175 research outputs found
Paleoparasitology: Perspectives with New Techniques
Paleoparasitology is the study of parasites found in archaeological material. The development of this field of research began with histological identification of helminth eggs in mummy tissues, analysis of coprolites, and recently through molecular biology. An approach to the history of paleoparasitology is reviewed in this paper, with special reference to the studies of ancient DNA identified in archaeological material.
Paleoparasitologia: perspectivas com novas técnicas Paleoparasitologia é o estudo de parasitos encontrados em material arqueológico. O desenvolvimento deste campo da pesquisa teve início com a identificação de ovos de helmintos em tecidos mumificados, análise de coprólitos e, recentemente, através da biologia molecular. Neste artigo faz-se uma breve revisão da história da paleoparasitologia com referência especial aos estudos de ADN antigo (ancient DNA) em material arqueológic
Paleoparasitology: Perspectives with New Techniques
Paleoparasitology is the study of parasites found in archaeological material. The development of this field of research began with histological identification of helminth eggs in mummy tissues, analysis of coprolites, and recently through molecular biology. An approach to the history of paleoparasitology is reviewed in this paper, with special reference to the studies of ancient DNA identified in archaeological material.
Paleoparasitologia: perspectivas com novas técnicas Paleoparasitologia é o estudo de parasitos encontrados em material arqueológico. O desenvolvimento deste campo da pesquisa teve início com a identificação de ovos de helmintos em tecidos mumificados, análise de coprólitos e, recentemente, através da biologia molecular. Neste artigo faz-se uma breve revisão da história da paleoparasitologia com referência especial aos estudos de ADN antigo (ancient DNA) em material arqueológic
3,3′-Bithiophene
The title compound, C8H6S2, is disordered [occupancy ratio = 0.839 (2):0.161 (2)] and sits across a centre of symmetry. In the crystal, the molecules are linked by a weak C—H⋯π interaction
Anti-tumor therapy with macroencapsulated endostatin producer cells
<p>Abstract</p> <p>Background</p> <p>Theracyte is a polytetrafluoroethylene membrane macroencapsulation system designed to induce neovascularization at the tissue interface, protecting the cells from host's immune rejection, thereby circumventing the problem of limited half-life and variation in circulating levels. Endostatin is a potent inhibitor of angiogenesis and tumor growth. Continuous delivery of endostatin improves the efficacy and potency of the antitumoral therapy. The purpose of this study was to determine whether recombinant fibroblasts expressing endostatin encapsulated in Theracyte immunoisolation devices can be used for delivery of this therapeutic protein for treatment of mice bearing B16F10 melanoma and Ehrlich tumors.</p> <p>Results</p> <p>Mice were inoculated subcutaneously with melanoma (B16F10 cells) or Ehrlich tumor cells at the foot pads. Treatment began when tumor thickness had reached 0.5 mm, by subcutaneous implantation of 10<sup>7 </sup>recombinant encapsulated or non-encapsulated endostatin producer cells. Similar melanoma growth inhibition was obtained for mice treated with encapsulated or non-encapsulated endostatin-expressing cells. The treatment of mice bearing melanoma tumor with encapsulated endostatin-expressing cells was decreased by 50.0%, whereas a decrease of 56.7% in tumor thickness was obtained for mice treated with non-encapsulated cells. Treatment of Ehrlich tumor-bearing mice with non-encapsulated endostatin-expressing cells reduced tumor thickness by 52.4%, whereas lower tumor growth inhibition was obtained for mice treated with encapsulated endostatin-expressing cells: 24.2%. Encapsulated endostatin-secreting fibroblasts failed to survive until the end of the treatment. However, endostatin release from the devices to the surrounding tissues was confirmed by immunostaining. Decrease in vascular structures, functional vessels and extension of the vascular area were observed in melanoma microenvironments.</p> <p>Conclusions</p> <p>This study indicates that immunoisolation devices containing endostatin-expressing cells are effective for the inhibition of the growth of melanoma and Ehrlich tumors.</p> <p>Macroencapsulation of engineered cells is therefore a reliable platform for the refinement of innovative therapeutic strategies against tumors.</p
Padrões e mudanças no financiamento e regulação do Sistema de Saúde Brasileiro: impactos sobre as relações entre o público e privado
Synthesis and characterization of copolymers of alkyl- and azo-thiophenes: chromic properties and photoinduced birefringence
Polyazothiophene is a type of polythiophene derivative that combines the electrical and luminescent properties of polythiophenes with the photoisomerization property of azopolymers. Extensive efforts have been made to improve the properties of polyazothiophenes, such as solubility, optical, and chromic properties. We report the preparation of copolymers of an alkylthiophene (3-octylthiophene, 3-OT) and an azothiophene (2-[N-ethyl-N-[4-[(4-(4-nitrophenyl)azo]phenyl]amino]ethyl 3-thienylacetate, 3-AzoT) in different ratios as an alternative route to improve these properties. The azosubstituted monomer contents in these copolymers were 6, 9, 12, and 51% (in mol), as evaluated by elemental analysis. Their chemical structures were confirmed by FTIR and 1H-NMR. HPSEC and thermal analysis were used to characterize the polymers. The presence of thermochromic and solvatochromic properties was demonstrated by UV-Vis spectroscopy. Optically induced birefringence was detected only in polymers with 12 and 51 mol % of azo-units. The introduction of different ratios of the azothiophene in the copolymer alters the polymer solubility and emissive properties. The results indicate that the polyazothiophene copolymers presented are promising active layers for optical devices and sensor
Granulomatous-like immune reaction and hepatic fibrosis induced by Schistosoma haematobium immature worms
Golden hamsters were inoculated with Schistosoma haematobium cercariae to examine histological lesions at different
time points over an 18 month period of infection. Hamsters were sacrificed 26 weeks and 82 weeks after inoculation.
