Lack of evidence for an impairment of tuberoinfundibolar dopaminergic neurons in aged male rats of the Sprague-Dawley strain

Circulating prolactin (PRL) levels, dopamine (DA) content, in vitro basal and stimulus-evoked endogenous DA release from arcuate-periventricular nuclei median-eminence fragments were studied in young (4 months) and old (24-25 months) male rats of Sprague-Dawley strain. Serum PRL levels did not differ in young and aged animals. In addition DA tissue content, basal and K+- or d-amphetamine evoked endogenous DA release did not show age-related differences. These results suggest that in male rats of the Sprague-Dawley strain the activity of tuberoinfundibular dopaminergic (TIDA) neurons does not change during senescence, unlike what happens in other strains of rats.     

Macrophage-derived chemokine production by activated human T cells in vitro and in vivo: preferential association with the production of type 2 cytokines

Macrophage-derived chemokine (MDC), a potent chemoattractant for chronically activated Th2 lymphocytes, is constitutively expressed by dendritic cells, B cells, macrophages, and thymic medullary epithelial cells, whereas monocytes, NK cells, and T lymphocytes produce MDC only upon appropriate stimulation. In this study, we show in vitro MDC production also by activated T cells, which preferentially associate with the production of Th2 cytokines, IL-4, IL-5, and IL-6, and inversely correlate with the production of the Th1 cytokine, IFN-gamma. Moreover, high levels of MDC were detected in the sera of the great majority of subjects suffering from mycosis fungoides/Sézary syndrome or atopic dermatitis, which are considered as disorders characterized by the predominant expansion and activation of Th2 cells, respectively. By contrast, serum MDC levels in subjects with multiple sclerosis or Crohn's disease, which are characterized by a Th1 predominance, did not differ significantly from those of healthy controls. Finally, MDC expression was detected in the skin biopsy specimens of subjects with atopic dermatitis, where it was expressed by both dendritic cells and T lymphocytes. Taken together, these findings suggest that MDC production by activated T cells may occur both in vitro and in vivo, particularly in association with Th2 cytokines, thus providing an important amplification circuit for Th2-mediated responses.     

Endogenous dopamine release from tuberoinfundibular neurons: Does calmodulin play any role?

Summary The possible involvement of calmodulin in the process of endogenous dopamine (DA) release from arcuateperiventricular nuclei-median eminence fragments, containing tuberoinfundibular dopaminergic (TIDA) neurons, has been investigated in an in vitro incubation system. For this purpose the basal and K⁺-stimulated DA release was examined in the presence and in the absence of the different putative calmodulin antagonists, pimozide, trifluoperazine, penfluridol and N-(6-aminohexyl)-5-chloro-1-naphthalene-sulfonamide (W-7).Trifluoperazine and pimozide in concentrations up to 100 M were both uneffective in blocking K⁺-evoked DA release. Penfluridol in doses of 5 and 10 M, did not prevent 35 mM K⁺-induced endogenous DA release. It was able to reduce K⁺-stimulated DA release only at the very large concentration of 100 M.W-7 added in vitro to the hypothalamic fragments, prevented endogenous DA release evoked by 35 mM K⁺ in a dose-dependent manner. W-5, a chlorine deficient analogue of W-7, that interacts only weakly with calmodulin, failed to modify K⁺-stimulated endogenous DA release in doses up to 200 M.All the putative calmodulin antagonists used in the present study did not induce any change of basal DA release.IN conclusion the fact that most of the agents, except W-7, known to antagonize calmodulin-dependent processes in many biological systems failed to interfere with the release of endogenous DA from TIDA neurons seems to suggest that calmodulin does not play a crucial role in the process of DA release and that the inhibitory effect of W-7 on endogenous DA release may be better attributed to other mechanisms different from its anticalmodulin action.     

Remote intervention engagement and outcomes in the Clinical Trials in Organ Transplantation in Children consortium multisite trial

Remote interventions are increasingly used in transplant medicine but have rarely been rigorously evaluated. We investigated a remote intervention targeting immunosuppressant management in pediatric lung transplant recipients. Patients were recruited from a larger multisite trial if they had a Medication Level Variability Index (MLVI) ≥2.0, indicating worrisome tacrolimus level fluctuation. The manualized intervention included three weekly phone calls and regular follow-up calls. A comparison group included patients who met enrollment criteria after the subprotocol ended. Outcomes were defined before the intent-to-treat analysis. Feasibility was defined as ≥50% of participants completing the weekly calls. MLVI was compared pre- and 180 days postenrollment and between intervention and comparison groups. Of 18 eligible patients, 15 enrolled. Seven additional patients served as the comparison. Seventy-five percent of participants completed ≥3 weekly calls; average time on protocol was 257.7 days. Average intervention group MLVI was significantly lower (indicating improved blood level stability) at 180 days postenrollment (2.9 ± 1.29) compared with pre-enrollment (4.6 ± 2.10), p = .02. At 180 days, MLVI decreased by 1.6 points in the intervention group but increased by 0.6 in the comparison group (p = .054). Participants successfully engaged in a long-term remote intervention, and their medication blood levels stabilized. NCT02266888.     

