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1.
Mil Med ; 188(11-12): e3720-e3725, 2023 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-37099739

RESUMO

Antibiotics and drainage have largely replaced hepatic resection for the treatment of liver abscesses in the modern era; however, in cases caused by a rare strain of Klebsiella pneumoniae with a hypermucoviscous phenotype, more aggressive hepatic resection may be required. The patient is a 34-year-old male who presented to Landstuhl Regional Medical Center with a week of epigastric pain. His workup revealed a 6 cm liver abscess with growth to 10 cm in 48 hours. He underwent multiple drainage procedures at Landstuhl and then was transferred to Walter Reed where further surgical drainage was performed. Initial cultures demonstrated K. pneumoniae. He clinically improved and was able to discharge after a 2 week hospitalization. His final remaining surgical drain was removed as an outpatient, but 48 hours after removal, he was admitted to the intensive care unit in septic shock. Imaging revealed a 12 cm liver abscess, and cultures verified hypermucoviscous Klebsiella. After multidisciplinary discussion and counseling, he underwent an open right partial hepatectomy. Postoperatively he gradually recovered from his sepsis and major operation and then returned to his home in Landstuhl. This is a case of a rare hypermucoviscous variant of K. pneumoniae causing a liver abscess resistant to multiple drainage procedures, ultimately requiring open hepatic surgical resection for source control. This remains a last-resort option in the treatment of liver abscesses and should be considered early when caused by this rare strain of Klebsiella.


Assuntos
Infecções por Klebsiella , Abscesso Hepático , Humanos , Masculino , Adulto , Klebsiella pneumoniae , Hepatectomia , Infecções por Klebsiella/complicações , Infecções por Klebsiella/cirurgia , Abscesso Hepático/cirurgia
2.
Cancers (Basel) ; 14(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36358665

RESUMO

Adrenocortical cancer (ACC) typically presents in advanced stages of disease and has a dismal prognosis. One of the foremost reasons for this is the lack of available systemic therapies, with mitotane remaining the backbone of treatment since its discovery in the 1960s, despite underwhelming efficacy. Surgery remains the only potentially curative option, but about half of patients will recur post-operatively, often with metastatic disease. Other local treatment options have been attempted but are only used practically on a case-by-case basis. Over the past few decades there have been significant advances in understanding the molecular background of ACC, but this has not yet translated to better treatment options. Attempts at novel treatment strategies have not provided significant clinical benefit. This paper reviews our current treatment options and molecular understanding of ACC and the reasons why a successful treatment has remained elusive. Additionally, we discuss the knowledge gaps that need to be overcome to bring us closer to successful treatment and ways to bridge them.

3.
Ann Plast Surg ; 89(4): 408-411, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36149981

RESUMO

BACKGROUND: Large soft tissue defects associated with major limb amputation pose a challenge to the reconstructive surgeon due to the 3-dimensional contour of the residual limb and the need to withstand the unnatural shear forces imparted by prosthetic sockets. Fasciocutaneous flaps based on the circumflex scapular system have proven useful for residual limb coverage due to the durability of the tissue provided, the absence of functional morbidity, and the ease of reelevation. A modified, bilobed flap design that incorporates large Burrow triangles into each limb serves to leverage the perforasome anatomy of the posterior trunk to provide maximal 3-dimensional coverage and favorable flap geometry while also facilitating donor site closure. METHODS: A retrospective medical record review was performed for all patients who underwent reconstruction of a residual limb after major amputation using the modified, bilobed scapular-parascapular free flap design at Walter Reed National Military Medical Center between 2018 and 2021. A computer-based application was used to calculate flap area and dimensions based on photographs of preoperative and intraoperative markings. RESULTS: Six patients with varying amputation levels (2 transtibial, 1 transfemoral, 1 hip-disarticulation, 1 hemipelvectomy, 1 transradial) underwent soft tissue coverage using the modified flap design. Mean flap area was 318.4 cm 2 with 51.1 cm 2 attributable to the modified design. This represents a 16% increase over a conventional bilobed design. There were no partial or complete flap failures. CONCLUSIONS: The modified scapular-parascapular flap design enables harvest of a larger and more versatile fasciocutaneous flap with geometry that is well suited for coverage of the residual limb.


