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1.
BackgroundInadequate representation of the human tissue environment during a preclinical screen can result in inaccurate predictions of compound effects. Consequently, pharmaceutical investigators are searching for preclinical models that closely resemble original tissue for predicting clinical outcomes.MethodsThe current research aims to compare the impact of using serum-free medium instead of complete culture medium during the last step of psoriatic skin substitute reconstruction. Skin substitutes were produced according to the self-assembly approach.ResultsSerum-free conditions have no negative impact on the reconstruction of healthy or psoriatic skin substitutes presented in this study regarding their macroscopic or histological appearances. ATR-FTIR results showed no significant differences in the CH2 bands between psoriatic substitutes cultured with or without serum, thus suggesting that serum deprivation did not have a negative impact on the lipid organization of their stratum corneum. Serum deprivation could even lead to a better organization of healthy skin substitute lipids. Percutaneous analyses demonstrated that psoriatic substitutes cultured in serum-free conditions showed a higher permeability to hydrocortisone compared to controls, while no significant differences in benzoic acid and caffeine penetration profiles were observed.ConclusionsResults obtained with this 3D-psoriatic skin substitute demonstrate the potential and versatility of the model. It could offer good prediction of drug related toxicities at preclinical stages performed in order to avoid unexpected and costly findings in the clinic.General significanceTogether, these findings offer a new approach for one of the most important challenges of the 21st century, namely, prediction of drug toxicity.  相似文献   

2.
Abstract

In standard histological technique, aromatic solvents such as xylene and toluene are used as clearing agents between ethanol dehydration and paraffin embedding. In addition, these solvents are used for de-waxing paraffin sections. Unfortunately, these solvents are harmful and therefore adequate substitutes would be useful. We suggest the use of n-heptane as a convenient substitute for xylene. Paraffin sections of rat tissues processed with n-heptane and stained with hematoxylin-eosin or Masson's trichrome showed proper embedment, well preserved morphology and excellent staining.  相似文献   

3.
《Free radical research》2013,47(6):653-661
Abstract

Nitric oxide (NO) plays a key role in regulation of vascular tone and blood flow. In the microcirculation blood flow is strongly dependent on red blood cells (RBC) deformability. In vitro NO increases RBC deformability. This study hypothesized that NO increases RBC velocity in vivo not only by regulating vascular tone, but also by modifying RBC deformability. The effects of NO on RBC velocity were analysed by intra-vital microscopy in the microcirculation of the chorioallantoic membrane (CAM) of the avian embryo at day 7 post-fertilization, when all vessels lack smooth muscle cells and vascular tone is not affected by NO. It was found that inhibition of enzymatic NO synthesis and NO scavenging decreased intracellular NO levels and avian RBC deformability in vitro. Injection of a NO synthase-inhibitor or a NO scavenger into the microcirculation of the CAM decreased capillary RBC velocity and deformation, while the diameter of the vessels remained constant. The results indicate that scavenging of NO and inhibition of NO synthesis decrease RBC velocity not only by regulating vascular tone but also by decreasing RBC deformability.  相似文献   

4.
Context: Nickel oxide (NiO) nanoparticles (NPs) with appropriate surface chemistry have been widely used for their potential new applications in biomedical industry. Increased usage of these NPs enhances the chance of exposure of personnel involved in the work place.

Objective: This study was designed to assess the ability of NiO NPs to cause biochemical alterations post-acute oral exposure in female Wistar rats.

Materials and methods: Rats were administered with 125, 250, and 500?mg/kg doses of NiO NPs for haematological, biochemical, and histopathological studies. Biodistribution patterns of NiO NPs in female Wistar rats were also monitored.

Results: NiO NPs caused significant (p?Conclusions: This study revealed that exposure to nanosized NiO particles at acute doses may cause adverse changes in animal biochemical profiles. Further, the in vivo studies on toxicity evaluation help in biomonitoring of the potential contaminants.  相似文献   

5.
ABSTRACT

We investigated the effects of quercetin (Q) on some hematological parameters and determined the percentage of alpha-naphthyl acetate esterase (ANAE) positive lymphocytes in rats that had been exposed to cadmium (Cd). Thirty male Wistar albino rats were divided into four groups: control (C), quercetin (Q), cadmium (Cd) and Q + Cd (CdQ). Blood samples were taken to assess erythrocytes (RBC), leukocytes (WBC), hemoglobin levels (Hb), hematocrit values (Hct), platelets (PLT), alpha-naphthyl acetate esterase (ANAE) positive lymphocytes. RBC, Hb, Hct; the number of PLT significantly decreased in the Cd group. To the contrary, these parameters were increased significantly in the CdQ group compared to the Cd group. Although we found a significant increase in total WBC count and neutrophil percentage, the number of lymphocytes decreased in the Cd group compared to the other three groups. Also, the percentage of peripheral blood ANAE positive lymphocytes decreased significantly in the Cd group (p < 0.05). Q exhibits positive effects on some hematological characteristics and the percentage of ANAE positive lymphocyte in cases of acute CD toxicity.  相似文献   

