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1.
PLoS Genet ; 14(3): e1007241, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29494583

RESUMEN

Interplay between apicobasal cell polarity modules and the cytoskeleton is critical for differentiation and integrity of epithelia. However, this coordination is poorly understood at the level of gene regulation by transcription factors. Here, we establish the Drosophila activating transcription factor 3 (atf3) as a cell polarity response gene acting downstream of the membrane-associated Scribble polarity complex. Loss of the tumor suppressors Scribble or Dlg1 induces atf3 expression via aPKC but independent of Jun-N-terminal kinase (JNK) signaling. Strikingly, removal of Atf3 from Dlg1 deficient cells restores polarized cytoarchitecture, levels and distribution of endosomal trafficking machinery, and differentiation. Conversely, excess Atf3 alters microtubule network, vesicular trafficking and the partition of polarity proteins along the apicobasal axis. Genomic and genetic approaches implicate Atf3 as a regulator of cytoskeleton organization and function, and identify Lamin C as one of its bona fide target genes. By affecting structural features and cell morphology, Atf3 functions in a manner distinct from other transcription factors operating downstream of disrupted cell polarity.


Asunto(s)
Factor de Transcripción Activador 3/metabolismo , Polaridad Celular/fisiología , Proteínas de Drosophila/metabolismo , Factor de Transcripción Activador 3/genética , Animales , Animales Modificados Genéticamente , Diferenciación Celular , Inmunoprecipitación de Cromatina , Proteínas de Drosophila/genética , Drosophila melanogaster/citología , Drosophila melanogaster/genética , Endosomas/metabolismo , Ojo/crecimiento & desarrollo , Discos Imaginales/citología , Discos Imaginales/fisiología , Lamina Tipo A/genética , Lamina Tipo A/metabolismo , Larva , Sistema de Señalización de MAP Quinasas , Proteínas de la Membrana , Motivos de Nucleótidos/fisiología , Proteína Quinasa C/metabolismo , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo
2.
PLoS Genet ; 13(3): e1006647, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28267791

RESUMEN

In the nervous system, glial cells provide crucial insulation and trophic support to neurons and are important for neuronal survival. In reaction to a wide variety of insults, glial cells respond with changes in cell morphology and metabolism to allow repair. Additionally, these cells can acquire migratory and proliferative potential. In particular, after axonal damage or pruning the clearance of axonal debris by glial cells is key for a healthy nervous system. Thus, bidirectional neuron-glial interactions are crucial in development, but little is known about the cellular sensors and signalling pathways involved. In here, we show that decreased cellular fitness in retinal progenitors caused by reduced Drosophila Myc expression triggers non cell-autonomous activation of retinal glia proliferation and overmigration. Glia migration occurs beyond its normal limit near the boundary between differentiated photoreceptors and precursor cells, extending into the progenitor domain. This overmigration is stimulated by JNK activation (and the function of its target Mmp1), while proliferative responses are mediated by Dpp/TGF-ß signalling activation.


Asunto(s)
Proteínas de Unión al ADN/fisiología , Proteínas de Drosophila/fisiología , Neuroglía/metabolismo , Neuronas/metabolismo , Células Fotorreceptoras de Invertebrados/metabolismo , Células Madre/metabolismo , Factores de Transcripción/fisiología , Animales , Apoptosis , Axones/metabolismo , Diferenciación Celular/fisiología , Movimiento Celular , Proliferación Celular , Proteínas de Unión al ADN/genética , Proteínas de Drosophila/genética , Drosophila melanogaster , Matriz Extracelular/metabolismo , Femenino , MAP Quinasa Quinasa 4/metabolismo , Masculino , Neurogénesis , Retina/citología , Transducción de Señal , Factores de Transcripción/genética , Factor de Crecimiento Transformador beta/metabolismo
3.
J Biol Chem ; 291(29): 15243-55, 2016 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-27226529

