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1.
BMC Infect Dis ; 23(1): 465, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37438705

RESUMO

BACKGROUND: Corneal transplants are the most common type of transplant and increasing in frequency. Donor cornea tissues are a rare source of herpes simplex virus (HSV) transmission and not routinely tested for presence of HSV. Donor graft-to-recipient transmission typically causes graft failure and anterior uveitis, and extra-ocular HSV disease has not been previously reported. We present a case of HSV transmission from donor cornea tissue that nearly cost the corneal transplant recipient his life. CASE REPORT: An elderly immunocompetent man developed an acute illness 10 days after having donor corneal tissue implanted in a Descemet membrane endothelial keratoplasty (DMEK). He was found to have HSV necrotizing hepatitis per liver biopsy, trilineage cytopenia, rhabdomyolysis, acute kidney failure, altered mental status, early-stage hemophagocytic lymphohistiocytosis (HLH), and donor corneal tissue implant infection resulting in graft failure and anterior uveitis. HSV DNA was detected in cerebral spinal fluid, peripheral blood, explanted donor corneal tissue, and anterior chamber fluid (220 million HSV DNA copies per mL). HSV-1 seroconversion denoted a primary HSV infection, and the patient had no other risk factor for HSV acquisition. Early recognition of HSV dissemination prompting treatment with intravenous acyclovir, as well as a short course of HLH-directed therapy, resolved the systemic illness. Vision was restored to near normal by replacement of the infected corneal graft with new donor DMEK tissue in conjunction with intravitreal foscarnet treatment. CONCLUSION: Awareness of the potential risk of donor cornea tissue transmitting HSV and leading to life-threatening HSV disease is paramount to early diagnosis and treatment. The role of donor cornea tissue in HSV transmission and disease merits additional attention and investigation.


Assuntos
Transplante de Córnea , Hepatite A , Hepatite , Herpes Simples , Herpesvirus Humano 1 , Idoso , Masculino , Humanos , Lâmina Limitante Posterior , Transplante de Córnea/efeitos adversos , Herpes Simples/diagnóstico
2.
Case Rep Infect Dis ; 2022: 7949471, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35847599

RESUMO

Background: Primary cytomegalovirus (CMV) infection of the immunocompetent host usually produces little-to-no illness. Occasionally, the infection results in mononucleosis syndrome, protracted fever, hepatitis, tissue-invasive disease, or Guillain-Barré syndrome. Hemolytic anemia and hemophagocytic lymphohistiocytosis (HLH) are rare complications that have not been reported to co-occur. Having hemolytic anemia in conjunction with more common findings of fever and hepatitis complicates the diagnosis of HLH. Case Presentation. A 34-year-old male with previously good health presented with a prolonged febrile illness, jaundice, and anemia. An extensive work-up during hospitalization revealed intravascular hemolytic anemia, leukopenia, hepatosplenomegaly, and biopsy evidence of extensive lymphohistiocytic infiltration of the liver with microgranulomata and sinusoidal hemophagocytosis. Soluble CD25 level was mildly elevated at 1200.3 pg/mL and the HScore calculation (fever, bicytopenia, hepatosplenomegaly, aspartate aminotransaminase 99 IU/L, ferritin 1570 ng/mL, fibrinogen 488 mg/dL, and triglycerides 173 mg/dL) suggested a moderate probability of reactive HLH. Primary CMV infection was diagnosed based on CMV IgM positivity, low CMV IgG avidity index, and low-grade CMV DNAemia. The CMV antigen was not detected in the liver biopsy, and the bone marrow biopsy was unremarkable. The illness began to improve before he received oral valganciclovir for 5 days, and he was in good health 10 months later. Conclusion: Acute CMV illness in an immunocompetent adult can present with hemolytic anemia and clinicopathologic abnormalities consistent with a form fruste of HLH. The illness is likely due to an excessive or unbalanced immune response that may self-correct.

