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Infection is one of the main causes of orthopedic implants failure, with antibiotic-resistant bacteria playing a crucial role in this outcome. In this work, antimicrobial nanogels were developed to be applied in situ as implant coating to prevent orthopedic-device-related infections. To that regard, a broad-spectrum antimicrobial peptide, Dhvar5, was grafted onto chitosan via thiol-norbornene "photoclick" chemistry. Dhvar5-chitosan nanogels (Dhvar5-NG) were then produced using a microfluidic system. Dhvar5-NG (1010 nanogels (NG)/mL) with a Dhvar5 concentration of 6 µg/mL reduced the burden of the most critical bacteria in orthopedic infections - methicillin-resistant Staphylococcus aureus (MRSA) - after 24 h in medium supplemented with human plasma proteins. Transmission electron microscopy showed that Dhvar5-NG killed bacteria by membrane disruption and cytoplasm release. No signs of cytotoxicity against a pre-osteoblast cell line were verified upon incubation with Dhvar5-NG. To further explore therapeutic alternatives, the potential synergistic effect of Dhvar5-NG with antibiotics was evaluated against MRSA. Dhvar5-NG at a sub-minimal inhibitory concentration (109 NG/mL) demonstrated synergistic effect with oxacillin (4-fold reduction: from 2 to 0.5 µg/mL) and piperacillin (2-fold reduction: from 2 to 1 µg/mL). This work supports the use of Dhvar5-NG as adjuvant of antibiotics to the prevention of orthopedic devices-related infections.
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INTRODUCTION: We have previously reported on neurogenic bladder dysfunction among Congenital Zika Vírus Syndrome (CZS) patients, but it is unknown how they will respond to treatment. OBJECTIVE: To assess whether children with neurological lower urinary tract dysfunction and CZS will respond to Standard therapies. METHODOLOGY: A prospective observational cohort study of children with CZS referred for urological assessment between 2016 and 2020 to our quaternary center in Brazil. Urological protocol included clinical history, urinalysis and culture, renal and bladder ultrasonography and urodynamic study. Patients were treated based on findings from the first evaluation, with oxybutynin chloride for overactive bladder and low bladder compliance, clean intermittent catheterization for ineffective bladder emptying, or dual therapy when both were observed. Urological outcomes were evaluated between the first and second visits considering patient's adherence. Outcomes measured included clinical, imaging, and urodynamic variables. Data was analyzed using the IBM SPSS 22 software. RESULTS: From the cohort of 90 patients, 56 completed the second urodynamic assessment and were included. One presented underactive bladder and 55 overactive bladder. Among these 55, 39 were adherent and 16 non-adherents to the prescribed treatment. Among the 39 adherents, 8 adhered regularly to oxybutynin and clean intermittent catheterization (CIC), 29 to oxybutynin alone, and two to catheterization alone. During follow-up, the number of patients with urinary tract infection and postvoid residual increased, but all other parameters had improved. Renal and bladder ultrasonography improved in 10, maximum bladder pressure decreased in 22 and maximum cystometric capacity and compliance increased in 14 patients. Sixteen patients did not adhere regularly to the prescribed treatment and although the number of patients with urinary tract infection reduced with antibiotic therapy, their bladder capacity and compliance did not improve during follow-up. DISCUSSION: Ultrasonographic and urodynamic improvements were observed after 10.8 ± 7.5 months of treatment, including one patient with ureterohydronephrosis that resolved. Adherence to CIC remains a challenge and reflected in the number of patients presenting urinary tract infection and postvoid residual. The immediate clinical relevance is the major study strength, given the previously uncharacterized therapy options for this patient population. The number of patients remains one of the study limitations, reducing our ability to perform more advanced statistical analyses. CONCLUSION: Patients with Zika-related neurological lower urinary tract dysfunction may benefit from conventional therapies. Results confirmed ultrasonographic and urodynamic improvements after treatment, although not statically significant. Adherence to treatment, specifically to CIC, remains a challenge.
