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1.
J Food Sci Technol ; 53(1): 501-10, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26787969

RESUMO

Lack of nutrients in cooking water, high energetic costs, high water consumption and recycling are some drawbacks of vegetable blanching. Those disadvantages could be bypassed using microwave blanching. Three blanching methods (microwave, boiling water and steaming) were compared in this study in order to determine their effects on some functional properties of broccoli. In addition, the thermal damage on broccoli colour was evaluated. The effectiveness of each blanching process was performed measuring the lost of peroxidase activity, that results more rapidly in microwaves and steam treatments (50 and 60 s respectively) than in boiling water treatment (120 s). The colour indexes did not allow to discriminate a significant difference among treatments. The increase of treatment time caused a vitamin C decrease in samples blanched by boiling water and steam; this trend was not observed in microwaved samples. The phenols content did not significantly vary depending both on type and on time of treatment.

2.
Food Res Int ; 173(Pt 1): 113265, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803578

RESUMO

Robots in manufacturing alleviate hazardous environmental conditions, reduce the physical/mental stress of the workers, maintain high precision for repetitive movements, reduce errors, speed up production, and minimize production costs. Although robots have pervaded many industrial sectors and domestic environments, the experiments in the food sectors are limited to pick-and-place operations and meat processing while we are assisting new attention in gastronomy. Given the great performances of the robots, there would be many other intriguing applications to explore which could usher the transition to precision food manufacturing. This review wants open thoughts and opinions on the use of robots in different food operations. First, we reviewed the recent advances in common applications - e.g. novel sensors, end-effectors, and robotic cutting. Then, we analyzed the use of robots in other operations such as cleaning, mixing/kneading, dough manipulation, precision dosing/cooking, and additive manufacturing. Finally, the most recent improvements of robotics in gastronomy with their use in restaurants/bars and domestic environments, are examined. The comprehensive analyses and the critical discussion highlighted the needs of further scientific understanding and exploitation activities aimed to fill the gap between the laboratory-scale results and the validation in the relevant environment.


Assuntos
Robótica , Humanos , Robótica/métodos , Indústria Alimentícia , Culinária , Restaurantes
3.
Crit Rev Food Sci Nutr ; 51(10): 955-64, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21955094

RESUMO

As is well known, pasteurization treatments are not sufficient for destroying heat resistance of spore forming microorganisms, which are prevented from germination and growing by pH reducing. So, the acidification process becomes one of the most important pre-treatments for the canning industry. It is commonly applied before pasteurization treatment with the purpose of inhibiting spore germination and for reducing heat resistance of the microorganism, thereby allowing to reduce the time or temperature values of the heat treatment. With the aim to reduce the pH of vegetables several techniques are available but their application is not easy to plan. Often, industries define operative conditions only on the basis of empirical experience, thus increasing the risk of microbial growth or imparting an unpleasant sour taste. With the aim of highlighting the correct plan and management of acidification treatments to reach safety without degrading quality of canned fruit and vegetables, the topics that are reviewed and discussed are the effects of low pH on heat resistance of the most important microorganisms, acidification techniques and significant process variables, the effect of low pH on sensorial properties, and future trends.


Assuntos
Contaminação de Alimentos/prevenção & controle , Manipulação de Alimentos/métodos , Alimentos em Conserva/análise , Verduras , Qualidade de Produtos para o Consumidor , Microbiologia de Alimentos , Conservação de Alimentos/métodos , Humanos , Concentração de Íons de Hidrogênio , Pasteurização , Esporos Bacterianos/crescimento & desenvolvimento , Temperatura
4.
Food Res Int ; 106: 666-676, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29579973

RESUMO

3D printing technology was employed to obtain snacks with a designed cylindrical geometry from wheat flour dough enriched by ground larvae of Yellow mealworms (Tenebrio molitor) as novel source of proteins. The main microstructural features, overall quality, and nutritional attributes were studied as a function of formulation, time and temperature of baking. The addition of ground insects up to 20 g/100 g (d.b.) resulted in softer dough. This caused an overflow in dough deposition producing the increase in diameter, height and weight of snacks. Baking conditions did not alter the overall aspect of the snacks, but modification of the main dimensional and microstructure attributes were observed due to the better water evaporation. The optimization of baking conditions found that 22 min and 200 °C allowed obtaining a maximum desirability of 0.693. Baked in these conditions, the printed snacks enriched with 10 and 20% of ground insects significantly increased the total essential amino acid, from 32.5 (0% insects) to 38.2 and 41.3 g/100 g protein, respectively. The protein digestibility corrected amino acid score increased from 41.6 to 65.2 from 0 to 20% insect enrichment, with lysine and methionine + cysteine being the respective limiting amino acid. Our results evidenced the rational promotion of insects based on nutritional arguments and validated the use of 3D printing as technology to manufacture innovative printed snacks without adverse impact on technological quality.


