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1.
Nucleic Acids Res ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953170

RESUMO

BRCA2 is an essential tumor suppressor protein involved in promoting faithful repair of DNA lesions. The activity of BRCA2 needs to be tuned precisely to be active when and where it is needed. Here, we quantified the spatio-temporal dynamics of BRCA2 in living cells using aberration-corrected multifocal microscopy (acMFM). Using multicolor imaging to identify DNA damage sites, we were able to quantify its dynamic motion patterns in the nucleus and at DNA damage sites. While a large fraction of BRCA2 molecules localized near DNA damage sites appear immobile, an additional fraction of molecules exhibits subdiffusive motion, providing a potential mechanism to retain an increased number of molecules at DNA lesions. Super-resolution microscopy revealed inhomogeneous localization of BRCA2 relative to other DNA repair factors at sites of DNA damage. This suggests the presence of multiple nanoscale compartments in the chromatin surrounding the DNA lesion, which could play an important role in the contribution of BRCA2 to the regulation of the repair process.

2.
Gen Comp Endocrinol ; 330: 114150, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36349607

RESUMO

Among all the regulatory homeostatic networks in vertebrates, the activation of the hypothalamic-pituitaryadrenal axis during the stress response, has gained considerable attention, and the measurement of fecal glucocorticoids (FGC) has become an invaluable tool to assess adrenocortical activity related to stressful events in wild and captive animals. However, the use of FGC requires the validation of measurement techniques and the proper selection of the specific hormone according to the study species. The main objective of this study was to identify the dominant glucocorticoid (GC) hormone in the stress response of black-tailed prairie dogs (Cynomys ludovicianus) in an arid grassland of Chihuahua, Mexico. A capture stress challenge in the field was developed to determine if the levels of glucocorticoids (cortisol and corticosterone) both in serum and fecal samples could be attributed to stress in Cynomys ludovicianus. The samples were analysed with the technique of liquid phase radioimmunoassay , and this study showed that both cortisol and corticosterone are present at measurable levels in serum and fecal samples of black-tailed prairie dogs. We found that both GCs were present in similar concentrations in serum, however, corticosterone concentration in fecal samples was higher than cortisol. Likewise, biochemical validations performed in this study to test the assay reached acceptable levels of reliability. Therefore, we confirm that fecal analysis can be implemented as a method to measure stress responses in wild prairie dogs.


Assuntos
Corticosterona , Glucocorticoides , Animais , Hidrocortisona , México , Reprodutibilidade dos Testes , Sciuridae
3.
Nucleic Acids Res ; 48(6): 3071-3088, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-32016368

RESUMO

During protein synthesis, charged tRNAs deliver amino acids to translating ribosomes, and are then re-charged by tRNA synthetases (aaRS). In humans, mutant aaRS cause a diversity of neurological disorders, but their molecular aetiologies are incompletely characterised. To understand system responses to aaRS depletion, the yeast glutamine aaRS gene (GLN4) was transcriptionally regulated using doxycycline by tet-off control. Depletion of Gln4p inhibited growth, and induced a GCN4 amino acid starvation response, indicative of uncharged tRNA accumulation and Gcn2 kinase activation. Using a global model of translation that included aaRS recharging, Gln4p depletion was simulated, confirming slowed translation. Modelling also revealed that Gln4p depletion causes negative feedback that matches translational demand for Gln-tRNAGln to aaRS recharging capacity. This maintains normal charged tRNAGln levels despite Gln4p depletion, confirmed experimentally using tRNA Northern blotting. Model analysis resolves the paradox that Gln4p depletion triggers a GCN4 response, despite maintenance of tRNAGln charging levels, revealing that normally, the aaRS population can sequester free, uncharged tRNAs during aminoacylation. Gln4p depletion reduces this sequestration capacity, allowing uncharged tRNAGln to interact with Gcn2 kinase. The study sheds new light on mutant aaRS disease aetiologies, and explains how aaRS sequestration of uncharged tRNAs can prevent GCN4 activation under non-starvation conditions.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/genética , Proteínas Serina-Treonina Quinases/genética , RNA de Transferência de Glutamina/genética , RNA de Transferência/genética , Proteínas de Saccharomyces cerevisiae/genética , Aminoácidos/genética , Aminoácidos/metabolismo , Aminoacil-tRNA Sintetases/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Homeostase , Fosforilação , RNA de Transferência de Glutamina/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Inanição/genética , Inanição/metabolismo
4.
BMC Gastroenterol ; 21(1): 31, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33478385

