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1.
N Engl J Med ; 390(11): 994-1008, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38477987

RESUMO

BACKGROUND: Persistent hemolytic anemia and a lack of oral treatments are challenges for patients with paroxysmal nocturnal hemoglobinuria who have received anti-C5 therapy or have not received complement inhibitors. Iptacopan, a first-in-class oral factor B inhibitor, has been shown to improve hemoglobin levels in these patients. METHODS: In two phase 3 trials, we assessed iptacopan monotherapy over a 24-week period in patients with hemoglobin levels of less than 10 g per deciliter. In the first, anti-C5-treated patients were randomly assigned to switch to iptacopan or to continue anti-C5 therapy. In the second, single-group trial, patients who had not received complement inhibitors and who had lactate dehydrogenase (LDH) levels more than 1.5 times the upper limit of the normal range received iptacopan. The two primary end points in the first trial were an increase in the hemoglobin level of at least 2 g per deciliter from baseline and a hemoglobin level of at least 12 g per deciliter, each without red-cell transfusion; the primary end point for the second trial was an increase in hemoglobin level of at least 2 g per deciliter from baseline without red-cell transfusion. RESULTS: In the first trial, 51 of the 60 patients who received iptacopan had an increase in the hemoglobin level of at least 2 g per deciliter from baseline, and 42 had a hemoglobin level of at least 12 g per deciliter, each without transfusion; none of the 35 anti-C5-treated patients attained the end-point levels. In the second trial, 31 of 33 patients had an increase in the hemoglobin level of at least 2 g per deciliter from baseline without red-cell transfusion. In the first trial, 59 of the 62 patients who received iptacopan and 14 of the 35 anti-C5-treated patients did not require or receive transfusion; in the second trial, no patients required or received transfusion. Treatment with iptacopan increased hemoglobin levels, reduced fatigue, reduced reticulocyte and bilirubin levels, and resulted in mean LDH levels that were less than 1.5 times the upper limit of the normal range. Headache was the most frequent adverse event with iptacopan. CONCLUSIONS: Iptacopan treatment improved hematologic and clinical outcomes in anti-C5-treated patients with persistent anemia - in whom iptacopan showed superiority to anti-C5 therapy - and in patients who had not received complement inhibitors. (Funded by Novartis; APPLY-PNH ClinicalTrials.gov number, NCT04558918; APPOINT-PNH ClinicalTrials.gov number, NCT04820530.).


Assuntos
Anemia Hemolítica , Fator B do Complemento , Inativadores do Complemento , Hemoglobinas , Hemoglobinúria Paroxística , Humanos , Administração Oral , Anemia Hemolítica/complicações , Complemento C5/antagonistas & inibidores , Fator B do Complemento/antagonistas & inibidores , Inativadores do Complemento/administração & dosagem , Inativadores do Complemento/efeitos adversos , Inativadores do Complemento/uso terapêutico , Transfusão de Eritrócitos , Cefaleia/induzido quimicamente , Hemoglobinas/análise , Hemoglobinúria Paroxística/tratamento farmacológico , Hemoglobinúria Paroxística/etiologia , Ensaios Clínicos Fase III como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
BMC Biol ; 22(1): 14, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273313

RESUMO

BACKGROUND: Mosquito borne viruses, such as dengue, Zika, yellow fever and Chikungunya, cause millions of infections every year. These viruses are mostly transmitted by two urban-adapted mosquito species, Aedes aegypti and Aedes albopictus. Although mechanistic understanding remains largely unknown, Aedes mosquitoes may have unique adaptations that lower the impact of viral infection. Recently, we reported the identification of an Aedes specific double-stranded RNA binding protein (dsRBP), named Loqs2, that is involved in the control of infection by dengue and Zika viruses in mosquitoes. Preliminary analyses suggested that the loqs2 gene is a paralog of loquacious (loqs) and r2d2, two co-factors of the RNA interference (RNAi) pathway, a major antiviral mechanism in insects. RESULTS: Here we analyzed the origin and evolution of loqs2. Our data suggest that loqs2 originated from two independent duplications of the first double-stranded RNA binding domain of loqs that occurred before the origin of the Aedes Stegomyia subgenus, around 31 million years ago. We show that the loqs2 gene is evolving under relaxed purifying selection at a faster pace than loqs, with evidence of neofunctionalization driven by positive selection. Accordingly, we observed that Loqs2 is localized mainly in the nucleus, different from R2D2 and both isoforms of Loqs that are cytoplasmic. In contrast to r2d2 and loqs, loqs2 expression is stage- and tissue-specific, restricted mostly to reproductive tissues in adult Ae. aegypti and Ae. albopictus. Transgenic mosquitoes engineered to express loqs2 ubiquitously undergo developmental arrest at larval stages that correlates with massive dysregulation of gene expression without major effects on microRNAs or other endogenous small RNAs, classically associated with RNA interference. CONCLUSIONS: Our results uncover the peculiar origin and neofunctionalization of loqs2 driven by positive selection. This study shows an example of unique adaptations in Aedes mosquitoes that could ultimately help explain their effectiveness as virus vectors.