Assuntos
Procedimentos de Cirurgia Plástica , Humanos , Microcirurgia , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Escápula , Retalhos Cirúrgicos
4.
J Agric Food Chem ; 70(30): 9295-9304, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35862501

RESUMO

A major objective in faba bean breeding is to improve its protein quality by selecting cultivars with enhanced desirable physicochemical properties. However, the protein composition of the mature seed is determined by a series of biological processes occurring during seed growth. Thus, any attempt to explain the final seed composition must consider the dynamics of the seed proteome during seed development. Here, we investigated the proteomic profile of developing faba bean seeds across 12 growth stages from 20 days after pollination (DAP) to full maturity. We analyzed trypsin-digested total protein extracts from the seeds at different growth stages by liquid chromatography-tandem mass spectrometry (LC-MS/MS), identifying 1217 proteins. The functional clusters of these proteins showed that, in early growth stages, proteins related to cell growth, division, and metabolism were most abundant compared to seed storage proteins that began to accumulate from 45 DAP. Moreover, label-free quantification of the relative abundance of seed proteins, including important globulin proteins, revealed several distinct temporal accumulation trends among the protein classes. These results suggest that these proteins are regulated differently and require further understanding of the impact of the different environmental stresses occurring at different grain filling stages on the expression and accumulation of these seed storage proteins.


Assuntos
Vicia faba , Cromatografia Líquida , Melhoramento Vegetal , Proteômica , Proteínas de Armazenamento de Sementes/metabolismo , Sementes/química , Espectrometria de Massas em Tandem , Vicia faba/química
5.
Pharmacol Res Perspect ; 8(4): e00635, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32761799

RESUMO

Apocynin has been widely used in vivo as a Nox2-contaninig nicotinamide adenine dinucleotide phosphate oxidase inhibitor. However, its time-dependent tissue distribution and inhibition on organ reactive oxygen species (ROS) production remained unclear. In this study, we examined apocynin pharmacokinetics and pharmacodynamics (PKPD) after intravenous (iv) injection (bolus, 5 mg/kg) of mice (CD1, 12-week). Apocynin was detected using a HPLC coupled to a linear ion-trap tandem mass spectrometer. Apocynin peak concentrations were detected in plasma at 1 minute (5494 ± 400 ng/mL) (t1/2  = 0.05 hours, clearance = 7.76 L/h/kg), in urine at 15 minutes (14 942 ± 5977 ng/mL), in liver at 5 minutes (2853 ± 35 ng/g), in heart at 5 minutes (3161 ± 309 ng/g) and in brain at 1 minute (4603 ± 208 ng/g) after iv injection. These were accompanied with reduction of ROS production in the liver, heart and brain homogenates. Diapocynin was not detected in these samples. Therapeutic effect of apocynin was examined using a mouse model (C57BL/6J) of high-fat diet (HFD, 16 weeks)-induced obesity and accelerated aging. Apocynin (5 mmol/L) was supplied in drinking water during the HFD period and was detected at the end of treatment in the brain (5369 ± 1612 ng/g), liver (4818 ± 1340 ng/g) and heart (1795 ± 1487 ng/g) along with significant reductions of ROS production in these organs. In conclusion, apocynin PKPD is characterized by a short half-life, rapid clearance, good distribution and inhibition of ROS production in major organs. Diapocynin is not a metabolite of apocynin in vivo. Apocynin crosses easily the blood-brain barrier and reduces brain oxidative stress associated with metabolic disorders and aging.


