The tropical peatlands of southern Brazil are essential for the maintenance of the Atlantic Rain Forest, one of the 25 hotspots of biodiversity in the world. Although diazotrophic micro‐organisms are ...essential for the maintenance of this nitrogen limited ecosystem, so far studies have focused only on micro‐organisms involved in the carbon cycle. In this work, peat samples were collected from three tropical peatland regions during dry and rainy seasons and their chemical and microbial characteristics were evaluated. Our results showed that the structure of the diazotrophic communities in the Brazilian tropical peatlands differs in the evaluated seasons. The abundance of the genus Bradyrhizobium showed to be affected by rainfall and peat pH. Despite the shifts of the nitrogen‐fixing population in the tropical peatland caused by seasonality it showed to be constantly dominated by α‐Proteobacteria followed by Cyanobacteria. In addition, more than 50% of nifH gene sequences have not been classified, indicating the necessity for more studies in tropical peatland, since the reduction of N supply in the peatlands stimulates the recalcitrant organic matter decomposition performed by peatland micro‐organisms, influencing the C stock.
Significance and Impact of the Study: This manuscript reports the first ecological study of tropical peatlands diazotrophic communities from the Brazilian Atlantic Rain Forest, one of the world's largest biodiversity hotspots. Based on culturing and culture‐independent approaches, our results showed alterations in the structure of the diazotrophic communities in different seasons. The genus Bradyrhizobium abundance was affected by rainfall and peat pH. In addition, the great number of unclassified nitrogen‐fixing bacteria indicated the need for additional studies to guide future mitigation actions, since the reduction of N supply in the peatlands stimulates the recalcitrant organic matter decomposition performed by peatland micro‐organisms, influencing the C stock.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Aim
This study aimed to evaluate the association of toll‐like receptor (TLR) inflammatory cascade with the development of diabetic kidney disease (DKD) in children and adolescents with type 1 ...diabetes (T1D).
Methods
A total of 49 T1D patients and 49 normoglycaemic (NG) subjects aged 5–20 years old were recruited. TLR2, TLR4, MYD88, NFKB, MCP1/CCL2 and IL18 mRNA expressions were measured in peripheral blood mononuclear cells by reverse transcription–quantitative polymerase chain reaction. Fasting glucose, glycated haemoglobin, serum urea, serum creatinine and urinary albumin‐to‐creatinine ratio (ACR) were determined.
Results
The mRNA expressions of TLR2, TLR4, MYD88 and NFKB were significantly increased in the T1D group compared with the NG group. The mRNA expression levels of MCP1/CCL2 and IL18 were higher in 21 T1D patients (42.9%) (average of MCP1/CCL2: 6.6‐fold and IL18: 5.8‐fold) than in NG patients. Furthermore, ACR was increased in the T1D group compared with the NG group.
Conclusion
The increased mRNA expression of TLR2, TLR4, MYD88, NFKB, MCP1/CCL2 and IL18 favours the development of an inflammatory process that may lead to a decline in renal function and consequently DKD in children and adolescents with T1D. This suggests that these genes are early mediators of onset DKD since the beginning of the lives of the paediatric T1D patients.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Photonic interference is a key quantum resource for optical quantum computation, and in particular for so-called boson sampling devices. In interferometers with certain symmetries, genuine ...multiphoton quantum interference effectively suppresses certain sets of events, as in the original Hong-Ou-Mandel effect. Recently, it was shown that some classical and semi-classical models could be ruled out by identifying such suppressions in Fourier interferometers. Here we propose a suppression law suitable for random-input experiments in multimode Sylvester interferometers, and verify it experimentally using 4- and 8-mode integrated interferometers. The observed suppression occurs for a much larger fraction of input-output combinations than what is observed in Fourier interferometers of the same size, and could be relevant to certification of boson sampling machines and other experiments relying on bosonic interference, such as quantum simulation and quantum metrology.
Background
Although anorectal transplantation is a challenging procedure, it is a promising option for patients who have completely lost anorectal function or in whom it failed to develop, as in ...congenital malformations. The paucity of animal models with which to test functional outcomes was addressed in this study of anorectal manometry in rats.
Methods
Wistar rats were assigned randomly to four groups: orthotopic anorectal transplantation, heterotopic transplantation, sham operation, or normal control. Bodyweight and anal pressure were measured immediately before and after operation, and on postoperative days 7 and 14. ANOVA and Tukey's test were used to compare results for bodyweight, anal manometry and length of procedure.
