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1.
Foods ; 13(9)2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38731724

ABSTRACT

This study aimed to evaluate the influence of films based on chitosan and rosemary extract on the physicochemical, microbiological, and oxidative characteristics of beef. Refrigerated steaks of Longissimus dorsi were distributed in a factorial arrangement (4 × 4) into four treatments consisting of four edible films (control; chitosan; chitosan + 4% rosemary extract; and chitosan + 8% rosemary extract) and four days of aging (0, 2, 4, and 8 days). Incorporating 4% or 8% rosemary extract into the chitosan film improved the characteristics of the films in terms of moisture absorption and elasticity. The edible coatings with chitosan and rosemary extract and the different days of aging increased the tenderness and decreased the lipid oxidation of beef. In addition, the chitosan films containing rosemary extract increased the water-holding capacity and decreased the cooking losses of beef. The films containing 4% and 8% rosemary extract decreased the development of mesophilic and psychrotrophic bacteria and Staphylococcus ssp. in beef. We recommend incorporating 4% rosemary extract into chitosan-based coatings to preserve the quality of refrigerated beef.

2.
Ultramicroscopy ; 209: 112862, 2020 02.
Article in English | MEDLINE | ID: mdl-31707231

ABSTRACT

Atomic force microscopy (AFM) was used in this work to investigate the ultrastructural and mechanical characteristics of Haemonchus contortus, the major gastrointestinal nematode that infects small ruminants worldwide. The biophysical characterization of this species is extremely important in order to reveal mechanisms of action of drugs and to classify its ultrastructure and biomechanical properties. High-resolution topographic images by AFM as well as data on biomechanical properties of cuticles were obtained at different stages of H. contortus. The results reveal details of the mechanical and structural properties of this nematode never observed before for nematodes parasite with other microscope techniques. Qualitative and quantitative reductions in the elasticity of the larvae stage egg were compared with those of the morulae stage, and the increased adhesion of unsheathed L3 were compared with the same stage of sheathed larvae. The results presented here open possibilities for understanding the mechanisms of drug and biomolecular actions that can be used to control infections caused by H. contortus.


Subject(s)
Haemonchus/ultrastructure , Microscopy, Atomic Force/methods , Animals , Biomechanical Phenomena , Biophysics , Female , Haemonchus/growth & development , Larva , Life Cycle Stages , Sheep
3.
Drug Deliv ; 25(1): 1585-1594, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30044149

ABSTRACT

Voriconazole (VCZ), a triazole with a large spectrum of action is one of the most recommended antifungal agents as the first line therapy against several clinically important systemic fungal infections, including those by Candida albicans. This antifungal has moderate water solubility and exhibits a nonlinear pharmacokinetic (PK) profile. By entrapping VCZ into liposomes, it is possible to circumvent certain downsides of the currently available product such as a reduction in the rate of its metabolization into an inactive form, avoidance of the toxicity of the sulfobutyl ether-beta-cyclodextrin (SBECD), vehicle used to increase its solubility. PKs and biodistribution of VCZ modified by encapsulation into liposomes resulted in improved antifungal activity, due to increased specificity and tissue penetration. In this work, liposomal VCZ resulted in AUC0-24/MIC ratio of 53.51 ± 11.12, whereas VFEND® resulted in a 2.5-fold lower AUC0-24/MIC ratio (21.51 ± 2.88), indicating favorable antimicrobial systemic activity. VCZ accumulation in the liver and kidneys was significantly higher when the liposomal form was used. Protection of the drug from biological degradation and reduced rate of metabolism leads to a 30% reduction of AUC of the inactive metabolite voriconazole-N-oxide (VNO) when the liposomal drug was administered. Liposomal VCZ presents an alternative therapeutic platform, leading to a safe and effective treatment against systemic fungal infections.


