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1.
Aster spathulifolius, Coreopsis drummondii, Chrysanthemum morifolium, Chrysanthemum boreale, Chrysanthemum indicum and Rudbeckia laciniata var. hortensis had 30–70 mg gallic acid equivalents (GAE)/g dw of the total phenolic contents. Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and reducing powers of tested Compositae plant extract appeared to be linear and consistent with total phenolic/flavonoids compound contents in the same manner with DPPH radical scavenging activity. R. laciniata (200 µg/mL) inhibited nitric oxide (NO) production to approximately 92.8% from lipopolysaccharide (LPS)-stimulated macrophage cells. Although the total phenolic/flavonoids contents and antioxidant activity of R. laciniata is low compared with other Compositae plants, R. laciniata shows the superior inhibitory activity against NO biosynthesis from LPS-induced macrophage cells. For antiobesity activity, C. boreale, C. morifolium and C. drummondii might act to accelerate lipid degradation and to decrease lipid synthesis in 3T3-L1 adipocyte cells, and C. indicum, A. spathulifolius and R. laciniata extract had antiobesity activity to inhibit lipid synthesis in 3T3-L1 adipocyte cells.  相似文献   

2.
Lysozymes are widely distributed immune effectors exerting muramidase activity against the peptidoglycan of the bacterial cell wall to trigger cell lysis. However, some invertebrate-type (i-type) lysozymes deficient of muramidase activity still exhibit antimicrobial activity. To date, the mechanism underlying the antimicrobial effect of muramidase-deficient i-type lysozymes remains unclear. Accordingly, this study characterized a novel i-type lysozyme, Splys-i, in the mud crab Scylla paramamosain. Splys-i shared the highest identity with the Litopenaeus vannamei i-type lysozyme (Lvlys-i2, 54% identity) at the amino acid level. Alignment analysis and 3D structure comparison show that Splys-i may be a muramidase-deficient i-type lysozyme because it lacks the two conserved catalytic residues (Glu and Asp) that are necessary for muramidase activity. Splys-i is mainly distributed in the intestine, stomach, gills, hepatopancreas, and hemocytes, and it is upregulated by Vibrio harveyi or Staphylococcus aureus challenge. Recombinant Splys-i protein (rSplys-i) can inhibit the growth of Gram-negative bacteria (V. harveyi, Vibrio alginolyticus, Vibrio parahemolyticus, and Escherichia coli), Gram-positive bacteria (S. aureus, Bacillus subtilis, and Bacillus megaterium), and the fungus Candida albicans to varying degrees. In this study, two binding assays and a bacterial agglutination assay were conducted to elucidate the potential antimicrobial mechanisms of Splys-i. Results demonstrated that rSplys-i could bind to all nine aforementioned microorganisms. It also exhibited a strong binding activity to lipopolysaccharide from E. coli and lipoteichoic acid and peptidoglycan (PGN) from S. aureus but a weak binding activity to PGN from B. subtilis and β-glucan from fungi. Moreover, rSplys-i could agglutinate these nine types of microorganisms in the presence of Ca2+ at different protein concentrations. These results suggest that the binding activity and its triggered agglutinating activity might be two major mechanisms of action to realize the muramidase-deficient antibacterial activity. In addition, rSplys-i can hydrolyze the peptidoglycan of some Gram-positive bacteria because it exhibits weak isopeptidase activities in salt and protein concentration-dependent manner. This result indicates that such an isopeptidase activity may contribute to the muramidase-deficient antimicrobial activity to a certain degree. In conclusion, Splys-i is upregulated by pathogenic bacteria, and it inhibits bacterial growth by binding and agglutination activities as well as isopeptidase activity, suggesting that Splys-i is involved in immune defense against bacteria through several different mechanisms of action.  相似文献   

3.
Experiments were performed to determine whether rats whose spontaneous locomotor activity had been decreased by the placement of bilateral electrolytic lesions in the tuber cinereum of the hypothalamus could be forced to run on a treadmill. All rats with small medial lesions, some rats with large medial lesions, and most rats with lateral lesions needed no more prodding to run on the treadmill than they needed before receiving their lesions. While some rats with large medial lesions and some with lateral lesions usually needed more prodding to keep them running, they, nevertheless, were able to run on the treadmill; in fact, most of these rats occasionally ran as well as did the control rats. Only one rat, a rat with large medial lesions, refused to run. These data suggest that a lack of ability to run cannot explain the hypoactivity observed in these rats.  相似文献   

4.