Results
Immediately after the procedure, mean(s.d.) anal pressure in the orthotopic group (n = 13) dropped from 31·4(13·1) to 1·6(13·1) cmH2O (P < 0·001 versus both sham operation (n = 13) and normal control (n = 15)), with partial recovery on postoperative day 7 (14·9(13·9) cmH2O) (P = 0·009 versus normal control) and complete recovery on day 14 (23·7(12·2) cmH2O). Heterotopic rats (n = 14) demonstrated partial functional recovery: mean(s.d.) anal pressure was 26·9(10·9) cmH2O before operation and 8·6(6·8) cmH2O on postoperative day 14 (P < 0·001 versus both sham and normal control).
Conclusion
Orthotopic anorectal transplantation may result in better functional outcomes than heterotopic procedures.
Surgical relevance
Patients with a permanent colostomy have limited continence. Treatment options are available, but anorectal transplantation may offer hope. Some experimental studies have been conducted, but available data are currently insufficient to translate into a clinical option. This paper details functional outcomes in a rat model of anorectal autotransplantation. It represents a step in the translational research that may lead to restoration of anorectal function in patients who have lost or have failed to develop it.
Technically possible in animal models
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Duguetia pycnastera Sandwith (Annonaceae) is a tropical tree that can be found in the Guyanas, Bolivia, Venezuela, and Brazil. In Brazil, it is popularly known as “ata”, “envira”, “envira-preta”, and ...“envira-surucucu”. In the present work, we investigated the in vitro and in vivo HepG2 cell growth inhibition capacity of D. pycnastera leaf essential oil (EO). The chemical composition of the EO was determined by GC−MS and GC−FID analyses. The alamar blue assay was used to examine the in vitro cytotoxicity of EO in cancer cell lines and non-cancerous cells. In EO-treated HepG2 cells, DNA fragmentation was measured by flow cytometry. The in vivo antitumor activity of the EO was assessed in C.B-17 SCID mice xenografted with HepG2 cells treated with the EO at a dosage of 40 mg/kg. Chemical composition analysis displayed the sesquiterpenes α-gurjunene (26.83%), bicyclogermacrene (24.90%), germacrene D (15.35%), and spathulenol (12.97%) as the main EO constituents. The EO exhibited cytotoxicity, with IC50 values ranging from 3.28 to 39.39 μg/mL in the cancer cell lines SCC4 and CAL27, respectively. The cytotoxic activity of the EO in non-cancerous cells revealed IC50 values of 16.57, 21.28, and >50 μg/mL for MRC-5, PBMC, and BJ cells, respectively. An increase of the fragmented DNA content was observed in EO-treated HepG2 cells. In vivo, EO displayed tumor mass inhibition activity by 47.76%. These findings imply that D. pycnastera leaf EO may have anti-liver cancer properties.
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The successful establishment of HIV-1 infection is related to inflammasome blocking or inactivation, which can result in the viral evasion of the immune responses and formation of reservoirs in ...several tissues. In this sense, we aimed to evaluate the viral and cellular mechanisms activated during HIV-1 infection in human primary macrophages that allow an effective viral replication in these cells. We found that resting HIV-1-infected macrophages, but not those activated in classical or alternative patterns, released IL-1β and other pro-inflammatory cytokines, and showed increased CXCL10 expression, without changes in the NLRP3, AIM2 or RIG-I inflammasome pathways. Also, similar levels of Casp-1, phosphorylated NF-κB (p65) and NLRP3 proteins were found in uninfected and HIV-1-infected macrophages. Likewise, no alterations were detected in ASC specks released in the culture supernatant after HIV-1 infection, suggesting that macrophages remain viable after infection. Using in silico prediction studies, we found that the HIV-1 proteins Gag and Vpr interact with several host proteins. Comparable levels of trans-LTB4 were found in the supernatants of uninfected and HIV-1-infected macrophages, whereas ROS production was impaired in infected cells, which was not reversed after the PMA stimulus. Immunofluorescence analysis showed structural alterations in the mitochondrial architecture and an increase of BIM in the cytoplasm of infected cells. Our data suggest that HIV-1 proteins Gag and Vpr, through interacting with cellular proteins in the early steps of infection, preclude the inflammasome activation and the development of effective immune responses, thus allowing the establishment of the infection.
