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1.
Medicina (Kaunas) ; 60(1)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38256428

RESUMO

Breast cancer is a prevalent malignancy in the present day, particularly affecting women as one of the most common forms of cancer. A significant portion of patients initially present with localized disease, for which curative treatments are pursued. Conversely, another substantial segment is diagnosed with metastatic disease, which has a worse prognosis. Recent years have witnessed a profound transformation in the prognosis for this latter group, primarily due to the discovery of various biomarkers and the emergence of targeted therapies. These biomarkers, encompassing serological, histological, and genetic indicators, have demonstrated their value across multiple aspects of breast cancer management. They play crucial roles in initial diagnosis, aiding in the detection of relapses during follow-up, guiding the application of targeted treatments, and offering valuable insights for prognostic stratification, especially for highly aggressive tumor types. Molecular markers have now become the keystone of metastatic breast cancer diagnosis, given the diverse array of chemotherapy options and treatment modalities available. These markers signify a transformative shift in the arsenal of therapeutic options against breast cancer. Their diagnostic precision enables the categorization of tumors with elevated risks of recurrence, increased aggressiveness, and heightened mortality. Furthermore, the existence of therapies tailored to target specific molecular anomalies triggers a cascade of changes in tumor behavior. Therefore, the primary objective of this article is to offer a comprehensive review of the clinical, diagnostic, prognostic, and therapeutic utility of the principal biomarkers currently in use, as well as of their clinical impact on metastatic breast cancer. In doing so, our goal is to contribute to a more profound comprehension of this complex disease and, ultimately, to enhance patient outcomes through more precise and effective treatment strategies.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/terapia , Seguimentos , Recidiva Local de Neoplasia/diagnóstico , Biomarcadores , Agressão
2.
Curr Probl Cardiol ; 49(2): 102193, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37952788

RESUMO

INTRODUCTION: The evidence supporting pharmacological heart failure treatment relies on randomized clinical trials with stringent inclusion and exclusion criteria. OBJECTIVES: Assess the eligibility of outpatients with chronic heart failure for the trials DAPA-HF, EMPEROR-reduced, and PARADIGM-HF, while exploring potential differences among study populations. METHODS: By reviewing medical records, we determined the eligibility rate for each study and evaluated the incidence of heart failure hospitalizations and all-cause mortality during this period. RESULTS: A total of 446 patients were included in the cohort. Approximately 75% would be ineligible for the trials, mainly because of their comorbidities. Ineligible patients had a higher all-cause mortality, but a similar incidence of hospitalization. CONCLUSION: Approximately 1 in 4 patients from a heart failure clinic in Medellin, Colombia would meet the eligibility criteria for the DAPA-HF, EMPEROR-reduced, and PARADIGM-HF trials. These findings highlight the need to complement randomized clinical trials with real-world data.


Assuntos
Cardiologia , Insuficiência Cardíaca , Humanos , Valsartana/uso terapêutico , Volume Sistólico , Tetrazóis/efeitos adversos , Estudos Retrospectivos , Colômbia/epidemiologia , Antagonistas de Receptores de Angiotensina/uso terapêutico , Combinação de Medicamentos , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia
3.
Int J Mol Sci ; 24(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38069190

RESUMO

Epilepsy is a neurological disorder characterized by abnormal neuronal excitability, with glutamate playing a key role as the predominant excitatory neurotransmitter involved in seizures. Animal models of epilepsy are crucial in advancing epilepsy research by faithfully replicating the diverse symptoms of this disorder. In particular, the GASH/Sal (genetically audiogenic seizure-prone hamster from Salamanca) model exhibits seizures resembling human generalized tonic-clonic convulsions. A single nucleotide polymorphism (SNP; C9586732T, p.His289Tyr) in the Grik1 gene (which encodes the kainate receptor GluK1) has been previously identified in this strain. The H289Y mutation affects the amino-terminal domain of GluK1, which is related to the subunit assembly and trafficking. We used confocal microscopy in Xenopus oocytes to investigate how the H289Y mutation, compared to the wild type (WT), affects the expression and cell-surface trafficking of GluK1 receptors. Additionally, we employed the two-electrode voltage-clamp technique to examine the functional effects of the H289Y mutation. Our results indicate that this mutation increases the expression and incorporation of GluK1 receptors into an oocyte's membrane, enhancing kainate-evoked currents, without affecting their functional properties. Although further research is needed to fully understand the molecular mechanisms responsible for this epilepsy, the H289Y mutation in GluK1 may be part of the molecular basis underlying the seizure-prone circuitry in the GASH/Sal model.


