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1.
Artigo em Inglês | MEDLINE | ID: mdl-38651633

RESUMO

Background: The aim of the present study was to describe the presence of co-infection by Toxoplasma gondii and Neospora caninum in goats reared in extensive systems from Mexico. Materials and Methods: A cross-sectional study was conducted to determine the frequency of T. gondii and N. caninum, by detecting antibodies to each parasite by mean commercial ELISA kits. A total of 176 blood samples were randomly collected from mature females reared in extensive system herds from 20 municipalities of state of Guanajuato, Mexico. Results: The general seroprevalence was 23.9 and 21.0% for T. gondii and N. caninum, respectively, while co-infection rate was 3.6%. For geographic and environmental variables, no differences were observed among T. gondii and coinfection; however, it was observed that altitude, annual precipitation, annual average temperature, and rainy period showed significant differences with N. caninum seropositive goats. Conclusion: The seroprevalence of both parasites was appreciated in most of the studied herds. The present study is the first report of T. gondii and N. caninum co-infection in goats from extensive herds in Mexico.

2.
JAMA Ophthalmol ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38512246

RESUMO

Importance: Evaluation of the microbiological diagnostic profile of multidrug-resistant Pseudomonas aeruginosa keratitis and potential management with rose bengal-photodynamic antimicrobial therapy (RB-PDAT) is important. Objective: To document the disease progression of carbapenemase-resistant P aeruginosa keratitis after an artificial tear contamination outbreak. Design, Setting, and Participants: This retrospective observation case series included 9 patients 40 years or older who presented at Bascom Palmer Eye Institute and had positive test results for multidrug-resistant P aeruginosa keratitis between January 1, 2022, and October 31, 2023. Main Outcomes and Measures: Evaluation of type III secretion phenotype, carbapenemase-resistance genes blaGES and blaVIM susceptibility to antibiotics, and in vitro and in vivo outcomes of RB-PDAT against multidrug-resistant P aeruginosa keratitis. Results: Among the 9 patients included in the analysis (5 women and 4 men; mean [SD] age, 73.4 [14.0] years), all samples tested positive for exoU and carbapenemase-resistant blaVIM and blaGES genes. Additionally, isolates were resistant to carbapenems as indicated by minimum inhibitory concentration testing. In vitro efficacy of RB-PDAT indicated its potential application for treating recalcitrant cases. These cases highlight the rapid progression and challenging management of multidrug-resistant P aeruginosa. Two patients were treated with RB-PDAT as an adjuvant to antibiotic therapy and had improved visual outcomes. Conclusions and Relevance: This case series highlights the concerning progression in resistance and virulence of P aeruginosa and emphasizes the need to explore alternative therapies like RB-PDAT that have broad coverage and no known antibiotic resistance. The findings support further investigation into the potential effects of RB-PDAT for other multidrug-resistant microbes.

3.
Comput Biol Med ; 171: 108163, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38417382

RESUMO

SARS-CoV-2 must bind its principal receptor, ACE2, on the target cell to initiate infection. This interaction is largely driven by the receptor binding domain (RBD) of the viral Spike (S) protein. Accordingly, antiviral compounds that can block RBD/ACE2 interactions can constitute promising antiviral agents. To identify such molecules, we performed a virtual screening of the Selleck FDA approved drugs and the Selleck database of Natural Products using a multistep computational procedure. An initial set of candidates was identified from an ensemble docking process using representative structures determined from the analysis of four 3 µ s molecular dynamics trajectories of the RBD/ACE2 complex. Two procedures were used to construct an initial set of candidates including a standard and a pharmacophore guided docking procedure. The initial set was subsequently subjected to a multistep sieving process to reduce the number of candidates to be tested experimentally, using increasingly demanding computational procedures, including the calculation of the binding free energy computed using the MMPBSA and MMGBSA methods. After the sieving process, a final list of 10 candidates was proposed, compounds which were subsequently purchased and tested ex-vivo. The results identified estradiol cypionate and telmisartan as inhibitors of SARS-CoV-2 entry into cells. Our findings demonstrate that the methodology presented here enables the discovery of inhibitors targeting viruses for which high-resolution structures are available.