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Bexiga Urinaria Neurogênica , Infecção por Zika virus , Zika virus , Criança , Seguimentos , Humanos , Estudos Prospectivos , Bexiga Urinaria Neurogênica/etiologia , Bexiga Urinaria Neurogênica/terapia , Urodinâmica , Infecção por Zika virus/complicações , Infecção por Zika virus/terapiaRESUMO
In osteoarthritis (OA), pain is the dominant clinical symptom, yet the therapeutic approaches remain inadequate. The knowledge of the nociceptive mechanisms in OA, which will allow to develop effective therapies for OA pain, is of utmost need. In this study, we investigated the nociceptive mechanisms involved in post-traumatic OA pain, using the destabilization of the medial meniscus (DMM) mouse model. Our results revealed the development of peripheral pain sensitization, reflected by augmented mechanical allodynia. Along with the development of pain behaviour, we observed an increase in the expression of calcitonin gene-related peptide (CGRP) in both the sensory nerve fibers of the periosteum and the dorsal root ganglia. Interestingly, we also observed that other nociceptive mechanisms commonly described in non-traumatic OA phenotypes, such as infiltration of the synovium by immune cells, neuropathic mechanisms and also central sensitization were not present. Overall, our results suggest that CGRP in the sensory nervous system is underlying the peripheral sensitization observed after traumatic knee injury in the DMM model, highlighting the CGRP as a putative therapeutic target to treat pain in post-traumatic OA. Moreover, our findings suggest that the nociceptive mechanisms involved in driving pain in post-traumatic OA are considerably different from those in non-traumatic OA.
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Nociceptores/fisiologia , Osteoartrite/fisiopatologia , Dor/fisiopatologia , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Sensibilização do Sistema Nervoso Central/fisiologia , Modelos Animais de Doenças , Gânglios Espinais/metabolismo , Gânglios Espinais/fisiopatologia , Articulação do Joelho/metabolismo , Articulação do Joelho/fisiopatologia , Meniscos Tibiais , Camundongos , Nociceptores/metabolismo , Osteoartrite/metabolismo , Dor/metabolismo , Doenças do Sistema Nervoso Periférico/metabolismo , Doenças do Sistema Nervoso Periférico/fisiopatologiaRESUMO
INTRODUCTION: Congenital Zika syndrome (CZS) is a recently discovered condition that affects central nervous system structures that control the lower urinary tract. The first cases of neurogenic bladder (NB) were recently reported as a sequalae of CZS in neurologically impaired children. OBJECTIVE: Our goal is to further evaluate NB in the setting of CZS, identifying urological risk indicators in hopes that early diagnosis will mitigate the impact of the disease. STUDY DESIGN: Urological assessment was performed in all patients with CZS and neurological impairment who were referred to our urodynamic clinic between June 2016 and May 2018. Neurogenic bladder was confirmed by urodynamic evaluation, and urological risk was based on urodynamic results. RESULTS: Sixty-nine patients with CZS were tested. The majority (63 patients, 91.3%) presented with overactive bladder with increased pressures and reduced capacity for age (table 1). Different urodynamic patterns were observed, and the association of reduced bladder capacity for age, high bladder-filling pressure, and increased postvoid residual were frequently observed. DISCUSSION: NB continues to be consistently diagnosed in our cohort of CZS, mostly with high-risk indicators for renal impairment. When not intervened upon in a timely manner, NB can cause progressive damage to the urinary tract, but the lack of knowledge that CZS causes NB delays investigation and treatment. Parents and health professionals will need to be sensitized to the risks that ZIKV can pose to the urinary tract so that appropriate therapies are initiated to prevent irreversible renal damage. CONCLUSION: NB is a common condition among our patients with CZS and microcephaly. This is a new cause of NB, unknown to urologists. While further investigation is necessary to understand long-term disease behavior and therapeutic response, increased knowledge among urologists may help to reduce morbidity related to untreated NB and to mitigate the disease burden for patients and families.
