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1.
PLoS Med ; 20(6): e1004157, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37384638

RESUMO

BACKGROUND: Patients with chronic lymphocytic leukemia (CLL) have reduced seroconversion rates and lower binding antibody (Ab) and neutralizing antibody (NAb) titers than healthy individuals following Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) mRNA vaccination. Here, we dissected vaccine-mediated humoral and cellular responses to understand the mechanisms underlying CLL-induced immune dysfunction. METHODS AND FINDINGS: We performed a prospective observational study in SARS-CoV-2 infection-naïve CLL patients (n = 95) and healthy controls (n = 30) who were vaccinated between December 2020 and June 2021. Sixty-one CLL patients and 27 healthy controls received 2 doses of the Pfizer-BioNTech BNT162b2 vaccine, while 34 CLL patients and 3 healthy controls received 2 doses of the Moderna mRNA-1273 vaccine. The median time to analysis was 38 days (IQR, 27 to 83) for CLL patients and 36 days (IQR, 28 to 57) for healthy controls. Testing plasma samples for SARS-CoV-2 anti-spike and receptor-binding domain Abs by enzyme-linked immunosorbent assay (ELISA), we found that all healthy controls seroconverted to both antigens, while CLL patients had lower response rates (68% and 54%) as well as lower median titers (23-fold and 30-fold; both p < 0.001). Similarly, NAb responses against the then prevalent D614G and Delta SARS-CoV-2 variants were detected in 97% and 93% of controls, respectively, but in only 42% and 38% of CLL patients, who also exhibited >23-fold and >17-fold lower median NAb titers (both p < 0.001). Interestingly, 26% of CLL patients failed to develop NAbs but had high-titer binding Abs that preferentially reacted with the S2 subunit of the SARS-CoV-2 spike. Since these patients were also seropositive for endemic human coronaviruses (HCoVs), these responses likely reflect cross-reactive HCoV Abs rather than vaccine-induced de novo responses. CLL disease status, advanced Rai stage (III-IV), elevated serum beta-2 microglobulin levels (ß2m >2.4 mg/L), prior therapy, anti-CD20 immunotherapy (<12 months), and intravenous immunoglobulin (IVIg) prophylaxis were all predictive of an inability to mount SARS-CoV-2 NAbs (all p ≤ 0.03). T cell response rates determined for a subset of participants were 2.8-fold lower for CLL patients compared to healthy controls (0.05, 95% CI 0.01 to 0.27, p < 0.001), with reduced intracellular IFNγ staining (p = 0.03) and effector polyfunctionality (p < 0.001) observed in CD4+ but not in CD8+ T cells. Surprisingly, in treatment-naïve CLL patients, BNT162b2 vaccination was identified as an independent negative risk factor for NAb generation (5.8, 95% CI 1.6 to 27, p = 0.006). CLL patients who received mRNA-1273 had 12-fold higher (p < 0.001) NAb titers and 1.7-fold higher (6.5, 95% CI 1.3 to 32, p = 0.02) response rates than BNT162b2 vaccinees despite similar disease characteristics. The absence of detectable NAbs in CLL patients was associated with reduced naïve CD4+ T cells (p = 0.03) and increased CD8+ effector memory T cells (p = 0.006). Limitations of the study were that not all participants were subjected to the same immune analyses and that pre-vaccination samples were not available. CONCLUSIONS: CLL pathogenesis is characterized by a progressive loss of adaptive immune functions, including in most treatment-naïve patients, with preexisting memory being preserved longer than the capacity to mount responses to new antigens. In addition, higher NAb titers and response rates identify mRNA-1273 as a superior vaccine for CLL patients.


Assuntos
COVID-19 , Leucemia Linfocítica Crônica de Células B , Humanos , Vacina de mRNA-1273 contra 2019-nCoV , Vacina BNT162 , Estudos Prospectivos , SARS-CoV-2 , COVID-19/prevenção & controle , Vacinação
2.
medRxiv ; 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36597532