Subject(s)
Antifungal Agents/administration & dosage , Antifungal Agents/pharmacokinetics , Drug Delivery Systems/methods , Voriconazole/administration & dosage , Voriconazole/pharmacokinetics , Administration, Intravenous , Animals , Antifungal Agents/chemistry , Aspergillus/drug effects , Aspergillus/physiology , Candida albicans/drug effects , Candida albicans/physiology , Candidiasis/drug therapy , Candidiasis/metabolism , Drug Compounding , Humans , Liposomes , Male , Mice, Inbred BALB C , Microbial Sensitivity Tests/methods , Tissue Distribution/drug effects , Tissue Distribution/physiology , Voriconazole/chemistry
4.
Mycoses ; 60(1): 59-65, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27625302

ABSTRACT

Histoplasmosis is a systemic mycosis that is considered an important public health problem. In this work, we performed a descriptive, observational, cross-sectional and retrospective study with a secondary data analysis of medical records from 2000 to 2012 at a tertiary hospital. The study sample consisted of 275 patients with laboratory-confirmed Disseminated Histoplasmosis (DH)/AIDS. The results showed that the prevalence of DH associated with AIDS was 4.4%. The majority of patients were young adult men with fever in 84.2%, cough in 63.4%, weight loss in 63.1%, diarrhoea in 44.8% and skin manifestations in 27.6% of patients. In the overall cohort, the CD4 counts were low, but not significantly different in survivors and non-survivors. Higher levels of urea and lower levels of haemoglobin and platelets were observed in non-survivor patients (<.05). The global lethality was 71.3% (196/275). The results with high prevalence and lethality highlight the need to adopt measures to facilitate early diagnosis, proper treatment and improved prognosis.


Subject(s)
Acquired Immunodeficiency Syndrome/complications , Histoplasmosis/epidemiology , Opportunistic Infections/epidemiology , Acquired Immunodeficiency Syndrome/epidemiology , Acquired Immunodeficiency Syndrome/mortality , Adolescent , Adult , Aged , Antifungal Agents/therapeutic use , Brazil/epidemiology , CD4 Lymphocyte Count , Child , Cohort Studies , Cross-Sectional Studies , Female , Hemoglobins/analysis , Histoplasmosis/drug therapy , Histoplasmosis/mortality , Humans , Male , Medical Records , Middle Aged , Opportunistic Infections/drug therapy , Opportunistic Infections/mortality , Platelet Count , Prevalence , Retrospective Studies , Tertiary Care Centers/statistics & numerical data , Urea/analysis , Young Adult
5.
Int J Biol Markers ; 31(1): e38-43, 2016 Feb 28.
Article in English | MEDLINE | ID: mdl-26349667

ABSTRACT

PURPOSE: The use of trastuzumab (Herceptin) to target HER2 has been applied in breast carcinoma and gastric carcinoma (GC). Previous studies have tested trastuzumab's effectiveness by assessing HER2 expression or HER2 amplification by means of immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH). In this work we aimed to evaluate automated FISH and IHC technologies for HER2 detection in GC biopsies to be used in routine pathology practice. METHODS: The study used an Oracle HER2 IHC System and an LSI HER2/CEP17 Dual Probe on an automated Bond system (Leica Microsystems). One hundred GC biopsies were evaluated including 44 intestinal type, 38 diffuse type and 18 indeterminate type according to Lauren's classification. RESULTS: The overall concordance rate between the automated FISH and IHC methods was 94% (κ = 0.87), as 6 samples were scored as equivocal (4 in IHC and 2 in FISH). Moreover, HER2 positivity was significantly different between the 3 types of GC (p<0.05), being more frequent in intestinal-type GC (23%) than in the other 2 histological types (5% and 0%). Finally, the HER2/CEP17 FISH ratio was significantly different (p<0.01) between disomic and polysomic samples, being higher in polysomic samples (mean 1.633 ± 0.509) than in disomic samples (mean 1.231 ± 0.675). CONCLUSIONS: Automated HER2 testing of GC biopsies using the Leica Bond system was useful and efficient. This method allowed us to improve normal routine procedures, minimizing time and costs as well as handling and observation errors.


Subject(s)
Biomarkers, Tumor/biosynthesis , Carcinoma/diagnosis , Receptor, ErbB-2/biosynthesis , Stomach Neoplasms/diagnosis , Biomarkers, Tumor/genetics , Biopsy , Carcinoma/genetics , Carcinoma/pathology , Gene Expression Regulation, Neoplastic/drug effects , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Receptor, ErbB-2/genetics , Stomach Neoplasms/genetics , Stomach Neoplasms/pathology , Trastuzumab/therapeutic use
6.
Biomed Res Int ; 2014: 305239, 2014.
Article in English | MEDLINE | ID: mdl-24812611