RESUMO

BACKGROUND: Percutaneous Endoscopic Gastrostomy (PEG) can involve some complications, despite the good safety of its track record. The Buried Bumper Syndrome (BBS) is a rare, late and dangerous complication that consists in the erosion of the internal bumper through the gastric wall. Case presentation We report the development of BBS in a man with chronic obstructive pulmonary disease (COPD) who had a persistent chronic cough which was prevalently but not solely in the morning and required placement of a PEG tube for continuous infusion of Levodopa/carbidopa intestinal gel for advanced Parkinson's disease. CONCLUSION: We believe that COPD with chronic cough while not representing an absolute contraindication to PEG placement, may potentially cause BBS and therefore an appropriate regimen of tube care by expert personnel is mandatory in this setting.


Assuntos
Gastrostomia , Doença Pulmonar Obstrutiva Crônica , Contraindicações , Tosse/etiologia , Nutrição Enteral , Humanos , Masculino , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/terapia
5.
J Physiol ; 597(9): 2483-2514, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30908629

RESUMO

KEY POINTS: Purkinje cells in the cerebellum integrate input from sensory organs with that from premotor centres. Purkinje cells use a variety of sensory inputs relaying information from the environment to modify motor control. Here we investigated to what extent the climbing fibre inputs to Purkinje cells signal mono- or multi-sensory information, and to what extent this signalling is subject to recent history of activity. We show that individual climbing fibres convey multiple types of sensory information, together providing a rich mosaic projection pattern of sensory signals across the cerebellar cortex. Moreover, firing probability of climbing fibres following sensory stimulation depends strongly on the recent history of activity, showing a tendency to homeostatic dampening. ABSTRACT: Cerebellar Purkinje cells integrate sensory information with motor efference copies to adapt movements to behavioural and environmental requirements. They produce complex spikes that are triggered by the activity of climbing fibres originating in neurons of the inferior olive. These complex spikes can shape the onset, amplitude and direction of movements and the adaptation of such movements to sensory feedback. Clusters of nearby inferior olive neurons project to parasagittally aligned stripes of Purkinje cells, referred to as 'microzones'. It is currently unclear to what extent individual Purkinje cells within a single microzone integrate climbing fibre inputs from multiple sources of different sensory origins, and to what extent sensory-evoked climbing fibre responses depend on the strength and recent history of activation. Here we imaged complex spike responses in cerebellar lobule crus 1 to various types of sensory stimulation in awake mice. We find that different sensory modalities and receptive fields have a mild, but consistent, tendency to converge on individual Purkinje cells, with climbing fibres showing some degree of input-specificity. Purkinje cells encoding the same stimulus show increased events with coherent complex spike firing and tend to lie close together. Moreover, whereas complex spike firing is only mildly affected by variations in stimulus strength, it depends strongly on the recent history of climbing fibre activity. Our data point towards a mechanism in the olivo-cerebellar system that regulates complex spike firing during mono- or multi-sensory stimulation around a relatively low set-point, highlighting an integrative coding scheme of complex spike firing under homeostatic control.