RESUMEN

Improving potencies through concomitant blockage of multiple epitopes and avid binding by fusing multiple (different) monovalent Nanobody building blocks via linker sequences into one multivalent polypeptide chain is an elegant alternative to affinity maturation. We explored a large and random formatting library of bivalent (combinations of two identical) and biparatopic (combinations of two different) Nanobodies for functional blockade of Pseudomonas aeruginosa PcrV. PcrV is an essential part of the P. aeruginosa type III secretion system (T3SS), and its oligomeric nature allows for multiple complex binding and blocking options. The library screening yielded a large number of promising biparatopic lead candidates, revealing significant (and non-trivial) preferences in terms of Nanobody building block and epitope bin combinations and orientations. Excellent potencies were confirmed upon further characterization in two different P. aeruginosa T3SS-mediated cytotoxicity assays. Three biparatopic Nanobodies were evaluated in a lethal mouse P. aeruginosa challenge pneumonia model, conferring 100% survival upon prophylactic administration and reducing lung P. aeruginosa burden by up to 2 logs. At very low doses, they protected the mice from P. aeruginosa infection-related changes in lung histology, myeloperoxidase production, and lung weight. Importantly, the most potent Nanobody still conferred protection after therapeutic administration up to 24 h post-infection. The concept of screening such formatting libraries for potency improvement is applicable to other targets and biological therapeutic platforms.


Asunto(s)
Antígenos Bacterianos/inmunología , Toxinas Bacterianas/inmunología , Técnicas Químicas Combinatorias/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Proteínas Citotóxicas Formadoras de Poros/inmunología , Anticuerpos de Dominio Único/inmunología , Potencia de la Vacuna , Animales , Muerte Celular , Modelos Animales de Enfermedad , Mapeo Epitopo , Epítopos/química , Epítopos/inmunología , Femenino , Humanos , Ratones Endogámicos C57BL , Modelos Moleculares , Neumonía/inmunología , Neumonía/microbiología , Neumonía/patología , Infecciones por Pseudomonas/inmunología , Pseudomonas aeruginosa/inmunología
4.
Glia ; 63(7): 1155-65, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25731761

RESUMEN

Cellular migration and differentiation are important developmental processes that require dynamic cellular adhesion. Integrins are heterodimeric transmembrane receptors that play key roles in adhesion plasticity. Here, we explore the developing visual system of Drosophila to study the roles of integrin heterodimers in glia development. Our data show that αPS2 is essential for retinal glia migration from the brain into the eye disc and that glial cells have a role in the maintenance of the fenestrated membrane (Laminin-rich ECM layer) in the disc. Interestingly, the absence of glial cells in the eye disc did not affect the targeting of retinal axons to the optic stalk. In contrast, αPS3 is not required for retinal glia migration, but together with Talin, it functions in glial cells to allow photoreceptor axons to target the optic stalk. Thus, we present evidence that αPS2 and αPS3 integrin have different and specific functions in the development of retinal glia.


Asunto(s)
Comunicación Celular/fisiología , Proteínas de Drosophila/metabolismo , Cadenas alfa de Integrinas/metabolismo , Neuroglía/fisiología , Células Fotorreceptoras de Vertebrados/fisiología , Animales , Animales Modificados Genéticamente , Axones/fisiología , Drosophila , Proteínas de Drosophila/genética , Inmunohistoquímica , Cadenas alfa de Integrinas/genética , Microscopía Electrónica de Transmisión , Interferencia de ARN , Talina/metabolismo
5.
Int J Nurs Sci ; 11(2): 241-257, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38707687

RESUMEN

Objectives: Chronic dyspnea, a distressing symptom in patients with complex chronic conditions, is linked to higher risks of mortality. This study aimed to identify nursing interventions that could improve self-management for complex chronic patients, thereby enhancing control over chronic dyspnea. The findings intend to guide nursing care strategies that promote self-management among this population. Methods: We searched the databases Medline, Scopus, Web of Science, CINAHL, Cochrane Database of Systematic Reviews (CDSR), and Joanna Briggs Institute (JBI) databases were searched in December 2023. We included adult patients with complex chronic conditions with chronic dyspnoea. The team screened articles collaboratively, using Rayyan software. A qualitative appraisal was performed according to JBI Critical Appraisal Checklist tools. The review protocol is registered under the number CRD42023456021. Results: Our review included 18 studies that explored a variety of interventions for chronic dyspnea. We identified pharmacological interventions (such as oxygen therapy and inhalation treatments) and non-pharmacological approaches (including educational programs, breathing exercises, fluid intake management, body awareness techniques, peer support, emotional intelligence training, and the use of web applications). Those interventions empower patients, improve their ability to fulfill life roles, mitigate emotional distress, and improve overall quality of life. Nursing care can be crucial in enabling individuals to achieve independence and autonomy in self-care. Conclusions: Promoting self-management for chronic dyspnea in complex chronic patients requires a holistic approach, encompassing multidisciplinary interventions, individualized self-care education, peer engagement, and technological support. Current research on self-management inadequately addresses interventions targeting patient behaviour change. It highlights the need to delve deeper into the self-management process. Further research is needed to expand the evidence base and refine these interventions.