3.
Pharmacol Res Perspect ; 9(6): e00882, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34747573

RESUMO

Zinc protoporphyrin (ZnPP), a naturally occurring metalloprotoporphyrin (MPP), is currently under development as a chemotherapeutic agent although its mechanism is unclear. When tested against other MPPs, ZnPP was the most effective DNA synthesis and cellular proliferation inhibitor while promoting apoptosis in telomerase positive but not telomerase negative cells. Concurrently, ZnPP down-regulated telomerase expression and was the best overall inhibitor of telomerase activity in intact cells and cellular extracts with IC50 and EC50  values of ca 2.5 and 6 µM, respectively. The natural fluorescence properties of ZnPP enabled direct imaging in cellular fractions using non-denaturing agarose gel electrophoresis, western blots, and confocal fluorescence microscopy. ZnPP localized to large cellular complexes (>600 kD) that contained telomerase and dysskerin as confirmed with immunocomplex mobility shift, immunoprecipitation, and immunoblot analyses. Confocal fluorescence studies showed that ZnPP co-localized with telomerase reverse transcriptase (TERT) and telomeres in the nucleus of synchronized S-phase cells. ZnPP also co-localized with TERT in the perinuclear regions of log phase cells but did not co-localize with telomeres on the ends of metaphase chromosomes, a site known to be devoid of telomerase complexes. Overall, these results suggest that ZnPP does not bind to telomeric sequences per se, but alternatively, interacts with other structural components of the telomerase complex to inhibit telomerase activity. In conclusion, ZnPP actively interferes with telomerase activity in neoplastic cells, thus promoting pro-apoptotic and anti-proliferative properties. These data support further development of natural or synthetic protoporphyrins for use as chemotherapeutic agents to augment current treatment protocols for neoplastic disease.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Protoporfirinas/farmacologia , Telomerase/metabolismo , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidores Enzimáticos/administração & dosagem , Células HEK293 , Humanos , Concentração Inibidora 50 , Microscopia Confocal , Protoporfirinas/administração & dosagem , Telomerase/antagonistas & inibidores , Telômero/metabolismo
4.
Gastroenterol Clin North Am ; 50(2): 305-322, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34024443

RESUMO

Viral acute gastroenteritis (AGE) is common and afflicts people of all ages. Nonviral causes of AGE are less common. Norovirus is a leading cause of sporadic cases and outbreaks of AGE across all ages. Universal rotavirus vaccination of infants has reduced frequency and severity of rotavirus AGE cases in children and indirectly reduced cases in older adults. Severe illness is more likely in persons at age extremes or with immunocompromising conditions. Viral causes of AGE can lead to protracted diarrheal illness in immunocompromised persons. Nucleic acid amplification tests are changing diagnostic testing algorithms.


Assuntos
Gastroenterite , Norovirus , Rotavirus , Idoso , Criança , Diarreia , Fezes , Gastroenterite/diagnóstico , Gastroenterite/epidemiologia , Humanos , Lactente
5.
J Virol ; 89(24): 12284-98, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26423948