Introduction

The aim of the study was to examine the cytotoxicity and evaluate the antiviral and virucidal activity of methanol and methanol/H2O extracts from the herb of Peucedanum salinum. Plants belonging to the genus Peucedanum (Apiaceae family) have been used in traditional medicine for a long time.

Material and methods

The examination of the cytotoxicity of the extracts in the concentrations of 0.1, 0.2, 0.5, 1, 2, 4 mg/ml was carried out on the cell culture line HEK-293. Cytotoxicity of the examined extracts was measured by the colorimetric MTT (tetrazolium) method. After determination of the highest non-toxic concentration of examined extracts, antiviral and virucidal activity against adenovirus type 5 (Adenoviridae) was established.

Results

The non-toxic doses were as follows: 1 mg/ml of methanol extract and 2 mg/ml of methanol/H2O extract (1 : 1 v/v). Antiviral activity was observed for the methanol extract of Peucedanum salinum in concentrations of 0.5 and 1 mg/ml. The extract caused the decrease of titre of the virus by 2 log and 1.33 log, respectively. The methanol/H2O extract (1 : 1 v/v) decreased the titre of the virus by 1.33 log and 1.5 log in concentrations of 1 and 2 mg/ml, respectively. The examined extracts had no virucidal activity against adenovirus type 5.

Conclusions

The examined extract is a new, potentially active source of active substances possessing antiviral activity and further studies are needed.  相似文献   

5.
Disturbances of the autonomic nervous system play a crucial role in the pathogenesis and clinical course of many diseases. Recently, rapid development has occurred in the clinical assessment of autonomic function. Various procedures have been described as diagnostic tools to monitor autonomic dysfunction. Some of them are mostly used for research purposes. Many, however, have found their place in routine clinical evaluation. Our paper presents selected methods of assessment of the autonomic nervous system with particular emphasis on those that are useful in diagnosis and treatment of diseases of the cardiovascular system. We discuss multiple tests based on cardiovascular reflexes, methods of studying heart rate variability as well as direct catecholamine measurements. Moreover, we outline tests of sudomotor function and microneurography.  相似文献   

6.
This study investigated (a) possible associations of the large individual variation in startle, with accompanying autonomic, central nervous system, and myogenic activities in a habituation paradigm; and (b) the patterns of habituation of these variables. Startle blinks to 40 noise bursts, heart rate, alpha activity, and orbicularis oculi electromyographic (EMG) activity preceding and following each startle response were measured in 40 normal 7–11-year-old boys. Statle amplitude and its habituation were independent of association with either initial values or successive changes in the autonomic, alpha, and EMG activities; whereas startle habituated, pre-and poststartle myogenic, alpha, and cardiac activities failed to habituate. Tonic cardiac activity was facilitated, suggesting sensitization of state, as proposed in the dual-process theory of habituation.  相似文献   

7.
Infant autonomic reactivity to stress is a potential predictor of later life health complications, but research has not sufficiently examined sympathetic activity, controlled for effects of physical activity and respiration, or studied associations among autonomic adjustments, cardiac activity, and affect in infants. We studied 278 infants during the repeated Still-Face Paradigm, a standardized stressor, while monitoring cardiac activity (ECG) and respiratory pattern (respiratory inductance plethysmography). Video ratings of physical activity and affect were also performed. Respiratory sinus arrhythmia (RSA) and T-wave amplitude (TWA) served as noninvasive indicators of cardiac parasympathetic and sympathetic activity, respectively. Responses were compared between infants who completed two still-face exposures and those who terminated after one exposure due to visible distress. Findings, controlled for physical activity, showed robust reductions in respiration-adjusted RSA and TWA, with more tonic attenuation of TWA. Infants completing only one still-face trial showed more pronounced autonomic changes and less recovery from stress. They also showed elevated minute ventilation, suggesting hyperventilation. Both reductions in adjusted RSA and TWA contributed equally to heart rate changes and were associated with higher negative and lower positive affect. These associations were more robust in the group of distressed infants unable to complete both still-face trials. Thus, cardiac sympathetic activation and parasympathetic withdrawal are part of the infant stress response, beyond associated physical activity and respiration changes. Their association with cardiac chronotropy and affect increases as infants' distress level increases. This excess reactivity to social stress should be examined as a predictor of future cardiovascular disease.  相似文献   