Assuntos
Potenciais de Ação , Retroalimentação Sensorial , Núcleo Olivar/fisiologia , Vibrissas/fisiologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Núcleo Olivar/citologia , Células de Purkinje/fisiologia , Percepção do Tato , Vibrissas/inervação
6.
J Virol ; 92(22)2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30158289

RESUMO

Rabies virus is a neurovirulent RNA virus, which causes about 59,000 human deaths each year. Treatment for rabies does not exist due to incomplete understanding of the pathogenesis. MALT1 mediates activation of several immune cell types and is involved in the proliferation and survival of cancer cells. MALT1 acts as a scaffold protein for NF-κB signaling and a cysteine protease that cleaves substrates, leading to the expression of immunoregulatory genes. Here, we examined the impact of genetic or pharmacological MALT1 inhibition in mice on disease development after infection with the virulent rabies virus strain CVS-11. Morbidity and mortality were significantly delayed in Malt1-/- compared to Malt1+/+ mice, and this effect was associated with lower viral load, proinflammatory gene expression, and infiltration and activation of immune cells in the brain. Specific deletion of Malt1 in T cells also delayed disease development, while deletion in myeloid cells, neuronal cells, or NK cells had no effect. Disease development was also delayed in mice treated with the MALT1 protease inhibitor mepazine and in knock-in mice expressing a catalytically inactive MALT1 mutant protein, showing an important role of MALT1 proteolytic activity. The described protective effect of MALT1 inhibition against infection with a virulent rabies virus is the precise opposite of the sensitizing effect of MALT1 inhibition that we previously observed in the case of infection with an attenuated rabies virus strain. Together, these data demonstrate that the role of immunoregulatory responses in rabies pathogenicity is dependent on virus virulence and reveal the potential of MALT1 inhibition for therapeutic intervention.IMPORTANCE Rabies virus is a neurotropic RNA virus that causes encephalitis and still poses an enormous challenge to animal and public health. Efforts to establish reliable therapeutic strategies have been unsuccessful and are hampered by gaps in the understanding of virus pathogenicity. MALT1 is an intracellular protease that mediates the activation of several innate and adaptive immune cells in response to multiple receptors, and therapeutic MALT1 targeting is believed to be a valid approach for autoimmunity and MALT1-addicted cancers. Here, we study the impact of MALT1 deficiency on brain inflammation and disease development in response to infection of mice with the highly virulent CVS-11 rabies virus. We demonstrate that pharmacological or genetic MALT1 inhibition decreases neuroinflammation and extends the survival of CVS-11-infected mice, providing new insights in the biology of MALT1 and rabies virus infection.


Assuntos
Encéfalo/imunologia , Inflamação/prevenção & controle , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/fisiologia , Vírus da Raiva/imunologia , Raiva/prevenção & controle , Linfócitos T/imunologia , Animais , Encéfalo/metabolismo , Encéfalo/virologia , Células Cultivadas , Inflamação/imunologia , Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/antagonistas & inibidores , Raiva/imunologia , Raiva/metabolismo , Linfócitos T/patologia , Linfócitos T/virologia
7.
J Virol ; 92(8)2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29367251

RESUMO

MALT1 is involved in the activation of immune responses, as well as in the proliferation and survival of certain cancer cells. MALT1 acts as a scaffold protein for NF-κB signaling and a cysteine protease that cleaves substrates, further promoting the expression of immunoregulatory genes. Deregulated MALT1 activity has been associated with autoimmunity and cancer, implicating MALT1 as a new therapeutic target. Although MALT1 deficiency has been shown to protect against experimental autoimmune encephalomyelitis, nothing is known about the impact of MALT1 on virus infection in the central nervous system. Here, we studied infection with an attenuated rabies virus, Evelyn-Rotnycki-Abelseth (ERA) virus, and observed increased susceptibility with ERA virus in MALT1-/- mice. Indeed, after intranasal infection with ERA virus, wild-type mice developed mild transient clinical signs with recovery at 35 days postinoculation (dpi). Interestingly, MALT1-/- mice developed severe disease requiring euthanasia at around 17 dpi. A decreased induction of inflammatory gene expression and cell infiltration and activation was observed in MALT1-/- mice at 10 dpi compared to MALT1+/+ infected mice. At 17 dpi, however, the level of inflammatory cell activation was comparable to that observed in MALT1+/+ mice. Moreover, MALT1-/- mice failed to produce virus-neutralizing antibodies. Similar results were obtained with specific inactivation of MALT1 in T cells. Finally, treatment of wild-type mice with mepazine, a MALT1 protease inhibitor, also led to mortality upon ERA virus infection. These data emphasize the importance of early inflammation and activation of T cells through MALT1 for controlling the virulence of an attenuated rabies virus in the brain.IMPORTANCE Rabies virus is a neurotropic virus which can infect any mammal. Annually, 59,000 people die from rabies. Effective therapy is lacking and hampered by gaps in the understanding of virus pathogenicity. MALT1 is an intracellular protein involved in innate and adaptive immunity and is an interesting therapeutic target because MALT1-deregulated activity has been associated with autoimmunity and cancers. The role of MALT1 in viral infection is, however, largely unknown. Here, we study the impact of MALT1 on virus infection in the brain, using the attenuated ERA rabies virus in different models of MALT1-deficient mice. We reveal the importance of MALT1-mediated inflammation and T cell activation to control ERA virus, providing new insights in the biology of MALT1 and rabies virus infection.


