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1.
J Phys Chem B ; 127(42): 9014-9020, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37819729

RESUMO

We report resonance Raman spectra of the light-harvesting fucoxanthin-chlorophyll a/c-binding proteins (FCPs) of marine diatom Fragilariopsis sp. The Raman shifts in the 15N-isotope-enriched diatom provide the first spectroscopic evidence for the characterization of the Ca-N marker bands and, thus, of the penta- and hexacoordinated states of chlorophylls a/c in the FCPs. Under 405 and 442 nm Raman excitations, all of the marker bands of Chl a/c are observed and the isotope-based assignments provide new information concerning the structure of Chls a/c in the FCPs and their interactions with the protein environment. Therefore, the Raman spectrum at 405 nm originates from the π-π* transitions of Chl a/c and not from a different, non π-π* electronic transition, as previously reported (BBA Bioenergetics, 2010, 1797, 1647-1656). Based on the 15N isotope shifts of the Ca-N and in conjunction with other marker bands, two distinct conformations of five- and six-coordinated Chl a and Chl c are observed. In addition, two keto carbonyls were observed at 1679 (strong H-bonded) and 1691 cm-1 (weak H-bonded) in both the 405 and 442 nm Raman spectra, respectively. Collectively, the results provide solid evidence of the nature of the vibrational modes of the active Chl a/c photosynthetic pigments in the FCPs.


Assuntos
Diatomáceas , Análise Espectral Raman , Clorofila A/metabolismo , Proteínas de Ligação à Clorofila/química , Diatomáceas/química , Clorofila/química , Isótopos , Complexos de Proteínas Captadores de Luz/química
2.
Int J Sports Med ; 43(13): 1084-1096, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35288882

RESUMO

Doxorubicin is an anti-neoplasmic drug that prevents DNA replication but induces senescence and cellular toxicity. Intensive research has focused on strategies to alleviate the doxorubicin-induced skeletal myotoxicity. The aim of the present review is to critically discuss the relevant scientific evidence about the role of exercise and growth factor administration and offer novel insights about newly developed-tools to combat the adverse drug reactions of doxorubicin treatment on skeletal muscle. In the first part, we discuss current data and mechanistic details on the impact of doxorubicin on skeletal myotoxicity. We next review key aspects about the role of regular exercise and the impact of growth factors, administered either pharmacologically or via genetic interventions. Future strategies such as combination of exercise and growth factor administration remain to be established to combat the pharmacologically-induced myotoxicity.


Assuntos
Doxorrubicina , Miotoxicidade , Humanos , Doxorrubicina/toxicidade , Doxorrubicina/metabolismo , Músculo Esquelético/fisiologia , Exercício Físico , Senescência Celular , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo
3.
Exp Physiol ; 106(3): 700-713, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33450106

RESUMO

NEW FINDINGS: What is the central question of this study? What is the impact of obesity-independent hyperlipidaemia on skeletal muscle stem cell function of ApoE-deficient (ApoE-/- ) mice? What is the main finding and its importance? Compromised muscle stem cell function accounts for the impaired muscle regeneration in hyperlipidaemic ApoE-/- mice. Importantly, impaired muscle regeneration is normalised by administration of platelet releasate. ABSTRACT: Muscle satellite cells are important stem cells for skeletal muscle regeneration and repair after injury. ApoE-deficient mice, an established mouse model of hyperlipidaemia and atherosclerosis, show evidence of oxidative stress-induced lesions and fat infiltration in skeletal muscle followed by impaired repair after injury. However, the mechanisms underpinning attenuated muscle regeneration remain to be fully defined. Key to addressing the latter is to understand the properties of muscle stem cells from ApoE-deficient mice and their myogenic potential. Muscle stem cells from ApoE-deficient mice were cultured both ex vivo (on single fibres) and in vitro (primary myoblasts) and their myogenic capacity was determined. Skeletal muscle regeneration was studied on days 5 and 10 after cardiotoxin injury. ApoE-deficient muscle stem cells showed delayed activation and differentiation on single muscle fibres ex vivo. Impaired proliferation and differentiation profiles were also evident on isolated primary muscle stem cells in culture. ApoE-deficient mice displayed impaired skeletal muscle regeneration after acute injury in vivo. Administration of platelet releasate in ApoE-deficient mice reversed the deficits of muscle regeneration after acute injury to wild-type levels. These findings indicate that muscle stem cell myogenic potential is perturbed in skeletal muscle of a mouse model of hyperlipidaemia. We propose that platelet releasate could be a therapeutic intervention for conditions with associated myopathy such as peripheral arterial disease.


