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Venous thromboembolism (VTE) is associated with a high risk of morbidity and mortality. However, data on the association between oral anticoagulants and the hazards of VTE complications in Taiwanese patients with VTE is limited. This study aimed to compare the hazards of recurrent VTE, bleeding, and mortality between patients with VTE receiving rivaroxaban, a non-vitamin K antagonist oral anticoagulant (NOAC), and those receiving heparin or low-molecular-weight heparin (LMWH) followed by warfarin. Patients with VTE treated with rivaroxaban, or heparin or LMWH followed by warfarin were enrolled from 2 million random samples from Taiwan's National Health Insurance database between 2013 and 2016. Hazards of recurrent VTE (deep vein thrombosis and pulmonary embolism), major bleeding, and mortality in rivaroxaban and warfarin users were investigated. Survival analyses were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Users of rivaroxaban (183) and warfarin (456) were included in the study. Patients receiving rivaroxaban did not have significantly lower hazards of developing recurrent VTE (HR, 0.72 [CI, 0.37-1.37], P = .31) and mortality (HR, 0.86 [CI, 0.49-1.50], P = .59) than those receiving heparin or LMWH followed by warfarin. In addition, the hazard ratio of major bleeding was not significantly different between the 2 regimens (HR, 1.80 [CI, 0.39-8.29], P = .45). Rivaroxaban was not associated with lower risks of recurrent VTE and mortality and higher hazards of major bleeding than heparin or LMWH followed by warfarin in Taiwanese patients with VTE. Clinicians may tailor oral anticoagulants for VTE patients according to the patient's characteristics, cost-effectiveness and healthcare system policy.

The aim of this study was to use a network meta-analysis (NWA) to evaluate the relative efficacy and safety of various neuraminidase inhibitors (NAIs) in reducing the duration of influenza symptoms, and thereby, informing the selection of suitable therapeutic regimens for patients with influenza. We conducted a systematic review of randomized controlled trials comparing the clinical effects of four NAIs administered to patients with influenza and placebo. Relevant studies were found in the PubMed and Cochrane databases. Unpublished studies were collected from the ClinicalTrials.gov registry and through hand searching. We carried out NWA to compare the different regimens with each other and across subgroups of age and medical status (high-risk patients). A total of 58 two-arm studies were identified. Five regimens were efficacious in reducing the time to alleviation of influenza symptoms in all populations; this efficacy was comparable. No significant improvements were seen in combination therapy groups. The mean difference in the time to alleviation of symptoms ranged from 12.78 to 19.51 h. According to the summarized mean difference and surface under the cumulative ranking curve (SUCRA), peramivir (SUCRA = 82.6%), zanamivir (SUCRA = 64%), and oseltamivir (SUCRA = 55.1%) were the three top-ranking drugs for treating influenza. Zanamivir and peramivir were the preferred pharmacologic intervention among all investigated interventions based on the calculated "value preference of SUCRA." This study is a network meta-analysis to explore the therapeutic effects of NAIs in patients with influenza. Peramivir might be the best choice for reducing the time to alleviation of symptoms.

The initiation of atherosclerosis involves up-regulation of molecules such as E-selectin, VCAM-1, and ICAM-1. The progression of atherosclerosis is linked to proliferation and migration of vascular smooth muscle cell via MMP-2 and MMP-9 activities. However, the etiology of atherosclerosis concerning plasticizers is unknown. We evaluated β-thujaplicin in preventing the development of atherosclerosis in a model induced by pro-inflammatory cytokines. Moreover, we established a new atherosclerosis model in vascular smooth muscle cells (VSMC) exposed to a common contact plasticizer, di(2-ethylhexyl)phthalate (DEHP). SEVC4-10 endothelial cells were treated with 50% RAW conditioned medium and A7r5 VSMC was treated with the plasticizer, with/without β-thujaplicin (4 or 12 μM). Production of E-selectin, ICAM-1, and VCAM-1 in SEVC4-10 cells as well as MMP-2/MMP-9 (both expression and activity) in VSMC were monitored. Results showed that the conditioned medium induced E-selectin and ICAM were significantly prevented by β-thujaplicin. However, inhibition on the production of VCAM by β-thujaplicin was only seen in a concentration of 12 μM. Both concentrations of β-thujaplicin also significantly prevented DEHP-induced MMP-2 and MMP-9 expression and activities. Evidence uncovers that β-thujaplicin has additional factors in amelioration of atherosclerosis and corroborates that β-thujaplicin is a strong candidate in preventing the initiation and progression of atherosclerosis.

Ethnopharmacological relevance Salvia miltiorrhiza Bunge (Danshen), a traditional Chinese medicine, has demonstrated in modern studies for its pharmacological activities in treatments of CNS disorders like insomnia, dysphoria. However, its application on anxiolytic effect from the ethanol extract of Salvia miltiorrhiza Bunge (SMEtOH) has not yet been reported. Materials and methods This study investigated the anxiolytic effect of the SMEtOH using the elevated plus-maze test (EPM) and the hole-board test (HBT) with diazepam and buspirone as positive controls. Also, the spontaneous locomotor activity of mice had been investigated in the open field. Further, we have illustrated the anxiolytic mechanisms of SMEtOH with its influencing upon GABAergic and/or serotonergic nervous systems via a method that SMEtOH was co-administered with flumazenil, a benzodiazepine (BZD) antagonist, or a drug (WAY-100635), a selective 5HT1A receptor antagonist. Results In hole-board test, results presented that SMEtOH increased head-dip counts and duration time. On the other hand, a decrease in spontaneous locomotor activity was observed. In the EPM test, SMEtOH increased the percentage of open-arm entries and the percentage of time spent in open arms. However, when SMEtOH co-administered with flumazenil or WAY-100635, the anxiolytic effect of SMEtOH was significantly counteracted. Conclusion From these results, we can conclude that the anxiolytic mechanism of SMEtOH is exerted through an activation of the BZD and 5HT1A receptors.

