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1.
Nurs Educ Perspect ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856643

RESUMO

ABSTRACT: The purpose of this project was to determine if physician participation in simulation affects students' perceptions of nurse/physician communication and collaboration. Fifty-five students participated in six groups. Three groups had a physician present and involved during their eight-hour pediatric simulation; the others continued with current practice, which involved phone contact with an individual posing as a physician. There was a statistically significant difference in two items on the Nurse Attitudes About Communicating and Collaborating With Physicians tool when pre- and post-simulation means were compared. Findings are consistent with previous research, indicating simulation-based learning can improve students' perceptions of nurse-physician collaboration.

2.
SAGE Open Nurs ; 9: 23779608231186059, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37425289

RESUMO

Introduction: Effective communication is an essential skill for the professional nurse. Previous research demonstrates that nursing students lack skills in written communication, and there is limited time in the nursing curriculum to provide needed instruction. To address this issue, a writing workshop was provided for students at a regional state university. Methods: Nursing faculty developed and led four identical in-person sessions of the workshop over the course of one semester. Before and after each workshop, students completed the same quantitative survey. Results: Data indicate that students' knowledge and confidence of American Psychological Association (APA) format increased significantly as a result of the workshop. Conclusion: A workshop approach is a useful strategy to address the writing needs of nursing students.

3.
Ther Adv Med Oncol ; 15: 17588359221146133, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36643653

RESUMO

Background: The single-arm phase II APT trial established trastuzumab and paclitaxel (TH) as the standard adjuvant regimen for small human epidermal growth factor receptor 2 (HER2+) tumors. However, paclitaxel causes alopecia and has high rates of neuropathy and hypersensitivity reactions. In patients with metastatic HER2+ breast cancer (BC), the combination of trastuzumab and vinorelbine (TV) is effective and well tolerated. There is a need for alternative non-anthracycline/taxane-based regimens for patients with HER2+ early-stage BC, especially for those with contraindications or who wish to avoid side effects of taxane-based regimens. Here we describe our institutional experience with adjuvant TV for patients with early-stage HER2+ BC. Methods: Clinicopathological characteristics, treatment details, and outcomes of patients with localized HER2+ BC treated with adjuvant TV from 2007 to 2021 at a large academic medical institution were collected. Study endpoints included invasive disease-free survival (IDFS), overall survival (OS), and safety/tolerability. IDFS and OS were measured from start date of TV treatment to date of event/last follow-up and date of death/last follow-up, respectively. Results: A total of 30 patients were treated with TV. All patients received trastuzumab at standard dosing and vinorelbine at a starting dose of 25 mg/m2 either on days 1/8 or on days 1/8/21 (weekly) of a 21-day cycle with four planned cycles. Median age at diagnosis was 59 years (range: 36-81). 90.3% of patients had anatomic pathologic stage IA BC and 9.7% stage IIA BC. Of the 30 patients, 24 of them opted to pursue TV due to concerns related to alopecia, neuropathy, and other toxicities, and 6 switched from treatment with TH to TV due to toxicities. Eight patients experienced neutropenia with no cases of febrile neutropenia. No patients experienced alopecia or long-term neuropathy. With a median follow-up of 68 months (5.7 years), the 5-year IDFS rate was 90.9%, with one local and one distant recurrence. The 5-year OS was 100%. Conclusions: Trastuzumab in combination with vinorelbine in the adjuvant, early-stage setting for low-risk HER2+ BC demonstrated clinical efficacy and appeared to be well tolerated. TV warrants further evaluation as an alternative regimen to TH for patients with early-stage HER2+ BC.