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Bexiga Urinaria Neurogênica/etiologia , Bexiga Urinária/fisiopatologia , Urodinâmica/fisiologia , Urologistas , Infecção por Zika virus/complicações , Zika virus , Pré-Escolar , Diagnóstico Precoce , Feminino , Humanos , Lactente , Masculino , Síndrome , Bexiga Urinaria Neurogênica/diagnóstico , Bexiga Urinaria Neurogênica/fisiopatologia , Infecção por Zika virus/congênito , Infecção por Zika virus/virologiaRESUMO
Physicochemical characteristics were determined in the longissimus lumborum muscle, after 8 days of ageing of steers (n=12) and bulls (n=12) from Mertolenga breed slaughtered directly from pasture (day 0) or after a finishing period of 50, 100 and 150 days in a feed-lot facility. Bulls and steers presented similar live weight (averaging 388 kg), carcass weight (CW; averaging 213 kg), dressing percentage (averaging 60%), carcass fatness (11.9% CW) and carcass fat thickness (averaging 3.03 mm). Live weight, CW, carcass fatness and fat thickness increased along time-on-feed. Gender only had a negligible effect on meat characteristics, with b and h being the only parameters of colour affected by gender, also presenting a significant interaction gender × time-on-feed. Nevertheless, both the genders presented a high-quality grade concerning tenderness (Warner-Bratzler shear force (WBSF)). L increased until 50 days on feed and decreased afterwards, whereas a and C values increased along time-on-feed. Pigment content was also affected by time-on-feed and showed a gender × time-on-feed interaction. Beef colour became darker and redder along time-on-feed, but still in a colour range highly acceptable by Portuguese consumers. Despite the increase in intramuscular fat and myofibrillar fragmentation index, as well as the decrease in collagen content of steers and bulls along time-on-feed, it did not affect the tenderness/hardness, indicating a small effect of time-on-feed in meat characteristics. Despite only small differences in carcass characteristics and meat-quality parameters that have been noticed along time-on-feed, those differences were only significant after 100 days on feed. Principal component analysis (PCA) was performed. The first PC axis (39.6% of the total variance) included colour variables a, b and C, and carcass fatness, fat thickness, CW and live weight, whereas the second one (12.7% of the total variance) included h, cooking losses and dressing-out. The principal component (PC) analysis confirmed the lack of differences between bulls and steers and indicates a differentiation of the first two periods of feeding (0 and 50 days on feed) from the two latter (100 and 150 days on feed) periods of feeding.
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Ração Animal , Criação de Animais Domésticos/métodos , Bovinos/fisiologia , Carne/normas , Fenômenos Fisiológicos da Nutrição Animal , Animais , Peso Corporal , Cruzamento , Masculino , Músculo Esquelético/química , Músculo Esquelético/metabolismo , Orquiectomia/veterináriaRESUMO
Three quality branded meats (n=68), "Vitela Tradicional do Montado"-PGI veal, Mertolenga-PDO veal and Mertolenga-PDO beef were analysed for cholesterol (HPLC-UV), α-tocopherol (HPLC-FD), fatty acid composition (GC-FID), including conjugated linoleic acid (CLA) isomeric profile (Ag+-HPLC), and nutritional value of lipids. All the meats analysed had similar contents (P>0.05) of cholesterol, α-tocopherol and intramuscular fat. In contrast, the percentage of 18:0 was lower for PGI veal, and that of 18:1 c9 was higher in PDO veal, whilst the percentage of 18:2 n-6 was higher in PDO beef, relative to other two meats. The content of total CLA and the percentage of its t11,c13 isomer were higher, and the n-6/n-3 ratio was lower, in PDO veal, relative to the other two meats. The data suggested that PGI veal has higher variability for most fatty acids than the other two types of meat. Finally, a discriminant analysis was conducted and the three meat types were well discriminated using the meat fatty acid profile as variables.
