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1.
BMC Biol ; 20(1): 295, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36575431

RESUMO

BACKGROUND: Laterality in relation to behavior and sensory systems is found commonly in a variety of animal taxa. Despite the advantages conferred by laterality (e.g., the startle response and complex motor activities), little is known about the evolution of laterality and its plasticity in response to ecological demands. In the present study, a comparative study model, the Mexican tetra (Astyanax mexicanus), composed of two morphotypes, i.e., riverine surface fish and cave-dwelling cavefish, was used to address the relationship between environment and laterality. RESULTS: The use of a machine learning-based fish posture detection system and sensory ablation revealed that the left cranial lateral line significantly supports one type of foraging behavior, i.e., vibration attraction behavior, in one cave population. Additionally, left-right asymmetric approaches toward a vibrating rod became symmetrical after fasting in one cave population but not in the other populations. CONCLUSION: Based on these findings, we propose a model explaining how the observed sensory laterality and behavioral shift could help adaptation in terms of the tradeoff in energy gain and loss during foraging according to differences in food availability among caves.


Assuntos
Cavernas , Characidae , Animais , Evolução Biológica , Characidae/fisiologia , Comportamento Animal/fisiologia , Órgãos dos Sentidos
2.
Dev Biol ; 441(2): 262-271, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-29782817

RESUMO

Many animal species exhibit laterality in sensation and behavioral responses, namely, the preference for using either the left or right side of the sensory system. For example, some fish use their left eye when observing social stimuli, whereas they use their right eye to observe novel objects. However, it is largely unknown whether such laterality in sensory-behavior coupling evolves during rapid adaptation processes. Here, in the Mexican tetra, Astyanax mexicanus, we investigate the laterality in the relationship between an evolved adaptive behavior, vibration attraction behavior (VAB), and its main sensors, mechanosensory neuromasts. A. mexicanus has a surface-dwelling form and cave-dwelling forms (cavefish), whereby a surface fish ancestor colonized the new environment of a cave, eventually evolving cave-type morphologies such as increased numbers of neuromasts at the cranium. These neuromasts are known to regulate VAB, and it is known that, in teleosts, the budding (increasing) process of neuromasts is accompanied with dermal bone formation. This bone formation is largely regulated by endothelin signaling. To assess the evolutionary relationship between bone formation, neuromast budding, and VAB, we treated 1-3 month old juvenile fish with endothelin receptor antagonists. This treatment significantly increased cranial neuromasts in both surface and cavefish, and the effect was significantly more pronounced in cavefish. Antagonist treatment also increased the size of dermal bones in cavefish, but neuromast enhancement was observed earlier than dermal bone formation, suggesting that endothelin signaling may independently regulate neuromast development and bone formation. In addition, although we did not detect a major change in VAB level under this antagonist treatment, cavefish did show a positive correlation of VAB with the number of neuromasts on their left side but not their right. This laterality in correlation was observed when VAB emerged during cavefish development, but it was not seen in surface fish under any conditions tested, suggesting this laterality emerged through an evolutionary process. Above all, cavefish showed higher developmental plasticity in neuromast number and bone formation, and they showed an asymmetric correlation between the number of left-right neuromasts and VAB.


Assuntos
Evolução Biológica , Caraciformes/embriologia , Comportamento Alimentar/fisiologia , Mecanotransdução Celular/fisiologia , Osteogênese/fisiologia , Crânio/embriologia , Animais , Endotelinas/metabolismo , Proteínas de Peixes/agonistas , Proteínas de Peixes/metabolismo , Receptores de Endotelina/agonistas , Receptores de Endotelina/metabolismo
3.
Proc Natl Acad Sci U S A ; 113(26): 7136-41, 2016 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-27298375

RESUMO

The breakdown of plant cell wall (PCW) glycans is an important biological and industrial process. Noncatalytic carbohydrate binding modules (CBMs) fulfill a critical targeting function in PCW depolymerization. Defining the portfolio of CBMs, the CBMome, of a PCW degrading system is central to understanding the mechanisms by which microbes depolymerize their target substrates. Ruminococcus flavefaciens, a major PCW degrading bacterium, assembles its catalytic apparatus into a large multienzyme complex, the cellulosome. Significantly, bioinformatic analyses of the R. flavefaciens cellulosome failed to identify a CBM predicted to bind to crystalline cellulose, a key feature of the CBMome of other PCW degrading systems. Here, high throughput screening of 177 protein modules of unknown function was used to determine the complete CBMome of R. flavefaciens The data identified six previously unidentified CBM families that targeted ß-glucans, ß-mannans, and the pectic polysaccharide homogalacturonan. The crystal structures of four CBMs, in conjunction with site-directed mutagenesis, provide insight into the mechanism of ligand recognition. In the CBMs that recognize ß-glucans and ß-mannans, differences in the conformation of conserved aromatic residues had a significant impact on the topology of the ligand binding cleft and thus ligand specificity. A cluster of basic residues in CBM77 confers calcium-independent recognition of homogalacturonan, indicating that the carboxylates of galacturonic acid are key specificity determinants. This report shows that the extended repertoire of proteins in the cellulosome of R. flavefaciens contributes to an extended CBMome that supports efficient PCW degradation in the absence of CBMs that specifically target crystalline cellulose.


