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1.
Plant Cell Environ ; 39(6): 1366-80, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26670204

RESUMO

Sucrose accumulation in leaves in response to various abiotic stresses suggests a specific role of this disaccharide for stress tolerance and adaptation. The high-affinity transporter StSUT1 undergoes substrate-induced endocytosis presenting the question as to whether altered sucrose accumulation in leaves in response to stresses is also related to enhanced endocytosis or altered activity of the sucrose transporter. StSUT1 is known to interact with several stress-inducible proteins; here we investigated whether one of the interacting candidates, StPDI1, affects its subcellular localization in response to stress: StPDI1 expression is induced by ER-stress and salt. Both proteins, StSUT1 and StPDI1, were found in the detergent resistant membrane (DRM) fraction, and this might affect internalization. Knockdown of StPDI1 expression severely affects abiotic stress tolerance of transgenic potato plants. Analysis of these plants does not reveal modified subcellular localization or endocytosis of StSUT1, but rather a disturbed redox homeostasis, reduced detoxification of reactive oxygen species and effects on primary metabolism. Parallel observations with other StSUT1-interacting proteins are discussed. The redox status in leaves seems to be linked to the sugar status in response to various stress stimuli and to play a role in stress tolerance.


Assuntos
Homeostase , Proteínas de Transporte de Monossacarídeos/fisiologia , Oxirredução , Proteínas de Plantas/fisiologia , Isomerases de Dissulfetos de Proteínas/fisiologia , Sacarose/metabolismo , Clonagem Molecular , Técnicas de Silenciamento de Genes , Homeostase/fisiologia , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase em Tempo Real , Solanum tuberosum/embriologia , Solanum tuberosum/fisiologia , Estresse Fisiológico/fisiologia
2.
Plant J ; 76(5): 849-60, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24118403

RESUMO

Plastid genes are transcribed by two types of RNA polymerases: a plastid-encoded eubacterial-type RNA polymerase (PEP) and nuclear-encoded phage-type RNA polymerases (NEPs). To investigate the spatio-temporal expression of PEP, we tagged its α-subunit with a hemagglutinin epitope (HA). Transplastomic tobacco plants were generated and analyzed for the distribution of the tagged polymerase in plastid sub-fractions, and associated genes were identified under various light conditions. RpoA:HA was detected as early as the 3rd day after imbibition, and was constitutively expressed in green tissue over 60 days of plant development. We found that the tagged polymerase subunit preferentially associated with the plastid membranes, and was less abundant in the soluble stroma fraction. Attachment of RpoA:HA to the membrane fraction during early seedling development was independent of DNA, but at later stages of development, DNA appears to facilitate attachment of the polymerase to membranes. To survey PEP-dependent transcription units, we probed for nucleic acids enriched in RpoA:HA precipitates using a tobacco chloroplast whole-genome tiling array. The most strongly co-enriched DNA fragments represent photosynthesis genes (e.g. psbA, psbC, psbD and rbcL), whose expression is known to be driven by PEP promoters, while NEP-dependent genes were less abundant in RpoA:HA precipitates. Additionally, we demonstrate that the association of PEP with photosynthesis-related genes was reduced during the dark period, indicating that plastome-wide PEP-DNA association is a light-dependent process.


Assuntos
Cloroplastos/enzimologia , DNA de Cloroplastos/genética , RNA Polimerases Dirigidas por DNA/genética , Luz , Membrana Celular/genética , Cloroplastos/genética , Imunoprecipitação da Cromatina , Regulação da Expressão Gênica de Plantas , Fotossíntese/genética , Plantas Geneticamente Modificadas/genética , Nicotiana/genética
3.
Scars Burn Heal ; 3: 2059513117707686, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29799550

RESUMO

For older people (aged over 65 years), the risk of dying in a residential fire is doubled compared to the general population. Obvious causes of death mainly include smoke inhalation and burn injuries. That older people are more fragile and have more concurrent diseases is inherent, but what is it that makes them more vulnerable? It is known that the number of elderly people is increasing globally and that the increased risk of death in fires can be explained, at least in part, by physical and/or cognitive disabilities as well as socioeconomic and behavioural factors. The possibility that medical illnesses and an aging organism/tissues might explain this increased risk has not been shown to the same extent. Therefore, this narrative literature review focuses on medical and biological explanations. An initial search using the terms 'elderly', 'fatal', 'residential' and 'fire' yielded some interesting articles. Using a broader snowball search also accepting grey literature, several additional risk factors could be identified. Cardiovascular diseases, in particular atherosclerotic heart disease, greatly increases the vulnerability to, for example, carbon monoxide and probably also other asphyxiating gases. Cardiovascular diseases and lack of physical fitness may also increase vulnerability to heat. Burned elderly patients are also at a higher risk of death than younger patients, but it is controversial whether it is age itself or the pre-existing illnesses that come with age that increase the risk. Immunosenescence, malnutrition and female gender are other risk factors for poorer outcome after burns, all of which are common among older people.

4.
J Med Chem ; 59(10): 4578-600, 2016 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-27075367

RESUMO

Protein lysine methyltransferases have recently emerged as a new target class for the development of inhibitors that modulate gene transcription or signaling pathways. SET and MYND domain containing protein 2 (SMYD2) is a catalytic SET domain containing methyltransferase reported to monomethylate lysine residues on histone and nonhistone proteins. Although several studies have uncovered an important role of SMYD2 in promoting cancer by protein methylation, the biology of SMYD2 is far from being fully understood. Utilization of highly potent and selective chemical probes for target validation has emerged as a concept which circumvents possible limitations of knockdown experiments and, in particular, could result in an improved exploration of drug targets with a complex underlying biology. Here, we report the development of a potent, selective, and cell-active, substrate-competitive inhibitor of SMYD2, which is the first reported inhibitor suitable for in vivo target validation studies in rodents.


Assuntos
Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Piridazinas/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Células HEK293 , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Modelos Moleculares , Estrutura Molecular , Piridazinas/síntese química , Piridazinas/química , Relação Estrutura-Atividade , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/metabolismo
5.
Artigo em Inglês | MEDLINE | ID: mdl-19688643

RESUMO

Macromastia is a common indication for breast reduction within the public health care system in Sweden. To reduce the waiting time, a project was launched to operate on patients during a three-month period at a local hospital in Stockholm (Nacka Hospital). The operations were done by specialists and residents from the Karolinska University Hospital, using a medial flap technique. The aim of this prospective study was to evaluate the results of this project, focusing on clinical outcome, quality of life, patients' satisfaction, and aesthetic results. Personal and preoperative clinical data and information about risk factors were extracted from the patients' records. At the 6 month follow-up the patients were asked to fill in two questionnaires: "Short Form-36" and another form about patients' satisfaction and sensitivity. Four digital photos taken during the follow-up were graded by three plastic surgeons. Diabetes and oral contraceptives, respectively, were risk factors for infection and delayed wound healing. Patients reported a significantly increased quality of life after six months, regardless of body mass index. Patients were generally more satisfied with the aesthetic outcome than were the surgeons, had satisfactory aesthetic results (89%), acceptable levels of complications (31%), and increased quality of life. The medial flap technique should be evaluated further for its loss of sensitivity.


Assuntos
Mamoplastia/métodos , Satisfação do Paciente , Qualidade de Vida , Retalhos Cirúrgicos , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Mama/cirurgia , Estética , Feminino , Seguimentos , Humanos , Mamoplastia/efeitos adversos , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários , Suécia , Resultado do Tratamento , Cicatrização , Adulto Jovem
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