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1.
J Virol ; 97(5): e0188822, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-36975793

RESUMO

Zaïre ebolavirus (EBOV) causes Ebola virus disease (EVD), a devastating viral hemorrhagic fever in humans. Nonhuman primate (NHP) models of EVD traditionally use intramuscular infection with higher case fatality rates and reduced mean time-to-death compared to contact transmission typical of human cases of EVD. A cynomolgus macaque model of oral and conjunctival EBOV was used to further characterize the more clinically relevant contact transmission of EVD. NHPs challenged via the oral route had an overall 50% survival rate. NHPs challenged with a target dose of 1 × 102 PFU or 1 × 104 PFU of EBOV via the conjunctival route had 40% and 100% mortality, respectively. Classic signs of lethal EVD-like disease were observed in all NHPs that succumbed to EBOV infection including viremia, hematological abnormalities, clinical chemistries indicative of hepatic and renal disease, and histopathological findings. Evidence of EBOV viral persistence in the eye was observed in NHPs challenged via the conjunctival route. IMPORTANCE This study is the first to examine the Kikwit strain of EBOV, the most commonly used strain, in the gold-standard macaque model of infection. Additionally, this is the first description of the detection of virus in the vitreous fluid, an immune privileged site that has been proposed as a viral reservoir, following conjunctival challenge. The oral and conjunctival macaque challenge model of EVD described here more faithfully recapitulates the prodrome that has been reported for human EVD. This work paves the way for more advanced studies to model contact transmission of EVD, including early events in mucosal infection and immunity, as well as the establishment of persistent viral infection and the emergence from these reservoirs.


Assuntos
Ebolavirus , Doença pelo Vírus Ebola , Animais , Humanos , Ebolavirus/fisiologia , Doença pelo Vírus Ebola/transmissão , Macaca fascicularis , Modelos Animais de Doenças , Túnica Conjuntiva/virologia , Transmissão de Doença Infecciosa
2.
J Virol ; 96(18): e0130522, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36094313

RESUMO

Curriculum guidelines for virology are needed to best guide student learning due to the continuous and ever-increasing volume of virology information, the need to ensure that undergraduate and graduate students have a foundational understanding of key virology concepts, and the importance in being able to communicate that understanding to both other virologists and nonvirologists. Such guidelines, developed by virology educators and the American Society for Virology Education and Career Development Committee, are described herein.


Assuntos
Currículo , Universidades , Virologia , Educação de Pós-Graduação , Estados Unidos , Virologia/educação
3.
Artigo em Inglês | MEDLINE | ID: mdl-37796840

RESUMO

OBJECTIVES: Idiopathic inflammatory myopathies (IIMs) are heterogeneous diseases characterized by skeletal muscle inflammation associated with cutaneous, pulmonary, and/or other visceral organ involvement. Intravenous immunoglobulin (IVIG) has been recommended as an adjunct therapy for IIM patients refractory to conventional therapy. However, IVIG has high resource needs and increased risk of adverse reactions. Subcutaneous immunoglobulin (SCIG) therapy has been used as an alternative to IVIG in primary immunodeficiencies and neuroinflammatory disorders. We assessed the satisfaction, patient preference and effectiveness in IIM patients transitioned from IVIG to SCIG. METHODS: We retrospectively reviewed consecutive 20 patients with IIM who were transitioned from IVIG to SCIG therapy for >12 months. Patient preference between IVIG vs SCIG was surveyed using a questionnaire previously used in studies with neuroinflammatory conditions. In addition, disease flares, changes in immunosuppression, cumulative prednisone doses and global disease activity were evaluated using the Myositis Intention to Treat Index (MITAX) 12-months prior to- and post-SCIG initiation. RESULTS: Most patients (78.9%) preferred SCIG over IVIG and preferred home-based therapies to hospital-based therapies. There was no significant difference in global disease activity (MITAX 3.31 vs 3.02) nor in cumulative steroid doses 12-months prior to- or post-SCIG initiation. Three patients experienced disease flares, 5 escalated in immunosuppression, while 4 patients deescalated in immunosuppressive medications. CONCLUSIONS: SCIG is preferred by most patients over IVIG without a substantial increased disease activity or need for additional corticosteroids. Future cost effectiveness studies may provide an additional rationale for utilizing SCIG over IVIG for maintenance therapy for IIM.

