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1.
Cryo Letters ; 45(2): 106-113, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38557989

RESUMO

BACKGROUND: Cold hardiness of insects from extremely cold regions is based on a principle of natural cryoprotection, which is associated with physiological mechanisms provided by cryoprotectants. OBJECTIVE: Since arctic cold-hardy insects are producers of highly effective cryoprotectants, in this study, the hemolymph of Aporia crataegi L. and Upis ceramboides L. from an extremely cold area (Yakutia) was tested as a secondary component of cryoprotective agents (CPA) for cryopreservation (-80 degree C) of human peripheral blood lymphocytes and skin fibroblasts. MATERIALS AND METHODS: Lymphocytes and skin fibroblasts were treated with various combinations of DMSO and hemolymph extract and step-wise cooled to -80 degree C. Post-cryopreservation cell viability was assessed by vital staining and morphological appearance. RESULTS: Viability was higher when cells were frozen with a mixture containing DMSO and Upis ceramboides hemolymph compared to the cells frozen in DMSO, while cells frozen with DMSO and Aporia crataegi hemolymph did not survive. The fact that hemolymph of not every cold-resistant insect can be used as a secondary agent along with DMSO indicates that only a unique combination of hemolymph components and its compatibility with cells might result in a positive effect. CONCLUSION: Although the use of insect hemolymph as a complementary agent in applied cryopreservation is a problem in terms of practical application, such studies could initiate new trends in the search for the most successful hemolymph-like cryoprotectant systems. https://doi.org/10.54680/fr24210110712.


Assuntos
Borboletas , Besouros , Animais , Humanos , Criopreservação , Dimetil Sulfóxido/farmacologia , Hemolinfa/fisiologia , Crioprotetores/farmacologia , Sobrevivência Celular
2.
Cryobiology ; 73(2): 221-5, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27424094

RESUMO

Yakutia is a part of eastern Siberia, located in north-eastern Russia. The climate of this area is very harsh even by Siberian standards, and is characterized by the absolute temperature minimum, which is below -64.4 °C, and a long period of low temperatures reaching to a range between -47 and -55 °C. Despite such a severe climate, the fauna and flora of Yakutia present a considerably rich biodiversity, suggesting a high adaptation potential of the organisms in this area. In this study, 30 local species of insects belonging to Coleoptera, Diptera and Lepidoptera were selected to investigate cold adaptation. The identification of the cold adaptation strategy was based on the measurement of the insect body supercooling point (SCP) and hemolymph ice-nucleating activity. According to the data collected, there is a high incidence of freeze tolerant species among the insects found in Yakutsk area (Yakutsk, 62° latitude, 130° longitude): 93.3% of them were freeze tolerant, and only 6.7% were freeze avoiding. It is suggested that the evolution of cold hardiness in this region preferably develops for the selection of the strong freeze tolerance that allow the insects to survive extreme cold conditions.


Assuntos
Aclimatação/fisiologia , Temperatura Baixa , Insetos/fisiologia , Animais , Congelamento , Federação Russa
3.
Pharmazie ; 68(12): 926-32, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24400437

RESUMO

Liguzinediol (LZDO) could mediate the positive inotropic effects through sarcoplasmic reticulum Ca2+ ATPase-dependent mechanism without the risk of arrhythmia. However, the pharmacophore of LZDO contributed to the activities was not clear. The aim of this work was to explore the relationship between positive inotropic effect and scaffold of LZDO as well as to check whether the pharmacophore of LZDO on anti-heart failure activity was located at the pyrazine ring. A series of LZDO analogs (3a-b, 4a-b, 9-19) were designed and synthesised, and their activities were evaluated on isolated heart contractility by Langendorff perfusion. The results showed that the efficacy of LZDO was reduced when the hydroxyl, carboxyl or ester moieties at the side chain position of LZDO were induced, and the para-dihydroxy in LZDO was necessary for its activity. Thus, the pharmacophore of the positive inotropic effect might be located at the whole scaffold of LZDO, but not at the pyrazine ring. The finding may provide an important clue of the pharmacophore for the development of novel cardiotonic agents.