Assuntos
COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Humanos , Simulação de Acoplamento Molecular , Reposicionamento de Medicamentos/métodos , Enzima de Conversão de Angiotensina 2 , Simulação de Dinâmica Molecular , Ligação Proteica
4.
Res Sq ; 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38352587

RESUMO

Background: Negative dysphotopsias (ND) are visual aberrations associated with in-the-bag optic intraocular lens (IOL) placement, causing arc-shaped or linear shadows. Reverse optic capture (ROC) is employed to prevent ND, yet it poses the risk of posterior capsular opacification (PCO) which usually develops within 2-5 years post-surgery due to the lens epithelial cells (LECs) proliferation and migration onto the posterior capsule. This can lead to a cloudy or hazy appearance in the visual field. Early identification of posterior capsular opacities is crucial to ensure timely intervention and minimize visual impairment. Cases Presentations: Two cases of acute and rapidly progressive PCO following cataract extraction (CE) and IOL placement using the ROC technique to prevent ND are reported at the Bascom Palmer Eye Institute. At the two-week postoperative follow-up, both patients reported a significant progressive decrease in vision in the treated eye, and severe posterior capsular opacities were observed. A diagnosis of PCO was confirmed, and successful visual rehabilitation was achieved through the performance of ND:YAG laser capsulotomy without complications. This case series represents the first reported instances of patients developing PCO within two weeks of CE and IOL placement using the ROC technique. Conclusions: This case series sheds light on the occurrence of posterior capsular opacities shortly after CE and IOL placement using the ROC technique. It highlights the importance of preoperative patient education, postoperative monitoring, and prompt management of potential complications in cataract surgery.

5.
Int J Biol Macromol ; 255: 127843, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37956803

RESUMO

Bombesin is an endogenous peptide involved in a wide spectrum of physiological activities ranging from satiety, control of circadian rhythm and thermoregulation in the central nervous system, to stimulation of gastrointestinal hormone release, activation of macrophages and effects on development in peripheral tissues. Actions of the peptide are mediated through the two high affinity G-protein coupled receptors BB1R and BB2R. Under pathophysiological conditions, these receptors are overexpressed in many different types of tumors, such as prostate cancer, breast cancer, small and non-small cell lung cancer and pancreatic cancer. This observation has been used for designing cell markers, but it has not been yet exploited for therapeutical purposes. Despite the enormous biological interest of the peptide, little is known about the stereochemical features that contribute to their activity. On the one hand, mutagenesis studies identified a few receptor residues important for high bombesin affinity and on the other, a few studies focused on the relevance of diverse residues of the peptide for receptor activation. Models of the peptide bound to BB1R and BB2R can be helpful to improve our understanding of the stereochemical features granting bombesin activity. Accordingly, the present study describes the computational process followed to construct such models by means of Steered Molecular Dynamics, using models of the peptide and its receptors. Present results provide new insights into the structure-activity relationships of bombesin and its receptors, as well as render an explanation for the differential binding affinity observed towards BB1R and BB2R. Finally, these models can be further exploited to help for designing novel small molecule peptidomimetics with improved pharmacokinetics profile.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Masculino , Humanos , Bombesina/química , Bombesina/metabolismo , Receptores da Bombesina/metabolismo , Peptídeos
6.
Cornea ; 43(2): 265-268, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37603688

RESUMO

PURPOSE: The aim of this study was to describe a combined surgical approach for ocular surface and visual rehabilitation in patients with limbal stem cell deficiency, corneal scarring, and cataract. We aimed to introduce this combined approach as an alternative to a staged approach and to describe the intraoperative use of a diamond ophthalmic burr (DOB) and optical coherence tomography (OCT) to achieve and confirm a smooth graft-host interface during the anterior lamellar keratoplasty (ALK) portion of the procedure. METHODS: The quintuple procedure described herein consists of a modified ALK, cataract extraction, intraocular lens implantation, simple limbal epithelial transplantation, and temporal tarsorrhaphy. Intraoperative OCT and DOB were used to guide the creation of the stromal bed during the ALK. The procedure was performed in a patient with limbal stem cell deficiency and corneal scarring after a chemical ocular burn. RESULTS: The tarsorrhaphy was removed at 3 months postoperatively once complete corneal epithelialization was observed. The best-corrected visual acuity improved from light perception preoperatively to 20/30 at 16 months postoperatively with the use of scleral contact lenses. At this postoperative time point, the cornea was clear and compact, and the ocular surface was stable. CONCLUSIONS: The quintuple procedure allowed for visual and ocular surface rehabilitation in cases in which follow-up for a staged approach was not possible. Intraoperative OCT allowed for real-time visualization and dissection of the stromal bed, whereas the use of the DOB helped achieve a smooth stromal surface for an optimal graft-host interface.


