Enhancement of tumor tropism of mPEGylated nanoparticles by anti-mPEG bispecific antibody for ovarian cancer therapy.

Ovarian cancer is highly metastatic, with a high frequency of relapse, and is the most fatal gynecologic malignancy in women worldwide. It is important to elevate the drug susceptibility and cytotoxicity of ovarian cancer cells, thereby eliminating resident cancer cells for more effective therapeutic efficacy. Here, we developed a bispecific antibody (BsAb; mPEG × HER2) that can easily provide HER2+ tumor tropism to mPEGylated liposomal doxorubicin (PLD) and further increase the drug accumulation in cancer cells via receptor-mediated endocytosis, and improve the cytotoxicity and therapeutic efficacy of HER2+ ovarian tumors. The mPEG × HER2 can simultaneously bind to mPEG molecules on the surface of PLD and HER2 antigen on the surface of ovarian cancer cells. Simply mixing the mPEG × HER2 with PLD was able to confer HER2 specificity of PLD to HER2+ ovarian cancer cells and efficiently trigger endocytosis and enhance cytotoxicity by 5.4-fold as compared to non-targeted PLD. mPEG × HER2-modified PLD was able to significantly increase the targeting and accumulation of HER2+ ovarian tumor by 220% as compared with non-targeted PLD. It could also significantly improve the anti-tumor activity of PLD (P < 0.05) with minimal obvious toxicity in a tumor-bearing mouse model. We believe that the mPEG × HER2 can significantly improve the therapeutic efficacy, potentially reduce the relapse freqency and thereby achieve good prognosis in ovarian cancer patients.

Double attack strategy for leukemia using a pre-targeting bispecific antibody (CD20 Ab-mPEG scFv) and actively attracting PEGylated liposomal doxorubicin to enhance anti-tumor activity.

BACKGROUND: Tumor-targeted nanoparticles hold great promise as new tools for therapy of liquid cancers. Furthermore, the therapeutic efficacy of nanoparticles can be improved by enhancing the cancer cellular internalization. METHODS: In this study, we developed a humanized bispecific antibody (BsAbs: CD20 Ab-mPEG scFv) which retains the clinical anti-CD20 whole antibody (Ofatumumab) and is fused with an anti-mPEG single chain antibody (scFv) that can target the systemic liquid tumor cells. This combination achieves the therapeutic function and simultaneously "grabs" Lipo-Dox® (PEGylated liposomal doxorubicin, PLD) to enhance the cellular internalization and anticancer activity of PLD. RESULTS: We successfully constructed the CD20 Ab-mPEG scFv and proved that CD20 Ab-mPEG scFv can target CD20-expressing Raji cells and simultaneously grab PEGylated liposomal DiD increasing the internalization ability up to 60% in 24 h. We further showed that the combination of CD20 Ab-mPEG scFv and PLD successfully led to a ninefold increase in tumor cytotoxicity (LC50: 0.38 nM) compared to the CD20 Ab-DNS scFv and PLD (lC50: 3.45 nM) in vitro. Importantly, a combination of CD20 Ab-mPEG scFv and PLD had greater anti-liquid tumor efficacy (P = 0.0005) in Raji-bearing mice than CD20 Ab-DNS scFv and PLD. CONCLUSION: Our results indicate that this "double-attack" strategy using CD20 Ab-mPEG scFv and PLD can retain the tumor targeting (first attack) and confer PLD tumor-selectivity (second attack) to enhance PLD internalization and improve therapeutic efficacy in liquid tumors.

Electrical control of spins and giant g-factors in ring-like coupled quantum dots.

Emerging theoretical concepts for quantum technologies have driven a continuous search for structures where a quantum state, such as spin, can be manipulated efficiently. Central to many concepts is the ability to control a system by electric and magnetic fields, relying on strong spin-orbit interaction and a large g-factor. Here, we present a mechanism for spin and orbital manipulation using small electric and magnetic fields. By hybridizing specific quantum dot states at two points inside InAs nanowires, nearly perfect quantum rings form. Large and highly anisotropic effective g-factors are observed, explained by a strong orbital contribution. Importantly, we find that the orbital contributions can be efficiently quenched by simply detuning the individual quantum dot levels with an electric field. In this way, we demonstrate not only control of the effective g-factor from 80 to almost 0 for the same charge state, but also electrostatic change of the ground state spin.

Reliable sonographic features for nodal thyroglobulin to diagnose recurrent lymph node metastasis from papillary thyroid carcinoma.

