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1.
Postgrad Med J ; 98(1155): 48-56, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33563707

RESUMO

Several studies have documented the synergy between vancomycin/daptomycin and various beta-lactams, and clinical studies have studied this combination therapy in humans. We review the published literature on this topic to know the utility of the combined treatment with beta-lactams in treating bacteraemia methicillin-resistant Staphylococcus aureus (MRSA) infections. Fifteen observational studies, three randomised clinical trials and three systematics reviews are analysed in this article. Observational studies used ceftaroline, cefazolin, piperacillin/tazobactam or cefepime among the beta-lactams. Clinical trials used cloxacillin or flucloxacillin as the most used beta-lactam in two trials and ceftaroline in one. Three systematic reviews are published. One of them only includes studies with vancomycin and included six studies. The other two systematic reviews include patients with daptomycin or vancomycin and included 15 and 9 studies, respectively. Adding a beta-lactam to vancomycin or daptomycin may help shorten bacteraemia and avoid recurrences in patients with MRSA bacteraemia. There is no evidence that combined therapy improves mortality. Nephrotoxicity in clinical trials precludes the use of combination therapy mainly with cloxacillin or flucloxacillin, but systematic reviews have not found a significant difference in this point in observational studies with other beta-lactams. The role of other beta-lactams such as ceftaroline should be thoroughly studied in these patients.


Assuntos
Daptomicina/uso terapêutico , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Vancomicina/uso terapêutico , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Cloxacilina/uso terapêutico , Floxacilina/uso terapêutico , Humanos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , beta-Lactamas/uso terapêutico
2.
Biophys J ; 116(12): 2266-2274, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31155147

RESUMO

The kinesin-3 motor KIF1A is involved in long-ranged axonal transport in neurons. To ensure vesicular delivery, motors need to navigate the microtubule lattice and overcome possible roadblocks along the way. The single-headed form of KIF1A is a highly diffusive motor that has been shown to be a prototype of a Brownian motor by virtue of a weakly bound diffusive state to the microtubule. Recently, groups of single-headed KIF1A motors were found to be able to sidestep along the microtubule lattice, creating left-handed helical membrane tubes when pulling on giant unilamellar vesicles in vitro. A possible hypothesis is that the diffusive state enables the motor to explore the microtubule lattice and switch protofilaments, leading to a left-handed helical motion. Here, we study the longitudinal rotation of microtubules driven by single-headed KIF1A motors using fluorescence-interference contrast microscopy. We find an average rotational pitch of ≃1.5µm, which is remarkably robust to changes in the gliding velocity, ATP concentration, microtubule length, and motor density. Our experimental results are compared to stochastic simulations of Brownian motors moving on a two-dimensional continuum ratchet potential, which quantitatively agree with the fluorescence-interference contrast experiments. We find that single-headed KIF1A sidestepping can be explained as a consequence of the intrinsic handedness and polarity of the microtubule lattice in combination with the diffusive mechanochemical cycle of the motor.


Assuntos
Cinesinas/química , Cinesinas/metabolismo , Modelos Moleculares , Animais , Microtúbulos/metabolismo , Conformação Proteica
4.
Int J Cancer ; 142(4): 792-804, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29044515