ABSTRACT

At present, noncoding small RNAs are recognized as key players in novel forms of posttranscriptional gene regulation in most eukaryotes. However, canonical small RNA pathways seem to be lost or excessively simplified in some unicellular organisms including Trypanosoma cruzi which lack functional RNAi pathways. Recently, we reported the presence of alternate small RNA pathways in T. cruzi mainly represented by homogeneous populations of tRNA- and rRNA-derived small RNAs, which are secreted to the extracellular medium included in extracellular vesicles. Extracellular vesicle cargo could be delivered to other parasites and to mammalian susceptible cells promoting metacyclogenesis and conferring susceptibility to infection, respectively. Here we analyzed the changes in gene expression of host HeLa cells induced by extracellular vesicles from T. cruzi. As assessed by microarray assays a large set of genes in HeLa cells were differentially expressed upon incorporation of T. cruzi-derived extracellular vesicles. The elicited response modified mainly host cell cytoskeleton, extracellular matrix, and immune responses pathways. Some genes were also modified by the most abundant tRNA-derived small RNAs included in extracellular vesicles. These data suggest that microvesicles secreted by T. cruzi could be relevant players in early events of the T. cruzi host cell interplay.


Subject(s)
Cytoplasmic Vesicles/metabolism , Gene Expression Regulation , Host-Parasite Interactions , Mammals/parasitology , RNA, Transfer/metabolism , Trypanosoma cruzi/genetics , Animals , Cytoskeleton/metabolism , Extracellular Matrix/genetics , Extracellular Space/metabolism , Gene Expression Profiling , HeLa Cells , Humans , Immunity/genetics , Kinetics , Oligonucleotide Array Sequence Analysis , Time Factors , Transfection
7.
Parasitol Res ; 113(1): 285-304, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24241124

ABSTRACT

The protozoan parasite Trypanosoma cruzi has a complex life cycle characterized by intracellular and extracellular forms alternating between invertebrate and mammals. To cope with these changing environments, T. cruzi undergoes rapid changes in gene expression, which are achieved essentially at the posttranscriptional level. At present, expanding families of small RNAs are recognized as key players in novel forms of posttranscriptional gene regulation in most eukaryotes. However, T. cruzi lacks canonical small RNA pathways. In a recent work, we reported the presence of alternate small RNA pathways in T. cruzi mainly represented by a homogeneous population of tRNA-derived small RNAs (tsRNAs). In T. cruzi epimastigotes submitted to nutrient starvation, tsRNAs colocalized with an argonaute protein distinctive of trypanosomatids (TcPIWI-tryp) and were recruited to particular cytoplasmic granules. Using epifluorescence and electronic microscopy, we observed that tsRNAs and the TcPIWI-tryp protein were recruited mainly to reservosomes and other intracellular vesicles including endosome-like vesicles and vesicular structures resembling the Golgi complex. These data suggested that, in T. cruzi, tsRNA biogenesis is probably part of endocytic/exocytic routes. We also demonstrated that epimastigotes submitted to nutrient starvation shed high levels of vesicles to the extracellular medium, which carry small tRNAs and TcPIWI-tryp proteins as cargo. At least a fraction of extracellular vesicle cargo was transferred between parasites and to mammalian susceptible cells. Our data afford experimental evidence, indicating that extracellular vesicles shed by T. cruzi promote not only life cycle transition of epimastigotes to trypomastigote forms but also infection susceptibility of mammalian cells.


Subject(s)
Cytoplasmic Vesicles/parasitology , Life Cycle Stages/physiology , RNA, Protozoan/metabolism , Trypanosoma cruzi/physiology , Animals , Chlorocebus aethiops , Endosomes/parasitology , Golgi Apparatus/parasitology , Humans , K562 Cells , Microscopy, Electron, Transmission , RNA, Transfer/metabolism , Trypanosoma cruzi/genetics , Trypanosoma cruzi/ultrastructure , Vero Cells
8.
Biopolymers ; 98(4): 322-31, 2012.
Article in English | MEDLINE | ID: mdl-23193596