Assuntos
Proteínas Alimentares/análise , Grão Comestível/química , Farinha/análise , Manipulação de Alimentos/métodos , Alimentos Fortificados/análise , Proteínas de Insetos/análise , Valor Nutritivo , Impressão Tridimensional , Lanches , Tenebrio/química , Triticum/química , Aminoácidos/análise , Animais , Culinária , Proteínas Alimentares/normas , Digestão , Grão Comestível/normas , Farinha/normas , Alimentos Fortificados/normas , Temperatura Alta , Proteínas de Insetos/normas , Conformação Proteica , Controle de Qualidade
5.
Neuropharmacology ; 52(6): 1366-77, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17397881

RESUMO

In the current study, we have evaluated the ability of substance P (SP) and other neurokinin 1 receptor (NK1) agonists to protect, in a dose- and time-dependent manner, primary cultures of rat cerebellar granule cells (CGCs) from serum and potassium deprivation-induced cell death (S-K5). We also established the presence of SP high affinity NK1 transcripts and the NK1 protein localization in the membrane of a sub-population of CGCs. Moreover, SP significantly and dose-dependently reduced the Akt 1/2 and Erk1/2 dephosphorylation induced by S-K5 conditions, as demonstrated by Western blot analysis. Surprisingly, in SP-treated CGCs caspase-3 activity was not inhibited, while the calpain-1 activity was moderately reduced. Corroborating this result, SP blocked calpain-mediated cleavage of tau protein, as demonstrated by the reduced appearance of a diagnostic fragment of 17 kDa by Western blot analysis. In addition, SP induced a significant reduction of the delayed rectifier K+ currents (Ik) in about 42% of the patched neurons, when these were evoked with depolarizing potential steps. Taken together, the present results demonstrate that the activation of NK1 receptors expressed in CGCs promote the neuronal survival via pathways involving Akt and Erk activation and by inhibition of Ik which can contribute to the neuroprotective effect of the peptide.


Assuntos
Cerebelo/efeitos dos fármacos , Canais de Potássio de Retificação Tardia/fisiologia , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Fármacos Neuroprotetores , Substância P/farmacologia , Animais , Western Blotting , Calpaína/antagonistas & inibidores , Caspases/metabolismo , Cerebelo/citologia , Grânulos Citoplasmáticos/fisiologia , Canais de Potássio de Retificação Tardia/efeitos dos fármacos , Eletrofisiologia , Ativação Enzimática/efeitos dos fármacos , Imuno-Histoquímica , Microscopia de Contraste de Fase , Proteína Oncogênica v-akt/fisiologia , Técnicas de Patch-Clamp , Potássio/fisiologia , Ratos , Ratos Wistar , Receptores da Neurocinina-1/efeitos dos fármacos , Receptores da Neurocinina-1/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Substância P/análogos & derivados , Taquicininas/agonistas
7.
Neuropharmacology ; 117: 134-148, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28163105

RESUMO

Nerve Growth Factor (NGF) is being considered as a therapeutic candidate for Alzheimer's disease. However, the development of an NGF-based therapy is limited by its potent pain activity. We have developed a "painless" derivative form of human NGF (NGF61/100), characterized by identical neurotrophic properties but a reduced nociceptive sensitization activity in vivo. Here we characterized the response of rat dorsal root ganglia neurons (DRG) to the NGF derivative NGF61/100, in comparison to that of control NGF (NGF61), analyzing the expression of noxious pro-nociceptive mediators. NGF61/100 displays a neurotrophic activity on DRG neurons comparable to that of control NGF61, despite a reduced activation of PLCγ, Akt and Erk1/2. NGF61/100 does not differ from NGF61 in its ability to up-regulate Substance P (SP) and Calcitonin Gene Related Peptide (CGRP) expression. However, upon Bradykinin (BK) stimulation, NGF61/100-treated DRG neurons release a much lower amount of SP and CGRP, compared to control NGF61 pre-treated neurons. This effect of painless NGF is explained by the reduced up-regulation of BK receptor 2 (B2R), respect to control NGF61. As a consequence, BK treatment reduced phosphorylation of the transient receptor channel subfamily V member 1 (TRPV1) in NGF61/100-treated cultures and induced a significantly lower intracellular Ca2+ mobilization, responsible for the lower release of noxious mediators. Transcriptomic analysis of DRG neurons treated with NGF61/100 or control NGF allowed identifying a small number of nociceptive-related genes that constitute an "NGF pain fingerprint", whose differential regulation by NGF61/100 provides a strong mechanistic basis for its selective reduced pain sensitizing actions.