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Examinaram-se a adesão, a germinação, a penetração e a colonização de larvas e ninfas de Rhipicephalus sanguineus por Metarhizium anisopliae, assim como as lesões infringidas pelo fungo nas respectivas fases do ciclo de vida do ácaro. Realizaram-se infecções experimentais em 11 grupos contendo 250 larvas e 11 grupos contendo 75 ninfas de R. sanguineus, por meio de banho, durante três minutos sob agitação manual, em suspensão contendo 10(8) conídios/ml do fungo. Nos grupos-controles, o banho foi realizado usando o veículo da suspensão. Larvas e ninfas foram processadas para um estudo histopatológico e de microscopia eletrônica de varredura nos seguintes tempos após a infecção: uma e 18 horas, e um, dois, três, quatro, cinco, seis, sete, nove e 11 dias. A germinação dos conídios ocorreu em até 18 horas pós-inoculação, e o fungo penetrou nas larvas e ninfas através do tegumento, dois e três dias após a infecção, respectivamente. Após penetração, o fungo invadiu o corpo das larvas e ninfas, promovendo uma colonização difusa, sem preferência aparente por tecidos específicos. Lesões significativas não foram observadas. A morte das larvas e ninfas ocorreu no terceiro e quarto dias pós-infecção, e a esporulação do patógeno sobre o cadáver foi iniciada no sexto dia pós-infecção.
The adhesion, germination and colonization of Rhipicephalus sanguineus larvae and nymphs by Metarhizium anisopliae as well as the lesions caused by the fungus were studied. For this purpose, 11 groups of 250 larvae each and 11 groups of 75 nymphs each were bathed during 3 minutes under manual shaking in a 10(8) conidia/ml suspension. Corresponding control groups were bathed only in the suspension vehicle. Ticks were also submitted to both conventional microscopy and scanning eletronmicrocopy analyses at several post-infection periods (1 and 18 hours and 1, 2, 3, 4, 5, 6, 7, 9, and 11 days). Conidial germination occurred in less than 18 hours post-inoculation and the fungus penetration through the tegument into the larvae and nymphs in, respectively, two and three days post-infection. Following penetration, the fungus invaded the body of the ticks and colonized it diffusely without a noticeable predilection for tissue, but no apparent lesions were observed. Death of larvae and nymphs occurred on the 3rd and 4th post-infection days and pathogen sporulation over the dead tick began on the 6th post-infection day.
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Animais , Cães , Fungos , Infecções , Metarhizium , Microbiologia , Ácaros , Controle Biológico de Vetores , Rhipicephalus sanguineusRESUMO
Strategically positioned in peripheral tissues, immune sentinel cells sense microbes and/or their shed products through different types of pattern-recognition receptors. Upon secretion, pre-formed pro-inflammatory mediators activate the microvasculature, inducing endothelium/neutrophil adherence and impairing endothelium barrier function. As plasma proteins enter into peripheral tissues, short-lived proinflammatory peptides are rapidly generated by limited proteolysis of complement components and the kininogens (i.e. kinin-precursor proteins). While much emphasis has been placed on the studies of the vascular functions of kinins, their innate effector roles remain virtually unknown. A few years ago, we reported that exogenous bradykinin (BK) potently induces dendritic cell (DC) maturation, driving IL-12-dependent Th1 responses through the activation of G-protein-coupled BK B(2) receptors (B(2)R). The premise that immature DC might sense kinin-releasing pathogens through B(2)R was demonstrated in the subcutaneous mouse model of Trypanosoma cruzi infection. Analysis of the dynamics of parasite-evoked inflammation revealed that activation of TLR2/neutrophils drives the influx of plasma proteins, including kininogens, into peripheral tissues. Once associated to cell surfaces and/or extracellular matrices, the surface-bound kininogens are cleaved by T. cruzi cysteine proteases. Acting as short-lived 'danger' signals, kinins activate DC via B(2)R, converting them into Th1 inducers. Fine tuned control of the extravascular levels of these natural peptide adjuvants is exerted by kinin-degrading metallopeptidases, e.g. Angiotensin converting enzyme (ACE/CD143). In summary, the studies in the subcutaneous model of T. cruzi infection revealed that the peripheral levels of BK, a DC maturation signal, are controlled by TLR2/neutrophils and ACE, respectively characterized as positive and negative modulators of innate/adaptive immunity.
