Combination Therapy of Curcumin and Disulfiram Synergistically Inhibits the Growth of B16-F10 Melanoma Cells by Inducing Oxidative Stress

Oxidative stress plays a central role in the pathophysiology of melanoma. Curcumin (CUR) is a polyphenolic phytochemical that stimulates reactive oxygen species (ROS) production, while disulfiram (DSS) is a US FDA-approved drug for the treatment of alcoholism that can act by inhibiting the intracellular antioxidant system. Therefore, we hypothesized that they act synergistically against melanoma cells. Herein, we aimed to study the antitumor potential of the combination of CUR with DSS in B16-F10 melanoma cells using in vitro and in vivo models. The cytotoxic effects of different combination ratios of CUR and DSS were evaluated using the Alamar Blue method, allowing the production of isobolograms. Apoptosis detection, DNA fragmentation, cell cycle distribution, and mitochondrial superoxide levels were quantified by flow cytometry. Tumor development in vivo was evaluated using C57BL/6 mice bearing B16-F10 cells. The combinations ratios of 1:2, 1:3, and 2:3 showed synergic effects. B16-F10 cells treated with these combinations showed improved apoptotic cell death and DNA fragmentation. Enhanced mitochondrial superoxide levels were observed at combination ratios of 1:2 and 1:3, indicating increased oxidative stress. In vivo tumor growth inhibition for CUR (20 mg/kg), DSS (60 mg/kg), and their combination were 17.0%, 19.8%, and 28.8%, respectively. This study provided data on the potential cytotoxic activity of the combination of CUR with DSS and may provide a useful tool for the development of a therapeutic combination against melanoma.

Essential Oils of Duguetia Species A. St. Hill (Annonaceae): Chemical Diversity and Pharmacological Potential

Duguetia A. St. Hill (Annonaceae) is recognized as one of the major genera with approximately 100 species, 67 of which are found in Brazil (29 of those are endemic). They are arboreal species with edible fruits known as “pindaíba”, “pindaíva” “pinha”, and “envira” in Brazil. Many Duguetia species, in particular, have been used in traditional medicine to treat renal colic, stomachache, rheumatism, cough, toothache, muscle pain, fever, gastrointestinal pain, and breathing difficulties. In this study, we reviewed the chemical constituents and pharmacological properties of essential oils (EOs) from Duguetia species. A total of 12 species were found, along with their EO chemical constituents and bioactivities. Bicyclogermacrene, humulene epoxide II, spathulenol, germacrene D, caryophyllene oxide, viridiflorene, α-pinene, β-caryophyllene, and β-pinene were the main chemical constituents reported. The pharmacological effects of Duguetia species EOs included anti-inflammatory, antinociceptive, antibacterial, antifungal, antioxidant, anti-trypanosoma, cytotoxic and antitumor properties. This information adds to our understanding of the potential of the EOs of Duguetia species.

Essential Oil from Bark of Aniba parviflora (Meisn.) Mez (Lauraceae) Reduces HepG2 Cell Proliferation and Inhibits Tumor Development in a Xenograft Model

Aniba parviflora (Meisn.) Mez (Lauraceae) is an aromatic plant of the Amazon rainforest, which has a tremendous commercial value in the perfumery industry; it is popularly used as flavoring sachets and aromatic baths. In Brazilian folk medicine, A. parviflora is used to treat victims of snakebites. Herein, we analyzed the chemical composition of A. parviflora bark essential oil (EO) and its effect on the growth of human hepatocellular carcinoma HepG2 cells in vitro and in vivo. EO was obtained by hydrodistillation and characterized by GC-MS and GC-FID. The main constituents of EO were linalool (16.3±3.15), α-humulene (14.5±2.41 %), δ-cadinene (10.2±1.09 %), α-copaene (9.51±1.12 %) and germacrene B (7.58±2.15 %). Initially, EO's cytotoxic effect was evaluated against five cancer cell lines (HepG2, MCF-7, HCT116, HL-60 and B16-F10) and one non-cancerous one (MRC-5), using the Alamar blue method after 72 h of treatment. The calculated IC₅₀ values were 9.05, 22.04, >50, 15.36, 17.57, and 30.46 μg/mL, respectively. The best selectivity was for HepG2 cells with a selective index of 3.4. DNA Fragmentation and cell cycle distribution were quantified in HepG2 cells by flow cytometry after a treatment period of 24 and 48 h. The effect of EO on tumor development in vivo was evaluated in a xenograft model using C.B-17 SCID mice engrafted with HepG2 cells. In vivo tumor growth inhibition of HepG2 xenograft at the doses of 40 and 80 mg/kg were 12.1 and 62.4 %, respectively.