8.
Strain BO-07 was isolated from the root tissue of Boesenbergia rotunda (L.) Mansf A. and identified as Streptomyces sp. on the basis of morphology, chemotaxonomy and 16S rDNA sequencing. The fractionation of the crude extract from strain BO-07 cultures led to the isolation of two biphenyls: 3′-hydroxy-5-methoxy-3,4-methylenedioxybiphenyl (1) and 3′-hydroxy-5,5′-dimethoxy-3,4-methylenedioxybiphenyl (2); these compounds and the crude extract had potent antibacterial activity against Gram-positive bacteria, and antioxidant and anticancer activities. These compounds showed the highest activity against Staphylococcus aureus ATCC25932, Bacillus cereus ATCC7064 and Bacillus subtilis ATCC6633 with a minimum inhibitory concentration value of 0.5?µg/ml and minimum bactericidal concentration of 2–8?µg/ml. Compounds 1 and 2 showed the highest (1, 1diphenyl-2-picryl hydrazyl) DPPH antioxidant activity with a scavenging concentration (SC50) value of 85.84 and 88.26?µg/ml, respectively, and also showed strong cytotoxicity against all the three cancer cell lines (HeLa, HepG2 and Huh7) at an IC50 value of 3.04–20.30?μg/ml. Both the compounds were less toxic on normal cells (L929) than on the investigated cancer cell lines.  相似文献   

9.
Extracts from five indigenous Palestinian medicinal plants including Rosmarinus officinalis, Pisidium guajava, Punica granatum peel, grape seeds and Teucrium polium were investigated for antimicrobial and free radical scavenging activities against eight microorganisms, using well diffusion method. The microorganisms included six bacterial isolates (i.e. Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginos, Klebsiella pneumonia, Bacillus subtilis and Micrococcus luteus) and two fungal isolates (i.e. Candida albicans and Aspergillus niger). A standard antioxidant assay was performed on the plant extracts to assess their capability in scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH). Of the five tested plant extract, only Rosmarinus offcinalis extract contained significant antimicrobial activity against all eight microbial isolates including Pseudomonas aeruginosa. Extracts from other four plants exhibited a variable antimicrobial activity against all microorganisms, except Pseudomonas aeruginosa. Significant antioxidant activity was detected in all plant extracts. However, extracts from Pisidium guajava leaves contained significantly higher antioxidant activity compared to the other extracts tested. The antimicrobial and scavenging activities detected in this in vitro study in extracts from the five Palestinian medicinal plants suggest that further study is needed to identify active compounds to target diseases caused by a wide-spectrum pathogens.  相似文献   

10.
Running-wheel activity for 24 hr and activity patterns were studied during chronic theophylline administration. Theophylline altered the normal relations between activity level and illumination. Dark-time activity was decreased to approximately 50% and 24 hr activity was unaffected. These observations were consistent with previous results showing that theophylline suppressed dark-time feeding but had no effect on 24 hr food intake. A possible mechanism to account for these results may be dependent on levels and turnover of brain norepinephrine.  相似文献   

11.

Background

Methanol extracts and alkaloid fractions of different parts of four plant species belonging to Solanaceae family and used in Mexican traditional medicine were investigated for their total phenolic contents, anti-inflammatory and antioxidant properties.

Materials and Methods

The total phenolic compounds of each extract was determined according to the Folin-Ciocalteu method, while the in vitro radical scavenging activities of the extracts were assessed using the DPPH and ABTS radicals. The in vivo anti-inflammatory activity was determined using the TPA-induced mouse ear edema model.

Results

The methanol extracts contained the highest concentrations of phenolic compounds and also exhibited the best reducing power on the DPPH and ABTS radicals, in a concentration-dependent fashion. However, the anti-inflammatory activity did not follow the same trend, as some alkaloid fractions that showed low radical reducing power exhibited the strongest anti-inflammatory activity.

Conclusion

The methanol extract obtained from the flowers of Nicotiana glauca presented the best overall performance with the largest amount of phenolic compounds (111 µg garlic acid equivalents/g of extract), the best antioxidant activity (94.80% inhibition of DPPH and 97.57% of ABTS) and the highest anti-inflammatory activity (81.93% inhibition of the inflammation).  相似文献   

12.
13.
14.
BackgroundCervical cancer is common in women in less developed regions of the world. The plant biomolecules can be employed for synergistic activity with chemo- and radiotherapy. This combinations might result in reduced toxicity and increased efficacy of the treatment regimen.ObjectivesThe anti-HeLa cells activity of the acetone extracts of S. plumosum, T. cilliata and S. pinnata was assessed using different parameters.MethodsSecondary metabolite detection and antioxidant activity quantification were determined using the DPPH and ferric iron reducing assays. HeLa cell growth inhibition and mechanistics were assessed by employing MTT and Annexin-V flous assays.ResultsObservations revealed the presence of phenolic, flavonoids, tannins steroids and coumarins in all the plants extracts. High amount of total phenolic and flavonoid content were detected in S. plumosum and T. cilliata. S. plumosum extract had the best DPPH scavenging activity and ferric reducing powers.ConclusionObservable concentration dependent cell proliferation inhibition by test materials was exhibited. The leaf extracts from T. cilliata, S. plumosum and S. pinnata contain compounds of various polarities with free-radical, antioxidant and anti-cancerous activities that may play a beneficial role in treatment.  相似文献   