Proliferation and migration of vascular smooth muscle cells (VSMC) are important in the development and/or progression of many cardiovascular diseases, including atherosclerosis. Evidence shows that matrix metalloproteinase (MMP)-2 and MMP-9 are related to the pathogenesis of atherosclerosis. The expressions of MMP-2 and MMP-9 in atherosclerosis are regulated via various pathways, such as p38 mitogen activated protein kinase (MAPK), extracellular signal regulated kinase 1 and 2 (ERK1/2), Akt, and nuclear factor kappa (NF-κB). Di(2-ethylhexyl) phthalate (DEHP) has been shown to induce atherosclerosis by increasing tumor necrosis factor (TNF)-α, interleukin (IL)-6, and intercellular adhesion molecule (ICAM) productions. However, whether DEHP poses any effects on MMP-2 or MMP-9 expression in VSMC has not yet been answered. In our studies, rat aorta VSMC was treated with DEHP (between 2 and 17.5 ppm) and p38 MAPK, ERK1/2, Akt, NF-κB, and MMP-2 and MMP-9 proteins and activities were measured. Results showed that the presence of DEHP can induce higher MMP-2 and MMP-9 expression than the controls. Similar results on MMP-regulating proteins, i.e., p38 MAPK, ERK1/2, Akt, and NF-κB, were also observed. In summary, our current results have showed that DEHP can be a potent inducer of atherosclerosis by increasing MMP-2 and MMP-9 expression at least through the regulations of p38 MAPK, ERK1/2, Akt, and NF-κB.

The inflammation process in large vessels involves the up-regulation of vascular adhesion molecules such as endothelial cell selectin (E-selectin), intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) which are also known as the markers of atherosclerosis. We have reported that Chlorella 11-peptide exhibited effective anti-inflammatory effects. This peptide with an amino sequence Val-Glu-Cys-Tyr-Gly-Pro-Asn-Arg-Pro-Gln-Phe was further examined for its potential in preventing atherosclerosis in this study. In particular, the roles of Chlorella 11-peptide in lowering the production of vascular adhesion molecules, monocyte chemoattractant protein (MCP-1) and expression of endothelin-1 (ET-1) from endothelia (SVEC4-10 cells) were studied. The production of E-selectin, ICAM-1, VCAM-1 and MCP-1 in SVEC4-10 cells was measured with ELISA. The mRNA expression of ET-1 was analyzed by RT-PCR and agarose gel. Results showed that Chlorella 11-peptide significantly suppressed the levels of E-selectin, ICAM, VCAM, MCP-1 as well as ET-1 gene expression. The inhibition of ICAM-1 and VCAM-1 production by Chlorella 11-peptide was reversed in the presence of protein kinase A inhibitor (H89) which suggests that the cAMP pathway was involved in the inhibitory cause of the peptide. In addition, this peptide was shown to reduce the extent of increased intercellular permeability induced by combination of 50% of lipopolysaccharide (LPS)-activated RAW 264.7 cells medium and 50% normal SEVC cell culture medium (referred to as 50% RAW-conditioned medium). These data demonstrate that Chlorella 11-peptide is a promising biomolecule in preventing chronic inflammatory-related vascular diseases.

A one-step preparation of nanoparticles with poly(lactide-co-glycolide) (PLGA) pre-modified with polyethylenimine (PEI) is better in requirements for DNA delivery compared to those prepared in a two-step process (preformed PLGA nanoparticles and subsequently coated with PEI). The particles were prepared by emulsification of PLGA/ethyl acetate in an aqueous solution of PVA and PEI. DLS, AFM and SEM were used for the size characteristics. The cytotoxicity of PLGA/PEI nanoparticles was detected by MTT assay. The transfection activity of the particles was measured using pEGFP and pβ-gal plasmid DNA. Results showed that the PLGA/PEI nanoparticles were spherical and non-porous with a size of about 0.2 μm and a small size distribution. These particles had a positive zeta potential demonstrating that PEI was attached. Interestingly, the zeta potential of the particles (from one-step procedure) was substantially higher than that of two-step process and is ascribed to the conjugation of PEI to PLGA via aminolysis. The PLGA/PEI nanoparticles were able to bind DNA and the formed complexes had a substantially lower cytotoxicity and a higher transfection activity than PEI polyplexes. In conclusion, given their small size, stability, low cytotoxicity and good transfection activity, PLGA/PEI-DNA complexes are attractive gene delivery systems.

Solar UV radiation damages human skin by affecting skin tone and resiliency and leads to premature aging (photoaging). The skin damage is caused by the activation of the AP-1 transcription factor, which increases matrix metalloproteinase (MMP) expression and collagen degradation. An increase of interleukin (IL)-6 is also correlated with the activation of MMP-1 expression. β-thujaplicin has shown both acaricidal and antimicrobial activities. Also, β-thujaplicin has been shown to be protective against apoptosis due to the oxidative effects of UV irradiation. However, the effect of β-thujaplicin on UVB-induced MMPs had not been investigated. In this study, after UVB exposure, MMP-1 and IL-6 production in human skin fibroblasts was examined in the presence of β-thujaplicin, vitamin C, and vitamin E. The expression of MMP-1, MMP-3, tissue inhibitor of metalloproteinase (TIMP-1, TIMP-3) and procollagen mRNA was also investigated. Results showed that UVB-induced MMP-1 production was suppressed by the β-thujaplicin treatment in a dose-dependent manner, but not by vitamin C and vitamin E. β-thujaplicin also prevented the up-regulation of MMP-1 and MMP-3 mRNA. Moreover, the UVB-suppressed procollagen gene expression was restored to normal by β-thujaplicin. Neither UVB nor β-thujaplicin affected the mRNA expression of TIMP-1 and TIMP-3. The IL-6 production induced by UVB was lower in β-thujaplicin treated fibroblasts than in the controls. In conclusion, this study shows the capability of β-thujaplicin in preventing MMP-1 production due to UVB irradiation via inhibition of MMP gene expression. Importantly, the UVB-suppressed procollagen gene expression can be restored to normal by β-thujaplicin. These findings indicate that β-thujaplicin is a promising and potent agent to inhibit UVB-induced MMP-1 and MMP-3 gene expression in skin fibroblasts.