6.
Rev Port Cardiol ; 29(2): 309-14, 2010 Feb.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-20545255

RESUMEN

Aortic valve stenosis can be complicated by gastrointestinal bleeding from angiodysplasia. A deficiency of high molecular weight multimers of von Willebrand factor (vWF) (type 2A von Willebrand disease) provides the link between this association, which is known as Heyde syndrome. Aortic valve replacement corrects the vWF abnormalities with long-term resolution of gastrointestinal bleeding. The authors present a case report and a review of this association.


Asunto(s)
Angiodisplasia/complicaciones , Estenosis de la Válvula Aórtica/complicaciones , Hemorragia Gastrointestinal/etiología , Anciano , Humanos , Masculino , Síndrome
7.
Rev Assoc Med Bras (1992) ; 66(2): 109-111, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32428142

RESUMEN

Goiter is a localized or generalized thyroid hypertrophy. It can remain within the cervical region or grow down until it invades the mediastinum. The signs and symptoms depend on the size and location of the goiter. Although drugs and radioactive iodine are often used to treat thyroid disease, the presence of symptomatic substernal goiter is a clear indication for surgery. Death or postoperative complications rarely occur. We present a case of a 71-year-old man with recurrent thyroid pathology in the form of substernal goiter and hyperthyroidism even after partial thyroidectomy. The importance of this relates to the clinical evolution, volume, and location of the goiter as well as the surgical and pharmacological approach.


Asunto(s)
Bocio Subesternal/patología , Bocio Subesternal/cirugía , Tiroidectomía/métodos , Anciano , Bocio Subesternal/diagnóstico por imagen , Humanos , Masculino , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento
8.
Rev Assoc Med Bras (1992) ; 66(1): 12-17, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32130375

RESUMEN

Drug-induced liver injury (DILI) to flucloxacillin is rare and is classified as idiosyncratic, as it is dependent on individual susceptibility, unpredictable, and dose-independent. The authors present the case of a 74 - year - old man with a history of monoclonal gammopathy under investigation and alcoholic habits of 24 g/day, with asthenia, anorexia, nausea, abdominal discomfort, and fever with three days of evolution. He was treated with two courses of antibiotic therapy with flucloxacillin to erysipelas previously (3 months and 2 weeks before admission). Lab tests showed serum AST levels of 349 U/L, ALT 646 U/L, alkaline phosphatase 302 U/L, GGT 652 U/L, total bilirubin 3.3 mg/dL and direct bilirubin 2.72 mg/dL. Infectious, autoimmune, and metabolic causes were ruled out. Magnetic resonance cholangiopancreatography showed normal results. Liver biopsy showed mild multifocal (predominantly microvesicular) steatosis; marked changes in the centrilobular areas (sinusoidal dilatation, marked congestion, hemorrhage, and multifocal hepatocyte collapse); expansion of the portal areas with the formation of bridges; proliferated bile ducts and inflammatory infiltrate of variable density, predominantly mononuclear type. The HLA-B*5701 screening test was positive. Hepatic biochemical tests remain abnormal with a significative increase in total bilirubin, which reached levels of 24.1 mg/dL, with the development of jaundice, pruritus, and choluria. DILI was assumed, and the patient was treated with ursodeoxycholic acid. There was favorable evolution, without evidence of blood coagulation dysfunction or encephalopathy. The analytic normalization was, however, slow, with evolution to chronicity. The authors present this case to remind the possibility of moderate/severe drug-induced liver injury to flucloxacillin, an antibiotic commonly used in clinical practice and association with the HLA-B * 5701 allele reported in the literature.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Floxacilina/efectos adversos , Antígenos HLA-B/efectos de los fármacos , Anciano , Enfermedad Hepática Inducida por Sustancias y Drogas/enzimología , Humanos , Inmunoelectroforesis/métodos , Hígado/efectos de los fármacos , Hígado/patología , Masculino , Factores de Riesgo
9.
Eur J Case Rep Intern Med ; 6(7): 001118, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31410350

RESUMEN

A masquerade syndrome is an ophthalmological entity where a neoplasm mimics an inflammatory condition. Ocular melanoma (chiefly uveal) may present with symptoms suggestive of intraocular inflammation such as endogenous endophthalmitis. Ocular melanoma is most commonly found in middle-aged and older caucasian patients. One-third of all uveal melanoma cases present asymptomatically. Early diagnosis facilitates treatment before ocular melanoma reaches metastatic stage IV. Current therapy options for stage IV patients are palliative care and clinical trial participation. LEARNING POINTS: Masquerade syndrome and intraocular haemorrhage can hide a neoplastic aetiology.A biopsy should be carried out for correct diagnosis if intraocular haemorrhage is present and a neoplastic pathology is suspected.A multidisciplinary approach should be adopted to enhance the quality of life of patients with metastatic ocular melanoma.