Assuntos
Epilepsia Reflexa , Cricetinae , Animais , Humanos , Xenopus laevis/metabolismo , Epilepsia Reflexa/genética , Convulsões/metabolismo , Receptores de Ácido Caínico/metabolismo , Oócitos/metabolismo
4.
Rev. colomb. gastroenterol ; 38(3)sept. 2023.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1535933

RESUMO

We present the case of a 17-year-old patient with no known comorbidity or history who was admitted due to dysphagia. Endoscopy revealed ulcerated lesions in the distal esophagus that were positive for herpes simplex virus type 1 (HSV-1) on immunohistochemistry. An examination of HSV-1 esophagitis in the immunocompetent patient is made.


Se presenta el caso de un paciente de 17 años sin ninguna comorbilidad ni antecedente conocido que ingresó por disfagia. La endoscopia reveló lesiones ulceradas en el esófago distal que resultaron positivas para virus del herpes simple tipo 1 (VHS-1) en la inmunohistoquímica. Se hace una revisión de la esofagitis por VHS-1 en el paciente inmunocompetente.

5.
Int J Mol Sci ; 24(9)2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37175931

RESUMO

The aim of this study is to evaluate molecules involved in oxidative stress (OS), inflammation, angiogenesis, and apoptosis, and discern which of these are more likely to be implicated in proliferative diabetic retinopathy (PDR) and diabetic macular edema (DME) by investigating the correlation between them in the plasma (PLS) and vitreous body (VIT), as well as examining data obtained from ophthalmological examinations. Type 2 diabetic (T2DM) patients with PDR/DME (PDRG/DMEG; n = 112) and non-DM subjects as the surrogate controls (SCG n = 48) were selected according to the inclusion/exclusion criteria and programming for vitrectomy, either due to having PDR/DME or macular hole (MH)/epiretinal membrane (ERM)/rhegmatogenous retinal detachment. Blood samples were collected and processed to determine the glycemic profile, total cholesterol, and C reactive protein, as well as the malondialdehyde (MDA), 4-hydroxynonenal (4HNE), superoxide dismutase (SOD), and catalase (CAT) levels and total antioxidant capacity (TAC). In addition, interleukin 6 (IL6), vascular endothelial growth factor (VEGF), and caspase 3 (CAS3) were assayed. The VITs were collected and processed to measure the expression levels of all the abovementioned molecules. Statistical analyses were conducted using the R Core Team (2022) program, including group comparisons and correlation analyses. Compared with the SCG, our findings support the presence of molecules involved in OS, inflammation, angiogenesis, and apoptosis in the PLS and VIT samples from T2DM. In PLS from PDRG, there was a decrease in the antioxidant load (p < 0.001) and an increase in pro-angiogenic molecules (p < 0.001), but an increase in pro-oxidants (p < 0.001) and a decline in antioxidants (p < 0.001) intravitreally. In PLS from DMEG, pro-oxidants and pro-inflammatory molecules were augmented (p < 0.001) and the antioxidant capacity diminished (p < 0.001), but the pro-oxidants increased (p < 0.001) and antioxidants decreased (p < 0.001) intravitreally. Furthermore, we found a positive correlation between the PLS-CAT and the VIT-SOD levels (rho = 0.5; p < 0.01) in PDRG, and a negative correlation between the PSD-4HNE and the VIT-TAC levels (rho = 0.5; p < 0.01) in DMEG. Integrative data of retinal imaging variables showed a positive correlation between the central subfield foveal thickness (CSFT) and the VIT-SOD levels (rho = 0.5; p < 0.01), and a negative correlation between the CSFT and the VIT-4HNE levels (rho = 0.4; p < 0.01) in PDRG. In DMEG, the CSFT displayed a negative correlation with the VIT-CAT (rho = 0.5; p < 0.01). Exploring the relationship of the abovementioned potential biomarkers between PLS and VIT may help detecting early molecular changes in PDR/DME, which can be used to identify patients at high risk of progression, as well as to monitor therapeutic outcomes in the diabetic retina.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Edema Macular , Humanos , Retinopatia Diabética/metabolismo , Antioxidantes/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Espécies Reativas de Oxigênio , Estresse Oxidativo , Inflamação , Diabetes Mellitus Tipo 2/complicações , Superóxido Dismutase/metabolismo
6.
Vet Sci ; 10(2)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36851474

