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Introduction As Chimeric Antigen Receptor T-cell (CAR-T) therapy gains its clinical advantage in the management of diffuse large B cell lymphoma (DLBCL), accumulating evidence shows that it often accompanies cardiac dysfunction. Previous retrospective studies indicated the potential involvement of cytokine release syndrome (CRS) in cardiac dysfunction after CAR-T therapy, but no prospective study has reported the time course of cardiac dysfunction. Moreover, the relationship between the severity of CRS and cardiac dysfunction after CAR-T therapy remains unclear. Purpose The objectives of this study are to prospectively examine the sequential changes in cardiac markers overtime after CAR-T therapy and to clarify the association between the grade of CRS and cardiac markers. Methods In this prospective observational study, 30 DLBCL patients who underwent CAR-T therapy from July 2020 to March 2022 were enrolled. Before and after the treatment, the level of cardiac biomarkers and echocardiographic index were sequentially collected. We classified all patients into two groups according to the severity of CRS after CAR-T therapy, namely low-CRS group (CRS Results The average age of participants was 59.6 years, and 9 patients (30%) were female. The average duration of DLBCL was 2.7 years. The CRS showed its peak severity on day 3. The number of patients in low- and high-CRS group was 13 and 17, respectively and tocilizumab was administrated for 46% and 71% of the patients in low- and high-CRS group, respectively. At the baseline before CAR-T therapy, there were no significant differences in cardiac parameters between the two groups. During the follow-up, sequential measurements of cardiac biomarkers revealed that high-CRS group showed significantly higher NT-proBNP level compared to that of low-CRS group (NT-proBNP; 90pg/ml vs. 623pg/ml, p=0.0001, respectively) and both had their peak on day 3, whereas troponin T level did not show any differences. Likewise, sequential measurements of echocardiographic parameters revealed that high-CRS group showed significantly increased E/A compared to low-CRS group on day 7 (E/A; 0.77 vs. 0.90, p=0.021, respectively), but not in the later phase. The parameters for systolic function including GLS and EF and parameters for diastolic function such as E/e' and LAVI did not alter among the two groups throughout the follow-up. Conclusion In the patients who underwent CAR-T therapy for DLBCL, the elevation of NT-proBNP level and increase in E/A was transiently observed within a week and correlated with the severity of CRS. Funding Acknowledgement Type of funding sources: None.

Importance: Sodium glucose cotransporter 2 inhibitors reduce morbidity and mortality in patients with heart failure and reduced ejection fraction (HFrEF). Clinicians may find estimates of the projected long-term benefits of sodium glucose cotransporter 2 inhibitors a helpful addition to clinical trial results when communicating the benefits of this class of drug to patients. Objective: To estimate the projected long-term treatment effects of dapagliflozin in patients with HFrEF over the duration of a patient’s lifetime. Design, Setting, and Participants: Exploratory analysis was performed of Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure (DAPA-HF), a phase 3 randomized, placebo-controlled clinical trial conducted at 410 sites in 20 countries. Patients with an ejection fraction less than or equal to 40% in New York Heart Association functional classification II to IV and elevated plasma levels of N-terminal pro B-type natriuretic peptide were enrolled between February 15, 2017, and August 17, 2018, with final follow-up on June 6, 2019. Mean (SD) duration of follow-up was 17.6 (5.2) months. Interventions: Dapagliflozin, 10 mg, once daily vs placebo in addition to standard therapy. Main Outcomes and Measures: The primary composite outcome was time to first hospitalization for heart failure, urgent heart failure visit requiring intravenous therapy, or cardiovascular death. The trial results were extrapolated to estimate the projected long-term treatment effects of dapagliflozin over the duration of a patient’s lifetime for the primary outcome and the secondary outcome of death from any cause. Results: A total of 4744 patients (1109 women [23.4%]; 3635 men [76.6%]) were randomized in DAPA-HF, with a mean (SD) age of 66.3 (10.9) years. The extrapolated mean event-free survival for an individual aged 65 years from a primary composite end point event was 6.2 years for placebo and 8.3 years for dapagliflozin, representing an event-free survival time gain of 2.1 years (95% CI, 0.8-3.3 years; P = .002). When considering death from any cause, mean extrapolated life expectancy for an individual aged 65 years was 9.1 years for placebo and 10.8 years for dapagliflozin, with a gain in survival of 1.7 years (95% CI, 0.1-3.3; P = .03) with dapagliflozin. Similar results were seen when extrapolated across the age range studied. In analyses of subgroups of patients in DAPA-HF, consistent benefits were seen with dapagliflozin on both event-free and overall survival. Conclusions and Relevance: These findings indicate that dapagliflozin provides clinically meaningful gains in extrapolated event-free and overall survival. These findings may be helpful in communicating the benefits of this treatment to patients with HFrEF. Trial registration: ClinicalTrials.gov Identifier: NCT03036124.