Assuntos
Acetofenonas/farmacologia , Antioxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Acetofenonas/farmacocinética , Envelhecimento/efeitos dos fármacos , Animais , Antioxidantes/farmacocinética , Barreira Hematoencefálica/metabolismo , Simulação por Computador , Dieta Hiperlipídica , Modelos Animais de Doenças , Meia-Vida , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/tratamento farmacológico , Distribuição Tecidual
6.
J Agric Food Chem ; 68(32): 8535-8544, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32678595

RESUMO

Faba bean (Vicia faba L.) holds great importance for human and animal nutrition for its high protein content. However, better understanding of its seed protein composition is required in order to develop cultivars that meet market demands for plant proteins with specific quality attributes. In this study, we screened 35 diverse Vicia faba genotypes by employing the one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (1D SDS-PAGE) method, and 35 major protein bands obtained from three genotypes with contrasting seed protein profiles were further analyzed by mass spectrometry (MS). Twenty-five of these protein bands (MW range: ∼ 9-107 kDa) had significant (p ≤ 0.05) matches to polypeptides in protein databases. MS analysis showed that most of the analyzed protein bands contained more than one protein type and, in total, over 100 proteins were identified. These included major seed storage proteins such as legumin, vicilin, and convicilin, as well as other protein classes like lipoxygenase, heat shock proteins, sucrose-binding proteins, albumin, and defensin. Furthermore, seed protein extracts were separated by size-exclusion high-performance liquid chromatography (SE-HPLC), and percentages of the major protein classes were determined. On average, legumin and vicilin/convicilin accounted for 50 and 27% of the total protein extract, respectively. However, the proportions of these proteins varied considerably among genotypes, with the ratio of legumin:vicilin/convicilin ranging from 1:1 to 1:3. In addition, there was a significant (p < 0.01) negative correlation between the contents of these major fractions (r = -0.83). This study significantly extends the number of identified Vicia faba seed proteins and reveals new qualitative and quantitative variation in seed protein composition, filling a significant gap in the literature. Moreover, the germplasm and screening methods presented here are expected to contribute in selecting varieties with improved protein content and quality.


Assuntos
Proteínas de Plantas/química , Vicia faba/química , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Espectrometria de Massas , Sementes/química
7.
Genes Dev ; 34(9-10): 650-662, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32217664

RESUMO

Telomeres consist of TTAGGG repeats bound by protein complexes that serve to protect the natural end of linear chromosomes. Most cells maintain telomere repeat lengths by using the enzyme telomerase, although there are some cancer cells that use a telomerase-independent mechanism of telomere extension, termed alternative lengthening of telomeres (ALT). Cells that use ALT are characterized, in part, by the presence of specialized PML nuclear bodies called ALT-associated PML bodies (APBs). APBs localize to and cluster telomeric ends together with telomeric and DNA damage factors, which led to the proposal that these bodies act as a platform on which ALT can occur. However, the necessity of APBs and their function in the ALT pathway has remained unclear. Here, we used CRISPR/Cas9 to delete PML and APB components from ALT-positive cells to cleanly define the function of APBs in ALT. We found that PML is required for the ALT mechanism, and that this necessity stems from APBs' role in localizing the BLM-TOP3A-RMI (BTR) complex to ALT telomere ends. Strikingly, recruitment of the BTR complex to telomeres in a PML-independent manner bypasses the need for PML in the ALT pathway, suggesting that BTR localization to telomeres is sufficient to sustain ALT activity.


