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1.
Cell ; 185(9): 1556-1571.e18, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35447072

RESUMO

SARS-CoV-2 Omicron is highly transmissible and has substantial resistance to neutralization following immunization with ancestral spike-matched vaccines. It is unclear whether boosting with Omicron-matched vaccines would enhance protection. Here, nonhuman primates that received mRNA-1273 at weeks 0 and 4 were boosted at week 41 with mRNA-1273 or mRNA-Omicron. Neutralizing titers against D614G were 4,760 and 270 reciprocal ID50 at week 6 (peak) and week 41 (preboost), respectively, and 320 and 110 for Omicron. 2 weeks after the boost, titers against D614G and Omicron increased to 5,360 and 2,980 for mRNA-1273 boost and 2,670 and 1,930 for mRNA-Omicron, respectively. Similar increases against BA.2 were observed. Following either boost, 70%-80% of spike-specific B cells were cross-reactive against WA1 and Omicron. Equivalent control of virus replication in lower airways was observed following Omicron challenge 1 month after either boost. These data show that mRNA-1273 and mRNA-Omicron elicit comparable immunity and protection shortly after the boost.


Assuntos
COVID-19 , SARS-CoV-2 , Vacina de mRNA-1273 contra 2019-nCoV , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Macaca , RNA Mensageiro
2.
Nat Immunol ; 25(10): 1913-1927, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39227514

RESUMO

A mucosal route of vaccination could prevent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) replication at the site of infection and limit transmission. We compared protection against heterologous XBB.1.16 challenge in nonhuman primates (NHPs) ~5 months following intramuscular boosting with bivalent mRNA encoding WA1 and BA.5 spike proteins or mucosal boosting with a WA1-BA.5 bivalent chimpanzee adenoviral-vectored vaccine delivered by intranasal or aerosol device. NHPs boosted by either mucosal route had minimal virus replication in the nose and lungs, respectively. By contrast, protection by intramuscular mRNA was limited to the lower airways. The mucosally delivered vaccine elicited durable airway IgG and IgA responses and, unlike the intramuscular mRNA vaccine, induced spike-specific B cells in the lungs. IgG, IgA and T cell responses correlated with protection in the lungs, whereas mucosal IgA alone correlated with upper airway protection. This study highlights differential mucosal and serum correlates of protection and how mucosal vaccines can durably prevent infection against SARS-CoV-2.


Assuntos
Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Imunização Secundária , Imunoglobulina A , SARS-CoV-2 , Animais , Imunoglobulina A/imunologia , SARS-CoV-2/imunologia , COVID-19/prevenção & controle , COVID-19/imunologia , COVID-19/virologia , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Macaca mulatta , Adenoviridae/imunologia , Adenoviridae/genética , Imunidade nas Mucosas , Vacinas contra Adenovirus/imunologia , Vacinas contra Adenovirus/administração & dosagem , Feminino , Pulmão/virologia , Pulmão/imunologia , Linfócitos B/imunologia , Imunoglobulina G/imunologia , Imunoglobulina G/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/sangue , Administração Intranasal , Vacinação/métodos , Humanos
3.
Nat Immunol ; 22(10): 1306-1315, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34417590

RESUMO

B.1.351 is the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant most resistant to antibody neutralization. We demonstrate how the dose and number of immunizations influence protection. Nonhuman primates received two doses of 30 or 100 µg of Moderna's mRNA-1273 vaccine, a single immunization of 30 µg, or no vaccine. Two doses of 100 µg of mRNA-1273 induced 50% inhibitory reciprocal serum dilution neutralizing antibody titers against live SARS-CoV-2 p.Asp614Gly and B.1.351 of 3,300 and 240, respectively. Higher neutralizing responses against B.1.617.2 were also observed after two doses compared to a single dose. After challenge with B.1.351, there was ~4- to 5-log10 reduction of viral subgenomic RNA and low to undetectable replication in bronchoalveolar lavages in the two-dose vaccine groups, with a 1-log10 reduction in nasal swabs in the 100-µg group. These data establish that a two-dose regimen of mRNA-1273 will be critical for providing upper and lower airway protection against major variants of concern.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Primatas/imunologia , SARS-CoV-2/imunologia , Vacina de mRNA-1273 contra 2019-nCoV , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/virologia , Linhagem Celular , Chlorocebus aethiops , Feminino , Humanos , Macaca mulatta , Masculino , Mesocricetus , Primatas/virologia , RNA Viral/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação/métodos , Células Vero , Carga Viral/métodos
4.
Angew Chem Int Ed Engl ; 63(1): e202313247, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37909921

