabajo de quienes realizan este trabajo y fundamentalmente evitar daños irreversibles o irreparables en el material osteológico, ya que es de gran valor y difícil adquisición para las disciplinas como la anatomía, veterinaria, antropología física y forense, medicina, odontología y biología.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Preservação Biológica/métodos , Osso e Ossos , Anatomia/métodos , Antropologia Física , Osteologia
15.
Bioresour Technol ; 249: 439-446, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29065326

RESUMO

Approximately 1 million tons of agave plants are processed annually by the Mexican tequila and mezcal industry, generating vast amounts of agroindustrial solid waste. This type of lignocellulosic biomass is considered to be agroindustrial residue, which can be used to produce enzymes, giving it added value. However, the structure of lignocellulosic biomass makes it highly recalcitrant, and results in relatively low yield when used in its native form. The aim of this study was to investigate an effective pre-treatment method for the production of commercially important hydrolytic enzymes. In this work, the physical and chemical modification of Agave durangensis leaves was analysed using ultrasound and high temperature as pre-treatments, and production of enzymes was evaluated. The pre-treatments resulted in modification of the lignocellulosic structure and composition; the ultrasound pre-treatment improved the production of inulinase by 4 U/mg and cellulase by 0.297 U/mg, and thermal pre-treatment improved ß-fructofuranosidase by 30 U/mg.


Assuntos
Agave , beta-Frutofuranosidase , Celulase , Hidrólise , Folhas de Planta
16.
Virusdisease ; 28(1): 102-110, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28466061

RESUMO

This is a first report in Mexico of the presence of antibodies against respiratory syncytial virus (RSV) and parainfluenza-3 virus in Mexican sheep in different productive stages. We determine the association of serological positivity with age and production system, and obtain molecular evidence of infection by both virus. RSV prevalence in adult sheep was 47% (49/105) at the tropic and 64% (63/99) at the uplands. A significant difference in RSV seropositivity between animals from the tropic and the uplands was observed (P < 0.05). Seropositivity correlated with production system (P = 0.003, OR = 2.042), with a risk of showing antibodies was 2.042 times higher in sheep under an extensive production system. A significant difference in PI3V seropositivity between animals from either provenance (P = 0.017, OR = 0.475) were also found, with a risk of showing antibodies 0.475 times higher in sheep under an extensive production system. Genetic material from RSV and PI3V was identified by RT-PCR in nasal swab samples from clinically healthy lambs and confirmed by sequencing and phylogenetic analysis. Serological results show that sheep are susceptible to infection by both viruses, and molecular results suggest that the identified antibodies are result of natural infections and reinfections.

17.
Cancer Res ; 61(14): 5652-9, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11454720

RESUMO

Metastases from prostatic adenocarcinoma (prostate cancer) are characterized by their predilection for bone and typical osteoblastic features. An in vitro model of bone metastases from prostate cancer was developed using a bicompartment coculture system of mouse osteoblasts and human prostate cancer cells. In this model, the bone-derived prostate cancer cell lines MDA PCa 2a and MDA PCa 2b induced a specific and reproducible increase in osteoblast proliferation. Moreover, these cells were able to induce osteoblast differentiation, as assessed by increased alkaline phosphatase activity, Osteocalcin expression, and calcified matrix formation. This osteoblastic reaction was confirmed in vivo by intrafemoral injection of MDA PCa 2b cells into severe combined immunodeficiency disease mice. In contrast, the highly undifferentiated, bone-derived human prostate cancer cell line PC3 did not produce an osteoblastic reaction in vitro and induced osteolytic lesions in vivo. The osteoblast differentiation induced by MDA PCa 2b cells was associated with up-regulation of the osteoblast-specific transcriptor factor Cbfa1. Moreover, treatment of osteoblasts with conditioned medium obtained from MDA PCa 2b cells resulted in up-regulation of Cbfa1 and Osteocalcin expression. In support of the differentiation studies, a microarray analysis showed that primary mouse osteoblasts grown in the presence of MDA PCa 2b cells showed a shift in the pattern of gene expression with an increase in mRNA-encoding Procollagen type I and Osteopontin and a decrease in mRNA-encoding proteins associated with myoblast differentiation, namely myoglobin and myosin light-chain 2. Taken together, these findings suggest that the bone-derived prostate cancer cells MDA PCa 2a and MDA PCa 2b promote differentiation of osteoblast precursors to an osteoblastic phenotype through a Cbfa1-dependent pathway. These results also established that soluble factors produced by prostate cancer cells can induce expression of osteoblast-specific genes. This in vitro model provides a valuable system to isolate molecules secreted by prostate cancer cells that favor osteoblast differentiation. Moreover, it allows to screen for therapeutic agents blocking the osteoblast response to prostate cancer.