Two new urethane-based acrylates (UAA and PEG-UAA) were synthesized as polymer blocks. The chemical composition of the two monomers was confirmed by IR and NMR. After cross-linking these blockers by radical polymerization, “hexamethylene PU” [poly(hexamethylene-urethane)] and “PEG-hexamethylene PU” [PEG-poly(hexa-methylene-urethane)] were obtained. The platelet adhesion and platelet activation of these polymers were evaluated in the presence of Platelet Rich Plasma (PRP) blood. The relative blood clotting indexes of the polymers were determined to measure their capability of reducing thrombogenicity. The hemolysis of red blood cells was also assessed to examine the haemocompatibility of the polymers. The hexamethylene PU and PEG-hexamethylene PU showed less platelet adhesion, platelet activation, blood clotting and hemolysis than a commercial PU (Tecoflex). The liquid crystal molecule, cholesteryl oleyl carbonate (COC), showed further improved biocompatibility to human blood, after COC was embedded in the PU polymers. PEG-hexamethylene PU + 10% COC demonstrated the best activity in reducing thrombogenicity and the best haemocompatibility. The inclusion of PEG segments into the PEG-UAA structure increased its hydrophilicity. The methylene bis(cyclohexyl) segments in Tecoflex PU decreased haemocompatibility. These observations are in good agreement with performed contact angle measurements. The PEG-hexamethylene PU loaded with COC might be a promising material for applications in bioengineering.

Polymer-stabilized iron oxide nanoparticles could be used as contrast agents in magnetic resonance imaging (MRI) due to their unique superparamagnetism. Here we demonstrate a quaternized chitosan, i.e. N-[(2-hydroxy-3-trimethylammonium)propyl] chitosan chloride (HTCC), encapsulating superparamagnetic iron oxide (SPIO), with very low toxicity and less effect on cell growth. HTCC has quaternary amino groups introduced into the chitosan chain, and such modification of chitosan should render it soluble in water. Most importantly, the HTCC―SPIO thus prepared has the ability to accelerate the MRI relaxation processes of surrounding water protons, resulting in enhanced MRI contrast (R2: y = 0.1076x ― 0.0092; R1: y = 0.008x ― 0.0005). The iron content quantified by Prussian blue staining and MRI revealed a positive correlation between Prussian blue positive cells and the change of MRI signal intensity. Also, transmission electron microscopy and element mapping confirmed intracellular metal-like spots as internalized iron oxide. Such findings support the use of these quaternized chitosan-stabilized iron oxide nanoparticles as a potential MRI contrast agent for cell tracking.

Euphorbia hirta L. has been widely used in India and Chinese society. The molecular pharmacology basis of its anti-inflammatory effect is revealed in this work. The ethanol extract of Euphorbia hirta L. (Eh) and its active component were studied in lipopolysaccharide (LPS)-activated macrophage cells (RAW 264.7) as an established inflammation model. After activation, nitric oxide (NO) production and expression of iNOS protein and iNOS mRNA were measured by using a colorimetric assay (Griess reagent), western blotting, and reverse transcription polymerase chain reaction (RT-PCR), respectively. The alteration in the content of PGE(2), TNFalpha, and IL-6 was concurrently monitored by ELISA. In results, we found that in the concentration range without showing cytotoxicity, Eh produced a remarkable anti-inflammatory effect via its active component of beta-amyrin and showed a dose-related inhibition of LPS-induced NO production. This phenomenon is in accordance with a substantial inhibition of iNOS protein. However, the expression of iNOS gene was unaffected by Eh treatments. Compared with indomethacin, Eh has much more potency and a specific action of NO inhibition but Eh works less specifically on PGE(2), IL-6, and TNF-alpha inhibition. The extract of Euphorbia hirta L. and its component beta-amyrin are able to block most of the iNOS protein functions and NO induction, and could therefore be new selective NO inhibitors with great potential in treating arthritis inflammation.

Polyurethanes (PUs) are a class of biodegradable polymers that have been applied as tissue-engineering materials with minimum toxicity. In our study, a new series of cationic PUs containing tertiary amines in the backbone and primary, secondary and tertiary amines in the side chains (PU1, PU2 and PU3, respectively) was synthesized and used as nonviral vectors for gene delivery. In addition, we introduced glycidol into the structure of PU for greater solubility and biocompatibility and grafted various amines in the side chains (PUg1, PUg2, PUg3). The structural characteristics of PUs and the physicochemical properties of their formed complexes with DNA were determined and correlated with their transfection efficiency. The results reveal that PU1, PU3, PUg1 and PUg3 could bind with DNA and yielded positively charged complexes with a condensed size required for transfection. These PUs are considered to be noncytotoxic (hundred times less) compared to polyethylenimine (PEI) or poly(2-dimethylaminoethyl methacrylate), (PDMAEMA). The hydrolytical degradation studies indicate that PU-glycidyl systems (PUg1 and PUg3) can be degraded in 20 mM HEPES buffer at pH 7.4 in approximately 8 h but that PU1 and PU3 lasted much longer. PUg1 and PUg3 are the best amongst cationic PUs to transfect DNA into COS-7 cells with an efficacy comparable to the well-known gene carrier PDMAEMA. In addition, PUg1 and PUg3 possess greater biocompatibility and biodegradability. A new way to prepare cationic polymers without cytotoxicity but with highly transfecting activity could be very helpful to the in vivo gene transfection where large amounts of cationic polymers are required.