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Bradicinina/metabolismo , Diferenciação Celular/imunologia , Células Dendríticas/metabolismo , Imunidade Ativa , Mediadores da Inflamação/fisiologia , Cininogênios/fisiologia , Peptídeo Hidrolases/metabolismo , Animais , Células Dendríticas/enzimologia , Células Dendríticas/patologia , Humanos , Mediadores da Inflamação/metabolismo , Cininogênios/metabolismo , Transdução de Sinais/imunologiaRESUMO
Acanthoscelides obtectus is a devastating storage insect pest capable of causing severe bean crop losses. In order to maintain their own development, insect pest larvae feed continuously, synthesizing efficient digestive enzymes. Among them, cysteine proteinases (CPs) are commonly produced as inactive precursors (procysteines), requiring a cleavage of the peptide proregion to become active. The proregion fits tightly into the active site of procysteines, efficiently preventing their activity. In this report, a CP cDNA (cpao) was isolated from A. obtectus midgut larvae. In silico studies indicated that the complete CP sequence contains a hydrophobic signal peptide, a prodomain and a conserved catalytic region. Moreover, the encoding cDNA contains 963bp translating into a 321 residue protein, CPAo, which was expressed in E. coli, fused with thioredoxin. Enzymatic assays using the recombinant protein revealed that the enzyme was catalytically active, being able to cleave the synthetic substrate Z-Phe-Arg-7-AMC. Additionally, this report also focuses the cpao propeptide (PCPAo) subcloning and expression. The expressed propeptide efficiently inhibited CPAo, as well as digestive CP of other bean bruchids. Little or no activity was found against proteolytic enzymes of two other coleopterans: Rhyzopertha dominica and Anthonomus grandis. The data reported here indicate the possibility of endogenous propeptides as a novel strategy on bruchids control, which could be applicable to bean improvement programs.
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Besouros/enzimologia , Cisteína Endopeptidases/metabolismo , Inibidores de Cisteína Proteinase/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação , Clonagem Molecular , Sequência Conservada , Cisteína Endopeptidases/química , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/isolamento & purificação , Inibidores de Cisteína Proteinase/química , Inibidores de Cisteína Proteinase/genética , DNA Complementar/genética , Escherichia coli/genética , Dados de Sequência Molecular , Ligação Proteica , Sinais Direcionadores de Proteínas , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Tiorredoxinas/metabolismoRESUMO
Cysteine proteinases (CPs) are synthesized as zymogens and converted to mature proteinase forms by proteolytic cleavage and release of their pro domain peptides. A cDNA encoding a papain-like CP, called hgcp-Iv, was isolated from a Heterodera glycines J2 cDNA library, expressed and utilized to assess the ability of its propeptide to inhibit proteinase in its active form. The hgcp-Iv cDNA sequence encodes a polypeptide of 374 amino acids with the same domain organization as other cathepsin L-like CPs, including a hydrophobic signal sequence and a pro domain region. HGCP-Iv, produced in Escherichia coli as a fusion protein with thioredoxin, degrades the synthetic peptide benzyloxycarbonyl-Phe-Arg-7-amido-4-methylcoumarin and is inhibited by E-64, a substrate and inhibitor commonly used for functional characterization of CPs. Recombinant propeptides of HGCP-Iv, expressed in E. coli, presented high inhibitory activity in vitro towards its cognate enzyme and proteinase activity of Meloidogyne incognita females, suggesting its usefulness in inhibiting nematode CPs in biological systems. Cysteine proteinases from other species produced no noticeable activity.
