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1.
We analyzed DNA from 63 Japanese men with either azoospermiaor severe oligospermia whose Y chromosomes were cytogeneticallynormal. A total of 16 loci were examined: 15 loci on the longarm between DYS7E and DYZ1, and the YRRM1 locus, a candidategene for the azoospermic factor, AZF. One patient with a perlcentricinversion of the Y chromosome was also included. We detectedmicro-deletions in ten individuals. The YRRM1 gene was Involvedin only three of them. The remaining seven patients showed deletionbetween DYS7C and DYS239 in common, indicating the presenceof at least one additional gene, deletion of which causes azoospermia.  相似文献   
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Clinical and Experimental Nephrology - A growing body of evidence has shown that non-alcoholic fatty liver disease (NAFLD) is associated with chronic kidney disease (CKD). Non-invasive fibrosis...  相似文献   
3.
  1. We tested the hypothesis that activation of large conductance calcium-activated potassium channels is involved in dilator responses of the basilar artery to acetylcholine in vivo. Using a cranial window in anaesthetized rats, we examined responses of the basilar artery to acetylcholine.
  2. Topical application of acetylcholine (10−6 and 10−5M) increased diameter of the basilar artery from 238±7 μm to 268±7 and 288±7 μm, respectively (P<0.05 vs. baseline diameter). Iberiotoxin (10−8M), an inhibitor of large conductance calcium-activated potassium channels, did not affect baseline diameter of the basilar artery. In the presence of 10−8M iberiotoxin, 10−6 and 10−5M acetylcholine increased diameter of the basilar artery from 239±7 μm to 246±7 and 261±7 μm, respectively. Thus, iberiotoxin attenuated acetylcholine-induced dilatation of the basilar artery (P<0.05).
  3. Sodium nitroprusside (10−7 and 10−6M) increased diameter of the basilar artery from 242±9 μm to 310±12 and 374±13 μm, respectively (P<0.05 vs. baseline diameter). In the presence of iberiotoxin (10−8M), sodium nitroprusside (10−7 and 10−6M) increased diameter of the basilar artery from 243±6 μm to 259±9 and 311±12 μm, respectively. Thus, iberiotoxin attenuated dilator responses of the basilar artery to sodium nitroprusside (P<0.05).
  4. Iberiotoxin partly inhibited dilator responses of the basilar artery to forskolin, a direct activator of adenylate cyclase, but did not affect vasodilatation produced by levcromakalim, a potassium channel opener.
  5. These results suggest that dilator responses of the basilar artery to acetylcholine and sodium nitroprusside are mediated, in part, by activation of large conductance calcium-activated potassium channels. Because both acetylcholine and sodium nitroprusside have been shown to activate guanylate cyclase via nitric oxide, activation of large conductance calcium-activated potassium channels may be one of the major mechanisms by which cyclic GMP causes dilatation of the basilar artery in vivo.
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4.
We investigated influx and efflux transporters involved in blood-brain barrier transport of the nonsedative H1-antagonist epinastine. The basal-to-apical transport of [14C]epinastine was markedly higher than that in the opposite direction in LLC-GA5-COL150 cells stably transfected with human multidrug resistance (MDR)1 gene. The brain-to-plasma concentration ratio of [14C]epinastine in mdr1a/b(-/-) mice was 3.2 times higher than that in wild-type mice. The uptake of both [3H]mepyramine and [14C]epinastine into immortalized rat brain capillary endothelial cells (RBEC)1 showed temperature and concentration dependence. The kinetic parameters, K(m), V(max), and uptake clearance (V(max)/K(m)), of the initial uptake of [3H]mepyramine and [14C]epinastine by RBEC1 were 150 microM, 41.8 nmol/min/mg protein, and 279 microl/min/mg protein for mepyramine and 10.0 mM, 339 nmol/min/mg protein, and 33.9 microl/min/mg protein for epinastine, respectively. The uptake of [3H]mepyramine and [14C]epinastine by RBEC1 was inhibited by organic cations such as quinidine, amantadine, and verapamil, but not by other organic cations, tetraethyl ammonium, guanidine, and carnitine. Organic anions such as benzoic acid, estrone-3-sulfate, taurocholate, and neutral digoxin were not inhibitory. Furthermore, some cationic H1 antagonists (chlorpheniramine, cyproheptadine, ketotifen, and desloratadine) inhibited the [3H]mepyramine and [14C]epinastine uptake into RBEC1. In conclusion, the present study demonstrated that the combination of efficient efflux transport by P-glycoprotein and poor uptake by the influx transporter, which is identical with that responsible for the uptake of mepyramine, account for the low brain distribution of epinastine.  相似文献   
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7.
