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1.
Nat Prod Res ; 36(7): 1883-1888, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32820642

RESUMO

The supercritical fluid extraction (SFE) of volatile and fixed oil from milled parsley (Petroselinum crispum L.) seeds, using CO2 as solvent, is presented in this study. Extraction experiments were carried out in two steps: at pressures of (90 or 300) bar and temperature of 40 °C. The first extraction step, performed at 90 bar, produced a volatile fraction mainly formed by apiole (82.1%) and myristicin (11.4%). The volatile oil yield was 2.6% by weight of the charge. The second extraction step, carried out at 300 bar produced a fixed oil at a yield of 0.4% by weight. The most represented fatty acids in P. crispum fixed oil were 18:1 n-12 (49.9%), 18:2 n-6 (18.2%), 18:1 n-9 (11.8%), and 16:0 (7.4%). In particular, the unsaturated fatty acids 18:1 n-12 and 18:1 n-9 averaged 182.2 mg/g and 92.1 mg/g of oil extract, respectively. The quality of the oils extracted by SFE, in terms of its chemical composition, was compared to the oils obtained by hydrodistillation (HD) in a Clevenger apparatus and by solvent extraction (SE) using n-hexane in a Soxhlet apparatus. The antioxidant properties were determined by means of the ABTS assay. The results indicated that the fixed oil possessed low antioxidant activity (EC50 = 0.4 mg/mL) and the volatile oil had no antioxidant activity. The total phenolic content, expressed as concentration of gallic acid (gallic acid equivalent, GAE), of the fixed oil was 1.5 mg/g. The fixed oil found to have inhibitory effects against α-glucosidase, the volatile oil is active on acetylcholinesterase (AChE), tyrosinase, and α-glucosidase. Both samples have weak inhibitory activity on α-amylase and no activity on butyrylcholinesterase (BChE).


Assuntos
Cromatografia com Fluido Supercrítico , Óleos Voláteis , Acetilcolinesterase/análise , Butirilcolinesterase/análise , Dióxido de Carbono/química , Cromatografia com Fluido Supercrítico/métodos , Óleos Voláteis/química , Petroselinum , Óleos de Plantas/química , Sementes/química
2.
Sci Rep ; 6: 28562, 2016 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-27340122

RESUMO

The sperm whale carries a hypertrophied nose that generates powerful clicks for long-range echolocation. However, it remains a conundrum how this bizarrely shaped apex predator catches its prey. Several hypotheses have been advanced to propose both active and passive means to acquire prey, including acoustic debilitation of prey with very powerful clicks. Here we test these hypotheses by using sound and movement recording tags in a fine-scale study of buzz sequences to relate the acoustic behaviour of sperm whales with changes in acceleration in their head region during prey capture attempts. We show that in the terminal buzz phase, sperm whales reduce inter-click intervals and estimated source levels by 1-2 orders of magnitude. As a result, received levels at the prey are more than an order of magnitude below levels required for debilitation, precluding acoustic stunning to facilitate prey capture. Rather, buzzing involves high-frequency, low amplitude clicks well suited to provide high-resolution biosonar updates during the last stages of capture. The high temporal resolution helps to guide motor patterns during occasionally prolonged chases in which prey are eventually subdued with the aid of fast jaw movements and/or buccal suction as indicated by acceleration transients (jerks) near the end of buzzes.


Assuntos
Comportamento Predatório/fisiologia , Cachalote/fisiologia , Acústica , Animais , Ecolocação/fisiologia , Som , Espectrografia do Som/métodos , Vocalização Animal/fisiologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-23986787