Assuntos
Hiperlipidemias , Células Satélites de Músculo Esquelético , Animais , Diferenciação Celular , Proliferação de Células/fisiologia , Camundongos , Desenvolvimento Muscular/fisiologia , Músculo Esquelético/fisiologia , Mioblastos , Regeneração/fisiologia
4.
RSC Adv ; 12(2): 631-639, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35425097

RESUMO

The combined application of the structure sensitive techniques Fourier transform infrared µ-spectroscopy and Raman microscopy in conjunction with different approaches of laser-induced breakdown spectroscopy (LIBS) including the two-color double pulse (DP-LIBS) have been applied towards the characterization of whole ore copper-sulfide minerals. Discrete information from the surface of the whole ore minerals that lead to the establishment of infrared marker bands and from the surface of bioleached samples that allow the monitoring of jarosite and biofilm formation are provided by FTIR mapping experiments. Raman data can provide information related to the type of the mineral and of the secondary minerals formed on the surface of the ore. Of the four different LIBS approaches applied towards the characterization of the composition of the whole ore minerals, the DP-LIBS shows the highest sensitivity with increasing signals for both the Fe and Cu metals in the whole ore samples.

5.
Case Rep Emerg Med ; 2013: 678678, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23984116

RESUMO

The small intestine is the third in frequency intraperitoneal organ which is injured after blunt trauma of the abdomen. In most of the cases, this type of injuries is accompanied by other injuries, which make it more difficult to diagnose. Failure of diagnosis and delay in treating these injuries significantly increase the morbidity and mortality of these patients. Abdominal visceral injuries after flipping the handlebar of the bike are common in children. Such injuries can cause injury to both solid and hollow abdominal viscera. Unlike children, adults' abdominal visceral injuries after flipping the bike's handlebar are extremely rare. A 25-year-old man was admitted to our department due to progressively abdominal pain after an accident with the handlebar of his bike. The subsequent CT scan after per os administration of contrast medium revealed the presence of free intraperitoneal contrast. It is a rare case of jejunal perforation after flipping the handlebar of the bicycle which was treated by partial removal of the injured part of jejunum and end-to-end anastomosis. To the best of our knowledge this is the first time we describe such an injury with this mechanism to an adult.

6.
Case Rep Med ; 2013: 206564, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23864863

RESUMO

In the last thirty years, the widespread use of endoscopic retrograde cholangiopancreatography (ERCP) has radically changed the management of patients with diseases of the extrahepatic biliary tract and pancreas. Pneumothorax is a rare complication of ERCP. We report two cases of pneumothorax following elective ERCP for ductal stone clearance. The first patient was a 45-year-old female, who developed respiratory distress, abdominal pain, and profoundly abdominal distention immediately after the procedure. Imaging studies revealed the presence of a right-side pneumothorax, pneumomediastinum, pneumoperitoneum, and pneumoretroperitoneum. The second patient was a 94-year-old female, who developed tension pneumothorax with clinical signs of shock during the procedure. Imaging studies revealed the presence of a right-side pneumothorax without free air in the mediastinum and retroperitoneal space. The imaging findings suggest that the occurrence of this rare complication in our patients was caused by entirely different pathophysiological mechanisms. Both patients were successfully treated with chest tube insertion, and no further intervention was required. Clinicians should be aware of this serious complication because delayed diagnosis may involve significant morbidity and mortality risks.

7.
Case Rep Oncol Med ; 2013: 243939, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23533870

RESUMO

Malignant hepatic epithelioid hemangioendothelioma (HEHE) is a rare malignant tumor of vascular origin. Nonspecific symptoms and the absence of experience of surgeons, radiologists, and histopathologists due to the rarity of HEHE make the diagnosis of this entity very challenging. Misdiagnosis is not a rare event, and the consequences of such an event are catastrophic. We report a case of a patient suffering from HEHE in which the initial diagnosis was hepatocellular carcinoma (HCC). The presence of normal laboratory values, liver function tests, tumor markers along with the absence of a chronic liver disease, or any other predisposing factors for HCC, was in contrast with the diagnosis of HCC. Clinical suspicion drove us to the repetition of a liver biopsy and the reevaluation of the sample by a more experience histopathology department in liver tumors. The last biopsy confirmed the diagnosis of HEHE, and the patient escaped any unnecessary treatment for a nonexisting HCC.

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