RESUMO

Colorectal cancer results from the malignant transformation of colonic epithelial cells. Stromal fibroblasts are the main component of the tumour microenvironment, and play an important role in the progression of this and other neoplasias. Wnt/ß-catenin signalling is essential for colon homeostasis, but aberrant, constitutive activation of this pathway is a hallmark of colorectal cancer. Here we present the first transcriptomic study on the effect of a Wnt factor on human colonic myofibroblasts. Wnt3A regulates the expression of 1,136 genes, of which 662 are upregulated and 474 are downregulated in CCD-18Co cells. A set of genes encoding inhibitors of the Wnt/ß-catenin pathway stand out among those induced by Wnt3A, which suggests that there is a feedback inhibitory mechanism. We also show that the PKP2 gene encoding the desmosomal protein Plakophilin-2 is a novel direct transcriptional target of Wnt/ß-catenin in normal and colon cancer-associated fibroblasts. PKP2 is induced by ß-catenin/TCF through three binding sites in the gene promoter and one additional binding site located in an enhancer 20 kb upstream from the transcription start site. Moreover, Plakophilin-2 antagonizes Wnt/ß-catenin transcriptional activity in HEK-293T cells, which suggests that it may act as an intracellular inhibitor of the Wnt/ß-catenin pathway. Our results demonstrate that stromal fibroblasts respond to canonical Wnt signalling and that Plakophilin-2 plays a role in the feedback control of this effect suggesting that the response to Wnt factors in the stroma may modulate Wnt activity in the tumour cells.


Assuntos
Fibroblastos Associados a Câncer/fisiologia , Neoplasias Colorretais/genética , Placofilinas/genética , Proteína Wnt3A/genética , beta Catenina/genética , Sítios de Ligação , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Dactinomicina/farmacologia , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Células HeLa , Humanos , Células MCF-7 , Regiões Promotoras Genéticas , Fatores de Transcrição TCF/genética , Fatores de Transcrição TCF/metabolismo , Transcrição Gênica , Proteína Wnt3A/metabolismo , beta Catenina/metabolismo
5.
Nano Lett ; 16(8): 5169-75, 2016 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-27434042

RESUMO

We demonstrate a general and robust method to confine on a plane strongly diffusing nanoparticles in water by using size tunable magnetic channels. These virtual conduits are realized with pairs of movable Bloch walls located within an epitaxially grown ferrite garnet film. We show that once inside the magnetic conduit the particles experience an effective local parabolic potential in the transverse direction, while freely diffusing along the conduit. The stiffness of the magnetic potential is determined as a function of field amplitude that varies the width of the magnetic channel. Precise control of the degree of confinement is demonstrated by tuning the applied field. The magnetic conduit is then used to realize single files of nonpassing particles and to induce periodic condensation of an ensemble of particles into parallel stripes in a completely controllable and reversible manner.

6.
Biophys J ; 108(6): 1555-1565, 2015 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-25809268

RESUMO

The development of multicellular organisms involves cells to decide their fate upon the action of biochemical signals. This decision is often spatiotemporally coordinated such that a spatial pattern arises. The dynamics that drive pattern formation usually involve genetic nonlinear interactions and positive feedback loops. These complex dynamics may enable multiple stable patterns for the same conditions. Under these circumstances, pattern formation in a developing tissue involves a selection process: why is a certain pattern formed and not another stable one? Herein we computationally address this issue in the context of the Notch signaling pathway. We characterize a dynamical mechanism for developmental selection of a specific pattern through spatiotemporal changes of the control parameters of the dynamics, in contrast to commonly studied situations in which initial conditions and noise determine which pattern is selected among multiple stable ones. This mechanism can be understood as a path along the parameter space driven by a sequence of biochemical signals. We characterize the selection process for three different scenarios of this dynamical mechanism that can take place during development: the signal either 1) acts in all the cells at the same time, 2) acts only within a cluster of cells, or 3) propagates along the tissue. We found that key elements for pattern selection are the destabilization of the initial pattern, the subsequent exploration of other patterns determined by the spatiotemporal symmetry of the parameter changes, and the speeds of the path compared to the timescales of the pattern formation process itself. Each scenario enables the selection of different types of patterns and creates these elements in distinct ways, resulting in different features. Our approach extends the concept of selection involved in cellular decision-making, usually applied to cell-autonomous decisions, to systems that collectively make decisions through cell-to-cell interactions.