4.
Rheumatology (Oxford) ; 62(9): 3059-3066, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36625513

RESUMO

OBJECTIVES: Damage accrual in SSc can be tracked using the Scleroderma Clinical Trials Consortium Damage Index (DI). Our goal was to develop a prediction model for damage accrual in SSc patients with early disease. METHODS: Using patients with <2 years disease duration from Canada and Australia as a derivation cohort, and from the Netherlands as a validation cohort, we used group-based trajectory modelling (GBTM) to determine 'good' and 'bad' latent damage trajectories. We developed a prediction model from this analysis and applied it to patients from derivation and validation cohorts. We plotted the actual DI trajectories of the patients predicted to be in 'good' or 'bad' groups. RESULTS: We found that the actual trajectories of damage accumulation for lcSSc and dcSSc were very different, so we studied each subset separately. GBTM found two distinct trajectories in lcSSc and three in dcSSc. We collapsed the two worse trajectories in the dcSSc into one group and developed a prediction model for inclusion in either 'good' or 'bad' trajectories. The performance of models using only baseline DI and sex was excellent with ROC AUC of 0.9313 for lcSSc and 0.9027 for dcSSc. Using this model, we determined whether patients would fall into 'good' or 'bad' trajectory groups and then plotted their actual trajectories which showed clear differences between the predicted 'good' and 'bad' cases in both derivation and validation cohorts. CONCLUSIONS: A simple model using only cutaneous subset, baseline DI and sex can predict damage accumulation in early SSc.


Assuntos
Esclerodermia Difusa , Esclerodermia Localizada , Escleroderma Sistêmico , Humanos , Pele , Administração Cutânea , Canadá
5.
Biochemistry ; 61(11): 1103-1112, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35522994

RESUMO

The C-terminal 14-16 residues of human troponin T are required for full inactivation, and they prevent full activation at saturating Ca2+. Basic residues within that C-terminal region of TnT are essential for its function, but the mechanism of action is unknown. That region of TnT is natively disordered and does not appear in reconstructions of the troponin structure. We used Förster resonance energy transfer to determine if the C-terminal basic region of TnT alters transitions of TnI or if it operates independently. We also examined Ca2+-dependent changes in the C-terminal region of TnT itself. Probes on TnI-143 (inhibitory region) and TnI-159 (switch region) moved away from sites on actin and tropomyosin and toward TnC-84 at high Ca2+. Ca2+ also displaced C-terminal TnT from actin-tropomyosin but without movement toward TnC. Deletion of C-terminal TnT produced changes in TnI-143 like those effected by Ca2+, but effects on TnI-159 were muted; there was no effect on the distance of the switch region to TnC-84. Substituting Ala for basic residues within C-terminal TnT displaced C-terminal TnT from actin-tropomyosin. The results suggest that C-terminal TnT stabilizes tropomyosin in the inactive position on actin. Removal of basic residues from C-terminal TnT produced a Ca2+-like state except that the switch region of TnI was not bound to TnC. Addition of Ca2+ caused more extreme displacement from actin-tropomyosin as the active state became more fully occupied as in the case of wild-type TnT in the presence of both Ca2+ and bound rigor myosin S1.


Assuntos
Troponina I , Troponina T , Actinas/metabolismo , Cálcio/metabolismo , Humanos , Músculo Esquelético/metabolismo , Tropomiosina/química , Troponina C/química , Troponina C/genética , Troponina I/química , Troponina T/química , Troponina T/genética
6.
Psychiatr Psychol Law ; 29(6): 900-925, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36267603

RESUMO

Sex offender laws were designed to decrease sexual violence. The current mixed methods study examined attitudes and opinions of parole and probation officers who have supervised individuals convicted of sexual offenses (n = 361) regarding sex offender legislation and how these policies can be most effective in preventing recidivism. About half of the officers reported that registration and notification, sexually violent predator and Halloween laws were largely effective in preventing sexual victimization. Conversely, they perceived residence restriction laws and the tier system to be largely ineffective. A consistent theme that emerged from the qualitative responses was a movement away from blanket approaches towards a case-specific approach, tailoring the laws to individuals based upon their needs and risk level.