OBJECTIVES: Ultrasound-guided aspiration cytology (US-FNAC) was previously used to diagnose lymph node metastasis of papillary thyroid carcinoma (PTC). Combined US-FNAC with nodal thyroglobulin (LN-FNA-Tg) significantly improved the diagnostic rate. However, diagnostic accuracy depends on proper node selection. Therefore, it is crucial to choose the nodes with reliable sonographic features to guide clinician for confirmation. DESIGN AND SETTING: Retrospective cohort study was carried out in one medical centre from 2011 to 2014. PARTICIPANTS: A total of 148 patients with PTC, being treated by total thyroidectomy and radioiodine, were assessed for potential nodal metastases by ultrasound. MAIN OUTCOME MEASURES: Lymph nodes with cystic content, peripheral hypervascularity, calcification, hyperechoic content, the absence of hilum and Solbiati index < 2 indicated risk of malignancy. US-FNAC and LN-FNA-Tg were both performed. Positive nodal metastasis was further confirmed by dissection. Risk impact of these sonographic features on LN-FNA-Tg to diagnose nodal metastasis was tested by logistic regression analysis based on the significance in both univariate and multivariate models. RESULTS: Overall, 49 lymph nodes were documented as recurrent nodal metastasis. LN-FNA-Tg greater than serum thyroglobulin and higher than 1 ng/mL achieved 100% of diagnostic rate for recurrent nodal metastasis. The malignant sonographic features that significantly cohered with positive LN-FNA-Tg were cystic and hyperechoic content and lack hilum, in sequence. CONCLUSIONS: LN-FNA-Tg is an excellent tool to quantitatively diagnose nodal metastasis. To achieve ideal diagnosis, the most reliable sonographic features were cystic content, hyperechoic content and the absence of hilum in lymph nodes, but not calcification or Solbiati index < 2.

Nationwide cohort study of hip fractures: time trends in the incidence rates and projections up to 2035.

SUMMARY: A growing elderly population is expected worldwide, and the burden of hip fractures on health care system will continue to increase. By 2035, there will be a 2.7-fold increase in the number of hip fractures in Taiwan. The study provides quantitative basis for the future distribution of medical resources. INTRODUCTION: Hip fractures have long been recognized as a major public health concern. The study aimed to determine time trends in the incidence of hip fractures and to forecast the number of hip fractures expected in Taiwan up to 2035. METHODS: A nationwide survey was conducted using data from the Taiwan National Health Insurance Research Database from 2004 to 2011. A total of 141,397 hip fractures were identified, with a mean of 17,675 fractures/year. Annual incidences of hip fractures were calculated and tested for trends. Projections of the incidence rates of hip fractures and bed days associated with hip fractures were calculated using Poisson regression on the historical incidence rates in combination with population projections from 2012 to 2035. RESULTS: The incidence rates of hip fracture during 2004-2011 were 317 and 211 per 100,000 person-years among women and men, respectively. Over this 8-year period, the age-standardized incidence of hip fracture decreased by 13.4% among women and 12.2% among men. Despite the decline in the age-standardized incidence, the absolute number of hip fractures increased owing to the aging population. The number of hip fractures is expected to increase from 18,338 in 2010 to 50,421 in 2035-a 2.7-fold increase. The number of bed days for 2010 and 2035 was estimated at 161,248 and 501,995, respectively, representing a 3.1-fold increase. CONCLUSIONS: The socioeconomic impact of hip fractures will be high in the near future. This study provides a quantitative basis for future policy decisions to serve this need.

NO-releasing xanthine KMUP-1 bonded by simvastatin attenuates bleomycin-induced lung inflammation and delayed fibrosis.