Assuntos
Receptores Notch/metabolismo , Transdução de Sinais , Simulação por Computador , Modelos Moleculares
7.
J Biol Chem ; 288(13): 9428-37, 2013 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-23396967

RESUMO

Dishevelled (Dvl) proteins are intracellular effectors of Wnt signaling that have essential roles in both canonical and noncanonical Wnt pathways. It has long been known that Wnts stimulate Dvl phosphorylation, but relatively little is known about its functional significance. We have previously reported that both Wnt3a and Wnt5a induce Dvl2 phosphorylation that is associated with an electrophoretic mobility shift and loss of recognition by monoclonal antibody 10B5. In the present study, we mapped the 10B5 epitope to a 16-amino acid segment of human Dvl2 (residues 594-609) that contains four Ser/Thr residues. Alanine substitution of these residues (P4m) eliminated the mobility shift induced by either Wnt3a or Wnt5a. The Dvl2 P4m mutant showed a modest increase in canonical Wnt/ß-catenin signaling activity relative to wild type. Consistent with this finding, Dvl2 4Pm preferentially localized to cytoplasmic puncta. In contrast to wild-type Dvl2, however, the P4m mutant was unable to rescue Wnt3a-dependent neurite outgrowth in TC-32 cells following suppression of endogenous Dvl2/3. Earlier work has implicated casein kinase 1δ/ε as responsible for the Dvl mobility shift, and a CK1δ in vitro kinase assay confirmed that Ser(594), Thr(595), and Ser(597) of Dvl2 are CK1 targets. Alanine substitution of these three residues was sufficient to abrogate the Wnt-dependent mobility shift. Thus, we have identified a cluster of Ser/Thr residues in the C-terminal domain of Dvl2 that are Wnt-induced phosphorylation (WIP) sites. Our results indicate that phosphorylation at the WIP sites reduces Dvl accumulation in puncta and attenuates ß-catenin signaling, whereas it enables noncanonical signaling that is required for neurite outgrowth.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Regulação da Expressão Gênica , Fosfoproteínas/fisiologia , Proteínas Wnt/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Alanina/química , Animais , Meios de Cultivo Condicionados , Proteínas Desgrenhadas , Células HEK293 , Humanos , Mutação , Fosfoproteínas/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas/metabolismo , RNA Interferente Pequeno/metabolismo , Ratos , Serina/química , Transdução de Sinais , Treonina/química , Proteína Wnt-5a , Proteína Wnt3A/metabolismo
8.
Soft Matter ; 10(5): 753-9, 2014 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-24837682

RESUMO

We used single-molecule tracking experiments to observe the motion of small hydrophobic fluorescent molecules at the interface between water and a solid surface that exhibited periodic chemical patterns. The dynamics were characterized by non-ergodic, continuous time random walk statistics. The step-size distributions displayed enhanced probability of steps to periodic distances, consistent with theoretical predictions for diffusion in an atomic/molecular scale periodic potential. Surprisingly, this general behavior was observed here for surfaces exhibiting characteristic length scales three orders of magnitude larger than atomic/molecular dimensions, and may provide a new way to understand and control solid-liquid interfacial diffusion for molecular targeting applications.

9.
Cell Death Dis ; 15(4): 301, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684650

RESUMO

Understanding the mechanisms involved in colonic epithelial differentiation is key to unraveling the alterations causing inflammatory conditions and cancer. Organoid cultures provide an unique tool to address these questions but studies are scarce. We report a differentiation system toward enterocytes and goblet cells, the two major colonic epithelial cell lineages, using colon organoids generated from healthy tissue of colorectal cancer patients. Culture of these organoids in medium lacking stemness agents resulted in a modest ultrastructural differentiation phenotype with low-level expression of enterocyte (KLF4, KRT20, CA1, FABP2) and goblet cell (TFF2, TFF3, AGR2) lineage markers. BMP pathway activation through depletion of Noggin and addition of BMP4 resulted in enterocyte-biased differentiation. Contrarily, blockade of the Notch pathway using the γ-secretase inhibitor dibenzazepine (DBZ) favored goblet cell differentiation. Combination treatment with BMP4 and DBZ caused a balanced strong induction of both lineages. In contrast, colon tumor organoids responded poorly to BMP4 showing only weak signals of cell differentiation, and were unresponsive to DBZ. We also investigated the effects of 1α,25-dihydroxyvitamin D3 (calcitriol) on differentiation. Calcitriol attenuated the effects of BMP4 and DBZ on colon normal organoids, with reduced expression of differentiation genes and phenotype. Consistently, in normal organoids, calcitriol inhibited early signaling by BMP4 as assessed by reduction of the level of phospho-SMAD1/5/8. Our results show that BMP and Notch signaling play key roles in human colon stem cell differentiation to the enterocytic and goblet cell lineages and that calcitriol modulates these processes favoring stemness features.