RESUMO

UNLABELLED: Triggers and regulatory pathways that effectively link human cytomegalovirus (HCMV) major immediate early (MIE) latent-lytic switch activation with progeny production are incompletely understood. In the quiescently infected human NTera2 cell model of primitive neural stem cells, we found that costimulation with vasoactive intestinal peptide (V) and phorbol ester (P) synergistically activated viral infection, but this effect waned over time. Coupling retinoic acid (R), an inducer of neuronal differentiation, to VP pulse stimulation attenuated the decline in viral activity and promoted the spread of the active infection through concentric layers of neighboring cells as cellular differentiation progressed. R stimulation alone was unable to activate the infection. The MIE enhancer cis-regulatory mechanisms responsible for this result were characterized by a strategy of combinatorial mutagenesis of five cis-acting element types (retinoic acid receptor binding elements [RARE], cyclic AMP [cAMP] response elements [CRE], NF-κB binding sites [kB], serum response element, and ETS/ELK-1 binding site) and multiple methods of assessment. We found that the CRE and kB combination sets the preinduction enhancer tone, is the major initiator and amplifier of RVP-induced MIE gene expression, and cooperates with RARE during cellular differentiation to enhance viral spread. In predifferentiated NTera2, we also found that the CRE-kB combination functions as initiator and amplifier of unstimulated HCMV MIE gene expression and cooperatively interacts with RARE to enhance viral spread. We conclude that RVP-stimulated signaling cascades and cellular differentiation operate through the enhancer CRE-kB-RARE core in strengthening induction of HCMV MIE gene expression in linkage with viral propagation. IMPORTANCE: Cytomegalovirus-seropositive persons commonly lack detectable levels of cytomegalovirus replication, even when profoundly immunocompromised. In a human NTera2 cell model of primitive neural stem cells carrying resting cytomegalovirus genomes, we show that costimulation of protein kinase A and C-delta signaling cascades in conjunction with retinoic acid-induced neuronal differentiation brings about progeny virus propagation. Iterated DNA binding sites for retinoic acid receptor, CREB, and NF-κB family members in the cytomegalovirus major enhancer are at the crux in the pathway to HCMV activation. The stimulated CREB and NF-κB binding site combination vigorously initiates and amplifies the active cytomegalovirus infection and cooperates with activated retinoic acid receptor binding sites to further promote viral proliferation and spread between differentiated cells. These results support a paradigm in which a specific combination of stimuli coupled with cellular differentiation satisfies a core cis-activating code that unlocks enhancer silence to repower the cycle of cytomegalovirus propagation.


Assuntos
Infecções por Citomegalovirus/genética , Citomegalovirus/fisiologia , Elementos de Resposta , Transdução de Sinais , Replicação Viral/fisiologia , AMP Cíclico/metabolismo , Infecções por Citomegalovirus/metabolismo , Humanos , NF-kappa B/metabolismo , Tretinoína/metabolismo
6.
PLoS One ; 10(6): e0123119, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26107253

RESUMO

OBJECTIVES: Neurologic complications of human immunodeficiency virus (HIV) infection and acquired immune deficiency syndrome (AIDS) frequently lead to disability or death in affected patients. The aim of this study was to determine whether survival patterns differ between men and women with HIV/AIDS-related neurologic disease (neuro-AIDS). METHODS: Retrospective cohort data from a statewide surveillance database for HIV/AIDS were used to characterize survival following an HIV/AIDS-related neurologic diagnosis for men and women with one or more of the following conditions: cryptococcosis, toxoplasmosis, primary central nervous system lymphoma, progressive multifocal leukoencephalopathy, and HIV-associated dementia. A second, non-independent cohort was formed using university-based cases to confirm and extend the findings from the statewide data. Kaplan-Meier analysis was used to compare the survival experiences for men and women in the cohorts. Cox regression was employed to characterize survival while controlling for potential confounders in the study population. RESULTS: Women (n=27) had significantly poorer outcomes than men (n=198) in the statewide cohort (adjusted hazard ratio=2.31, 95% CI: 1.22 to 4.35), and a similar, non-significant trend was observed among university-based cases (n=17 women, 154 men). Secondary analyses suggested that this difference persisted over the course of the AIDS epidemic and was not attributable to differential antiretroviral therapy responses among men and women. CONCLUSIONS: The survival disadvantage of women compared to men should be confirmed and the mechanisms underlying this disparity elucidated. If this relationship is confirmed, targeted clinical and public health efforts might be directed towards screening, treatment, and support for women affected by neuro-AIDS.