RESUMO

Chronic lymphocytic leukemia (CLL) patients have lower seroconversion rates and antibody titers following SARS-CoV-2 vaccination, but the reasons for this diminished response are poorly understood. Here, we studied humoral and cellular responses in 95 CLL patients and 30 healthy controls after two BNT162b2 or mRNA-2173 mRNA immunizations. We found that 42% of CLL vaccinees developed SARS-CoV-2-specific binding and neutralizing antibodies (NAbs), while 32% had no response. Interestingly, 26% were seropositive, but had no detectable NAbs, suggesting the maintenance of pre-existing endemic human coronavirus-specific antibodies that cross-react with the S2 domain of the SARS-CoV-2 spike. These individuals had more advanced disease. In treatment-naïve CLL patients, mRNA-2173 induced 12-fold higher NAb titers and 1.7-fold higher response rates than BNT162b2. These data reveal a graded loss of immune function, with pre-existing memory being preserved longer than the capacity to respond to new antigens, and identify mRNA-2173 as a superior vaccine for CLL patients.

3.
Am J Surg ; 222(4): 780-785, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33541690

RESUMO

BACKGROUND: Informed consent forms consist of large blocks of written information that may be difficult for patients to understand. Visual teaching aids are promising, however, they have not been studied as a pre-operative educational tool for common surgical procedures. We pilot tested the use of a visual teaching aid during the informed consent process for a colectomy. METHODS: A randomized pilot study was performed. Participants were randomized into the visual teaching aid group or standard care. Following the consent process, participants were questioned about potential surgical complications, anxiety, satisfaction, and understanding. RESULTS: 30 participants were enrolled. Potential complication recall and patient-reported understanding were improved in the visual group (p = 0.01, p = 0.03). Anxiety levels were reduced in the visual group (p = 0.02). No statistically significant data were found for satisfaction (p = 0.75). CONCLUSIONS: Utilizing a visual teaching aid during the consent process for colectomy increases patient recall of risks, reduces anxiety, and improves understanding.


Assuntos
Ansiedade/prevenção & controle , Recursos Audiovisuais , Colectomia , Letramento em Saúde , Educação de Pacientes como Assunto , Idoso , Alabama , Compreensão , Feminino , Humanos , Consentimento Livre e Esclarecido , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Projetos Piloto , Complicações Pós-Operatórias
4.
Macromol Rapid Commun ; 38(2)2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27873447

RESUMO

This report demonstrates the electroless deposition of Ni onto micropatterns of poly (acrylic acid) (PAA) photografted to phthalimide-terminated self-assembled monolayers (SAMs). PAA is spin-coated onto phthalimide SAMs and covered with a photomask. UV irradiation selectively binds PAA to exposed regions of the surface, allowing PAA on unexposed regions to be rinsed off. A Pd catalyst is then selectively adsorbed to regions of the surface where PAA is bound. The adsorbed catalyst selectively initiates Ni plating upon immersion of the substrate into a Ni(SO4 ) bath.


Assuntos
Resinas Acrílicas/química , Níquel/química , Adsorção , Catálise , Estrutura Molecular , Processos Fotoquímicos
5.
Photochem Photobiol ; 90(2): 394-401, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24256104

RESUMO

Small molecules representing common synthetic polymers were subjected to photochemically induced hydrogen abstraction by benzophenone. Reactions were monitored using (1) H NMR to query the factors that influence preferential abstraction of protons in unique chemical environments. Differences in bond dissociation energies do not fully explain the observed hydrogen abstraction preferences. To that end, we identify contributions to abstraction from prereactive complexation, radical stability, steric effects and charge transfer effects. Using representative small molecule model compounds in lieu of polymeric materials is a novel approach to understanding photochemical reaction in polymers; however, it cannot probe the contributions of macromolecular effects--e.g. polymer rigidity or side chain and backbone mobility--to preferential hydrogen abstraction.


Assuntos
Hidrogênio/química , Modelos Químicos , Mimetismo Molecular , Polímeros/química , Espectroscopia de Prótons por Ressonância Magnética
6.
World Neurosurg ; 77(2): 349-51, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22120387

RESUMO

OBJECTIVE: To elucidate further the anatomy of focal enlargements that have been observed along the spinal accessory nerve (SAN) as it courses within the posterior cranial fossa. METHODS: Dissection of the posterior cranial fossa was performed on 27 adult cadavers with attention to the SAN and any focal enlargements associated with it. RESULTS: Grossly, four specimens (14.8%) were found to have focal enlargements associated with the SAN within the posterior cranial fossa. These structures were in intimate contact with the dorsal aspect of the spinal portion of the SAN in all specimens and measured a mean diameter of 1.9 mm. One right-sided male specimen had two focal enlargements. All focal enlargements were found within 1 cm of the foramen magnum. Histologically, no ganglion or neuronal cells were identified within these focal enlargements in any specimen. These focal enlargements are best described as ectopic glial nests or heterotopias within the leptomeninges around the SAN. CONCLUSIONS: The focal enlargements located along the SAN should not be termed ganglia. These structures do not contain neural structures and should not be mistaken for pathology of the posterior fossa.