Assuntos
Proteínas de Bactérias/metabolismo , Celulossomas/metabolismo , Polissacarídeos/metabolismo , Ruminococcus/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Celulossomas/química , Celulossomas/genética , Cristalografia por Raios X , Modelos Moleculares , Polissacarídeos/química , Ligação Proteica , Ruminococcus/química , Ruminococcus/genética
4.
Microb Cell Fact ; 16(1): 4, 2017 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-28093085

RESUMO

BACKGROUND: Animal venoms are large, complex libraries of bioactive, disulphide-rich peptides. These peptides, and their novel biological activities, are of increasing pharmacological and therapeutic importance. However, recombinant expression of venom peptides in Escherichia coli remains difficult due to the significant number of cysteine residues requiring effective post-translational processing. There is also an urgent need to develop high-throughput recombinant protocols applicable to the production of reticulated peptides to enable efficient screening of their drug potential. Here, a comprehensive study was developed to investigate how synthetic gene design, choice of fusion tag, compartment of expression, tag removal conditions and protease recognition site affect levels of solubility of oxidized venom peptides produced in E. coli. RESULTS: The data revealed that expression of venom peptides imposes significant pressure on cysteine codon selection. DsbC was the best fusion tag for venom peptide expression, in particular when the fusion was directed to the bacterial periplasm. While the redox activity of DsbC was not essential to maximize expression of recombinant fusion proteins, redox activity did lead to higher levels of correctly folded target peptides. With the exception of proline, the canonical TEV protease recognition site tolerated all other residues at its C-terminus, confirming that no non-native residues, which might affect activity, need to be incorporated at the N-terminus of recombinant peptides for tag removal. CONCLUSIONS: This study reveals that E. coli is a convenient heterologous host for the expression of soluble and functional venom peptides. Using the optimal construct design, a large and diverse range of animal venom peptides were produced in the µM scale. These results open up new possibilities for the high-throughput production of recombinant disulphide-rich peptides in E. coli.


Assuntos
Endopeptidases/metabolismo , Escherichia coli/genética , Biossíntese Peptídica , Peptídeos/genética , Peçonhas/biossíntese , Peçonhas/genética , Animais , Biotecnologia/métodos , Clonagem Molecular , Dissulfetos/química , Endopeptidases/química , Vetores Genéticos , Ensaios de Triagem em Larga Escala , Oxirredução , Peptídeos/química , Peptídeos/isolamento & purificação , Periplasma/química , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/isolamento & purificação , Solubilidade , Peçonhas/química , Peçonhas/metabolismo
5.
PLoS One ; 19(5): e0300793, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38748713

RESUMO

In nature, animals must navigate to forage according to their sensory inputs. Different species use different sensory modalities to locate food efficiently. For teleosts, food emits visual, mechanical, chemical, and/or possibly weak-electrical signals, which can be detected by optic, auditory/lateral line, and olfactory/taste buds sensory systems. However, how fish respond to and use different sensory inputs when locating food, as well as the evolution of these sensory modalities, remain unclear. We examined the Mexican tetra, Astyanax mexicanus, which is composed of two different morphs: a sighted riverine (surface fish) and a blind cave morph (cavefish). Compared with surface fish, cavefish have enhanced non-visual sensory systems, including the mechanosensory lateral line system, chemical sensors comprising the olfactory system and taste buds, and the auditory system to help navigate toward food sources. We tested how visual, chemical, and mechanical stimuli evoke food-seeking behavior. In contrast to our expectations, both surface fish and cavefish did not follow a gradient of chemical stimulus (food extract) but used it as a cue for the ambient existence of food. Surface fish followed visual cues (red plastic beads and food pellets), but, in the dark, were likely to rely on mechanosensors-the lateral line and/or tactile sensor-as cavefish did. Our results indicate cavefish used a similar sensory modality to surface fish in the dark, while affinity levels to stimuli were higher in cavefish. In addition, cavefish evolved an extended circling strategy to forage, which may yield a higher chance to capture food by swimming-by the food multiple times instead of once through zigzag motion. In summary, we propose that ancestors of cavefish, similar to the modern surface fish, evolved extended food-seeking behaviors, including circling motion, to adapt to the dark.