RESUMO

A new strategy to access α-functionalized alicyclic amines via their corresponding imine-BF3 complexes is reported. Isolable imine-BF3 complexes, readily prepared via dehydrohalogenation of N-bromoamines in a base-promoted/18-crown-6 catalyzed process followed by addition of boron trifluoride etherate, undergo reactions with a wide range of organometallic nucleophiles to afford α-functionalized azacycles. Organozinc and organomagnesium nucleophiles add at ambient temperatures, obviating the need for cryogenic conditions. In situ preparation of imine-BF3 complexes provides access to α-functionalized morpholines and piperazines directly from their parent amines in a single operation. α-Functionalized morpholines can be elaborated further, for instance by installing a second substituent in the α'-position.

5.
N Engl J Med ; 383(16): 1544-1555, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32722908

RESUMO

BACKGROUND: Vaccines to prevent coronavirus disease 2019 (Covid-19) are urgently needed. The effect of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines on viral replication in both upper and lower airways is important to evaluate in nonhuman primates. METHODS: Nonhuman primates received 10 or 100 µg of mRNA-1273, a vaccine encoding the prefusion-stabilized spike protein of SARS-CoV-2, or no vaccine. Antibody and T-cell responses were assessed before upper- and lower-airway challenge with SARS-CoV-2. Active viral replication and viral genomes in bronchoalveolar-lavage (BAL) fluid and nasal swab specimens were assessed by polymerase chain reaction, and histopathological analysis and viral quantification were performed on lung-tissue specimens. RESULTS: The mRNA-1273 vaccine candidate induced antibody levels exceeding those in human convalescent-phase serum, with live-virus reciprocal 50% inhibitory dilution (ID50) geometric mean titers of 501 in the 10-µg dose group and 3481 in the 100-µg dose group. Vaccination induced type 1 helper T-cell (Th1)-biased CD4 T-cell responses and low or undetectable Th2 or CD8 T-cell responses. Viral replication was not detectable in BAL fluid by day 2 after challenge in seven of eight animals in both vaccinated groups. No viral replication was detectable in the nose of any of the eight animals in the 100-µg dose group by day 2 after challenge, and limited inflammation or detectable viral genome or antigen was noted in lungs of animals in either vaccine group. CONCLUSIONS: Vaccination of nonhuman primates with mRNA-1273 induced robust SARS-CoV-2 neutralizing activity, rapid protection in the upper and lower airways, and no pathologic changes in the lung. (Funded by the National Institutes of Health and others.).


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/imunologia , Pneumonia Viral/prevenção & controle , Vacinas Virais/imunologia , Vacina de mRNA-1273 contra 2019-nCoV , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Betacoronavirus/fisiologia , Antígenos CD4 , COVID-19 , Vacinas contra COVID-19 , Infecções por Coronavirus/patologia , Infecções por Coronavirus/terapia , Modelos Animais de Doenças , Relação Dose-Resposta Imunológica , Imunização Passiva , Pulmão/patologia , Pulmão/virologia , Macaca mulatta , Pneumonia Viral/patologia , Pneumonia Viral/terapia , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Linfócitos T/imunologia , Carga Viral , Vacinas Virais/administração & dosagem , Replicação Viral , Soroterapia para COVID-19
6.
Exp Physiol ; 107(12): 1467-1476, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36303408