10.
Open Biol ; 7(1)2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-28123053

RESUMEN

Signalling by TGFß superfamily factors plays an important role in tissue growth and cell proliferation. In Drosophila, the activity of the TGFß/Activin signalling branch has been linked to the regulation of cell growth and proliferation, but the cellular and molecular basis for these functions are not fully understood. In this study, we show that both the RII receptor Punt (Put) and the R-Smad Smad2 are strongly required for cell and tissue growth. Knocking down the expression of Put or Smad2 in salivary glands causes alterations in nucleolar structure and functions. Cells with decreased TGFß/Activin signalling accumulate intermediate pre-rRNA transcripts containing internal transcribed spacer 1 regions accompanied by the nucleolar retention of ribosomal proteins. Thus, our results show that TGFß/Activin signalling is required for ribosomal biogenesis, a key aspect of cellular growth control. Importantly, overexpression of Put enhanced cell growth induced by Drosophila Myc, a well-characterized inducer of nucleolar hypertrophy and ribosome biogenesis.


Asunto(s)
Receptores de Activinas Tipo II/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crecimiento & desarrollo , Ribosomas/metabolismo , Glándulas Salivales/embriología , Proteína Smad2/metabolismo , Receptores de Activinas Tipo II/genética , Activinas/metabolismo , Animales , Ciclo Celular , Nucléolo Celular/metabolismo , Proliferación Celular , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Regulación del Desarrollo de la Expresión Génica , Técnicas de Silenciamiento del Gen , Glándulas Salivales/metabolismo , Transducción de Señal , Proteínas Smad Reguladas por Receptores , Proteína Smad2/genética , Factor de Crecimiento Transformador beta/metabolismo
11.
Rev. Assoc. Med. Bras. (1992, Impr.) ; Rev. Assoc. Med. Bras. (1992, Impr.);66(2): 109-111, Feb. 2020. graf
Artículo en Inglés | SES-SP, LILACS | ID: biblio-1136168

RESUMEN

SUMMARY Goiter is a localized or generalized thyroid hypertrophy. It can remain within the cervical region or grow down until it invades the mediastinum. The signs and symptoms depend on the size and location of the goiter. Although drugs and radioactive iodine are often used to treat thyroid disease, the presence of symptomatic substernal goiter is a clear indication for surgery. Death or postoperative complications rarely occur. We present a case of a 71-year-old man with recurrent thyroid pathology in the form of substernal goiter and hyperthyroidism even after partial thyroidectomy. The importance of this relates to the clinical evolution, volume, and location of the goiter as well as the surgical and pharmacological approach.


RESUMO O bócio é a hipertrofia da glândula tiroide localizada ou generalizada. Esta pode localizar-se na região cervical ou crescer através do mediastino. Os sinais e sintomas dependem do tamanho e da localização do bócio. Embora os fármacos e o iodo radioativo sejam frequentemente usados para tratar doenças tireoidianas, a presença do bócio subesternal sintomático é uma clara indicação para a cirurgia. A morte ou complicações pós-operatórias são raras. Apresentamos o caso de um homem de 71 anos com recorrência de patologia tireoidiana sob a forma de bócio subesternal e hipertireoidismo após tireoidectomia parcial. A importância desse caso relaciona-se com a evolução clínica, o volume e a localização do bócio e a abordagem cirúrgica e farmacológica desse tipo de patologia.