ABSTRACT

The antimicrobial peptides (AMPs) are evolutionarily ancient molecules that act as components of the innate immune system. Recently, it was demonstrated that a single AMP can perform various functions; this ability is known as "peptide promiscuity." However, little is known about promiscuity in plant AMPs without disulfide bonds. This study was carried out to evaluate the promiscuity of Cn-AMP1: a promising disulfide-free plant peptide with reduced size and cationic and hydrophobic properties. Its activity against human pathogenic bacteria and fungal pathogens, as well as its in vitro immunostimulatory activity and effects on cancerous and healthy mammalian cell proliferation were studied here. Cn-AMP1 exerts antimicrobial effects against Gram-positive bacteria, Gram-negative bacteria, and fungi. Moreover, tumor cell viability activity in Caco-2 cells, as well as immunostimulatory activity by evaluating upregulated inflammatory-cytokine secretion by monocytes was also positively observed. Cn-AMP1 does not exhibit a well-defined conformation in aqueous solution and probably undergoes a 3(10)-helix transition in hydrophobic environments. The experimental results support the promiscuous activity of Cn-AMP1, presenting a wide range of activities, including antibacterial, antifungal, and immunostimulatory activity. In the future, Cn-AMP1 should be used in the development of novel biopharmaceuticals, mainly due to its reduced size and broad spectrum of activity.


Subject(s)
Anti-Infective Agents/pharmacology , Peptides/pharmacology , Adjuvants, Immunologic/chemistry , Adjuvants, Immunologic/pharmacology , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/chemistry , Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Humans , Peptides/chemistry
9.
PLoS One ; 7(10): e47047, 2012.
Article in English | MEDLINE | ID: mdl-23056574

ABSTRACT

Recently, defense peptides that are able to act against several targets have been characterized. The present work focuses on structural and functional evaluation of the peptide analogue Pa-MAP, previously isolated as an antifreeze peptide from Pleuronectes americanus. Pa-MAP showed activities against different targets such as tumoral cells in culture (CACO-2, MCF-7 and HCT-116), bacteria (Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 25923), viruses (HSV-1 and HSV-2) and fungi (Candida parapsilosis ATCC 22019, Trichophyton mentagrophytes (28d&E) and T. rubrum (327)). This peptide did not show toxicity against mammalian cells such as erythrocytes, Vero and RAW 264.7 cells. Molecular mechanism of action was related to hydrophobic residues, since only the terminal amino group is charged at pH 7 as confirmed by potentiometric titration. In order to shed some light on its structure-function relations, in vitro and in silico assays were carried out using circular dichroism and molecular dynamics. Furthermore, Pa-MAP showed partial unfolding of the peptide changes in a wide pH (3 to 11) and temperature (25 to 95°C) ranges, although it might not reach complete unfolding at 95°C, suggesting a high conformational stability. This peptide also showed a conformational transition with a partial α-helical fold in water and a full α-helical core in SDS and TFE environments. These results were corroborated by spectral data measured at 222 nm and by 50 ns dynamic simulation. In conclusion, data reported here show that Pa-MAP is a potential candidate for drug design against pathogenic microorganisms due to its structural stability and wide activity against a range of targets.


Subject(s)
Alanine/chemistry , Flounder/metabolism , Peptides/chemistry , Peptides/pharmacology , Animals , Caco-2 Cells , Candida/drug effects , Cell Line , Erythrocytes/drug effects , HCT116 Cells , Humans , Staphylococcus aureus/drug effects , Trichophyton/drug effects
10.
Biochimie ; 94(4): 968-74, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22210491

ABSTRACT

Antimicrobial peptides have been found in mollusks and other sea animals. In this report, a crude extract of the marine snail Cenchritis muricatus was evaluated against human pathogens responsible for multiple deleterious effects and diseases. A peptide of 1485.26 Da was purified by reversed-phase HPLC and functionally characterized. This trypsinized peptide was sequenced by MS/MS technology, and a sequence (SRSELIVHQR), named Cm-p1 was recovered, chemically synthesized and functionally characterized. This peptide demonstrated the capacity to prevent the development of yeasts and filamentous fungi. Otherwise, Cm-p1 displayed no toxic effects against mammalian cells. Molecular modeling analyses showed that this peptide possible forms a single hydrophilic α-helix and the probable cationic residue involved in antifungal activity action is proposed. The data reported here demonstrate the importance of sea animals peptide discovery for biotechnological tools development that could be useful in solving human health and agribusiness problems.