6.
Abstract

Glutathione is an intracellular antioxidant that often becomes depleted in pathologies with high oxidative loads. We investigated the provision of cysteine for glutathione synthesis to the human erythrocyte (red blood cell; RBC). Almost all plasma cysteine exists as cystine, its oxidized form. In vitro, extracellular cystine at 1.0 mM sustained glutathione synthesis in glutathione-depleted RBCs, at a rate of 0.206 ± 0.036 μmol (L RBC)?1min?1 only 20% of the maximum rate obtained with cysteine or N-acetylcysteine. In plasma-free solutions, N-acetylcysteine provides cysteine by intracellular deacetylation but to achieve maximum rates of glutathione synthesis by this process in vivo, plasma N-acetylcysteine concentrations would have to exceed 1.0 mM, which is therapeutically unattainable. 1H-NMR experiments demonstrated that redox exchange reactions between NAC and cystine produce NAC-cysteine, NAC-NAC and cysteine. Calculations using a mathematical model based on these results showed that plasma concentrations of N-acetylcysteine as low as 100 μM, that are attainable therapeutically, could potentially react with plasma cystine to produce ~50 μM cysteine, that is sufficient to produce maximal rates of glutathione synthesis. We conclude that the mechanism of action of therapeutically administered N-acetylcysteine is to reduce plasma cystine to cysteine that then enters the RBC and sustains glutathione synthesis.  相似文献   

7.
Flow analysis at microvascular bifurcation after partial replacement of red blood cell (RBC) with liposome-encapsulated hemoglobin (LEH) was performed using the lattice Boltzmann method. A two-dimensional symmetric Y bifurcation model with a parent vessel diameter of 20 mum and daughter branch diameters of 20 microm was considered, and the distributions of the RBC, LEH, and oxygen fluxes were calculated. When only RBCs flow into the daughter branches with unevenly distributed flows, plasma separation occurred and the RBC flow to the lower-flow branch was disproportionately decreased. On the other hand, when half of RBC are replaced by LEH, the biasing of RBC flow was enhanced whereas LEH flowed favorably into the lower-flow branch, because many LEH within the parent vessel are suspended in the plasma layer, where no RBCs exist. Consequently, the branched oxygen fluxes became nearly proportional to flows. These results indicate that LEH facilitates oxygen supply to branches that are inaccessible to RBCs.  相似文献   

8.
Studies on structure–activity relationships were carried out to characterize the response specificity of the benzoic acid cell of the female of the moth Bombyx mori by means of single sensillum electrophysiological recordings. We demonstrated that this cell type responds best to a natural key substance (benzoic acid) and has similar response profiles for less effective compounds, including various halogen substitutes of benzoic acid, benzaldehyde and other derivates of the key compound. Using different halogen substitutes (F, Cl, Br, I), we showed that the cellular response decreases with increasing atomic size of the substitute and that halogen substitutes were most effective in the meta-position. Thus, m-fluor benzoic acid was even more effective than benzoic acid. These results indicate that a critical feature of the stimulus molecule is the inductive effect generated by the halogen substitutes. Increasing the atomic size of the halogen substitute impairs the recognition of the molecule by the receptor cell, possibly due to steric effects. Decreasing the electron density in the aromatic ring improves the receptor response. The benzoic acid receptor cell can be considered as specialist despite not being involved in pheromone detection as it responds maximally to a key substance and has similar response profiles for less effective compounds.  相似文献   

9.
Three soils with a history of creosote contamination (designated NB, TI and AC) were treated in bench-scale microcosms using conditions (nutrient amendment, moisture content and temperature) which had promoted mineralization of 14C-pyrene in a preliminary study. Bioremediation was monitored using the solid-phase Microtox test, seed germination and earthworm survival assays, SOS-chromotest, Toxi-chromotest and a red blood cell (RBC) haemolysis assay. Contaminant concentrations in the AC soil did not change after 150 days. Polycyclic aromatic hydrocarbon (PAH) concentrations decreased in the NB soil, and toxicity decreased overall according to the earthworm, seed germination and Microtox tests. Although total petroleum hydrocarbons (TPHs) in the TI soil were reduced following treatment, results of the earthworm, seed germination, RBC and Microtox tests suggested an initial increase in toxicity indicating that toxic intermediary metabolites may have formed during biodegradation. Toxicity testing results did not always correlate with contaminant concentrations, nor were the trends indicated by each test consistent for any one soil. Each test demonstrated a different capacity to detect reductions in soil contamination. Journal of Industrial Microbiology & Biotechnology (2000) 24, 132–139. Received 14 June 1999/ Accepted in revised form 12 November 1999  相似文献   