RESUMO

A nine year old cross-breed dog was presented with a two week history of ambulatory tetraparesis and proprioceptive ataxia affecting all four limbs. Meningomyelitis of Unknown Origin (MUO) was presumptively diagnosed based on the magnetic resonance imaging (MRI) findings and cerebrospinal fluid (CSF) analysis. The dog received a tapering dose of glucocorticoids and cyclosporine, showing significant improvement and the stabilization of the clinical signs for seven months. After this period, the dog showed an acute clinical deterioration and a follow-up MRI revealed new multiple lesions affecting different spinal nerve roots along the cervicothoracic spinal cord. Following euthanasia, a final diagnose of multiple malignant peripheral nerve sheath tumors (MPNSTs) was made based on the histopathological examination. MPNSTs can affect the cranial nerves, spinal nerves or the associated nerve roots at any location and can lead to secondary spinal cord compression. The aim of the present case report is to describe the clinical presentation and atypical MRI findings of a dog with histologically confirmed multiple MPNSTs. According to the reviewed literature, this is the first reported case of simultaneous MPNSTs in the cervicothoracic spinal cord of a dog.

7.
Sci Rep ; 13(1): 1831, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36726019

RESUMO

We analyze the effect of obesity on the incidence of hypertension, hyperlipidemia and diabetes in USA using a health production theoretical framework along with a bivariate flexible semi-parametric recursive copula model that account for endogeneity. In this approach, the effects of control variables are flexibly determined using additive predictors that allow for a variety of effects. Our findings suggest that there exist a positive and significant effect of obesity on the prevalence of all chronic diseases examined. In particular, after endogeneity is accounted for, the probability of having hypertension, hyperlipidemia and diabetes for obese individuals are, respectively, 35%, 28% and 11% higher than those under the obesity threshold. These findings suggest that lowering obesity rates could lead to significant reductions in the morbidity and mortality associated with these diseases.


Assuntos
Diabetes Mellitus , Hiperlipidemias , Hipertensão , Doenças Metabólicas , Humanos , Obesidade/complicações , Obesidade/epidemiologia , Diabetes Mellitus/epidemiologia , Hiperlipidemias/epidemiologia , Hipertensão/epidemiologia , Prevalência , Doença Crônica
8.
J Clin Med ; 11(19)2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-36233515

RESUMO

Open-angle glaucoma (OAG), the most prevalent clinical type of glaucoma, is still the main cause of irreversible blindness worldwide. OAG is a neurodegenerative illness for which the most important risk factor is elevated intraocular pressure (IOP). Many questions remain unanswered about OAG, such as whether nutritional or toxic habits, other personal characteristics, and/or systemic diseases influence the course of glaucoma. As such, in this study, we performed a multicenter analytical, observational, case-control study of 412 participants of both sexes, aged 40-80 years, that were classified as having ocular hypertension (OHT) or OAG. Our primary endpoint was to investigate the relationship between specific lifestyle habits; anthropometric and endocrine-metabolic, cardiovascular, and respiratory events; and commonly used psychochemicals, with the presence of OHT or OAG in an ophthalmologic population from Spain and Portugal. Demographic, epidemiological, and ocular/systemic clinical data were recorded from all participants. Data were analyzed using the R Statistics v4.1.2 and RStudio v2021.09.1 programs. The mean age was 62 ± 15 years, with 67-80 years old comprising the largest subgroup sample of participants in both study groups. The central corneal thickness (ultrasound pachymetry)-adjusted IOP (Goldman tonometry) in each eye was 20.46 ± 2.35 and 20.1 ± 2.73 mmHg for the OHT individuals, and 15.8 ± 3.83 and 16.94 ± 3.86 mmHg for the OAG patients, with significant differences between groups (both p = 0.001). The highest prevalence of the surveyed characteristics in both groups was for overweight/obesity and daily coffee consumption, followed by psychochemical drug intake, migraine, and peripheral vasospasm. Our data show that overweight/obesity, migraine, asthma, and smoking are major risk factors for conversion from OHT to OAG in this Spanish and Portuguese population.