Subject(s)
Antifungal Agents/isolation & purification , Peptide Fragments/isolation & purification , Amino Acid Sequence , Animals , Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Cell Survival/drug effects , Cells, Cultured , Chromatography, Reverse-Phase , Erythrocytes , Fungi/drug effects , Humans , Hydrophobic and Hydrophilic Interactions , Mice , Microbial Sensitivity Tests , Models, Molecular , Molecular Sequence Data , Peptide Fragments/chemistry , Peptide Fragments/pharmacology , Protein Structure, Secondary , Sequence Analysis, Protein , Snails , Surface Properties
11.
Phytochemistry ; 74: 166-72, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22137037

ABSTRACT

A phytochemical study of the ethyl acetate extract of the roots and adventitious roots of Spirotropis longifolia, a monodominant tree species of the Guianan rainforest, has allowed the isolation of three compounds: 2-hydroxy-8,9-methylenedioxy-2',2'-dimethylpyrano-[5',6':4,3]-6a-prenyl-[6aS,11aS]-pterocarpan (spirotropin A), 2-hydroxy-8,9-methylenedioxy-2',2'-dimethyl-3',4'-dihydropyrano-[5',6':4,3]-6a-prenyl-[6aS,11aS]-pterocarpan (spirotropin B), and 5,7-dihydroxy-6,8-diprenyl-2'''',2''''-dimethylpyrano[5'''',6'''': 3',4']-isoflavone (spirotropone). In addition, 10 known compounds, trans-oxyresveratrol, trans-resveratrol, piceatannol, daidzein, genistein, isoprunetin, lupeol, latifolol, gnetin D and gnetin E, were also isolated. These compounds were evaluated for their antifungal activity and their cytotoxicity, and their structures were established by 1D and 2D NMR, HRMS, CD and optical rotation measurements.


Subject(s)
Antifungal Agents/pharmacology , Fabaceae/chemistry , Fungi/drug effects , Isoflavones/pharmacology , Plant Extracts/pharmacology , Antifungal Agents/chemistry , Antifungal Agents/isolation & purification , Fabaceae/metabolism , Humans , Isoflavones/chemistry , Isoflavones/isolation & purification , Molecular Structure , Plant Extracts/chemistry , Plant Roots
12.
Clinics (Sao Paulo) ; 66(8): 1335-40, 2011.
Article in English | MEDLINE | ID: mdl-21915480

ABSTRACT

OBJECTIVE: To evaluate the outcomes of acute myeloid leukemia patients who were older than 60 years of age at the time of diagnosis following the implementation of a treatment algorithm based on age, performance status, and cytogenetic results. METHODS: We retrospectively compared the results of 31 elderly acute myeloid leukemia patients (median age of 74 years) who were treated according to the new algorithm. RESULTS: Fifteen patients with a good performance status and no unfavorable karyotypes were treated with either intensive cytotoxic chemotherapy (<70 years, nine cases) or adapted etoposide, 6-thioguanine and idarubicine (>70 years, six cases); 16 cases with a poor performance status or unfavorable cytogenetics received supportive care only. Six patients achieved a complete remission and two achieved a partial remission after chemotherapy. There were three toxic deaths during induction, two in the adapted etoposide, 6-thioguanine and idarubicine group and one in the intensive cytotoxic chemotherapy group. The overall median survival time was 2.96 months, 1.3 months in the supportive care group, and 4.6 months in the treatment group. CONCLUSIONS: Our results illustrate the importance of treatment guidelines adapted to local resources in an attempt to improve the survival of elderly acute myeloid leukemia patients in developing countries.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Leukemia, Myeloid, Acute/drug therapy , Aged , Aged, 80 and over , Algorithms , Brazil , Cytogenetic Analysis , Etoposide/administration & dosage , Female , Hospitals, University , Humans , Idarubicin/administration & dosage , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/mortality , Male , Middle Aged , Palliative Care , Prognosis , Retrospective Studies , Thioguanine/administration & dosage , Treatment Outcome
13.
Clinics ; 66(8): 1335-1340, 2011.
Article in English | LILACS | ID: lil-598372

ABSTRACT

OBJECTIVE: To evaluate the outcomes of acute myeloid leukemia patients who were older than 60 years of age at the time of diagnosis following the implementation of a treatment algorithm based on age, performance status, and cytogenetic results. METHODS: We retrospectively compared the results of 31 elderly acute myeloid leukemia patients (median age of 74 years) who were treated according to the new algorithm. RESULTS: Fifteen patients with a good performance status and no unfavorable karyotypes were treated with either intensive cytotoxic chemotherapy (<70 years, nine cases) or adapted etoposide, 6-thioguanine and idarubicine (>70 years, six cases); 16 cases with a poor performance status or unfavorable cytogenetics received supportive care only. Six patients achieved a complete remission and two achieved a partial remission after chemotherapy. There were three toxic deaths during induction, two in the adapted etoposide, 6-thioguanine and idarubicine group and one in the intensive cytotoxic chemotherapy group. The overall median survival time was 2.96 months, 1.3 months in the supportive care group, and 4.6 months in the treatment group. CONCLUSIONS: Our results illustrate the importance of treatment guidelines adapted to local resources in an attempt to improve the survival of elderly acute myeloid leukemia patients in developing countries.