Essential oil from leaves of Conobea scoparioides (Cham. & Schltdl.) Benth. (Plantaginaceae) causes cell death in HepG2 cells and inhibits tumor development in a xenograft model

Conobea scoparioides (Cham. & Schltdl.) Benth. (syn. Sphaerotheca scoparioides Cham. & Schldtl.) (Plantaginaceae), popularly known as "pataqueira", "vassourinha-do-brejo" and/or "hierba-de-sapo", is a popular medicinal plant used to treat leishmaniasis, pain and beriberi. In addition, inhibition of cell adhesion, antioxidant, cytotoxic and leishmanicidal activities of compounds or fractions of C. scoparioides have been reported. In the present work, chemical constituents and in vitro and in vivo anti-liver cancer potential of essential oil (EO) from leaves of C. scoparioides were investigated using human hepatocellular carcinoma HepG2 cells as a cell model. EO was obtained by hydrodistillation using a Clevenger-type apparatus and characterized by GC-MS and GC-FID. The in vitro cytotoxic effect was evaluated on three human cancer cell lines (MCF-7, HepG2 and HCT116) and one human non-cancerous cell line (MRC-5) using the Alamar blue assay. Phosphatidylserine externalization and cell cycle distribution were quantified in HepG2 cells by flow cytometry after 48 h incubation. The effectiveness of EO in anti-liver cancer model was studied with HepG2 cells grafted on C.B. 17 SCID mice. The main constituents of EO were thymol methyl ether (62 %), thymol (16 %) and α-phellandrene (14 %). EO displayed an in vitro cytotoxic effect against all human cancer cell lines and caused externalization of phosphatidylserine and DNA fragmentation in HepG2 cells, suggesting induction of apoptotic-like cell death. In vivo tumor mass inhibition of 36.7 and 55.8 % was observed for treatment with EO at doses of 40 and 80 mg/kg, respectively. These results indicate in vitro and in vivo anti-liver cancer potential of EO from leaves of C. scoparioides.

Adverse birth outcomes associated with Zika virus exposure during pregnancy in São José do Rio Preto, Brazil

OBJECTIVES

We aimed to report the first 54 cases of pregnant women infected by Zika virus (ZIKV) and their virologic and clinical outcomes, as well as their newborns' outcomes, in 2016, after the emergence of ZIKV in dengue-endemic areas of São Paulo, Brazil.

METHODS

This descriptive study was performed from February to October 2016 on 54 quantitative real-time PCR ZIKV-positive pregnant women identified by the public health authority of São José do Rio Preto, São Paulo, Brazil. The women were followed and had clinical and epidemiologic data collected before and after birth. Adverse outcomes in newborns were analysed and reported. Urine or blood samples from newborns were collected to identify ZIKV infection by reverse transcription PCR (RT-PCR).

RESULTS

A total of 216 acute Zika-suspected pregnant women were identified, and 54 had the diagnosis confirmed by RT-PCR. None of the 54 women miscarried. Among the 54 newborns, 15 exhibited adverse outcomes at birth. The highest number of ZIKV infections occurred during the second and third trimesters. No cases of microcephaly were reported, though a broad clinical spectrum of outcomes, including lenticulostriate vasculopathy, subependymal cysts, and auditory and ophthalmologic disorders, were identified. ZIKV RNA was detected in 18 of 51 newborns tested and in eight of 15 newborns with adverse outcomes.

CONCLUSIONS

Although other studies have associated many newborn outcomes to ZIKV infection during pregnancy, these same adverse outcomes were rare or nonexistent in this study. The clinical presentation the newborns we studied was mild compared to other reports, suggesting that there is significant heterogeneity in congenital Zika infection.

Zika Virus Infection and Solid Organ Transplantation: A New Challenge

Public health concerns exist surrounding the epidemic of the Zika virus (ZIKV) and the rapid growth of transplantation in developing countries, including endemic zones of active arbovirus transmission, as well as travel to such regions by potential organ donors and recipients. Few data exist regarding the clinical characteristics of ZIKV infection in immunocompromised hosts. Laboratory screening protocols for transplantation to differentiate ZIKV infections from other endemic viral diseases and for the detection of possible donor-derived infection have not been stated. The diagnosis of ZIKV infection remains a challenge, fueled by the lack of standardized commercially available diagnostic tests and validated reference diagnostic laboratories, as well as the limited duration of ZIKV viremia. In this small series, ZIKV infection in renal and liver recipients presented without rash, conjunctivitis, or neurological symptoms, and with abnormal graft function, thrombocytopenia, and bacterial superinfection. We report the first case series of ZIKV infection in solid organ recipients, with a description of clinical and laboratory features and therapeutic management.