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Feminino , Animais , Cisteína Endopeptidases/genética , Doenças das Plantas/parasitologia , Inibidores de Cisteína Proteinase/genética , Peptídeos/genética , Tylenchoidea/enzimologia , Sequência de Aminoácidos , Sequência de Bases , Cisteína Endopeptidases/metabolismo , DNA Complementar/genética , DNA de Helmintos/genética , Inibidores de Cisteína Proteinase/metabolismo , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Peptídeos/metabolismo , Tylenchoidea/genéticaRESUMO
In spite of the fact that most of the members of Palmaceae contain high concentrations of oil, its potential as a source of oil and protein for human consumption has not been exploited. The pulp and kernels of the Eliaes guineensis palm fruits grown in the Northeast region of Brazil were analyzed only for their proximate composition. The lipid content of the dried pulp and kernels was 73.2% and 32.6%, respectively. Hexane extracted oils from the pulp and kernels yielded similar refractive indices, specific gravity but different peroxide, acid, iodine and saponification values. Gas chromatographic analysis revealed the presence of 24 and 18 fatty acids in pulp and kernel oils, respectively. The principal saturated acid of the pulp oil was palmitic acid (36.9% of the total), and lauric acid (53.3%) for kernel oil. Oleic acid was the predominant monounsaturated fatty acid in both the oils though its concentration in the pulp and kernel oils was 45.29% and 5.5%, respectively. In relation to the essential amino acids, pulp proteins presented a better profile than the kernel proteins. In comparison to the FAO reference protein, the pulp proteins were deficient in methionine, lysine and threonine (16.8%, 51.6% and 93.5% of FAO reference protein) but contained leucine, valine, isoleucine and phenylalanine in optimal concentrations. With exception to phenylalanine and valine (102.2% and 111.4% of reference protein, respectively), the kernel proteins were deficient in all other essential amino acids. The oils from this palm can be used as culinary oil and in margarine manufacture, while pulp could be a supplement for essential amino acids leucine, isoleucine, phenylalanine and valine with other protein sources that are deficient in these amino acids.
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Ácidos Graxos/análise , Óleos de Plantas/química , Brasil , Plantas Comestíveis , Proteínas/análiseRESUMO
Environmental and genetic factors affecting the in vitro spontaneous mutation frequencies to aminoglycoside resistance in Escherichia coli K12 were investigated. Spontaneous mutation frequencies to kanamycin resistance were at least 100 fold higher on modified Luria agar (L2) plates, when compared to results obtained in experiments carried out with Nutrient agar (NA) plates. In contrast to rifampincin, the increased mutability to kanamycin resistance could not be attributed to a mutator phenotype expressed by DNA repair defective strains. Kanamycin mutant selection windows and mutant preventive concentrations on L2 plates were at least fourfold higher than on NA plates, further demonstrating the role of growth medium composition on the mutability to aminoglycosides. Mutability to kanamycin resistance was increased following addition of sorbitol, suggesting that osmolarity is involved on the spontaneous mutability of E. coli K12 strains to aminoglycosides. The spontaneous mutation rates to kanamycin resistance on both L2 and NA plates were strictly associated with the selective antibiotic concentrations. Moreover, mutants selected at different antibiotic concentrations expressed heterogeneous resistance levels to kanamycin and most of them expressing multiple resistance to all tested aminoglycoside antibiotics (gentamicin, neomycin, amykacin and tobramycin). These results will contribute to a better understanding of the complex nature of aminoglycoside resistance and the emergence of spontaneous resistant mutants among E. coli K12 strains
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Aminoglicosídeos , Escherichia coli , Mutação/genética , Resistência Microbiana a Medicamentos , Meio AmbienteRESUMO
Lysosomal cysteine proteases from mammalian cells and plants are regulated by endogenous tight-binding inhibitors from the cystatin superfamily. The presence of cystatin-like inhibitors in lower eukaryotes such as protozoan parasites has not yet been demonstrated, although these cells express large quantities of cysteine proteases and may also count on endogenous inhibitors to regulate cellular proteolysis. Trypanosoma cruzi, the causative agent of Chagas' heart disease, is a relevant model to explore this possibility because these intracellular parasites rely on their major lysosomal cysteine protease (cruzipain) to invade and multiply in mammalian host cells. Here we report the isolation, biochemical characterization, developmental stage distribution and subcellular localization of chagasin, an endogenous cysteine protease inhibitor in T. cruzi. We used high temperature induced denaturation to isolate a heat-stable cruzipain-binding protein (apparent molecular mass, 12 kDa) from epimastigote lysates. This protein was subsequently characterized as a tight-binding and reversible inhibitor of papain-like cysteine proteases. Immunoblotting indicated that the expression of chagasin is developmentally regulated and inversely correlated with that of cruzipain. Gold-labeled antibodies localized chagasin to the flagellar pocket and cytoplasmic vesicles of trypomastigotes and to the cell surface of amastigotes. Binding assays performed by probing living parasites with fluorescein (FITC)-cruzipain or FITC-chagasin revealed the presence of both inhibitor and protease at the cell surface of amastigotes. The intersection of chagasin and cruzipain trafficking pathways may represent a checkpoint for downstream regulation of proteolysis in trypanosomatid protozoa.