Assuntos
Diferenciação Celular , Proteínas de Neoplasias , Osteoblastos/metabolismo , Neoplasias da Próstata/patologia , Fatores de Transcrição/fisiologia , Animais , Northern Blotting , Osso e Ossos/patologia , Contagem de Células , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Subunidade alfa 1 de Fator de Ligação ao Core , Meios de Cultivo Condicionados/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos SCID , Transplante de Neoplasias , Osteoblastos/citologia , Osteocalcina/genética , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/fisiopatologia , RNA/genética , RNA/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , Transplante Heterólogo , Células Tumorais Cultivadas
18.
Arch Soc Esp Oftalmol ; 91(3): 125-9, 2016 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26718223

RESUMO

OBJECTIVE: To determine the number of hypotensive drugs required to control the intraocular pressure (IOP) in patients with primary open angle glaucoma (POAG) and diabetes mellitus (DM), as well as describing their demographic characteristics. DESIGN: Observational, cross-sectional, and descriptive study. METHODS: Twenty four patients (47 eyes) with definitive diagnosis of DM and POAG were included for a six month follow up, recording demographic data and IOP control. RESULTS: The mean age was 67.04±8.9 years, and 79% of patients were female. Mean time from diagnosis of DM was 13.87 years, and 6.21 years for POAG. No statistical difference was observed between initial and final visual acuity (P = 0.49). There was a statistical difference between initial and final IOP once treatment was started (P = 0.002), requiring 1.9 hypotensive drugs (P < 0.05). Beta-blockers were the most used hypotensive drugs for the initial (41%), as well as the final IOP control medication (28%). CONCLUSION: The mean IOP in patients with DM and POAG was 16.8 mmHg, with the use of 1.9 hypotensive drugs.


Assuntos
Diabetes Mellitus/classificação , Glaucoma de Ângulo Aberto/complicações , Pressão Intraocular , Idoso , Estudos Transversais , Feminino , Glaucoma de Ângulo Aberto/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Tonometria Ocular
19.
Oncogene ; 18(2): 397-406, 1999 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-9927196

RESUMO

Differentiation of cells is typically marked by a cessation of proliferation with a concurrent entrance into a distinct metabolic state marked by tissue specific gene expression. The mechanism by which the cell exits the cell cycle in this process is poorly understood. To determine the potential roles of the cell cycle machinery in the regulation of the terminal differentiation process of epidermal cells, we selected a well characterized in vitro model in which primary mouse keratinocytes are induced to differentiate in response to a raised calcium ion concentration in the medium. The withdrawal from the cell cycle correlates very well with a number of changes in the cell cycle machinery. Changes in the phosphorylation status of the Rb family of proteins occurs coordinately with an increased association of p21, p27 and p57 with cdk2. Furthermore, we find that inhibition of cdk2 activity is not sufficient to elicit changes that occur during keratinocyte differentiation. Finally, the previously described v-Ha-ras block of keratinocyte differentiation correlates with altered regulation of both cyclin D1 and cdk2 suggesting that these genes may play a role in the Ha-ras transformation of a keratinocyte.


Assuntos
Ciclo Celular , Diferenciação Celular , Queratinócitos/citologia , Animais , Células Cultivadas , Quinases Ciclina-Dependentes/antagonistas & inibidores , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/metabolismo , Queratinócitos/enzimologia , Queratinócitos/metabolismo , Camundongos , Proteína Oncogênica p21(ras)/metabolismo , Fosforilação
20.
Oncogene ; 16(15): 1913-20, 1998 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-9591774

RESUMO

Deregulated expression of cyclin D1 has been found in several types of human tumors. In order to investigate factors involved in human prostate cancer progression, we studied the effects of cyclin D1 overexpression on human prostate cancer cell proliferation and tumorigenicity by transfecting LNCaP cells with a retroviral vector containing human cyclin D1 cDNA. When compared to the parental and control-vector transfected LNCaP cells, these cyclin D1-transfected cells had more cells in S-phase and lower growth factor requirements. Furthermore, these cells grew more in androgen-free medium. We also detected higher levels of Rb phosphorylation and E2F-1 protein levels in LNCaP/cyclin D1 cells than that in the parental and vector control cells in medium with or without androgen. Cyclin D1 transfected clones formed tumors more rapidly than control and parental cells. These tumors were refractory to the androgen-ablation treatment by castration, whereas tumors from parental and vector-control LNCaP cells regressed within 4 weeks after castration. These results suggest that overexpression of cyclin D1 changes the growth properties, increases tumorigenicity and decreases the requirement for androgen stimulation in LNCaP cells both in vitro and in vivo.


Assuntos
Ciclina D1/fisiologia , Neoplasias da Próstata/patologia , Androgênios/farmacologia , Animais , Divisão Celular , Ciclina D1/genética , Humanos , Masculino , Camundongos , Camundongos Nus , Neoplasias da Próstata/etiologia , RNA Mensageiro/análise , Células Tumorais Cultivadas
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