RESUMO

NEW FINDINGS: What is the main observation in this case? Co-administration of LGD-4033 and MK-677 increased body mass, lean mass and fat mass, while negatively impacting bone, serum lipids, liver enzymes, testosterone (total and free) and, probably, follicle-stimulating hormone. What insights does it reveal? Our cross-sectional data imply that these compounds might alter intramuscular androgenic hormone and receptor concentrations along with promoting muscular strength, when compared with previously published data from trained males. ABSTRACT: LGD-4033, a selective androgen receptor modulator, and MK-677, a growth hormone secretagogue, are being used increasingly amongst recreationally active demographics. However, limited data exist describing their effects on health- and androgen-related biomarkers. The purpose of this case study was to determine changes in body composition and biomarkers during and after continued co-administration of LGD-4033 and MK-677. We also aimed to examine muscular strength and intramuscular androgen-associated biomarkers relative to non-users. A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks. Blood and body composition metrics were obtained pre-, on- and post-cycle. One-repetition maximum leg and bench press, in addition to intramuscular androgens and androgen receptor content, were analysed on-cycle. We observed pre- to on-cycle changes in body composition (body mass, +6.0%; total lean body mass, +3.1%; trunk lean body mass, +6.6%; appendicular lean body mass, +4.3%; total fat mass, +15.4%; trunk fat mass, +2.8%; and appendicular fat mass, +14.8%), bone (bone mineral content, -3.60%; area, -1.1%; and bone mineral density, -2.1%), serum lipid-associated biomarkers (cholesterol, +14.8%; triglycerides, +39.2%; low-density lipoprotein-cholesterol, +40.0%; and high-density lipoprotein-cholesterol, -36.4%), liver-associated biomarkers (aspartate aminotransferase, +95.8%; and alanine aminotransferase, +205.0%) and androgen-associated biomarkers (free testosterone, -85.7%; total testosterone, -62.3%; and sex hormone-binding globulin, -79.6%); however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol. Follicle-stimulating hormone was below clinical reference values on- (1.2 IU/L) and post-cycle (1.3 IU/L). Intramuscular androgen receptor (-44.6%), testosterone (+47.8%) and dihydrotestosterone (+34.4%), in addition to one-repetition maximum leg press and bench press (+39.2 and +32.0%, respectively), were different in the case subject compared with non-users. These data demonstrate that LGD-4033 and MK-677 increase several body composition parameters, whilst negatively impacting bone and several serum biomarkers. Given the sparsity of data in recreationally using demographics, further research is warranted to elucidate the acute and chronic physiological effects of these anabolic agents.


Assuntos
Androgênios , Receptores Androgênicos , Masculino , Humanos , Adulto , Receptores Androgênicos/metabolismo , Estudos Transversais , Composição Corporal , Testosterona , Músculo Esquelético/fisiologia , Biomarcadores , Hormônio Foliculoestimulante , Lipoproteínas LDL
7.
Ann Clin Microbiol Antimicrob ; 21(1): 42, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36192782

RESUMO

BACKGROUND: Bloodstream infections (BSIs), or bacteremia, are responsible for considerable disease burden. Increasing rates of antibiotic resistance and delays in selection of appropriate treatment lead to increased morbidity, mortality, and costs. Due to limitations of current standard treatments, especially for bacteremia caused by resistant pathogens, a systematic literature review (SLR) was conducted to understand the utilization of ceftolozane/tazobactam (C/T) in bacteremia. METHODS: Electronic database searches of EMBASE®, MEDLINE®, CCTR and Northern Lights, as well as hand searches of conference proceedings from the last two annual meetings (i.e., 2018, 2019) of the European Congress of Clinical Microbiological and Infectious Diseases (ECCMID) and the Infectious Diseases Society of America's annual meeting (IDWeek) were conducted. A total of 23 studies reporting on patients with bacteremia receiving C/T were included in the review. RESULTS: Most studies were observational (k = 20 studies), though few interventional studies were also identified (k = 3). Heterogeneity was ubiquitous with respect to source of bacteremia (i.e., primary or secondary), source of infection (for secondary bacteremia), pathogen type, antibiotic resistance, C/T dose, and outcome definitions. This heterogeneity, along with limited data, and small sample sizes (n = 1 to 31) made it difficult to draw any substantial conclusions, though overall results were favorable to C/T with respect to the outcomes of interest. Nineteen studies reported clinical cure or success (primary bacteremia: k = 6, reported range: 33.3% to 100%; secondary bacteremia: k = 8, 60% to 100%; mixed/unspecified bacteremia: k = 10, 50% to 91.7%). Eight studies reported microbiological cure or eradication rates (primary: k = 3, all reporting 100%; secondary: k = 4, 68% to 80%; mixed/unspecified: k = 5, 60% to 80%). Thirteen studies reported mortality (primary: k = 4, 0% to 14%; secondary: k = 7, 0% to 100%; or mixed/unspecified bacteremia: k = 7, 0% to 51.6%). One study each also reported composite clinical response, relapse, hospital re-admission, and hospital length of stay. CONCLUSIONS: Although the available evidence and observed trends for C/T in bacteremia should be interpreted with caution, the direction of effect would support the utilization of C/T for these difficult to treat infections. Future research should supplement the existing evidence by considering the impact of key treatment effect modifiers without contributing to the observed heterogeneity.