Assuntos
Proteína Morfogenética Óssea 4 , Calcitriol , Proteínas de Transporte , Diferenciação Celular , Colo , Dibenzazepinas , Células Caliciformes , Fator 4 Semelhante a Kruppel , Organoides , Receptores Notch , Transdução de Sinais , Humanos , Organoides/efeitos dos fármacos , Organoides/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proteína Morfogenética Óssea 4/metabolismo , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/citologia , Colo/patologia , Receptores Notch/metabolismo , Transdução de Sinais/efeitos dos fármacos , Calcitriol/farmacologia , Células Caliciformes/efeitos dos fármacos , Células Caliciformes/metabolismo , Dibenzazepinas/farmacologia , Linhagem da Célula/efeitos dos fármacos , Enterócitos/metabolismo , Enterócitos/efeitos dos fármacos , Enterócitos/citologia , Vitamina D/farmacologia
10.
J Biol Chem ; 287(14): 11098-107, 2012 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-22337882

RESUMO

Cross-linking of ligand-engaged cytotoxic T lymphocyte antigen-4 (CTLA-4) to the T cell receptor (TCR) during the early phase of T cell activation attenuates TCR signaling, leading to T cell inhibition. To promote this event, a bispecific fusion protein comprising a mutant mouse CD80 (CD80w88a) and lymphocyte activation antigen-3 was engineered to concurrently engage CTLA-4 and cross-link it to the TCR. Cross-linking is expected to be attained via ligation of CTLA-4 first to MHCII and then indirectly to the TCR, generating a CTLA-4-MHCII-TCR trimolecular complex that forms between T cells and antigen-presenting cells during T cell activation. Treating T cells with this bispecific fusion protein inhibited T cell activation. In addition, it induced the production of IL-10 and TGF-ß and attenuated AKT and mTOR signaling. Intriguingly, treatment with the bispecific fusion protein also directed early T cell differentiation into Foxp3-positive regulatory T cells (Tregs). This process was dependent on the endogenous production of TGF-ß. Thus, bispecific fusion proteins that engage CTLA-4 and co-ligate it to the TCR during the early phase of T cell activation can negatively regulate the T cell response. Bispecific biologics with such dual functions may therefore represent a novel class of therapeutics for immune modulation. These findings presented here also reveal a potential new role for CTLA-4 in Treg differentiation.


Assuntos
Antígeno CTLA-4/metabolismo , Diferenciação Celular , Fatores de Transcrição Forkhead/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/metabolismo , Animais , Comunicação Autócrina/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Antígenos HLA/metabolismo , Camundongos , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Transdução de Sinais/efeitos dos fármacos , Especificidade por Substrato , Linfócitos T Reguladores/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Fator de Crescimento Transformador beta/farmacologia
11.
Cir Esp ; 91(3): 184-8, 2013 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-23228416

