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1.
Tuberculosis (Edinb) ; 125: 101995, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32979676

RESUMO

The Mycobacterium tuberculosis complex (MTC) has affected South American populations since ca. 200 years BCE. In Argentina, possible cases date from ca. 1000-1400 Common Era (CE). This paper describes the oldest (905-1030 CE) confirmed case of tuberculosis (TB) in a young adult male from Lomitas de Saujil (Tinogasta, Catamarca, Argentina). Osteolytic lesions on the bodies of the lower spine were macroscopically and radiographically identified. Bilateral new bone formation was seen on the visceral vertebral third of several ribs and in long bones, compatible with hypertrophic osteoarthropathy. Representative rib and hand bones gave profiles for MTC-specific C27-C32 mycocerosic acid lipid biomarkers; these were strongest in one heavily-lesioned lower rib, which also had MTC-diagnostic C76-C89 mycolic acids and positive amplification of MTC-typical IS6110 aDNA fragments. During the first millennium CE, the intense social interaction, the spatial circumscription of villages among the pre-Hispanic societies in the mesothermal valleys of Catamarca and the fluid contacts with the Eastern lowlands, valleys and puna, were factors likely to favor disease transmission. It is proposed that TB arrived from northern Chile and dispersed towards the northeast into the Yocavil valley, where several cases of TB infection were macroscopically identified for a later chronology.


Assuntos
Osso e Ossos/diagnóstico por imagem , DNA Bacteriano/história , Mycobacterium tuberculosis/genética , Paleopatologia/métodos , Tuberculose Osteoarticular/história , Adulto , Argentina/epidemiologia , Osso e Ossos/microbiologia , DNA Bacteriano/análise , História do Século XV , História do Século XVI , História Antiga , História Medieval , Humanos , Incidência , Masculino , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Osteoarticular/diagnóstico , Tuberculose Osteoarticular/epidemiologia
2.
Bioresour Technol ; 221: 607-615, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27693726

RESUMO

The effect of specific narrow light-emitting diode (LED) wavelengths (red, green, blue) and a combination of LED wavelengths (red, green and blue - RGB) on biomass composition produced by Porphyridium purpureum is studied. Phycobiliprotein, fatty acids, exopolysaccharides, pigment content, and the main macromolecules composition were analysed to determine the effect of wavelength on multiple compounds of commercial interest. The results demonstrate that green light plays a significant role in the growth of rhodophyta, due to phycobiliproteins being able to harvest green wavelengths where chlorophyll pigments absorb poorly. However, under multi-chromatic LED wavelengths, P. purpureum biomass accumulated the highest yield of valuable products such as eicosapentaenoic acid (∼2.9% DW), zeaxanthin (∼586µgg-1DW), ß-carotene (397µgg-1DW), exopolysaccharides (2.05g/L-1), and phycobiliproteins (∼4.8% DW). This increased accumulation is likely to be the combination of both photo-adaption and photo-protection, under the combined specific wavelengths employed.


Assuntos
Biotecnologia/instrumentação , Biotecnologia/métodos , Porphyridium/metabolismo , Biomassa , Clorofila/metabolismo , Ácidos Graxos/metabolismo , Luz , Ficobiliproteínas/metabolismo , Polissacarídeos/metabolismo , Porphyridium/crescimento & desenvolvimento , beta Caroteno/metabolismo
3.
PLoS One ; 10(5): e0124282, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25970602

RESUMO

We have examined a 5th to 6th century inhumation from Great Chesterford, Essex, UK. The incomplete remains are those of a young male, aged around 21-35 years at death. The remains show osteological evidence of lepromatous leprosy (LL) and this was confirmed by lipid biomarker analysis and ancient DNA (aDNA) analysis, which provided evidence for both multi-copy and single copy loci from the Mycobacterium leprae genome. Genotyping showed the strain belonged to the 3I lineage, but the Great Chesterford isolate appeared to be ancestral to 3I strains found in later medieval cases in southern Britain and also continental Europe. While a number of contemporaneous cases exist, at present, this case of leprosy is the earliest radiocarbon dated case in Britain confirmed by both aDNA and lipid biomarkers. Importantly, Strontium and Oxygen isotope analysis suggest that the individual is likely to have originated from outside Britain. This potentially sheds light on the origins of the strain in Britain and its subsequent spread to other parts of the world, including the Americas where the 3I lineage of M. leprae is still found in some southern states of America.