Assuntos
DNA Topoisomerases Tipo I/metabolismo , Proteínas de Ligação a DNA/metabolismo , RecQ Helicases/metabolismo , Homeostase do Telômero/fisiologia , Telômero/genética , Telômero/metabolismo , Linhagem Celular Tumoral , Células HeLa , Humanos , Transporte Proteico
8.
Front Microbiol ; 11: 561060, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33505362

RESUMO

Lipopeptide biosurfactants produced by Bacillus sp. were assessed regarding their antimicrobial activity against foodborne pathogenic and food spoilage microorganisms. Both Gram-positive and Gram-negative bacteria were found not to be susceptible to these lipopeptides. However, mycosubtilin and mycosubtilin/surfactin mixtures were very active against the filamentous fungi Paecilomyces variotti and Byssochlamys fulva, with minimum inhibitory concentrations (MICs) of 1-16 mg/L. They were also active against Candida krusei, MIC = 16-64 mg/L. Moreover it was found that the antifungal activity of these lipopeptides was not affected by differences in isoform composition and/or purity. Furthermore their cytotoxicity tested on two different cell lines mimicking ingestion and detoxification was comparable to those of approved food preservatives such as nisin. Overall, for the first time here mycosubtilin and mycosubtilin/surfactin mixtures were found to have high antifungal activity against food relevant fungi at concentrations lower than their toxicity level hence, suggesting their application for extending the shelf-life of products susceptible to these moulds. In addition combining nisin with mycosubtilin or mycosubtiliin/surfactin mixtures proved to be an effective approach to produce antimicrobials with broader spectrum of action.

9.
Ugeskr Laeger ; 181(46)2019 Nov 11.
Artigo em Dinamarquês | MEDLINE | ID: mdl-31791463

RESUMO

Persistent postural-perceptual dizziness (PPPD) is a new diagnosis for functional chronic dizziness and included in the new International Classification of Diseases (ICD)-11. The new criteria are positive, specific and make it easier to identify and study functional chronic dizziness. PPPD is a condition triggered by vestibular-, neurological- or psychological conditions. This review examines the symptoms, pathophysiology and treatment of PPPD.


Assuntos
Tontura , Doenças Vestibulares , Tontura/diagnóstico , Humanos , Classificação Internacional de Doenças , Doenças Vestibulares/diagnóstico
10.
Molecules ; 24(8)2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31027188

RESUMO

Pterygoplichthys disjunctivus, locally named the armoured catfish, is a by-catch of tilapia fishing that accounts for up to 80% of total captured fish in the Adolfo Lopez Mateos dam, in Michoacán, México, affecting the economy of its surrounding communities. This invasive fish is discarded by fishermen since native people do not consume it, partly due to its appearance, yet it is rich in protein. The aim of this study was to produce hydrolysates from armoured catfish using food-grade proteases (neutrases HT and PF and alcalase PAL) and investigate the processing conditions (pH and temperature) that lead to a high degree of hydrolysis, antioxidant activity, and Angiotensin I-Converting Enzyme (ACE) Inhibitory activity. No other similar research has been reported on this underutilized fish. The antioxidant activity was measured by three different methods, ABTS, FRAP and ORAC, with relevance to food and biological systems in order to obtain a more comprehensive assessment of the activity. In addition, the main peptide sequences were identified. All enzymes produced hydrolysates with high antioxidant activity. In particular, the protease HT led to the highest antioxidant activity according to the ABTS (174.68 µmol Trolox equivalent/g fish) and FRAP (7.59 mg ascorbic acid equivalent/g fish) methods and almost the same as PAL according to the ORAC method (51.43 µmol Trolox equivalent/g fish). Moreover, maximum activity was obtained at mild pH and temperature (7.5; 50 °C). Interestingly, the ORAC values obtained here were higher than others previously reported for fish hydrolysates and similar to those reported for fruits such as blueberries, apples and oranges. The peptide sequence IEE(E) was present in several peptides in both hydrolysates; this sequence may be partly responsible for the high antioxidant activity, particularly the one based on iron-reducing power. These findings will be relevant to the valorization of other fish/fish muscle discards and could contribute to the production of food supplements and nutraceuticals.