Assuntos
Characidae , Comportamento Alimentar , Animais , Comportamento Alimentar/fisiologia , Characidae/fisiologia , Evolução Biológica , Cavernas , Sinais (Psicologia) , Cegueira/fisiopatologia
6.
bioRxiv ; 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37398421

RESUMO

In nature, animals must navigate to forage according to their sensory inputs. Different species use different sensory modalities to locate food efficiently. For teleosts, food emits visual, mechanical, chemical, and/or possibly weak-electrical signals, which can be detected by optic, auditory/lateral line, and olfactory/taste buds sensory systems. However, how fish respond to and use different sensory inputs when locating food, as well as the evolution of these sensory modalities, remain unclear. We examined the Mexican tetra, Astyanax mexicanus, which is composed of two different morphs: a sighted riverine (surface fish) and a blind cave morph (cavefish). Compared with surface fish, cavefish have enhanced non-visual sensory systems, including the mechanosensory lateral line system, chemical sensors comprising the olfactory system and taste buds, and the auditory system to help navigate toward food sources. We tested how visual, chemical, and mechanical stimuli evoke food-seeking behavior. In contrast to our expectations, both surface fish and cavefish did not follow a gradient of chemical stimulus (food extract) but used it as a cue for the ambient existence of food. Surface fish followed visual cues (red plastic beads and food pellets), but, in the dark, were likely to rely on mechanosensors-the lateral line and/or tactile sensor-as cavefish did. Our results indicate cavefish used similar sensory modality to surface fish in the dark, while adherence levels to stimuli were higher in cavefish. In addition, cavefish evolved an extended circling strategy to capture food, which may yield a higher chance to capture food by swimming-by the food multiple times instead of once through zigzag motion. In summary, we propose ancestors of cavefish similar to surface fish may have needed little modification in food-seeking strategy to adapt to the dark.

7.
Life (Basel) ; 13(2)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36836922

RESUMO

Hypersensitivity pneumonitis is a complex interstitial lung syndrome and is associated with significant morbimortality, particularly for fibrotic disease. This condition is characterized by sensitization to a specific antigen, whose early identification is associated with improved outcomes. Biomarkers measure objectively biologic processes and may support clinical decisions. These tools evolved to play a crucial role in the diagnosis and management of a wide range of human diseases. This is not the case, however, with hypersensitivity pneumonitis, where there is still great room for research in the path to find consensual diagnostic biomarkers. Gaps in the current evidence include lack of validation, validation against healthy controls alone, small sampling and heterogeneity in diagnostic and classification criteria. Furthermore, discriminatory accuracy is currently limited by overlapping mechanisms of inflammation, damage and fibrogenesis between ILDs. Still, biomarkers such as BAL lymphocyte counts and specific serum IgGs made their way into clinical guidelines, while others including KL-6, SP-D, YKL-40 and apolipoproteins have shown promising results in leading centers and have potential to translate into daily practice. As research proceeds, it is expected that the emergence of novel categories of biomarkers will offer new and thriving tools that could complement those currently available.

8.
Case Rep Pediatr ; 2023: 6686511, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37790920

RESUMO

Background: Ring chromosome 17 syndrome is a rare hereditary disorder whose prevalence is less than 1 : 1.000.000. We present a ten-year-old patient with ring chromosome 17 syndrome who had short stature and was treated with recombinant human growth hormone (rhGH). Case Report. A ten-year-old male scholar had moderate left conductive deafness, left kidney hypoplasia with hypertension, epilepsy, malformations in hands, feet, and abdomen, and disproportionately short stature. Despite no evidence of growth hormone deficiency, rhGH treatment was indicated as a therapeutic test due to his decelerated growth velocity and severe short stature. As a result, his growth velocity increased by 4.2 cm per year and his stature Z-score increased (from -5.87 to -5.23). Conclusion: The patient's severe short stature may be related to genetic, environmental, and hormonal factors and the positive response to rhGH may indicate abnormalities in the somatotropic axis that were mitigated with the treatment. Although rhGH associated with adequate comorbidities controls improved his growth velocity and height Z-score, its effects in the long term are still unclear.