Assuntos
Doenças da Córnea , Lesões da Córnea , Transplante de Córnea , Deficiência Límbica de Células-Tronco , Humanos , Cicatriz/cirurgia , Acuidade Visual , Córnea/cirurgia , Lesões da Córnea/cirurgia , Receptores Proteína Tirosina Quinases , Transplante de Córnea/métodos , Doenças da Córnea/cirurgia
7.
Materials (Basel) ; 16(22)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38005097

RESUMO

This research analyses how different cement mortars behave in terms of their physical and mechanical properties. Several components were necessary to make seven mixes of mortars, such as Portland cement, standard sand, and solid waste from a factory of sodium silicate, in addition to graphene oxide. Furthermore, graphene oxide (GO) was selected to reduce the micropores and increase the nanopores in the cement mortar. Hence, some tests were carried out to determine their density, humidity content, water absorption capacity, open void porosity, the alkali-silica reaction, as well as flexural and mechanical strength and acid resistance. Thus, standard-sand-manufactured mortars' mechanical properties were proved to be slightly better than those manufactured with recycled waste; the mortars with this recycled aggregate presented problems of alkali-silica reaction. In addition, GO (in a ratio GO/cement = 0.0003) performed as a filler, improving the mechanical properties (30%), alkali-silica (80%), and acid resistance.

8.
J Chem Inf Model ; 63(20): 6412-6422, 2023 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-37824186

RESUMO

Mutants of Ras are oncogenic drivers of a large number of human tumors. Despite being recognized as an attractive target for the treatment of cancer, the high affinity for its substrate tagged the protein as undruggable for a few years. The identification of cryptic pockets on the protein surface gave the opportunity to identify molecules capable of acting as allosteric modulators. Several molecules were disclosed in recent years, with sotorasib and adagrasib already approved for clinical use. The present study makes use of computational methods to characterize eight prospective allosteric pockets (P1-P8) in K-Ras, four of which (P1-P4) were previously characterized in the literature. The present study also describes the results of a virtual screening study focused on the discovery of hit compounds, binders of the P4 site that can be considered as peptidomimetics of a fragment of the SOS αI helix, a guanine exchange factor of Ras. After a detailed description of the computational procedure followed, we disclose five hit compounds, prospective binders of the P4 allosteric site that exhibit an inhibitory capability higher than 30% in a cell proliferation assay at 50 µM.


Assuntos
Neoplasias , Proteínas , Humanos , Sítio Alostérico , Estudos Prospectivos , Neoplasias/tratamento farmacológico
9.
Microorganisms ; 11(7)2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37512911

RESUMO

Despite the universal vaccination program, there are still regions and territories with a high prevalence of Hepatitis B Virus infection (HBV), such as the Amazon basin, where several indigenous communities live. Additionally, Hepatitis Delta Virus (HDV) is a defective that requires the hepatitis B surface antigen (HBsAg) for the assembly and release of de novo viral particles. Therefore, hepatitis D could be the result of HBV/HDV coinfection or HDV superinfection in individuals with chronic hepatitis B. Among the high prevalence HDV populations are indigenous communities of America. This study aims to describe and characterize the frequency of HBV and HDV infection, viral genotypes and HBV immune escape mutants in indigenous populations from different regions of Colombia. The diagnosis of hepatitis B and hepatitis D was confirmed by serological markers. Moreover, the HBV and HDV genome were amplified by PCR and RT-PCR, respectively, and, subsequently, the phylogenetic analysis was performed. We characterized 47 cases of chronic hepatitis B, 1 case of reactivation and 2 cases of occult hepatitis B infection (OBI). Furthermore, a high prevalence of HDV infection was identified in the study population (29.33%, 22/75) and the circulation of several HBV genotypes and subgenotypes (F1b, F3, F4, and D). Interestingly, this is the first report of the HDV genotype I circulation in this country. These findings demonstrated that HBV and HDV infections are still public health problems in indigenous communities in Colombia.