Assuntos
Fator de Crescimento Neural/efeitos adversos , Fator de Crescimento Neural/farmacologia , Dor/induzido quimicamente , Fragmentos de Peptídeos/efeitos adversos , Células Receptoras Sensoriais/citologia , Animais , Bradicinina/farmacologia , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Cálcio/metabolismo , Gânglios Espinais/metabolismo , Perfilação da Expressão Gênica , Humanos , Dor/metabolismo , Fragmentos de Peptídeos/farmacologia , Cultura Primária de Células , Ratos , Receptores da Bradicinina/metabolismo , Substância P/metabolismo , Canais de Cátion TRPV/metabolismo , Regulação para Cima/efeitos dos fármacos
8.
Cell Death Discov ; 2: 16050, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27551538

RESUMO

A change in the delicate equilibrium between apoptosis and survival regulates the neurons fate during the development of nervous system and its homeostasis in adulthood. Signaling pathways promoting or protecting from apoptosis are activated by multiple signals, including those elicited by neurotrophic factors, and depend upon specific transcriptional programs. To decipher the rescue program induced by substance P (SP) in cerebellar granule neurons, we analyzed their whole-genome expression profiles after induction of apoptosis and treatment with SP. Transcriptional pathways associated with the survival effect of SP included genes encoding for proteins that may act as pharmacological targets. Inhibition of one of these, the Myc pro-oncogene by treatment with 10058-F4, reverted in a dose-dependent manner the rescue effect of SP. In addition to elucidate the transcriptional mechanisms at the intersection of neuronal apoptosis and survival, our systems biology-based perspective paves the way towards an innovative pharmacology based on targets downstream of neurotrophic factor receptors.

9.
Biochim Biophys Acta ; 1033(3): 318-23, 1990 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-2317508

RESUMO

The peptide fraction extracted by methanol from the skin of Rana esculenta, a species widely distributed in Western Europe, was investigated. The pharmacological activity found in the extract is attributable to the presence of authentic bradykinin, together with a shorter, partially active version of this molecule, des-Arg9-bradykinin. Also the bradykinin fragment 1-7 has been isolated, but it was inactive in our bioassay system. Moreover, a family of hydrophobic peptides has been purified and characterized, which appeared devoid of pharmacological activities when tested on smooth muscle preparations, but were provided with hemolytic activities.


Assuntos
Peptídeos/isolamento & purificação , Rana esculenta/metabolismo , Pele/análise , Sequência de Aminoácidos , Animais , Bradicinina/análogos & derivados , Bradicinina/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Hemólise/efeitos dos fármacos , Humanos , Dados de Sequência Molecular , Peptídeos/farmacologia , Conformação Proteica
10.
Eur J Histochem ; 49(1): 87-92, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15823799

RESUMO

We previously demonstrated that exogenously administered neurokinin A and neurokinin B, but not substance P, increased the sensitivity of cultured cerebellar granule neurons (CGNs) to glutamate. In the present study, the presence of tachykinin neuropeptides in CGNs was tested by confocal-based immunofluorescence. We found that neurokinin A and neurokinin B are present in CGNs but absent in astrocytes while substance P is abundant in astrocytes but absent in CGNs. It is postulated that the different localization of tachykinin neuropeptides in CGNs and astroglial cells has a physiological role in the modulation of excitatory transmission.