7.
Biochemistry ; 59(37): 3487-3497, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32840354

RESUMO

Calcium binding to troponin C (TnC) is insufficient for full activation of myosin ATPase activity by actin-tropomyosin-troponin. Previous attempts to investigate full activation utilized ATP-free myosin or chemically modified myosin to stabilize the active state of regulated actin. We utilized the Δ14-TnT and the A8V-TnC mutants to stabilize the activated state at saturating Ca2+ and to eliminate one of the inactive states at low Ca2+. The observed effects differed in solution studies and in the more ordered in vitro motility assay and in skinned cardiac muscle preparations. At saturating Ca2+, full activation with Δ14-TnT·A8V-TnC decreased the apparent KM for actin-activated ATPase activity compared to bare actin filaments. Rates of in vitro motility increased at both high and low Ca2+ with Δ14-TnT; the maximum shortening speed at high Ca2+ increased 1.8-fold. Cardiac muscle preparations exhibited increased Ca2+ sensitivity and large increases in resting force with either Δ14-TnT or Δ14-TnT·A8V-TnC. We also observed a significant increase in the maximal rate of tension redevelopment. The results of full activation with Ca2+ and Δ14-TnT·A8V-TnC confirmed and extended several earlier observations using other means of reaching full activation. Furthermore, at low Ca2+, elimination of the first inactive state led to partial activation. This work also confirms, in three distinct experimental systems, that troponin is able to stabilize the active state of actin-tropomyosin-troponin without the need for high-affinity myosin binding. The results are relevant to the reason for two inactive states and for the role of force producing myosin in regulation.


Assuntos
Actinas/metabolismo , Cálcio/metabolismo , Movimento Celular , Miocárdio/metabolismo , Tropomiosina/metabolismo , Troponina C/metabolismo , Troponina T/metabolismo , Adenosina Trifosfatases/metabolismo , Animais , Bovinos , Humanos , Miocárdio/citologia , Ligação Proteica , Troponina C/química , Troponina C/genética , Troponina T/química , Troponina T/genética
8.
J Biol Chem ; 294(51): 19535-19545, 2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31712308

RESUMO

Striated muscle is activated by myosin- and actin-linked processes, with the latter being regulated through changes in the position of tropomyosin relative to the actin surface. The C-terminal region of cardiac troponin T (TnT), a tropomyosin-associated protein, is required for full TnT inactivation at low Ca2+ and for limiting its activation at saturating Ca2+ Here, we investigated whether basic residues in this TnT region are involved in these activities, whether the TnT C terminus undergoes Ca2+-dependent conformational changes, and whether these residues affect cardiac muscle contraction. We generated a human cardiac TnT variant in which we replaced seven C-terminal Lys and Arg residues with Ala and added a Cys residue at either position 289 or 275 to affix a fluorescent probe. At pCa 3.7, actin filaments containing high-alanine TnT had an elevated ATPase rate like that obtained when the last TnT 14 residues were deleted. Acrylodan-tropomyosin fluorescence changes and S1-actin binding kinetics revealed that at pCa 8, the high-alanine TnT-containing filaments did not enter the first inactive state. FRET analyses indicated that the C-terminal TnT region approached Cys-190 of tropomyosin as actin filaments transitioned to the inactive B state; that transition was abolished with high-alanine TnT. High-alanine TnT-containing cardiac muscle preparations had increased Ca2+ sensitivity of both steady-state isometric force and sinusoidal stiffness as well as increased maximum steady-state isometric force and sinusoidal stiffness. We conclude that C-terminal basic residues in cardiac TnT are critical for the regulation of cardiac muscle contraction.


