RESUMEN
Benzo[b]thiophene heterocycles are important components of many important small molecule pharmaceuticals and drug candidates as well as organic semiconducting materials. Many methods have been developed for the construction of a benzo[b]thiophene core via cyclization reaction of alkynes. Although few catalytic reactions were disclosed, most methods rely on stoichiometric activation of alkynes. Here we report an efficient method for the synthesis of 2-substituted benzo[b]thiophenes from 2-alkynyl thioanisoles catalyzed by a gold(i)-IPr hydroxide that is applicable to a wide range of substrates with diverse electronic and steric properties. Additionally, we demonstrate experimentally that the acid additive and its conjugate base are essential to catalyst turnover.
RESUMEN
Tropical filamentous marine cyanobacteria have emerged as a viable source of novel bioactive natural products for drug discovery and development. In the present study, aplysiatoxin (1), debromoaplysiatoxin (2) and anhydrodebromoaplysiatoxin (3), as well as two new analogues, 3-methoxyaplysiatoxin (4) and 3-methoxydebromoaplysiatoxin (5), are reported for the first time from the marine cyanobacterium Trichodesmium erythraeum. The identification of the bloom-forming cyanobacterial strain was confirmed based on phylogenetic analysis of its 16S rRNA sequences. Structural determination of the new analogues was achieved by extensive NMR spectroscopic analysis and comparison with NMR spectral data of known compounds. In addition, the antiviral activities of these marine toxins were assessed using Chikungunya virus (CHIKV)-infected cells. Post-treatment experiments using the debrominated analogues, namely compounds 2, 3 and 5, displayed dose-dependent inhibition of CHIKV when tested at concentrations ranging from 0.1 µM to 10.0 µM. Furthermore, debromoaplysiatoxin (2) and 3-methoxydebromoaplysiatoxin (5) exhibited significant anti-CHIKV activities with EC50 values of 1.3 µM and 2.7 µM, respectively, and selectivity indices of 10.9 and 9.2, respectively.
Asunto(s)
Antivirales , Virus Chikungunya/efectos de los fármacos , Cianobacterias/química , Toxinas de Lyngbya/farmacología , Animales , Línea Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cricetinae , Relación Dosis-Respuesta a Droga , Eutrofización , Humanos , Toxinas de Lyngbya/química , Espectroscopía de Resonancia Magnética , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/biosíntesis , Ensayo de Placa ViralRESUMEN
Chikungunya virus (CHIKV) is a mosquito-transmitted virus that has reemerged as a significant public health threat in the last decade. Since the 2005-2006 chikungunya fever epidemic in the Indian Ocean island of La Réunion, millions of people in more than 40 countries have been infected. Despite this, there is currently no antiviral treatment for chikungunya infection. In this study, an immunofluorescence-based screening platform was developed to identify potential inhibitors of CHIKV infection. A primary screen was performed using a highly purified natural product compound library, and 44 compounds exhibiting ≥70% inhibition of CHIKV infection were identified as positive hits. Among these, four were selected for dose-dependent inhibition assays to confirm their anti-CHIKV activity. Harringtonine, a cephalotaxine alkaloid, displayed potent inhibition of CHIKV infection (50% effective concentration [EC(50)] = 0.24 µM) with minimal cytotoxicity and was selected for elucidation of its antiviral mechanism. Time-of-addition studies, cotreatment assays, and direct transfection of viral genomic RNA indicated that harringtonine inhibited an early stage of the CHIKV replication cycle which occurred after viral entry into cells. In addition, quantitative reverse transcription-PCR (qRT-PCR) and Western blot analyses indicated that harringtonine affects CHIKV RNA production as well as viral protein expression. Treatment of harringtonine against Sindbis virus, a related alphavirus, suggested that harringtonine could inhibit other alphaviruses. This study suggests for the first time that harringtonine exerts its antiviral effects by inhibiting CHIKV viral protein synthesis.