Assuntos
Cardiotônicos/síntese química , Cardiotônicos/farmacologia , Pirazinas/síntese química , Pirazinas/farmacologia , Animais , Ésteres/síntese química , Coração/efeitos dos fármacos , Hidroxilação , Técnicas In Vitro , Indicadores e Reagentes , Masculino , Contração Miocárdica/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
4.
Cryo Letters ; 33(2): 135-43, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22576117

RESUMO

Insects in Siberia must tolerate some of the coldest conditions on earth. The relationship between hemolymph ice nucleating activity, glycerol and total protein concentrations, and cold hardiness was explored in Aporia crataegi L. (Lepidoptera: Pieridae). Cold-hardened overwintering caterpillars were collected at a time of year when temperatures are regularly below -50 degree C, and warm-acclimated at +22 degree C, to see how changes in the physical and chemical properties of the hemolymph influence their cold hardiness potential. Warm acclimation led to a decrease in glycerol and proteins content in the hemolymph, which was associated with the decrease in ice nucleating activity and dramatic loss of cold hardiness potential of the caterpillars. It is suggested that one of the effects of cryoprotection in the freeze tolerant insects, caused by glycerol, might be associated with its ability to form larger aggregates of ice nucleating polypeptides that initiate the ice nucleation at high subzero temperatures. Such ice nucleating structures seem to ensure a high probability of ice nucleation at relatively high temperatures, which may contribute to the extraordinary cold hardiness of A. crataegi caterpillars, which may tolerate temperatures below -85 degree С.


Assuntos
Glicerol/metabolismo , Hemolinfa/metabolismo , Gelo/análise , Proteínas de Insetos/metabolismo , Lepidópteros/metabolismo , Aclimatação , Animais , Temperatura Baixa , Glicerol/sangue , Proteínas de Insetos/sangue , Estações do Ano , Sibéria
5.
Curr Med Chem ; 19(18): 2924-56, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22519396

RESUMO

Rheumatoid arthritis (RA) is a chronic, inflammatory disease that afflicts 1-2% of the world population, characterized by an immune mediated inflammatory synovitis that leads to joint destruction, functional impairment, and reduced quality of life. The treatment goals of RA should be longterm substantial relief of pain, arrested joint inflammation and damage, and improved function. Current treatment can be divided into four classes, namely general analgesics and non-steroidal anti-inflammatory drugs (NSAIDs), glucocorticoids, disease modifying anti-rheumatic drugs (DMARDs) and biological agents (tumor-necrosis factor modifiers). However, gastrointestinal (GI) side effects of NSAIDs cannot be neglected, direct joint injections of glucocorticoids cannot be injected more than once every 3 months, synthetic DMARDs is far from optimal and only minority of patients achieved longterm remission, the biologics are very expensive to manufacture, need to be injected, and can cause allergic reactions. An alternative and good approach to the treatment of this disease is to lower the levels of tumour necrosis factor-α (TNF-α) in RA, which can be achieved by selectively inhibiting the tumour necrosis factor-α converting enzyme (TACE) that generate these cytokines using cheaper small molecules. This review focuses on the current status of selective small molecule inhibitors of TACE, with respect to lead compound search, inhibitors design approach, structure-activity relationship (SAR) and pharmacological studies in animals and humans. Through these methods, new hope is emerging for the treatment of RA through selective inhibition of TACE.


Assuntos
Proteínas ADAM/antagonistas & inibidores , Antirreumáticos/química , Inibidores de Proteases/química , Proteína ADAM17 , Animais , Antirreumáticos/farmacologia , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Desenho de Fármacos , Humanos , Inibidores de Proteases/farmacologia , Inibidores de Proteases/uso terapêutico
6.
Curr Med Chem ; 18(7): 977-1001, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21254976

RESUMO

Osteoarthritis (OA) is the leading cause of joint pain and disability in middle-aged and elderly patients, and is characterized by progressive loss of articular cartilage that eventually leads to a complex process involving degradation of various components of the cartilage matrix, chief among them are the cartilage-specific type II collagen (CII) and aggrecan. While the loss of aggrecan is thought to be an early and reversible process, degradation of CII is considered to be irreversible and a key step in the loss of structural and functional integrity of cartilage. Among the various matrix metalloproteinases (MMPs), MMP-13 is specifically expressed in the cartilage of human OA patients and is not present in normal adult cartilage. It is the major collagenase in OA cartilage and has the highest activity against CII. However, the clinical utility of broad-spectrum MMP inhibitors developed for treatment of OA has been restricted by dose- and duration-dependent musculoskeletal side effects in humans. Consequently, selectively inhibiting the MMP-13 would seem to be an attractive therapeutic objective. This review mainly focuses on selective MMP-13 inhibitors development in terms of OA since the late 90s, in terms of synthetic compounds of low molecular mass incorporating specific zinc-binding groups, non-zinc-binding groups. In addition, dual inhibitors of MMP-13 and aggrecanase are also reviewed. Special emphasis is placed on logistic concerns for lead compound search as well as the structure-activity relationship (SAR) in this field. Through these methods, new hope is emerging for the treatment of OA through selective inhibition of MMP-13.