Assuntos
Citoesqueleto de Actina/química , Actinas/química , Cálcio/química , Troponina T/química , Troponina T/fisiologia , Adenosina Trifosfatases/química , Alanina/química , Animais , Arginina/química , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Humanos , Cinética , Lisina/química , Contração Muscular , Mutação , Miosinas/química , Ligação Proteica , Conformação Proteica , Domínios Proteicos , Coelhos , Estresse Mecânico , Suínos , Tropomiosina/química
9.
Psychol Med ; 50(15): 2566-2574, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31576782

RESUMO

BACKGROUND: Adolescence is a high-risk period for the onset of suicidal thoughts and behaviors. Identification of preceding patterns of internalizing and externalizing symptoms that are associated with subsequent suicidal thoughts may offer a better understanding of how to prevent adolescent suicide. METHODS: Data from the National Longitudinal Survey of Children and Youth, a prospective population-based Canadian cohort, contained Child Behavior Checklist items which were used to examine profiles and transitions of internalizing and externalizing symptoms in children, aged 6-11 years (n = 8266). The association between these profiles/transitions and suicidal thoughts in adolescents was examined using multivariate logistic regression modeling. RESULTS: Latent profile analyses identified four measurement invariant profiles of internalizing and externalizing symptoms at ages 6/7 and 10/11: (1) low on all symptoms, (2) moderate on all symptoms, (3) high on all symptoms, and (4) high on hyperactivity/inattention and internalizing. Recurrent (homotypic or heterotypic) and increasing symptoms from 6/7 to 10/11 were associated with suicidal thoughts in adolescence, compared to those with stable low symptoms. Those with decreasing symptoms from 6/7 to 10/11 were not at increased risk of suicidal thought in adolescence. CONCLUSIONS: While patterns of recurrent symptoms were associated with suicidal thoughts, a similar association was observed between profiles at age 10/11 years and suicidal thoughts. This suggests that the recent assessments of mental health symptoms in children may be as sufficient a predictor of adolescent suicidal thought as transition profiles.


Assuntos
Comportamento do Adolescente , Controle Interno-Externo , Ideação Suicida , Adolescente , Canadá , Criança , Depressão , Feminino , Humanos , Modelos Logísticos , Estudos Longitudinais , Masculino , Análise Multivariada , Estudos Prospectivos , Medição de Risco
10.
Biophys J ; 115(4): 702-712, 2018 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-30057009

RESUMO

Activation of striated muscle contraction occurs in response to Ca2+ binding to troponin C. The resulting reorganization of troponin repositions tropomyosin on actin and permits activation of myosin-catalyzed ATP hydrolysis. It now appears that the C-terminal 14 amino acids of cardiac troponin T (TnT) control the level of activity at both low and high Ca2+. We made a series of C-terminal truncation mutants of human cardiac troponin T, isoform 2, to determine if the same residues of TnT are involved in the low and high Ca2+ effects. We measured the effect of these mutations on the normalized ATPase activity at saturating Ca2+. Changes in acrylodan tropomyosin fluorescence and the degree of Ca2+ stimulation of the rate of binding of rigor myosin subfragment 1 to pyrene-labeled actin-tropomyosin-troponin were measured at low Ca2+. These measurements define the distribution of actin-tropomyosin-troponin among the three regulatory states. Residues SKTR and GRWK of TnT were required for the functioning of TnT at both low and high Ca2+. Thus, the effects on forming the inactive B-state and in retarding formation of the active M-state require the same regions of TnT. We also observed that the rate of binding of rigor subfragment 1 to pyrene-labeled regulated actin at saturating Ca2+ was higher for the truncation mutants than for wild-type TnT. This violated an assumption necessary for determining the B-state population by this kinetic method.


Assuntos
Cálcio/metabolismo , Miocárdio/metabolismo , Deleção de Sequência , Troponina T/genética , Troponina T/metabolismo , Actinas/metabolismo , Trifosfato de Adenosina/metabolismo , Humanos , Hidrólise , Contração Muscular , Tropomiosina/metabolismo , Troponina T/química
11.
Depress Anxiety ; 35(8): 700-716, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29878410