Asunto(s)
Antivirales/farmacología , Productos Biológicos/farmacología , Virus Chikungunya/efectos de los fármacos , Harringtoninas/farmacología , Biosíntesis de Proteínas/efectos de los fármacos , ARN Viral/antagonistas & inhibidores , Replicación Viral/efectos de los fármacos , Aedes , Animales , Antivirales/aislamiento & purificación , Productos Biológicos/aislamiento & purificación , Línea Celular , Virus Chikungunya/genética , Virus Chikungunya/crecimiento & desarrollo , Cricetinae , Relación Dosis-Respuesta a Droga , Técnica del Anticuerpo Fluorescente , Expresión Génica/efectos de los fármacos , Harringtoninas/aislamiento & purificación , Ensayos Analíticos de Alto Rendimiento , Humanos , ARN Viral/genética , Virus Sindbis/efectos de los fármacos , Virus Sindbis/genética , Virus Sindbis/crecimiento & desarrollo , Bibliotecas de Moléculas Pequeñas/aislamiento & purificación , Bibliotecas de Moléculas Pequeñas/farmacología , Transducción GenéticaRESUMEN
BACKGROUND: The optimal treatment of early syphilis (primary, secondary and early latent) in HIV-infected patients remains controversial. The Center for Diseases Control STD Treatment Guidelines recommended 1 dose of benzathine penicillin G (BPG) regardless of HIV infection. However, many providers modify the treatment for early syphilis. METHODS: We performed a retrospective chart review of all cases of early syphilis with positive serologic test results in HIV-infected patients from May 2006 to May 2011 in 2 large, urban HIV clinics. Early syphilis includes primary, secondary, and early latent syphilis. Serological failure was defined as a lack of 4-fold decrease in rapid plasma reagent (RPR) titers 9 to 12 months after syphilis treatment. Patients whose RPR titers decreased after treatment and subsequently increased 4-fold at 9 to 12 months were excluded from the analysis of serological response because of possibility as "reinfection". Baseline characteristics were tested as predictive factors of serological failure using a univariate and multivariate logistic regression model, respectively. RESULTS: Of 560 patients with confirmed cases of early syphilis, 51 (9.0%) experienced serological failure. Multivariate logistic regression modeling demonstrated that the predictive factors associated with serological failure after early syphilis treatment were baseline RPR titer ≤ 1:16 (OR 3.91 [95% CI, 2.04-7.47]), a previous history of syphilis (OR 3.12 [95% CI, 1.55-6.26]), and a CD4 T-cell count below 350 cells/ml (OR 2.41 [95% CI, 1.27-4.56]). Of note, type of syphilis treatment (1 dose versus 3 doses of BPG) did not appear to affect the proportion of serological failure (4% versus 10%, P = 0.29), however the power of this study to detect small differences was limited. CONCLUSIONS: HIV-infected patients with baseline RPR titer ≤1:16, syphilis history, and/or a CD4 T-cell count <350 cells/ml should be closely monitored for serologic failure after early syphilis treatment. This study did not detect a substantial difference between treatment with > 1 dose of BPG and decreased frequency of serological failure, supporting the current recommendation that one dose of BPG is adequate treatment for early syphilis in HIV-infected patients.
Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Infecciones Oportunistas Relacionadas con el SIDA/inmunología , Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Penicilina G Benzatina/uso terapéutico , Sífilis/tratamiento farmacológico , Adulto , Recuento de Linfocito CD4 , Monitoreo de Drogas , Femenino , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Pruebas Serológicas , Sífilis/inmunología , Resultado del TratamientoRESUMEN
Positive-sense RNA viruses modify intracellular calcium stores, endoplasmic reticulum and Golgi apparatus (Golgi) to generate membranous replication organelles known as viral factories. Viral factories provide a conducive and substantial enclave for essential virus replication via concentrating necessary cellular factors and viral proteins in proximity. Here, we identified the vital role of a broad-spectrum antiviral, peruvoside in limiting the formation of viral factories. Mechanistically, we revealed the pleiotropic cellular effect of Src and PLC kinase signaling via cyclin-dependent kinase 1 signaling leads to Golgi-specific brefeldin A-resistance guanine nucleotide exchange factor 1 (GBF1) phosphorylation and Golgi vesiculation by peruvoside treatment. The ramification of GBF1 phosphorylation fosters GBF1 deprivation consequentially activating downstream antiviral signaling by dampening viral factories formation. Further investigation showed signaling of ERK1/2 pathway via cyclin-dependent kinase 1 activation leading to GBF1 phosphorylation at Threonine 1337 (T1337). We also showed 100% of protection in peruvoside-treated mouse model with a significant reduction in viral titre and without measurable cytotoxicity in serum. These findings highlight the importance of dissecting the broad-spectrum antiviral therapeutics mechanism and pave the way for consideration of peruvoside, host-directed antivirals for positive-sense RNA virus-mediated disease, in the interim where no vaccine is available.
RESUMEN
Dengue and Zika viruses are mosquito-borne flaviviruses burdening millions every year with hemorrhagic fever and neurological symptoms. Baicalein was previously reported as a potential anti-flaviviral candidate and halogenation of flavones and flavanones potentiated their antiviral efficacies. Here, we reported that a chemically modified 8-bromobaicalein effectively inhibited all dengue serotypes and Zika viruses at 0.66-0.88 micromolar in cell-based system. The compound bound to dengue serotype 2 conserved pocket and inhibited the dengue RdRp activity with 6.93 fold more than the original baicalein. Moreover, the compound was mildly toxic against infant and adult C57BL/6 mice despite administering continuously for 7 days. Therefore, the 8-bromobaicalein should be investigated further in pharmacokinetics and efficacy in an animal model.
Asunto(s)
Virus del Dengue , Dengue , Flavivirus , Infección por el Virus Zika , Virus Zika , Animales , Ratones , Dengue/tratamiento farmacológico , Ratones Endogámicos C57BLRESUMEN
The COVID-19 pandemic has brought about unprecedented medical and healthcare challenges worldwide. With the continual emergence and spread of new COVID-19 variants, four drug compound libraries were interrogated for their antiviral activities against SARS-CoV-2. Here, we show that the drug screen has resulted in 121 promising anti-SARS-CoV-2 compounds, of which seven were further shortlisted for hit validation: citicoline, pravastatin sodium, tenofovir alafenamide, imatinib mesylate, calcitriol, dexlansoprazole, and prochlorperazine dimaleate. In particular, the active form of vitamin D, calcitriol, exhibits strong potency against SARS-CoV-2 on cell-based assays and is shown to work by modulating the vitamin D receptor pathway to increase antimicrobial peptide cathelicidin expression. However, the weight, survival rate, physiological conditions, histological scoring, and virus titre between SARS-CoV-2 infected K18-hACE2 mice pre-treated or post-treated with calcitriol were negligible, indicating that the differential effects of calcitriol may be due to differences in vitamin D metabolism in mice and warrants future investigation using other animal models.
RESUMEN
The mosquito-borne Zika virus is an emerging pathogen from the Flavivirus genus for which there are no approved antivirals or vaccines. Using the clinically validated PDK-53 dengue virus vaccine strain as a backbone, we created a chimeric dengue/Zika virus, VacDZ, as a live attenuated vaccine candidate against Zika virus. VacDZ demonstrates key markers of attenuation: small plaque phenotype, temperature sensitivity, attenuation of neurovirulence in suckling mice, and attenuation of pathogenicity in interferon deficient adult AG129 mice. VacDZ may be administered as a traditional live virus vaccine, or as a DNA-launched vaccine that produces live VacDZ in vivo after delivery. Both vaccine formulations induce a protective immune response against Zika virus in AG129 mice, which includes neutralising antibodies and a strong Th1 response. This study demonstrates that VacDZ is a safe and effective vaccine candidate against Zika virus.