Assuntos
Inibidores de Metaloproteinases de Matriz , Osteoartrite/tratamento farmacológico , Osteoartrite/enzimologia , Inibidores de Proteases/farmacologia , Cartilagem/enzimologia , Humanos , Metaloproteinase 13 da Matriz/metabolismo , Inibidores de Proteases/síntese química , Inibidores de Proteases/química , Relação Estrutura-Atividade
7.
J Comp Physiol B ; 179(5): 563-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19153749

RESUMO

Larvae of the Siberian timberman beetle Acanthocinus aedilis display a number of unique features, which may have important implications for the field of cold hardiness in general. Their supercooling points are scattered over a wide temperature range, and some individuals have supercooling points in the low range of other longhorn beetles. However, they differ from other longhorn beetles in being tolerant to freezing, and in the frozen state they tolerate cooling to below -37 degrees C. In this respect they also differ from the European timberman beetles, which have moderate supercooling capacity and die if they freeze. The combination of freezing tolerance and low supercooling points is unusual and shows that freezing at a high subzero temperature is not an absolute requirement for freezing tolerance. Like other longhorn beetles, but in contrast to other freeze-tolerant insects, the larvae of the Siberian timberman have a low cuticular water permeability and can thus stay supercooled for long periods without a great water loss. This suggests that a major function of the extracellular ice nucleators of some freeze-tolerant insects may be to prevent intolerable water loss in insects with high cuticular water permeability, rather than to create a protective extracellular freezing as has generally been assumed. The freezing tolerance of the Siberian timberman larvae is likely to be an adaptation to the extreme winter cold of Siberia.


Assuntos
Aclimatação , Besouros/fisiologia , Congelamento , Animais , Frio Extremo , Hibernação/fisiologia , Larva/fisiologia
8.
Izv Akad Nauk Ser Biol ; (4): 459-63, 2008.
Artigo em Russo | MEDLINE | ID: mdl-18771030

RESUMO

A shift in the adaptation strategy depending on the temperature regime within the species range has been revealed in three species of cold-hardy insects inhabiting central Yakutia: Pieris rapae, Acanthocinus aedilis, and Cossus cossus. In warmer climates of northern Europe, these species adopt the strategy of freezing avoidance, whereas in the extremely cold climate of central Yakutia they become freezing-tolerant. This shift probably provides for the ability of these species for unlimited migration and settling in habitats with diverse climatic conditions.


Assuntos
Aclimatação/fisiologia , Insetos/fisiologia , Sensação Térmica , Animais , Temperatura Baixa
9.
J Comp Physiol B ; 178(8): 977-84, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18563418

RESUMO

The strategy for cold-hardiness and water balance features of two closely related families of Coleoptera, Cerambycidae and Chrysomelidae, were investigated. Cerambycids were freeze-avoiding with low supercooling points, whereas chrysomelids froze at high temperatures and were tolerant to freezing. Hence, the two families have adopted different strategies for cold-hardiness. Due to their low trans-cuticular water permeability, the cerambycids have low rates of evaporative water loss. Chrysomelids have much higher trans-cuticular water permeability, but freezing brings their body fluids in vapour pressure equilibrium with ice and prevents evaporative water loss. The differences in cold-hardiness strategies and rates of water loss are likely to reflect the water content of the diets of the two families. Cerambycids feed on dry wood with low water content, causing a restrictive water balance. Chrysomelids feed on leaves with high water content and may use evaporation through the cuticle as a route of water excretion. Haemolymph ice nucleators help chrysomelids to freeze at a high temperature and thus to maximize the period they spend in the water saving frozen state. The diet-related differences in water balance may be the reason why the two families have developed different strategies for cold-hardiness.


Assuntos
Aclimatação , Regulação da Temperatura Corporal , Clima Frio , Temperatura Baixa , Besouros/fisiologia , Equilíbrio Hidroeletrolítico , Animais , Proteínas Anticongelantes/metabolismo , Besouros/metabolismo , Dieta , Congelamento , Proteínas de Insetos/metabolismo , Permeabilidade , Estações do Ano , Especificidade da Espécie , Perda Insensível de Água
10.
Biofizika ; 52(4): 747-52, 2007.
Artigo em Russo | MEDLINE | ID: mdl-17907420

RESUMO

Cold hardiness in 20 insect species living in extremely cold climate of Yakutia has been investigated for the first time. It was shown that the Yakutian insects prefer to use the strategy of freeze tolerance according to which they produce special substances initiating the freezing of hemolymph at high subzero temperatures. The presence of ice-nucleating agents in the haemolymph of insects belonging to the phylogenetic group of Lepidopteran was shown. We postulate that Pieris rapae may shift between the different cold hardiness strategies when they move from moderately cold regions to a more severe environment.