4.
Ther Adv Med Oncol ; 14: 17588359221119370, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36051470

RESUMO

Purpose: To explore the immunogenicity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines in patients with breast cancer based on type of anticancer treatment. Methods: Patients with breast cancer had anti-spike antibody concentrations measured ⩾14 days after receiving a full SARS-CoV-2 vaccination series. The primary endpoint was IgA/G/M anti-spike antibody concentration. Multiple regression analysis was used to analyze log10-transformed antibody titer concentrations. Results: Between 29 April and 20 July 2021, 233 patients with breast cancer were enrolled, of whom 212 were eligible for the current analysis. Patients who received mRNA-1273 (Moderna) had the highest antibody concentrations [geometric mean concentration (GMC) in log10: 3.0 U/mL], compared to patients who received BNT162b2 (Pfizer) (GMC: 2.6 U/mL) (multiple regression adjusted p = 0.013) and Ad26.COV2.S (Johnson & Johnson/Janssen) (GMC: 2.6 U/mL) (p = 0.071). Patients receiving cytotoxic therapy had a significantly lower antibody titer GMC (2.5 U/mL) compared to patients on no therapy or endocrine therapy alone (3.0 U/mL) (p = 0.005). Patients on targeted therapies (GMC: 2.7 U/mL) also had a numerically lower GMC compared to patients not receiving therapy/on endocrine therapy alone, although this result was not significant (p = 0.364). Among patients who received an additional dose of vaccine (n = 31), 28 demonstrated an increased antibody response that ranged from 0.2 to >4.4 U/ mL. Conclusion: Most patients with breast cancer generate detectable anti-spike antibodies following SARS-CoV-2 vaccination, though systemic treatments and vaccine type impact level of response. Further studies are needed to better understand the clinical implications of different antibody levels, the effectiveness of additional SARS-CoV-2 vaccine doses, and the risk of breakthrough infections among patients with breast cancer.

5.
Oncologist ; 26(10): 827-834, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34176192

RESUMO

Patients with metastatic triple-negative breast cancer have a poor prognosis. Sacituzumab govitecan (IMMU-132) is an antibody-drug conjugate that contains the irinotecan active metabolite, SN-38, linked to a humanized monoclonal antibody targeting trophoblast cell surface antigen 2, which is overexpressed in many solid tumors. In a basket design phase I/II study, sacituzumab govitecan demonstrated promising single-agent therapeutic activity in multiple cancer cohorts, leading to accelerated approval by the U.S. Food and Drug Administration of sacituzumab govitecan-hziy (TRODELVY) for the treatment of patients with metastatic triple-negative breast cancer who had received at least two prior therapies in the metastatic setting. Recently, results of the phase III trial, ASCENT, were confirmatory. There is limited available information on the adverse event management with sacituzumab govitecan needed to maximize the dose and duration of effective therapy while maintaining patient quality of life. This review summarizes the clinical development and the practical management of patients receiving sacituzumab govitecan. Sacituzumab govitecan has a well-defined and manageable toxicity profile, and rapid recognition and appropriate early and proactive management will allow clinicians to optimize sacituzumab govitecan treatment for patients. IMPLICATIONS FOR PRACTICE: Sacituzumab govitecan (TRODELVY) is a novel antibody-drug conjugate composed of the active metabolite of irinotecan (SN-38) conjugated to a monoclonal antibody targeting trophoblast cell surface antigen 2, an epithelial cell surface antigen overexpressed in many cancers. Because of the rapid approval of sacituzumab govitecan, there is limited available information on adverse event (AE) management with this agent. As such, this article reviews the clinical development of the drug, the AE profile, and provides recommendations regarding AE management to help optimize therapy with sacituzumab govitecan.


Assuntos
Imunoconjugados , Neoplasias de Mama Triplo Negativas , Anticorpos Monoclonais Humanizados , Camptotecina/análogos & derivados , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Humanos , Imunoconjugados/efeitos adversos , Qualidade de Vida , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
6.
J Oncol Pharm Pract ; 26(4): 912-917, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31631811