An important advantage of polymer-based gene delivery systems over viral transfection systems is that transient gene expression without the safety concerns can be achieved. In addition to the polymeric systems to deliver DNA, therapeutic ultrasound is potentially useful because ultrasound energy can be transmitted through the body without damaging tissues and could be applied on a restricted area where the desired DNA is to be expressed. In this study, bioeffects of ultrasound on the transfection efficiency and cytotoxicity of DNA-polymer complexes on mammalian cells (HEK-293 and COS-7 cell lines) were investigated. Polymer-DNA ratios for optimal transfection efficiency and the size of PEI/DNA or PDMAEMA/DNA complexes were found not affected by ultrasound treatment. Also, electrophoresis results indicate that the tertiary DNA structure was not influenced by ultrasound when exposed up to 10 seconds. More importantly, cationic polymer-mediated cell transfection was significantly enhanced and reached a 150% increase by using ultrasound. Cytotoxicity of HEK-293 and COS-7 cell lines was not observed after ultrasound. Therefore, these results indicate that clinical applications of ultrasound could be used as a safe and efficient method for non-viral gene delivery

The aim of this study is to investigate how the presence of liquid crystal, cholesteryl oleyl carbonate, embedded into polymers (PMMA, Eb270, PU) affects the biocompatibility of composite membranes with human blood. The effects of different surface textures of composite membranes on platelet adhesion and platelet activation were evaluated as well. The adhesion and geometric deformation of platelets were demonstrated by SEM. The quantitative assay of platelet activation was determined by measuring the production of P-Selectin, and by measurement of the blood clotting index when PRP blood was incubated with pure polymer films and composite membranes. Moreover, the hemolysis studies on the damage to red blood cells were performed to gain information on the hemocompatibility of these biomaterials. The results showed that inclusion of cholesteryl oleyl carbonate (COC) embedded in composite membranes, improves their biocompatibility with respect to a substantial reduction of platelet adhesion and the controlled decrease of platelet activation. As the COC content of composite membranes was increased, the value of the blood clotting index increased and the production of P-Selectin decreased. The results also showed that the presence of COC resulted in a decrease of hemolysis ratios. Comparing among three different composite membranes, the best biocompatibility is achieved when PU/COC> or ==Eb270/COC>PMMA/COC. The in vitro studies performed in this work suggest that it may be reasonable to use liquid crystal COC as a mean of surface modification to improve the blood compatibility of biopolymers.

Chlorella, a type of unicellular fresh water algae, has been a popular foodstuff in Japan and Taiwan. Studies have shown the hypoglycemic effects of Chlorella in alloxan-induced and Streptozocin (STZ)-induced diabetic animals. However, the mechanisms by which Chlorella treatment affects blood glucose homeostasis have not been studied. Diabetes in ICR mice was induced by injection of STZ. Lipogenesis in vivo was measured by incorporating 3H-H2O into lipids in brown and white adipose tissues. Glucose uptake in the liver and soleus muscles was measured by assaying 2-deoxy-D-[1,2-3H] glucose levels. The effects of Chlorella on serum non-esterified fatty acids (NEFA) were measured with commercial assay kits. Insulin-stimulated lipogenic rates in brown and white adipose tissues were unaffected by Chlorella. However, Chlorella increased 2-deoxyglucose uptake in the livers and soleus muscles in normal and STZ mice compared to that in their respective controls (p < 0.01). In addition, fasting NEFA levels were lower in Chlorella-treated STZ mice compared to H2O-treated STZ mice (p < 0.005). The current results suggest that the hypoglycemic effects of Chlorella are due to an enhancement of glucose uptake in the liver and in soleus muscles. The improved insulin sensitivity after Chlorella treatment could be also due to lower NEFA levels, since insulin sensitivity is usually blunted by elevated NEFA in diabetes.

The effects of Chlorella pyrenoidosa on serum lipid profiles, after concomitant long-term treatment of high-fat diet (HFD) in rats and hamsters was studied. Wistar rats and Syrian hamsters were fed with or without various concentrations of Chlorella pyrenoidosa contained high-fat diet (CHFD) for 2, 4 and 8 weeks prior to assay of serum lipids. Fasting triglycerides, total cholesterol, and LDL cholesterol as well as HDL cholesterol levels in high-fat diet treated rats and hamster were determined. Results showed that triglycerides, total cholesterol and LDL cholesterol levels in HFD treated rats and hamsters were increased from the normal rodent diet (NRD) treated controls after 2, 4, and 8-week treatments. However, the presence of Chlorella pyrenoidosa in high-fat diets significantly decreased the levels of triglycerides, total cholesterol and LDL cholesterol with comparison to HFD group in rats and hamsters. The total cholesterol/HDL ratios, an indication of occurrence of coronary heart disease, were decreased in all CHFD treated grouped rats and hamsters which suggests administration of Chlorella pyrenoidosa could lower the occurring risk of heart diseases. In conclusion, Chlorella pyrenoidosa has the ability to prevent dyslipidemia in chronic high-fat fed animals and could be potential in use to prevent intestinal absorption of redundant lipid from our daily intake and subsequently to prevent hyperlipidemia as well as atherosclerosis.