Assuntos
Bacteriemia , Doenças Transmissíveis , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Cefalosporinas , Doenças Transmissíveis/tratamento farmacológico , Humanos , Tazobactam/uso terapêutico
8.
J Strength Cond Res ; 35(Suppl 1): S6-S15, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33201154

RESUMO

ABSTRACT: Machek, SB, Cardaci, TD, Wilburn, DT, Cholewinski, MC, Latt, SL, Harris, DR, and Willoughby, DS. Neoprene knee sleeves of varying tightness augment barbell squat one repetition maximum performance without improving other indices of muscular strength, power, or endurance. J Strength Cond Res 35(2S): S6-S15, 2021-Neoprene knee sleeves are commonly used by powerlifters and recreational users but are heavily under-researched. Furthermore, no data exist on whether knee sleeves of varying compressive tightness impact muscular performance similar to commonly used knee wraps, which are both generally effective and more so when increasingly constrictive. Fifteen resistance trained, knee sleeve naive, recreational weight lifting men (22.1 ± 4.1 years; 177.5 ± 5.9 cm; 87.8 ± 7.8 kg) visited the laboratory on 3 separate occasions one week apart, assigned in a randomized, crossover, and counterbalanced fashion to either a minimally supportive control sleeve (CS) condition, a manufacturer-recommended sizing neoprene knee sleeve ("normal" sleeve; NS), or a one size smaller (than NS) neoprene knee sleeve (tighter sleeve [TS]). On each visit, subjects sequentially completed vertical jump (countermovement and squat jumps for both peak and mean power), one repetition maximum (1RM) barbell squat, and GymAware assessments (peak power, peak velocity, and dip) at 90% (reported) and 100% (tested) 1RM as well as one-leg extension (1RM, repetitions to failure, and total volume load at 75% 1RM) tests. All data were analyzed using one-way repeated measures analysis of variance at p < 0.05. Analysis revealed a significant condition effect on barbell squat 1RM (p = 0.003; η2 = 0.339), whereby both NS (p = 0.044; 166 ± 24 kg) and TS (p = 0.019; 166 ± 21 kg) outperformed CS (161 ± 22 kg), with no difference between neoprene sleeves. Conversely, no other tested parameters differed between knee sleeve conditions (p ≥ 0.05). The present results demonstrate that neoprene knee sleeves may function independent of tightness, relative to recommended sizing and ultimately unlike knee wraps. Furthermore, the singular benefits observed on barbell squat maximal strength potentially suggests an exercise-specific benefit yet to be fully elucidated.


Assuntos
Neopreno , Treinamento Resistido , Humanos , Joelho , Masculino , Força Muscular , Músculo Esquelético , Levantamento de Peso
9.
Angew Chem Int Ed Engl ; 59(38): 16668-16674, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32525593

RESUMO

Selective monofunctionalization of substrates with distant, yet equally reactive functional groups is difficult to achieve, as it requires the second functional group to selectively modulate its reactivity once the first functional group has reacted. We now show that mechanically interlocked catalytic rings can effectively regulate the reactivity of stoppering groups in rotaxanes over a distance of about 2 nm. Our mechanism of communication is enabled by a unique interlocked design, which effectively removes the catalytic rings from the substrates by fast dethreading as soon as the first reaction has taken place. Our method not only led to a rare example of selective monofunctionalization, but also to a "molecular if function". Overall, the study presents a way to get distant functional groups to communicate with each other in a reaction-history-dependent manner by creating linkers that can ultimately perform logical operations at the molecular level.