Assuntos
Antioxidantes/química , Hidrolisados de Proteína/química , Inibidores da Enzima Conversora de Angiotensina/química , Animais , Peixes-Gato , Concentração de Íons de Hidrogênio , Hidrólise , Temperatura
12.
Curr Gene Ther ; 2016 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-27809754

RESUMO

The ubiquitous chromatin opening element from the human HNRPA2B1-CBX3 housekeeping gene locus (A2UCOE) is able to provide stable and cell-to-cell reproducible levels of transgene expression regardless of target cell genome integration site with efficacy demonstrated in adult, embryonic and induced pluripotent stem cells and their differentiated progeny in vitro and in vivo. Here we evaluate the ability of A2UCOE-based lentiviral vectors to confer stable expression following pre-natal delivery in mice. Our results show stable post-natal A2UCOE-eGFP and A2UCOE-luciferase lentiviral vector presence in both the liver and haematopoietic system with concomitant persistence of expression demonstrating efficient transduction of both fetal hepatocytes and haematopoietic stem cells. In addition, we find that an A2UCOE-FIX lentiviral vector produces comparable amounts of plasma FIX protein to that obtained from a SFFV-FIX construct. Furthermore, the A2UCOE-FIX vector shows that at a low (0.19) average vector copy number per liver cell, it can provide stable levels of plasma FIX production, which would convert severe haemophilia B ("pii">CGT-EPUB-lt;1%) to a mild phenotype (≈20%). Our results provide proof-of-principle for low dose pre-natal A2UCOE-based LV delivery to the liver as a therapeutic option for haemophilia B and potentially other metabolic conditions.

13.
Yeast ; 29(10): 425-34, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22968950

RESUMO

The ability to regulate the expression of a gene greatly aids the process of uncovering its functions. The fission yeast Schizosaccharomyces pombe has so far lacked a system for rapidly controlling the expression of chromosomal genes, hindering its full potential as a model organism. Although the widely used nmt1 promoter displays a wide dynamic range of activity, it takes > 14-15 h to derepress. The urg1 promoter also shows a large dynamic range and can be induced quickly (< 2 h), but its implementation requires laborious strain construction and it cannot be used to study meiosis. To overcome these limitations, we constructed a tetracycline-regulated system for inducible expression of chromosomal genes in fission yeast, which is easily established and implemented. In this system the promoter of a gene is replaced by simple one-step substitution techniques with a tetracycline-regulated promoter cassette (tetO(7) -TATA(CYC1) ) in cells where TetR/TetR'-based transcription activators/repressors are also produced. Using top1 and nse6 as reporter genes, we show that Top1 and Nse6 appear after just 30 min of activating tetO(7) -TATA(CYC1) and plateau after -4-6 h. The amount of synthesised protein is comparable to that produced from the attenuated nmt1 promoter P(nmt8) , which should be closer to wild-type levels for most genes than those generated from excessively strong promoters and can be controlled by changing the concentration of the effector antibiotic. This system also works efficiently during meiosis, thus making it a useful addition to the toolkit of the fission yeast community.


Assuntos
Regulação Fúngica da Expressão Gênica/genética , Regiões Promotoras Genéticas/efeitos dos fármacos , Schizosaccharomyces/genética , Tetraciclina/farmacologia , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Genes Fúngicos , Genes Reporter , Vetores Genéticos , Meiose/genética , Fenótipo , Regiões Promotoras Genéticas/genética , Proteínas de Schizosaccharomyces pombe/genética
14.
Biochem J ; 438(3): 535-43, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21749319