15.
利用BEAM分析技术,以50例正常人为对照,用Z值概率差异地形图,对83例部分性与全面性发作的癫痫病人脑电背景活动的δ与θ不对称性情况进行分析,并与其它结果比较后显示,BEAM对癫痫病人的不对称性δ、θ的检出率达72%,较EEG目测分析敏感,其显示的病变区与EEG目测分析、CT、SPECT结果大多符合,可用作痫灶的定侧定位,亦有助于全面性癫痫与部分性癫痫的鉴别。  相似文献   

16.
17.
In crustaceans, Kazal-type serine proteinase inhibitors in hemolymph are believed to function as regulators of the host-defense reactions or inhibitors against proteinases from microorganisms. In this study, we report a Kazal-type serine proteinase inhibitor, named hcPcSPI1, from freshwater crayfish (Procambarus clarkii). We found that hcPcSPI1 is composed of a putative signal peptide, an RGD motif, and three tandem Kazal-type domains with the domain P1 residues L, L and E, respectively. Mainly, hcPcSPI1 was detected in hemocytes as well as in the heart, gills, and intestine at both the mRNA and protein levels. Quantitative real-time PCR analysis showed that hcPcSPI1 in hemocytes was upregulated by the stimulation of Esherichia coli (8099) or became decreased after a white spot syndrome virus (WSSV) challenge. In addition, hcPcSPI1 and its three independent domains were overexpressed and purified to explore their potential functions. All four proteins inhibited subtilisin A and proteinase K, but not α-chymotypsin or trypsin. Recombinant hcPcSPI1 could firmly attach to Gram-negative bacteria E. coli and Klebsiella pneumoniae; Gram-positive bacteria Bacillus subtilis, Bacillus thuringiensis and Staphylococcus aureus; fungi Candida albicans and Saccharomyce cerevisiae, and only domain 1 was responsible for the binding to E. coli and S. aureus. In addition, recombinant hcPcSPI1 was also found to possess bacteriostatic activity against the B. subtilis and B. thuringiensis. Domains 2 and 3 contributed mainly to these bacteriostatic activities. All results suggested that hcPcSPI1 might play important roles in the innate immunity of crayfish.  相似文献   

18.
I. M. Sechenov First Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR T. T. Berezov.) Translated from Byuelleten' Éksperimental'noi Biologii i Meditsiny, Vol. 106, No. 7, pp. 99–101, July, 1988.  相似文献   

19.
Cardio-respiratory coupling is reciprocal; it is expressed as respiratory-modulated sympathetic nerve activity and pulse-modulated respiratory motor activity. In the brainstem, the neuraxis controlling cardio-respiratory functions forms a ventrolateral cell column which extends to the dorsolateral (dl) pons. Our general working hypothesis is that these control systems converge at points with the common purpose of gas exchange and that neural activity along this axis coordinates both arterial pulse pressure and breathing. Here, we review the data showing that pontine nuclei modulate heart rate, blood pressure and breathing, and present new results demonstrating a vagal influence on pontine activity modulated with both arterial pulse pressure and phrenic nerve activity in the decerebrate cat. Generally with the vagi intact, dl pontine activity was weakly modulated by both arterial pulse pressure and respiratory pattern. After bilateral vagotomy, the strength and consistency of respiratory modulation increased significantly, although the strength and consistency of arterial pulse pressure modulation did not change significantly for the group; a decrease in some (62%) was offset by an increase in others (36%) neurons. Thus, the vagus shapes the envelope of the cycle-triggered averages of neural activity for both the respiratory and cardiac cycles. These data provide insight into the neural substrate for the prominent vagal effect on the cardio-respiratory coupling pattern, in particular respiratory sinus arrhythmia. While these results support convergence of inputs to neural populations controlling breathing and cardiovascular functions, the physiologic role of balancing ventilation, vascular resistance, heart rate and blood flow for the benefit of tissue oxygenation, remains hypothetical.  相似文献   

20.
Research Institute of Physicochemical Medicine, Ministry of Health of the RSFSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR Yu. M. Lopukhin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol, 110, No. 7, pp. 48–50, July, 1990.  相似文献   

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