Dexamethasone (DXM) is known as an immunosuppressive drug used for inflammation control. In the present study, we attempted to examine whether DXM administration could attenuate the hypercoagulable state and the overproduction of pro-inflammatory cytokines, improve arterial hypotension, cerebral ischemia and damage, and vital organ failure in a rat model of heat stroke. The results indicated that all the rats suffering from heat stroke showed high serum levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), accompanied with increased prothrombin time, activated partial thromboplastin time and D-D dimer, and decreased protein C. During the induction period of heat stroke, plasma levels of blood urea nitrogen (BUN), creatinine, glutamic oxaloacetic transaminase (SGOT), glutamic pyruvic transaminase (SGPT), and alkaline phosphatase (ALP), were consistently increased. High striatal levels of glycerol, glutamate, and lactate/pyruvate were simultaneously detected. On the contrary, the mean arterial pressure, plasma levels of interleukin-10 (IL-10), and local cerebral blood flow at the striatum were all decreased. Importantly, intravenous administration of DXM substantially ameliorated the circulatory dysfunction, systematic inflammation, hypercoagulable state, cerebral ischemia and damage during the induction period of heat stroke. These findings demonstrated that DXM may be an alternative therapy that can ameliorate heat stroke victims by attenuating activated coagulation, systemic inflammation, and vital organ ischemia/injury during heat stroke.

Untreated (control) obese CBA mice had lower hormone-sensitive lipase (HSL) activity and cAMP levels in brown adipose tissue than normal lean mice, but white adipose tissue HSL activity and cAMP were similar in obese and lean mice. In the obese mice, chronic ethanol treatment increased HSL activity and cAMP levels in both brown and white adipose tissue to above the levels in lean mice. In the lean mice, chronic ethanol only stimulated white adipose tissue. UK 14304 [5-bromo-6-(2-imidazolin-2-ylamino)-quinoxaline: 2 mg/kg] inhibited HSL activity in both brown and white adipose tissues in lean mice, but a higher dose (3 mg/kg) was required to produce the same inhibition in obese mice. After chronic ethanol adipose tissues were more sensitive to UK 14304; only half the dose being required to produce the same level of lipase inhibition. We propose that, although chronic ethanol consumption increases cAMP levels in adipose tissue, particularly in obese mice, it also sensitizes the tissues to alpha(2)-adrenoceptor stimulation. These effects may explain the increased sympathetic nervous system activity observed in alcohol withdrawal.

Acute S 22068 (24 mg/kg po) improved glucose tolerance and increased insulin sensitivity, assessed as the acute blood glucose response to exogenous insulin. The same acute dose did not stimulate insulin secretion or induce hypoglycemia in fed animals. Comparison of acute S 22068 to equipotent doses (with respect to effect on glucose tolerance) of gliclazide (2 mg/kg) and metformin (60 mg/kg) found S 22068 to be similar to metformin with respect to its effects on basal glucose levels (BGL) and insulin sensitivity. This also suggests that S 22068 acts by a mechanism which does not involve insulin release. Acute or sub-chronic S 22068 (14 days at 25 mg/day) had no effect on brown adipose tissue (BAT) or white adipose tissue (WAT) lipogenesis, an insulin-sensitive metabolic pathway. Sub-chronic treatment with S 22068 did not alter body weight (BW) or food intake, and resulted in tolerance to its effects on glucose metabolism and insulin sensitivity. These findings suggest that S 22068 is similar in effect to metformin, and is not insulinogenic, in contrast to the sulfonylureas or putative I 3 imidazoline site ligands.

Acute SR 58611A (0.25 mg kg−1), was effective in reducing the blood glucose response to a glucose tolerance test (GTT) in normal lean (control) and spontaneously obese/diabetic CBA/Ca mice and to be equipotent to 1.25 mg kg−1 glibenclamide in lean mice. Neither brown (BAT) nor white (WAT) adipose tissue lipogenesis was altered by acute SR 58611A (2–8 mg kg−1) in lean mice, but both increased significantly at the higher doses in the obese mice. Acute SR 58611A produced a hypoglycaemia 40 min after dosing in lean and obese animals, the duration and potency of which was less than that of glibenclamide. Plasma insulin levels increased 20 min after acute SR 58611A and glibenclamide in lean and obese mice. Chronic treatment (0.25 mg kg−1, 15 days) with SR 58611A increased its effectiveness in improving glucose tolerance, but did not affect the body weight (BW) or food intake of either lean or obese mice. Acute and chronic SR 58611A prolonged the hypoglycaemic effect of exogenous insulin in lean but not obese mice. In fed and fasted lean mice and in fasted obese mice chronic SR 58611A produced an acute hypoglycaemia 30 min post administration which was greater than after a single dose. SR 58611A maintained its effectiveness in improving glucose tolerance in lean and obese mice over a dosing period of 15 days. The improvement in glucose tolerance was achieved at a dose less than that required to stimulate adipose tissue lipogenesis and which did not affect food intake or body weight. British Journal of Pharmacology (1999) 128, 1586–1592; doi:10.1038/sj.bjp.0702946