Assuntos
Aedes , Dengue , Infecção por Zika virus , Zika virus , Animais , Aedes/genética , Proteínas de Transporte/genética , Mosquitos Vetores/genética , RNA de Cadeia Dupla/genética , RNA de Cadeia Dupla/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Zika virus/genética , Zika virus/metabolismo
3.
Nano Lett ; 24(10): 3097-3103, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38417053

RESUMO

To date, studies on the thermodynamic and kinetic processes that underlie biological function and nanomachine actuation in biological- and biology-inspired molecular constructs have primarily focused on photothermal heating of ensemble systems, highlighting the need for probes that are localized within the molecular construct and capable of resolving single-molecule response. Here we present an experimental demonstration of wavelength-selective, localized heating at the single-molecule level using the surface plasmon resonance of a 15 nm gold nanoparticle (AuNP). Our approach is compatible with force-spectroscopy measurements and can be applied to studies of the single-molecule thermodynamic properties of DNA origami nanomachines as well as biomolecular complexes. We further demonstrate wavelength selectivity and establish the temperature dependence of the reaction coordinate for base-pair disruption in the shear-rupture geometry, demonstrating the utility and flexibility of this approach for both fundamental studies of local (nanometer-scale) temperature gradients and rapid and multiplexed nanomachine actuation.


Assuntos
Ouro , Nanopartículas Metálicas , Ouro/química , Pinças Ópticas , Calefação , Nanopartículas Metálicas/química , DNA/química
4.
BMC Bioinformatics ; 25(1): 189, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745271

RESUMO

BACKGROUND: The selection of primer pairs in sequencing-based research can greatly influence the results, highlighting the need for a tool capable of analysing their performance in-silico prior to the sequencing process. We therefore propose PrimerEvalPy, a Python-based package designed to test the performance of any primer or primer pair against any sequencing database. The package calculates a coverage metric and returns the amplicon sequences found, along with information such as their average start and end positions. It also allows the analysis of coverage for different taxonomic levels. RESULTS: As a case study, PrimerEvalPy was used to test the most commonly used primers in the literature against two oral 16S rRNA gene databases containing bacteria and archaea. The results showed that the most commonly used primer pairs in the oral cavity did not match those with the highest coverage. The best performing primer pairs were found for the detection of oral bacteria and archaea. CONCLUSIONS: This demonstrates the importance of a coverage analysis tool such as PrimerEvalPy to find the best primer pairs for specific niches. The software is available under the MIT licence at https://gitlab.citius.usc.es/lara.vazquez/PrimerEvalPy .


Assuntos
Archaea , Bactérias , Primers do DNA , Microbiota , RNA Ribossômico 16S , Software , Microbiota/genética , RNA Ribossômico 16S/genética , Bactérias/genética , Bactérias/classificação , Archaea/genética , Primers do DNA/metabolismo , Primers do DNA/genética , Humanos , Boca/microbiologia , Simulação por Computador
5.
N Engl J Med ; 384(11): 1028-1037, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33730455