Assuntos
Encéfalo/imunologia , Ativação Linfocitária , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/imunologia , Vírus da Raiva/imunologia , Raiva/imunologia , Linfócitos T/imunologia , Animais , Encéfalo/patologia , Encéfalo/virologia , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Inflamação/virologia , Camundongos , Camundongos Knockout , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/genética , Raiva/genética , Raiva/patologia , Vírus da Raiva/genética , Linfócitos T/patologia
8.
J Biol Regul Homeost Agents ; 33(3 Suppl. 1): 145-151. DENTAL SUPPLEMENT, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31538461

RESUMO

Nonsyndromic cleft lip with or without cleft palate is the most common craniofacial anomaly affecting around 1 in 700 live births worldwide. Clefts of the human face can be classified anatomically as cleft palate only (CPO), cleft lip only (CLO), cleft lip and palate (CLP) or a combined group of cleft lip with or without cleft palate (CL/P), based on different in embryologic development. These malformations have some genetic origin, in fact several association studies have been performed to obtain important information about the candidate genes; but more important are gene-environment interactions that play an increasing role in its etiology. Epidemiological studies have shown how environmental factors (alcohol, smoking, drugs), as well as possible gene-environment interactions, play an important role in the onset of the malformation. On the contrary, folic acid intake seems to have a protective effect. In this review, we analyze the role of environmental factors related to onset of cleft.


Assuntos
Fenda Labial/etiologia , Fissura Palatina/etiologia , Consumo de Bebidas Alcoólicas/efeitos adversos , Fenda Labial/genética , Fissura Palatina/genética , Ácido Fólico/administração & dosagem , Interação Gene-Ambiente , Humanos , Fumar/efeitos adversos , Transtornos Relacionados ao Uso de Substâncias/complicações
9.
J Biol Regul Homeost Agents ; 33(3 Suppl. 1): 169-172. DENTAL SUPPLEMENT, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31538464

RESUMO

Mandibular third molars (MM3s) are responsible for pericoronitis, primary and/or secondary crowding of the dentition, odontogenic tumors and cysts, periodontal defects associated with the posterior part of mandibular second molars. Tooth extraction is indicated for prophylactic and therapeutic purpose in patients with problems caused by impacted teeth. Common postoperative complications associated with third molar extraction are alveolitis (0.5e32.5%), infection (0.9e4.2%), postoperative bleeding (0.2e1.5%), transient dysfunction of the inferior alveolar nerve (0.6e5.5%), and permanent dysfunction of the inferior alveolar nerve (0.1e0.9%). A literature review reveals number of individual case reports of accidental displacement to various anatomical locations, namely, the infratemporal fossa, pterygomandibular space, lateral pharyngeal space, submandibular space, and sublingual space.