RESUMO

BACKGROUND: Adolescent depression may increase risk for poor mental health outcomes in adulthood. The objective of this study was to systematically review the literature on the association between adolescent depression and adult anxiety and depressive disorders as well as suicidality. METHODS: EMBASE, MEDLINE, and PSYCinfo databases were searched and longitudinal cohort studies in which depression was measured in adolescence (age 10-19) and outcomes of depressive disorders, anxiety disorders, or suicidality were measured in adulthood (age 21+), were selected. Meta-analysis using inverse variance and random effects modeling, along with sensitivity analyses, were used to synthesize article estimates. RESULTS: Twenty articles were identified, representing 15 unique cohorts. Seventeen of 18 articles showed adolescent depression increased risk for adult depression; eleven pooled cohorts estimated that adolescents with depression had 2.78 (1.97, 3.93) times increased odds of depression in adulthood. Seven of eight articles that investigated the association between adolescent depression and any adult anxiety found a significant association. Three of five articles showed a significant association between adolescent depression and adult suicidality. CONCLUSION: This review shows that adolescent depression increases the risk for subsequent depression later in life. Articles consistently found that adolescent depression increases the risk for anxiety disorders in adulthood, but evidence was mixed on whether or not a significant association existed between adolescent depression and suicidality in adulthood. Early intervention in adolescent depression may reduce long-term burden of disease.


Assuntos
Transtornos de Ansiedade/epidemiologia , Transtorno Depressivo/epidemiologia , Suicídio/estatística & dados numéricos , Adolescente , Adulto , Humanos
12.
Biochemistry ; 56(23): 2928-2937, 2017 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-28530094

RESUMO

Striated muscle contraction is regulated by the actin-associated proteins tropomyosin and troponin. The extent of activation of myosin ATPase activity is lowest in the absence of both Ca2+ and activating cross-bridges (i.e., S1-ADP or rigor S1). Binding of activating species of myosin to actin at a saturating Ca2+ concentration stabilizes the most active state (M state) of the actin-tropomyosin-troponin complex (regulated actin). Ca2+ binding alone produces partial stabilization of the active state. The extent of stabilization at a saturating Ca2+ concentration depends on the isoform of the troponin subunits, the phosphorylation state of troponin, and, in the case of cardiac muscle, the presence of hypertrophic cardiomyopathy-producing mutants of troponin T and troponin I. Cardiac dysfunction is also associated with mutations of troponin C (TnC). Troponin C mutants A8V, C84Y, and D145E increase the Ca2+ sensitivity of ATPase activity. We show that these mutants change the distribution of regulated actin states. The A8V and C84Y TnC mutants decreased the inactive B state distribution slightly at low Ca2+ concentrations, but the D145E mutants had no effect on that state. All TnC mutants increased the level of the active M state compared to that of the wild type, at a saturating Ca2+ concentration. Troponin complexes that contained two mutations that stabilize the active M state, A8V TnC and Δ14 TnT, appeared to be completely in the active state in the presence of only Ca2+. Because Ca2+ gives full activation, in this situation, troponin must be capable of positioning tropomyosin in the active M state without the need for rigor myosin binding.


Assuntos
Actinas/metabolismo , Deleção de Genes , Mutação , Tropomiosina/metabolismo , Troponina C/metabolismo , Troponina T/metabolismo , Actinas/química , Trifosfato de Adenosina/metabolismo , Substituição de Aminoácidos , Animais , Sinalização do Cálcio , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/metabolismo , Bovinos , Humanos , Cinética , Radioisótopos de Fósforo , Multimerização Proteica , Estabilidade Proteica , Coelhos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Tropomiosina/química , Troponina C/química , Troponina C/genética , Troponina T/química , Troponina T/genética
13.
Biochemistry ; 55(32): 4533-40, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27454189

RESUMO

The R146G mutation of troponin I (TnI) is associated with hypertrophic cardiomyopathy in humans. Earlier data pointed to stabilization of the intermediate, C state, of actin-tropomyosin-troponin by this mutant. Because cardiac disorders appear to be linked to changes in regulated actin distributions, we determined the extent to which the R146G TnI mutant alters the distribution of states at low and high Ca(2+) concentrations. We show, from measurements of the kcat for actin-activated ATPase activity at saturating Ca(2+) concentrations, that R146G TnI reduced the population of the active, M, state to 25% of the wild-type level. Together with acrylodan-tropomyosin fluorescence measurements of the B state, it appeared that the C state was populated at ∼91% of the total for the R146G TnI-containing actin filaments. The C state was also more heavily populated at low Ca(2+) concentrations. Acrylodan-tropomyosin fluorescence changes showed a large diminution in the inactive state value relative to the wild-type value without a comparable increase in the active state. Furthermore, the rate of binding of rigor S1 to pyrene-labeled actin filaments containing R146G TnI was faster than the rate of binding to wild-type filaments at low free Ca(2+) concentrations. These results indicate that the inhibitory region of TnI affects the B-C and M-C equilibria of actin-tropomyosin-troponin. The observation that a mutation in the inhibitory region affects the M-C equilibrium may point to a novel regulatory interaction.