Assuntos
Depressão/epidemiologia , Infecções por HIV/epidemiologia , Doenças do Sistema Nervoso/epidemiologia , Adulto , Depressão/etiologia , Depressão/patologia , Feminino , HIV/patogenicidade , Infecções por HIV/complicações , Infecções por HIV/virologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/patologia , Doenças do Sistema Nervoso/virologia , Fatores de Risco , Caracteres Sexuais
7.
J Virol ; 83(13): 6391-403, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19369332

RESUMO

The triggering mechanisms underlying reactivation of human cytomegalovirus (HCMV) in latently infected persons are unclear. During latency, HCMV major immediate-early (MIE) gene expression breaks silence to initiate viral reactivation. Using quiescently HCMV-infected human pluripotent embryonal NTera2 cells (NT2) to model HCMV reactivation, we show that vasoactive intestinal peptide (VIP), an immunomodulatory neuropeptide, immediately and dose-dependently (1 to 500 nM) activates HCMV MIE gene expression. This response requires the MIE enhancer cyclic AMP response elements (CRE). VIP quickly elevates CREB Ser133 and ATF-1 Ser63 phosphorylation levels, although the CREB Ser133 phosphorylation level is substantial at baseline. VIP does not change the level of HCMV genomes in nuclei, Oct4 (pluripotent cell marker), or hDaxx (cellular repressor of HCMV gene expression). VIP-activated MIE gene expression is mediated by cellular protein kinase A (PKA), CREB, and TORC2. VIP induces PKA-dependent TORC2 Ser171 dephosphorylation and nuclear entry, which likely enables MIE gene activation, as TORC2 S171A (devoid of Ser171 phosphorylation) exhibits enhanced nuclear entry and desilences the MIE genes in the absence of VIP stimulation. In conclusion, VIP stimulation of the PKA-CREB-TORC2 signaling cascade activates HCMV CRE-dependent MIE gene expression in quiescently infected NT2 cells. We speculate that neurohormonal stimulation via this signaling cascade is a possible means for reversing HCMV silence in vivo.


Assuntos
Antígenos Virais/metabolismo , Infecções por Citomegalovirus/virologia , Citomegalovirus/genética , Proteínas Imediatamente Precoces/metabolismo , Transdução de Sinais , Peptídeo Intestinal Vasoativo/farmacologia , Linhagem Celular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Citomegalovirus/efeitos dos fármacos , Infecções por Citomegalovirus/metabolismo , DNA Viral/genética , Relação Dose-Resposta a Droga , Regulação Viral da Expressão Gênica , Inativação Gênica , Humanos , Fosforilação , Fatores de Transcrição/metabolismo
8.
J Virol ; 83(6): 2728-42, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19129459

RESUMO

To better understand the components of an effective immune response to human immunodeficiency virus (HIV), the CD8(+) T-cell responses to HIV, hepatitis C virus (HCV), and cytomegalovirus (CMV) were compared with regard to frequency, immunodominance, phenotype, and interleukin-2 (IL-2) responsiveness. Responses were examined in rare patients exhibiting durable immune-mediated control over HIV, termed long-term nonprogressors (LTNP) or elite controllers, and patients with progressive HIV infection (progressors). The magnitude of the virus-specific CD8(+) T-cell response targeting HIV, CMV, and HCV was not significantly different between LTNP and progressors, even though their capacity to proliferate to HIV antigens was preserved only in LTNP. In contrast to HIV-specific CD8(+) T-cell responses of LTNP, HLA B5701-restricted responses within CMV pp65 were rare and did not dominate the total CMV-specific response. Virus-specific CD8(+) T cells were predominantly CD27(+)45RO(+) for HIV and CD27(-)45RA(+) for CMV; however, these phenotypes were highly variable and heavily influenced by the degree of viremia. Although IL-2 induced significant expansions of CMV-specific CD8(+) T cells in LTNP and progressors by increasing both the numbers of cells entering the proliferating pool and the number of divisions, the proliferative capacity of a significant proportion of HIV-specific CD8(+) T cells was not restored with exogenous IL-2. These results suggest that immunodominance by HLA B5701-restricted cells is specific to HIV infection in LTNP and is not a feature of responses to other chronic viral infections. They also suggest that poor responsiveness to IL-2 is a property of HIV-specific CD8(+) T cells of progressors that is not shared with responses to other viruses over which immunologic control is maintained.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por Citomegalovirus/imunologia , Infecções por HIV/imunologia , Hepatite C/imunologia , Interleucina-2/imunologia , Linfócitos T CD8-Positivos/química , Proliferação de Células , Citomegalovirus/imunologia , HIV/imunologia , Sobreviventes de Longo Prazo ao HIV , Antígenos HLA-B/imunologia , Hepacivirus/imunologia , Humanos , Antígenos Comuns de Leucócito/análise , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/análise
9.
Am J Obstet Gynecol ; 197(6): 608.e1-6, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18060949