RESUMO

BACKGROUND: Antidepressant (AD) drugs are effective in the short term treatment of fibromyalgia (FM). It may be useful to study the long-term impact of AD on patients with FM. METHODS: One-year follow-up study on 23 females with FM divided into groups on AD (ADg-N=7), and not taking AD (NADg-N=11). Evaluation at t1 and at the end (t2) with the Fibromyalgia Impact Questionnaire (FIQ); at t2 with: SCID-IV; Mood Disorder Questionnaire (MDQ); Short Form-12; Hamilton Depression Rating Scale (HAM-D); Functioning Assessment Short Test (FAST). RESULTS: After a year the AD group showed a worst impact of the disease by FIQ (p=0.017), worsened quality of life by SF-12 (p<0.01), and disability linked to bipolar symptoms by FAST (p=0.05). About 40% of the sample was screened positive at MDQ without difference in the two groups. The patients who recovered from a depressive episode did not differ between ADg and NADg (20% vs 33.3%), and were fewer than expected from the literature (40-60%). The HAM-D score at the end of the trial was worse in the ADg (p<0.03). LIMITATIONS: Observational research on few patients, not specifically designed to test the hypothesis. The results have a heuristic value only. DISCUSSION: The results should be read in the light of the high prevalence of patients screened positive for Bipolar Disorders and of the well-known poor response of the mood symptoms to antidepressants in Bipolar Depression. The deterioration in the long-term management of FM patients following AD treatments suggests the need for new and robust studies.

4.
Clin Biochem ; 46(1-2): 37-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23000315

RESUMO

OBJECTIVE: To evaluate serum purine metabolite concentrations in patients affected by fibromyalgia syndrome (FMS) and the relationships between their levels and FM clinical parameters. DESIGN AND METHODS: Serum purine levels were quantified using LC/UV-vis in 22 fibromyalgic females (according to the American College of Rheumatology classification criteria) and 22 healthy females. RESULTS: Significantly higher serum inosine, hypoxanthine and xanthine levels (p<0.001) and significantly lower serum adenosine (p<0.05) were detected in the FMS patients vs healthy controls. Our data show a negative correlation between adenosine and Fibromyalgia Impact Questionnaire (FIQ). CONCLUSIONS: Study results suggest that purines, in particular adenosine and inosine, may be involved in pain transmission in fibromyalgia.


Assuntos
Fibromialgia/sangue , Purinas/metabolismo , Adenosina/sangue , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Fibromialgia/etiologia , Humanos , Hipoxantina/sangue , Inosina/sangue , Pessoa de Meia-Idade , Purinas/sangue , Valores de Referência , Inquéritos e Questionários , Xantina/sangue
5.
Biopolymers ; 87(1): 85-92, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17554783

RESUMO

The synthetic peptide Vitr-p-13 (YPIVGQELLGAIK-NH(2)), derived from the bacterial dimeric Vitreoscilla haemoglobin (VHb) in the position 95-107, is characterized by a pre-eminent "statistical coil" conformation in water as demonstrated by CD experiments and long time-scale MD simulations. In particular, Vitr-p-13 does not spontaneously adopt an alpha-helix folding in water, but it is rather preferentially found in beta-hairpin-like conformations. Long time-scale MD simulations have also shown that Vitr-p-13 displays a "topological-trigger" which initiates alpha-helix folding within residues 7-10, exactly like seen in the temporins, a group of linear, membrane-active antimicrobial peptides of similar length. At variance with temporins, in Vitr-p-13 such a process is energetically very demanding (+10 kJ/mol) in water at 300 K, and the peptide was found to be unable to bind model membranes in vitro and was devoid of antimicrobial activity. The present results, compared with previous studies on similar systems, strengthen the hypothesis of the requirement of a partial folding when still in aqueous environment to allow a peptide to interact with cell-membranes and eventually exert membrane perturbation-related antibiotic effects on target microbial cells.


Assuntos
Proteínas de Bactérias/química , Hemoglobinas/química , Modelos Moleculares , Peptídeos/química , Dobramento de Proteína , Vitreoscilla/química , Proteínas de Bactérias/metabolismo , Membrana Celular/química , Membrana Celular/metabolismo , Hemoglobinas/metabolismo , Peptídeos/metabolismo , Ligação Proteica , Estrutura Secundária de Proteína , Relação Estrutura-Atividade , Hemoglobinas Truncadas , Vitreoscilla/metabolismo
6.
Eur J Biochem ; 268(14): 4104-11, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11454005