Assuntos
Cerebelo/química , Neurônios/química , Neuropeptídeos/análise , Taquicininas/análise , Animais , Especificidade de Anticorpos , Astrócitos/química , Astrócitos/citologia , Astrócitos/metabolismo , Células Cultivadas , Cerebelo/citologia , Cerebelo/metabolismo , Grânulos Citoplasmáticos , Imunofluorescência , Imuno-Histoquímica , Microscopia Confocal , Neurocinina A/análise , Neurocinina A/biossíntese , Neurocinina B/análise , Neurocinina B/biossíntese , Neurônios/citologia , Neurônios/metabolismo , Neuropeptídeos/biossíntese , Ratos , Substância P/análise , Substância P/biossíntese , Taquicininas/biossíntese
11.
J Agric Food Chem ; 63(8): 2321-7, 2015 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-25665600

RESUMO

The changes in chemical attributes and aromatic profile of espresso coffee (EC) were studied taking into account the extraction time and grinding level as independent variables. Particularly, using an electronic nose system, the changes of the global aromatic profile of EC were highlighted. The results shown as the major amounts of organic acids, solids, and caffeine were extracted in the first 8 s of percolation. The grinding grade significantly affected the quality of EC probably as an effect of the particle size distribution and the percolation pathways of water through the coffee cake. The use of an electronic nose system allowed us to discriminate the fractions of the brew as a function of the percolation time and also the regular coffee obtained from different grinding grades. Particularly, the aromatic profile of a regular coffee (25 mL) was significantly affected by the grinding level of the coffee grounds and percolation time, which are two variables under the control of the bar operator.


Assuntos
Coffea/química , Café/química , Manipulação de Alimentos/métodos , Compostos Orgânicos Voláteis/química , Nariz Eletrônico , Temperatura Alta , Odorantes/análise , Tamanho da Partícula
12.
FEBS Lett ; 429(1): 41-3, 1998 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-9657380

RESUMO

We have isolated a cDNA encoding a precursor of dermorphin from the skin of Pachymedusa dacnicolor. Besides four copies of this opioid peptide, the deduced sequence also contains the genetic information for a novel peptide Tyr-Ile-Phe-His-Leu-Met-Asp-NH2. This differs from Met-deltorphin by the presence of Ile at position 2. In a related precursor from the skin of Agalychnis annae, the sequence of this peptide is in the 3'-untranslated region of the cloned cDNA. From earlier results we predict that in skin peptides the second residue is D-allo-Ile. We have synthesized this and related peptides with different D-amino acids, and determined their delta agonist activity. The peptide with D-nor-Leu binds with high affinity to delta receptors, while that with D-allo-Ile is about 100 times less active.


Assuntos
Anuros/genética , DNA Complementar/análise , Oligopeptídeos/genética , Peptídeos Opioides/genética , Sequência de Aminoácidos , Animais , Dados de Sequência Molecular , Oligopeptídeos/efeitos dos fármacos , Peptídeos Opioides/química , Peptídeos Opioides/farmacologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
13.
FEBS Lett ; 302(2): 151-4, 1992 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-1633846

RESUMO

Skin extracts of South American hylid frogs of the subfamily Phyllomedusinae contain dermorphins and deltorphins, opioid heptapeptides highly selective for either mu or delta receptors. In all these peptides, a D-amino acid is present in the second position. The structure of the precursors for Ala-deltorphins was recently deduced from cloned cDNAs derived from skin of Phyllomedusa bicolor (Richter et al. (1990) Proc. Natl. Acad. Sci. USA 87, 4836-4839). From the amino acid sequence of these precursors, the existence of three peptides related to dermorphin could be predicted. From methanol extracts of skin of Ph. bicolor we have isolated two of these peptides, [Lys7]dermorphin-OH and [Trp4,Asn7]dermorphin-OH. The biological activity of these new dermorphins and their amidated counterparts is presented.


Assuntos
Anuros , Oligopeptídeos/isolamento & purificação , Pele/química , Sequência de Aminoácidos , Animais , Cromatografia Líquida de Alta Pressão , Cobaias , Intestino Delgado/fisiologia , Masculino , Camundongos , Dados de Sequência Molecular , Contração Muscular/efeitos dos fármacos , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Peptídeos Opioides , Ducto Deferente/fisiologia
14.
Mol Biochem Parasitol ; 111(1): 153-61, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11087925

RESUMO

A molecular assay has been developed for the specific detection and genetic characterisation of Plasmodium falciparum gametocytes in the blood of malaria infected individuals. The assay is based on the reverse transcription and polymerase chain reaction (RT-PCR) amplification of the messenger RNA of gene pfg377, a sexual-stage specific transcript abundantly produced in maturing gametocytes. The gene contains four regions of repetitive sequences, of which region 3 was shown to be the most polymorphic in laboratory clones and field isolates of the parasite. Analysis of samples of malaria infected blood by RT-PCR specific for region 3 has enabled identification of multiple gametocyte-producing clones within single infections. The assay is able to detect gametocytes below the threshold of microscopic detection, and is highly specific for its gametocyte targets also in the presence of a vast excess of asexual forms.