10.
Introduction: Red blood cells (RBC) are the most abundant host cells in the human body. Mature erythrocytes are devoid of nuclei and organelles and have always been regarded as circulating ‘bags of hemoglobin’. The advent of proteomics has challenged this assumption, revealing unanticipated complexity and novel roles for RBCs not just in gas transport, but also in systemic metabolic homeostasis in health and disease.

Areas covered: In this review we will summarize the main advancements in the field of discovery mode and redox/quantitative proteomics with respect to RBC biology. We thus focus on translational/clinical applications, such as transfusion medicine, hematology (e.g. hemoglobinopathies) and personalized medicine. Synergy of omics technologies – especially proteomics and metabolomics – are highlighted as a hallmark of clinical metabolomics applications for the foreseeable future.

Expert commentary: The introduction of advanced proteomics technologies, especially quantitative and redox proteomics, and the integration of proteomics data with omics information gathered through orthogonal technologies (especially metabolomics) promise to revolutionize many biomedical areas, from hematology and transfusion medicine to personalized medicine and clinical biochemistry.  相似文献   


11.
A S Rudolph 《Cryobiology》1988,25(4):277-284
In this report, the ability of carbohydrates (trehalose, sucrose, and glucose) to preserve the blood substitute liposome-encapsulated hemoglobin (LEH) in the freeze-dried state is examined. The water-free stabilization of individual components of this blood substitute and LEH is reported. Lyophilization of hemoglobin solutions in the absence of carbohydrates results in significant oxidative degradation of Hb as measured by a large increase (approximately 60%) in methemoglobin. Hb samples lyophilized in increasing carbohydrate concentrations show reduced levels of methemoglobin, and at 0.5 M trehalose, sucrose, or glucose, these levels are reduced to nearly the same levels as unlyophilized controls. Storage of lyophilized Hb samples following rehydration at 4 degrees C shows the same rate of methemoglobin formation regardless of whether carbohydrates are present. This suggests that carbohydrates prevent Hb oxidation in the dry state but are less effective at retarding oxidative damage to Hb in solution. The addition of 0.25 M trehalose or sucrose to LEH results in the maintenance of liposomal size following lyophilization. In these experiments, glucose was least effective at inhibiting dehydration-induced LEH fusion. Lyophilization of LEH in 0.25 M trehalose or sucrose also results in significantly greater retention of the encapsulated hemoglobin following lyophilization and rehydration. These results suggest that the long-term stabilization of LEH in the dry state is a realizable goal.  相似文献   

12.
 为探索一条研制猪血红蛋白 (pHb)为基础的血液代用品新途径 ,开发了干膜超声法将猪血红蛋白和别构效应剂、超氧化物歧化酶等联合包埋于脂质体的技术 .考察了氢化大豆卵磷脂、二肉豆蔻酰磷脂酰胆碱、胆固醇、二硬脂酰磷脂酰乙醇胺 甲氧基聚乙二醇和维生素E等在制备脂质体包埋血红蛋白 (LEH)中的作用 .通过控制磷脂与其他成分的配比 ,制得包埋率为 10 3%,pHb浓度达 16 %的稳定的LEH ;进一步将pHb微囊通过小鼠尾静脉多次注入其体内 ,检测受试小鼠血液中红细胞和白细胞数、抗体滴度、血小板聚集率及肾脏组织学等方面的变化 .小鼠体内试验表明了所制备的LEH具有低免疫原性、对肾脏无明显损害等特点 .脂质体包埋pHb是一种极具开发前景的稳定的人工载氧系统  相似文献   

13.
Introduction

Bitter melon (Momordica charantia, Cucurbitaceae) is a popular edible medicinal plant, which has been used as a botanical dietary supplement for the treatment of diabetes and obesity in Chinese folk medicine. Previously, our team has proved that cucurbitanes triterpenoid were involved in bitter melon’s anti-diabetic effects as well as on increasing energy expenditure. The triterpenoids composition can however be influenced by changes of varieties or habitats.

Objectives

To clarify the significance of bioactive metabolites diversity among different bitter melons and to provide a guideline for selection of bitter melon varieties, an exploratory study was carried out using a UHPLC-HRMS based metabolomic study to identify chemotypes.