Assuntos
Actinas/química , Actinas/metabolismo , Cálcio/farmacologia , Cardiomiopatias/genética , Mutação , Troponina I/genética , Animais , Cardiomiopatias/metabolismo , Bovinos , Relação Dose-Resposta a Droga , Cinética , Camundongos , Estabilidade Proteica , Coelhos
14.
J Immunother ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38764383

RESUMO

Fluorine-18 fluorodeoxygluocose positron emission tomography (FDG-PET) is increasingly used in the evaluation of response to immune checkpoint inhibitor (ICI) therapy. Incidental findings of increased vessel wall uptake may prompt the concern for ICI-induced large vessel vasculitis (LVV). Precise radiographic and clinical evaluation is required to determine if this represents true vasculitis, as use of immune suppression and ICI discontinuation can have significant impacts on patient outcomes. We performed a retrospective case analysis of 4 consecutive patients referred to 2 rheumatology clinics treated with ICI with incidental findings of LVV on FDG-PET, reviewing their clinical course and radiographic findings. All 4 cases had FDG-PET scans for routine oncology indications and had no associated clinical features of LVV. One patient was treated with corticosteroids and no patients developed any clinical evidence of vasculitis during a mean follow-up period of 17 months (range: 7-33 mo). All FDG-PET images reporting LVV underwent a standardized analysis to identify any technical issues or concerns with interpretation. In review of imaging, 3 of the cases may have been due to delayed tracer to scan interval leading to misinterpretation of vascular uptake as suspected LVV. Recognition of technical pitfalls in FDG-PET interpretation is crucial to inform the need for immunosuppression and the safety of continued ICI therapy.

15.
Viruses ; 16(3)2024 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-38543793

RESUMO

Single-dose, immunogenic DNA (iDNA) vaccines coding for whole live-attenuated viruses are reviewed. This platform, sometimes called immunization DNA, has been used for vaccine development for flavi- and alphaviruses. An iDNA vaccine uses plasmid DNA to launch live-attenuated virus vaccines in vitro or in vivo. When iDNA is injected into mammalian cells in vitro or in vivo, the RNA genome of an attenuated virus is transcribed, which starts replication of a defined, live-attenuated vaccine virus in cell culture or the cells of a vaccine recipient. In the latter case, an immune response to the live virus vaccine is elicited, which protects against the pathogenic virus. Unlike other nucleic acid vaccines, such as mRNA and standard DNA vaccines, iDNA vaccines elicit protection with a single dose, thus providing major improvement to epidemic preparedness. Still, iDNA vaccines retain the advantages of other nucleic acid vaccines. In summary, the iDNA platform combines the advantages of reverse genetics and DNA immunization with the high immunogenicity of live-attenuated vaccines, resulting in enhanced safety and immunogenicity. This vaccine platform has expanded the field of genetic DNA and RNA vaccines with a novel type of immunogenic DNA vaccines that encode entire live-attenuated viruses.


Assuntos
Flavivirus , Vacinas de DNA , Vacinas Virais , Animais , Anticorpos Antivirais , Flavivirus/genética , Vacinas Atenuadas , DNA , Mamíferos
16.
Viruses ; 16(4)2024 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-38675975