Nivolumab and pembrolizumab are humanized IgG4 monoclonal antibodies against programmed cell death 1 (PD-1). Although these agents are effective in treating advanced melanoma, non-small-cell lung carcinoma, and other types of cancers, various adverse events have been reported. Cutaneous adverse events are particularly prevalent and, while granulomatous/sarcoid-like reactions are uncommon, they are increasingly recognized as immune-related adverse events associated with immune checkpoint inhibitors. Herein, we report two cases of granulomatous/sarcoid-like reaction with foreign material, mimicking metastatic malignancy after PD-1 inhibitor treatment. Clinicians should be aware of the existence of cutaneous lesions and perform biopsy if needed to prevent misdiagnosis and unnecessary adjustments to immunotherapy.  相似文献   
8.
This randomized double-blind crossover study aimed to investigate the influence of cytochrome P450 (CYP) 2C19 polymorphisms on the antiplatelet effects of prasugrel in patients with non-cardioembolic stroke treated with clopidogrel. Patients received clopidogrel 75 mg/day for >?4 weeks. Subsequently, patients received prasugrel 3.75 mg/day (group A; n?=?64) or 2.5 mg/day (group B; n?=?65) for 4 weeks followed by a 4 week switched-dose regimen. To assess the influence of CYP2C19 polymorphisms, patients were classified as extensive metabolizers (EMs), intermediate metabolizers (IMs), and poor metabolizers (PMs). The primary endpoint was P2Y12 reaction units (PRU) at the end of each 4 week treatment. A significant reduction in PRU was noted after treatment with prasugrel 3.75 mg/day compared with the pre-dose value (after treatment with clopidogrel) (p?<?0.0001). By CYP2C19 phenotypes, a significant reduction in PRU was noted in IMs and PMs after treatment with prasugrel 3.75 mg/day and in PMs after treatment with prasugrel 2.5 mg/day, as compared with the pre-dose value (p?<?0.0001). The plasma concentration of the active metabolite of clopidogrel was relatively low in PMs compared to EMs and IMs; prasugrel was similar across all CYP2C19 phenotypes. No major or clinically significant hemorrhagic adverse events occurred. By CYP2C19 phenotype, the antiplatelet effects of prasugrel were greater with 3.75 mg/day in IMs and PMs, and with 2.5 mg/day in PMs compared with clopidogrel 75 mg/day, without safety concerns. CYP2C19 polymorphisms did not affect the plasma concentration of the active metabolite of prasugrel or its antiplatelet effects. (JapicCTI-101044).  相似文献   
9.
Rationale:In coronavirus disease 2019 (COVID-19) patients with acute respiratory distress syndrome refractory to optimal conventional management, we should consider the indication for veno-venous extracorporeal membrane oxygenation (V-V ECMO). Growing evidence indicates that COVID-19 frequently causes coagulopathy, presenting as hypercoagulation and incidental thrombosis. For these reasons, a multifactorial approach with several anticoagulant markers should be considered in the management of anticoagulation using heparin in COVID-19 patients on V-V ECMO.Patient concerns:A 48-year-old man was infected with COVID-19 with a worsening condition manifesting as acute respiratory distress syndrome.Diagnoses:He was refractory to conventional therapy, thus we decided to introduce V-V ECMO. We used heparin as an anticoagulant therapy for V-V ECMO and adjusted the doses of heparin by careful monitoring of the activated clotting time (ACT) and activated partial thromboplastin time (APTT) to avoid both hemorrhagic and thrombotic complications. We controlled the doses of heparin in the therapeutic ranges of ACT and APTT, but clinical hemorrhaging and profound elevation of coagulant marker became apparent.Interventions:Using thromboelastography (TEG; Haemonetics) in addition to ACT and APTT, we were able to clearly detect not only sufficient coagulability of COVID19 on V-V ECMO (citrated rapid thromboelastography-R 0.5 min, angle 75.5°, MA 64.0 mm, citrated functional fibrinogen-MA 20.7 mm) but also an excessive effect of heparin (citrated kaolin -R 42.7 min, citrated kaolin with heparinase 11.7 min).Outcomes:Given the TEG findings indicating an excessive heparin effect, the early withdrawal of ECMO was considered. After an evaluation of the patient''s respiratory capacity, withdrawal from V-V ECMO was achieved and then anticoagulation was stopped. The hemorrhagic complications and elevated thrombotic marker levels dramatically decreased.Lessons:TEG monitoring might be a useful option for managing anticoagulation in COVID-19 patients on V-V ECMO frequently showing a hypercoagulative state and requiring massive doses of heparin, to reduce both hemorrhagic and thrombotic complications.  相似文献   
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