9.
Appl Environ Microbiol ; 78(14): 4781-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22562994

RESUMO

In general, cellulases and hemicellulases are modular enzymes in which the catalytic domain is appended to one or more noncatalytic carbohydrate binding modules (CBMs). CBMs, by concentrating the parental enzyme at their target polysaccharide, increase the capacity of the catalytic module to bind the substrate, leading to a potentiation in catalysis. Clostridium thermocellum hypothetical protein Cthe_0821, defined here as C. thermocellum Man5A, is a modular protein comprising an N-terminal signal peptide, a family 5 glycoside hydrolase (GH5) catalytic module, a family 32 CBM (CBM32), and a C-terminal type I dockerin module. Recent proteomic studies revealed that Cthe_0821 is one of the major cellulosomal enzymes when C. thermocellum is cultured on cellulose. Here we show that the GH5 catalytic module of Cthe_0821 displays endomannanase activity. C. thermocellum Man5A hydrolyzes soluble konjac glucomannan, soluble carob galactomannan, and insoluble ivory nut mannan but does not attack the highly galactosylated mannan from guar gum, suggesting that the enzyme prefers unsubstituted ß-1,4-mannoside linkages. The CBM32 of C. thermocellum Man5A displays a preference for the nonreducing ends of mannooligosaccharides, although the protein module exhibits measurable affinity for the termini of ß-1,4-linked glucooligosaccharides such as cellobiose. CBM32 potentiates the activity of C. thermocellum Man5A against insoluble mannans but has no significant effect on the capacity of the enzyme to hydrolyze soluble galactomannans and glucomannans. The product profile of C. thermocellum Man5A is affected by the presence of CBM32.


Assuntos
Clostridium thermocellum/enzimologia , Mananas/metabolismo , Manosidases/metabolismo , Sequência de Aminoácidos , Carboidratos/química , Clostridium thermocellum/química , Clostridium thermocellum/genética , Escherichia coli/enzimologia , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Galactanos/metabolismo , Glicosídeo Hidrolases/metabolismo , Manosidases/química , Manosidases/genética , Dados de Sequência Molecular , Gomas Vegetais/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidade por Substrato
10.
Artigo em Inglês | MEDLINE | ID: mdl-35140187

RESUMO

SUMMARY: We describe a rare case of a girl with an initial diagnostic hypothesis of chromosome 8 trisomy based on clinical findings and karyotyping, which identified a structural change in the short arm of chromosome 8 (46,XX,add(8)(p23)). At the age of 7, she developed type 1 diabetes mellitus and started insulin therapy with multiple daily doses, and then she started to use a continuous insulin infusion system (pump) at 10 years of age. At the age of 12, she underwent a molecular study that identified an unbalanced translocation between the short arms of chromosomes 6 and 8 - 46,XX,add(8)(p23).ish der(8)t(6;8)(GS-196I5+;RP-11338B22-). LEARNING POINTS: Patients with an unbalanced translocation between the short arms of chromosomes 6 and 8 - 46,XX,add(8)(p23).ish der(8)t(6;8)(GS-196I5+;RP-11338B22-) may present syndromic features suggestive of chromosome 8 trisomy. Main characteristics are a prominent forehead, ocular and breast hypertelorism, ocular, external ear and palate abnormalities, a short neck, heart defects, and developmental delay. Patients with 46,XX,add(8)(p23).ish der(8)t(6;8)(GS-196I5+;RP-11338B22-) may present autoimmune type 1 diabetes mellitus. Karyotyping is an essential tool for the diagnosis of chromosomal changes, but it has some limitations. Multiplex ligation-dependent probe amplification, array-single nucleotide polymorphism and fluorescence in situ hybridization can help diagnose genetic syndromes in patients with atypical evolution.

11.
Rev Paul Pediatr ; 40: e2020407, 2021.
Artigo em Inglês, Português | MEDLINE | ID: mdl-34614139

RESUMO

OBJECTIVE: To evaluate sleep characteristics of children and adolescents with type 1 diabetes mellitus (T1DM) and their relationship with glycemic control. METHODS: A cross-sectional study was conducted at a public hospital in São Paulo, Brazil. It included 86 patients with T1DM, aged between 10 and 18 years old, who were on insulin therapy, had performed at least three measurements of capillary blood glucose throughout the day, and had normal thyroid function. The clinical, anthropometric, and laboratory data of each patient were evaluated. The Pediatric Daytime Sleepiness Scale (PDSS) and the Munich Chronotype Questionnaire (MCTQ) were used to assess the sleep characteristics. RESULTS: The mean level of glycated hemoglobin (HbA1c) was 9.2±2.1%, and it was higher in adolescents than in children. The mean score of PDSS was 13.9±4.7. Patients with HbA1c<7.5% had lower PDSS scores and longer sleep duration on weekdays than patients with HbA1c≥7.5%. HbA1c levels were negatively correlated with chronotype values and sleep duration on weekdays and positively correlated with social jet lag. Patients who had had T1DM for less than three years had a higher prevalence of daytime sleepiness. The regression analysis showed that higher HbA1c (≥7.5%) and shorter time since the diagnosis of T1DM increased the chance of daytime sleepiness, regardless of age and sex. CONCLUSIONS: Patients with higher HbA1c had more daytime sleepiness, a morning chronotype, shorter sleep duration on weekdays and a more significant social jet lag. The shorter diagnosis time for T1DM and greater levels of HbA1c increased the chance of daytime sleepiness.