9.
Vet Sci ; 9(10)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36288127

RESUMO

Gangliogliomas are extremely rare tumors of the nervous system composed of neoplastic glial and neuronal cells. The aim of the present paper is to describe the clinical presentation, magnetic resonance imaging (MRI) findings and histopathological and immunophenotypical characteristics of a cerebral cortex ganglioglioma in a 7-year-old Border Collie. The dog presented an acute onset of tonic-clonic epileptic seizures. MRI revealed a well-defined large intra-axial mass located on the left forebrain, mainly affecting the frontal cortex. Following humane euthanasia, the histopathological examination of the mass revealed a diffuse proliferation of neoplastic glial cells mixed with anomalous neuronal bodies. Immunohistochemical analyses confirmed the presence of two different populations of neoplastic cells. Most neoplastic glial cells were immunoreactive to glial fibrillary acidic protein (GFAP) and the other subset of neoplastic cells were positive to neuronal markers such as PGP 9.5, synaptophysin (SYN) and neuron-specific enolase (NSE), suggestive of neuronal cells. These findings confirmed the diagnosis of a cerebrocortical ganglioglioma. To the authors knowledge, this is the first description of a ganglioglioma of the cerebral cortex in a dog.

10.
Eur J Cancer ; 175: 110-119, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36099670

RESUMO

BACKGROUND: We aimed to compare the efficacy and safety of maintaining or withdrawing abiraterone acetate plus prednisone (AAP) in patients with metastatic castration-resistant prostate cancer who had experienced cancer progression to this treatment and were beginning a docetaxel-based therapy. PATIENTS AND METHODS: Phase II, randomised, open-label study conducted in patients with metastatic castration-resistant prostate cancer who were asymptomatic or mildly symptomatic. After open-label treatment with AAP, patients who had experienced cancer progression to AAP were randomised to 75 mg/m2 of docetaxel plus AAP or to receive 75 mg/m2 of docetaxel plus 10 mg of prednisone orally daily. The primary outcome was the radiographic progression-free survival rate at 12 months as evaluated by the investigators in all randomised patients. RESULTS: A total of 148 patients were included in open-label treatment with AAP, and of them, 94 patients were randomised to receive either docetaxel plus AAP (intervention group; n = 47) or docetaxel plus prednisone (control group; n = 47). The 12-month radiographic progression-free survival rates did not differ between the intervention group (34.9%; 95% CI 20.7-49.2) and the control group (33.9%; 95% CI 19.5-48.3). There were no significant differences in the time to radiographic progression and the overall survival between the intervention and control groups. Grade 3-5 neutropenia with the combination of docetaxel plus prednisone and AA was more frequent than with docetaxel plus prednisone (59.6% versus 27.7%). CONCLUSION: Our results indicate that the therapeutic strategy of maintaining AAP added to docetaxel in chemotherapy-naïve patients who have experienced cancer progression to AAP treatment should not be further evaluated and should be avoided in clinical practice. CLINICAL TRIALS: NCT02036060 https://clinicaltrials.gov/ct2/show/NCT02036060.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de Próstata Resistentes à Castração , Acetato de Abiraterona/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Progressão da Doença , Docetaxel/uso terapêutico , Humanos , Masculino , Prednisona , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/patologia , Resultado do Tratamento
11.
Rev. crim ; 64(1): [83-94], 2022.
Artigo em Espanhol | LILACS | ID: biblio-1369481

RESUMO

La delincuencia es un fenómeno complejo que permea y afecta profundamente nuestra sociedad. A pesar de que existen innumerables estudios sobre la conducta delictiva, las investigaciones han dejado a un lado la variable de género, la cual marca una diferencia importante en la explicación de las conductas humanas. Esto genera no solo vacíos teóricos, sino también dificultades en la comprensión, explicación y posible solución de este fenómeno. Por ello se realizó una revisión bibliográfica entorno a las diferencias de género en la conducta delictiva, contexto penitenciario y tratamiento para la reinserción social, donde se logró identificar 59 artículos seleccionados de las principales bases de datos científicas, durante el periodo 2000-2020. Se encontró que las mujeres que cometen actos delictivos deben ser sujetas a un tratamiento particular, diseñado en función de las características particulares de su perfil criminal y de las necesidades especiales que su propio género exige. Lo anterior implica un abordaje multicausal y multidisciplinar que dirija el desarrollo de programas que logren atender a esta población de una manera pertinente y eficaz.