RESUMO

BACKGROUND: Although landmark trials in the metastatic (CLEOPATRA) and neo-adjuvant (NeoSphere; TRYPHAENA) settings identified all-grade diarrhea as a pertuzumab-associated adverse event, it was not classified as dose-limiting. In actual practice, diarrhea is often a reason for treatment modifications. OBJECTIVES: To compare the risk of pertuzumab-associated diarrhea in actual practice to the risks in randomized controlled trials. METHODS: We conducted a retrospective cohort study of HER2/neu-positive breast cancer patients who received a pertuzumab-containing regimen between January 2012 and August 2015. We calculated the risk of diarrhea with 95% confidence limits (CLs), and then used two-sample t-tests to compare the risk between trials and actual practice. RESULTS: A total of 27 patients in the study cohort received a pertuzumab-containing treatment regimen for HER2/neu-positive breast cancer. The overall risk of all-grade and severe diarrhea in actual practice was 70% (95% CLs 55-90%) and 37% (95% CLs 20-66%), respectively. No severe diarrhea was observed in the metastatic setting, and the risk of all-grade diarrhea (44%, 95% CLs 21-92%) was similar to the CLEOPATRA study (67%). The risk of all-grade diarrhea in the neo-adjuvant setting was 83% (95% CLs 68-100%), compared to 46% in the NeoSphere trial (p = 0.03). The risk of severe diarrhea (Grade 3-4) in the neo-adjuvant setting was 47% (95% CLs 27-80%) versus 6% in the NeoSphere (p < 0.0001) and 12% in the TRYPHAENA (p < 0.01) trials. CONCLUSIONS: The risk of all-grade and severe diarrhea associated with neoadjuvant pertuzumab use for HER2/neu-positive breast cancer was greater in actual practice than in trials.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Diarreia/induzido quimicamente , Adulto , Ensaios Clínicos como Assunto , Feminino , Humanos , Pessoa de Meia-Idade , Receptor ErbB-2/análise , Estudos Retrospectivos
7.
PLoS One ; 11(5): e0154785, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27144448

RESUMO

During progeny assembly, viruses selectively package virion genomes from a nucleic acid pool that includes host nucleic acids. For large dsDNA viruses, including tailed bacteriophages and herpesviruses, immature viral DNA is recognized and translocated into a preformed icosahedral shell, the prohead. Recognition involves specific interactions between the viral packaging enzyme, terminase, and viral DNA recognition sites. Generally, viral DNA is recognized by terminase's small subunit (TerS). The large terminase subunit (TerL) contains translocation ATPase and endonuclease domains. In phage lambda, TerS binds a sequence repeated three times in cosB, the recognition site. TerS binding to cosB positions TerL to cut the concatemeric DNA at the adjacent nicking site, cosN. TerL introduces staggered nicks in cosN, generating twelve bp cohesive ends. Terminase separates the cohesive ends and remains bound to the cosB-containing end, in a nucleoprotein structure called Complex I. Complex I docks on the prohead's portal vertex and translocation ensues. DNA topology plays a role in the TerSλ-cosBλ interaction. Here we show that a site, I2, located between cosN and cosB, is critically important for an early DNA packaging step. I2 contains a complex static bend. I2 mutations block DNA packaging. I2 mutant DNA is cut by terminase at cosN in vitro, but in vivo, no cos cleavage is detected, nor is there evidence for Complex I. Models for what packaging step might be blocked by I2 mutations are presented.


Assuntos
Empacotamento do DNA/genética , DNA Viral/genética , Montagem de Vírus/genética , Adenosina Trifosfatases/metabolismo , Bacteriófago lambda/genética , Sequência de Bases , Sítios de Ligação , Vírus de DNA/genética , Endodesoxirribonucleases/metabolismo
8.
J Extra Corpor Technol ; 46(1): 53-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24779119

RESUMO

In an effort to provide optimal patient care, perfusionists should rely on information provided by current research. Present statistics, however, document a substantial underuse of evidence-based clinical practice and therapies not only in perfusion, but throughout the entire medical field. This investigation applied a statistical method--binomial proportion analysis--to aid in uncovering the trends in perfusion practice from 2004 to 2011. Through the analysis of national adult perfusion practice surveys, the feasibility of using binomial proportion statistical analysis is assessed in its ability to track adult perfusion practice proportional differentials over time and evaluate the adoption and attitudes toward the compliance of evidence-based practice within the field of perfusion. Surveys conducted in 2004 and 2006 on adult perfusion practice in the United States--although not published--are compared with data obtained by a similar survey distributed in 2011 through an international perfusion network system and perfusion mailing system, Perflist and Perfmail. The increase of perfusionists who practice retrograde and antegrade autologous priming (R/A AP) seen from 2004 to 2006 (35-50%) was statistically significant (Z(cal) = -2.30, p < .05) and from 2006 to 2011 (Z(calc) = -5.23; p < .05). Although the increase in biocompatible circuit (BC) use by perfusionists from 2004-2006 (53-64%) was not statistically significant (Z(calc) = -1.69, p < .05), the use of BCs did continue to increase (86%) significantly from 2006 to 2011 (Z(calc) = -9.15, p < .05). Other trends were observed; however, statistical significance was variable. This investigation demonstrates that binomial proportion statistical analysis is an effective method of evaluating perfusion practice trends and adoptions based on increasing or decreasing perfusion population proportion compliance over time.