BACKGROUND AND PURPOSE: Pulmonary fibrosis (PF) is a progressing lung injury initiated by pulmonary inflammation (PI). Bleomycin (BLM) is the most common pathogenesis of PF through early PI and extensive extracellular matrix deposition. This study is aimed to determine whether NO-releasing KMUP-1 inhibits PI and PF, and if so, the benefits of KMUP-1S resulted from simvastatin (SIM)-bonding to KMUP-1. EXPERIMENT APPROACH: C57BL/6 male mice were intra-tracheally administered BLM (4 U/kg) at day 0. KMUP-1 (1-5 mg/kg), KMUP-1S (2.5 mg/kg), SIM (5 mg/kg), Plus (KMUP-1 2.5 mg/kg + SIM 2.5 mg/kg), and clarithromycin (CAM, 10 mg/kg) were orally and daily administered for 7 and 28 days, respectively, to mice, sacrificed at day-7 and day-28 to isolate the lung tissues, for examining the inflammatory and fibrotic signaling and measuring the cell population and MMP-2/MMP-9 activity in broncholaveolar lavage fluid (BAL). KEY RESULTS: KMUP-1 and KUP-1S significantly decreased neutrophil counts in BAL fluid. Fibroblastic foci were histologically assessed by H&E and Masson's trichrome stain and treated with KMUP-1 and references. Lung tissues were determined the contents of collagen and the expressions of TGF-ß, α-SMA, HMGB1, CTGF, eNOS, p-eNOS, RhoA, Smad3, p-Smad3, MMP-2 and MMP-9 by Western blotting analyses, respectively. These changes areregulated by NO/cGMP and inhibited by various treatments. KMUP-1 and KMUP-1S predominantly prevented HMGB1/MMP-2 expression at day-7 and reduced TGF-ß/phosphorylated Smad3 and CTGF at day-28. CONCLUSIONS AND IMPLICATIONS: KMUP-1 and KMUP-S restore eNOS, inhibit iNOS/ROCKII/MMP-2/MMP-9, attenuate histologic collagen disposition and reduce BALF inflammatory cells, potentially useful for the treatment of BLM-lung PF.

NO donor KMUP-1 improves hepatic ischemia-reperfusion and hypoxic cell injury by inhibiting oxidative stress and pro-inflammatory signaling.

This study investigates whether KMUP-1 improves hepatic ischemia-reperfusion (I/R) and hypoxic cell injury via inhibiting Nox2- and reactive oxygen species (ROS)-mediated pro-inflammation. Rats underwent ischemia by occlusion of the portal vein and hepatic artery for 45 minutes. Reperfusion was allowed for 4 h. Serum was used for analysis of aspartate aminotransferase (AST) and alanine aminotransferase (ALT). DNA extracted from liver homogenate was analyzed by electrophoresis to observe the fragmentation. Lipid peroxidation (LPO) was evaluated by measuring thiobarbituric acid-reactive substances (TBARS). NO and ROS contents were measured using Griess reagent and 2'-7'-dichlorofluorescein, respectively. Proteins levels were visualized by Western blotting. Liver damage was observed under a microscope. Intravenous KMUP-1 (0.25, 0.5 and 1 mg/kg) reduced I/R-induced ALT and AST levels, DNA fragmentation, ROS and malondialdehyde (MDA) and restored the NO levels of I/R rats. KMUP-1 protected the liver architecture from worsening of damage and focal sinusoid congestion, increased endothelium NO synthase (eNOS), guanosine 3', 5'cyclic monophosphate (cGMP), protein kinase G (PKG) and the B-cell lymphoma 2/Bcl-2-associated X protein (Bcl-2/Bax) ratio, attenuated phosphodiesterase 5A (PDE-5A) and cleaved caspase-3 expression in I/R-liver. In hypoxic HepG2 cells, KMUP-1 increased cGMP/PKG, restored peroxisome proliferator-activated receptor-gamma (PPAR-gamma) and decreased matrix metalloproteinases-9 (MMP-9), Rho kinase II (ROCK II), hypoxia-inducible factor-1alpha (HIF-1alpha) and vascular endothelium growth factor (VEGF). KMUP-1 protects liver from I/R-injury and hypoxic hepatocytes from apoptosis-associated free radical generation and pro-inflammation by restoring/increasing NO/cGMP/PPAR-gamma, reducing ROS/Nox2 and inhibiting ROCKII/MMP-9.

Eugenolol and glyceryl-isoeugenol suppress LPS-induced iNOS expression by down-regulating NF-kappaB AND AP-1 through inhibition of MAPKS and AKT/IkappaBalpha signaling pathways in macrophages.