Assuntos
Diabetes Mellitus Tipo 1 , Distúrbios do Sono por Sonolência Excessiva , Adolescente , Brasil , Criança , Estudos Transversais , Humanos , Sono , Inquéritos e Questionários
12.
Arch Endocrinol Metab ; 65(5): 562-569, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33939908

RESUMO

OBJECTIVE: People with Down's syndrome (DS) have a higher risk of developing type 1 diabetes mellitus (T1D) and may have specific clinical features compared to T1D patients without DS. This study evaluated the clinical and laboratory aspects of T1D in children and adolescents with DS in an admixed population. METHODS: A case-control study comparing patients with T1D and DS (T1D+DS) to patients with T1D without DS (T1D controls) from two tertiary academic Hospitals in São Paulo, Brazil. RESULTS: The sample consisted of 9 patients with T1D+DS and 18 T1D age and sex-matched controls. Anti-glutamic acid decarboxylase 65 antibodies were positive in 7/7 of the 9 T1D+DS patients, confirming the presence of diabetes autoimmunity in this group. Mean age at diagnosis of T1D was 4.9 ± 3.9 years in the T1D+DS group and 6.4 years ± 3 in the T1D control group; early diagnosis (<2 years old) occurred in three T1D+DS patients but only in one T1D control patients, both suggesting lower age of diagnosis in T1D+DS group, although without statistical significance (p = 0.282 and p = 0.093, respectively). The T1D+DS group presented lower total insulin dose (0.7 IU/kg/day ± 0.2) and HbA1c (7.2% ± 0.6) than the control group (1.0 IU/kg/day ± 0.3 and 9.1% ± 0.7, respectively) (p = 0.022 and p = 0.047, respectively). CONCLUSION: We confirmed the autoimmune etiology of diabetes in people with DS in this admixed population. T1D+DS patients developed diabetes earlier and achieved better metabolic control with a lower insulin dose than T1D controls. These findings are in agreement with previous studies in Caucasian populations.


Assuntos
Diabetes Mellitus Tipo 1 , Síndrome de Down , Adolescente , Autoimunidade , Brasil/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/epidemiologia , Síndrome de Down/complicações , Humanos
13.
Biochemistry ; 49(29): 6193-205, 2010 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-20496884

RESUMO

The deconstruction of the plant cell wall is an important biological process that is attracting considerable industrial interest, particularly in the bioenergy sector. Enzymes that attack the plant cell wall generally contain one or more noncatalytic carbohydrate binding modules (CBMs) that play an important targeting function. While CBMs that bind to the backbones of plant structural polysaccharides have been widely described, modules that recognize components of the vast array of decorations displayed on these polymers have been relatively unexplored. Here we show that a family 35 CBM member (CBM35), designated CtCBM35-Gal, binds to alpha-D-galactose (Gal) and, within the context of the plant cell wall, targets the alpha-1,6-Gal residues of galactomannan but not the beta-D-Gal residues in xyloglucan. The crystal structure of CtCBM35-Gal reveals a canonical beta-sandwich fold. Site-directed mutagenesis studies showed that the ligand is accommodated within the loops that connect the two beta-sheets. Although the ligand binding site of the CBM displays significant structural similarity with calcium-dependent CBM35s that target uronic acids, subtle differences in the conformation of conserved residues in the ligand binding site lead to the loss of metal binding and uronate recognition. A model is proposed in which the orientation of the pair of aromatic residues that interact with the two faces of the Gal pyranose ring plays a pivotal role in orientating the axial O4 atom of the ligand toward Asn140, which is invariant in CBM35. The ligand recognition site of exo-CBM35s (CBM35-Gal and the uronic acid binding CBM35s) appears to overlap with that of CBM35-Man, which binds to the internal regions of mannan, a beta-polymer of mannose. Using site-directed mutagenesis, we show that although there is conservation of several functional residues within the binding sites of endo- and exo-CBM35s, the endo-CBM does not utilize Asn113 (equivalent to Asn140 in CBM35-Gal) in mannan binding, despite the importance of the equivalent residue in ligand recognition across the CBM35 and CBM6 landscape. The data presented in this report are placed within a wider phylogenetic context for the CBM35 family.