The parasite was found in the blood and in the liver of infected animals as was expected, but we found exclusively male
worms, no female worms nor eggs. Interestingly we observed unexpected hepatic lesions induced by S. haematobium
immature male worms alone in the golden hamster, characteristic of schistosome eggs. Samples from liver, kidneys,
lungs, bladder and gastrointestinal tract were collected during necropsy to evaluate injuries induced by S. haematobium.
Notably we observed hepatitis in the liver of infected hamsters, no lesions were found in other organs. We also found liver
fibrosis in infected hamsters. This study provides further experimental evidence for the role that schistosome worms,
and their derived antigens, may play in the pathology of the infection and modulation of liver chronic inflammation in
the murine model of schistosomiasis
One-Step Isolation of Monoterpene Indole Alkaloids from Psychotria Leiocarpa Leaves and Their Antiviral Activity on Dengue Virus Type-2
The leaf MeOH extract of Psychotria leiocarpa (Rubiaceae) showed in vitro non-cytotoxic and anti-dengue virus serotype 2 (DENV2) activity in human hepatocarcinoma cell lineage (HepG2). A one-step and cost-effective reversed-phase solid-phase extraction method based on high-performance liquid chromatography (HPLC) parameters allowed the isolation, directly from this bioactive extract, of the monoterpene indole alkaloids: N-glucopyranosyl vincosamide (1), vincosamide (2) and strictosidinic acid (3). The chemical structures were characterized based on 1D and 2D nuclear magnetic resonance (NMR), UV and high-resolution mass spectra (HRMS). The methodology has also allowed yielding a polyphenolic-rich fraction that was analyzed by high-performance liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI-MS/MS) revealing two fiavonol triglycosides (4, 5) and three caffeoylquinic acid isomers (6-8). Compound 3 is reported for the first time in P leiocarpa and all the phenolic compounds (4-8) are described for the first time in the genus Psychotria. Compounds 1-3 showed to be non-cytotoxic and anti-dengue active towards DENV2, highlighting vincosamide (2).This work was supported by Fundacao Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro (FAPERJ), processes No. E-26/111.373/2014 and E-26/203.225/2017. DGL and JOC thank Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES), finance code 001, for their fellowships. TW thanks both CAPES and FAPERJ for his fellowships. The authors thank the NMR Lab of the Instituto de Pesquisas em Produtos Naturais, Universidade Federal do Rio de Janeiro for the NMR spectra and MSc Matheus Oliveira, Dr Marcelo M. Pereira and Dr Denise Freire for their support. Technical and staff support provided by SGIker (UPV/EHU, MICINN, GV/EJ, ESF) is also gratefully acknowledged
Methicillin-resistant Staphylococcus aureus (MRSA) carriage in a dermatology unit
OBJECTIVE: The aim of this study was to characterize Staphylococcus aureus (MRSA) carriage in a dermatology unit. METHODS: This was a prospective and descriptive study. Over the course of 26 weeks, surveillance cultures were collected weekly from the anterior nares and skin of all patients hospitalized in a 20-bed dermatology unit of a tertiary-care hospital. Samples from healthcare workers (HCWS) were cultured at the beginning and end of the study. Colonized patients were put under contact precautions, and basic infection control measures were enforced. Staphylococcus aureus colonization pressure was determined monthly. Colonized and non-colonized patients were compared, and isolates were evaluated for antimicrobial susceptibility, SCCmec type, virulence factors, and type. RESULTS: Of the 142 patients evaluated, 64 (45%) were colonized by MRSA (39% hospital acquired; 25% community acquired; 36% indeterminate). Despite isolation precautions, hospital-acquired Staphylococcus aureus occurred in addition to the continuous entry of Staphylococcus aureus from the community. Colonization pressure increased from 13% to 59%, and pemphigus and other bullous diseases were associated with MRSA colonization. Eleven out of 71 HCWs (15%) were Staphylococcus aureus carriers, although only one worker carried a persistent clone. Of the hospital-acquired MRSA cases, 14/28 (50%) were SCCmec type IV (3 PFGE types), 13 were SCCmec type III (46%), and one had an indeterminate type. These types were also present among the community-acquired Staphylococcus aureus isolates. SSCmec type IV isolates were shown to be more susceptible than type III isolates. There were two cases of bloodstream infection, and the pvl and tst virulence genes were absent from all isolates. CONCLUSIONS: Dermatology patients were colonized by community- and hospital-acquired Staphylococcus aureus. Half of the nosocomial Staphylococcus aureus isolates were SCCmec type IV. Despite the identification of colonized patients and the subsequent contact precautions and room placement, Staphylococcus aureus colonization continued to occur, and colonization pressure increased. Pemphigus and other bullous diseases were associated with Staphylococcus aureus
- …