RESUMO

OBJECTIVE: Cytomegalovirus infection causes adverse outcomes during pregnancy. Our objective was to determine the role of cytomegalovirus in modulating tumor necrosis factor (TNF)-related apoptosis-inducing ligand expression in the placenta. STUDY DESIGN: TNF-related apoptosis-inducing ligand messenger RNA and protein were quantified in cytomegalovirus-infected placental fibroblasts by polymerase chain reaction and enzyme-linked immunosorbent assays, respectively. Blocking antibodies against interferon and type I interferon receptor were applied to culture medium to characterize the role of type I interferon in cytomegalovirus-induced TNF-related apoptosis-inducing ligand upregulation. RESULTS: Expression of TNF-related apoptosis-inducing ligand messenger RNA and protein was increased in cytomegalovirus-infected placental fibroblasts, compared with uninfected controls. The cytomegalovirus-induced TNF-related apoptosis-inducing ligand messenger RNA upregulation was demonstrated across gestation, occurred in the absence of viral gene expression, and required cellular protein synthesis. TNF-related apoptosis-inducing ligand messenger RNA upregulation was markedly attenuated by inactivation of either type I interferon or its receptor. CONCLUSION: One mechanism by which cytomegalovirus infection causes unfavorable pregnancy outcomes may involve placental upregulation of TNF-related apoptosis-inducing ligand via an interferon-mediated pathway.


Assuntos
Infecções por Citomegalovirus/imunologia , Interferons/imunologia , Placenta/imunologia , Ligante Indutor de Apoptose Relacionado a TNF/biossíntese , Feminino , Humanos , Gravidez , Regulação para Cima , Replicação Viral/imunologia
10.
J Virol ; 81(12): 6669-81, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17301150

RESUMO

The human cytomegalovirus (HCMV) major immediate-early (MIE) enhancer contains five functional cyclic AMP (cAMP) response elements (CRE). Because the CRE in their native context do not contribute appreciably to MIE enhancer/promoter activity in lytically infected human fibroblasts and NTera2 (NT2)-derived neurons, we postulated that they might have a role in MIE enhancer/promoter reactivation in quiescently infected cells. Here, we show that stimulation of the cAMP signaling pathway by treatment with forskolin (FSK), an adenylyl cyclase activator, greatly alleviates MIE enhancer/promoter silencing in quiescently infected NT2 neuronal precursors. The effect is immediate, independent of de novo protein synthesis, associated with the phosphorylation of ATF-1 serine 63 and CREB serine 133, dependent on protein kinase A (PKA) and the enhancer's CRE, and linked to viral-lytic-cycle advancement. Coupling of FSK treatment with the inhibition of either histone deacetylases or protein synthesis synergistically activates MIE gene expression in a manner suggesting that MIE enhancer/promoter silencing is optimally relieved by an interplay of multiple regulatory mechanisms. In contrast, MIE enhancer/promoter silence is not overcome by stimulation of the gamma interferon (IFN-gamma) signaling pathway, despite the enhancer having two IFN-gamma-activated-site-like elements. We conclude that stimulation of the cAMP/PKA signaling pathway drives CRE-dependent MIE enhancer/promoter activation in quiescently infected cells, thus exposing a potential mode of regulation in HCMV reactivation.


Assuntos
AMP Cíclico/metabolismo , Citomegalovirus/genética , Elementos Facilitadores Genéticos , Inativação Gênica , Genes Precoces , Regiões Promotoras Genéticas , Linhagem Celular , DNA Viral/genética , Humanos , Interferon gama/metabolismo , Modelos Genéticos , Fosforilação , RNA Viral/genética , Serina/química , Transdução de Sinais
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