Assuntos
Proteínas de Bactérias/química , Clostridium thermocellum/enzimologia , Galactose/química , Mananas/química , Sequência de Aminoácidos , Proteínas de Bactérias/classificação , Proteínas de Bactérias/genética , Domínio Catalítico , Parede Celular/química , Cristalografia por Raios X , Ligantes , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Filogenia , Plantas/química , Estrutura Secundária de Proteína
14.
Clin Endocrinol (Oxf) ; 73(6): 700-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20846292

RESUMO

BACKGROUND: Congenital adrenal hyperplasia caused by classic 21-hydroxylase deficiency (21OHD) is an autosomal recessive disorder with a high prevalence of asymptomatic heterozygote carriers (HTZ) in the general population, making case detection desirable by routine methodology. HTZ for classic and nonclassic (NC) forms have basal and ACTH-stimulated values of 17-hydroxyprogesterone (17OHP) that fail to discriminate them from the general population. 21-Deoxycortisol (21DF), an 11-hydroxylated derivative of 17OHP, is an alternative approach to identify 21OHD HTZ. OBJECTIVE: To determine the discriminating value of basal and ACTH-stimulated serum levels of 21DF in comparison with 17OHP in a population of HTZ for 21OHD (n = 60), as well as in NC patients (n = 16) and in genotypically normal control subjects (CS, n = 30), using fourth generation tandem mass spectrometry after HPLC separation (LC-MS/MS). RESULTS: Basal 21DF levels were not different between HTZ and CS, but stimulated values were increased in the former and virtually nonresponsive in CS. Only 17·7% of the ACTH-stimulated 21DF levels overlapped with CS, when compared to 46·8% for 17OHP. For 100% specificity, the sensitivities achieved for ACTH-stimulated 21DF, 17OHP and the quotient [(21DF + 17OHP)/F] were 82·3%, 53·2% and 87%, using cut-offs of 40, 300 ng/dl and 46 (unitless), respectively. Similar to 17OHP, ACTH-stimulated 21DF levels did not overlap between HTZ and NC patients. A positive and highly significant correlation (r = 0·846; P < 0·001) was observed between 21DF and 17OHP pairs of values from NC and HTZ. CONCLUSION: This study confirms the superiority of ACTH-stimulated 21DF, when compared to 17OHP, both measured by LC-MS/MS, in identifying carriers for 21OHD. Serum 21DF is a useful tool in genetic counselling to screen carriers among relatives in families with affected subjects, giving support to molecular results.


Assuntos
Hiperplasia Suprarrenal Congênita/sangue , Hiperplasia Suprarrenal Congênita/diagnóstico , Hormônio Adrenocorticotrópico/química , Cortodoxona/sangue , Triagem de Portadores Genéticos/métodos , Esteroide 21-Hidroxilase/genética , Adolescente , Hiperplasia Suprarrenal Congênita/genética , Adulto , Criança , Pré-Escolar , Cromatografia Líquida , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Espectrometria de Massas em Tandem , Adulto Jovem
15.
Biochem J ; 424(3): 375-84, 2009 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-19758121

RESUMO

Cellulosomes, synthesized by anaerobic microorganisms such as Clostridium thermocellum, are remarkably complex nanomachines that efficiently degrade plant cell wall polysaccharides. Cellulosome assembly results from the interaction of type I dockerin domains, present on the catalytic subunits, and the cohesin domains of a large non-catalytic integrating protein that acts as a molecular scaffold. In general, type I dockerins contain two distinct cohesin-binding interfaces that appear to display identical ligand specificities. Inspection of the C. thermocellum genome reveals 72 dockerin-containing proteins. In four of these proteins, Cthe_0258, Cthe_0435, Cthe_0624 and Cthe_0918, there are significant differences in the residues that comprise the two cohesin-binding sites of the type I dockerin domains. In addition, a protein of unknown function (Cthe_0452), containing a C-terminal cohesin highly similar to the equivalent domains present in C. thermocellum-integrating protein (CipA), was also identified. In the present study, the ligand specificities of the newly identified cohesin and dockerin domains are described. The results revealed that Cthe_0452 is located at the C. thermocellum cell surface and thus the protein was renamed as OlpC. The dockerins of Cthe_0258 and Cthe_0435 recognize, preferentially, the OlpC cohesin and thus these enzymes are believed to be predominantly located at the surface of the bacterium. By contrast, the dockerin domains of Cthe_0624 and Cthe_0918 are primarily cellulosomal since they bind preferentially to the cohesins of CipA. OlpC, which is a relatively abundant protein, may also adopt a 'warehouse' function by transiently retaining cellulosomal enzymes at the cell surface before they are assembled on to the multienzyme complex.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Clostridium thermocellum/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Sítios de Ligação , Proteínas de Transporte/química , Proteínas de Transporte/genética , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Parede Celular/metabolismo , Celulossomas/metabolismo , Proteínas Cromossômicas não Histona/química , Proteínas Cromossômicas não Histona/genética , Clostridium thermocellum/genética , Eletroforese em Gel de Poliacrilamida , Cinética , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Mutação , Ligação Proteica , Homologia de Sequência de Aminoácidos , Termodinâmica , Coesinas
16.
Int J Surg Case Rep ; 77: 799-802, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33395899