Subject(s)
Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Leukemia, Myeloid, Acute/drug therapy , Algorithms , Brazil , Cytogenetic Analysis , Etoposide/administration & dosage , Hospitals, University , Idarubicin/administration & dosage , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/mortality , Palliative Care , Prognosis , Retrospective Studies , Treatment Outcome , Thioguanine/administration & dosage
14.
J Nat Prod ; 73(10): 1706-7, 2010 Oct 22.
Article in English | MEDLINE | ID: mdl-20886871

ABSTRACT

Research on antifungal compounds from the durable wood from French Guiana Amazonian forest trees highlights the correlation between the activity of their extracts against wood-rotting fungi and human pathogens. The fractionation of an ethyl acetate extract of Sextonia rubra wood led to the isolation of rubrenolide (1) and rubrynolide (2). The potential of compounds 1 and 2 is described through the evaluation of their activity against 16 pathogenic fungi and their cytotoxicity toward NIH-3T3 mammalian fibroblast cells.


Subject(s)
Acetals/isolation & purification , Acetals/pharmacology , Alkenes/isolation & purification , Alkenes/pharmacology , Alkynes/isolation & purification , Alkynes/pharmacology , Antifungal Agents/isolation & purification , Antifungal Agents/pharmacology , Basidiomycota/chemistry , Polyporaceae/chemistry , Trees/microbiology , Acetals/chemistry , Alkenes/chemistry , Alkynes/chemistry , Animals , Antifungal Agents/chemistry , French Guiana , Lauraceae/microbiology , Mice , Microbial Sensitivity Tests , Molecular Structure , NIH 3T3 Cells , Plant Stems/chemistry , Wood/microbiology
15.
Gene ; 466(1-2): 26-35, 2010 Oct 15.
Article in English | MEDLINE | ID: mdl-20621168

ABSTRACT

Over the last years an expanding family of small non-coding RNAs (sRNA) has been identified in eukaryotic genomes which behave as sequence-specific triggers for mRNA degradation, translation repression, heterochromatin formation and genome stability. To achieve their effectors functions, sRNAs associate with members of the Argonaute protein family. Argonaute proteins are segregated into three paralogous groups: the AGO-like subfamily, the PIWI-like subfamily, and the WAGO subfamily (for Worm specific AGO). Detailed phylogenetic analysis of the small RNA-related machinery components revealed that they can be traced back to the common ancestor of eukaryotes. However, this machinery seems to be lost or excessively simplified in some unicellular organisms such as Saccharomyces cerevisiae, Trypanosoma cruzi, Leishmania major and Plasmodium falciparum which are unable to utilize dsRNA to trigger degradation of target RNAs. We reported here a unique ORF encoding for an AGO/PIWI protein in T. cruzi which was expressed in all stages of its life cycle at the transcript as well as the protein level. Database search for remote homologues, revealed the presence of a divergent PAZ domain adjacent to the well supported PIWI domain. Our results strongly suggested that this unique AGO/PIWI protein from T. cruzi is a canonical Argonaute in terms of its domain architecture. We propose to reclassify all Argonaute members from trypanosomatids as a distinctive phylogenetic group representing a new subfamily of Argonaute proteins and propose the generic designation of AGO/PIWI-tryp to identify them. Inside the Trypanosomatid-specific node, AGO/PIWI-tryps were clearly segregated into two paralog groups designated as AGO-tryp and PIWI-tryp according to the presence or absence of a functional link with RNAi-related phenomena, respectively.