RESUMO

BACKGROUND: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired disease characterized by chronic complement-mediated hemolysis. C5 inhibition controls intravascular hemolysis in untreated PNH but cannot address extravascular hemolysis. Pegcetacoplan, a pegylated peptide targeting proximal complement protein C3, potentially inhibits both intravascular and extravascular hemolysis. METHODS: We conducted a phase 3 open-label, controlled trial to assess the efficacy and safety of pegcetacoplan as compared with eculizumab in adults with PNH and hemoglobin levels lower than 10.5 g per deciliter despite eculizumab therapy. After a 4-week run-in phase in which all patients received pegcetacoplan plus eculizumab, we randomly assigned patients to subcutaneous pegcetacoplan monotherapy (41 patients) or intravenous eculizumab (39 patients). The primary end point was the mean change in hemoglobin level from baseline to week 16. Additional clinical and hematologic markers of hemolysis and safety were assessed. RESULTS: Pegcetacoplan was superior to eculizumab with respect to the change in hemoglobin level from baseline to week 16, with an adjusted (least squares) mean difference of 3.84 g per deciliter (P<0.001). A total of 35 patients (85%) receiving pegcetacoplan as compared with 6 patients (15%) receiving eculizumab no longer required transfusions. Noninferiority of pegcetacoplan to eculizumab was shown for the change in absolute reticulocyte count but not for the change in lactate dehydrogenase level. Functional Assessment of Chronic Illness Therapy-Fatigue scores improved from baseline in the pegcetacoplan group. The most common adverse events that occurred during treatment in the pegcetacoplan and eculizumab groups were injection site reactions (37% vs. 3%), diarrhea (22% vs. 3%), breakthrough hemolysis (10% vs. 23%), headache (7% vs. 23%), and fatigue (5% vs. 15%). There were no cases of meningitis in either group. CONCLUSIONS: Pegcetacoplan was superior to eculizumab in improving hemoglobin and clinical and hematologic outcomes in patients with PNH by providing broad hemolysis control, including control of intravascular and extravascular hemolysis. (Funded by Apellis Pharmaceuticals; PEGASUS ClinicalTrials.gov, NCT03500549.).


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Complemento C3/antagonistas & inibidores , Complemento C5/antagonistas & inibidores , Inativadores do Complemento/uso terapêutico , Hemoglobinúria Paroxística/tratamento farmacológico , Peptídeos/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/efeitos adversos , Inativadores do Complemento/efeitos adversos , Diarreia/induzido quimicamente , Quimioterapia Combinada , Transfusão de Eritrócitos , Hemoglobinas/análise , Hemoglobinúria Paroxística/sangue , Hemoglobinúria Paroxística/terapia , Humanos , Injeções Subcutâneas/efeitos adversos , Pessoa de Meia-Idade , Peptídeos/efeitos adversos , Peptídeos Cíclicos
6.
J Biol Inorg Chem ; 29(4): 407-425, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38811408

RESUMO

The influence of metal ions on the structure of amyloid- ß (Aß) protofibril models was studied through molecular dynamics to explore the molecular mechanisms underlying metal-induced Aß aggregation relevant in Alzheimer's disease (AD). The models included 36-, 48-, and 188-mers of the Aß42 sequence and two disease-modifying variants. Primary structural effects were observed at the N-terminal domain, as it became susceptible to the presence of cations. Specially when ß-sheets predominate, this motif orients N-terminal acidic residues toward one single face of the ß-sheet, resulting in the formation of an acidic region that attracts cations from the media and promotes the folding of the N-terminal region, with implications in amyloid aggregation. The molecular phenotype of the protofibril models based on Aß variants shows that the AD-causative D7N mutation promotes the formation of N-terminal ß-sheets and accumulates more Zn2+, in contrast to the non-amyloidogenic rodent sequence that hinders the ß-sheets and is more selective for Na+ over Zn2+ cations. It is proposed that forming an acidic ß-sheet domain and accumulating cations is a plausible molecular mechanism connecting the elevated affinity and concentration of metals in Aß fibrils to their high content of ß-sheet structure at the N-terminal sequence.


Assuntos
Peptídeos beta-Amiloides , Simulação de Dinâmica Molecular , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/genética , Conformação Proteica em Folha beta , Humanos , Zinco/metabolismo , Zinco/química , Doença de Alzheimer/metabolismo , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/genética , Metais/metabolismo , Metais/química
7.
PLoS Comput Biol ; 19(11): e1011673, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37992135