RESUMO

INTRODUCTION: Chylous ascites is the accumulation of a milk-like peritoneal fluid rich in triglycerides, due to the presence of intestinal lymph in the abdominal cavity. The most common causes of chylous acites in adults are abdominal malignancy and cirrhosis. Very few cases of chylous ascites associated to blunt abdominal trauma have been published in the literature. CLINICAL CASE: A 27-year-old, female patient was admitted to the emergency department (ED) with abdominal pain due to a deceleration-type traffic accident. During surveillance the patient presented a progressive decrease in hemoglobin levels and an increase in free intra-abdominal fluid detected on computed tomography scan. The patient underwent an exploratory laparoscopy and a milky-looking peritoneal fluid was identified. The diagnosis of chylous ascites was confirmed by the determination of increased triglyceride levels in the peritoneal fluid. A low-fat diet, with a restriction of long-chain triglycerides, was started in the post-operative period and the patient presented a progressive decrease in abdominal drainage. The patient had a favorable clinical and analytical evolution and was discharged on the fifth post-operative day. DISCUSSION: Chylous ascites is an uncommon finding in trauma. Although surgery may be indicated in selected patients, conservative treatment can be effective in most patients, with or without abdominal drainage. A high-protein and low-fat diet, with medium-chain triglycerides, is the indicated dietary regimen to decrease the amount of lymphatic fluid produced. CONCLUSION: Chylous ascites, although rare in trauma patients must be considered in the diferential diagnosis of free peritoneal fluid. Conservative treatment should be considered in the majority of cases reserving invasive treatments for specific situations.

17.
ERJ Open Res ; 6(4)2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33043043

RESUMO

This article discusses a selection of the scientific presentations in the field of interstitial lung diseases (ILDs) that took place at the 2019 European Respiratory Society International Congress in Madrid, Spain. There were sessions from all four groups within Assembly 12: group 12.01 "Idiopathic interstitial pneumonias", group 12.02 "ILDs/diffuse parenchymal lung diseases (DPLDs) of known origin", group 12.03 "Sarcoidosis and other granulomatous ILDs/DPLDs" and group 12.04 "Rare ILDs/DPLDs". The presented studies brought cutting-edge developments on several aspects of these conditions, including pathogenesis, diagnosis and treatment. As many of the ILDs are individually rare, the sharing of experiences and new data that occur during the Congress are very important for physicians interested in ILDs and ILD patients alike.

18.
Nutr Hosp ; 36(6): 1375-1383, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31718204

RESUMO

INTRODUCTION: To associate food consumption according to the groups that make up the food pyramid with the aerobic and anaerobic performance of Brazilian athletes. A cross-sectional study of 168 athletes with a mean age and BMI of 20.84 ± 7.74 years and 22.88 ± 3.1 kg/m², respectively. Maximum power output was significantly associated with the meat and eggs groups (ß = 0.31; p < 0.05). VO2max exhibited a positive relationship with the fruit group (ß = 0.29; p < 0.05). A significant inverse relation between VO2max and the legumes group was observed (ß = -0.76; p < 0.05). The meat and eggs group and the dairy products group had an inverse and significant association with VO2max (ß = -0.43; p < 0.01). Consumption of meat and eggs showed a positive association with anaerobic performance, whereas the same group and the dairy products group had a negative association with aerobic performance.