Methods

Metabolites of 55 seed samples of bitter melon collected in different parts of China were profiled by UHPLC-HRMS. The profiling data were analysed with multivariate (MVA) statistical methods. Principle component analysis (PCA) and hierarchical cluster analysis (HCA) were applied for sample differentiation. Marker compounds were identified by comparing spectroscopic data with isolated compounds, and additional triterpenes were putatively identified by propagating annotations through a molecular network (MN) generated from UHPLC-HRMS & MS/MS metabolite profiling.

Results

PCA and HCA provided a good discrimination between bitter melon samples from various origins in China. This study revealed for the first time the existence of two chemotypes of bitter melon. Marker compounds of those two chemotypes were identified at different MSI levels. The combined results of MN and MVA demonstrated that the two chemotypes mainly differ in their richness in cucurbitane versus oleanane triterpenoid glycosides (CTGs vs. OTGs).

Conclusion

Our finding revealed a clear chemotype distribution of bioactive components across bitter melon varieties. While bioactivities of individual CTGs and OTGs still need to be investigated in more depth, our results could help in future the selection of bitter melon varieties with optimised metabolites profile for an improved management of diabetes with this popular edible Chinese folk medicine.

  相似文献   

14.

Smoking is a significant risk factor in fatal pathologies including cardio-cerebrovascular and respiratory diseases. Aluminum (Al) is a toxic element without known biological function, but with recognized toxic effects. Manganese (Mn) and selenium (Se) are essential trace elements involved in cellular antioxidant defense mechanisms. Al, Mn, and Se carry out their metabolic activities via blood flow and tissue oxygenation. The structure and number of red blood cells (RBC) play important role in tissue oxygenation throughout blood flow. Increased hematocrit (Hct) as a result of probable hypoxia induces disturbed blood flow, RBC aggregation (RBC Agg), RBC deformability index (Tk), and oxygen delivery index (ODI). Therefore, we aimed to investigate the effects of altered Al, Mn, and Se levels on number, structure, and function of RBCs (Hct, blood and plasma viscosity (BV and PV, respectively), RBC Agg, Tk, ODI) in smokers without diagnosis of chronic obstructive pulmonary disease (COPD) in a study group (n = 128) categorized as ex-smokers (ES), smokers (S), and healthy controls (HC). Elements were analyzed in serum using ICP-OES. BV and PV were measured via Brookfield and Harkness viscometers at 37 °C, respectively. Smokers had statistically higher serum Al and Mn levels, BV, RBC, Hgb, Hct, PV, fibrinogen, RBC Agg, Tk45, and pulmonary blood flow rate, but lower serum Se levels and ODI45 values versus HC. In conclusion, increased Al, Mn, and hemorheological parameters and decreased Se and ODI45 might result from inflammatory response in defense mechanism in smokers without diagnosis of COPD. Our results point out that serum Al, Mn, and Se with hemorheological parameters may be beneficial markers of tissue oxygenation and defense mechanism before the clinic onset of COPD in smokers.

  相似文献   

15.
Liposome-encapsulated Hb (LEH) is being developed as an artificially assembled, low-toxicity, and spatially isolated Hb-based oxygen carrier (HBOC). Standard methods of evaluating oxygen carriers are based on surrogate indicators of physiology in animal models of shock. Assessment of actual delivery of oxygen by HBOCs and resultant improvement in oxygen metabolism at the tissue level has been a technical challenge. In this work, we report our findings from 15O-positron emission tomographic (15O-PET) evaluation of LEH in a rat model of 40% hypovolemic shock. In vitro studies showed that PEGylated LEH formulation containing approximately 7.5% Hb and consisting of neutral lipids (distearoylphosphatidylcholine:cholesterol:alpha-tocopherol, 51.4:46.4:2.2) efficiently picks up 15O-labeled oxygen gas. The final preparation of LEH contained 5% human serum albumin to provide oncotic pressure. Cerebral PET images of anesthetized rats inhaling 15O-labeled O2 gas showed efficient oxygen-carrying and delivery capacity of LEH formulation. From the PET images, we determined cerebral metabolic rate of oxygen (CMR(O2)) as a direct indicator of oxygen-carrying capacity of LEH as well as oxygen delivery and metabolism in rat brain. Compared with control fluids [saline and 5% human serum albumin (HSA)], LEH significantly improved CMR(O2) to approximately 80% of baseline level. Saline and HSA resuscitation could not improve hypovolemia-induced decrease in CMR(O2). On the other hand, resuscitation of shed blood was the most efficient in restoring oxygen metabolism. The results suggest that 15O-PET technology can be successfully employed to evaluate potential oxygen carriers and blood substitutes and that LEH resuscitation in hemorrhage enhances oxygen delivery to the cerebral tissue and improves oxygen metabolism in brain.  相似文献   

16.
Abstract

Further research on the germination of Cercis siliquastrum L. Effect of gibberellic acid (GA3) and role of endosperm in dormancy.—In order to locate the causes of the dormancy in Cercis siliquastrum L., researches have been carried out also on non-scarified seeds without integument, as well as on isolated embryos.