10.
PLoS One ; 18(7): e0288504, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37440509

RESUMO

Antimicrobial resistance (AMR) represents a serious threat to global health. The development of new drugs to combat infections caused by bacteria resistant to multiple or even all available antibiotics is urgent. Most antibiotics used up to date have been identified from soil microorganisms. The marine environment represents an alternative source with great potential for the identification of microorganisms that produce bioactive molecules, including antibiotics. In this study, we analyzed the antibacterial activity of a collection of 82 bacterial strains isolated from marine water and sediment samples collected from the Southwestern Gulf of Mexico. Eight of the marine isolates inhibited the growth of different pathogenic bacteria, seven of which were identified as presumptive Pseudomonas aeruginosa. Interestingly, genome sequencing and phylogenetic analysis revealed that the remaining marine isolate showing antibacterial activity is a novel Pseudomonas species that we denominated Pseudomonas sp. GOM7, which was not pathogenic in the Galleria mellonella infection model in the conditions tested. Notably, Pseudomonas sp. GOM7 inhibited the growth of multidrug and methicillin-resistant strains of the priority pathogen Staphylococcus aureus. Our results show that the anti-S. aureus compound(s) produced by Pseudomonas sp. GOM7 can be extracted from the culture supernatant of this bacterium with the organic solvent ethyl acetate. Annotation of the Pseudomonas sp. GOM7 genome revealed the presence of several biosynthetic gene clusters predicted to code for possible antimicrobial compounds. Our results further highlight the potential of bacteria from the Gulf of Mexico as a source of novel antimicrobials.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Staphylococcus aureus , Staphylococcus aureus/genética , Pseudomonas/genética , Staphylococcus aureus Resistente à Meticilina/genética , Filogenia , Antibacterianos/farmacologia , Pseudomonas aeruginosa/genética , Bactérias , Genômica , Testes de Sensibilidade Microbiana
11.
Oecologia ; 202(2): 239-250, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37253787

RESUMO

The general assumption that the survival patterns of tropical and southern temperate birds are similar lacks empirical data from higher latitudes. Regional comparisons of New World species are rare, and this assumption has been based on data from African studies. Here, we estimate the survival rates of 88 tropical and southern temperate bird populations (69 species) from eight localities in South America to evaluate the hypothesis that the survival of these populations is homogeneous at the regional scale. We estimated survival based on the Cormack-Jolly-Seber model and compared values from different environments. The survival estimates ranged from 0.30 to 0.80 (0.56 ± 0.12). Apparent survival did not differ significantly between low-latitude tropical environments (03°S) and the other sites from high-latitudes (between 22° and 34°S). Despite a predicted positive trend, body size was not significantly related to survival among passerines. On the other hand, phylogenetic relationships explained more than a third of the variation in bird survival. Based on the largest available database on South American bird species, our findings support the hypothesis that bird survival is homogeneous, at the regional scale, along the southern hemisphere. In particular, we reinforce the hypothesis that climatic variation has a limited influence on bird survival in the southern hemisphere.


Assuntos
Clima Tropical , Filogenia , América do Sul , Tamanho Corporal
12.
J Chem Inf Model ; 63(11): 3544-3556, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-37226335

RESUMO

Bak is a pro-apoptotic protein and a member of the Bcl-2 family that plays a key role in apoptosis, a programmed cell death mechanism of multicellular organisms. Its activation under death stimuli triggers the permeabilization of the mitochondrial outer membrane that represents a point of no return in the apoptotic pathway. This process is deregulated in many tumors where Bak is inactivated, whereas in other cases like in neurodegeneration, it exhibits an excessive response leading to disorders such as the Alzheimer disease. Members of the Bcl-2 family share a common 3D structure, exhibiting an extremely similar orthosteric binding site, a place where both pro and antiapoptotic proteins bind. This similarity raises a selectivity issue that hampers the identification of new drugs, capable of altering Bak activation in a selective manner. An alternative activation site triggered by antibodies has been recently identified, opening the opportunity to undertake new drug discovery studies. Despite this recent identification, an exhaustive study to identify cryptic pockets as prospective allosteric sites has not been yet performed. Thus, the present study aims to characterize novel hotspots in the Bak structure. For this purpose, we have carried out extensive molecular dynamics simulations using three different Bak systems including Bak in its apo form, Bak in complex with its endogen activator Bim and an intermediate form, set up by removing Bim from the previous complex. The results reported in the present work shed some light on future docking studies on Bak through the identification of new prospective allosteric sites, not previously described in this protein.