Assuntos
Mulheres , Estabelecimentos Correcionais
12.
Front Microbiol ; 12: 781760, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956147

RESUMO

Cyanobacteria, phototrophic organisms performing oxygenic photosynthesis, must adapt their metabolic processes to important environmental challenges, like those imposed by the succession of days and nights. Not surprisingly, certain regulatory proteins are found exclusively in this phylum. One of these unique proteins, PipX, provides a mechanistic link between signals of carbon/nitrogen and of energy, transduced by the signaling protein PII, and the control of gene expression by the global nitrogen regulator NtcA. PII, required for cell survival unless PipX is inactivated or downregulated, functions by protein-protein interactions with transcriptional regulators, transporters, and enzymes. PipX also functions by protein-protein interactions, and previous studies suggested the existence of additional interacting partners or included it into a relatively robust six-node synteny network with proteins apparently unrelated to the nitrogen regulation system. To investigate additional functions of PipX while providing a proof of concept for the recently developed cyanobacterial linkage network, here we analyzed the physical and regulatory interactions between PipX and an intriguing component of the PipX synteny network, the essential ribosome assembly GTPase EngA. The results provide additional insights into the functions of cyanobacterial EngA and of PipX, showing that PipX interacts with the GD1 domain of EngA in a guanosine diphosphate-dependent manner and interferes with EngA functions in Synechococcus elongatus at a low temperature, an environmentally relevant context. Therefore, this work expands the PipX interaction network and establishes a possible connection between nitrogen regulation and the translation machinery. We discuss a regulatory model integrating previous information on PII-PipX with the results presented in this work.

13.
Sci Rep ; 11(1): 7389, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795764

RESUMO

To assess the predictive and prognostic aim of interim and end-treatment 18F-fluorocholine PET/CT (FCH-PET/CT) and 99mTc-methilen diphosphonate bone scintigraphy (BS) in patients with castration-resistant prostate cancer and bone metastases (CRPC-BM) treated with Radium 223 dichloride (223Ra). Prospective and multicentre ChoPET-Rad study including 82 patients with CRPC-BM. Baseline, after 3 (interim) and 6 doses (end-treatment) BS and FCH PET/CT were performed in patients who meet the study criteria. Clinical variables, imaging and clinical progression were obtained and their association with progression free survival (PFS), and overall survival (OS) was studied. Agreement between BS and FCH PET/CT response was assessed using Kappa (K) analysis. Median of PFS and OS was 3 and 16 months, respectively. Agreement between interim BS and FCH PET/CT was weak (K: 0.28; p = 0.004). No agreement was observed between end-treatment diagnostic studies. Interim and end-treatment FCH PET/CT were related to PFS (p = 0.011 and p < 0.001, respectively). Therapeutic failure and interim BS and FCH PET/CT showed association with OS (p < 0.001, p = 0.037 and p = 0.008, respectively). Interim and end-treatment FCH PET/CT were good predictors of biochemical progression in patients treated with 223Ra. Therapeutic failure and progression in interim BS or FCH PET/CT were adverse factors for OS.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Osso e Ossos/diagnóstico por imagem , Colina/análogos & derivados , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias da Próstata/diagnóstico por imagem , Rádio (Elemento)/química , Idoso , Neoplasias Ósseas/secundário , Colina/química , Progressão da Doença , Intervalo Livre de Doença , Humanos , Masculino , Pessoa de Meia-Idade , Medicina Molecular , Análise Multivariada , Modelos de Riscos Proporcionais , Estudos Prospectivos , Radioisótopos/química , Reprodutibilidade dos Testes , Resultado do Tratamento
14.
FEBS J ; 288(4): 1142-1162, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32599651