We have noted that gibberellic acid can substitute the cold treatment to interrupt the dormancy and we have also investigated the optimal concentrations.

The results we have obtained do not show the inhibition to be located in the integument and point out a determinant role of the endosperm.

Histological investigations are being carried out to study better the possible occurrence of a mechanical restraint imposed by the albumen on the non-dormant embryo.  相似文献   

17.
Abstract

Hematological and biochemical profiles commonly are required in equine medicine. We studied hematological parameters including red blood cells (RBC), white blood cells (WBC), hemoglobin (Hb), hematocrit (PCV), differential leukocyte counts, mean cell volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) in thoroughbred foals at different ages and for both sexes. Sixty healthy thoroughbred foals, 1 day, 3 days and 1 year old were used. Each age group consisted of 10 male and 10 female animals. We found significant differences related to age in RBC values of females, PCV, MCV values of males, WBC, neutrophil percentages, lymphocyte percentages, monocyte percentages of females, and eosinophil percentages and basophil percentages. Significant differences related to gender were found only with regard to PCV at 1 year and WBC at 1 day. The hematological parameters of thoroughbred foals up to one year old may be useful for evaluating and monitoring the health of these animals.  相似文献   

18.
Abstract

Background

It has been demonstrated that oxidative stress can induce red blood cell rigidity and haemolysis, which in turn can cause hyperviscosity and hyperbilirubinaemia, respectively. However, haemolysis may be associated with a low level of haemoglobin, which reduces whole blood viscosity (WBV). Bilirubin can behave as antioxidant or oxidant, and one uncharted course for diagnostic pathology is how or whether bilirubinaemia and viscosity are associated. Further, oxidative stress is now being assessed using lipoprotein-a (Lp(a)), among other things but whether it is associated with blood viscosity has not been established.

Aim

This study investigates the association and correlation of haemoglobin level and WBV with serum Lp(a) and bilirubin levels in a general population of patients.

Materials and methods

Sixty-eight cases that were tested for Lp(a), concomitantly with full blood count and liver function, in our archived clinical pathology database were used in this study. WBV levels were determined using a validated formula. Multivariate and univariate analyses as well as correlation were performed.

Results

WBV was found to be significantly associated with bilirubin (P < 0.02), but not with Lp(a). Haemoglobin concentration was inversely correlated with Lp(a) (P < 0.04), but not with bilirubinaemia.

Conclusion

This pilot study suggests that hyperbilirubinaemia and hyperviscosity are associated and positively correlated. Consideration of whether serum bilirubin (as an indirect index of oxidative stress) can be used in combination with WBV (as index of macrovascular effect of oxidative stress) to assess oxidative damage is recommended.  相似文献   

19.
Purpose: Elevated serum creatine and higher handgrip strength are individually associated with better health profiles yet the link between two variables remains unknown. In this cross-sectional study, we evaluated serum creatine levels in relation to handgrip strength in a cohort of 130 young healthy adults (61 women and 69 men; age 23.3?±?2.6?years), while controlling for age, gender, fat-free mass and biomarkers of creatine metabolism as effect modifiers.

Materials and methods: Serum creatine, creatinine and guanidinoacetic acid (GAA) levels were measured with liquid chromatography-tandem mass spectroscopy, while handgrip strength was assessed with a hydraulic hand dynamometer.

Results: Hierarchical multiple regression revealed that our model as a whole explained 79.9% of the variance in handgrip strength (p?p?p?>?0.05).

Conclusions: Having higher blood creatine appears to be unrelated with better physical performance in young healthy adults. Serum creatine was not a reliable marker of muscular fitness in this population.  相似文献   

20.
Abstract

A detailed comparison of the hybridisation characteristics of oligonucleotides with 4-hydroxy-N-acetylprolinol or 3-hydroxy-N-acetylprolinol as sugar substitute, reveals dramatic differences. The 4-HO oligonucleotides are able to form stable complexes which are in general duplexes when natural nucleic acids are used as the complement, and the system has a strong preference for isochiral interaction. For the 3-HO oligonucleotides on the other hand complexes are generally weak, triple stranded, and often isochiral and heterochiral hybrids have a similar stability.  相似文献   

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