RESUMO

We analyzed a quantitative multiscale model that describes the epigenetic dynamics during the growth and evolution of an avascular tumor. A gene regulatory network (GRN) formed by a set of ten genes that are believed to play an important role in breast cancer development was kinetically coupled to the microenvironmental agents: glucose, estrogens, and oxygen. The dynamics of spontaneous mutations was described by a Yule-Furry master equation whose solution represents the probability that a given cell in the tissue undergoes a certain number of mutations at a given time. We assumed that the mutation rate is modified by a spatial gradient of nutrients. The tumor mass was simulated by means of cellular automata supplemented with a set of reaction diffusion equations that described the transport of microenvironmental agents. By analyzing the epigenetic state space described by the GRN dynamics, we found three attractors that were identified with cellular epigenetic states: normal, precancer and cancer. For two-dimensional (2D) and three-dimensional (3D) tumors we calculated the spatial distribution of the following quantities: (i) number of mutations, (ii) mutation of each gene and, (iii) phenotypes. Using estrogen as the principal microenvironmental agent that regulates cell proliferation process, we obtained tumor shapes for different values of estrogen consumption and supply rates. It was found that he majority of mutations occurred in cells that were located close to the 2D tumor perimeter or close to the 3D tumor surface. Also, it was found that the occurrence of different phenotypes in the tumor are controlled by estrogen concentration levels since they can change the individual cell threshold and gene expression levels. All results were consistently observed for 2D and 3D tumors.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proliferação de Células/genética , Difusão , Separação Celular , Estrogênios
8.
Artigo em Inglês | MEDLINE | ID: mdl-38498600

RESUMO

Angiotensin (Ang)-(1-7) is a cardioprotective peptide of the renin-angiotensin system. Pre-puberty has been considered as a later susceptible window of development and stressful factors in this life phase can induce chronic diseases in adulthood. We aimed to investigate whether the treatment with Ang-(1-7) during the pre-puberty could attenuate the development of hypertension and cardiac injury in adult spontaneously hypertensive rats (SHR). SHR were treated with Ang-(1-7) (24 µg/Kg/h) from 4 to 7 weeks of age. Systolic blood pressure (SBP) was measured by tail-cuff plethysmography up to 17th of age. Thereafter, echocardiography was performed and the rats were euthanized for aorta reactivity assay and tissues and blood collections. Ang- (1-7) did not change the SBP and aortic reactivity but reduced the septal and posterior wall thickness, cardiomyocyte hypertrophy and fibrosis in SHR. Additionally, Ang-(1-7) reduced the gene expression of ANP and BNP, increased the metalloproteinase 9 expression, and reduced the ERK 1/2 phosphorylation. Ang-(1-7) also prevented the reduction of Mas receptor but did not change the protein expression of ACE2, ACE, AT1, and AT2. The treatment with Ang-(1-7) decreased the MDA levels and increased SOD-1 and catalase activity and protein expression of catalase. Our findings demonstrate that the treatment of SHR with Ang-(1-7) for three weeks early in life promotes beneficial effects in the heart later in life, even without altering blood pressure, through mechanisms involving the reduction of oxidative stress and ERK1/2 phosphorylation. Additionally, this study supports the pre-puberty as an important programming window.

9.
Exp Parasitol ; 256: 108670, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38092297

RESUMO

Ivermectin (IVM) resistance in parasitic nematodes such as Haemonchus contortus has spurred a search for substances that help to recover its efficacy. One potential agent is the natural product curcumin (CUR). In this study, CUR was combined with polyvinylpyrrolidone (PVP) (CUR/PVP) to improve its solubility and biological applicability. This study determined the effect of CUR preincubation on the effective concentration 50% (EC50) of IVM in three H. contortus isolates with different susceptibilities to IVM. The IVM EC50 was determined for three H. contortus isolates with different IVM susceptibilities using the larval migration inhibition (LMI) test. The three isolates were (i) PARAISO (IVM resistant), (ii) FMVZ-UADY (IVM susceptible), and (iii) CENID-SAI INIFAP (reference IVM susceptible). The L3 of each isolate were preincubated for 3 h with one of three concentrations of CUR (µg curcumin/mL): CONC-1 (3.67), CONC-2 (5.67), or CONC-3 (8.48). Corresponding controls were performed without CUR. The EC50 of IVM was determined for each isolate after they were exposed to the different CUR concentrations. The EC50 of IVM differed between the isolates PARAISO > FMVZ-UADY > CENID-SAI INIFAP (P < 0.05). The CUR preincubation at CONC-1 did not decrease the EC50 of IVM for any of the three isolates, suggesting a hormetic effect. By contrast, CUR preincubation at CONC-2 or CONC-3 decreased the IVM EC50 for the PARAISO isolate (P < 0.05) compared with the reference isolate and reduced the EC50 of IVM for the FMVZ-UADY and CENID-SAI INIFAP isolates below the EC50 for the CENID-SAI INIFAP isolate without CUR preincubation. In conclusion, preincubation of H. contortus L3 with CUR reduced the EC50 of IVM for field isolates classified as resistant and susceptible to IVM. The CUR preincubation reduced the IVM resistance factor in the different isolates tested.