Assuntos
Dente Serotino/cirurgia , Extração Dentária/efeitos adversos , Dente Impactado/cirurgia , Humanos , Mandíbula
10.
Nutr Metab Cardiovasc Dis ; 29(6): 598-603, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30954416

RESUMO

BACKGROUND AND AIMS: Screening for Gestational Diabetes (GDM) is usually recommended between 24 and 28 weeks of pregnancy; however available evidence suggests that GDM may be already present before recommended time for screening, in particular among high-risk women as those with prior GDM or obesity. The purpose of this retrospective study was to evaluate whether early screening (16-18 weeks) and treatment of GDM may improve maternal and fetal outcomes. METHODS AND RESULTS: In 290 women at high-risk for GDM, we analyzed maternal and fetal outcomes, according to early or standard screening and GDM diagnosis time. Early screening was performed by 50% of high-risk women. The prevalence of GDM was 62%. Among those who underwent early screened, GDM was diagnosed at the first evaluation in 42.7%. Women with early diagnosis were more frequently treated with insulin and had a slightly lower HbA1c than women with who were diagnosed late. No differences were observed in the prevalence of Cesarean section, operative delivery, gestational age at the delivery, macrosomia, neonatal weight, Ponderal Index and Large-for-Gestational-Age among women with early or late GDM diagnosis or NGT. However, compared to NGT women, GDM women, irrespective of the time of diagnosis, had a lower gestational weight gain, lower prevalence of macrosomia (3.9% vs. 11.4%), small (1.7% vs. 8.3%) as well as large for gestational age (3.3% vs. 16.7%), but higher prevalence of pre-term delivery (8.9% vs. 2.7%). CONCLUSION: Early vs. standard screening and treatment of GDM in high-risk women is associated with similar short-term maternal-fetal outcomes, although women with an early diagnosis were treated to a greater extent with insulin therapy.


Assuntos
Diabetes Gestacional/diagnóstico , Diabetes Gestacional/tratamento farmacológico , Intervenção Médica Precoce , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Programas de Rastreamento , Cuidado Pré-Natal/métodos , Adulto , Diabetes Gestacional/sangue , Diabetes Gestacional/epidemiologia , Diagnóstico Precoce , Feminino , Humanos , Itália/epidemiologia , Valor Preditivo dos Testes , Gravidez , Resultado da Gravidez , Prevalência , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
11.
Neurol Sci ; 40(7): 1425-1431, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30941628

RESUMO

To improve patient care and help clinical research, the Neuropathic Pain Special Interest Group of the Italian Neurological Society appointed a task force to elaborate a consensus statement on pharmacoresistant neuropathic pain. The task force included 19 experts in neuropathic pain. These experts participated in a Delphi survey consisting of three consecutive rounds of questions and a face-to-face meeting, designed to achieve a consensus definition of pharmacoresistant neuropathic pain. In the three rounds of questions, the participants identified and described the main distinguishing features of pharmacoresistance. In the face-to-face meeting the participants discussed the clinical features determining pharmacoresistance. They finally agreed that neuropathic pain is pharmacoresistant when "the patient does not reach the 50% reduction of pain or an improvement of at least 2 points in the Patient Global Impression of Change, having used all drug classes indicated as first, second, or third line in the most recent and widely agreed international guidelines, for at least 1 month after titration to the highest tolerable dose." Our consensus statement might be useful for identifying eligible patients for invasive treatments, and selecting patients in pharmacological trials, thus improving patient care and helping clinical research.


Assuntos
Neuralgia/classificação , Dor Intratável/classificação , Técnica Delphi , Resistência a Medicamentos , Humanos , Neuralgia/diagnóstico , Neuralgia/terapia , Dor Intratável/diagnóstico , Dor Intratável/terapia
13.
Exp Parasitol ; 207: 107778, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31629698