Isolation and Characterization of Madariaga Virus from a Horse in Paraíba State, Brazil

Madariaga virus (MADV), the new species designation for the South American isolates of eastern equine encephalitis virus (EEEV), is genetically divergent and substantially different in ecology and pathogenesis from North American EEEV strains. We isolated and characterized a MADV isolate obtained from a horse in Brazil. Our results support previous phylogenetic studies showing there are three genetically distinct MADV lineages. The MADV isolate from Paraíba State belongs to the South American lineage III and is closely related to Peruvian, Colombian and Venezuelan isolates.

A phylogenetic analysis using full-length viral genomes of South American dengue serotype 3 in consecutive Venezuelan outbreaks reveals a novel NS5 mutation

Dengue virus currently causes 50-100 million infections annually. Comprehensive knowledge about the evolution of Dengue in response to selection pressure is currently unavailable, but would greatly enhance vaccine design efforts. In the current study, we sequenced 187 new dengue virus serotype 3 (DENV-3) genotype III whole genomes isolated from Asia and the Americas. We analyzed them together with previously-sequenced isolates to gain a more detailed understanding of the evolutionary adaptations existing in this prevalent American serotype. In order to analyze the phylogenetic dynamics of DENV-3 during outbreak periods; we incorporated datasets of 48 and 11 sequences spanning two major outbreaks in Venezuela during 2001 and 2007-2008, respectively. Our phylogenetic analysis of newly sequenced viruses shows that subsets of genomes cluster primarily by geographic location, and secondarily by time of virus isolation. DENV-3 genotype III sequences from Asia are significantly divergent from those from the Americas due to their geographical separation and subsequent speciation. We measured amino acid variation for the E protein by calculating the Shannon entropy at each position between Asian and American genomes. We found a cluster of seven amino acid substitutions having high variability within E protein domain III, which has previously been implicated in serotype-specific neutralization escape mutants. No novel mutations were found in the E protein of sequences isolated during either Venezuelan outbreak. Shannon entropy analysis of the NS5 polymerase mature protein revealed that a G374E mutation, in a region that contributes to interferon resistance in other flaviviruses by interfering with JAK-STAT signaling was present in both the Asian and American sequences from the 2007-2008 Venezuelan outbreak, but was absent in the sequences from the 2001 Venezuelan outbreak. In addition to E, several NS5 amino acid changes were unique to the 2007-2008 epidemic in Venezuela and may give additional insight into the adaptive response of DENV-3 at the population level.

Detection of herpesvirus DNA by the polymerase chain reaction (PCR) in vitreous samples from patients with necrotising retinitis

AIMS

Viral uveitis and retinitis, usually caused by herpesviruses, are common in immunosuppressed patients. The diagnosis of viral anterior uveitis and retinitis is usually clinical. The polymerase chain reaction (PCR) has been used for the diagnosis of some viral infections, especially those caused by herpesviruses. This paper reports the use of PCR in the diagnosis of viral retinitis in vitreous samples from Brazilian patients.

METHODS

PCR was used for the diagnosis of necrotising retinitis in vitreous samples from patients from the Hospital São Geraldo, Universidade Federal de Minas Gerais, Brazil. The vitreous samples were collected by paracentesis and stored until analysis. Samples were analysed by PCR using specific primers designed to amplify herpes simplex virus 1 (HSV-1), varicella zoster virus (VZV), or human cytomegalovirus (HCMV). In a case of anterior uveitis, PCR was performed with a sample from the anterior chamber.

RESULTS

Herpesvirus DNA was amplified in 11 of 17 samples. HCVM DNA was detected in nine samples but DNA from HSV-1 and VZV were detected only once each.

CONCLUSION

These results strongly suggest that PCR could be used for a rapid complementary diagnosis of viral uveitis and retinitis. A prospective study to evaluate the PCR results, clinical evolution, and treatment is imperative to corroborate the real value of PCR in diagnosis and how it could help the clinicians' approach.