Diurnal variation in blood and plasma ethanol levels (BACs) has been observed in animals undergoing chronic ethanol treatment, but the information available is insufficient to determine whether the different patterns seen are due to differences in ethanol administration schedules or to strain of the animal. In this study, we have compared plasma ethanol levels in males of two mouse strains with no innate preference for ethanol, TO and CBA, during two commonly employed chronic ethanol treatment schedules. Ethanol was administered in solution as sole drink (CED) (10% or 20% w/v ethanol) for 4 weeks, or in liquid diet form (ELD), (3.5% w/v ethanol for 2 days, then 7% for 5 days). Mice were housed eight per cage on a 12-h light cycle (0900-2100 hours). Plasma ethanol concentration was monitored over the 24-h period. Activity of liver alcohol dehydrogenase (ADH) was measured between 0900 and 1100 hours. CBA mice showed greater variability in body weights than TO mice, which weighed more throughout the period of study and had significantly higher total energy intakes. TO mice consumed more ELD than CBA mice. Following an initial 2-day period of 3.5% ELD, both strains decreased their diet intake when ethanol content of the diet was increased to 7% w/v, which resulted in weight loss. Mice on the CED schedules decreased their fluid intake with increasing concentration of ethanol in the drinking solution. Highest daily ethanol intakes were observed in mice on ELD (19.1 +/- 1.7 and 22.2 +/- 0.6 g/kg body weight in CBA and TO mice, respectively). Marked diurnal variation in plasma ethanol levels was observed, which was dependent on the treatment schedule, strain and method of ethanol administration. Highest levels were found in mice on the ELD schedule (104.8 +/- 7.7 mM in CBA mice, 113.5 +/- 14.5 mM in TO mice), peaking at 1900 and at 0900 hours in CBA and TO mice, respectively. Lower plasma ethanol concentrations were reached in mice on the CED schedules, peaking at midnight (34.6 +/- 8.1 mM and 35.4 +/- 8.8 mM in CBA and TO mice on 20% CED, respectively, and 3.7 +/- 1.2 mM and 6.6 +/- 2.1 mM in CBA and TO mice on 10% CED). Naive CBA mice had slightly higher liver ADH activity as compared to their TO counterparts. No effect of 10% CED on liver ADH activity was found in either mouse strain. In conclusion, we have confirmed the importance of monitoring plasma ethanol levels during chronic treatment, as there is marked diurnal variation, dependent on the light/dark cycle. Factors such as strain of the animal and the method of delivery of ethanol are also important, whereas liver ADH plays a minor role. Monitoring the daily ethanol consumption is insufficient to predict the resulting plasma levels of the drug.

Polyurethanes (PUs) are formed by a reaction between isocyanates and diols to yield polymers with urethane bonds (-NH-COO-) in their main chain. A great variety of building blocks is commercially available that allows the chemical and physical properties of PUs to be tailored to their target applications, particularly for the biomedical and pharmaceutical fields. This article reviews the synthesis and characterization of PUs and PU-copolymers, as well as their in vitro and in vivo biodegradability and biocompatibility. Particular emphasis is placed on the use of PUs for the controlled release of drugs and for the (targeted) delivery of biotherapeutics.

Acute injection of either noradrenaline or isoprenaline in mice activated both brown (BAT) and white (WAT) adipose tissue hormone-sensitive lipase activity (HSL). Dose-response studies indicated that isoprenaline (0.05-0.15 mg/kg) produced a dose-dependent activation of HSL in both BAT and WAT, whereas SR 58611A produced no change in HSL in WAT over a dose range (1-5 mg/kg) which, at the same time, dose-dependently increased HSL activity in BAT. The other beta 3-adrenoceptor agonists, ZD 7114 (10 mg/kg) and BRL 35135 A (5 mg/kg) also selectively increased HSL activity in BAT, these doses having previously been shown to stimulate lipogenesis in vivo. Higher doses of ZD 7114 and BRL 35135 produced no further increase in HSL activity and, in the case of BRL 35135, provoked symptoms of non-selective beta-adrenoceptor activation. The increase in HSL activity could be prevented by pretreating the mice with propranolol, 10 mg/kg, i.p., 30 min prior to the agonist. The activation of HSL activity by the beta 3-adrenoceptor agonists was associated with an increase in tissue cAMP production which was also prevented by pretreatment with propranolol. The degree of cAMP accumulation was least with BRL 35135 and greatest with ZD 7114. We conclude that, in the mouse adipocyte, the atypical beta-adrenoceptor (beta 3) is present in BAT, but is not present or functional in WAT.

UVC irradiation induces oxidative stress and leads to cell death through an apoptotic pathway. This apoptosis is caused by activation of caspase-3 and formation of poly(ADP-ribose) polymerase-1 (PARP-1). In this study, the underlying mechanisms of Chlorella derived peptide (CDP) activity against UVC-induced cytotoxicity were investigated. Human skin fibroblasts were treated with CDP, vitamin C, or vitamin E after UVC irradiation for a total energy of 15 J/cm2. After the UVC exposure, cell proliferation and caspase-3 activity were measured at 12, 24, 48, and 72 h later. Expression of phosphorylated FADD and cleaved PARP-1 were measured 16 h later. DNA damage (expressed as pyrimidine (6-4) pyrimidone photoproducts DNA concentration) and fragmentation assay were performed 24 h after the UVC exposure. Results showed that UVC irradiation induced cytotoxicity in all groups except those treated with CDP. The caspase-3 activity in CDP-treated cells was inhibited from 12 h onward. Expression of phosphorylated FADD and cleaved PARP-1 were also reduced in CDP-treated cells. Moreover, UVC-induced DNA damage and fragmentation were also prevented by the CDP treatment. This study shows that treatment of CDP provides protective effects against UVC-induced cytotoxicity through the inhibition of caspase-3 activity and the reduction of phosphorylated FADD and cleaved PARP-1 expression.

Euphorbia is a genus of plants belonging to the family Euphorbiaceae. Botanist and taxonomist Carl Linnaeus assigned the name Euphorbia to the entire genus in the physician's honor. Euphorbia hirta is a very popular herb amongst practitioners of traditional herb medicine, widely used as a decoction or infusion to treat various ailments including intestinal parasites, diarrhoea, peptic ulcers, heartburn, vomiting, amoebic dysentery, asthma, bronchitis, hay fever, laryngeal spasms, emphysema, coughs, colds, kidney stones, menstrual problems, sterility and venereal diseases. Moreover, the plant is also used to treat affections of the skin. In this chapter we explore those investigations related to their pharmacological activities (see the section 2.2).