Assuntos
Nervo Acessório/patologia , Nervo Acessório/cirurgia , Gânglios Espinais/patologia , Gânglios Espinais/cirurgia , Procedimentos Neurocirúrgicos , Adulto , Idoso , Cadáver , Fossa Craniana Posterior/patologia , Fossa Craniana Posterior/cirurgia , Feminino , Forame Magno/patologia , Forame Magno/cirurgia , Lateralidade Funcional , Humanos , Masculino , Meninges/patologia , Meninges/cirurgia , Pessoa de Meia-Idade , Fixação de Tecidos
7.
J Neurosurg Spine ; 15(1): 55-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21476797

RESUMO

OBJECTIVE: Assimilation of the atlas to the occiput may result in symptoms that are often compressive in nature around the outlet of the foramen magnum. The aim of the present study was to elucidate the morphological features of the bone through this foramen. METHODS: Thirteen adult skulls with atlantooccipital fusion underwent morphometrical analysis of the outlet of the foramen magnum. RESULTS: All specimens but one were found to have a decreased area of the outlet of the foramen magnum. In those 12 specimens, a decrease of 15%-35% was seen. Fusions of the atlas that were based primarily along the anterior rim of the foramen magnum resulted in more obstruction of its outlet. In general, the horizontal diameters of the outlet of these foramina were more decreased from the normal range. CONCLUSIONS: These findings demonstrate that in the majority of cases, assimilation of the atlas to the occiput results in a compromised outlet of the foramen magnum.


Assuntos
Articulação Atlantoccipital/anormalidades , Atlas Cervical/anormalidades , Forame Magno/anormalidades , Feminino , Humanos , Masculino
8.
Photochem Photobiol Sci ; 9(8): 1082-4, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20526506

RESUMO

The cycloadducts of tethered naphthalene and anthracene derivatives undergo photochemical ring opening to an electronically excited product with adiabatic yields up to 90%.

9.
Nat Chem ; 1(8): 587-90, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21378942
10.
Org Lett ; 10(24): 5509-12, 2008 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-19053738

RESUMO

The bimolecular quenching rate constants of singlet oxygen ((1)O2) by cubane and cubane derivatives were determined and found to be in the order of 10(3)-10(4) M(-1) s(-1). These values represent larger values than expected for aliphatic alkanes as a model for C-H vibrational deactivation. This result is explained by the occurrence of two different deactivation mechanisms: energy transfer to cubane C-H vibrational modes and the formation of a charge-transfer complex between (1)O2 and cubane ((1)O2(*-)...cubane(*+)).

11.
J Chem Phys ; 125(16): 164314, 2006 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-17092080

RESUMO

The laser-induced fluorescence and action spectra of I2 in a helium supersonic expansion have been recorded in the I2 B-X, 20-0 region. Two features are identified within the spectra. The lower-energy feature arises from transitions between states that are localized in a T-shaped conformation on both the X- and B-state potentials. The higher-energy feature reflects transitions from states that are localized in a linear conformation on the X state to states that have energies that are larger than the barrier for free rotation of the rare gas atom about the I2 molecule on the B-state potential. Ground-state binding energies of 16.6(6) and 16.3(6) cm-1 were determined for the T-shaped and linear conformers, respectively. These spectra are compared to those calculated using the experimentally determined rotational temperatures. Based on the agreement between the experimental and calculated spectra, the binding energies of the J'=0 states with 0 and 2-6 quanta of excitation in the He...I2 bending mode on the B state were determined. Several models for the B-state potential were used to investigate the origins of the shape of the contour of the higher-energy feature in the spectra for He...I2 and He...Br2. The shape of the contours was found to be relatively insensitive to the choice of potential. This leads us to believe that the spectra of these systems are relatively insensitive to the parameters of the B-state potential energy surface and are more sensitive to properties of the halogen molecule.

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