Background Left ventricular (LV) systolic dysfunction and heart failure (HF) in patients with lower extremity artery disease (LEAD) is associated with an increased risk for adverse events. However, relationship between long-term outcome in patient with LEAD and LV diastolic dysfunction remains unclear. Purpose The aim of this study was to assess the impact of LV diastolic dysfunction on long-term outcome in patients with LEAD. Methods Two hundred patients (male 66%, mean age 76±9 years) with preserved LV systolic function assessed by echocardiography (ejection fraction ≥50%) were enrolled from a single-center database between January 2013 to May 2015. Baseline LEAD was identified by ABI Results LV diastolic dysfunction was identified in 31%. The mean observation period was 32±21 months. The primary endpoint occurred more frequently in patients with LV diastolic dysfunction than those without at 3 years (30% vs 16%, P=0.02). There were no significant differences between 2 groups in the myocardial infarction (3% vs 3%, P=0.73) and stroke (3% vs 3%, P=0.55). Cardiovascular death (19% vs 7%, P=0.01) and hospitalization for HF (19% vs 7%, P=0.01) were significantly higher in patients with LV diastolic dysfunction. In multivariate analysis, LV diastolic dysfunction was an independent predictor for primary endpoint (HR=2.28, 95% CI 1.10–4.73, P=0.02) (Table) Predictor for primary endpoint Factors Univariate model Multivariate model Hazard ratio [95% CI] P value Hazard ratio [95% CI] P value Age 1.03 [0.98–1.08] 0.24 1.03 [0.98–1.08] 0.22 Chronic kidney disease 1.53 [0.77–3.07] 0.23 1.25 [0.60–2.58] 0.55 Coronary artery disease 1.08 [0.53–2.18] 0.84 1.18 [0.56–2.50] 0.65 Cerebrovascular disease 1.93 [0.74–5.02] 0.17 2.28 [0.86–6.05] 0.10 Critical limb ischemia 3.75 [1.68–8.37] Conclusions LV diastolic dysfunction increased the risk for adverse events in patients with LEAD. Acknowledgement/Funding None

Thiopurines (azathioprine and 6-mercaptopurine) can induce life-threatening myelosuppression. This study determined the frequency, timing, and outcomes of mild and severe myelosuppression after initiation of thiopurine therapy.This retrospective cohort study included patients with inflammatory bowel disease who were new users of thiopurines; those tested for thiopurine methyltransferase levels before therapy were excluded. Patients were followed from their first thiopurine prescription until the earliest of severe leukopenia (white blood cell count,1.0 x 10(9)/L), severe thrombocytopenia (platelet level,20 x 10(9)/L), the end of therapy, the first gap in therapy, disenrollment, or December 31, 2006.Among 1997 new users, the incidence of severe leukopenia per 100 person-months was 0.16 (95% confidence interval [CI], 0.03-0.29; n = 6) in weeks 0 to 8, 0.00 in weeks 9 to 24, and 0.01 (95% CI, 0-0.03; n = 3) after week 26 of therapy. The incidence of severe neutropenia and severe thrombocytopenia per 100 person-months during the first 8 weeks of therapy was 0.51 (95% CI, 0.31-0.80; n = 19) and 0.08 (95% CI, 0.02-0.23; n = 3), respectively. During the first 8 weeks, the median duration from a normal white blood cell count to severe leukopenia was 13 days (range, 8-26 d) and to severe neutropenia was 14 days (range, 7-23 d).The high incidence of severe myelosuppression justifies frequent monitoring during the first 8 weeks of therapy. Subsequently, the rate of severe myelosuppression and the proportion of patients who progress from mild to severe myelosuppression decrease, justifying less-frequent monitoring.