RESUMO

The PII-like protein CutA is annotated as being involved in Cu2+ tolerance, based on analysis of Escherichia coli mutants. However, the precise cellular function of CutA remains unclear. Our bioinformatic analysis reveals that CutA proteins are universally distributed across all domains of life. Based on sequence-based clustering, we chose representative cyanobacterial CutA proteins for physiological, biochemical, and structural characterization and examined their involvement in heavy metal tolerance, by generating CutA mutants in filamentous Nostoc sp. and in unicellular Synechococcus elongatus. However, we were unable to find any involvement of cyanobacterial CutA in metal tolerance under various conditions. This prompted us to re-examine experimentally the role of CutA in protecting E. coli from Cu2+ . Since we found no effect on copper tolerance, we conclude that CutA plays a different role that is not involved in metal protection. We resolved high-resolution CutA structures from Nostoc and S. elongatus. Similarly to their counterpart from E. coli and to canonical PII proteins, cyanobacterial CutA proteins are trimeric in solution and in crystal structure; however, no binding affinity for small signaling molecules or for Cu2+ could be detected. The clefts between the CutA subunits, corresponding to the binding pockets of PII proteins, are formed by conserved aromatic and charged residues, suggesting a conserved binding/signaling function for CutA. In fact, we find binding of organic Bis-Tris/MES molecules in CutA crystal structures, revealing a strong tendency of these pockets to accommodate cargo. This highlights the need to search for the potential physiological ligands and for their signaling functions upon binding to CutA. DATABASES: Structural data are available in Protein Data Bank (PDB) under the accession numbers 6GDU, 6GDV, 6GDW, 6GDX, 6T76, and 6T7E.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Proteínas de Bactérias/química , Metais Pesados/farmacologia , Nostoc/química , Synechococcus/química , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Calorimetria/métodos , Cobre/farmacologia , Cristalografia por Raios X , Modelos Moleculares , Mutação , Nostoc/genética , Nostoc/metabolismo , Conformação Proteica , Multimerização Proteica , Homologia de Sequência de Aminoácidos , Transdução de Sinais/efeitos dos fármacos , Synechococcus/genética , Synechococcus/metabolismo
15.
Life (Basel) ; 10(6)2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32481703

RESUMO

PipX is a unique cyanobacterial protein identified by its ability to bind to PII and NtcA, two key regulators involved in the integration of signals of the nitrogen/carbon and energy status, with a tremendous impact on nitrogen assimilation and gene expression in cyanobacteria. PipX provides a mechanistic link between PII, the most widely distributed signaling protein, and NtcA, a global transcriptional regulator of cyanobacteria. PII, required for cell survival unless PipX is inactivated or down-regulated, functions by protein-protein interactions with transcriptional regulators, transporters, and enzymes. In addition, PipX appears to be involved in a wider signaling network, supported by the following observations: (i) PII-PipX complexes interact with PlmA, an as yet poorly characterized transcriptional regulator also restricted to cyanobacteria; (ii) the pipX gene is functionally connected with pipY, a gene encoding a universally conserved pyridoxal phosphate binding protein (PLPBP) involved in vitamin B6 and amino acid homeostasis, whose loss-of-function mutations cause B6-dependent epilepsy in humans, and (iii) pipX is part of a relatively robust, six-node synteny network that includes pipY and four additional genes that might also be functionally connected with pipX. In this overview, we propose that the study of the protein-protein interaction and synteny networks involving PipX would contribute to understanding the peculiarities and idiosyncrasy of signaling pathways that are conserved in cyanobacteria.

16.
Environ Microbiol Rep ; 11(4): 495-507, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30126050

RESUMO

Cyanobacteria, phototrophic organisms performing oxygenic photosynthesis, must adapt their metabolic processes to important environmental challenges, like those imposed by the succession of days and nights. Not surprisingly, certain regulatory proteins are found exclusively in this phylum. One of these unique factors, PipX, provides a mechanistic link between signals of carbon/nitrogen and of energy, transduced by the signalling protein PII, and the control of gene expression by the global nitrogen regulator NtcA. Here we report a new regulatory function of PipX: enhancement in cis of pipY expression, a gene encoding a universally conserved protein involved in amino/keto acid and Pyridoxal phosphate homeostasis. In Synechococcus elongatus and many other cyanobacteria these genes are expressed as a bicistronic pipXY operon. Despite being cis-acting, polarity suppression by PipX is nevertheless reminiscent of the function of NusG paralogues typified by RfaH, which are non-essential operon-specific bacterial factors acting in trans to upregulate horizontally-acquired genes. Furthermore, PipX and members of the NusG superfamily share a TLD/KOW structural domain, suggesting regulatory interactions of PipX with the translation machinery. Our results also suggest that the cis-acting function of PipX is a sophisticated regulatory strategy for maintaining appropriate PipX-PipY stoichiometry.