Assuntos
Anti-Helmínticos , Curcumina , Hemoncose , Haemonchus , Animais , Ivermectina/farmacologia , Ivermectina/uso terapêutico , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Curcumina/farmacologia , Curcumina/uso terapêutico , Povidona/farmacologia , Povidona/uso terapêutico , Resistência a Medicamentos , Larva , Hemoncose/tratamento farmacológico , Hemoncose/veterinária
10.
Nucleic Acids Res ; 50(3): 1256-1268, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35104875

RESUMO

DNA nanostructures are a promising tool to deliver molecular payloads to cells. DNA origami structures, where long single-stranded DNA is folded into a compact nanostructure, present an attractive approach to package genes; however, effective delivery of genetic material into cell nuclei has remained a critical challenge. Here, we describe the use of DNA nanostructures encoding an intact human gene and a fluorescent protein encoding gene as compact templates for gene integration by CRISPR-mediated homology-directed repair (HDR). Our design includes CRISPR-Cas9 ribonucleoprotein binding sites on DNA nanostructures to increase shuttling into the nucleus. We demonstrate efficient shuttling and genomic integration of DNA nanostructures using transfection and electroporation. These nanostructured templates display lower toxicity and higher insertion efficiency compared to unstructured double-stranded DNA templates in human primary cells. Furthermore, our study validates virus-like particles as an efficient method of DNA nanostructure delivery, opening the possibility of delivering nanostructures in vivo to specific cell types. Together, these results provide new approaches to gene delivery with DNA nanostructures and establish their use as HDR templates, exploiting both their design features and their ability to encode genetic information. This work also opens a door to translate other DNA nanodevice functions, such as biosensing, into cell nuclei.


Assuntos
Técnicas de Transferência de Genes , Nanoestruturas , Transporte Ativo do Núcleo Celular , Sistemas CRISPR-Cas , DNA/genética , Edição de Genes/métodos , Genoma , Humanos
11.
Ann Surg ; 278(5): e949-e956, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37476995

RESUMO

OBJECTIVE: To determine how the severity of prior history (Hx) of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection influences postoperative outcomes after major elective inpatient surgery. BACKGROUND: Surgical guidelines instituted early in the coronavirus disease 2019 (COVID-19) pandemic recommended a delay in surgery of up to 8 weeks after an acute SARS-CoV-2 infection. This was based on the observation of elevated surgical risk after recovery from COVID-19 early in the pandemic. As the pandemic shifts to an endemic phase, it is unclear whether this association remains, especially for those recovering from asymptomatic or mildly symptomatic COVID-19. METHODS: Utilizing the National COVID Cohort Collaborative, we assessed postoperative outcomes for adults with and without a Hx of COVID-19 who underwent major elective inpatient surgery between January 2020 and February 2023. COVID-19 severity and time from infection to surgery were each used as independent variables in multivariable logistic regression models. RESULTS: This study included 387,030 patients, of whom 37,354 (9.7%) were diagnosed with preoperative COVID-19. Hx of COVID-19 was found to be an independent risk factor for adverse postoperative outcomes even after a 12-week delay for patients with moderate and severe SARS-CoV-2 infection. Patients with mild COVID-19 did not have an increased risk of adverse postoperative outcomes at any time point. Vaccination decreased the odds of respiratory failure. CONCLUSIONS: Impact of COVID-19 on postoperative outcomes is dependent on the severity of illness, with only moderate and severe disease leading to a higher risk of adverse outcomes. Existing perioperative policies should be updated to include consideration of COVID-19 disease severity and vaccination status.