RESUMO

The murine infection with Taenia crassiceps WFU (T. crassiceps WFU) cysticerci has been widely used as an experimental model to better understand human cysticercosis. Several reports have established that the host hormonal environment determines the susceptibility and severity of many parasite infections. Female mice are more susceptible to infection with T. crassiceps cysticerci suggesting that a rich estrogen environment facilitates their reproduction. Ovarian androgens and estrogens are synthesized by key enzymes as P450-aromatase and 17α-hydroxilase/17, 20 lyase (P450C17). The aim of this study was to determine the effect of chronic intraperitoneal infection of T. crassiceps WFU cysticerci on mice ovarian follicular development, ovulation, the expression of ovarian P450-aromatase and P450C17, and serum 17ß-estradiol, key enzymes of the ovarian steroidogenic pathway. To perform this study ovaries and serum were obtained at two, four and six months from T. crassiceps WFU cysticerci infected mice, and compared to those of healthy animals. The ovaries were fixed and processed for histology or lysed in RIPA buffer for Western blot using specific antibodies for P450C17 and P450-aromatase. 17ß-estradiol serum concentration was measured by ELISA. The results showed that the infection with T. crassiceps WFU cysticerci significantly reduced the number of primordial and primary follicles after two months of infection. Through the course of the study, the corpus luteum number began to decrease, whereas atretic follicles increased. The expression of ovarian P450C17 and P450-aromatase as well as serum E2 concentration were significantly increased in the infected group compared to control. These findings show that chronic infection with Taenia crassiceps WFU may alter the reproductive functions of the female mice host.


Assuntos
Estradiol/sangue , Folículo Ovariano/fisiologia , Ovário/enzimologia , Teníase/fisiopatologia , Análise de Variância , Animais , Western Blotting , Peso Corporal , Corpo Lúteo/patologia , Densitometria , Ensaio de Imunoadsorção Enzimática , Tubas Uterinas/patologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Ovário/anatomia & histologia , Distribuição Aleatória , Esteroide 17-alfa-Hidroxilase/metabolismo , Teníase/sangue , Teníase/enzimologia , Útero/anatomia & histologia
14.
Pharmacogenomics J ; 18(1): 56-63, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-27958379

RESUMO

This study was designed to investigate the mode of action of trabectedin in myelomonocytic leukemia cells by applying systems biology approaches to mine gene expression profiling data and pharmacological assessment of the cellular effects. Significant enrichment was found in regulons of target genes inferred for specific transcription factors, among which MAFB was the most upregulated after treatment and was central in the transcriptional network likely to be relevant for the specific therapeutic effects of trabectedin against myelomonocytic cells. Using the Connectivity Map, similarity among transcriptional signatures elicited by treatment with different compounds was investigated, showing a high degree of similarity between transcriptional signatures of trabectedin and those of the topoisomerase I inhibitor, irinotecan, and an anti-dopaminergic antagonist, thioridazine. The study highlights the potential importance of systems biology approaches to generate new hypotheses that are experimentally testable to define the specificity of the mechanism of action of drugs.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Leucemia Mieloide/tratamento farmacológico , Trabectedina/farmacologia , Linhagem Celular Tumoral , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes/efeitos dos fármacos , Humanos , Biologia de Sistemas/métodos , Transcrição Gênica/efeitos dos fármacos
15.
Phys Rev Lett ; 120(12): 128101, 2018 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-29694095

RESUMO

One of the greatest challenges in biophysical models of translation is to identify coding sequence features that affect the rate of translation and therefore the overall protein production in the cell. We propose an analytic method to solve a translation model based on the inhomogeneous totally asymmetric simple exclusion process, which allows us to unveil simple design principles of nucleotide sequences determining protein production rates. Our solution shows an excellent agreement when compared to numerical genome-wide simulations of S. cerevisiae transcript sequences and predicts that the first 10 codons, which is the ribosome footprint length on the mRNA, together with the value of the initiation rate, are the main determinants of protein production rate under physiological conditions. Finally, we interpret the obtained analytic results based on the evolutionary role of the codons' choice for regulating translation rates and ribosome densities.