Subject(s)
Protozoan Proteins/analysis , Trypanosoma cruzi/classification , Trypanosoma cruzi/metabolism , Amino Acid Sequence , Animals , Cloning, Molecular , Evolution, Molecular , Models, Molecular , Molecular Sequence Data , Phylogeny , Protozoan Proteins/chemistry , RNA, Small Interfering , Sequence Homology, Nucleic Acid
16.
Anal Bioanal Chem ; 387(6): 2245-53, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17260139

ABSTRACT

The use of a copper solid amalgam electrode (CuSAE) for the analytical determination of triazine herbicides (atrazine and ametryne) instead of the conventional hanging mercury drop electrode (HMDE) is reported. The results obtained using electroanalytical methods utilizing each of these electrodes were also compared with those provided by the HPLC technique. The results indicated that the CuSAE electrode can be used to detect the herbicides studied, since the detection limits reached using the electrode (3.06 microg L-1 and 3.78 microg L-1 for atrazine and ametryne, respectively) are lower than the maximum values permitted by CONAMA (Brazilian National Council for the Environment) for wastewaters (50 microg L-1) and by the US EPA (Environmental Protection Agency of the United States) in natural water samples (10.00 microg L-1). An electroanalytical methodology employing CuSAE and square wave voltammetry (SWV) was successfully applied to the determination of atrazine and ametryne in natural water samples, yielding good recoveries (70.30%-79.40%). This indicates that the CuSAE provides a convenient substitute for the HMDE, particularly since the CuSAE minimizes the toxic waste residues produced by the use of mercury in HDME-based analyses.


Subject(s)
Alloys , Chromatography, High Pressure Liquid/methods , Herbicides/analysis , Refuse Disposal/methods , Triazines/analysis , Electrodes , Mercury
17.
Leuk Res ; 27(4): 363-6, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12531229

ABSTRACT

We present a case of acute myeloid leukemia with t(4;12). This translocation is rare and has been observed in acute leukemias with different but immature phenotypes. To the best of our knowledge, there are around 15 descriptions of t(4;12) in AML, and most interesting, presenting morphological aspects of a pseudo-lymphoid cell with dysplasia of other series.


Subject(s)
Chromosomes, Human, Pair 12 , Chromosomes, Human, Pair 4 , Leukemia, Myeloid/genetics , Translocation, Genetic , Acute Disease , Adult , Cytogenetic Analysis , Fatal Outcome , Humans , Immunophenotyping , Leukemia, Myeloid/pathology , Leukemia, Myeloid/therapy , Male
18.
Cell Transplant ; 11(6): 583-92, 2002.
Article in English | MEDLINE | ID: mdl-12428748

ABSTRACT

Vascular smooth muscle cells (VSMC) are ideal for systemic gene therapy because of their proximity to blood vessels and they have demonstrated long-term exogenous gene expression in vivo. However, the procedure generally followed to seed the transduced VSMC onto arteries denuded of endothelial cells usually induces stenosis and thrombosis, with a consequent high risk for use in humans. We demonstrate here that the vascular adventitia is a suitable place to introduce transduced VSMC and to secrete therapeutic proteins into the blood stream by a simple procedure, avoiding postoperative vascular complications. Transduced VSMC, with the retroviral vectors carrying the human growth hormone gene (hGH), were seeded into the adventitia of the rat abdominal aorta by single injection of a cell suspension. Based on the hGH and anti-hGH production in serum and on histological analysis of the removed aortas, we demonstrated hGH production over the 2-month experimental period. None of the animals used in the experiment showed stenosis, thrombosis, or other vascular or visible physiological abnormalities.


Subject(s)
Cell Transplantation/methods , Endothelium, Vascular/cytology , Gene Expression , Muscle, Smooth, Vascular/transplantation , 3T3 Cells , Animals , Aorta, Abdominal , Cells, Cultured , DNA, Complementary/genetics , Endothelium, Vascular/physiology , Genetic Therapy/methods , Genetic Vectors , Human Growth Hormone/blood , Human Growth Hormone/genetics , Humans , Kinetics , Mice , Muscle, Smooth, Vascular/cytology , Promoter Regions, Genetic , Rats , Rats, Wistar , Retroviridae , Terminal Repeat Sequences , Transfection/methods , Zinc/pharmacology
19.
Rev. bras. hematol. hemoter ; 23(2): 63-68, maio-ago. 2001. graf
Article in English | LILACS | ID: lil-338272