Assuntos
Simulação de Dinâmica Molecular , Proteína Killer-Antagonista Homóloga a bcl-2 , Proteína 11 Semelhante a Bcl-2/metabolismo , Sítio Alostérico , Estudos Prospectivos , Proteína Killer-Antagonista Homóloga a bcl-2/química , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteínas Reguladoras de Apoptose/química , Proteínas Reguladoras de Apoptose/metabolismo , Apoptose
13.
Foods ; 12(8)2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37107361

RESUMO

The quality of wine grapes and wine depends on their content of phenolic compounds. Under commercial conditions, the phenolic maturity of grapes is mostly achieved by applying abscisic acid analogues. Some Ca forms represent a cost-effective alternative for these compounds. In this study, 'Shiraz' vines (veraison of 90%) were sprayed with CaCO3-rich residues from the cement industry (4.26 g of Ca per L). Fruit from treated and untreated vines was harvested 45 days after CaCO3 spraying and evaluated for quality. The fruit was vinified, and the obtained wines were bottled and stored in darkness for 15 months at 20 °C. Wines were evaluated for quality after storage. The evaluation of grape and wine quality included the content of phenolic compounds and antioxidant capacity. The treatment with CaCO3 did not affect the ripening rate of grapes. However, the treatment improved the fruit yield as well as the color development, the content of phenolic compounds, and antioxidant capacity of grapes and wine. The treatment favored especially the accumulation of malvidin-3-O-glucoside, pelargonidin-3-O-glucoside, caftaric acid, caffeic acid, trans-cinnamic acid, quercetin, catechin, epicatechin, resveratrol, and the procyanidins B1 and B2. Wine made with treated fruit was of higher quality than that of control fruit.

14.
Acta Neurochir (Wien) ; 165(7): 1781-1790, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37014451

RESUMO

BACKGROUND: Classically, the torcular Herophili is described as the symmetric junction between the superior sagittal sinus (SSS), transverse sinuses (TSs), and straight sinus (SS). However, finding this pattern in practice is not standard. Anatomical variations are common, and different drainage patterns should be expected. Existing literature proposes highly detailed descriptions and classifications of this region. Still, a simplified and practical categorization is not available. METHODS: We present an anatomical finding of the torcular Herophili discovered on a cadaveric dissection. Then, we conducted a retrospective study examining the 100 most recent cranial magnetic resonance venographies (MRVs) from the Mayo Clinic, labeling them with a new proposed dural sinus classification system. Images were initially classified by two authors and further validated by a board-certified neurosurgeon and a board-certified neuroradiologist from our institution. To measure consistency in image identification, two additional international neurosurgeons were asked to classify a subset of the same MRV images, and their answers were compared. RESULTS: Of the MRV cohort, 33 patients were male and 67 were female. Their ages ranged from 18 to 86 years, with a mean of 47.35 years and a median of 49 years. Upon examination, 53 patients presented as confluent (53%), 9 as SSS divergent (9%), 25 as SS divergent (25%), 11 as circular (11%), and 2 as trifurcated (2%). The inter-rater reliability ranked very good; agreement between the two neurosurgeons was 83% (κ = 0.830, p < 0.0005). CONCLUSION: The confluence of the venous sinuses is a highly variable anatomical area that is rarely evaluated with neuroimaging before surgery. The classic textbook configuration is not the rule. Using a simplified classification system may increase awareness and hopefully patient safety by preparing the physician for anatomical variations that they will encounter in a surgical or clinical scenario.