RESUMEN
Chikungunya virus (CHIKV) is an alphavirus that causes a febrile illness accompanied by myalgia and arthralgia. Despite having re-emerged as a significant public health threat, there are no approved therapeutics or prophylactics for CHIKV infection. In this study, we explored the anti-CHIKV effects of proteasome inhibitors and their potential mechanism of antiviral action. A panel of proteasome inhibitors with different functional groups reduced CHIKV infectious titers in a dose-dependent manner. Bortezomib, which has been FDA-approved for multiple myeloma and mantle cell lymphoma, was further investigated in downstream studies. The inhibitory activities of bortezomib were confirmed using different cellular models and CHIKV strains. Time-of-addition and time-of-removal studies suggested that bortezomib inhibited CHIKV at an early, post-entry stage of replication. In western blot analysis, bortezomib treatment resulted in a prominent decrease in structural protein levels as early as 6 hpi. Contrastingly, nsP4 levels showed strong elevations across all time-points. NsP2 and nsP3 levels showed a fluctuating trend, with some elevations between 12 to 20 hpi. Finally, qRT-PCR data revealed increased levels of both positive- and negative-sense CHIKV RNA at late stages of infection. It is likely that the reductions in structural protein levels is a major factor in the observed reductions in virus titer, with the alterations in non-structural protein ratios potentially being a contributing factor. Proteasome inhibitors like bortezomib likely disrupt CHIKV replication through a variety of complex mechanisms and may display a potential for use as therapeutics against CHIKV infection. They also represent valuable tools for studies of CHIKV molecular biology and virus-host interactions.
Asunto(s)
Antivirales/farmacología , Bortezomib/farmacología , Virus Chikungunya/efectos de los fármacos , Proteínas Virales/antagonistas & inhibidores , Proteínas Virales/biosíntesis , Replicación Viral/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Pruebas de Sensibilidad Microbiana , Carga ViralRESUMEN
Enterovirus A71 (EV-A71) is one of the aetiological agents for the hand, foot and mouth disease (HFMD) in young children and a potential cause of neurological complications in afflicted patients. Since its discovery in 1969, there remains no approved antiviral for EV-A71 and other HFMD-causing enteroviruses. We set out to address the lack of therapeutics against EV-A71 by screening an FDA-approved drug library and found an enrichment of hits including pyrimidine antimetabolite, gemcitabine which showed 90.2% of inhibition on EV-A71 infection. Gemcitabine and other nucleoside analogs, LY2334737 and sofosbuvir inhibition of EV-A71 infection were disclosed using molecular and proteomic quantification, and in vitro and in vivo efficacy evaluation. Gemcitabine displayed a significant reduction of infectious EV-A71 titres by 2.5 logs PFU/mL and was shown to target the early stage of EV-A71 viral RNA and viral protein synthesis process especially via inhibition of the RNA dependent RNA polymerase. In addition, the drug combination study of gemcitabine's synergistic effects with interferon-ß at 1:1 and 1:2 ratio enhanced inhibition against EV-A71 replication. Since gemcitabine is known to metabolize rapidly in vivo, other nucleoside analogs, LY2334737 and sofosbuvir conferred protection in mice against lethal EV-A71 challenge by potentially reducing the death rate, viral titers as well on virus-induced pathology in the limb muscle tissue of mice. Additionally, we found that gemcitabine is competent to inhibit other positive-sense RNA viruses of the Flaviviridae and Togaviridae family. Overall, these drugs provide new insights into targeting viral factors as a broad-spectrum antiviral strategy with potential therapeutic value for future development and are worthy of potential clinical application.