There is evidence that increased plasma cytokines, elevated brain levels of monoamines and hydroxyl radical production may be implicated in pathogenesis during heat stroke in rats. Acute treatment with a combined therapeutic approach has been repeatedly advocated in cerebral ischemia experiments. The aim of this study was to investigate whether the combined agent (mannitol and dexamethasone) has beneficial efficacy to improve the survival time (ST) and heat stroke-induced damage in experimental heat stroke. Urethane-anesthetized rats underwent instrumentation for the measurement of colonic temperature, mean arterial pressure (MAP), striatal cerebral blood flow (CBF), heart rate, and neuronal damage score. The rats were exposed to an ambient temperature (43 degrees C) to induce heat stroke. Concentrations of the ischemic and damage markers, dopamine, serotonin, and hydroxyl radical production in corpus striatum, and the plasma levels of tumor necrosis factor-alpha (TNF-alpha) were observed during heat stroke. After the onset of heat stroke, the heat stroke rats display decreased MAP, decreased CBF, increased the plasma levels of TNF-alpha, increased cerebral striatal monoamines and hydroxyl radical production release, and severe cerebral ischemia and neuronal damage compared with those of normothermic control rats. However, immediate treatment with the combined agent confers significant protection against heat stroke-induced arterial hypotension, systemic inflammation, cerebral ischemia, cerebral monoamines and hydroxyl radical production overloads, and improves neuronal damage and the ST in heat stroke rats. Our data suggest that administration of this combined agent seems to have more effective to ameliorate the heat stroke-induced neuronal damage and prolong the ST.

Solar UV radiation damages human skin, affecting skin tone and resiliency, and leading to premature ageing (photoageing). Skin damage by oxidants may lead to activation of PKC, thus increasing matrix metalloproteinase (MMPs) expression and collagen degradation. Administration of Chlorella has been shown to play some biochemical functions as well as in vitro inhibition of MMP1 activity. MMP1 secretion was evaluated following PMA treatment or UVB irradiation in the presence of Resilient Factor (RF, aqueous extract fraction of Chlorella), vitamin C, or vitamin E in human skin fibroblasts. Expression levels of MMP1 and elastin protein and of MMP1, TIMP1, and pro-collagen mRNA were also investigated. PMA-induced MMP1 production, protein, and gene expression were suppressed in the presence of RF. Elastin protein diminished after UVB exposure and RF treatment appeared able to counteract the effect of UVB irradiation. Our results also suggest that RF may increase pro-collagen mRNA expression following UVB exposure. This study shows that application of RF prevents MMP1 production via the inhibition of protein and gene expression. In addition, RF prevents the UVB-suppressed elastin protein and pro-collagen gene expression. These findings indicate that RF may exert a protective effect against UVB irradiation-induced damage in the skin.

Inefficient release of polymer/DNA complexes from endocytic vesicles into the cytoplasm and the cytotoxic nature of cationic polymers are two of the primary causes of poor gene delivery. EG-polyurethane [poly(ethylene glycol)-PU, Poly 1], EGDM-polyurethane [poly(ethylene glycol), 2-(dimethylamino)ethylamine-PU, Poly 2], and MDEADM-polyurethane [N-methyldiethanolamine, 2-(dimethylamino)ethylamine-PU, Poly 3] were designed in this study to overcome these obstacles. The structural characteristics of polyurethanes and physicochemical properties of their formed complexes with DNA were determined to correlate their transfection efficiency. The results revealed that Poly 2 and Poly 3 could bind with plasmid DNA and yield positively charged complexes with a size required for transfection. Poly 3 showed the best in buffering capacity and its formed complexes with DNA could transfect COS-7 cells better than those of Poly 2 and Poly 1. This study reveals that the amine groups in the polymeric structure and the buffer capacity of a polymeric transfectant would affect its potential in DNA delivery. Also the size and binding properties of DNA and polymeric transfectants can be in correlation to the transfection efficiency of resulting DNA/polymer complexes.

The time course of the effects of ethanol withdrawal on brown and white adipose tissue hormone-sensitive lipase, cAMP production, and phosphodiesterase have been investigated after chronic drinking or liquid diet schedules. Chronic drinking significantly reduced brown adipose tissue hormone-sensitive lipase activity and cAMP levels from control. During withdrawal, there was a rebound increase to 200% control, peaking 9 h into withdrawal. White adipose tissue hormone-sensitive lipase activity and cAMP accumulation were significantly raised by both treatment schedules. Ethanol liquid diet produced a significant fall in adipose tissue hormone-sensitive lipase activity and cAMP accumulation. In brown fat, there was a rebound increase in hormone-sensitive lipase activity and cAMP; in white fat, no rebound was observed. In brown fat, the reductions in hormone-sensitive lipase activity and cAMP accumulation after chronic drinking coincided with an increase in phosphodiesterase activity. In white fat, the rise in cAMP and hormone-sensitive lipase activation coincided with a decrease in phosphodiesterase activity. We conclude that the effects of chronic ethanol on hormone-sensitive lipase activity are cAMP-dependent and mediated via alterations in phosphodiesterase activity.