Assuntos
Cavidades Cranianas , Seios Transversos , Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Estudos Retrospectivos , Reprodutibilidade dos Testes , Cavidades Cranianas/diagnóstico por imagem , Seios Transversos/diagnóstico por imagem , Seios Transversos/anatomia & histologia , Seio Sagital Superior/diagnóstico por imagem
15.
Pharmaceuticals (Basel) ; 16(4)2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37111342

RESUMO

Over 750 million cases of COVID-19, caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), have been reported since the onset of the global outbreak. The need for effective treatments has spurred intensive research for therapeutic agents based on pharmaceutical repositioning or natural products. In light of prior studies asserting the bioactivity of natural compounds of the autochthonous Peruvian flora, the present study focuses on the identification SARS-CoV-2 Mpro main protease dimer inhibitors. To this end, a target-based virtual screening was performed over a representative set of Peruvian flora-derived natural compounds. The best poses obtained from the ensemble molecular docking process were selected. These structures were subjected to extensive molecular dynamics steps for the computation of binding free energies along the trajectory and evaluation of the stability of the complexes. The compounds exhibiting the best free energy behaviors were selected for in vitro testing, confirming the inhibitory activity of Hyperoside against Mpro, with a Ki value lower than 20 µM, presumably through allosteric modulation.

16.
Sci Adv ; 9(11): eade2175, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36921044

RESUMO

Mutations of the androgen receptor (AR) associated with prostate cancer and androgen insensitivity syndrome may profoundly influence its structure, protein interaction network, and binding to chromatin, resulting in altered transcription signatures and drug responses. Current structural information fails to explain the effect of pathological mutations on AR structure-function relationship. Here, we have thoroughly studied the effects of selected mutations that span the complete dimer interface of AR ligand-binding domain (AR-LBD) using x-ray crystallography in combination with in vitro, in silico, and cell-based assays. We show that these variants alter AR-dependent transcription and responses to anti-androgens by inducing a previously undescribed allosteric switch in the AR-LBD that increases exposure of a major methylation target, Arg761. We also corroborate the relevance of residues Arg761 and Tyr764 for AR dimerization and function. Together, our results reveal allosteric coupling of AR dimerization and posttranslational modifications as a disease mechanism with implications for precision medicine.


Assuntos
Neoplasias da Próstata , Receptores Androgênicos , Masculino , Humanos , Receptores Androgênicos/química , Ligação Proteica , Mutação , Neoplasias da Próstata/genética , Processamento de Proteína Pós-Traducional
17.
Int J Mol Sci ; 24(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36614192

RESUMO

KRAS is the most frequently mutated oncogene associated with the genesis and progress of pancreatic, lung and colorectal (CRC) tumors. KRAS has always been considered as a therapeutic target in cancer but until now only two compounds that inhibit one specific KRAS mutation have been approved for clinical use. In this work, by molecular dynamics and a docking process, we describe a new compound (P14B) that stably binds to a druggable pocket near the α4-α5 helices of the allosteric domain of KRAS. This region had previously been identified as the binding site for calmodulin (CaM). Using surface plasmon resonance and pulldown analyses, we prove that P14B binds directly to oncogenic KRAS thus competing with CaM. Interestingly, P14B favors oncogenic KRAS interaction with BRAF and phosphorylated C-RAF, and increases downstream Ras signaling in CRC cells expressing oncogenic KRAS. The viability of these cells, but not that of the normal cells, is impaired by P14B treatment. These data support the significance of the α4-α5 helices region of KRAS in the regulation of oncogenic KRAS signaling, and demonstrate that drugs interacting with this site may destine CRC cells to death by increasing oncogenic KRAS downstream signaling.


Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteínas Proto-Oncogênicas B-raf/genética , Transdução de Sinais/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Morte Celular , Mutação
18.
Retin Cases Brief Rep ; 17(6): 730-733, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35413723

RESUMO

PURPOSE: The purpose of this report was to describe a case of a dislocated Descemet stripping automated endothelial keratoplasty graft retained in-the-bag removed with pars plana vitrectomy (PPV). METHODS: This was a case report. RESULTS: A 69-year-old pseudophakic man who underwent a repeat Descemet stripping automated endothelial keratoplasty due to bullous keratopathy in the setting of multiple previous ocular surgeries presented with a vision of counting fingers. On examination, a Descemet stripping automated endothelial keratoplasty graft was appreciated behind the intraocular lens obscuring the visual axis and presumed to be in the anterior vitreous. The patient underwent a 23-gauge vitrectomy, and after a posterior capsulotomy, the dislocated graft was removed with a 23-gauge vitrector without complications. The best-corrected visual acuity was 20/50 6 months after the PPV. Grafts can dislocate posteriorly between the intraocular lens and the posterior capsule. The dislocated graft can be successfully extricated with a 23-gauge vitrector after a careful posterior capsulotomy, with good visual outcomes. IMPORTANCE: To the best of our knowledge, this is the first reported case of an in-the-bag Descemet stripping automated endothelial keratoplasty graft posterior dislocation. Furthermore, we showed an innovative surgical technique for the removal of the dislocated graft with a 23-gauge vitrectomy and posterior capsulotomy.