Assuntos
Ponte Cardiopulmonar/estatística & dados numéricos , Ponte Cardiopulmonar/normas , Medicina Baseada em Evidências , Fidelidade a Diretrizes/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Padrões de Prática Médica/normas , Adulto , Ponte Cardiopulmonar/tendências , Feminino , Humanos , Masculino , Padrões de Prática Médica/tendências , Estados Unidos/epidemiologia
9.
J Immunol ; 187(7): 3785-97, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21908739

RESUMO

The HIV-1 broadly neutralizing Ab (bnAb) 2F5 has been shown to be poly-/self-reactive in vitro, and we previously demonstrated that targeted expression of its VDJ rearrangement alone was sufficient to trigger a profound B cell developmental blockade in 2F5 V(H) knockin (KI) mice, consistent with central deletion of 2F5 H chain-expressing B cells. In this study, we generate a strain expressing the entire 2F5 bnAb specificity, 2F5 V(H) × V(L) KI mice, and find an even higher degree of tolerance control than observed in the 2F5 V(H) KI strain. Although B cell development was severely impaired in 2F5 V(H) × V(L) KI animals, we demonstrate rescue of their B cells when cultured in IL-7/BAFF. Intriguingly, even under these conditions, most rescued B cell hybridomas produced mAbs that lacked HIV-1 Envelope (Env) reactivity due to editing of the 2F5 L chain, and the majority of rescued B cells retained an anergic phenotype. Thus, when clonal deletion is circumvented, κ editing and anergy are additional safeguards preventing 2F5 V(H)/V(L) expression by immature/transitional B cells. Importantly, 7% of rescued B cells retained 2F5 V(H)/V(L) expression and secreted Env-specific mAbs with HIV-1-neutralizing activity. This partial rescue was further corroborated in vivo, as reflected by the anergic phenotype of most rescued B cells in 2F5 V(H) × V(L) KI × Eµ-Bcl-2 transgenic mice and significant (yet modest) enrichment of Env-specific B cells and serum Igs. The rescued 2F5 mAb-producing B cell clones in this study are the first examples, to our knowledge, of in vivo-derived bone marrow precursors specifying HIV-1 bnAbs and provide a starting point for design of strategies aimed at rescuing such B cells.


Assuntos
Anticorpos Neutralizantes/imunologia , Linfócitos B/imunologia , Infecções por HIV/imunologia , Tolerância Imunológica/imunologia , Animais , Separação Celular , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Técnicas de Introdução de Genes , Genes de Imunoglobulinas/genética , Genes de Imunoglobulinas/imunologia , HIV-1/imunologia , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
10.
PLoS One ; 4(10): e7215, 2009 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-19806186