Assuntos
Modelos Genéticos , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sequência de Bases , Saccharomyces cerevisiae/genética , Relação Estrutura-Atividade
16.
PLoS Comput Biol ; 13(5): e1005555, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28558053

RESUMO

The well established phenomenon of ribosome drop-off plays crucial roles in translational accuracy and nutrient starvation responses during protein translation. When cells are under stress conditions, such as amino acid starvation or aminoacyl-tRNA depletion due to a high level of recombinant protein expression, ribosome drop-off can substantially affect the efficiency of protein expression. Here we introduce a mathematical model that describes the effects of ribosome drop-off on the ribosome density along the mRNA and on the concomitant protein synthesis rate. Our results show that ribosome premature termination may lead to non-intuitive ribosome density profiles, such as a ribosome density which increases from the 5' to the 3' end. Importantly, the model predicts that the effects of ribosome drop-off on the translation rate are mRNA-specific, and we quantify their resilience to drop-off, showing that the mRNAs which present ribosome queues are much less affected by ribosome drop-off than those which do not. Moreover, among those mRNAs that do not present ribosome queues, resilience to drop-off correlates positively with the elongation rate, so that sequences using fast codons are expected to be less affected by ribosome drop-off. This result is consistent with a genome-wide analysis of S. cerevisiae, which reveals that under favourable growth conditions mRNAs coding for proteins involved in the translation machinery, known to be highly codon biased and using preferentially fast codons, are highly resilient to ribosome drop-off. Moreover, in physiological conditions, the translation rate of mRNAs coding for regulatory, stress-related proteins, is less resilient to ribosome drop-off. This model therefore allows analysis of variations in the translational efficiency of individual mRNAs by accounting for the full range of known ribosome behaviours, as well as explaining mRNA-specific variations in ribosome density emerging from ribosome profiling studies.


Assuntos
Polirribossomos/genética , Biossíntese de Proteínas/fisiologia , RNA Mensageiro/genética , Ribossomos/genética , Biologia Computacional , Polirribossomos/metabolismo , RNA Fúngico/genética , RNA Fúngico/metabolismo , RNA Mensageiro/metabolismo , Ribossomos/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
17.
Eur J Neurol ; 25(11): 1341-1344, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29935029

RESUMO

BACKGROUND AND PURPOSE: Adult-onset laryngeal dystonia (LD) can be isolated or can be associated with dystonia in other body parts. Combined forms can be segmental at the onset or can result from dystonia spread to or from the larynx. The aim of this study was to identify the main clinical and demographic features of adult-onset idiopathic LD in an Italian population with special focus on dystonia spread. METHODS: Data were obtained from the Italian Dystonia Registry (IDR) produced by 37 Italian institutions. Clinical and demographic data of 71 patients with idiopathic adult-onset LD were extracted from a pool of 1131 subjects included in the IDR. RESULTS: Fifty of 71 patients presented a laryngeal focal onset; the remaining subjects had onset in other body regions and later laryngeal spread. The two groups did not show significant differences of demographic features. 32% of patients with laryngeal onset reported spread to contiguous body regions afterwards and in most cases (12 of 16 subjects) dystonia started to spread within 1 year from the onset. LD patients who remained focal and those who had dystonia spread did not show other differences. CONCLUSIONS: Data from IDR show that dystonic patients with focal laryngeal onset will present spread in almost one-third of cases. Spread from the larynx occurs early and is directed to contiguous body regions showing similarities with clinical progression of blepharospasm. This study gives a new accurate description of LD phenomenology that may contribute to improving the comprehension of dystonia pathophysiology.