RESUMO

The Gymnothorax unicolor hemoglobin system is characterized by two components, called cathodic and anodic on the basis of their isoelectric point, which were separated by ion-exchange chromatography. The oxygen-binding properties of the purified components were studied in the absence and presence of chloride and/or GTP or ATP in the pH range 6.5-8.0. Stripped cathodic hemoglobin showed a small reverse Bohr effect, high oxygen affinity, and low co-operativity; the addition of chloride only caused a small decrease in oxygen affinity. In the presence of GTP or ATP, the oxygen affinity was dramatically reduced, the co-operativity increased, and the reverse Bohr effect abolished. Stripped anodic hemoglobin is characterized by both low oxygen affinity and co-operativity, and displayed a normal Bohr effect; the addition of chloride increased co-operativity, whereas ATP and GTP significantly modulated oxygen affinity at acidic pH values, enhancing the Bohr effect and giving rise to the Root effect. The complete amino-acid sequences of the alpha and beta chains of both hemoglobins were established; the molecular basis of the functional properties of the hemoglobins is discussed in the light of the primary structure and compared with those of other fish hemoglobins.


Assuntos
Peixes , Hemoglobinas/fisiologia , Regulação Alostérica , Sequência de Aminoácidos , Animais , Hemoglobinas/química , Dados de Sequência Molecular , Oxigênio/metabolismo , Fosfatos/metabolismo , Homologia de Sequência de Aminoácidos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
7.
Eur J Biochem ; 268(11): 3313-20, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11389734

RESUMO

A study was made of the haemoglobin (Hb) system from the Sardinian dwarf horse (Equus caballus jara), one of the last surviving wild horse species in Europe. The oxygen binding properties of the whole haemolysate and of the four different horse Hbs, separated by ion-exchange chromatography, were studied with special regard to the effect of chloride, 2,3-diphosphoglycerate and lactate. Results indicate that no significant functional differences exist between the four Hb components of horse haemolysate. Moreover, the molecular basis of the intrinsically low oxygen affinity and of the weak interaction of horse Hb with 2,3-diphosphoglycerate is discussed in the light of the primary structure of the molecule and of the results of a computer modelling approach. On these bases, it is suggested that the A1 (Thr-->Ser) and A2 (Pro-->Gly) substitutions observed in the beta chains from horse Hb may be responsible for the displacement of the A helix that is known to be a key structural feature of those Hbs that display an altered interaction with 2,3-diphosphoglycerate as compared with human Hb.


Assuntos
Hemoglobinas/genética , Cavalos/genética , Adulto , Animais , Sítios de Ligação , Proteínas de Transporte/química , Simulação por Computador , Eritrócitos/química , Haplótipos , Hemoglobinas/isolamento & purificação , Cavalos/sangue , Humanos , Concentração de Íons de Hidrogênio , Focalização Isoelétrica , Modelos Moleculares , Proteínas do Tecido Nervoso/química , Fenótipo
8.
Biochem J ; 346 Pt 1: 193-9, 2000 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10657257

RESUMO

Haemoglobin (Hb) J-Sardegna [alpha50(CE8)His-->Asp] is a haemoglobin variant characteristic of subjects from the island of Sardinia. Here we report a study of the functional properties of both fetal and adult Hb J-Sardegna. The results indicate that adult Hb J-Sardegna displays an oxygen affinity that is higher than that of adult Hb only in the presence of 2,3-diphosphoglycerate (2,3-DPG). On the contrary, at 20 degrees C, the oxygen affinity of fetal Hb J-Sardegna is identical to that of normal fetal haemoglobin, both in the presence and in the absence of 2,3-DPG. A significant difference between these two systems (i.e. a higher oxygen affinity of fetal Hb J-Sardegna) shows up very clearly only when temperature is increased to 37 degrees C. Hence in fetal Hb, the main effect of the amino acid substitution is a decrease in the overall enthalpy change of oxygenation. The results outline the role of the alpha(1)-beta(1) interface in assessing the thermodynamics of oxygen binding. The functional properties of both adult and fetal Hb J-Sardegna have been interpreted at the structural level in light of the results obtained by a computational modelling approach performed in comparison with HbA and Hb Aichi, a variant characterized by a different mutation [alpha50(CE8)His-->Arg] at the same position.