10.
Psychol Med ; 48(5): 751-764, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28933314

RESUMO

BACKGROUND: Cognitive remediation (CR) training has emerged as a promising approach to improving cognitive deficits in schizophrenia and related psychosis. The limited availability of psychological services for psychosis is a major barrier to accessing this intervention however. This study investigated the effectiveness of a low support, remotely accessible, computerised working memory (WM) training programme in patients with psychosis. METHODS: Ninety patients were enrolled into a single blind randomised controlled trial of CR. Effectiveness of the intervention was assessed in terms of neuropsychological performance, social and occupational function, and functional MRI 2 weeks post-intervention, with neuropsychological and social function again assessed 3-6 months post-treatment. RESULTS: Patients who completed the intervention showed significant gains in both neuropsychological function (measured using both untrained WM and episodic task performance, and a measure of performance IQ), and social function at both 2-week follow-up and 3-6-month follow-up timepoints. Furthermore, patients who completed MRI scanning showed improved resting state functional connectivity relative to patients in the placebo condition. CONCLUSIONS: CR training has already been shown to improve cognitive and social function in patient with psychosis. This study demonstrates that, at least for some chronic but stable outpatients, a low support treatment was associated with gains that were comparable with those reported for CR delivered entirely on a 1:1 basis. We conclude that CR has potential to be delivered even in services in which psychological supports for patients with psychosis are limited.


Assuntos
Disfunção Cognitiva/reabilitação , Remediação Cognitiva/métodos , Memória de Curto Prazo/fisiologia , Avaliação de Resultados em Cuidados de Saúde , Transtornos Psicóticos/reabilitação , Esquizofrenia/reabilitação , Telemedicina/métodos , Adulto , Disfunção Cognitiva/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/complicações , Esquizofrenia/complicações , Método Simples-Cego , Terapia Assistida por Computador/métodos
11.
Med Vet Entomol ; 29(1): 1-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25087926

RESUMO

The U.K. has not yet experienced a confirmed outbreak of mosquito-borne virus transmission to people or livestock despite numerous autochthonous epizootic and human outbreaks of mosquito-borne diseases on the European mainland. Indeed, whether or not British mosquitoes are competent to transmit arboviruses has not been established. Therefore, the competence of a local (temperate) British mosquito species, Ochlerotatus detritus (=Aedes detritus) (Diptera: Culicidae) for transmission of a member of the genus Flavivirus, Japanese encephalitis virus (JEV) as a model for mosquito-borne virus transmission was assessed. The JEV competence in a laboratory strain of Culex quinquefasciatus (Diptera: Culicidae), a previously incriminated JEV vector, was also evaluated as a positive control. Ochlerotatus detritus adults were reared from field-collected juvenile stages. In oral infection bioassays, adult females developed disseminated infections and were able to transmit virus as determined by the isolation of virus in saliva secretions. When pooled at 7-21 days post-infection, 13% and 25% of O. detritus were able to transmit JEV when held at 23 °C and 28 °C, respectively. Similar results were obtained for C. quinquefasciatus. To our knowledge, this study is the first to demonstrate that a British mosquito species, O. detritus, is a potential vector of an exotic flavivirus.


Assuntos
Vírus da Encefalite Japonesa (Espécie)/fisiologia , Encefalite Japonesa/transmissão , Insetos Vetores/virologia , Ochlerotatus/virologia , Aedes/fisiologia , Aedes/virologia , Animais , Encefalite Japonesa/virologia , Inglaterra , Feminino , Temperatura Alta , Humanos , Insetos Vetores/fisiologia , Ochlerotatus/fisiologia
13.
J Osteopath Med ; 124(10): 429-435, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38837124