RESUMO

Lymphocytic choriomeningitis virus (LCMV) and Lassa virus (LASV) share many genetic and biological features including subtle differences between pathogenic and apathogenic strains. Despite remarkable genetic similarity, the viscerotropic WE strain of LCMV causes a fatal LASV fever-like hepatitis in non-human primates (NHPs) while the mouse-adapted Armstrong (ARM) strain of LCMV is deeply attenuated in NHPs and can vaccinate against LCMV-WE challenge. Here, we demonstrate that internalization of WE is more sensitive to the depletion of membrane cholesterol than ARM infection while ARM infection is more reliant on endosomal acidification. LCMV-ARM induces robust NF-κB and interferon response factor (IRF) activation while LCMV-WE seems to avoid early innate sensing and failed to induce strong NF-κB and IRF responses in dual-reporter monocyte and epithelial cells. Toll-like receptor 2 (TLR-2) signaling appears to play a critical role in NF-κB activation and the silencing of TLR-2 shuts down IL-6 production in ARM but not in WE-infected cells. Pathogenic LCMV-WE infection is poorly recognized in early endosomes and failed to induce TLR-2/Mal-dependent pro-inflammatory cytokines. Following infection, Interleukin-1 receptor-associated kinase 1 (IRAK-1) expression is diminished in LCMV-ARM- but not LCMV-WE-infected cells, which indicates it is likely involved in the LCMV-ARM NF-κB activation. By confocal microscopy, ARM and WE strains have similar intracellular trafficking although LCMV-ARM infection appears to coincide with greater co-localization of early endosome marker EEA1 with TLR-2. Both strains co-localize with Rab-7, a late endosome marker, but the interaction with LCMV-WE seems to be more prolonged. These findings suggest that LCMV-ARM's intracellular trafficking pathway may facilitate interaction with innate immune sensors, which promotes the induction of effective innate and adaptive immune responses.


Assuntos
Imunidade Inata , Vírus da Coriomeningite Linfocítica , Internalização do Vírus , Vírus da Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/patogenicidade , Vírus da Coriomeningite Linfocítica/fisiologia , Animais , Humanos , Camundongos , Receptor 2 Toll-Like/metabolismo , Receptor 2 Toll-Like/genética , Endossomos/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Linhagem Celular , Coriomeningite Linfocítica/imunologia , Coriomeningite Linfocítica/virologia , Células Epiteliais/virologia , Células Epiteliais/imunologia
17.
Child Abuse Negl ; : 106554, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37993365

RESUMO

BACKGROUND: The COVID-19 pandemic has created significant disruptions, with parents of school-age children being identified as a vulnerable population. Limited research has longitudinally tracked the mental health trajectories of parents over the active pandemic period. In addition, parents' history of adverse (ACEs) and benevolent (BCEs) childhood experiences may compound or attenuate the effect of COVID-19 stressors on parental psychopathology. OBJECTIVE: To identify distinct longitudinal trajectories of parental mental health over the COVID-19 pandemic and how these trajectories are associated with parental ACEs, BCEs, and COVID-19 stress. PARTICIPANTS AND SETTING: 547 parents of 5-18-year-old children from the U.K., U.S., Canada, and Australia. METHODS: Growth mixture modelling was used to identify trajectories of parental mental health (distress, anxiety, post-traumatic stress, and substance use) from May 2020 to October 2021. COVID-19 stress, ACEs, and BCEs were assessed as predictors of mental health trajectories via multinomial logistic regression. RESULTS: Two-class trajectories of "Low Stable" and "Moderate Stable" symptoms were identified for psychological distress and anxiety. Three-class trajectories of "Low Stable", "High Stable", and "High Decreasing" symptoms were observed for post-traumatic stress. Reliable trajectories for substance use could not be identified. Multinomial logistic regression showed that COVID-19 stress and ACEs independently predicted membership in trajectories of greater mental health impairment, while BCEs independently predicted membership in trajectories of lower psychological distress. CONCLUSIONS: Parents experienced mostly stable mental health symptomatology, with trajectories varying by overall symptom severity. COVID-19 stress, ACEs, and BCEs each appear to play a role in parents' mental health during this unique historical period.