Assuntos
Distonia/diagnóstico , Distúrbios Distônicos/diagnóstico , Doenças da Laringe/diagnóstico , Fatores Etários , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Fatores Sexuais
18.
J Biol Regul Homeost Agents ; 32(2 Suppl. 1): 149-158, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29460535

RESUMO

Plastic surgery is gaining more and more popularity, while stigma and popular myths about it are gradually decreasing. Analyze My Face conjunctly deals with the two main problems of facial plastic surgery: the excessive rate of dissatisfaction, which results in high revision requests and negative psychological side-effects and the “diagnosis by procedure” approach, which leads to erroneous measurements. This new and innovative method of Digital Facial Analysis is a direct non-expensive online service that provides professional and documented in-depth consultation to patients before they decide to undergo any type of facial intervention. The paper thoroughly explains the scientific method with which professionals provide customers with a facial assessment based on specific parameters which will be discussed (height, width, proportions, direction of facial growth, the way they assess each facial area in detail (eyes, mouth, cartilage), and the motivations for which they suggest to correct eventual defects through precise measurements, indicators and suggested interventions. Long-term evaluation of stability of surgical results and patient satisfaction achieved with digital facial analysis has not yet been established and needs further research. However, it is important to underline that the AMF approach tends to consider exclusively possible and feasible procedures that do not compromise functionality and that do not put patients in danger of serious damage. Problems or deformities that cannot be treated are always indicated. AMF aims to maximize professionality by giving practitioners an additional tool to aid their work, give unbiased opinions and look at the overall picture. It also aims to help patients by soothing their way into the complicated world of aesthetic surgery.


Assuntos
Face , Cirurgia Plástica , Humanos , Satisfação do Paciente , Procedimentos de Cirurgia Plástica
19.
Gen Comp Endocrinol ; 259: 154-160, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29174867

RESUMO

Taeniids tapeworms are hermaphroditic helminths that gradually develop testis and ovaries in their reproductive units. The larval stage of the tapeworms named cysticercus is a vesicle that contains the scolex and proliferates asexually in the abdominal cavity of mice. Once in the host, they evaginate, attach to the gut and develop into an adult organism, the tapeworm. We have previously reported reported that T. crassiceps ORF and solium cysticerci transform steroid precursors to androgens and estrogens. Taenia crassiceps WFU cysticerci can also synthesize corticosteroids. The aim of the present work is to investigate the relationship between steroid synthesis ability and the developmental stage of the parasite T. crassiceps WFU. To this purpose, cysticerci were obtained from the abdominal cavity of female mice, manually separated in invaginated (IC) and evaginated parasites (EC) and preincubated for 24 h in DMEM plus antibiotics/antimycotics. Next step consisted in incubation for different periods in the fresh media added with tritiated androstenedione (3H-A4) or progesterone (3H-P4) and incubated for different periods. Taenia crassiceps WFU tapeworms were recovered from the intestine of golden hamsters that had been orally infected with cysticerci. The worms were pre-cultured in DMEM plus FBS and antibiotics, and then incubated without FBS for different time periods, in the presence of 3H-A4 or 3H-P4. At the end of the experiments the media from cysticerci and tapeworms were analyzed by thin layer chromatography. Results showed that testosterone synthesis was significantly higher in the evaginated cysticerci and increased with time in culture. The invaginated and evaginated cysticerci also synthesized small quantities of 17ß-estradiol (E2) and estrone. The evaginated cysticerci synthesized twice more 3H-deoxycorticosterone (3H-DOC) than the invaginated parasites, the production increased significantly with time in culture. Taenia crassiceps WFU tapeworms synthesized significant quantities of 3H-testosterone and small amounts of estrone after only 3 h of culture in the presence of 3H-A4. The tapeworms also transformed 3H-P4 to 3H-DOC and increased its synthesis after 24 h in culture. In summary, our data show the pathways that T. crassiceps WFU cysticerci use to synthesize sexual steroids in both larval developmental stages and reveals the steroidogenic capacity of the tapeworms.


Assuntos
Parasitos/crescimento & desenvolvimento , Esteroides/metabolismo , Androstenodiona/metabolismo , Animais , Cysticercus , Feminino , Camundongos , Taenia
20.
Neurol Sci ; 39(5): 975, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29687311

RESUMO

In the original article, Gina Ferrazzano was affiliated to Department of Neurology and Psychiatry, Neuromed Institute IRCCS, Sapienza University of Rome, Pozzilli, Italy.The corrected affiliation should be: Neuromed Institute IRCCS, Pozzilli, IS, Italy.

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