Licorice flavonoid oil (LFO) is a new functional food ingredient. In this study, the genotoxicity of LFO was investigated using a test battery of three different methods. In a reverse mutation assay using four Salmonella typhimurium strains and Escherichia coli, LFO did not increase the number of revertant colonies in any tester strain with or without metabolic activation by rat liver S9 mix. In a chromosomal aberration test using Chinese hamster lung (CHL/IU) cells, LFO did not induce any chromosomal aberrations either in the short period test without rat liver S9 mix or in the continuous treatment (24 h or 48 h) test. However, in the short-period test with rat liver S9 mix, LFO induced structural chromosomal aberrations at concentrations higher than 0.6 mg/mL. A bone marrow micronucleus test using male F344 rats was initially conducted. The animals were dosed by oral gavage at doses up to 5000 mg/kg/day. No significant or dose-dependent increases in the frequency of micronucleated polychromatic erythrocytes (MNPCE) were observed and the high dose suppressed the ratio of polychromatic erythrocytes (PCE) to total erythrocytes. Subsequently, a liver and peripheral blood micronucleus test using male F344 rats was conducted. No micronuclei induction either in hepatocytes or PCE was observed even at the highest dose of 5000 mg/kg/day. From the findings obtained from the genotoxicity assays performed in this study and the published pharmacokinetic studies of LFO, it appears unlikely that dietary consumption of LFO will present any genotoxic hazard to humans.

A digital anemometer is presented for air flow measurements in house and office environments. The principle is based on hot-wire anemometry. The probe consists of a cold thermistor for flow temperature detection and a hot thermistor for flow velocity detection. The latter is self-heated by a thermal bridge. Its imbalance voltage due to the air flow is compared with the reference response transformed to the time domain by direct digital synthesizing. This pulse-width modulation provides the linear digital representation of the flow velocity under measurement. The imbalance component due to flow temperature is compensated for by scaling the reference response depending on temperature detected by a cold thermistor. These linearization and compensation techniques make accurate measurements possible with a simple configuration. The performance of a prototype anemometer built using a one-chip 4-b microcomputer is also presented to demonstrate the validity of these techniques. >

To develop an effective multiplex PCR for simultaneous and rapid detection of Vibrio cholerae, Vibrio vulnificus and Vibrio parahaemolyticus, the three most important Vibrio species that can cause devastating health hazards among human.Species-specific PCR primers were designed based on toxR gene for V. cholerae and V. parahaemolyticus, and vvhA gene for V. vulnificus. The multiplex PCR was validated with 488 Vibrio strains including 322 V. cholerae, 12 V. vulnificus, and 82 V. parahaemolyticus, 20 other Vibrio species and 17 other bacterial species associated with human diseases. It could detect the three target bacteria without any ambiguity even among closely related species. It showed good efficiency in detection of co-existing target species in the same sample. The detection limit of all the target species was ten cells per PCR tube.Specificity and sensitivity of the multiplex PCR is 100% each and sufficient for simultaneous detection of these potentially pathogenic Vibrio species in clinical and environmental samples.This simple, rapid and cost-effective method can be applicable in a prediction system to prevent disease outbreak by these Vibrio species and can be considered as an effective tool for both epidemiologist and ecologist.

Using stoichiometric hydrogen-oxygen and propane-oxygen mixtures, the detonation was made spherically converge toward the center of the detonation chamber, whose cross section was made conical. The scratch was observed at the center. The depth and the width of the deepest point of the scratch were twenty and several μm and 0.1 mm, respectively.