RESUMO

OBJECTIVE: Videothoracoscopic (VTC) resection of peripheral pulmonary nodules (PN) occasionally requires performing a mini-thoracotomy to locate them using palpation. The aim of this study is to evaluate the usefulness of inserting a CT-guided harpoon as a method for locating PN prior to surgery. MATERIAL AND METHODS: A study was conducted on a total of 52 patients who were scheduled for locating 55 PN prior to surgery by inserting a CT-guided harpoon, from November 2004 to January 2011. RESULTS: Of the 52 patients, of whom 35 had a history of cancer, 31 were male and 21 were female, with ages between 28 and 84 years (mean: 62.2 years) with a PN <20mm (mean: 9.57mm). A total of 55 harpoons were inserted (3 patients had 2 simultaneous harpoons). Using the VTC it was observed that 52 harpoons were correctly anchored to the PN. There were no complications. In the group of 35 patients with an oncology history, the nodules were malignant in 26 cases (74.3%), and there were 17 (70.6%) with malignant PN in those with no oncology history. The hospital stay varied between 4 and 72h, with 19 patients (36.5%) included in a one-day surgery program. CONCLUSIONS: The preoperative identification of peripheral pulmonary nodules enables them to be removed directly with VTC. The insertion of a CT-guided harpoon in the PN is a safe and effective procedure that can be performed in a one-day surgery program.


Assuntos
Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/patologia , Cirurgia Torácica Vídeoassistida , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia/instrumentação , Biópsia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nódulos Pulmonares Múltiplos/cirurgia , Cuidados Pré-Operatórios , Radiografia Intervencionista , Estudos Retrospectivos
12.
FEBS J ; 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37699548

RESUMO

Colorectal cancer (CRC) is one of the most life-threatening neoplasias in terms of incidence and mortality worldwide. Vitamin D deficiency has been associated with an increased risk of CRC. 1α,25-Dihydroxyvitamin D3 [1,25(OH)2 D3 ], the most active vitamin D metabolite, is a pleiotropic hormone that, through its binding to a transcription factor of the nuclear receptor superfamily, is a major regulator of the human genome. 1,25(OH)2 D3 acts on colon carcinoma and stromal cells and displays tumor protective actions. Here, we review the variety of molecular mechanisms underlying the effects of 1,25(OH)2 D3 in CRC, which affect multiple processes that are dysregulated during tumor initiation and progression. Additionally, we discuss the epidemiological data that associate vitamin D deficiency and CRC, and the most relevant randomized controlled trials of vitamin D3 supplementation conducted in both healthy individuals and CRC patients.

13.
Clin Transl Oncol ; 25(4): 912-932, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36445642

RESUMO

The present document includes consensus-based recommendations from the Brachytherapy Group (GEB) of the Spanish Society of Radiation Oncology (SEOR) and the Spanish Society of Medical Physics (SEFM) for interstitial high-dose-rate (HDR) brachytherapy (BT) for gynaecologic malignancies. A nine-item survey-which included questions on experience with interstitial BT; indications and technique; applicator type; magnetic resonance imaging (MRI)-based planning; dose; fractionation schedule; and treatment planning-was sent to all radiation oncology departments (n = 174) in Spain in 2021. Responses were received from 36 centres (50% of all centres [n = 72] with a BT unit). The consensus-based recommendations presented here are based on a review of the available literature, professional experience among the group of experts, and in-person discussions held during the annual meeting of these two societies. We describe the results of the survey and the following: indications; contraindications; patient selection; description of applicators; role of imaging in planning; contouring; dose prescription; dosimetric reconstruction; optimisation; and dose indications for cancers of the cervix, vagina, and vulva. The various clinical scenarios in which interstitial BT is used in the treatment of gynaecological tumours are described in detail, including cervix intracavitary/interstitial hybrid HDR-BT; cervix perineal templates/freehand implants; primary vaginal malignancies/vaginal recurrences; and vulvar interstitial implants.