RESUMO

CONTEXT: Fryette's mechanics is taught as a simplistic model of coupled vertebral movement, fundamental in osteopathic practice. This study seeks to better understand the likelihood of Fryette's model by calculating vertebral orientation in computed tomography (CT) scans. Given previous findings of low angular coupled movements during overall spinal motion, static calculations provide a unique perspective on the likelihood of Fryette's mechanics. OBJECTIVES: This analysis aims to evaluate the efficacy of Fryette's principles in predicting vertebral positioning in CT scans by comparing their 3-dimensional (3D) orientation to movements described by Fryette. METHODS: 3D models of 953 thoracic and lumbar vertebrae were obtained from 82 CT scans within the VerSe`20 open-source dataset. A stepwise algorithm generated three unique symmetry planes for each vertebra, offering 3D angular orientation with respect to the vertebral level below. A total of 422 vertebrae were omitted from the analysis due to the presence of pathologies significant enough to affect their motion, inaccurate symmetry plane calculations, or absence of vertebral level below. The remaining 531 vertebra were analyzed to compare quantitative coupled positioning against expected coupled spinal movements in line with Fryette's mechanics. One-sample proportional z-scoring was implemented for all vertebral levels with an ∝=0.05 and a null hypothesis of Fryette's primed positioning occurring by chance of 50 %. Further analysis was performed with individual z-scoring for each individual level to see which levels were statistically significant. RESULTS: Data from the VerSe`20 dataset revealed that 56.9 % of successfully analyzed vertebrae demonstrated positions compatible with Fryette's mechanics (p=0.0014, power=89 %). The 302 vertebral levels that did display coupled positioning consisted of Type I (166 vertebrae) and Type II (136 vertebrae) compatible with Fryette's mechanics. Levels that demonstrated statistical significance consisted of T5 (p=0, power=99 %), T6 (p=0.0023, power=77 %), T7 (p=0.041, power=46 %), and T10 (p=0.017, power=60 %). CONCLUSIONS: Our analysis suggests that the static positions of vertebrae in CT scans may align with Fryette's descriptions, although not very often. Notably, vertebral levels T5-T7 and T10 exhibit strong evidence of their static positions aligning with expected movements, warranting further investigation into the Fryette phenomenon at these levels. Future studies should explore the dynamic implications of these findings to enhance our understanding of spinal biomechanics.


Assuntos
Imageamento Tridimensional , Vértebras Lombares , Vértebras Torácicas , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Vértebras Lombares/diagnóstico por imagem , Imageamento Tridimensional/métodos , Vértebras Torácicas/diagnóstico por imagem , Fenômenos Biomecânicos/fisiologia , Masculino , Feminino , Movimento/fisiologia , Pessoa de Meia-Idade , Adulto , Algoritmos , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/fisiologia , Coluna Vertebral/anatomia & histologia , Idoso
14.
Med Sci Sports Exerc ; 56(3): 476-485, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38051142

RESUMO

PURPOSE: Long-chain omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) may enhance recovery from exercise-induced muscle damage (EIMD). However, it is unclear if the effects are due to EPA, DHA, or both. The purpose of this investigation was to examine the effect of EPA + DHA, EPA, and DHA compared with placebo (PL) on muscular recovery. METHODS: Thirty males were randomized to 4 g·d -1 EPA + DHA ( n = 8), EPA ( n = 8), DHA ( n = 7), or PL ( n = 7). After 7-wk supplementation, a downhill running (20 min, 70% V̇O 2max , -16% gradient) plus jumping lunges (5 × 20 reps, 2-min rest intervals) muscle damage protocol was performed. Indices of muscle damage, soreness, muscle function, and inflammation were measured at baseline and throughout recovery. The omega-3 index (O3i; %EPA + %DHA in erythrocytes) was used to track tissue EPA and DHA status. RESULTS: After supplementation, the O3i was significantly higher than PL in all experimental groups ( P < 0.001). Leg press performance was lower in the PL group at 24 h compared with EPA ( P = 0 .019) and at 72 h for EPA ( P = 0.004) and DHA ( P = 0 .046). Compared with PL, muscle soreness was lower in the DHA ( P = 0.015) and EPA ( P = 0.027) groups at 48 h. Albeit nonsignificant, EPA + DHA tended to attenuate muscle soreness ( d = 1.37) and leg strength decrements ( d = 0.75) compared with PL. Jump performance and power metrics improved more rapidly in the EPA and DHA groups (time effects: P < 0.001). Measures of inflammation, range of motion, and muscle swelling were similar between groups ( P > 0.05). CONCLUSIONS: Compared with PL, 4 g·d -1 of EPA or DHA for 52 d improves certain aspects of recovery from EIMD. EPA + DHA did not clearly enhance recovery. Equivalent dosing of EPA + DHA may blunt the performance effects observed in EPA or DHA alone.