Assuntos
Aclimatação/fisiologia , Hemolinfa/fisiologia , Lepidópteros/fisiologia , Animais , Temperatura Baixa , Sibéria
11.
Izv Akad Nauk Ser Biol ; (5): 596-601, 2006.
Artigo em Russo | MEDLINE | ID: mdl-17086969

RESUMO

Original experimental data describing the strategy for cold adaptation of the winter form of black-veined white Aporia crataegi L. living in Central Yakutia, a region with a harsh continental climate and long and very cold winters, are presented in comparison with other insects of Yakutia. Open wintering insects were shown to develop an efficient water-conservation mechanism in a frozen state. This can be significant for their survival in post-diapause. Certain relationships between water balance, wintering mode, and strategy for cold adaptation have been revealed by the example of several insect species of this region in comparison with insects living in less severe climatic conditions.


Assuntos
Adaptação Fisiológica , Água Corporal/metabolismo , Borboletas/fisiologia , Clima Frio , Animais , Borboletas/metabolismo , Hemolinfa/metabolismo , Estações do Ano , Sibéria
12.
Izv Akad Nauk Ser Biol ; (5): 547-52, 2003.
Artigo em Russo | MEDLINE | ID: mdl-14735784

RESUMO

Glycerol, alpha-carotene, and other yet unidentified compounds have been found in the ethanol extract from winter caterpillars of the black-veined white (Aporia crataegi L.). We have shown that the ethanol extract has a cryoprotective effect on human peripheral blood lymphocytes, and this activity is approximately three times higher than that of glycerol (particularly, in the case of repeated freezing), which is one of the best cryoprotectors.


Assuntos
Borboletas/química , Crioprotetores/farmacologia , Linfócitos/efeitos dos fármacos , Extratos de Tecidos/farmacologia , Animais , Aminas Biogênicas/isolamento & purificação , Aminas Biogênicas/farmacologia , Preservação de Sangue , Carotenoides/isolamento & purificação , Carotenoides/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Crataegus , Criopreservação , Crioprotetores/isolamento & purificação , Etanol/química , Congelamento , Glicerol/isolamento & purificação , Glicerol/farmacologia , Humanos , Linfócitos/fisiologia , Estações do Ano , Extratos de Tecidos/isolamento & purificação
13.
Proc Natl Acad Sci U S A ; 98(26): 15089-94, 2001 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-11752456

RESUMO

Human hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. In this work, we report on a comprehensive characterization of gene expression profiles of hepatitis B virus-positive HCC through the generation of a large set of 5'-read expressed sequence tag (EST) clusters (11,065 in total) from HCC and noncancerous liver samples, which then were applied to a cDNA microarray system containing 12,393 genes/ESTs and to comparison with a public database. The commercial cDNA microarray, which contains 1,176 known genes related to oncogenesis, was used also for profiling gene expression. Integrated data from the above approaches identified 2,253 genes/ESTs as candidates with differential expression. A number of genes related to oncogenesis and hepatic function/differentiation were selected for further semiquantitative reverse transcriptase-PCR analysis in 29 paired HCC/noncancerous liver samples. Many genes involved in cell cycle regulation such as cyclins, cyclin-dependent kinases, and cell cycle negative regulators were deregulated in most patients with HCC. Aberrant expression of the Wnt-beta-catenin pathway and enzymes for DNA replication also could contribute to the pathogenesis of HCC. The alteration of transcription levels was noted in a large number of genes implicated in metabolism, whereas a profile change of others might represent a status of dedifferentiation of the malignant hepatocytes, both considered as potential markers of diagnostic value. Notably, the altered transcriptome profiles in HCC could be correlated to a number of chromosome regions with amplification or loss of heterozygosity, providing one of the underlying causes of the transcription anomaly of HCC.