Assuntos
Braquiterapia , Neoplasias dos Genitais Femininos , Radioterapia (Especialidade) , Neoplasias do Colo do Útero , Neoplasias Vaginais , Feminino , Humanos , Neoplasias dos Genitais Femininos/radioterapia , Braquiterapia/métodos , Dosagem Radioterapêutica , Física , Planejamento da Radioterapia Assistida por Computador/métodos
14.
Cancers (Basel) ; 15(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37686518

RESUMO

BACKGROUND: The rising incidence of colorectal cancer (CRC) among young patients is alarming. We aim to characterize the clinico-pathological features and outcomes of patients with early-onset CRC (EOCRC), as well as the impacts of COVID-19 pandemic. METHODS: We included all patients with pathologically confirmed diagnoses of CRC at Hospital Universitario La Paz from October 2016 to December 2021. The EOCRC cut-off age was 50 years old. RESULTS: A total of 1475 patients diagnosed with CRC were included, eighty (5.4%) of whom had EOCRC. Significant differences were found between EOCRC and later-onset patients regarding T, N stage and metastatic presentation at diagnosis; perineural invasion; tumor budding; high-grade tumors; and signet ring cell histology, with all issues having higher prevalence in the early-onset group. More EOCRC patients had the RAS/ BRAF wild type. Chemotherapy was administered more frequently to patients with EOCRC. In the metastatic setting, the EOCRC group presented a significantly longer median OS. Regarding the COVID-19 pandemic, more patients with COVID-19 were diagnosed with metastatic disease (61%) in the year after the lockdown (14 March 2020) than in the pre-pandemic EOCRC group (29%). CONCLUSIONS: EOCRC is diagnosed at a more advanced stage and with worse survival features in localized patients. More patients with EOCRC were diagnosed with metastatic disease in the year after the COVID-19 pandemic lockdown. The long-term consequences of COVID-19 are yet to be determined.

15.
Commun Biol ; 5(1): 1157, 2022 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-36310321

RESUMO

Immunization based antibody discovery is plagued by the paucity of antigen-specific B cells. Identifying these cells is akin to finding needle in a haystack. Current and emerging technologies while effective, are limited in terms of capturing the antigen-specific repertoire. We report on the bulk purification of antigen-specific B-cells and the benefits it offers to various antibody discovery platforms. Using five different antigens, we show hit rates of 51-88%, compared to about 5% with conventional methods. We also show that this purification is highly efficient with loss of only about 2% antigen specific cells. Furthermore, we compared clones in which cognate chains are preserved with those from display libraries in which chains either from total B cells (TBC) or antigen-specific B cells (AgSC) underwent combinatorial pairing. We found that cognate chain paired clones and combinatorial clones from AgSC library had higher frequency of functional clones and showed greater diversity in sequence and paratope compared to clones from the TBC library. This antigen-specific B-cell selection technique exemplifies a process improvement with reduced cycle time and cost, by removing undesired clones prior to screening and increasing the chance of capturing desirable and rare functional clones in the repertoire.


Assuntos
Anticorpos , Imunização , Sítios de Ligação de Anticorpos , Biblioteca Gênica , Epitopos
16.
Biotechnol Bioeng ; 108(11): 2611-22, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21618473

RESUMO

Here we describe a method that couples flow cytometric detection with the attenuated translation of a reporter protein to enable efficient selection of CHO clones producing high levels of recombinant proteins. In this system, a small cell surface reporter protein is expressed from an upstream open reading frame utilizing a non-AUG initiation (alternate start) codon. Due to the low translation initiation efficiency of this alternate start codon, the majority of translation initiation events occur at the first AUG of the downstream open reading frame encoding the recombinant protein of interest. While translation of the reporter is significantly reduced, the levels are sufficient for detection using flow cytometric methods and, in turn, predictive of protein expression from the gene of interest since both ORFs are translated from the same mRNA. Using this system, CHO cells have been sorted to obtain enriched pools producing significantly higher levels of recombinant proteins than the starting cell population and clones with significantly better productivity than those generated from limiting dilution cloning. This method also serves as an effective screening tool during clone expansion to enable resources to be focused solely on clones with both high and stable expression.