Assuntos
COVID-19 , Adulto , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , Pacientes Internados , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Fatores de Risco
12.
Am J Physiol Heart Circ Physiol ; 324(6): H721-H731, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36930659

RESUMO

As the coronavirus disease 2019 (COVID-19) pandemic progresses to an endemic phase, a greater number of patients with a history of COVID-19 will undergo surgery. Major adverse cardiovascular and cerebrovascular events (MACE) are the primary contributors to postoperative morbidity and mortality; however, studies assessing the relationship between a previous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and postoperative MACE outcomes are limited. Here, we analyzed retrospective data from 457,804 patients within the N3C Data Enclave, the largest national, multi-institutional data set on COVID-19 in the United States. However, 7.4% of patients had a history of COVID-19 before surgery. When comorbidities, age, race, and risk of surgery were controlled, patients with preoperative COVID-19 had an increased risk for 30-day postoperative MACE. MACE risk was influenced by an interplay between COVID-19 disease severity and time between surgery and infection; in those with mild disease, MACE risk was not increased even among those undergoing surgery within 4 wk following infection. In those with moderate disease, risk for postoperative MACE was mitigated 8 wk after infection, whereas patients with severe disease continued to have elevated postoperative MACE risk even after waiting for 8 wk. Being fully vaccinated decreased the risk for postoperative MACE in both patients with no history of COVID-19 and in those with breakthrough COVID-19 infection. Together, our results suggest that a thorough assessment of the severity, vaccination status, and timing of SARS-CoV-2 infection must be a mandatory part of perioperative stratification.NEW & NOTEWORTHY With an increasing proportion of patients undergoing surgery with a prior history of COVID-19, it is crucial to understand the impact of SARS-CoV-2 infection on postoperative cardiovascular/cerebrovascular risk. Our work assesses a large, national, multi-institutional cohort of patients to highlight that COVID-19 infection increases risk for postoperative major adverse cardiovascular and cerebrovascular events (MACE). MACE risk is influenced by an interplay between disease severity and time between infection and surgery, and full vaccination reduces the risk for 30-day postoperative MACE. These results highlight the importance of stratifying time-to-surgery guidelines based on disease severity.


Assuntos
COVID-19 , Humanos , Estados Unidos , COVID-19/complicações , COVID-19/diagnóstico , Estudos Retrospectivos , SARS-CoV-2 , Infecções Irruptivas , Complicações Pós-Operatórias/epidemiologia
13.
J Chem Inf Model ; 63(4): 1157-1165, 2023 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-36749172

RESUMO

We present an improved algorithm to solve the near-congruence problem for rigid molecules and clusters based on the iterative application of assignment and alignment steps with biased Euclidean costs. The algorithm is formulated as a quasi-local optimization procedure with each optimization step involving a linear assignment (LAP) and a singular value decomposition (SVD). The efficiency of the algorithm is increased by up to 5 orders of magnitude with respect to the original unbiased noniterative method and can be applied to systems with hundreds or thousands of atoms, outperforming all state-of-the-art methods published so far in the literature. The Fortran implementation of the algorithm is available as an open source library (https://github.com/qcuaeh/molalignlib) and is suitable to be used in global optimization methods for the identification of local minima or basins.

14.
Environ Sci Technol ; 57(50): 21136-21144, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38051294

RESUMO

Marine dissolved organic matter (DOM) presents key thermodynamic properties that are not yet fully constrained. Here, we report the distribution of binding sites occupied by protons (i.e., proton affinity spectra) and parametrize the median intrinsic proton binding affinities (log K̅H) and heterogeneities (m), for DOM samples extracted from the North Atlantic. We estimate that 11.4 ± 0.6% of C atoms in the extracted marine DOM have a functional group with a binding site for ionic species. The log K̅H of the most acidic groups was larger (4.01-4.02 ± 0.02) than that observed in DOM from coastal waters (3.82 ± 0.02), while the chemical binding heterogeneity parameter increased with depth to values (m1= 0.666 ± 0.009) ca. 10% higher than those observed in surface open ocean or coastal samples. On the contrary, the log K̅H for the less acidic groups shows a difference between the surface (10.01 ± 0.08) and deep (9.22 ± 0.35) samples. The latter chemical groups were more heterogeneous for marine than for terrestrial DOM, and m2 decreased with depth to values of 0.28 ± 0.03. Binding heterogeneity reflects aromatic carbon compounds' persistence and accumulation in diverse, low-abundance chemical forms, while easily degradable low-affinity groups accumulate more uniformly in the deep ocean.


