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31.
The majority of the findings concerning arterial physiology and pathophysiology originate from studies with experimental animals, while only limited information exists about the functional characteristics of human arteries. Therefore, the aim of the present work was to compare the control of vascular tone in vitro in mesenteric arterial rings of corresponding size (outer diameter 0.75–1 mm) from humans and Wistar-Kyoto rats. The relaxations to acetylcholine (ACh) were clearly less marked in the mesenteric arteries of humans when compared with rats. How-ever, when calcium ionophore A23187 was used as the vasodilator, the endothelium-mediated relaxations did not significantly differ between these species. The NO synthase inhibitor N G-nitro-l-arginine methyl ester (l-NAME) attenuated the relaxations to ACh and A23187 in both groups. The endothelium-independent relaxations to the β-adrenoceptor agonist isoprenaline and the nitric oxide (NO)-donor nitroprusside were somewhat lower in human arteries, while vasodilation induced by the K+ channel opener cromakalim was similar between humans and rats. Arterial contractile sensitivity to noradrenaline and serotonin was slightly lower in human vessels, whereas contractile sensitivity to KCl was similar between these species. The contractions induced by cumulative addition of Ca2+ with noradrenaline as the agonist were effectively inhibited in both groups by the calcium channel blocker nifedipine, the effect of which was clearly more pronounced in human arteries. In conclusion, the control of vascular tone of isolated arteries of corresponding size from humans and rats appeared to be rather similar. The most marked differences between these species were the impaired endothelium-mediated dilation to ACh and the more pronounced effect of nifedipine on the Ca2+-induced contractions in human arteries. Received: 1 October 1998 / Accepted: 4 January 1999  相似文献   
32.
Soapfishes contain peptide toxins (grammistins) in the skin secretion. Two grammistins (Gs 1 and Gs 2) and six grammistins (Pp 1, Pp 2a, Pp 2b, Pp 3, Pp 4a and Pp 4b) have already been isolated from Grammistes sexlineatus and Pogonoperca punctata, respectively. In this study, five grammistins (Gs A-E), together with grammistins Gs 1 and Gs 2, were further isolated from G. sexlineatus by gel filtration and reverse-phase HPLC. Sequence analyses revealed that grammistins Gs A (28 residues) and Gs C (26 residues) are analogous to grammistin Pp 3 and grammistin Gs B (12 residues) to grammistin Pp 1, while grammistins Gs D (13 residues) and Gs E (13 residues) are identical with grammistins Pp 1 and Pp 2b, respectively. Grammistins Gs A-C exhibited antibacterial activity with a broad spectrum against nine species of bacteria in common with the other grammistins but had no hemolytic activity differing from the other grammistins. Grammistins Gs A-E, Gs 1 and Gs 2 could release carboxyfluorescein entrapped within liposomes made of either phosphatidylcholine or phosphatidylglycerol/phosphatidylcholine (3:1), demonstrating their membrane-lytic activity. However, no clear relationship between the membrane-lytic activity and the biological activity of grammistins was recognized.  相似文献   
33.
Amphetamines are commonly used to treat attention-deficit hyperactivity disorder, but are also widely abused. They are employed in schizophrenia-related animal models as they disrupt the prepulse inhibition (PPI) of the acoustic startle response. The behavioral effects of amphetamines have mainly been attributed to changes in dopamine transmission, but they also involve increases in the synaptic concentrations of norepinephrine (NE). alpha2-Adrenoceptors (alpha2-ARs) regulate the excitability and transmitter release of brain monoaminergic neurons mainly as inhibitory presynaptic auto- and heteroreceptors. Modulation of acoustic startle and its PPI by the alpha2A-AR subtype was investigated with mice lacking the alpha2A-AR (alpha2A-KO) and their wild-type (WT) controls, without drugs and after administration of the alpha2-AR agonist dexmedetomidine or the antagonist atipamezole. The interaction of D-amphetamine (D-amph) and the alpha2-AR-noradrenergic neuronal system in modulating startle reactivity and in regulating brain monoamine metabolism was assessed as the behavioral and neurochemical responses to D-amph alone, or to the combination of D-amph and dexmedetomidine or atipamezole. alpha2A-KO mice were supersensitive to both neurochemical and behavioral effects of D-amph. Brain NE stores of alpha2A-KO mice were depleted by D-amph, revealing the alpha2A-AR as essential in modulating the actions of D-amph. Also, increased startle responses and more pronounced disruption of PPI were noted in D-amph-treated alpha2A-KO mice. alpha2A-AR also appeared to be responsible for the startle-modulating effects of alpha2-AR drugs, since the startle attenuation after the alpha2-AR agonist dexmedetomidine was absent in alpha2A-KO mice, and the alpha2-AR antagonist atipamezole had opposite effects on the startle reflex in alpha2A-KO and WT mice.  相似文献   
34.