Assuntos
Códon de Iniciação/genética , Proteínas Recombinantes/biossíntese , Animais , Células CHO , Técnicas de Cultura de Células , Cricetinae , Cricetulus , Citometria de Fluxo , Perfilação da Expressão Gênica/métodos , Genes Reporter , Programas de Rastreamento/métodos , Proteínas Recombinantes/genética
17.
Genes Chromosomes Cancer ; 49(12): 1135-42, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20842728

RESUMO

We evaluate whether 1,25(OH)(2)D(3) downregulates TP73 variants in colon and breast carcinomas, the role of survivin in this context, and the significance of this network in the clinic. Tumor cells were treated/untreated with 1,25(OH)(2)D(3) and transiently transfected with survivin. Levels of survivin and TP73 variants were evaluated by quantitative RT-PCR and Western blotting. In 75 colon and 60 breast cancer patients, the expressions of survivin and TP73 isoforms were determined. Tumor characteristics were examined in each patient. Survivin protein levels were also evaluated in a subgroup of patients and cell lines. Decrease in survivin and TAp73 transcripts and protein and ΔNp73 mRNA was detected after 1,25(OH)(2)D(3) treatment. Ectopic survivin expression led to an increase in the TAp73, ΔNp73, ΔEx2p73, and ΔEx2-3p73 transcripts. In cancer patients, direct correlations were observed between TP73 variants and survivin levels. 1,25(OH)(2)D(3) negatively regulate survivin and TP73 variants in colon and breast cancer cells. Positive regulation of TP73 isoforms by survivin may exist, which reinforces the possibility that the downregulation of TP73 forms by 1,25(OH)(2)D(3) is survivin-dependent.


Assuntos
Neoplasias da Mama/genética , Calcitriol/metabolismo , Calcitriol/farmacologia , Neoplasias do Colo/genética , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Nucleares/genética , Proteínas Supressoras de Tumor/genética , Western Blotting , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Proteínas de Ligação a DNA/metabolismo , Regulação para Baixo , Feminino , Humanos , Proteínas Inibidoras de Apoptose , Masculino , Proteínas Associadas aos Microtúbulos/genética , Proteínas Nucleares/metabolismo , Reação em Cadeia da Polimerase , Prognóstico , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Survivina , Proteína Tumoral p73 , Proteínas Supressoras de Tumor/metabolismo
18.
Cureus ; 13(6): e15658, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34277251

RESUMO

Some solid cancers (such as lung, breast, and esophageal cancer, and melanoma) can lead to pericardial effusion by metastatic spread, potentially provoking hemodynamic instability. Detection by echocardiography is therefore essential. Pericardiocentesis can help restore cardiac function and provide fluid for establishing an etiology through cytological, microbiological, and cellularity analysis. A 60-year-old woman with metabolic syndrome and obesity hypoventilation syndrome presented to the emergency department with dyspnea at rest. A chest X-ray showed cardiomegaly and massive left pleural effusion. Ultrasound findings were pericardial effusion with signs of cardiac tamponade. We performed pericardiocentesis, extracting 1000 mL of exudate, and thoracentesis, which confirmed the diagnosis of lymphocytic exudative effusion. A CAT (computerized tomography) scan of the chest, abdomen, and pelvis revealed a left kidney mass. A biopsy of the mass confirmed the diagnosis of clear cell renal cell carcinoma and a pleural biopsy revealed metastatic involvement. This report describes a rare presentation of cardiac tamponade due to clear cell renal cell carcinoma and discusses the pathogenesis, mechanisms, and prognosis of this condition.