Eugenol and isoeugenol, two components of clover oil, have been reported to possess several biomedical properties, such as anti-inflammatory, antimicrobial and antioxidant effects. This study aims to examine the anti-inflammatory effects of eugenol, isoeugenol and four of their derivatives on expression of inducible nitric oxide synthase (iNOS) activated by lipopolysaccharide (LPS) in mouse macrophages (RAW 264.7), and to investigate molecular mechanisms underlying these effects. We found that two derivatives, eugenolol and glyceryl-isoeugenol, had potent inhibitory effects on LPS-induced upregulation of nitrite levels, iNOS protein and iNOS mRNA. In addition, they both suppressed the release of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) induced by LPS. Moreover, they both attenuated the DNA binding of NF-kB and AP-1, phosphorylation of inhibitory kB-alpha (IkB-alpha), and nuclear translocation of p65 protein induced by LPS. Finally, we demonstrated that glyceryl-isoeugenol suppressed the phosphorylation of ERK1/2, JNK and p38 MAPK, whereas eugenolol suppressed the phosphorylation of ERK1/2 and p38 MAPK. Taken together, these results suggest that that eugenolol and glyceryl-isoeugenol suppress LPS-induced iNOS expression by down-regulating NF-kB and AP-1 through inhibition of MAPKs and Akt/IkB-alpha signaling pathways. Thus, this study implies that eugenolol and glyceryl-isoeugenol may provide therapeutic benefits for inflammatory diseases.

Determination of voxel phantom for reference Taiwanese adult from CT image analyses.

The International Commission on Radiological Protection Publication 103 recommended that ionising radiation doses should be assessed based on voxel phantoms. An anthropomorphic voxel phantom for the Reference Taiwanese Adult was built from analyses of computed tomography (CT) images. Thirty representative adult individuals were selected from normal patients in the hospital, with body mass index between 19.6 and 25.6 for males and 18.8 and 27.0 for females and body height between 163 and 175 cm for males and 152 and 162 cm for females. The Reference Taiwanese Adult was determined from these individuals by analysing their CT images for parameters characterising the size, position and orientation of several organs. Analysed parameters included the volume, surface area, major and minor axes, mean chord length, position relative to the body centre, and orientation with respect to the body axis, for liver, spleen, kidney, stomach, gallbladder and bladder. The person with the highest score was designated the Reference Taiwanese Adult.

KMUP-1 inhibits H441 lung epithelial cell growth, migration and proinflammation via increased NO/CGMP and inhibited RHO kinase/VEGF signaling pathways.

This study investigates whether KMUP-1 protects soluble guanylate cyclase (sGC) and inhibits vascular endothelial growth factor (VEGF) expression in lung epithelial cells in hypoxia, therapeutically targeting epithelial proinflammation. H441 cells were used as a representative epithelial cell line to examine the role of sGC and VEGF in hypoxia and the anti-proinflammatory activity of KMUP-1 in normoxia. Human H441 cells were grown in hypoxia for 24-72 h. KMUP-1 (1, 10, 100 microM) arrested cells at the G0/G1 phase of the cell cycle, reduced cell survival and migration, increased p21/p27, restored eNOS, increased soluble guanylate cyclase (sGC) and PKG and inhibited Rho kinase II (ROCK-II). KMUP-1 (0.001-0.1 microM) concentration dependently increased eNOS in normoxia and did not inhibit phosphodiesterase-5A (PDE-5A) in hypoxic cells. Hypoxia-induced factor-1alpha (HIF-1alpha) and VEGF were suppressed by KMUP-1 but not by L-NAME (100 microM). The PKG inhibitor Rp-8-CPT-cGMPS (10 microM) blunted the inhibition of ROCK-II by KMUP-1. KMUP-1 inhibited thromboxane A2-mimetic agonist U46619-induced PDE-5A, TNF-alpha (100 ng/ml)-induced iNOS, and ROCK-II and associated phospho-p38 MAPK, suggesting multiple anti-proinflammatory activities. In addition, increased p21/p27 by KMUP-1 at higher concentrations might contribute to an increased Bax/Bcl-2 and active caspase-3/procaspase-3 ratio, concomitantly causing apoptosis. KMUP-1 inhibited ROCK-II/VEGF in hypoxia, indicating its anti-neoplastic and anti-inflammatory properties. KMUP-1 inhibited TNF-alpha-induced iNOS and U46619-induced PDE-5A and phospho-p38 MAPK in normoxia, confirming its anti-proinflammatory action. KMUP-1 could be used as an anti-proinflammatory to reduce epithelial inflammation.

Activation of BKCa channels via cyclic AMP- and cyclic GMP-dependent protein kinases by eugenosedin-A in rat basilar artery myocytes.