PURPOSE: Nitroglycerin may improve the response to chemotherapy in advanced non-small cell lung cancer. The effects and mechanisms of nitroglycerin on the enhancement of chemosensitivity to docetaxel and carboplatin regimen (DCb) in patients with lung adenocarcinoma have not been reported. EXPERIMENTAL DESIGN: Seventeen patients with operable lung adenocarcinoma and stable angina pectoris were selected to investigate the effects of nitroglycerin on immunoreactivity for hypoxia-inducible factor 1alpha (HIF-1alpha), vascular endothelial growth factor (VEGF), P-glycoprotein (P-gp), the production of which is regulated by HIF-1, and p53 proteins in their resected tumor by semiquantitative immunohistochemical analyses. Eight of 17 patients were treated with nitroglycerin patches before operation, but 9 of 17 patients were not. Furthermore, to study the relationship between changes in plasma VEGF levels by nitroglycerin treatment and response to DCb, 29 patients with advanced lung adenocarcinoma were treated with nitroglycerin for 3 days before chemotherapy using DCb. RESULTS: The rates of immunoreactive cells for HIF-1alpha, VEGF, and P-gp in tumor tissues treated with nitroglycerin were lower than those without nitroglycerin, but those for p53 were not different between those treated with and without nitroglycerin. Furthermore, the rates of immunoreactive cells for VEGF and P-gp proteins were significantly associated with those for HIF-1alpha in tumor tissue. The magnitude of decrease in plasma VEGF levels after treatment with nitroglycerin was significantly associated with response to DCb in patients with advanced lung adenocarcinoma. CONCLUSIONS: Nitroglycerin treatment may improve response to DCb in patients with lung adenocarcinoma, partly through decreasing VEGF and P-gp production via reduction of HIF-1alpha.  相似文献   
35.
Changes in cellular lipid metabolism are a common feature in most solid tumors, which occur already in early stages of the tumor progression. However, it remains unclear if the tumor‐specific lipid changes can be detected at the level of systemic lipid metabolism. The objective of this study was to perform comprehensive analysis of lipids in breast cancer patient serum samples. Lipidomic profiling using an established analytical platform was performed in two cohorts of breast cancer patients receiving neoadjuvant chemotherapy. The analyses were performed for 142 patients before and after neoadjuvant chemotherapy, and the results before chemotherapy were validated in an independent cohort of 194 patients. The analyses revealed that in general the tumor characteristics are not reflected in the serum samples. However, there was an association of specific triacylglycerols (TGs) in patients' response to chemotherapy. These TGs containing mainly oleic acid (C18:1) were found in lower levels in those patients showing pathologic complete response before receiving chemotherapy. Some of these TGs were also associated with estrogen receptor status and overall or disease‐free survival of the patients. The results suggest that the altered serum levels of oleic acid in breast cancer patients are associated with their response to chemotherapy.  相似文献   
36.