19.
Pathogens ; 10(9)2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34578157

RESUMO

BACKGROUND: Leptospirosis is a worldwide zoonotic infection, and its management needs to be refined. This study aims to discern which antibiotic would be the best option to treat leptospirosis disease and analyze the efficacy of chemoprophylaxis regimens to prevent this illness. METHODS: systematic review and meta-analysis on the efficacy of antibiotic treatment and chemoprophylaxis of leptospirosis in humans. RESULTS: Ten clinical trials compared an antibiotic treatment with placebo or other antibiotic treatments in leptospirosis (the most recent one was published in 2007). The meta-analysis shows no effect of penicillin treatment on mortality compared to placebo (OR 1.65; 95% CI 0.76-3.57; p = 0.21). There are no differences between penicillin and cephalosporins or doxycycline. Penicillin does not reduce the time of defervescence (MD-0.16; 95% CI (-1.4) -1.08; p = 0.80) nor hospital stay (MD 0.15; 95% CI (-0.75)-1.06; p = 0.74). Besides, the data did not demonstrate any effectiveness of the use of penicillin in terms of the incidence of oliguria/anuria, the need for dialysis treatment, time to creatinine normalization, incidence of jaundice, or the liver function normalization time. Eight trials have assessed prophylactic treatment against leptospirosis with different strategies. A weekly dose of 200 mg of doxycycline does not show benefit versus placebo regarding the number of new cases of symptomatic leptospirosis (OR 0.20; 95% CI 0.02-1.87; p = 0.16). A single dose of doxycycline at exposure to flood water could have a beneficial effect (OR 0.23; 95% CI 0.07-0.77; p = 0.02). None of the other chemoprophylaxis regimens tested have shown a statistically significant effect on the number of new symptomatic cases. CONCLUSION: There is no evidence that antibiotics are a better treatment than placebo regarding mortality, shortening of fever, liver and kidney function, or reduction in the hospital stay. On the other hand, neither doxycycline nor penicillin, nor azithromycin have shown statistically significant differences in preventing symptomatic infection. Well-designed clinical trials, including other antibiotics such as quinolones or aminoglycosides, are urgently needed to improve our understanding of the treatment for this infection, which continues to be a neglected disease.

20.
J Contemp Brachytherapy ; 13(2): 135-144, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33897786

RESUMO

PURPOSE: To compare brachytherapy (BT) boost of low-dose-rate (LDR) and high-dose-rate (HDR) techniques in patients diagnosed with intermediate-risk prostate cancer. MATERIAL AND METHODS: Between January 2005 and February 2018, 142 patients (50 LDR and 92 HDR) with intermediate-risk prostate cancer were treated with a BT boost, and retrospectively analyzed. Prescribed dose was 45 Gy with external beam radiotherapy (EBRT) plus 100-108 Gy with LDR-BT, and 60 Gy with EBRT plus one fraction of 10 Gy with HDR-BT. 99% of patients received androgen deprivation therapy (ADT) for 6 months. Primary endpoint was to compare LDR and HDR boosts in terms of biochemical progression-free survival (bPFS). Secondary endpoint, after re-classifying patients into "favorable" and "unfavorable" sub-groups, was to analyze differences with a similar treatment intensity. RESULTS: Median overall follow-up for the total cohort was 66.5 months (range, 16-185 months). There were no significant differences in bPFS, overall survival, cause specific survival, local failure, lymph node failure, or distant failure when LDR or HDR was employed. bPFS at 90 months was 100% for favorable, and 89% and 85% for unfavorable patients at 60 months and 90 months, respectively (log-rank test, p = 0.017). The crude incidence of genitourinary acute and chronic toxicity grade 3 was 0.7% and 4%, respectively. Twelve patients (8%) had chronic rectal hemorrhage grade 2, in whom argon was applied (4 LDR and 8 HDR). CONCLUSIONS: Combined treatment is an excellent therapeutic option in patients with intermediate-risk prostate carcinoma, with similar results in both LDR and HDR approaches and very low toxicities. Importantly, the current literature has indicated that unfavorable-risk patients belong to a different category, and should be treated as patients with high-risk factors. Therefore, the stratification and identification of both risk groups is extremely relevant.

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