•HIV infects macrophages from several tissues and can harbor viral proliferation, representing an important reservoir.•The macrophage inflammasome is activated during viral recognition to control the infection and may result in cellular death.•Resting HIV-1-infected macrophages release IL-1b and increased CXCL10 expression, without changing the inflammasome pathways.•Our results suggest that proteins HIV-1 Gag and Vpr may subvert the inflammasome activation and allow viral replication.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Guatteria olivacea R. E. Fries (synonym Guatteria punctata (Aubl.) R.A. Howard) is a tree of 10–27 m tall popularly known as “envira-bobó”, “envira-fofa”, “envireira”, “embira”, “embira-branca”, ...“embira-preta”, envira-branca”, and “envira-preta”, which can be found in the Brazilian Amazon biome. In this study, we evaluated the cytotoxic and antitumor effects of the essential oil (EO) obtained from the leaves of G. olivacea against liver cancer using HepG2 cells as a model. EO was obtained using a hydrodistillation Clevenger-type apparatus and was qualitatively and quantitatively characterized using GC–MS and GC–FID, respectively. The alamar blue assay was used to assess the cytotoxic potential of EO in a panel of human cancer cell lines and human non-cancerous cells. In HepG2 cells treated with EO, YO-PRO-1/propidium iodide staining, cell cycle distribution, and reactive oxygen species (ROS) were examined. In C.B-17 SCID mice with HepG2 cell xenografts, the efficacy of the EO (20 and 40 mg/kg) was tested in vivo. GC–MS and GC–FID analyses showed germacrene D (17.65%), 1-epi-cubenol (13.21%), caryophyllene oxide (12.03%), spathulenol (11.26%), (E)-caryophyllene (7.26%), bicyclogermacrene (5.87%), and δ-elemene (4.95%) as the major constituents of G. olivacea leaf EO. In vitro cytotoxicity of EO was observed, including anti-liver cancer action with an IC50 value of 30.82 μg/mL for HepG2 cells. In HepG2 cells, EO treatment increased apoptotic cells and DNA fragmentation, without changes in ROS levels. Furthermore, the EO inhibited tumor mass in vivo by 32.8–57.9%. These findings suggest that G. olivacea leaf EO has anti-liver cancer potential.
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The increase in antibiotic resistance and the emergence of new bacterial infections have intensified the research for natural products from plants with associated therapy. This study aimed to verify ...the antibacterial and antioxidant activity of crude extracts of the genus
species, being the first report on the modulation of aminoglycosides antibiotic activity by
extracts. The chemical composition was obtained by chemical prospecting and High-Performance Liquid Chromatography with diode arrangement detector (HPLC/DAD). The antibacterial activities of the extracts alone or in association with aminoglycosides were analyzed using the microdilution test. The antioxidant activity was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging. The phytochemical prospection allowed the flavonoids, saponins, tannins and triterpenoids to be identified. Quercetin, rutin, gallic acid, chlorogenic acid, caffeic acid, catechin, kaempferol, glycosylated kaempferol, quercitrin, and isoquercitrin were identified and quantified. The principal component analysis (PCA) observed the influence of flavonoids and phenolic acids from
species on studied activities. Phytochemical tests with the extracts indicated, especially, the presence of flavonoids, confirmed by quantitative analysis by HPLC. The results revealed antibacterial activities, and synergistic effects combined with aminoglycosides, as well as antioxidant potential, especially for
species, with IC
of 32.21 µg/mL. Multivariate analyzes show that the inclusion of data from the antioxidant and antibacterial activity suggests that the antioxidant effect of these species presents a significant contribution to the synergistic effect of phytoconstituents, especially based on the flavonoid contents. The results of this study suggest the antibacterial activity of
extracts, as well as their potential in modifying the resistance of the analyzed aminoglycosides.
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The evolution of bosons undergoing arbitrary linear unitary transformations quickly becomes hard to predict using classical computers as we increase the number of particles and modes. Photons ...propagating in a multiport interferometer naturally solve this so-called boson sampling problem, thereby motivating the development of technologies that enable precise control of multiphoton interference in large interferometers. Here, we use novel three-dimensional manufacturing techniques to achieve simultaneous control of all the parameters describing an arbitrary interferometer. We implement a small instance of the boson sampling problem by studying three-photon interference in a five-mode integrated interferometer, confirming the quantum-mechanical predictions. Scaled-up versions of this set-up are a promising way to demonstrate the computational advantage of quantum systems over classical computers. The possibility of implementing arbitrary linear-optical interferometers may also find applications in high-precision measurements and quantum communication.
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