Assuntos
Genes Bacterianos , Genoma Bacteriano , Hanseníase Virchowiana/história , Mycobacterium leprae/genética , Adulto , Radioisótopos de Carbono , Fíbula/microbiologia , Fíbula/patologia , Genótipo , História Medieval , Humanos , Hanseníase Virchowiana/microbiologia , Hanseníase Virchowiana/patologia , Lipídeos/isolamento & purificação , Masculino , Ossos do Metatarso/microbiologia , Ossos do Metatarso/patologia , Mycobacterium leprae/classificação , Mycobacterium leprae/isolamento & purificação , Mycobacterium leprae/metabolismo , Osteologia , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Tálus/microbiologia , Tálus/patologia , Reino Unido
4.
Tuberculosis (Edinb) ; 95 Suppl 1: S4-S12, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25819157

RESUMO

The question of pre-neolithic tuberculosis is still open in paleopathological perspective. One of the major interests is to explore what type of infection could have existed around the early stage of animal domestication. Paleopathological lesions evoking skeletal TB were observed on five human skeletons coming from two PPNB sites in Syria, which belongs to the geographical cradle of agriculture. These sites represent respectively pre-domestication phase (Dja'de el Mughara, Northern Syria, 8800-8300 BCE cal.) and early domestication phase (Tell Aswad, Southern Syria, 8200-7600 BCE cal.). MicroCT scan analyses were performed on two specimens (one per site) and revealed microscopic changes in favor of TB infection. Detection of lipid biomarkers is positive for two specimens (one per site). Initial molecular analysis further indicates the presence of TB in one individual from Dja'de. Interestingly, no morphological evidence of TB was observed on animal remains of wild and newly domesticated species, discovered in these sites. These observations strongly suggest the presence of human tuberculosis before domestication and at its early stages.


Assuntos
Tuberculose Osteoarticular/história , Adulto , Agricultura/história , Animais , Animais Domésticos , Antropologia Médica , Biomarcadores/análise , Criança , Pré-Escolar , DNA Bacteriano/genética , História Antiga , Humanos , Lactente , Lipídeos/análise , Mycobacterium tuberculosis/genética , Paleopatologia , Síria , Tuberculose Osteoarticular/genética , Adulto Jovem
5.
Tuberculosis (Edinb) ; 95 Suppl 1: S35-41, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25771204

RESUMO

Macromorphological analysis of skeletons, from 20 selected graves of the 8th century AD Bélmegyer-Csömöki domb, revealed 19 cases of possible skeletal tuberculosis. Biomolecular analyses provided general support for such diagnoses, including the individual without pathology, but the data did not show coherent consistency over the range of biomarkers examined. Amplification of ancient DNA fragments found evidence for the Mycobacterium tuberculosis complex DNA only in five graves. In contrast, varying degrees of lipid biomarker presence were recorded in all except two of the skeletons, though most lipid components appeared to be somewhat degraded. Mycobacterial mycolic acid biomarkers were absent in five cases, but the weak, possibly degraded profiles for the remainder were smaller and inconclusive for either tuberculosis or leprosy. The most positive lipid biomarker evidence for tuberculosis was provided by mycolipenic acid, with 13 clear cases, supported by five distinct possible cases. Combinations of mycocerosic acids were present in all but three graves, but in one case a tuberculosis-leprosy co-infection was indicated. In two specimens with pathology, no lipid biomarker evidence was recorded, but one of these specimens provided M. tuberculosis complex DNA fragments.


Assuntos
Tuberculose Osteoarticular/patologia , Adulto , Idoso , Biomarcadores/análise , Cromatografia Líquida de Alta Pressão , DNA Bacteriano/genética , Feminino , História Medieval , Humanos , Hungria , Lipídeos/análise , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/genética , Ácidos Micólicos/análise , Técnicas de Amplificação de Ácido Nucleico , Paleopatologia , Reação em Cadeia da Polimerase , Tuberculose Osteoarticular/genética , Tuberculose Osteoarticular/história , Adulto Jovem
6.
J Org Chem ; 61(22): 7927-7932, 1996 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11667754

RESUMO

First-order solvolysis rate constants are reported for solvolyses of acetyl chloride in methanol and MeOD, and in binary aqueous mixtures with acetone, acetonitrile, ethanol, methanol, and trifluoroethanol at 0 degrees C. Product selectivities (S = [MeCOOR]/[MeCOOH] x [water]/[alcohol]) are reported for solvolyses in ethanol/ and methanol/water at 0 degrees C. Solvolyses of acetyl chloride show a high sensitivity to changes in solvent ionizing power, consistent with C-Cl bond cleavage. As the solvent is varied from pure ethanol (or methanol) to water, S values and rate-rate profiles show no evidence for the change in reaction channel observed for solvolyses of benzoyl and trimethylacetyl chlorides. However, using rate ratios in 40% ethanol/water and 97% trifluoroethanol/water (solvents of similar ionizing power but different nucleophilicities) to compare sensitivities to nucleophilic attack, solvolyses of acetyl chloride are over 20-fold more sensitive to nucleophilic attack than benzoyl chloride. The solvent isotope effect of 1.29 (MeOH/MeOD) for acetyl chloride is similar to that for p-methoxybenzoyl chloride (1.22) and is lower than for benzoyl chloride (1.55). Second-order rate constants for aminolyses of acetyl chloride with m-nitroaniline in methanol at 0 degrees C show that acetyl chloride behaves similarly to p-methoxybenzoyl chloride, whereas benzoyl chloride is 40-fold more sensitive to the added amine. The results indicate mechanistic differences between solvolyses of acetyl and benzoyl chlorides, and an S(N)2 mechanism is proposed for solvolyses and aminolyses by m-nitroaniline of acetyl chloride (i.e. these reactions are probably not carbonyl additions, but a strong sensitivity to nucleophilic attack accounts for their high rates).

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