Certain features of pregnancy are important risk factors for breast cancer, such as protection afforded by young age at first birth. Preeclampsia, a pregnancy complication, is associated with reduced maternal breast cancer risk. However, questions remain regarding causality, biological mechanisms and the relation of other hypertensive conditions to risk. We conducted a population‐based case–control study of breast cancer cases (n = 116,196) in parous women identified through linkage of birth and cancer registries in Denmark, Finland, Norway and Sweden (1967–2013), including up to 10 matched controls per case (n = 1,147,192) sampled from the birth registries (complete data were not available on all variables). Odds ratios (ORs) with 95% confidence intervals (CIs) were derived from unconditional logistic regression models including matching factors (country, maternal birth year) and parity. Hypertension diagnosed before pregnancy (OR 0.87; 95% CI 0.78–0.97), gestational hypertension (OR 0.90; 95% CI 0.86–0.93) and preeclampsia (OR 0.91; 95% CI 0.88–0.95) were associated with reduced breast cancer risk. Results remained similar after adjustment for smoking and maternal body mass index before first pregnancy, and were generally similar stratified by parity, age at breast cancer diagnosis, time since first and last birth, sex of the offspring and calendar time. Except for retained placenta (OR 1.14; 95% CI 0.98–1.32), no other pregnancy complication appeared associated with breast cancer risk. The mechanisms mediating the modest risk reductions for history of preeclampsia or hypertension preceding or arising during pregnancy, and possible increased risk with history of retained placenta are unknown and warrant further laboratory, clinical and epidemiological investigation.  相似文献   
37.
Podoplanin (aggrus) is highly expressed in several types of cancers, including malignant pleural mesothelioma (MPM). Previously, we developed a rat anti‐human podoplanin mAb, NZ‐1, and a rat–human chimeric anti‐human podoplanin antibody, NZ‐8, derived from NZ‐1, which induced antibody‐dependent cellular cytotoxicity (ADCC) and complement‐dependent cytotoxicity against podoplanin‐positive MPM cell lines. In this study, we showed the antitumor effect of NZ‐1, NZ‐8, and NZ‐12, a novel rat–human chimeric anti‐human podoplanin antibody derived from NZ‐1, in an MPM orthotopic xenograft SCID mouse model. Treatment with NZ‐1 and rat NK (CD161a+) cells inhibited the growth of tumors and the production of pleural effusion in NCI‐H290/PDPN or NCI‐H226 orthotopic xenograft mouse models. NZ‐8 and human natural killer (NK) (CD56+) cells also inhibited tumor growth and pleural effusion in MPM orthotopic xenograft mice. Furthermore, NZ‐12 induced potent ADCC mediated by human MNC, compared with either NZ‐1 or NZ‐8. Antitumor effects were observed following treatment with NZ‐12 and human NK (CD56+) cells in MPM orthotopic xenograft mice. In addition, combined immunotherapy using the ADCC activity of NZ‐12 mediated by human NK (CD56+) cells with pemetrexed, led to enhanced antitumor effects in MPM orthotopic xenograft mice. These results strongly suggest that combination therapy with podoplanin‐targeting immunotherapy using both NZ‐12 and pemetrexed might provide an efficacious therapeutic strategy for the treatment of MPM.  相似文献   
38.
The prevalence of Neisseria gonorrhea (GC) and Chlamydia trachomatis (CT) is higher at extragenital anatomic sites among men who have sex with men (MSM) with HIV infection. Although national guidelines recommend that all MSM with HIV infection undergo screening for extragenital sexually transmitted infections (EG-STIs), uptake is low in many primary care settings. We evaluated EG-STI screening by primary care providers (PCPs) for US Air Force (USAF) members with incident HIV infection. All USAF members with incident HIV infection who received initial HIV specialty care with Infectious Disease (ID) providers at Brooke Army Medical Center from 2016 to 2018 (n = 98) were included. A retrospective chart review was conducted to evaluate STI screening performed by PCPs within 1 week of HIV diagnosis compared to screening at entry into ID care. Demographic, clinical, laboratory and behavioral risk data were collected. STI screening included GC/CT EG-STIs, urethral GC/CT, syphilis, and hepatitis B and C. Patients were predominantly male (98%) with a median age of 26 (IQR 23, 32) years at HIV diagnosis. A previous history of STIs was reported in 53 (54%) patients and the majority of males self-identified as MSM (66%) or bisexual (23%). The median time from HIV diagnosis to ID evaluation was 26 days (IQR 9, 33). PCPs performed any STI screening in 61 (62%) patients. EG-STI screening was conducted in 3 (3%) patients overall and in (3%) MSM/bisexuals. A total of 31 (32%) patients had missed STIs; the majority due to EG-STIs of the rectum (59%) and pharynx (19%). All EG-STIs would have been missed by urethral GC/CT screening alone. EG-STI screening uptake was low among PCPs evaluating USAF members with incident HIV infection. Underutilization of EG-STI screening can result in missed infections and forward transmission of GC/CT. Barriers to low uptake need to be explored.  相似文献   
39.