RESUMO

The membrane proximal external region (MPER) of HIV-1 gp41 has several features that make it an attractive antibody-based vaccine target, but eliciting an effective gp41 MPER-specific protective antibody response remains elusive. One fundamental issue is whether the failure to make gp41 MPER-specific broadly neutralizing antibodies like 2F5 and 4E10 is due to structural constraints with the gp41 MPER, or alternatively, if gp41 MPER epitope-specific B cells are lost to immunological tolerance. An equally important question is how B cells interact with, and respond to, the gp41 MPER epitope, including whether they engage this epitope in a non-canonical manner i.e., by non-paratopic recognition via B cell receptors (BCR). To begin understanding how B cells engage the gp41 MPER, we characterized B cell-gp41 MPER interactions in BALB/c and C57BL/6 mice. Surprisingly, we found that a significant (approximately 7%) fraction of splenic B cells from BALB/c, but not C57BL/6 mice, bound the gp41 MPER via their BCRs. This strain-specific binding was concentrated in IgM(hi) subsets, including marginal zone and peritoneal B1 B cells, and correlated with enriched fractions (approximately 15%) of gp41 MPER-specific IgM secreted by in vitro-activated splenic B cells. Analysis of Igh(a) (BALB/c) and Igh(b) (C57BL/6) congenic mice demonstrated that gp41 MPER binding was controlled by determinants of the Igh(a) locus. Mapping of MPER gp41 interactions with IgM(a) identified MPER residues distinct from those to which mAb 2F5 binds and demonstrated the requirement of Fc C(H) regions. Importantly, gp41 MPER ligation produced detectable BCR-proximal signaling events, suggesting that interactions between gp41 MPER and IgM(a) determinants may elicit partial B cell activation. These data suggest that low avidity, non-paratopic interactions between the gp41 MPER and membrane Ig on naïve B cells may interfere with or divert bnAb responses.


Assuntos
Receptor do Fator Ativador de Células B/metabolismo , Linfócitos B/virologia , Antígenos CD79/metabolismo , Membrana Celular/metabolismo , Proteína gp41 do Envelope de HIV/metabolismo , HIV-1/metabolismo , Animais , Epitopos/química , Feminino , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ligação Proteica , Transdução de Sinais , Baço/metabolismo
11.
Genetics ; 181(3): 1065-76, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19064709

RESUMO

Genetic background effects contribute to the phenotypic consequences of mutations and are pervasive across all domains of life that have been examined, yet little is known about how they modify genetic systems. In part this is due to the lack of tractable model systems that have been explicitly developed to study the genetic and evolutionary consequences of background effects. In this study we demonstrate that phenotypic expressivity of the scalloped(E3) (sd(E3)) mutation of Drosophila melanogaster is background dependent and is the result of at least one major modifier segregating between two standard lab wild-type strains. We provide evidence that at least one of the modifiers is linked to the vestigial region and demonstrate that the background effects modify the spatial distribution of known sd target genes in a genotype-dependent manner. In addition, microarrays were used to examine the consequences of genetic background effects on the global transcriptome. Expression differences between wild-type strains were found to be as large as or larger than the effects of mutations with substantial phenotypic effects, and expression differences between wild type and mutant varied significantly between genetic backgrounds. Significantly, we demonstrate that the epistatic interaction between sd(E3) and an optomotor blind mutation is background dependent. The results are discussed within the context of developing a complex but more realistic view of the consequences of genetic background effects with respect to mutational analysis and studies of epistasis and cryptic genetic variation segregating in natural populations.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/genética , Regulação da Expressão Gênica , Genoma de Inseto/genética , Mutação , Fatores de Transcrição/genética , Asas de Animais/metabolismo , Animais , Drosophila melanogaster/citologia , Drosophila melanogaster/metabolismo , Epistasia Genética , Ligação Genética , Variação Genética , Genômica , Dados de Sequência Molecular , Proteínas Nucleares/genética , Análise de Sequência com Séries de Oligonucleotídeos , Transcrição Gênica
12.
J Virol ; 82(6): 2821-35, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18184710

RESUMO

Varicella-zoster virus (VZV) is renowned for its very low titer when grown in cultured cells. There remains no single explanation for the low infectivity. In this study, viral particles on the surfaces of infected cells were examined by several imaging technologies. Few surface particles were detected at 48 h postinfection (hpi), but numerous particles were observed at 72 and 96 hpi. At 72 hpi, 75% of the particles resembled light (L) particles, i.e., envelopes without capsids. By 96 hpi, 85% of all particles resembled L particles. Subsequently, the envelopes of complete virions and L particles were investigated to determine their glycoprotein constituents. Glycoproteins gE, gI, and gB were detected in the envelopes of both types of particles in similar numbers; i.e., there appeared to be no difference in the glycoprotein content of the L particles. The viral particles emerged onto the cell surface amid actin-based filopodia, which were present in abundance within viral highways. Viral particles were easily detected at the base of and along the exterior surfaces of the filopodia. VZV particles were not detected within filopodia. In short, these results demonstrate that VZV infection of cultured cells produces a larger proportion of aberrant coreless particles than has been seen with any other previously examined alphaherpesvirus. Further, these results suggested a major disassociation between capsid formation and envelopment as an explanation for the invariably low VZV titer in cultured cells.