Modulation of the K(+) channels encoded by the human ether-a-gogo-related gene-1 (hERG1) by nitric oxide

The inhibition of nitric oxide synthase by N-nitro-L-arginine methyl ester (0.03-3 mM) dose-dependently reduced nitric oxide (NO(*)) levels and enhanced the outward currents carried by human ether-a-gogo-related gene-1 (hERG1) K(+) channels expressed in Xenopus laevis oocytes, whereas the increase in NO(*) levels achieved by exposure to L-arginine (0.03-10 mM) inhibited these currents. Furthermore, four NO(*) donors belonging to such different chemical classes as sodium nitroprusside (1-1000 microM), 3-morpholino-sydnonimine (100-1000 microM), (Z)-1-[N-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1- ium-1, 2-diolate (NOC-18; 1-300 microM), and S-nitroso N-acetylpenicillamine (1-300 microM) dose-dependently inhibited hERG1 outward K(+) currents. By contrast, the NO(*) donor NOC-18 (0.3 mM) did not affect other cloned K(+) channels such as rat neuroblastoma-glioma K(+) channel 2, rat delayed rectifier K(+) channel 1, bovine ether-a-gogo gene, rat ether-a-gogo-related gene-2, and rat ether-a-gogo-related gene-3. The inhibitory effect of NO(*) donors on hERG1 K(+) channels was prevented by the NO(*) scavengers 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide and hemoglobin. The membrane permeable analog of cGMP, 8-bromo-cGMP (1 mM), failed to reproduce the inhibitory action of NO(*) donors on hERG1 outward currents; furthermore, the specific inhibitor of the NO(*)-dependent guanylyl cyclase, 1H-[1,2,4]oxadiazolo[4, 3-a]quinoxalin-1-one (50 microM), neither interfered with outward hERG1 K(+) currents nor prevented their inhibition by 0.3 mM NOC-18. Both L-arginine (10 mM) and NOC-18 (0.3 mM) counteracted the stimulatory effect on hERG1 outward currents induced by the radical oxygen species-generating system FeSO(4) (25 microM)/ascorbic acid (50 microM; Fe/Asc). Finally, L-arginine (10 mM) and NOC-18 (0.3 mM) inhibited both basal and Fe/Asc (0.1 mM/0.2 mM)-stimulated lipid peroxidation in X. laevis oocytes. Collectively, the present results suggest that NO(*), both endogenously produced and pharmacologically delivered, may exert in a cGMP-independent way an inhibitory effect on hERG1 outward K(+) currents via an interaction with radical oxygen species either generated under resting conditions or triggered by Fe/Asc.     

Total Joint Arthroplasty: Trends in Medicare Reimbursement and Implant Prices

Total joint arthroplasty (TJA) continues to be a popular target of cost control efforts. In order to provide a unique overview of financial trends facing TJA, we analyzed Medicare databases including 100% of beneficiaries, as well as industry surveys of implant list prices. Although there was a substantial increase in TJA utilization over the period 2000–2011 (+ 26.9%), growth has been stagnant since 2005. New coding schemes have made complicated cases more lucrative for hospitals (+ 2.5% to 6.5% per year), while reimbursements for uncomplicated cases have fallen (− 0.7% to − 0.6%). Physician reimbursements have declined on all case types (− 2.5% to − 2.1% per year), while list prices of orthopedic implants have risen (+ 4.8% to 5.5%). These trends should be kept in mind while contemplating future changes to TJA payment.     

TSH/cAMP up-regulate sarco/endoplasmic reticulum Ca2+-ATPases expression and activity in PC Cl3 thyroid cells

OBJECTIVE: We recently reported that the sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) 2b is the SERCA form preferentially expressed in rat thyroid. Moreover, SERCA2b expression dramatically decreases in virally transformed, highly tumorigenic, PC Cl3 thyroid cells. These results suggest that, in the thyroid, SERCA2b, in addition to its housekeeping role, is linked to differentiation and is a regulated gene. We therefore sought to study the effect of TSH, the main regulator of thyroid function, on SERCA2b expression and activity. METHODS: PC Cl3 cells were hormone starved in low-serum medium and stimulated for long (48 h) or short (1, 2 and 4 h) times. SERCA2b expression and activity were evaluated by Northern and Western blots, Ca2+-ATPase activity and Ca2+ store content. RESULTS: In PC Cl3 cells, SERCA2b mRNA and protein were induced twofold by a 48-h long treatment with TSH. Long-term elevation (48 h) of intracellular cAMP levels, by forskolin or 8-Br-cAMP, had similar effects on SERCA2b mRNA and protein. We also measured Ca2+-ATPase activity and Ca2+ store content. Both long (48 h) and short (0.5-1 h) treatments with TSH, forskolin or 8-Br-cAMP induced a marked increase of SERCA2b activity. This effect was completely abolished by H89, a specific inhibitor of cAMP-dependent protein kinase A (PKA). TSH and 8-Br-cAMP increased Ca2+ store content after both long (48 h) and short (1-2 h) treatments. CONCLUSIONS: These data suggested that TSH/cAMP acts as an important regulator of both SERCA2b expression and activity in the thyroid system, through PKA activation.