In recent years, there has been considerable research into functional materials inspired by living things. Much attention has been paid to the development of adhesive materials that mimic the adhesive proteins secreted by a mussel’s foot. These mussel-inspired materials have superior adhesiveness to various adherents owing to the non-covalent interactions of their polyphenolic moieties, e.g., hydrogen bonding, electrostatic interactions, and even hydrophobic interactions. Various factors significantly affect the adhesiveness of mussel-inspired polymers, such as the molecular weight, cross-linking density, and composition ratio of the components, as well as the chemical structure of the polyphenolic adhesive moieties, such as l-3,4-dihydroxyphenylalanine (l-Dopa). However, the contributions of the position and distribution of the adhesive moiety in mussel-inspired polymers are often underestimated. In the present study, we prepared a series of mussel-inspired alkyl methacrylate copolymers by controlling the position and distribution of the adhesive moiety, which are known as “forced gradient copolymers”. We used a newly designed gallic-acid-bearing methacrylate (GMA) as the polyphenolic adhesive moiety and copolymerized it with 2-ethylhexyl methacrylate (EHMA). The resulting forced gradient adhesive copolymer of GMA and EHMA (poly(GMA-co-EHMA), Poly1) was subjected to adhesion and dispersion tests with an aluminum substrate and a BaTiO3 nanoparticle in organic solvents, respectively. In particular, this study aims to clarify how the monomer position and distribution of the adhesive moiety in the mussel-inspired polymer affect its adhesion and dispersion behavior on a flat metal oxide surface and spherical inorganic oxide surfaces of several tens of nanometers in diameter, respectively. Here, forced gradient copolymer Poly1 consisted of a homopolymer moiety of EHMA (Poly3) and a random copolymer moiety of EHMA and GMA (Poly4). The composition ratio of GMA and the molecular weight were kept constant among the Poly1 series. Simultaneous control of the molecular lengths of Poly3 and Poly4 allowed us to discuss the effects on the distribution of GMA in Poly1. Poly1 exhibited apparent distribution dependency with regard to the adhesiveness and the dispersibility of BaTiO3. Poly1 showed the highest adhesion strength when the composition ratio of GMA was approximately 9 mol% in the portion of the Poly4 segment. In contrast, the block copolymer consisting of the Poly3 segment and Poly4 segment with only adhesive moiety 1 showed the lowest viscosity for dispersion of BaTiO3 nanoparticles. These results indicate that copolymers with mussel-inspired adhesive motifs require the proper design of the monomer position and distribution in Poly1 according to the shape and characteristics of the adherend to maximize their functionality. This research will facilitate the rational design of bio-inspired adhesive materials derived from plants that outperform natural materials, and it will eventually contribute to a sustainable circular economy.  相似文献   
40.
Background and hypothesisPsychotic disorders have been associated with not being in education, employment, and training (NEET). There is a lack of knowledge on the importance of risk markers for NEET among people with psychotic disorders and what rehabilitation they receive.Study designWe based our research on the register-based 1987 Finnish Birth Cohort study, which included all live births in Finland during that year. The study cohort were 288 people who had been diagnosed with psychotic disorders during 2004–2007, when they were 16–20 year old, and 55 883 who had not. We looked at the national register data for those subjects in 2008–2015, when they were 20–28 year old, and compared any associations between sociodemographic factors and NEET status.Study resultsNEET for more than 5 year affected 2.2% of those without psychosis, 35.8% of those with any nonaffective psychotic disorder, and 57.0% of those with schizophrenia or schizoaffective disorders. Family-related risk factors were weaker predictors of long-term NEET in subjects with psychotic disorders than other cohort members. Having a psychotic disorder plus long-term NEET was associated with not applying for upper secondary education, not finishing upper secondary education, parents receiving welfare benefits, being diagnosed with schizophrenia or schizoaffective disorders and being hospitalized for psychosis. Only 24.3% with psychotic disorders had participated in vocational rehabilitation.ConclusionsA diagnosis of psychosis in adolescence is independently associated with serious long term functional disability. Among those with psychotic disorders, educational problems are markers for adverse labor market outcomes. Despite this, vocational rehabilitation is seldom provided.  相似文献   
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