BACKGROUND AND PURPOSE: The study investigated whether eugenosedin-A, a 5-hydroxytryptamine and alpha/beta adrenoceptor antagonist, enhanced delayed-rectifier potassium (K(DR))- or large-conductance Ca(2+)-activated potassium (BK(Ca))-channel activity in basilar artery myocytes through cyclic AMP/GMP-dependent and -independent protein kinases. EXPERIMENTAL APPROACH: Cerebral smooth muscle cells (SMCs) were enzymatically dissociated from rat basilar arteries. Conventional whole cell, perforated and inside-out patch-clamp electrophysiology was used to monitor K(+)- and Ca(2+)-channel activities. KEY RESULTS: Eugenosedin-A (1 microM) did not affect the K(DR) current but dramatically augmented BK(Ca) channel activity in a concentration-dependent manner. Increased BK(Ca) current was abolished by charybdotoxin (ChTX, 0.1 microM) or iberiotoxin (IbTX, 0.1 microM), but not affected by a small-conductance K(Ca) blocker (apamin, 100 microM). BK(Ca) current activation by eugenosedin-A was significantly inhibited by an adenylate cyclase inhibitor (SQ 22536, 10 microM), a soluble guanylate cyclase inhibitor (ODQ, 10 microM), competitive antagonists of cAMP and cGMP (Rp-cAMP, 100 microM and Rp-cGMP, 100 microM), and cAMP- and cGMP-dependent protein kinase inhibitors (KT5720, 0.3 microM and KT5823, 0.3 microM). Eugenosedin-A reversed the inhibition of BK(Ca) current induced by the protein kinase C activator, phorbol myristyl acetate (PMA, 0.1 microM). Eugenosedin-A also prevented BK(Ca) current inhibition induced by adding PMA, KT5720 and KT5823. Moreover, eugenosedin-A reduced the amplitude of voltage-dependent L-type Ca(2+) current (I(Ca,L)), but without modifying the voltage-dependence of the current. CONCLUSIONS AND IMPLICATIONS: Eugenosedin-A enhanced BK(Ca) currents by stimulating the activity of cyclic nucleotide-dependent protein kinases. Physiologically, this activation would result in the closure of voltage-dependent calcium channels and thereby relax cerebral SMCs.

San-Huang-Xie-Xin-Tang attenuates inflammatory responses in lipopolysaccharide-exposed rat lungs.

In this study, the potential anti-inflammatory effect of San-Huang-Xie-Xin-Tang (SHXT) and its main component baicalin on LPS-induced lung injury were investigated and compared to the profile of dexamethasone (DEXA) in a pre-clinical animal model. Post-treatment with SHXT (75 mg/kg), baicalin (1.5 mg/kg) and DEXA (0.5 mg/kg), significantly inhibited LPS-induced hypotension, lung edema and acute survival rates. Western blotting analysis results indicated that all of them significantly inhibited LPS-induced iNOS, TGF-beta, p38MAPK, and ICAM-1 expressions in the lung tissues. Results from ELISA analysis showed that SHXT, baicalin and DEXA all decreased plasma levels of IL-1beta, TNF-alpha, and MCP-1 caused by LPS. Based on these findings, SHXT and baicalin decreased plasma concentrations of IL-1beta, TNF-alpha, MCP-1, and expressions of TGF-beta, ICAM-1, phosphorylated p38 MAPK, and iNOS, which were associated with lung injury and lethality. These evidences indicated that SHXT and baicalin showed strong anti-inflammatory activity, similar to that observed for DEXA, and therefore implicated that herbal SHXT might be therapeutically useful for the treatment of endotoxic lung injury.

Age-dependent protection quantities for external neutron irradiation.

Based on the recommendations issued by the International Commission on Radiological Protection (ICRP), equivalent doses and effective doses for different ages are obtained for external neutron sources. The calculations at 28 neutron energies from 1 x 10(-9) MeV to 20 MeV are carried out for six irradiation geometries: AP, PA, RLAT, LLAT, ROT and ISO. An age-dependent anthropomorphic mathematical phantom series of six age groups: newborn, 1, 5, 10, 15 years old and adult is used with the Monte Carlo computer code MCNP for the dose evaluations. The results for adults are compared with those in ICRP Publication 74 and are in good agreement. At low energies the effective doses increase as the phantom age increases, but at high energics they decrease with increasing age for the AP, PA, ROT and ISO irradiation geometries. In the whole energy region the effective doses decrease as the phantom age increases for the RLAT and LLAT irradiation geometries. The age-dependent equivalent doses behave similarly to the effective doses, with some exceptions caused by the influence of the organ position.

Age-dependent protection quantities for external photon irradiation.