Assuntos
Envelhecimento/sangue , Substituição de Aminoácidos/genética , Sangue Fetal/química , Hemoglobina J/química , Hemoglobina J/metabolismo , Modelos Moleculares , 2,3-Difosfoglicerato/metabolismo , Adulto , Arginina/genética , Ácido Aspártico/genética , Sítios de Ligação , Simulação por Computador , Cristalografia por Raios X , Variação Genética/genética , Hemoglobina J/genética , Hemoglobinas Anormais/química , Hemoglobinas Anormais/genética , Hemoglobinas Anormais/metabolismo , Histidina/genética , Humanos , Concentração de Íons de Hidrogênio , Recém-Nascido , Oxigênio/metabolismo , Temperatura , Termodinâmica , Fatores de Tempo
9.
Eur J Biochem ; 260(3): 667-71, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10102994

RESUMO

A study of the functional properties of haemoglobin from red deer (Cervus elaphus) whose habitat varies over a wide range of latitude, was performed. The oxygen-binding properties of the most common haemoglobin phenotype from the species living in Sardinia were examined with particular attention to the effect of pH, chloride, 2, 3-bisphosphoglycerate and temperature. Results indicate that red deer haemoglobin, like all haemoglobins from ruminants so far examined, is characterized by a low intrinsic oxygen affinity, with chloride being its main physiological modulator in vivo. The functional results and the low temperature sensitivity of the oxygen affinity are discussed in the light of the amino acid sequence of closely related ruminant haemoglobins.


Assuntos
Adaptação Fisiológica/fisiologia , Altitude , Clima Frio , Cervos/fisiologia , Hemoglobinas/fisiologia , Regulação Alostérica , Animais , Cervos/sangue , Eletroforese em Gel de Poliacrilamida , Evolução Molecular , Hemoglobinas/química , Focalização Isoelétrica , Oxigênio/metabolismo
10.
Comp Biochem Physiol B Biochem Mol Biol ; 117(3): 417-20, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9253179

RESUMO

The functional properties of Hb B of the wild European mouflon (Ovis gmelini musimon), Hb B of domestic sheep (Ovis aries), and Hb C isolated from anemic mouflon were investigated. Mouflon and sheep Hbs appear to be very similar in their response to organic anions and protons, whereas sheep Hb B displays an oxygen affinity lower than that of mouflon Hb B and sheep Hb A. Mouflon Hb B and Hb C, like sheep Hb A and Hb C, have similar efficiencies in transporting oxygen to the tissues. As in other ruminant Hbs, the effect of temperature on the oxygen affinity is slight. Data suggest that mouflon Hb B is not only structurally, but even functionally, more similar to sheep Hb A than to sheep Hb B.


Assuntos
Hemoglobina A/metabolismo , Hemoglobina C/metabolismo , Hemoglobinas/metabolismo , Ovinos/sangue , Animais , Concentração de Íons de Hidrogênio , Oxiemoglobinas/metabolismo , Fenótipo , Temperatura , Termodinâmica
11.
Ital J Biochem ; 46(1): 7-14, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9247845

RESUMO

A study was made of the Hb phenotype of the Sardinian dwarfhorse (Equus caballus jara), one of the last surviving wild horse species in Europe. Hb haplotypes and their frequencies were found to be similar to those described in the Arabian horse (BI = 0.551, BII = 0.389, A = 0.036, V = 0.015), which suggests possible introduction onto the island from North Africa. The oxygen binding properties of the whole hemolysates and of the four different horse Hbs, separated by ion-exchange chromatography, were considered with regard to the effect of chloride, 2,3-bisphosphoglycerate and lactate. Results indicate that no differences exist in the four components that characterize horse Hb. The molecular basis of the intrinsically low oxygen affinity and of the weak interaction of horse Hb with 2,3-bisphosphoglycerate is discussed in the light of the primary structure of the molecule.


Assuntos
Hemoglobinas/genética , Cavalos/genética , Oxigênio/sangue , Polimorfismo Genético , Animais , Nanismo/genética , Frequência do Gene , Haplótipos , Hemólise , Humanos , Itália , Modelos Lineares , Fenótipo , Ligação Proteica , Especificidade da Espécie
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