Assuntos
Matéria Orgânica Dissolvida , Prótons , Compostos Orgânicos , Íons
15.
Biotechnol Appl Biochem ; 70(3): 1015-1023, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36441921

RESUMO

Lectins are carbohydrate-binding proteins belonging to the Leguminosae family. In this family stand out proteins extracted from species belonging to Diocleinae subtribe, which includes, for example, the seed lectin from Dioclea violacea (DVL) and the jack bean lectin Concanavalin A (ConA). Here, we report the photosynthesis of silver/silver chloride nanoparticles (NPs) assisted by ConA and DVL. The syntheses were simple processes using a green-chemistry approach. Under electron microscopy, NPs heterogeneous in size, nearly spherical and covered by a thin lectin corona, were observed. Both NPs assisted by lectins were capable to cause strong rabbit erythrocytes agglutination with the same titers of hemagglutinating activities. These results indicate that both lectins maintained their biological activities even after association with the NPs and therefore are able to interact with biological membrane carbohydrates. However, for rabbit erythrocytes treated with proteolytic enzymes were observed different titers of hemagglutinating activities, suggesting differences in the spatial arrangement of the lectins on the surface of the NPs. This study provides evidences that these hybrid lectin-coated silver/silver chloride NPs can be used for selective recognition and interaction with membrane carbohydrates and others biotechnological applications.


Assuntos
Lectinas , Lectinas de Plantas , Animais , Coelhos , Lectinas/química , Lectinas de Plantas/farmacologia , Lectinas de Plantas/química , Lectinas de Plantas/metabolismo , Prata/farmacologia , Carboidratos/química , Fotossíntese
16.
Nucleic Acids Res ; 49(15): 8987-8999, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34358322

RESUMO

Single molecule force spectroscopy is a powerful approach to probe the structure, conformational changes, and kinetic properties of biological and synthetic macromolecules. However, common approaches to apply forces to biomolecules require expensive and cumbersome equipment and relatively large probes such as beads or cantilevers, which limits their use for many environments and makes integrating with other methods challenging. Furthermore, existing methods have key limitations such as an inability to apply compressive forces on single molecules. We report a nanoscale DNA force spectrometer (nDFS), which is based on a DNA origami hinge with tunable mechanical and dynamic properties. The angular free energy landscape of the nDFS can be engineered across a wide range through substitution of less than 5% of the strand components. We further incorporate a removable strut that enables reversible toggling of the nDFS between open and closed states to allow for actuated application of tensile and compressive forces. We demonstrate the ability to apply compressive forces by inducing a large bend in a 249bp DNA molecule, and tensile forces by inducing DNA unwrapping of a nucleosome sample. These results establish a versatile tool for force spectroscopy and robust methods for designing nanoscale mechanical devices with tunable force application.


Assuntos
DNA/química , Nanoestruturas/química , Bioengenharia , Fenômenos Biomecânicos , Nucleossomos/química , Análise Espectral
17.
Parasitol Res ; 122(3): 833-845, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36670313

RESUMO

This study developed and evaluated an in vitro rumen incubation (IVRI) method to describe the exsheathment kinetics of Haemonchus contortus third-stage infective larvae (L3) in ruminal liquor (RL). The specific objectives were (i) to standardize the IVRI method to facilitate the contact between L3 and RL as well as the larval recovery, and (ii) to apply the IVRI method to describe the exsheathment kinetics of H. contortus and to select the best fitting nonlinear model. Incubation devices containing H. contortus larvae were incubated according to the IVRI technique in cattle RL or PBS. The incubation conditions included RL mixed with a nitrogen-rich media, maintained at 39 °C, with pH = 7.0, vented with CO2 and manual agitation. The larvae were recovered after 0, 1, 3, 6, 9, 12, and 24 h. The exsheathed and ensheathed larvae were counted to estimate the exsheathment (%) in RL or PBS. Exsheathment in RL was analyzed with nonlinear regression models: Exponential, Gompertz, Logistic, Log-Logistic, and Weibull. The models' fit was compared to select the one that best described the exsheathment kinetics. The exsheathment in RL reached 6.52%, 20.65%, 58.22%, 69.24%, 73.08%, and 77.20% in 1, 3, 6, 9, 12, and 24 h, respectively. Although the Gompertz, Weibull, and Logistic models were adequate to describe the observed exsheathment, the Log-Logistic model had the best fit. The IVRI method using bovine RL represents a suitable tool for the study of the in vitro exsheathment kinetics of H. contortus L3.