High-density optical storage systems, utilizing a violet laser diode and high NA (numerical aperture) objective lens, are being developed by various companies. Consequently, a need has arisen for improved focus servo capturing, i.e. transition from seeking to servo lock. This is due to the improvement in the sensitivity of focus sensor optics at the expense of its linear range. Also, the small working distance of the high NA objective lens has increased the risk of collision. A DVD focus servo system is shown in Fig. 1. A focus error signal is detected to be S-shaped as shown in Fig.2, and has limited linear range that can be used to servo. When the relative deviation exceeds a certain limit, some form of insurance measure must be adopted, such as brakes, to put the lens back into the linear region. The relative velocity at which the servo loop can settle decreases according to the decrease in linear range. So high-speed servo capturing is more difficult in high-density optical storage systems than in conventional DVD. In this paper, we propose two approaches to improve the performance of servo capturing. One approach is a scheme to optimize the initial states of the controller, and another is a scheme to estimate the relative position between the objective lens and disk by introducing a model of the system.

Thin film of (Ba/sub 0.75/Sr/sub 0.25/)TiO/sub 3/ with equivalent SiO/sub 2/ thickness of 0.47 nm has been developed for capacitor dielectric film of 256 Mbit DRAM. A novel cell design named FOGOS (FOlded Global and Open Segment bit-line cell) structure is also proposed for 256 Mbit DRAM. By combining high dielectric constant film and FOGOS design, we have succeeded in making a practical and integrated cell that has sufficient cell capacitance with planar stacked capacitor, small bitline parasitic capacitance and large lithographic tolerance of alignment and DOF. 0.72 /spl mu/m/sup 2/ cell size based on 0.25 /spl mu/m process technology is realized. >

A digital anemometer using a self-heated thermistor as a probe has been developed for low flow rate measurements. The principle of measurement is based on hot-wire anemometry. To enhance the probe sensitivity to the flow rate while reducing the convection due to self-heating to a minimum, the thermistor is kept to the lowest possible temperature for exhibiting the negative resistance. The heat removed from the thermistor is analyzed and compared with the measured results, to derive the characteristic function which relates the voltage across the thermistor to the flow rate and temperature. This function is transformed from the flow rate domain to the time domain by the digital waveform synthesis. The carrier signal thus generated is pulse-width-modulated by the output of the probe, to provide the digital representation of the flow rate under measurement. The cross-sensitivity of the probe to the fluid temperature is compensated by scaling the carrier amplitude. Exempting linearization and compensation for the convection, this process of quantization makes a high accuracy flow rate measurement possible with a simple configuration. >

A digital hygrometer using a relative humidity sensor is developed. The sensor consists of a polyimide film spin-coated onto a Si substrate. The sensor model for signal processing is first derived which describes the sensor capacitance in terms of relative humidity and temperature in closed form. The interface appropriate for the sensor model is next designed based on a relaxation oscillator. A prototype hygrometer built using a one-chip microcomputer for signal processing and its performance are finally described to demonstrate the validity of the sensor model and interface

To clarify the healing process of disrupted culprit plaques of acute myocardial infarction (MI), we serially observed the culprit plaques for 18 months after the onset of acute MI by angioscopy.Although it has been reported that disruption of the yellow plaque and subsequent thrombosis cause acute MI and that the thrombogenicity of the plaque lasts for a month, the healing process of the plaque after disruption has not been clarified.Eighty-five patients with acute MI were prospectively and consecutively enrolled. Angioscopic studies were performed immediately and at 1, 6 and 18 months after successful reperfusion. The prevalence of yellow plaques and thrombus was examined. The color grade of the plaque was determined as 0 (white), 1 (light yellow), 2 (yellow) or 3 (bright yellow).Although yellow plaque was present at the culprit lesion in most patients throughout follow-up, its color grade was reduced from one to six months (1.9 +/- 0.6 vs. 1.1 +/- 0.7, p = 0.0003) after reperfusion, especially in the patients without hyperlipidemia (HL). The incidence of thrombus was 92.5% immediately after reperfusion, which was reduced significantly to 63.8%, 4.8% and 11.8% at 1, 6 and 18 months, respectively. The incidence of thrombus (77.8% vs. 45.0%, p = 0.03) at one month was higher in the patients with diabetes mellitus (DM).The healing process of yellow plaques at the culprit lesions of MI was detected by angioscopy as reductions of color grade and thrombogenicity at six months and partially at one month after the onset of acute MI. This healing process appears to deteriorate by complicating cases of DM or HL.