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Cistatinas/metabolismo , Cisteína Endopeptidases/metabolismo , Inibidores de Cisteína Proteinase/metabolismo , Proteínas de Protozoários/metabolismo , Trypanosoma cruzi/metabolismo , Animais , Sítios de Ligação , Membrana Celular/metabolismo , Doença de Chagas/metabolismo , Cistatinas/biossíntese , Cistatinas/genética , Inibidores de Cisteína Proteinase/biossíntese , Inibidores de Cisteína Proteinase/genética , Humanos , Cinética , Papaína/antagonistas & inibidores , Proteínas de Protozoários/biossíntese , Proteínas de Protozoários/genética , Coelhos , Frações Subcelulares , Trypanosoma cruzi/crescimento & desenvolvimentoRESUMO
The pre-concentration of mercury(II) and methylmercury by adsorption of their dithiophosphoric acid diacyl ester (DDTP) chelates on a C18 column, then detection with cold-vapor atomic-absorption spectrometry was investigated. Conditions such as sample pH, reductant and chelating agent flow and concentration, and eluent and carrier gas flow were optimized. Optimization was performed by use of evolutionary operation with a proper factorial design. At a sample flow of 5.3 mL min(-1) and a loading time of 4.5 min, column adsorption efficiency ranged from 88 to 93% for both species. Detection limits down to 10 ng L(-1) were obtained at a sample throughput of 12 h(-1). There was good agreement between found and certified values in the analysis of certified reference materials after their microwave-assisted mineralization with HNO3 and H2O2.
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Quelantes/química , Mercúrio/análise , Compostos de Metilmercúrio/análise , Fosfatos/química , Ésteres/química , Análise de Injeção de Fluxo , Padrões de Referência , Espectrofotometria Atômica/métodosRESUMO
Chagasin, a protein from Trypanosoma cruzi, is the first member of a new family of tight binding cysteine protease inhibitors [Monteiro, A.C.S., Abrahamson, M., Lima, A.P.C., Vannier-Santos, M.A. and Scharfstein, J. (2001) J. Cell Sci., in press] [corrected]. Despite its lack of significant sequence identity with known proteins, convincing structural models, using variable light chain templates, could be constructed on the basis of threading results. Experimental support for the final structure came from inhibition data for overlapping oligopeptides spanning the chagasin sequence. Chagasin therefore exemplifies a new protease inhibitor structural class and a new natural use for an immunoglobulin-like domain. Limited sequence resemblance suggests that chagasin may represent the result of a rare horizontal gene transfer from host to parasite.
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Inibidores de Cisteína Proteinase/química , Transferência Genética Horizontal , Imunoglobulinas/química , Dobramento de Proteína , Proteínas de Protozoários/química , Trypanosoma cruzi/química , Sequência de Aminoácidos , Animais , Inibidores de Cisteína Proteinase/genética , Modelos Moleculares , Dados de Sequência Molecular , Proteínas de Protozoários/genética , Homologia de Sequência de AminoácidosRESUMO
Fungal infection of the thyroid is rare. Most reported cases have involved Aspergillus, Coccidioides, and Candida species in the setting of disseminated disease. Infection of the thyroid with Histoplasma capsulatum is rarely reported as part of disseminated disease, even in geographic areas where histoplasmosis is endemic. We report a 52-year-old woman with a previous Hashimoto's disease and non-Hodgkin's lymphoma in which a diffuse enlarged thyroid gland with a large nodule was the only apparent locus of histoplasmosis. Fine-needle aspiration of the thyroid was an important diagnostic tool in establishing the diagnosis of histoplasmosis of the thyroid. The patient was initially treated with itraconazole (400 mg/day) for the fungal infection and six cycles of chemotherapy for the lymphoma. At a 6-month follow-up examination, the patient was doing well on suppressive therapy of itraconazole (200 mg/day), with no symptoms and with regression of the thyroid nodule and cervical adenopathy.