ABSTRACT

Bone marrow biopsy allows evaluation of cellularity, abnormal localization of immature precursors and fibrosis in myelodysplastic syndrome. It has been considered important to make diagnosis and prognosis of this disorder. The object of this study evaluated the influence of histopathological parameters, such as cellularity, erythroid/myeloid ratio, abnormal localization of immature precursors and marrow fibrosis, on survival of myelodysplastic syndrome patients. Forty-six patients, admitted from April 1985 to June 1998, and diagnosed as being myelodysplastic syndrome according to French-American-British criteria, were selected. There were 20 males and 26 females, with median age of 61 years. Forty-six bone marrow smears and 36 trephine biopsies were reviewed. Mean survival of hypocellular cases was 64.8 months and of hyper and normocellular cases was 31.8 months. Patients with predominance of erythroid hyperplasia had mean survival of 50.8 months, greater than those with predominance of myeloid hyperplasia (20.3 months). There was no statistical difference in survival of patients with or without abnormal localization of immature precursors and with or without marrow fibrosis. Bone marrow biopsy is a useful tool for the identification of parameters that influence prognosis in myelodysplastic syndrome. Hypocellularity and erythroid hyperplasia were correlated with longer survival while myeloid hyperplasia with poorer survival


A biópsia de medula óssea propicia a avaliação da celularidade global, dos precursores imaturos de localização anormal e de fibrose nas sídromes mielodisplásicas. O método tem sido considerado importante também para o diagnóstico e prognóstico da síndrome. O objetivo deste estudo foi o de o observar a influência de parâmetros histológicos como a celularidade, a relação eritróide mielóide, a presença de precursores imaturos de localização anormal e fibrose medular na sobrevida de pacients com a síndrome. De abril de 1985 a junho de 1998, 46 pacientes diagnosticados segundo os critérios do grupo Franco, Americano, Britânico foram estudados. A casuística era composta de 20 pacientes do sexo masculino e de 26 do sexo feminino com idade média de 61 anos. Foram revisados 46 esfregaços de aspirado de medula óssea e 36 cortes histológicos de bioópsia de medula óssea. A sobrevida média dos casos de hipocelularidade foi de 64,8 meses e dos casos que eram hiper ou normocelulares foi de 31,8 meses. Pacientes com a predominância de hiperplasia tiveram sobrevida média de 50,8 meses, que foi superior aos que apresentavam hiperplasia mielóide (20,3 meses). Não houve diferença estatística na sobrevida dos pacientes que apresentaram ou não fibrose medular. A biópsia de medula óssea deve ser considerada útil na identificação de prâmetros que influenciam no prognóstico da síndrome mielodisplásica. A hipocelularidade e a hiperplasia eritrocitária está realcionada com a sobrevida maior, enquanto a hiperplasia mielóide com a sobrevida mais curta.


Subject(s)
Humans , Male , Female , Middle Aged , Biopsy , Bone Marrow , Clinical Laboratory Techniques , Myelodysplastic Syndromes , Prognosis , Myelodysplastic Syndromes/pathology
20.
Medicina (Ribeiräo Preto) ; 33(3): 331-7, jul.-set. 2000. tab
Article in Portuguese | LILACS | ID: lil-283069

ABSTRACT

Modelo do estudo: observacional retrospectivo. Objetivo: conhecer a freqüência das alteraçöes oculopalpebrais em pacientes atendidos na Faculdade de Medicina de Botucatu, Säo Paulo. Método: o estudo foi realizado através da análise de fichas de atendimento no Serviço de Plástica Ocular da Faculdade de Medicina de Botucatu, durante o período de 12 anos, avaliando-se a idade, sexo, procedência e diagnóstico principal dos pacientes atendidos. Resultado: no período estudado foram avaliados 3323 pacientes, 58,3 por cento dos indivíduos eram procedentes da regiäo de Botucatu; a faixa etária superior a 60 anos (41,6 por cento) e o sexo feminino foram os prevalentes (55,7 por cento) e as patologias com alteraçäo da posiçäo palpebral foram as mais comuns. Comentários: as alteraçöes mais freqüêntes foram as relacionadas com a posiçäo das pálpebras e as lesöes benignas; o conhecimento da freqüência das alteraçöes oculopalpebrais é importante para a adoçäo de medidas preventivas e para planejar o treinamento de novos profissionais.


Subject(s)
Humans , Male , Female , Child , Adolescent , Adult , Middle Aged , Eye Injuries/epidemiology , Eyelid Diseases , Cilia , Schools, Medical , Eye Neoplasms
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