1. The effects of two chronic ethanol treatment schedules, which produce different plasma ethanol concentrations, on the specific activities of adipose tissue lipoprotein lipase (LPL) and hormone-sensitive lipase (HSL) have been investigated in brown and white fat. 2. Mice provided with 20% ethanol solution as sole drinking fluid for 28 days consumed between 13 and 15 g ethanol kg-1 body weight day-1 over days 22-28. The mean plasma ethanol concentration was 4.94 +/- 1.4 mM (n = 8) at 09 h 00 min on day 28 when the lipase assays were performed. Mice given ethanol in a liquid diet for 7 days consumed between 15 and 18 g ethanol day-1 over days 3-7. The mean plasma ethanol concentration was 15.9 +/- 4.7 mM (n = 8) at 09 h 00 min on day 7. These concentrations of ethanol had no effect on the activity of either LPL or HSL in vitro. 3. LPL activity in white and brown fat (expressed as nmol fatty acids released h-1 mg-1 acetone powder) was unaltered 60 min following an acute injection of ethanol (2.5 g kg-1, i.p.) which produced a mean blood ethanol level of 37.5 +/- 6.7 mM. HSL activity in white fat (expressed as nmol fatty acid released h-1 mg-1 protein) was also unaffected by this acute dose of ethanol, but the activity in brown fat was significantly reduced: 3.07 +/- 0.30 (n = 8) after ethanol compared to 4.36 +/- 0.25 (n = 12) in controls (P0.01). 4. LPL activity in white fat was little altered by either of the chronic ethanol treatment schedules whilst LPL activity in the brown fat from the same animals was significantly increased compared to the respective control values: 0.27 +/- 0.03 (ethanol drinking), control: 0.16 +/- 0.01; 0.79 +/- 0.14 (ethanol liquid diet), control: 0.39 +/- 0.05. 5. HSL activity in white fat was significantly increased by the chronic drinking treatment (7.7 +/- 0.5; control: 3.78 +/- 0.17, n = 8) at the same time that the activity in brown fat was reduced (3.76 +/- 0.2; control: 4.74 +/- 0.16). The ethanol liquid diet also reduced HSL activity in brown fat but had negligible effect in white fat. 6. The effects of the two chronic ethanol treatments on adenosine 3':5'-cyclic monophosphate (cyclic AMP) accumulation in brown and white fat were very similar, both qualitatively and quantitatively, to the effects on HSL. 7. It has been shown that brown and white adipose tissues respond differently to the presence of chronic ethanol and that the response is dependent both upon the concentration of ethanol and the nature of the diet with which the ethanol is administered. The effects of ethanol on adipose tissue HSL activity appear to be mediated via changes in the tissue cyclic AMP level and, in this respect, brown fat is more sensitive to ethanol than white fat.

The effects of a chronic ethanol drinking schedule (20% solution for 6 weeks) on energy balance and carbohydrate and lipid metabolism have been investigated in lean (32-36 g) and obese-diabetic (40-44 g) CBA/Ca mice. The untreated obese-diabetic mice exhibited hyperglycaemia, hypertriglyceridaemia, hyper-insulinaemia and insulin resistance. The chronic ethanol treatment, which yielded plasma ethanol levels of between 1 and 11 mM, lowered the blood glucose, plasma insulin and triacylglycerol levels towards normal in the obese mice, but did not affect these parameters in the lean mice. The body weight of the obese mice tended to return to normal during the 6-week drinking period, although their total energy intake (9.2-10.0 kJ/g/week, food plus ethanol-derived calories) was almost double that of the lean mice (4.8-5.4 kJ/g/week). The blood glucose response to acute insulin injection, which was significantly reduced in the obese mice, became indistinguishable from the response of normal mice after chronic ethanol treatment. Soleus muscle glycogen synthesis in both lean and obese mice was not significantly altered by ethanol drinking, but brown adipose tissue lipogenesis was significantly increased (by 50%) in the obese mice. It is proposed that ethanol is acting chronically to restore insulin sensitivity in the obese diabetic mice at doses which have little or no effect in normal lean animals. This action is exerted, at least in part, at the level of brown adipose tissue lipogenesis.

Background Increased systemic cytokines and elevated brain levels of monoamines, and hydroxyl radical productions are thought to aggravate the conditions of cerebral ischemia and neuronal damage during heat stroke. Dexamethasone (DXM) is a known immunosuppressive drug used in controlling inflammation, and hydroxyethyl starch (HES) is used as a volume-expanding drug in cerebral ischemia and/or cerebral injury. Acute treatment with a combined therapeutic approach has been repeatedly advocated in cerebral ischemia experiments. The aim of this study is to investigate whether the combined agent (HES and DXM) has beneficial efficacy to improve the survival time (ST) and heat stroke-induced cerebral ischemia and neuronal damage in experimental heat stroke. Methods Urethane-anesthetized rats underwent instrumentation for the measurement of colonic temperature, mean arterial pressure (MAP), local striatal cerebral blood flow (CBF), heart rate, and neuronal damage score. The rats were exposed to an ambient temperature (43 degrees centigrade) to induce heat stroke. Concentrations of the ischemic and damage markers, dopamine, serotonin, and hydroxyl radical productions in corpus striatum, and the serum levels of interleukin-1 beta, tumor necrosis factor-alpha and malondialdehyde (MDA) were observed during heat stroke. Results After heat stroke, the rats displayed circulatory shock (arterial hypotension), decreased CBF, increased the serum levels of cytokines and MDA, increased cerebral striatal monoamines and hydroxyl radical productions release, and severe cerebral ischemia and neuronal damage compared with those of normothermic control rats. However, immediate treatment with the combined agent at the onset of heat stroke confers significant protection against heat stroke-induced circulatory shock, systemic inflammation; cerebral ischemia, cerebral monoamines and hydroxyl radical production overload, and improves neuronal damage and the ST in rats. Conclusions Our results suggest that the combination of a colloid substance with a volume-expanding effect and an anti-inflammatory agent may provide a better resuscitation solution for victims with heat stroke.