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Histoplasmose/patologia , Doenças da Glândula Tireoide/patologia , Glândula Tireoide/microbiologia , Antifúngicos/uso terapêutico , Feminino , Histoplasmose/complicações , Histoplasmose/tratamento farmacológico , Humanos , Itraconazol/uso terapêutico , Linfoma não Hodgkin/complicações , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/patologia , Macrófagos/microbiologia , Macrófagos/patologia , Pessoa de Meia-Idade , Doenças da Glândula Tireoide/complicações , Doenças da Glândula Tireoide/microbiologia , Glândula Tireoide/patologia , Tireoidite Autoimune/complicações , Resultado do TratamentoRESUMO
CONTEXT: The subjectivity of pain causes enormous difficulties in evaluating neonatal pain with a single, practical and easy-to-apply tool. Pain evaluation in the neonatal period should be performed by valid, safe, useful and feasible methods. OBJECTIVE: To evaluate the validity of the Neonatal Facial Coding System (NFCS), Neonatal Infant Pain Scale (NIPS), heart rate (HR) and O2 saturation (O2 sat) for neonatal pain assessment. DESIGN: Prospective, double-blind randomized trial. SETTING: A secondary level maternity hospital. PARTICIPANTS: 70 healthy neonates requiring bilirubin dosage were randomly assigned to receive a venous puncture (P: n = 33, BW 3.2 kg, SD 0.6; GA 39 wk, SD 1; 59 h of life, SD 25) or an alcohol swab friction (F: n = 37; BW 3.1 kg, SD 0.5; GA 39 wk, SD 1; 52 h of life, SD 17). INTERVENTION: All measurements were taken prior to (PRE), during (TO), and 1 (T1), 3(T3), 5(T5) and 10(T10) minutes after the procedure. MEASUREMENTS: A neonatologist evaluated NFCS, NIPS, HR and O2 sat by pulse oxymetry. RESULTS: Median NFCS and NIPS results at T0, T1 and T3 were higher in P group, compared to F. More P neonates presented NFCS > 2 and/or NIPS > 3 at T0, T1 and T3. HR was lower in P group at T1. Average O2 sat was above 90% during the whole study period in both groups. CONCLUSION: NFCS and NIPS are suitable instruments for neonatal pain evaluation. Heart rate and O2 saturation can be used only as auxiliary methods.
Assuntos
Medição da Dor/métodos , Dor/diagnóstico , Doença Aguda , Método Duplo-Cego , Expressão Facial , Frequência Cardíaca , Humanos , Recém-Nascido , Estudos Prospectivos , Reprodutibilidade dos TestesRESUMO
Myiasis is a parasitic infestation caused by larvae of several fly species. Diagnosis and treatment are simple. This infestation is, however, rarely seen in the vulvar area. We present a short review of the disease and the case of a 19-year-old pregnant girl with vulvar myiasis and concomitant syphilis, vaginal trichomoniasis and genital candidiasis. The patient was also positive for human immunodeficiency virus.
Assuntos
Miíase/etiologia , Doenças da Vulva/etiologia , Adulto , Feminino , Humanos , GravidezRESUMO
A lectin was isolated from the saline extract of Artocarpus incisa seed by affinity chromatography on cross-linked Adenanthera pavonina galactomannan in 0.15 M NaCl. The lectin was also retained in a D-gal-agarose resin and had no requirements for divalent metal cations (Ca2+ and Mn2+) for activity. The lectin contains 2.1% of carbohydrate and is characterized by high contents of acidic and hydroxylated amino acids. The lectin presented two protein bands in SDS-PAGE, with M(r) 15.5 and 12 kDa, respectively, and contains no alpha-helix, 64% antiparallel beta-sheet and 21% parallel beta-sheet/beta-turn. When submitted to gel filtration in Superose 12 R (FPLC) and Superdex 75 HR 5/5 (HPLC) columns, the lectin showed an M(r) of 48-49 kDa, suggesting a tetrameric structure.