Assuntos
Ácido Eicosapentaenoico , Ácidos Graxos Ômega-3 , Humanos , Masculino , Ácido Eicosapentaenoico/farmacologia , Ácidos Docosa-Hexaenoicos , Mialgia , Suplementos Nutricionais , Ácidos Graxos Ômega-3/farmacologia , Inflamação , Músculos
15.
Chem Sci ; 15(13): 4860-4870, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38550687

RESUMO

Geometric isomerism in mechanically interlocked systems-which arises when the axle of a mechanically interlocked molecule is oriented, and the macrocyclic component is facially dissymmetric-can provide enhanced functionality for directional transport and polymerization catalysis. We now introduce a kinetically controlled strategy to control geometric isomerism in [2]rotaxanes. Our synthesis provides the major geometric isomer with high selectivity, broadening synthetic access to such interlocked structures. Starting from a readily accessible [2]rotaxane with a symmetrical axle, one of the two stoppers is activated selectively for stopper exchange by the substituents on the ring component. High selectivities are achieved in these reactions, based on coupling the selective formation reactions leading to the major products with inversely selective depletion reactions for the minor products. Specifically, in our reaction system, the desired (major) product forms faster in the first step, while the undesired (minor) product subsequently reacts away faster in the second step. Quantitative 1H NMR data, fit to a detailed kinetic model, demonstrates that this effect (which is conceptually closely related to minor enantiomer recycling and related processes) can significantly improve the intrinsic selectivity of the reactions. Our results serve as proof of principle for how multiple selective reaction steps can work together to enhance the stereoselectivity of synthetic processes forming complex mechanically interlocked molecules.

16.
Nat Commun ; 15(1): 6894, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39134521

RESUMO

SARS-CoV-2 has the capacity to evolve mutations that escape vaccine- and infection-acquired immunity and antiviral drugs. A variant-agnostic therapeutic agent that protects against severe disease without putting selective pressure on the virus would thus be a valuable biomedical tool that would maintain its efficacy despite the ongoing emergence of new variants. Here, we challenge male rhesus macaques with SARS-CoV-2 Delta-the most pathogenic variant in a highly susceptible animal model. At the time of challenge, we also treat the macaques with aerosolized RBD-62, a protein developed through multiple rounds of in vitro evolution of SARS-CoV-2 RBD to acquire 1000-fold enhanced ACE2 binding affinity. RBD-62 treatment equivalently suppresses virus replication in both upper and lower airways, a phenomenon not previously observed with clinically approved vaccines. Importantly, RBD-62 does not block the development of virus-specific T- and B-cell responses and does not elicit anti-drug immunity. These data provide proof-of-concept that RBD-62 can prevent severe disease from a highly virulent variant.


Assuntos
Enzima de Conversão de Angiotensina 2 , Antivirais , COVID-19 , SARS-CoV-2 , Replicação Viral , Animais , Humanos , Masculino , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Antivirais/farmacologia , Chlorocebus aethiops , COVID-19/virologia , COVID-19/imunologia , COVID-19/prevenção & controle , Tratamento Farmacológico da COVID-19 , Modelos Animais de Doenças , Macaca mulatta , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/fisiologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Células Vero , Replicação Viral/efeitos dos fármacos
17.
Insect Mol Biol ; 22(2): 211-32, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23398403

RESUMO

As important vectors of human disease, phlebotomine sand flies are of global significance to human health, transmitting several emerging and re-emerging infectious diseases. The most devastating of the sand fly transmitted infections are the leishmaniases, causing significant mortality and morbidity in both the Old and New World. Here we present the first global transcriptome analysis of the Old World vector of cutaneous leishmaniasis, Phlebotomus papatasi (Scopoli) and compare this transcriptome to that of the New World vector of visceral leishmaniasis, Lutzomyia longipalpis. A normalized cDNA library was constructed using pooled mRNA from Phlebotomus papatasi larvae, pupae, adult males and females fed sugar, blood, or blood infected with Leishmania major. A total of 47 615 generated sequences was cleaned and assembled into 17 120 unique transcripts. Of the assembled sequences, 50% (8837 sequences) were classified using Gene Ontology (GO) terms. This collection of transcripts is comprehensive, as demonstrated by the high number of different GO categories. An in-depth analysis revealed 245 sequences with putative homology to proteins involved in blood and sugar digestion, immune response and peritrophic matrix formation. Twelve of the novel genes, including one trypsin, two peptidoglycan recognition proteins (PGRP) and nine chymotrypsins, have a higher expression level during larval stages. Two novel chymotrypsins and one novel PGRP are abundantly expressed upon blood feeding. This study will greatly improve the available genomic resources for P. papatasi and will provide essential information for annotation of the full genome.