Assuntos
Herpesvirus Humano 3/fisiologia , Luz , Pseudópodes/virologia , Linhagem Celular , Glicoproteínas/fisiologia , Herpesvirus Humano 3/crescimento & desenvolvimento , Humanos , Microscopia Eletrônica , Proteínas do Envelope Viral/fisiologia
13.
Dev Biol ; 309(1): 56-69, 2007 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-17643406

RESUMO

Though initially identified as necessary for neural migration, Disconnected and its partially redundant paralog, Disco-related, are required for proper head segment identity during Drosophila embryogenesis. Here, we present evidence that these genes are also required for proper ventral appendage development during development of the adult fly, where they specify medial to distal appendage development. Cells lacking the disco genes cannot contribute to the medial and distal portions of ventral appendages. Further, ectopic disco transforms dorsal appendages toward ventral fates; in wing discs, the medial and distal leg development pathways are activated. Interestingly, this appendage role is conserved in the red flour beetle, Tribolium (where legs develop during embryogenesis), yet in the beetle we found no evidence for a head segmentation role. The lack of an embryonic head specification role in Tribolium could be interpreted as a loss of the head segmentation function in Tribolium or gain of this function during evolution of flies. However, we suggest an alternative explanation. We propose that the disco genes always function as appendage factors, but their appendage nature is masked during Drosophila embryogenesis due to the reduction of limb fields in the maggot style Drosophila larva.


Assuntos
Evolução Biológica , Padronização Corporal , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/metabolismo , Fatores de Transcrição/metabolismo , Tribolium/metabolismo , Animais , Drosophila/embriologia , Drosophila/crescimento & desenvolvimento , Cabeça/embriologia , Cabeça/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/metabolismo , Tribolium/embriologia , Tribolium/crescimento & desenvolvimento
14.
J Virol ; 80(19): 9544-56, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16973558

RESUMO

In the course of examining the trafficking pathways of varicella-zoster virus (VZV) glycoproteins gE, gI, gH, and gB, we discovered that all four are synthesized within 4 to 6 h postinfection (hpi) in cultured cells. Thereafter, they travel via the trans-Golgi network to the outer cell membrane. When we carried out a similar analysis on VZV gC, we observed little gC biosynthesis in the first 72 hpi. Further examination disclosed that gC was present in the inocula of infected cells, but no new gC biosynthesis occurred during the first 24 to 48 h thereafter, during which time new synthesis of gE, gH, and major capsid protein was easily detectable. Similarly, delayed gC biosynthesis was confirmed with three different VZV strains and two different cell lines. Bioinformatics analyses disclosed the presence of PBX/HOX consensus binding domains in the promoter/enhancer regions of the genes for VZV gC and ORF4 protein (whose orthologs transactivate gC in other herpesviruses). Bioinformatics analysis also identified two HOXA9 activation regions on ORF4 protein. Treatment of infected cultures with chemicals known to induce the production of PBX/HOX transcription proteins, namely, hexamethylene bisacetamide (HMBA) and retinoic acid, led to more rapid gC biosynthesis. Immunoblotting demonstrated a fivefold increase in the HOXA9 protein after HMBA treatment. In summary, these results documented that gC was not produced during early VZV replication cycles, presumably related to a deficiency in the PBX/HOX transcription factors. Furthermore, these results explain the apparent spontaneous loss of VZV gC in some passaged viruses, as well as other anomalous gC results.


Assuntos
Acetamidas/farmacologia , Herpesvirus Humano 3/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Tretinoína/farmacologia , Regulação para Cima/efeitos dos fármacos , Proteínas do Envelope Viral/metabolismo , Linhagem Celular , Células Gigantes/metabolismo , Herpesvirus Humano 3/genética , Herpesvirus Humano 3/ultraestrutura , Humanos , Microscopia Eletrônica de Varredura , Fases de Leitura Aberta/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica , Fatores de Transcrição/metabolismo , Proteínas do Envelope Viral/genética
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