RESUMO

The PRKs [protein kinase C-related kinases; also referred to as PKNs (protein kinase Ns)] are a kinase family important in diverse functions including migration and cytokinesis. In the present study, we have re-evaluated and compared the specificity of PKN1 and PKN3 and assessed the predictive value in substrates. We analysed the phosphorylation consensus motif of PKNs using a peptide library approach and demonstrate that both PKN1 and PKN3 phosphorylate serine residues in sequence contexts that have an arginine residue in position -3. In contrast, PKN1 and PKN3 do not tolerate arginine residues in position +1 and -1 respectively. To test the predictive value of this motif, site analysis was performed on the PKN substrate CLIP-170 (cytoplasmic linker protein of 170 kDa); a PKN target site was identified that conformed to the predicted pattern. Using a protein array, we identified 22 further substrates for PKN1, of which 20 were previously undescribed substrates. To evaluate further the recognition signature, the site on one of these hits, EGFR (epidermal growth factor receptor), was identified. This identified Thr654 in EGFR as the PKN1 phosphorylation site and this retains an arginine residue at the -3 position. Finally, the constitutive phosphorylation of EGFR on Thr654 is shown to be modulated by PKN in vivo.


Assuntos
Proteína Quinase C/química , Motivos de Aminoácidos , Receptores ErbB/química , Receptores ErbB/metabolismo , Humanos , Cinética , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Fosforilação , Proteína Quinase C/metabolismo , Especificidade por Substrato
15.
J Biol Chem ; 285(22): 17065-76, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20308064

RESUMO

The S6 kinases (S6Ks) have been linked to a number of cellular processes, including translation, insulin metabolism, cell survival, and RNA splicing. Signaling via the phosphotidylinositol 3-kinase and mammalian target of rapamycin (mTOR) pathways is critical in regulating the activity and subcellular localization of S6Ks. To date, nuclear functions of both S6K isoforms, S6K1 and S6K2, are not well understood. To better understand S6K nuclear roles, we employed affinity purification of S6Ks from nuclear preparations followed by mass spectrometry analysis for the identification of novel binding partners. In this study, we report that in contrast to S6K1, the S6K2 isoform specifically associates with a number of RNA-binding proteins, including heterogeneous ribonucleoproteins (hnRNPs). We focused on studying the mechanism and physiological relevance of the S6K2 interaction with hnRNP F/H. Interestingly, the S6K2-hnRNP F/H interaction was not affected by mitogenic stimulation, whereas mTOR binding to hnRNP F/H was induced by serum stimulation. In addition, we define a new role of hnRNP F in driving cell proliferation, which could be partially attenuated by rapamycin treatment. S6K2-driven cell proliferation, on the other hand, could be blocked by small interfering RNA-mediated down-regulation of hnRNP F. These results demonstrate that the specific interaction between mTOR and S6K2 with hnRNPs is implicated in the regulation of cell proliferation.


Assuntos
Ribonucleoproteínas Nucleares Heterogêneas Grupo F-H/química , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Regulação para Baixo , Regulação Enzimológica da Expressão Gênica , Humanos , Mitógenos/química , Modelos Biológicos , Ligação Proteica , Isoformas de Proteínas , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Sirolimo/química
16.
FEBS Lett ; 581(18): 3377-81, 2007 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-17603046

RESUMO

Protein kinase C delta (PKCdelta) is a Ser/Thr kinase which regulates numerous cellular processes, including proliferation, differentiation, migration and apoptosis. Here, we demonstrate that PKCdelta undergoes in vitro autophosphorylation at three sites within its V3 region (S299, S302, S304), each of which is unique to this PKC isoform and evolutionarily conserved. We demonstrate that S299 and S304 can be phosphorylated in mammalian cells following phorbol ester stimulation and that S299-phosphorylated PKCdelta is localised to both the plasma and nuclear membranes. These data indicate that PKCdelta is phosphorylated upon activation and that phospho-S299 represents a useful marker of the activated enzyme.


Assuntos
Proteína Quinase C-delta/metabolismo , Sequência de Aminoácidos , Animais , Biomarcadores , Linhagem Celular , Chlorocebus aethiops , Sequência Conservada , Ativação Enzimática/efeitos dos fármacos , Humanos , Dados de Sequência Molecular , Fosforilação , Fosfosserina/metabolismo , Proteína Quinase C-delta/química , Proteína Quinase C-delta/genética , Alinhamento de Sequência , Acetato de Tetradecanoilforbol/farmacologia
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