The age-dependent conversion coefficients of the protection quantities, the equivalent dose and the effective dose defined by the International Commission on Radiological Protection (ICRP), are obtained. A Monte Carlo computer code and the age-dependent hermaphrodite mathematical phantoms of six age groups: newborn, 1, 5, 10, 15 years old and adult are used for the evaluation. Twenty-three photon source energies from 10 keV to 10 MeV and six kinds of irradiation geometries: AP, PA, RLAT, LLAT, ROT, and ISO are chosen in the calculation. The evaluated conversion coefficients for the adult are compared with those in ICRP Publication 74 with good agreement. The conversion coefficients of the equivalent dose and the effective dose increase while the age of the phantom decreases, but with some exceptions for the AP irradiation geometry under certain conditions.

A xanthine-based KMUP-1 with cyclic GMP enhancing and K(+) channels opening activities in rat aortic smooth muscle.

1. KMUP-1 (1, 3, 5 mg kg(-1), i.v.), a xanthine derivative, produced dose-dependent sustained hypotensive and short-acting bradycardiac effects in anaesthetized rats. This hypotensive effect was inhibited by pretreatment with glibenclamide (5 mg kg(-1), i.v.). 2. In endothelium-intact or denuded aortic rings preconstricted with phenylephrine, KMUP-1 caused a concentration-dependent relaxation. This relaxation was reduced by endothelium removal, the presence of NOS inhibitor L-NAME (100 microM) and sGC inhibitors methylene blue (10 microM) and ODQ (1 microM). 3. The vasorelaxant effects of KMUP-1 was attenuated by pretreatment with various K(+) channel blockers TEA (10 mM), glibenclamide (1 microM), 4-AP (100 microM), apamin (1 microM) and charybdotoxin (ChTX, 0.1 microM). 4. Increased extracellular potassium levels (30 - 80 mM) caused a concentration-related reduction of KMUP-1-induced vasorelaxations. Preincubation with KMUP-1 (1, 10, 100 nM) increased the ACh-induced maximal vasorelaxations mediated by endogenous NO release, and enhanced the potency of exogenous NO-donor SNP. 5. The vasorelaxant responses of KMUP-1 (0.01, 0.05, 0.1 microM) together with a PDE inhibitor IBMX (0.5 microM) had an additive action. Additionally, KMUP-1 (100 microM) affected cyclic GMP metabolism since it inhibited the activity of PDE in human platelets. 6. KMUP-1 induced a dose-related increase in intracellular cyclic GMP levels in rat A10 vascular smooth muscle (VSM) cells, but not cyclic AMP. The increase in cyclic GMP content of KMUP-1 (0.1 - 100 microM) was almost completely abolished in the presence of methylene blue (10 microM), ODQ (10 microM), and L-NAME (100 microM). 7. In conclusion, these results indicate that KMUP-1 possesses the following merits: (1) stimulation of NO/sGC/cyclic GMP pathway and subsequent elevation of cyclic GMP, (2) K(+) channels opening, and (3) inhibition of PDE or cyclic GMP breakdown. Increased cyclic GMP display a prominent role in KMUP-1-induced VSM relaxations.

Prevention of cerebral vasospasm by a capsaicin derivative, glyceryl nonivamide, in an experimental model of subarachnoid hemorrhage.

BACKGROUND: Cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) remains a major complication in patients suffering from SAH. In our previous study, we reported that stimulating vascular K(+) channel activity prevented the development of cerebral vasospasm. Recent evidence indicates that glyceryl nonivamide (GLNVA), a capsaicin derivative, has a vasorelaxant effect on the aortic vascular smooth muscle due to the release of coronary calcitonin gene-related peptide, which in turn stimulates K(+) channel opening. The purpose of the present study was to examine the preventive effects of GLNVA on vasospasm. METHODS: New Zealand white rabbits were subjected to experimental SAH by injecting autologous blood into the cisterna magna. GLNVA or vehicle was injected intrathecally immediately after the induction of SAH. All animals were killed by perfusion-fixation at 48 hours after SAH. The basilar arteries were removed and sectioned, and their cross-sectional areas were measured. RESULTS: The average cross-sectional areas of basilar arteries were reduced by 69% and 71% in the SAH only and SAH plus vehicle groups, respectively, when compared with the healthy controls. After treatment with 0.35, 1.75, and 3.5 mg/kg GLNVA in rabbits subjected to SAH the average cross-sectional area was decreased by 46%, 12% and 2%, respectively, when compared with the healthy controls. The protective effect of GLNVA achieved statistical significance at all dosages. Morphologically, corrugation of the internal elastic lamina of vessels was often observed in the vehicle-treated group, but was not prominent in the GLNVA-treated groups or healthy controls. CONCLUSION: The findings showed that GLNVA dose-dependently attenuated cerebral vasospasm after SAH in the rabbit. These results suggest that intrathecal administration of GLNVA could be an effective strategy for preventing cerebral vasospasm after SAH.