Assuntos
Genes de Protozoários , Malária Falciparum/parasitologia , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alelos , Animais , Variação Genética , Genótipo , Humanos , Plasmodium falciparum/classificação , Plasmodium falciparum/isolamento & purificação , Polimorfismo Genético , Proteínas de Protozoários/genética , Sequências Repetitivas de Ácido Nucleico , Sensibilidade e Especificidade
15.
Neuropharmacology ; 28(4): 319-28, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2747845

RESUMO

Semi-purified extracts of the skin of the Australian myobatrachid frog Pseudophryne coriacea (PS)displayed striking, reversible and, in part, dose-dependent effects on the systemic blood pressure of the rat and other experimental animals, as well as on the rat heart. The blood pressure response in the rat consisted typically in an abrupt, short-lasting fall, followed by a conspicuous, more persistent rise. The fall in pressure was abolished by atropine and potentiated by physostigmine, indicating a cholinergic mechanism; rise was abolished by prazosin and guanethidine, suggesting a release of catecholamines from adrenergic nerve terminals in the vasculature. Tachyphylaxis was the obvious result of exhaustion of stores of catecholamines. On the heart, as shown in the electrocardiographic tracings, PS produced a variety of rhythm disorders, attributable both to the release of aminergic transmitters and to a direct effect on the myocardium. Whereas the pressure and electrocardiographic responses were virtually unaffected by calcium channel antagonists and agonists, all the effects of PS were sharply reduced or completely abolished by the sodium channel blocker tetrodotoxin. This suggests that activation of sodium channels may play a role in the mechanism of action of PS. However, the exact nature of ionic flux(es)influenced by the extract of frog skin remains to be established.


Assuntos
Alcaloides/análise , Pressão Sanguínea/efeitos dos fármacos , Coração/efeitos dos fármacos , Indolizinas , Piperidinas , Fenômenos Fisiológicos da Pele , Extratos de Tecidos/farmacologia , Adrenalectomia , Animais , Anuros , Arritmias Cardíacas/fisiopatologia , Fármacos do Sistema Nervoso Autônomo/farmacologia , Cálcio/fisiologia , Cães , Eletrocardiografia , Cobaias , Técnicas In Vitro , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Coelhos , Ratos , Ratos Endogâmicos , Salivação/efeitos dos fármacos , Sódio/fisiologia
16.
J Med Chem ; 42(3): 400-4, 1999 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-9986710

RESUMO

In the present paper we describe the synthesis of some dermorphin and deltorphin analogues beta-O- and alpha-C-glycosylated on the C-terminal amino acid residue and report their opioid receptor affinity and selectivity as well as their analgesic potency after subcutaneous injection in mice.


Assuntos
Analgésicos Opioides/síntese química , Oligopeptídeos/síntese química , Sequência de Aminoácidos , Analgésicos Opioides/química , Analgésicos Opioides/farmacologia , Animais , Glicosilação , Cobaias , Técnicas In Vitro , Injeções Subcutâneas , Masculino , Camundongos , Músculo Liso/efeitos dos fármacos , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Peptídeos Opioides , Receptores Opioides/efeitos dos fármacos
17.
Br J Pharmacol ; 120(6): 989-94, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9134207