18.
Psychoneuroendocrinology ; 147: 105969, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36335755

RESUMO

Pregnancy and the early postpartum signify a period of high stress. Perinatal stress can include psychological distress (PD), such as anxiety, depression, and stress, as well as neuroendocrine stress, indexed by activation of the hypothalamic-pituitary-adrenal (HPA) axis and the production of the hormone cortisol. Elevated PD and cortisol levels during the perinatal period can have long-term implications for the mother and child. Methodological advances have enabled the sampling of cortisol from hair, to provide a retrospective marker of HPA axis activity over several months. Despite knowing that maternal PD and HPA activity during the perinatal period independently impact health and development, research to date is unclear as to the association between maternal PD and hair cortisol. The present meta-analysis included 29 studies to assess the strength of the relation between maternal PD and hair cortisol levels during pregnancy and the early postpartum period. Several sample and methodological factors were assessed as moderators of this effect. Analyses were conducted using multilevel meta-analysis. Results of the multilevel meta-analysis indicated that the overall effect size between PD and HCC was small but not significant z = 0.039, 95% CI [- 0.001, 0.079]. Moderator analyses indicated that the strength of the association between PD and hair cortisol was moderated by pregnancy status (i.e., effects were stronger in pregnant compared to postpartum samples), timing of HCC and PD measurements (i.e., effects were larger when PD was measured before HCC) and geographic location (i.e., effects were larger in North American studies). The findings advance our understanding of the link between PD and HPA activity during the perinatal period, a time of critical impact to child development.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Angústia Psicológica , Feminino , Criança , Gravidez , Humanos , Hidrocortisona/análise , Sistema Hipotálamo-Hipofisário/química , Sistema Hipófise-Suprarrenal/química , Estudos Retrospectivos , Estresse Psicológico , Cabelo/química , Período Pós-Parto/psicologia , Parto
19.
Antiviral Res ; 209: 105492, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36535309

RESUMO

Molnupiravir (EIDD-2801) is a prodrug of a ribonucleoside analogue that is currently being used under a US FDA emergency use authorization for the treatment of mild to moderate COVID-19. We evaluated molnupiravir for efficacy as an oral treatment in the rhesus macaque model of SARS-CoV-2 infection. Twenty non-human primates (NHPs) were challenged with SARS-CoV-2 and treated with 75 mg/kg (n = 8) or 250 mg/kg (n = 8) of molnupiravir twice daily by oral gavage for 7 days. The NHPs were observed for 14 days post-challenge and monitored for clinical signs of disease. After challenge, all groups showed a trend toward increased respiration rates. Treatment with molnupiravir significantly reduced viral RNA levels in bronchoalveolar lavage (BAL) samples at Days 7 and 10. Considering the mild to moderate nature of SARS-CoV-2 infection in the rhesus macaque model, this study highlights the importance of monitoring the viral load in the lung as an indicator of pharmaceutical efficacy for COVID-19 treatments. Additionally, this study provides evidence of the efficacy of molnupiravir which supplements the current ongoing clinical trials of this drug.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Macaca mulatta , Citidina/farmacologia , Citidina/uso terapêutico
20.
JCI Insight ; 8(22)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37824216

RESUMO

Aberrant fibroblast function plays a key role in the pathogenesis of idiopathic pulmonary fibrosis, a devastating disease of unrelenting extracellular matrix deposition in response to lung injury. Platelet-derived growth factor α-positive (Pdgfra+) lipofibroblasts (LipoFBs) are essential for lung injury response and maintenance of a functional alveolar stem cell niche. Little is known about the effects of lung injury on LipoFB function. Here, we used single-cell RNA-Seq (scRNA-Seq) technology and PdgfraGFP lineage tracing to generate a transcriptomic profile of Pdgfra+ fibroblasts in normal and injured mouse lungs 14 days after bleomycin exposure, generating 11 unique transcriptomic clusters that segregated according to treatment. While normal and injured LipoFBs shared a common gene signature, injured LipoFBs acquired fibrogenic pathway activity with an attenuation of lipogenic pathways. In a 3D organoid model, injured Pdgfra+ fibroblast-supported organoids were morphologically distinct from those cultured with normal fibroblasts, and scRNA-Seq analysis suggested distinct transcriptomic changes in alveolar epithelia supported by injured Pdgfra+ fibroblasts. In summary, while LipoFBs in injured lung have not migrated from their niche and retain their lipogenic identity, they acquire a potentially reversible fibrogenic profile, which may alter the kinetics of epithelial regeneration and potentially contribute to dysregulated repair, leading to fibrosis.


Assuntos
Fibrose Pulmonar Idiopática , Lesão Pulmonar , Animais , Camundongos , Fibroblastos/metabolismo , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/patologia , Lesão Pulmonar/patologia , Receptores Proteína Tirosina Quinases/metabolismo
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