INTRODUCCIÓN: Asociar el consumo de alimentos según los grupos que componen la pirámide de alimentos con el rendimiento aeróbico y anaeróbico de deportistas brasileños. Estudio transversal de 168 deportistas con una media de edad e IMC de 20,84 ± 7,74 años y 22,88 ± 3,1 kg/m², respectivamente. La potencia máxima se asoció significativamente con el consumo de los grupos de carne y huevos (ß = 0,31; p < 0,05). El VO2max mostró una relación positiva con el grupo de la fruta (ß = 0,29; p < 0,05). Se observó una relación inversa significativa entre el VO2max y el grupo de las leguminosas (ß = −0,76; p < 0,05). El grupo de carnes y huevos y el grupo de productos lácteos tuvieron una asociación inversa y significativa con el VO2max (ß = −0,43; p < 0,01). El consumo de carne y huevos mostró una asociación positiva con el rendimiento anaeróbico, mientras que el mismo grupo y los productos lácteos se asociaron de forma negativa al rendimiento aeróbico.


Assuntos
Desempenho Atlético/fisiologia , Laticínios , Ingestão de Alimentos , Ovos , Carne , Adolescente , Adulto , Brasil , Estudos Transversais , Teste de Esforço , Feminino , Humanos , Masculino , Consumo de Oxigênio , Adulto Jovem
19.
J Vis Exp ; (146)2019 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-31009008

RESUMO

Cave-dwelling animals have evolved a series of morphological and behavioral traits to adapt to their perpetually dark and food-sparse environments. Among these traits, foraging behavior is one of the useful windows into functional advantages of behavioral trait evolution. Presented herein are updated methods for analyzing vibration attraction behavior (VAB: an adaptive foraging behavior) and imaging of associated mechanosensors of cave-adapted tetra, Astyanax mexicanus. In addition, methods are presented for high-throughput tracking of a series of additional cavefish behaviors including hyperactivity and sleep-loss. Cavefish also show asociality, repetitive behavior and higher anxiety. Therefore, cavefish serve as an animal model for evolved behaviors. These methods use free-software and custom-made scripts that can be applied to other types of behavior. These methods provide practical and cost-effective alternatives to commercially available tracking software.


Assuntos
Comportamento Animal/fisiologia , Cavernas , Characidae/fisiologia , Imageamento Tridimensional , Neurônios/citologia , Animais , Ritmo Circadiano/fisiologia , Mecanorreceptores/metabolismo , Fenótipo , Sono , Vibração
20.
Mundo saúde (Impr.) ; 48: e15822024, 2024.
Artigo em Inglês, Português | LILACS-Express | LILACS | ID: biblio-1555706

RESUMO

A síndrome metabólica é caracterizada pela presença concomitante de alteração na glicemia, dislipidemia, elevação da pressão arterial e adiposidade excessiva, os quais elevam o risco cardiovascular. O objetivo deste trabalho foi analisar os parâmetros da síndrome metabólica e a associação com o consumo de alimentos ultraprocessados e bebidas adoçadas em adolescentes com excesso de peso. Realizou-se um estudo transversal, conduzido com 67 adolescentes com excesso de peso, de um ambulatório pediátrico de um hospital público no município de São Paulo. A avaliação antropométrica consistiu na aferição de peso, estatura e circunferência da cintura. Foram coletados dados de glicose, triglicérides, HDL-c, e pressão arterial, e a síndrome metabólica (SM) analisada de acordo com critérios da Associação Brasileira de Nutrologia. O consumo alimentar foi avaliado pelo questionário de frequência alimentar semiquantitativo. A prevalência de síndrome metabólica foi de 56,7%. Os parâmetros mais prevalentes foram redução de HDL-c (71,6%), elevação da pressão arterial sistólica (70,1%) e da glicemia de jejum (64,2%). Observou-se correlação positiva entre a glicemia de jejum e o consumo de alimentos ultra processados e bebidas adoçadas.


Metabolic syndrome is characterized by the concomitant presence of changes in blood glucose, dyslipidemia, elevated blood pressure and excessive adiposity, which increase cardiovascular risk. The objective of this study was to analyze the parameters of metabolic syndrome and the association with the consumption of ultra-processed foods and sweetened beverages in overweight adolescents. A cross-sectional study was carried out with 67 overweight adolescents from a pediatric outpatient clinic of a public hospital in the city of São Paulo. The anthropometric assessment consisted of measuring weight, height and waist circumference. Data on glucose, triglycerides, HDL-c, and blood pressure were collected, and metabolic syndrome (MS) was analyzed according to criteria from the Brazilian Association of Nutrology. Food consumption was assessed using the semi-quantitative food frequency questionnaire. The prevalence of metabolic syndrome was 56.7%. The most prevalent parameters were a reduction in HDL-c (71.6%), and an increase in systolic blood pressure (70.1%) and fasting blood glucose (64.2%). Blood glucose was positively associated with the sweetened beverage consumption score and BMI. It is concluded that there is a high prevalence of metabolic syndrome in adolescents, with glycemia being associated with the consumption of sweetened beverages.

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