RESUMO

1. The density and affinity of binding sites for the delta-selective opioid ligands [3H]-[D-Ala2, Asp4]deltorphin (DELT-I), [3H]-[D-Ala2Glu4]-deltorphin (DELT-II), [3H]-[D-Pen2,D-Pen5]enkephalin (DPDPE), and [3H]-naltrindole (NTI) were determined in whole brain from 10, 15, 25 and 60 day-old C57BL mice. 2. At all ages, the analyses of the homologous displacement curves, gave best fits to single rather than to multiple site models. The binding capacity (Bmax) labelled by [3H]-NTI was about one half that labelled by [3H]-DELT-I, [3H]-DELT-II and [3H]-DPDPE. In 25 and 60 day-old mouse brain the DPDPE Bmax was 25% less than the deltorphin-II Bmax. 3. In saturation experiments, specific binding of [3H]-DELT-I on adult mouse brain homogenates was best fitted by a two-site model (34%, high affinity site, Kd = 1.08 nM and 66% low affinity sites, Kd = 39.9 nM). 4. DPDPE produced a biphasic inhibition of specific [3H]-DELTI-I binding, from 15 days of age onwards. The relative percentage of high and low affinity sites was 72% and 28% in 15 day-, 65% and 35% in 25 day- and 30% and 70% in 60 day-old mice. 5. In adult mouse brain labelled with [3H]-DELT-I, DELT-II recognized 71% of high-affinity and 29% of low-affinity sites DELT-I and DPDPE produced monophasic inhibition of specific [3H]-DELT-II binding to brain homogenates of adult mice. 6. These data suggest that a sub-population of delta-sites (probably the delta 2-subtype), recognized by DELT-I, with high affinity for DELT-II and low affinity for DPDPE develops from 25 days onward. 7. In electrically stimulated mouse vas deferens (MVD) the rank order of potency of the three delta-agonists was: DELT-I > DELT-II > DPDPE in 10 day-old mice: and DELT-I- DELT-II > DPDPE, from 25 days onward. During this time, the potency of DELT-II increased about 15 fold whereas the potency of DELT-I and DPDPE increased only 5 times. The higher efficacy of DELT-II could depend on receptor maturation towards the delta 2-subtype.


Assuntos
Encéfalo/crescimento & desenvolvimento , Receptores Opioides delta/metabolismo , Ducto Deferente/crescimento & desenvolvimento , Animais , Animais Lactentes , Encéfalo/metabolismo , Estimulação Elétrica , D-Penicilina (2,5)-Encefalina , Encefalinas/metabolismo , Feminino , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oligopeptídeos/metabolismo , Ducto Deferente/efeitos dos fármacos
18.
Br J Pharmacol ; 132(7): 1485-92, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11264242

RESUMO

1. Mice lacking the mu-opioid receptor have been recently generated. Centrally mediated responses of mu-opioid agonists are suppressed whereas some of the delta-opioid responses are preserved in these mutant mice. 2. The vas deferens bioassay has been used in this study to investigate the functional activity at a peripheral level of mu- and delta-opioid agonists in mice lacking mu-opioid receptors. 3. The different mu-opioid agonists evaluated, morphine, DAMGO, dermorphin and [Lys(7)]-dermorphin produced an inhibitory response in vas deferens from wild-type mice but had no relevant activity on vas deferens from mutant mice. 4. The selective delta-opioid agonists DPDPE, BUBU, deltorphin I, deltorphin II and [D-Met(2)]-deltorphin induced inhibitory effects in vas deferens from both wild-type and mutant mice. However, the biological activities of these ligands were slightly reduced in preparations from mutant mice. The inhibitory responses of all these delta-opioid agonists were prevented by the administration of the selective delta-opioid antagonist naltrindole. 5. These data indicate that delta-opioid agonists, but not mu-opioid agonists, are biologically active in vas deferens from mice lacking mu-opioid receptors. The decreased response of delta-agonists in mutant mice suggests that some cooperativity may exist between mu- and delta-opioid receptors in these vas deferens preparations.


Assuntos
Naltrexona/análogos & derivados , Receptores Opioides delta/agonistas , Receptores Opioides mu/agonistas , Ducto Deferente/efeitos dos fármacos , Analgésicos Opioides/farmacologia , Animais , Relação Dose-Resposta a Droga , Estimulação Elétrica , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , D-Penicilina (2,5)-Encefalina/farmacologia , Feminino , Genótipo , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Mutantes , Morfina/farmacologia , Contração Muscular/efeitos dos fármacos , Naltrexona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Oligopeptídeos/farmacologia , Receptores Opioides delta/antagonistas & inibidores , Receptores Opioides mu/deficiência , Receptores Opioides mu/genética , Ducto Deferente/fisiologia
19.
Int J Parasitol ; 30(11): 1181-5, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11027785