Asunto(s)
Antivirales/administración & dosificación , Desoxicitidina/análogos & derivados , Enterovirus Humano A/efectos de los fármacos , Infecciones por Enterovirus/tratamiento farmacológico , Pirimidinas/administración & dosificación , Animales , Antivirales/química , Desoxicitidina/administración & dosificación , Desoxicitidina/química , Reposicionamiento de Medicamentos , Enterovirus Humano A/genética , Enterovirus Humano A/fisiología , Infecciones por Enterovirus/virología , Humanos , Ratones , Ratones Endogámicos BALB C , Pirimidinas/química , ARN Viral/genética , ARN Viral/metabolismo , Replicación Viral/efectos de los fármacos , GemcitabinaRESUMEN
AIM: The aim of the present study is to evaluate the state anxiety (the present state of mind), trait anxiety (general anxiety), as well as perceived stress in women undergoing in vitro fertilization (IVF) treatment at three stages: T1 (on the day of start of stimulation), T2 (on the day of embryo transfer), and T3 (10 days after embryo transfer). The data at T3 level were collected telephonically. METHODOLOGY: The present study was carried out on 137 women undergoing IVF intracytoplasmic sperm injection cycle at four different clinics of four cities from October to April 2016. State-trait anxiety inventory (Spielberger) and perceived stress scale (Okun, et al.) were used as the tools. STATISTICAL ANALYSIS: The analysis was done at two levels; descriptive and inferential (analysis of variance [ANOVA], Student's t-test, Levene's test) using SPSS v16. RESULTS: The state anxiety was higher at all the three levels than trait anxiety. The overt anxiety was highest at T3 level (mean = 45.77) followed by T1 level (mean = 44.23) and T2 level (mean = 43.04). Perceived stress was elevated at T1 level (mean = 17.93) followed by T3 level (mean = 17.28) and T2 level (mean = 16.72). The results of ANOVA showed a significant difference in anxiety among all the three levels (P = 0.036), but no significant difference was found for perceived stress (P = 0.169). t-test revealed that there was a significant difference between state and trait anxiety at T1, T2, and T3 levels (P = 0.01, P = 0.21, P = 0.00, respectively). A significant difference was only seen between the T1 and T2 levels in perceived stress (P = 0.052). In state anxiety, a significant difference was observed only between T2 and T3 levels (P = 0.23). CONCLUSION: It was observed that anxiety and stress are present in women throughout the treatment. The waiting period (T3) is the most anxious for them and their level of state anxiety is higher compared to their trait anxiety. Perceived stress is observed to be more on the day of start of stimulation followed by the waiting period.
RESUMEN
BACKGROUND: Psychological conditions are experiences of the conscious and unconscious elements of the work context, which revolve around workers' perceptions of feeling either engaged or disengaged with the assigned tasks. In the psychosocial work environment of hazardous industries like petrochemicals where production lasts twenty-four hours a day and continues seven-days-a-week, a psychologically available worker is extremely important. Psychological availability refers to when workers who are physically, emotionally and psychologically engaged at the moment of performing tasks. OBJECTIVE: The broad objective of this study was to investigate the direct and indirect effects of behavioral factors on the psychological and physiological health of workers. METHODS: The latest, second generation technique, which is structural equation modeling, is used to identify the relationships between behavioral antecedents and health outcomes. A total of 277 technical workers participated, aged between 20 and 49 and were healthy in all aspects. RESULTS: The study results showed quantitative demands, emotional demands, work-family conflict, and job insecurity were significantly associated with both psychological (stress) and physiological (Body Mass Index) factors. The social support of colleagues produced mixed findings with direct and indirect paths. Stress also significantly mediates the psychosocial factors and burnout of the workers. CONCLUSION: The study concluded that workers were physically available, but they experienced distractions as members of social systems, affecting their physiological and psychological health.