Assuntos
Regulação Bacteriana da Expressão Gênica , Óperon/genética , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , DNA Intergênico , Nitrogênio/metabolismo , Domínios Proteicos , Relação Estrutura-Atividade , Synechococcus/genética , Synechococcus/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/genética
17.
Sci Total Environ ; 650(Pt 2): 3134-3144, 2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30373090

RESUMO

A field experiment was conducted during 15 months to study the effects of four arbuscular mycorrhizal fungi (AMF) on the growth of Ricinus communis accession SF7. Plants were established on amended soil (vermicompost:sawdust:soil 1:1:1) severely polluted by lead-acid batteries (LAB) located at Mexico State, Mexico. Plants inoculated with Acaulospora sp., Funneliformis mosseae and Gigaspora gigantea had 100% survival in comparison to non-inoculated plants (57%). These same AMF enhanced palmitic and linoleic acids content in seeds of R. communis. Acaulospora sp. modified rhizosphere soil pH and decreased 3.5 folds Pb foliar concentrations while F. mosseae BEG25 decreased three times Pb soil availability in comparison to non-inoculated plants. Spatial changes in Pb soil availability were observed at the end of this research. No fungal effect on P, Ca, Cu foliar concentrations, soluble sugars, proline, chlorophyll or on the activity of two oxidative stress enzymes was observed. Mycorrhizal colonization from the inoculated fungi was between 40% and 60%, while colonization by native fungi was between 16% and 22%. A similar percentage of foliar total phenolic compounds was observed in non-mycorrhizal plants and those inoculated with G. gigantea and Acaulospora sp. This is the first research reporting effects of AMF on R. communis (castor bean) shrubs when grown on a LAB recycling site suggesting the use of Acaulospora sp. and F. mosseae BEG25 in phytostabilization to ameliorate Pb pollution and decreasing its ecological risk.


Assuntos
Recuperação e Remediação Ambiental , Chumbo/metabolismo , Micorrizas/metabolismo , Ricinus/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Biocombustíveis , Fontes de Energia Elétrica , Poluição Ambiental/análise , México , Reciclagem
18.
Cir. Esp. (Ed. impr.) ; 96(5): 283-291, mayo 2018. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-176337

RESUMO

INTRODUCCIÓN: El objetivo del estudio es analizar la tasa de reconstrucción del estoma tras cirugía por diverticulitis aguda complicada (DAC), su demora, factibilidad, complicaciones y factores de riesgo de mantenerlo. MÉTODOS: Estudio retrospectivo multicéntrico de pacientes intervenidos mediante cirugía urgente por DAC con realización de un estoma en 10 hospitales durante 6 años. Se analiza la frecuencia de reconstrucción del estoma, fundamentalmente de los terminales, y el tiempo en que se produce, así como los factores relacionados con ella. RESULTADOS: De 385 pacientes intervenidos por DAC, a 312 (81%) se les realizó un estoma: 292 fueron colostomías terminales y 20 estomas derivativos. Durante el seguimiento, en 161 (51,6%), se intentó el cierre a una mediana de 9 meses. Las causas más frecuentes de no efectuarlo fueron la comorbilidad y el fallecimiento del paciente. La edad más avanzada se mostró factor adverso en el análisis multivariante y la tasa actuarial de reconstrucción fue mayor en hombres y en quienes no se realizó un Hartmann. La cirugía pudo completarse en todos menos en un paciente y en 4 se asoció un estoma derivativo. La morbimortalidad fue del 35,7 y 1,9%, respectivamente. Hubo un 8,4% de reintervenciones y un 6% de fallos de sutura, quedando 12 pacientes (7,9%) con un estoma tras el intento de reconstrucción. CONCLUSIONES: La cirugía de la DAC se asocia muy frecuentemente a la construcción de un estoma terminal, que en casi un 50% no se reconstruirá. Además, la intervención de reconstrucción tiene una demora notable y está asociada a una morbimortalidad nada despreciable