A new aspect of view in synthesizing new type beta-adrenoceptor blockers with ancillary antioxidant activities.

A series of vanilloid-type beta-adrenoceptor blockers derived from antioxidant traditional Chinese herbal medicines were synthesized and tested for their antioxidant and adrenoceptor antagonistic activities. They all possessed significant beta-adrenoceptor blocking activities under in vitro experiments and radioligand binding assays. In addition, some compounds were further examined in in vivo tests and produced antagonist effects matching that of propranolol and labetalol by measurements of antagonism toward (-)isoproterenol-induced tachycardia and (-)phenylephrine-induced pressor responses in anesthetized rats. Furthermore, all of the compounds had antioxidant effects inherited from their original structures. In conclusion, compound 11 had the most potent beta-adrenoceptors blocking activity, 12 and 13 possessed high cardioselectivity, whereas 14, 15 and 16 possessed additional alpha-adrenoceptor blocking activity and 15 is the most effective antioxidant of all. The antioxidant activity may be due to their alpha and beta unsaturated side chain at position 1 and ortho-substituted methoxy moiety on 4-phenoxyethylamine.

Identification of HIV-1 integrase inhibitors via three-dimensional database searching using ASV and HIV-1 integrases as targets.

Integration of viral DNA into the host cell genome is a critical step in the life cycle of HIV. This essential reaction is catalyzed by integrase (IN) through two steps, 3'-processing and DNA strand transfer. Integrase is an attractive target for drug design because there is no known cellular analogue and integration is essential for successful replication of HIV. A computational three-dimensional (3-D) database search was used to identify novel HIV-1 integrase inhibitors. Starting from the previously identified Y3 (4-acetylamino-5-hydroxynaphthalene-2,7-disulfonic acid) binding site on the avian sarcoma virus integrase (ASV IN), a preliminary search of all compounds in the nonproprietary, open part of the National Cancer Institute 3-D database yielded a collection of 3100 compounds. A more rigorous scoring method was used to rescreen the 3100 compounds against both ASV IN and HIV-1 IN. Twenty-two of those compounds were selected for inhibition assays against HIV-1 IN. Thirteen of the 22 showed inhibitory activity against HIV-1 IN at concentrations less than 200 microM and three of them showed antiviral activities in HIV-1 infected CEM cells with effective concentrations (EC50) ranging from 0.8 to 200 microM. Analysis of the computer-generated binding modes of the active compounds to HIV-1 IN showed that simultaneous interaction with the Y3 site and the catalytic site is possible. In addition, interactions between the active compounds and the flexible loop involved in the binding of DNA by IN are indicated to occur. The structural details and the unique binding motif between the HIV-1 IN and its inhibitors identified in the present work may contribute to the future development of IN inhibitors.

The interference of uptake of thallium-201 in cultured rat myocardial cells with existence of potassium related pharmaceuticals--a preliminary report.

Thallium-201 myocardial perfusion imaging is wildly used to detect and assess the extent of jeopardized myocardial ischemia in the coronary artery disease and the viability of myocardium post infarction. In recent years, there has been a great deal of pharmacological development of blockers and openers of potassium channel. In this study, we will discuss the interference of uptake of thallium-201 ion in cultured neonatal rat myocytes with existence of a variety of pharmacological agents. The cultures of neonatal rat myocardial cells were incubated with different agents such as potassium chloride, sodium-potassium ATPase pump inhibitor (ouabain), cesium compound, variable potassium channel blockers (4 AP, TEA and glibenclamide) and their openers (minoxidil, and cromakalim). The radioactivity of intracellular thallium-201 that could enter rat myocardial cells was detected by gamma counter sixty minutes after thallium-201 was added. In this study we found that thallium and potassium ions behave in an analogous manner in cultured rat myocardial cells. Both 2.5 mM and 5 mM concentration of extracellular potassium ion significantly result in reduction of thallium-201 ion influx in rat myocardial cells. 0.5 mM ouabain, an inhibitor of sodium-potassium ATPase pump, reduced about 40% of influx of thallium-201 ion in cultured rat myocardial cells via active transport. Combination of both potassium ion and ouabain inhibit most of thallium-201 ions influx in myocardial cells, but it is not completely inhibited. Cesium, a potassium antagonist, also interferes with the uptake of thallium-201 in cultured rat myocytes in our study. The most interesting finding in our investigation is that potassium channel blockers such as TEA and glibenclamide, inhibit the influx of thallium-201 in myocytes. However, potassium channel openers have no overt effect on influx of thallium-201 in cultured rat myocytes. We indirectly observe about 60% of influx of thallium-201 ion into cultured rat myocardial cells via active sodium-potassium ATPase pump. Potassium, cesium and potassium channel blockers, such as TEA and glibenclamide, inhibited the different percentage of influx of thallium-201 in cultured rat myocardial cells in this study.