Assuntos
Carcinoma Hepatocelular/genética , Transformação Celular Neoplásica/genética , Perfilação da Expressão Gênica , Neoplasias Hepáticas/genética , Fígado/metabolismo , Transcrição Gênica , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , DNA Complementar , Etiquetas de Sequências Expressas , Genes Virais , Vírus da Hepatite B/genética , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Dados de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Transdução de Sinais , Fatores de Transcrição/genética
14.
Bioelectromagnetics ; 15(6): 531-8, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7880166

RESUMO

The purpose of this study was to investigate the effects of 2.45 GHz microwave (MW) radiation on dimethylhydrazine (DMH)-induced colon cancer in mice. The subjects were 115 Balb/c mice 4 weeks of age. The animals were divided into group A (control), group B (DMH), group C (DMH+MW), and group D [DMH + 12-O-tetradecanoylphorbol-13- acetate (TPA)]. Radiation (10 mW/cm2) was delivered dorsally with the E field parallel to the mouse's long body axis in an anechoic chamber. Radiations were administered 3 hr daily, 6 days per week, over a period of 5 months. The average SAR was estimated to be 10-12 W/kg. During the course of radiation treatments, DMH was injected once per week. The tumor promoter TPA was administered once per week for 10 weeks, from the third week on, after the initial treatment. The incidence of tumors did not significantly differ between the three test groups (groups B, C, and D; P > 0.25). However, the number of tumors, the size of the tumors, and the incidence of protuberant and infiltrative types in tumor-bearing animals were higher in group D compared to groups B and C (P < 0.05). No difference was found between groups B and C (P > 0.25). The study indicates that 2.45 GHz microwave radiation at 10 mW/cm2 power density did not promote DMH-induced colon cancers in young mice. The study also showed that TPA could accelerate colon tumor production if a tumor was initiated.


Assuntos
Cocarcinogênese , Neoplasias do Colo/induzido quimicamente , Dimetilidrazinas/efeitos adversos , Micro-Ondas , Acetato de Tetradecanoilforbol/efeitos adversos , Pólipos Adenomatosos/induzido quimicamente , Pólipos Adenomatosos/etiologia , Pólipos Adenomatosos/patologia , Animais , Carcinoma/induzido quimicamente , Carcinoma/etiologia , Carcinoma/patologia , Neoplasias do Colo/etiologia , Neoplasias do Colo/patologia , Pólipos do Colo/induzido quimicamente , Pólipos do Colo/etiologia , Pólipos do Colo/patologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Micro-Ondas/efeitos adversos , Neoplasias Induzidas por Radiação/etiologia , Neoplasias Induzidas por Radiação/patologia , Doses de Radiação
15.
Zhonghua Wai Ke Za Zhi ; 27(7): 424-5, 446, 1989 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-2574654

RESUMO

Six cases of interhemispheric subdural empyema are reported. It is a rare disease due to different infections origins. All of them are under 24 years old. The characteristics symptoms of these cases were intracranial infection, increased ICP, cerebral falx syndrome and focal seizure. The specific appearances on the films of angiography and CT scan were discussed. It could be located these lesions exactly. The surgical treatments were continuous drainage though cranial burr hole or excision of abscess. All 6 cases are cured with no recurrence.


Assuntos
Empiema Subdural , Adolescente , Adulto , Criança , Pré-Escolar , Empiema Subdural/classificação , Empiema Subdural/diagnóstico por imagem , Empiema Subdural/cirurgia , Feminino , Humanos , Lactente , Masculino , Tomografia Computadorizada por Raios X
16.
Vopr Med Khim ; 31(1): 47-51, 1985.
Artigo em Russo | MEDLINE | ID: mdl-3157266

RESUMO

Dynamics of accumulation of alcohol- and aldehyde dehydrogenases inhibitors in liver tissue of rats with chronic alcohol intoxication showed that content of the bioinhibitors of protein nature was increased during the animals alcoholization, whereas inhibition of aldehyde dehydrogenase was more distinct as compared with alcohol dehydrogenase. When the nature of aldehyde dehydrogenase inhibitor was studied using the immunoenzyme analysis, the inhibitor proved to be an autoantibody, produced in chronic alcoholization of rats as a result apparently of the enzyme modification. Titre of specific antibodies to "autoantigen" (aldehyde dehydrogenase from liver tissue of alcohol consuming rats) was 12-16-fold higher in liver tissue and blood serum of rats with alcoholism as compared with the corresponding preparations of control animals. An immuno-enzymological mechanism, responsible for an increase of acetaldehyde content in blood developed after ethanol consumption in alcoholism, is discussed.


Assuntos
Alcoolismo/enzimologia , Aldeído Desidrogenase/antagonistas & inibidores , Fígado/enzimologia , Acetaldeído/metabolismo , Álcool Desidrogenase , Oxirredutases do Álcool/antagonistas & inibidores , Oxirredutases do Álcool/sangue , Alcoolismo/sangue , Aldeído Desidrogenase/sangue , Animais , Humanos , Técnicas Imunoenzimáticas , Extratos Hepáticos/farmacologia , Ratos
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