INTRODUCTION: The aim was to analyse the stoma reversal rate after surgery for complicated acute diverticulitis (CAD), and more specifically the end-stoma-reversal, as well as the delay, feasibility, complications and risk factors for stoma maintenance. METHODS: A multicentre retrospective study of patients who had undergone urgent surgery for CAD with stoma formation in ten hospitals during a period of 6 years. The frequency of reversal over time and the factors affecting the decision for reversal were analysed. RESULTS: Out of 385 patients operated for CAD, 312 underwent stoma creation: 292 end colostomies and 20 diverting stomas. During follow-up, stoma reversal surgery was performed in 161 patients (51.6%) after a median of 9 months. The main causes for not performing stoma reversal were comorbidities and the death of the patient. Advanced age was an adverse factor in the multivariate analysis, and the actuarial rate of reversal was higher in men and in patients with no previous Hartmann's operation. Stoma reversal surgery was completed in all but one patient, and a loop ileostomy was associated in four. Morbidity and mortality rates were 35.7% and 1.9%, respectively. A total of 8.4% of patients underwent re-operation, and 6% experienced an anastomotic leak. Twelve patients remained with a stoma after the attempted reconstruction surgery. CONCLUSIONS: Surgery for CAD is frequently associated with an end stoma, which will ultimately not be reversed in almost 50% of patients. Moreover, reversal surgery is frequently delayed and is associated with significant morbidity and mortality


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Doenças do Colo/cirurgia , Colostomia , Diverticulite/cirurgia , Doenças do Íleo/cirurgia , Ileostomia , Doenças do Colo/complicações , Diverticulite/complicações , Doenças do Íleo/complicações , Estudos Retrospectivos
19.
Cir Esp (Engl Ed) ; 96(5): 283-291, 2018 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29530275

RESUMO

INTRODUCTION THE AIM: was to analyse the stoma reversal rate after surgery for complicated acute diverticulitis (CAD), and more specifically the end-stoma-reversal, as well as the delay, feasibility, complications and risk factors for stoma maintenance. METHODS: A multicentre retrospective study of patients who had undergone urgent surgery for CAD with stoma formation in ten hospitals during a period of 6 years. The frequency of reversal over time and the factors affecting the decision for reversal were analysed. RESULTS: Out of 385 patients operated for CAD, 312 underwent stoma creation: 292 end colostomies and 20 diverting stomas. During follow-up, stoma reversal surgery was performed in 161 patients (51.6%) after a median of 9 months. The main causes for not performing stoma reversal were comorbidities and the death of the patient. Advanced age was an adverse factor in the multivariate analysis, and the actuarial rate of reversal was higher in men and in patients with no previous Hartmann's operation. Stoma reversal surgery was completed in all but one patient, and a loop ileostomy was associated in four. Morbidity and mortality rates were 35.7% and 1.9%, respectively. A total of 8.4% of patients underwent re-operation, and 6% experienced an anastomotic leak. Twelve patients remained with a stoma after the attempted reconstruction surgery. CONCLUSIONS: Surgery for CAD is frequently associated with an end stoma, which will ultimately not be reversed in almost 50% of patients. Moreover, reversal surgery is frequently delayed and is associated with significant morbidity and mortality.


Assuntos
Doenças do Colo/cirurgia , Colostomia , Diverticulite/cirurgia , Doenças do Íleo/cirurgia , Ileostomia , Doenças do Colo/complicações , Diverticulite/complicações , Feminino , Humanos , Doenças do Íleo/complicações , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
20.
G3 (Bethesda) ; 8(5): 1771-1785, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29588381

RESUMO

Genomic selection (GS) has become a tool for selecting candidates in plant and animal breeding programs. In the case of quantitative traits, it is common to assume that the distribution of the response variable can be approximated by a normal distribution. However, it is known that the selection process leads to skewed distributions. There is vast statistical literature on skewed distributions, but the skew normal distribution is of particular interest in this research. This distribution includes a third parameter that drives the skewness, so that it generalizes the normal distribution. We propose an extension of the Bayesian whole-genome regression to skew normal distribution data in the context of GS applications, where usually the number of predictors vastly exceeds the sample size. However, it can also be applied when the number of predictors is smaller than the sample size. We used a stochastic representation of a skew normal random variable, which allows the implementation of standard Markov Chain Monte Carlo (MCMC) techniques to efficiently fit the proposed model. The predictive ability and goodness of fit of the proposed model were evaluated using simulated and real data, and the results were compared to those obtained by the Bayesian Ridge Regression model. Results indicate that the proposed model has a better fit and is as good as the conventional Bayesian Ridge Regression model for prediction, based on the DIC criterion and cross-validation, respectively. A computing program coded in the R statistical package and C programming language to fit the proposed model is available as supplementary material.


Assuntos
Genômica , Modelos Genéticos , Teorema de Bayes , Simulação por Computador , Resistência à Doença/genética , Método de Monte Carlo , Doenças das Plantas/genética , Análise de Regressão , Zea mays/genética
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