RESUMO

A fragment of the beta-tubulin gene was polymerase chain reaction (PCR) amplified from genomic DNAs of Babesia bovis, Babesia bigemina, Babesia divergens, Babesia major, Babesia caballi, Babesia equi, Babesia microti, Theileria annulata and Theileria sergenti. Single amplification products were obtained for each of these species, but the size of the amplicons varied from 310 to 460 bp. Sequence analysis revealed that this variation is due to the presence of a single intron, which ranged from 20 to 170 bp. The extensive genetic variability at the beta-tubulin locus has been exploited to develop two types of species identification assays. The first assay can be used on samples containing mostly parasite DNA, like those prepared from infected erythrocytes. Following PCR amplification, the species identification is obtained directly from the size of the products (for Babesia species infecting human or horse) or using a simple PCR-restriction fragment length polymorphism (RFLP) protocol (for Babesia species infecting cattle). The second assay can be used on samples prepared from whole blood, that contain both parasite and host DNAs. In this case, due to the strong conservation of the beta-tubulin gene, co-amplification of a gene fragment from the host DNA was observed. A nested PCR assay was developed for the specific amplification of parasite DNA, using a primer designed to span the exon-intron boundary. Direct identification of Babesia species infecting human and horse is again obtained after the electrophoretic separation of the amplification products, while for Babesia and Theileria species infecting cattle, differentiation is based on a nested PCR-RFLP protocol. These methods may be used for the simultaneous identification of horses and cattle carrying multiple parasites by means of a single PCR or using the PCR-RFLP protocol.


Assuntos
Babesia/isolamento & purificação , Babesiose/diagnóstico , Variação Genética/genética , Theileria/isolamento & purificação , Theileriose/diagnóstico , Tubulina (Proteína)/genética , Animais , Babesia/química , Babesia/genética , Babesiose/sangue , Sequência de Bases , Biomarcadores , Bovinos , Primers do DNA/química , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Desoxirribonucleases de Sítio Específico do Tipo II/química , Eletroforese em Gel de Ágar , Cavalos , Humanos , Íntrons , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Sensibilidade e Especificidade , Análise de Sequência de DNA , Theileria/química , Theileria/genética , Theileriose/sangue , Tubulina (Proteína)/química
20.
Chest ; 113(4): 964-7, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9554632

RESUMO

STUDY OBJECTIVE: Inhaled corticosteroid (ICS) treatment is first-line maintenance therapy in bronchial asthma. However, it is not clear whether and when ICS treatment can be withdrawn. The aim of this open study was to assess whether normalization of bronchial responsiveness could be used as a reliable index to assess the opportunity of ICS treatment withdrawal. DESIGN: Open study at two different points in time. SETTING: Outpatient pulmonary clinic. PATIENTS: Eighteen asthmatic subjects. MEASUREMENTS AND RESULTS: ICS therapy was withdrawn in subjects treated with beclomethasone dipropionate, at the maintenance dose of 889+/-246 microg/d for >3 months. Upon recruitment, all subjects were asymptomatic, had FEV1 >70% of predicted value, and were in treatment with beta2-agonists on an as-needed basis. Eight subjects (group 1) had normal bronchial responsiveness (methacholine provocative dose causing a 20% fall in FEV1 [PD20] >2,000 microg) and 10 subjects (group 2) had bronchial hyperresponsiveness (BHR) (PD20 < or = 2,000 microg). After withdrawal of ICS treatment, subjects were followed up for 3 weeks and were asked to record their asthma symptoms (cough, dyspnea, and wheezing) and their beta2-agonist use. At recruitment and at the end of follow-up, subjects underwent spirometry and a methacholine challenge test. Frequency of asthma exacerbation was similar in subjects with normal bronchial responsiveness (NBR) and in subjects with BHR (50% vs 60%), but subjects with NBR tended to remain asymptomatic for longer than those with BHR (mean+/-SD, 10.7+/-4.4 days vs 5.5+/-3.8 days) (p=0.08). None of the subjects reported any condition that could have triggered exacerbation. Asthma exacerbation was associated with a significant decrease in FEV1 (-105+/-107 mL; p<0.05) and in PD20 (-1,332+/-1,020 microg; p<0.001). CONCLUSIONS: Our study shows that the likelihood of asthma exacerbation is not reduced if ICS treatment is withdrawn when the subjects have NBR, but the exacerbation could be delayed. Further studies in larger populations of asthmatics are needed to confirm these findings.


Assuntos
Anti-Inflamatórios/uso terapêutico , Asma/tratamento farmacológico , Asma/fisiopatologia , Beclometasona/uso terapêutico , Hiper-Reatividade Brônquica , Glucocorticoides/uso terapêutico , Adolescente , Adulto , Testes de Provocação Brônquica , Criança , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
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