Assuntos
Doenças da Córnea , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Lentes Intraoculares , Masculino , Humanos , Idoso , Vitrectomia/métodos , Estudos Retrospectivos , Doenças da Córnea/cirurgia
19.
Cornea ; 42(7): 805-814, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36441843

RESUMO

PURPOSE: The purpose of this study was to assess the role of combined surgical treatment of therapeutic penetrating keratoplasty and pars plana vitrectomy in the anatomical and functional outcome of infectious keratitis endophthalmitis. METHODS: This study reviewed the medical records of 4 participating centers in the United States and Mexico. This study included patients with a clinical diagnosis of infectious keratitis endophthalmitis who had been treated with an early therapeutic penetrating keratoplasty and pars plana vitrectomy as the main treatment for endophthalmitis. From each medical record, the study retrieved demographic data, relevant medical and drug history, baseline clinical manifestation of endophthalmitis, best-corrected visual acuity, and the need for enucleation/evisceration for the control of the infection or any other reason through the follow-up. RESULTS: The study included 48 patients (50.15 ± 20.6 years). The mean follow-up time was 13 ± 0.5 months. The mean best-corrected visual acuity at baseline was 2.1 ± 0.25 logarithm of the minimum angle of resolution. At month 12 was 2.09 ± 0.61 logarithm of the minimum angle of resolution ( P = 0.9). The overall prevalence of enucleation/evisceration was 8.3% (95% confidence interval: 2.32%-19.98%). The prevalence of a vision of no-light perception was 20.8% (95% confidence interval: 2.32%-19.98%). CONCLUSIONS: Combined surgery for severe cases of infectious keratitis endophthalmitis eradicates the infection in most cases, while significantly improving the overall outcomes.


Assuntos
Endoftalmite , Ceratite , Humanos , Vitrectomia/métodos , Ceratoplastia Penetrante/métodos , México/epidemiologia , Resultado do Tratamento , Endoftalmite/diagnóstico , Endoftalmite/cirurgia , Endoftalmite/tratamento farmacológico , Ceratite/cirurgia , Estudos Retrospectivos
20.
Health Expect ; 26(1): 429-439, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36416386

RESUMO

INTRODUCTION: The informed consent process is key to safeguarding the autonomy of the participant in medical research. For this process to be valid, the information presented to the potential participant should meet their needs and be understood by them. The i-CONSENT project has developed 'Guidelines for adapting the informed consent process in clinical trials' which aim to improve informed consent so that they are easier to understand and better adapted to the needs and preferences of the target population. The best way to tailor information to the characteristics and preferences of the target population is to involve the community itself. METHODS: Following guidelines developed by i-CONSENT, assent materials were co-created for a mock clinical trial of the human papillomavirus vaccine in adolescents. During the process, two design thinking sessions were conducted involving a total of 10 children and 5 parents. The objectives of the sessions were to find out the children's opinion of the informed consent (assent in their case) process in clinical trials, identify the parts that were most difficult to understand and alternatives for their presentation and wording, identify the preferred formats for receiving the information and the main characteristics of these formats, design a video explaining the clinical trial and evaluate a tool for assessing comprehension. RESULTS: Assent materials were co-created in three formats: a web-based material following a layered approach; a video in story format; a pdf document with an innovative way of presenting information compared to traditional assent documents. In addition, the Comprehension of Assent Questionnaire was co-designed, based on the Quality of Informed Consent questionnaire. CONCLUSION: The design thinking methodology has proven to be an easy and useful tool for involving children in designing information tailored to their needs and preferences. PATIENT OR PUBLIC CONTRIBUTION: A sample of the target population participated in the design and piloting of the materials created using design thinking methodology. In addition, patient representatives participated in the design and evaluation of the guidelines developed by the i-CONSENT project that were followed for the development of the materials in this study.


Assuntos
Pesquisa Biomédica , Consentimento Livre e Esclarecido , Criança , Adolescente , Humanos , Pais , Projetos de Pesquisa , Inquéritos e Questionários
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