Comparison of virus isolation and various polymerase chain reaction methods in the diagnosis of mucocutaneous herpesvirus infection

We compared two polymerase chain reaction (PCR) assays (simple and multiplex) and viral isolation to detect herpes simplex virus 1 (HSV-1) and varicella-zoster virus (VZV) in 15 clinical specimens from 13 patients with mucocutaneous herpetic infections. HSV-1 or VZV DNA was detected in 13 specimens by simple PCRs (HSV-1 or VZV PCR) and in 12 specimens by multiplex PCR. On the other hand, viral isolation was positive for 9 specimens only. The PCR protocols used in this study are not only more sensitive and faster than the traditional viral isolation and conventional PCR protocols but also can distinguish rapidly HSV-1 from VZV. We propose the PCRs described here for rapid and precise identification of etiological agents of mucocutaneous herpetic infections.

PCR-based diagnosis of a case of herpetic whitlow in an AIDS patient

Herpetic infections are common complications in AIDS patients. The clinical features could be uncommon and antiviral chemotherapy is imperative. A rapid diagnosis could prevent incorrect approaches and treatment. The polymerase chain reaction is a rapid, specific and sensible method for DNA amplification and diagnosis of infectious diseases, especially viral diseases. This approach has some advantages compared with conventional diagnostic procedures. Recently we have reported a new PCR protocol to rapid diagnosis of herpetic infections with suppression of the DNA extraction step. In this paper we present a case of herpetic whitlow with rapid diagnosis by HSV-1 specific polymerase chain reaction using the referred protocol.

[Epidemiological, social, and sanitary aspects in an area of the Rio Negro, State of Amazonas, with special reference to intestinal parasites and Chagas' disease]

A cross-sectional study was carried out on the residents of one in every four dwellings in the town of Barcelos (in the northern part of the State of Amazonas, on the right bank of the Rio Negro, 490 kilometers from Manaus by river), in order to evaluate social and sanitary conditions and specific indicators for intestinal parasites and Chagas' infection. During the survey, two questionnaires were applied, a household one to evaluate social and sanitary aspects, and an individual one, for social and epidemiological evaluation of the population conditions. A conglomerate family sample of 171 dwellings was studied. From each of the 658 habitants, a sample was requested for stool examination by Lutz sedimentation and Baermann-Moraes-Coutinho techniques modified by Willcox & Coura (1989), and blood was collected in filter paper for immunofluorescence test by Camargo (1966) and Souza & Camargo (1966) methods modified by Petana & Willcox (1975). The stool examination showed 69.4% of samples with one or more parasites. Ascaris lumbricoides was predominant with 51% of positivity and Entamoeba histolytica, although surveyed by a non-specific method, was present in 19.7%. Surprisingly, 20.1% of the 658 sera samples were reactive for T. cruzi antibodies at a dilution of 1:20 and 13.7% at 1:40. There was a strong correlation between this result and the level of human contact with wild triatomines, known locally as "piasava lice", and we succeeded in isolating by xenodiagnosis one strain of T. cruzi from one patient, a sixty-one-year old man (n. 209 -1), a native of the area, with positive serology for Chagas' disease and who worked in agriculture and transporting piasava and was very familiar with "piasava lice".

Membrane fusion during secretion. A hypothesis based on electron microscope observation of Phytophthora Palmivora zoospores during encystment

Interpretation of freeze-fracture and thin-section results shows that fusion of the peripheral vesicle with the plasmalemma of a Phytophthora palmivora zoospore occurs at several discrete sites and results in the formation and expansion of a particle-free bilayer membrane diaphragm and in the appearance of a polymorphic network of membrane-bounded tunnels, the lumina of which are continuous with the cytoplasm. The outer half of the bilayer membrane diaphragm appears continuous with the outer half of the plasma membrane; the inner half of the bilayer membrane diaphragm with the inner half of the peripheral vesicle membrane; and the inner half of the plasmalemma with the outer half of the peripheral vesicle membrane. Interpretation of our results leads us to formulate a hypothesis for a sequence of several intermediate stages involved in membrane fusion. The initial fusion event is viewed as a local catastrophe (Thom, R. 1972. Stabilité Structurelle et Morphogenèse. W. A. Benjamin Inc., Reading, Mass.) involving the sudden reorganization of apposed elements of the inner half of the plasmalemma and the outer half of the peripheral vesicle membrane. Fusion of apposed components at the rim of the perimeter of fusion results in the formation of a toroid hemi-micelle which provides continuity between the inner half of the plasmalemma and the outer half of the peripheral vesicle membrane. Simultaneously, apposed components at the site of fusion may reorganize into an inverted membrane micelle. A bilayer membrane diaphragm is then formed by apposition and flowing of components form the outer half of the plasmalemma and the inner (exoplasmic) half of the peripheral vesicle membrane. The existence of large areas of membrane contact before fusion may lead to several fusion events and the formation of a polymorphic network of membrane-bound tunnels.