Assuntos
Haemonchus , Animais , Bovinos , Larva , Cinética , Rúmen , Técnicas In Vitro
18.
Clin Oral Investig ; 27(9): 4929-4955, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37535199

RESUMO

AIM: To explore the existing salivary, gingival crevicular fluid (GCF), blood, and serum biomarkers associated with grade C molar-incisor pattern (C/MIP) periodontitis in systemically healthy children and young adults. MATERIALS AND METHODS: Cross-sectional, case-control, and cohort studies on stage III grade C periodontitis or former equivalent diagnosis with analysis of molecular biomarkers in saliva, GCF, blood, or serum were retrieved from six databases and screened based on the eligibility criteria. The risk of bias in included studies was evaluated. Meta-analysis was planned for biomarkers assessed using the same detection methods and sample type in at least two papers. RESULTS: Out of 5621 studies identified at initial screening, 28 papers were included in the qualitative analysis of which 2 were eligible for meta-analysis for IgG in serum samples. Eighty-seven biomarkers were assessed with the majority being higher in cases than in controls. Only the meta-analysis of total serum IgG with low heterogeneity value revealed a significant increase in its levels in C/MIPs compared to controls (standardised mean difference: 1.08; 95% CI: 0.76, 1.40). CONCLUSION: There is a paucity of data on biomarkers associated with molar-incisor pattern periodontitis. Although serum IgG levels are raised, other more specific biomarkers in saliva, GCF, and blood/serum may be promising but require further investigation.


Assuntos
Hipoplasia do Esmalte Dentário , Periodontite , Humanos , Criança , Adulto Jovem , Estudos Transversais , Incisivo , Periodontite/diagnóstico , Biomarcadores/análise , Imunoglobulina G , Líquido do Sulco Gengival/química , Saliva/química
19.
J Food Sci Technol ; 60(9): 2297-2308, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37424571

RESUMO

The development of yogurt with functional characteristics from bioactive compounds such as fiber, antioxidants, and probiotics represents a novel strategy in designing value-added dairy beverages. However, biotechnological challenges are present in these bioprocesses, such as the selection of probiotic strains, as well as the correlation with the physicochemical characteristics of the fermentative metabolism of probiotic microorganisms. Therefore, yogurt could be a vehicle for including probiotic bacteria, bioactive compounds, and phytochemicals that allow synergistic effects in the development of bioprocesses with potential benefits for the host's health. Therefore, this article aims to review the current conditions of bio-yogurt production, discuss the physicochemical and bioactive composition (sugars, fiber, vitamins), and include phytochemicals from carrots to establish synergistic relationships with probiotic microorganisms to obtain a functional dairy beverage.

20.
Small ; 18(26): e2108063, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35633287

RESUMO

DNA origami (DO) nanotechnology enables the construction of precise nanostructures capable of functionalization with small molecule drugs, nucleic acids, and proteins, suggesting a promising platform for biomedical applications. Despite the potential for drug and vaccine delivery, the impact of DO vehicles on immunogenicity in vivo is not well understood. Here, two DO vehicles, a flat triangle and a nanorod, at varying concentrations are evaluated in vitro and with a repeated dosing regimen administered at a high dose in vivo to study early and late immunogenicity. The studies show normal CD11b+ myeloid cell populations preferentially internalize DO in vitro. DO structures distribute well systemically in vivo, elicit a modest pro-inflammatory immune response that diminishes over time and are nontoxic as shown by weight, histopathology, lack of cytokine storm, and a complete biochemistry panel at the day 10 end point. The results take critical steps to characterize the biological response to DO and suggest that DO vehicles represent a promising platform for drug delivery and vaccine development where immunogenicity should be a key consideration.


Assuntos
Nanoestruturas , DNA/química , Sistemas de Liberação de Medicamentos/métodos , Nanoestruturas/química , Nanotecnologia/métodos , Conformação de Ácido Nucleico , Preparações Farmacêuticas , Proteínas
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