Assuntos
Perfilação da Expressão Gênica , Proteínas de Insetos/genética , Phlebotomus/genética , Sequência de Aminoácidos , Animais , Sangue/parasitologia , Quimotripsina/genética , Quimotripsina/metabolismo , Etiquetas de Sequências Expressas , Feminino , Biblioteca Gênica , Insetos Vetores/genética , Leishmania major , Masculino , Dados de Sequência Molecular , Filogenia , Polimorfismo de Nucleotídeo Único , Psychodidae/genética , Homologia de Sequência de Aminoácidos , Tripsina/genética , Tripsina/metabolismo
18.
Mycologia ; 105(2): 422-35, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23080024

RESUMO

Xerocomus cyaneibrunnescens, Xerocomus potaroensis, and Xerocomus parvogracilis (Boletales, Basidiomycota) are described as new species from the Pakaraima Mountains of Guyana, in the central Guiana Shield region. These boletes occur in neotropical forests dominated by ectomycorrhizal (ECM) trees in the genus Dicymbe (Fabaceae subfam. Caesalpinioideae). Each species produced basidiomata during a multi-year plot survey, and each was confirmed as an ECM symbiont with one or more leguminous host plant species in Guyana.


Assuntos
Basidiomycota/classificação , Fabaceae/microbiologia , Micorrizas/classificação , Sequência de Bases , Basidiomycota/citologia , Basidiomycota/genética , Basidiomycota/isolamento & purificação , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Carpóforos/citologia , Guiana , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Micorrizas/citologia , Micorrizas/genética , Micorrizas/isolamento & purificação , Raízes de Plantas/microbiologia , Análise de Sequência de DNA , Especificidade da Espécie , Esporos Fúngicos/citologia , Simbiose , Árvores
19.
J Chem Theory Comput ; 19(21): 7873-7881, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37877553

RESUMO

DNA nanostructures have emerged as promising nanomedical tools due to their biocompatibility and tunable behavior. Recent work has shown that DNA nanocages decorated with organic dendrimers strongly bind human serum albumin (HSA), yet the dynamic structures of these complexes remain uncharacterized. This theoretical and computational investigation elucidates the fuzzy interactions between dendritically functionalized cubic DNA nanocages and HSA. The dendrimer-HSA interactions occur via nonspecific binding with the protein thermodynamically and kinetically free to cross the open faces of the cubic scaffold. However, the rigidity of the DNA scaffold prevents the binding energetics from scaling with the number of dendrimers. These discoveries not only provide a useful framework by which to model general interactions of DNA nanostructures complexed with serum proteins but also give valuable molecular insight into the design of next-generation DNA nanomedicines.


Assuntos
Dendrímeros , Nanoestruturas , Albumina Sérica Humana , Humanos , Dendrímeros/química , DNA/química , Nanoestruturas/química
20.
Chem Sci ; 14(40): 11228-11236, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37860640

RESUMO

Synthesis of olefin-styrene copolymers with defined architecture is challenging due to the limitations associated with the inherent reactivity ratios for these monomers in radical or metal-catalyzed polymerizations. Herein, we developed a straightforward approach to alternating styrene-propylene and styrene-ethylene copolymers by combining radical polymerizations and powerful post-polymerization modification reactions. We employed reversible addition-fragmentation chain transfer (RAFT) copolymerization between styrene derivatives and saccharin (meth)acrylamide to generate alternating copolymers. Once polymerized, the amide bond of the saccharin monomers was highly reactive toward hydrolysis, an observation exploited to obtain alternating styrene-acrylic acid/methacrylic acid copolymers. Subsequent mild decarboxylation of the (meth)acrylic acid groups in the presence of a photocatalyst and a hydrogen source under visible light resulted in the styrene-alt-ethylene/propylene copolymers. Alternating copolymers comprised of either propylene or ethylene units alternating with functional styrene derivatives were also prepared, illustrating the compatibility of this approach for functional polymer synthesis. Finally, the thermal properties of the alternating copolymers were compared to those from statistical copolymer analogs to elucidate the effect of microarchitecture and styrene substituents on the glass transition temperature.

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