Asunto(s)
Humanos , Masculino , Anciano , Tiroidectomía/métodos , Bocio Subesternal/cirugía , Bocio Subesternal/patología , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento , Bocio Subesternal/diagnóstico por imagen
12.
Rev. Assoc. Med. Bras. (1992, Impr.) ; Rev. Assoc. Med. Bras. (1992, Impr.);66(1): 12-17, Jan. 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1091907

RESUMEN

SUMMARY Drug-induced liver injury (DILI) to flucloxacillin is rare and is classified as idiosyncratic, as it is dependent on individual susceptibility, unpredictable, and dose-independent. The authors present the case of a 74 - year - old man with a history of monoclonal gammopathy under investigation and alcoholic habits of 24 g/day, with asthenia, anorexia, nausea, abdominal discomfort, and fever with three days of evolution. He was treated with two courses of antibiotic therapy with flucloxacillin to erysipelas previously (3 months and 2 weeks before admission). Lab tests showed serum AST levels of 349 U/L, ALT 646 U/L, alkaline phosphatase 302 U/L, GGT 652 U/L, total bilirubin 3.3 mg/dL and direct bilirubin 2.72 mg/dL. Infectious, autoimmune, and metabolic causes were ruled out. Magnetic resonance cholangiopancreatography showed normal results. Liver biopsy showed mild multifocal (predominantly microvesicular) steatosis; marked changes in the centrilobular areas (sinusoidal dilatation, marked congestion, hemorrhage, and multifocal hepatocyte collapse); expansion of the portal areas with the formation of bridges; proliferated bile ducts and inflammatory infiltrate of variable density, predominantly mononuclear type. The HLA-B*5701 screening test was positive. Hepatic biochemical tests remain abnormal with a significative increase in total bilirubin, which reached levels of 24.1 mg/dL, with the development of jaundice, pruritus, and choluria. DILI was assumed, and the patient was treated with ursodeoxycholic acid. There was favorable evolution, without evidence of blood coagulation dysfunction or encephalopathy. The analytic normalization was, however, slow, with evolution to chronicity. The authors present this case to remind the possibility of moderate/severe drug-induced liver injury to flucloxacillin, an antibiotic commonly used in clinical practice and association with the HLA-B * 5701 allele reported in the literature.


RESUMO A hepatotoxicidade à flucloxacilina é rara e classifica-se como idiossincrática, uma vez que é dependente da suscetibilidade individual, não expectável e independente da dose. Apresentamos o caso de um homem, 74 anos, antecedentes de gamapatia monoclonal e hábitos alcoólicos de 24 g/dia, com quadro de astenia, anorexia, náuseas, desconforto abdominal e febrícula com três dias de evolução. Referência a dois ciclos de antibioterapia com flucloxacilina por erisipela (três meses e duas semanas antes da admissão). Analiticamente com AST 349 U/L, ALT 646 U/L, FA 302 U/L, GGT 652 U/L, bilirrubina total 3,3 mg/dL, bilirrubina direta 2,72 mg/dL. Excluídas etiologias infecciosa, autoimune, metabólica, bem como patologia das vias biliares por colangio-RM. Biópsia hepática mostrou esteatose multifocal ligeira (predominantemente microvesicular); alterações acentuadas nas áreas centrolobulares (dilatação sinusoidal, congestão acentuada, hemorragia e colapso multifocal de hepatócitos); expansão das áreas portais com constituição de pontes; ductos biliares proliferados e infiltrado inflamatório de densidade variável, predominantemente de tipo mononucleado. Tipagem de HLA-B*5701 positiva. Agravamento analítico atingindo bilirrubina total 24,1 mg/dL, com desenvolvimento de icterícia, prurido e colúria. Admitida a hepatotoxicidade, iniciou terapêutica com ácido ursodesoxicólico. Verificou-se evolução favorável, sem evidência de coagulopatia ou encefalopatia. A normalização analítica foi, no entanto, lenta, com evolução para cronicidade. Os autores apresentam este caso para alertar para a possibilidade de hepatotoxicidade moderada a grave à flucloxacilina, antibiótico de uso comum na prática clínica e associação com o alelo HLA-B*5701 relatada na literatura.


Asunto(s)
Humanos , Anciano , Antígenos HLA-B/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Floxacilina/efectos adversos , Inmunoelectroforesis/métodos , Factores de Riesgo , Enfermedad Hepática Inducida por Sustancias y Drogas/enzimología , Hígado/efectos de los fármacos , Hígado/patología
13.
Anal Chem ; 80(5): 1482-92, 2008 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-18247519

RESUMEN

Seventeen samples from paintings by the distinguished 19th century Portuguese painter, Henrique Pousão, were characterized by micro-X-ray diffractometry and infrared and Raman microspectroscopy. The main advantages and limitations of each technique for pigment identification are outlined, revealing the need for the use of complementary techniques. Pousão's palette is discussed.

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