Asunto(s)
Industria Química , Satisfacción en el Trabajo , Lugar de Trabajo/psicología , Adulto , Índice de Masa Corporal , Agotamiento Profesional/psicología , Emociones , Conflicto Familiar , Humanos , Persona de Mediana Edad , Apoyo Social , Estrés Psicológico , Equilibrio entre Vida Personal y Laboral , Carga de Trabajo/psicología , Adulto JovenRESUMEN
Occurrence of pneumothorax in silicosis is rare and when it occurs, pneumothorax is usually unilateral. We report here a patient with accelerated silicosis who presented with bilateral spontaneous pneumothoraces occurring simultaneously. The rarity of its clinical presentation in the form of bilateral simultaneous spontaneous pneumothorax combined with the typical clinical and radiological features of accelerated silicosis with tuberculosis make us to report this case.
Asunto(s)
Neumotórax/diagnóstico , Neumotórax/etiología , Silicosis/complicaciones , Adulto , Humanos , Masculino , Tomografía Computarizada por Rayos XRESUMEN
The plaque assay is an essential method for quantification of infectious virus titer. Cells infected with virus particles are overlaid with a viscous substrate. A suitable incubation period results in the formation of plaques, which can be fixed and stained for visualization. Here, we describe a method for measuring Chikungunya virus (CHIKV) titers via virus plaque assays.
Asunto(s)
Virus Chikungunya/crecimiento & desarrollo , Ensayo de Placa Viral/métodos , Animales , Línea Celular , Carga Viral/métodosRESUMEN
Chikungunya virus (CHIKV) is a re-emerging mosquito-borne alphavirus that has recently engendered large epidemics around the world. There is no specific antiviral for treatment of patients infected with CHIKV, and development of compounds with significant anti-CHIKV activity that can be further developed to a practical therapy is urgently required. Andrographolide is derived from Andrographis paniculata, a herb traditionally used to treat a number of conditions including infections. This study sought to determine the potential of andrographolide as an inhibitor of CHIKV infection. Andrographolide showed good inhibition of CHIKV infection and reduced virus production by approximately 3log10 with a 50% effective concentration (EC50) of 77 µM without cytotoxicity. Time-of-addition and RNA transfection studies showed that andrographolide affected CHIKV replication and the activity of andrographolide was shown to be cell type independent. This study suggests that andrographolide has the potential to be developed further as an anti-CHIKV therapeutic agent.
Asunto(s)
Antivirales/farmacología , Virus Chikungunya/efectos de los fármacos , Diterpenos/farmacología , Andrographis/química , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Fiebre Chikungunya/tratamiento farmacológico , Fiebre Chikungunya/virología , Virus Chikungunya/fisiología , Cricetinae , Dosificación de Gen/efectos de los fármacos , Regulación Viral de la Expresión Génica/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/farmacología , ARN Viral , Ensayo de Placa Viral , Replicación Viral/efectos de los fármacosRESUMEN
Solitary fibrous tumor (SFT) represents a spectrum of mesenchymal tumors, encompassing tumors previously termed hemangiopericytoma, as having intermediate biological potential. Though they can occur at any site, lower distal extremity is a rare site and recurrence in it is extremely rare. Behavior of SFT is unpredictable. Histomorphology and clinical follow-up have poor correlation. The most important single indicator of clinical outcome is complete excision of the tumor at the time of primary presentation. Tumors with positive margins require close follow-up for several years owing to the potential for late local recurrence.
RESUMEN
Chikungunya virus (CHIKV) has re-emerged as a significant public health threat since the 2005 chikungunya fever epidemic in La Réunion. Driven by the medical importance of this virus, as well as the lack of approved antivirals, research into the field of CHIKV antivirals has recently intensified. Potential therapeutics that have been reported to show anti-CHIKV activity in vitro range from known broad-spectrum antivirals like chloroquine to novel strategies involving RNA silencing technology. Although most of the earlier efforts focused on compounds that target host components, some recent studies have reported viral targets such as nonstructural proteins. This article examines the reported in vitro and in vivo efficacies, as well as the therapeutic potential of these antiviral compounds.