Vanidipinedilol: a vanilloid-based beta-adrenoceptor blocker displaying calcium entry blocking and vasorelaxant activities.

Calcium channel and beta-adrenoceptor blockade have proved highly useful in antihypertensive therapy. Studies of the mechanisms of action of vanidipinedilol that combine these effects within a single molecule are described here. Intravenous injection of vanidipinedilol (0.1, 0.25, 0.5, 1.0, and 2.0 mg/kg) produced dose-dependent hypotensive and bradycardic responses, significantly different from nifedipine-induced (0.5 mg/kg, i.v.) hypotensive and reflex tachycardic effects in pentobarbital-anesthetized Wistar rats. A single oral administration of vanidipinedilol at doses of 10, 25, and 50 mg/kg dose-dependently reduced blood pressure with a decrease in heart rate in conscious spontaneously hypertensive rats (SHRs). In the isolated Wistar rat atrium, vanidipinedilol (10(-7), 10(-6), and 10(-5) M) competitively antagonized the (-)isoproterenol-induced positive chronotropic and inotropic effects and inhibited the increase in heart rate induced by Ca2+ (3.0-9.0 mM) in a concentration-dependent manner. The parallel shift to the right of the concentration-response curve of (-)isoproterenol and CaCl2 suggested that vanidipinedilol possessed beta-adrenoceptor-blocking and calcium entry-blocking activities. On tracheal strips of reserpinized guinea pig, cumulative doses of vanidipinedilol (10(-10) to 3x10(-6) M) produced dose-dependent relaxant responses. Preincubating the preparation with ICI 118,551 (10(-10), 10(-9), 10(-8) M), a beta2-adrenoceptor antagonist, shifted the vanidipinedilol concentration-relaxation curve significantly to a region of higher concentrations. These results implied that vanidipinedilol had a partial beta2-agonist activity. In the isolated thoracic aorta of rat, vanidipinedilol had a potent effect inhibiting high-K+-induced contractions. KCI-induced intracellular calcium changes of blood vessel smooth muscle cell (A7r5 cell lines) determined by laser cytometry also was decreased after administration of vanidipinedilol (10(-8), 10(-7), 10(-6) M). Furthermore, the binding characteristics of vanidipinedilol and various antagonists were evaluated in [3H]CGP-12177 binding to ventricle and lung and [3H]nitrendipine binding to cerebral cortex membranes in rats. The order of potency of beta1- and beta2-adrenoceptor antagonist activity against [3H]CGP-12177 binding was (-)propranolol (pKi, 8.59 for beta1 and 8.09 for beta2) > vanidipinedilol (pKi, 7.09 for beta1 and 6.64 for beta2) > atenolol (pKi, 6.58 for beta1 and 5.12 for beta2). The order of potency of calcium channel antagonist activity against [3H]nitrendipine binding was nifedipine (pKi, 9.36) > vanidipinedilol (pKi, 8.07). The ratio of beta1-adrenergic-blocking/calcium entry-blocking selectivity is 0.1 and indicated that vanidipinedilol revealed more in calcium entry-blocking than in beta-adrenergic-blocking activities. It has been suggested that vanidipinedilol-induced smooth muscle relaxation may involve decreased entry of Ca2+ and partial beta2-agonist activities. In conclusion, vanidipinedilol is a nonselective beta-adrenoceptor antagonist with calcium channel blocking and partial beta2-agonist associated vasorelaxant and tracheal relaxant activities. Particularly, the vasodilator effects of vanidipinedilol are attributed to a synergism of its calcium entry blocking and partial beta2-agonist activities in the blood vessel. A sustained bradycardic effect results from beta-adrenoceptor blocking and calcium entry blocking, which blunts the sympathetic activation-associated reflex tachycardia in the heart.