Amlodipine increases NO levels in coronary vessels and aorta via bradykinin-dependent mechanisms in vitro. We have previously reported that a long-acting Ca channel blocker, benidipine, increases cardiac NO levels in ischemic canine hearts, suggesting that benidipine may also protect against ischemia and reperfusion injury via bradykinin- and NO-dependent mechanisms. We examined this possibility. In open chest dogs, the left anterior descending coronary artery was perfused with blood through a bypass tube and was occluded for 90 min followed by 6 hours of reperfusion. Infarct size was assessed by TTC staining at 6 hours of reperfusion. When benidipine doses of 50, 100, and 200 ng/kg/min were infused via the bypass tube between 10 min prior to the onset of ischemia and after 60 min of reperfusion, systemic blood pressure did not change significantly. Infarct size decreased with the administration of benidipine (50, 100, and 200 ng/kg/min) when compared to the untreated condition (24.8+/-2.5, 17.3+/-3.1, and 16.5+/-2.0 vs. 43.4+/-5.6%, respectively) associated with the increased release of NO and bradykinin in the coronary venous blood upon reperfusion. Myeloperoxidase activity of the myocardium increased after 6 hours of reperfusion, which was attenuated by benidipine. The limitation of infarct size and the increase in myeloperoxidase activity were completely blunted by either L-NAME or HOE140. There were no significant differences in collateral blood flow assessed by the microsphere method after 45 min of ischemia for any of the groups. Thus, we conclude that the Ca channel blocker, benidipine, limits infarct size via bradykinin- and NO-dependent mechanisms.

Although cDNA array technique has recently become available in the cardiovascular field, it has not yet been established what kind of genes in the myocardium are expressed by acute ischemia. Since many substances contribute to the pathophysiology of acute ischemic hearts, we investigated transcription responses of murine hearts to ischemia using cDNA array representing 18,376 genes.In 29 male mice, we ligated the proximal site of the left coronary artery for 60 min. In 14 mice, we performed the sham operation without the ligation of the left coronary artery. After 60 min, the hearts were excised to obtain mRNA, and we performed cDNA array analysis. In 18,376 cDNA, 2 known genes were upregulated over 10-fold, 11 known genes were upregulated 5.0- to 9.9-fold, and 32 unknown genes were upregulated over 5.0-fold compared to sham-operated controls. In contrast, 11 known genes and 7 unknown genes were downregulated to levels below 0.2-fold. For 9 of the 13 known genes of which expression was increased as analyzed by cDNA array, subsequent Northern blot analysis also revealed an increase in expression.Using cDNA array analysis we found that cardiac expression of 24 known and 39 unknown genes was modulated by acute ischemic stress, and appeared to be related to the pathophysiology of ischemic hearts. These results show that cDNA array analysis may provide a new molecular insight to the pathophysiology of acute ischemic hearts.

Chronic mild or moderate stress elicits an adaptive change in central nervous systems that function to maintain homeostasis. The principal components of stress response are the extrahypothalamic corticotropin-releasing hormone (CRH) and the locus coeruleus (LC)-norepinephrine (NE) systems. CRH is known to produce various stress-, anxiety- and arousal-associated behaviors in animals. Moreover, CRH causes an increase in the firing rate and activity of tyrosine hydroxylase in the LC, and NE release in LC projection areas. It is thought that chronic inescapable and unpredictable stress can result in a sustained dysregulation of both CRH neuronal activity and LC-NE systems. One may hypothesize that the NE-CRH interaction occurs in the terminal projection of forebrain NE systems, the hypothalamic paraventricular nucleus (PVN), the bed nucleus of the stria terminalis (BNST) and the central nucleus of the amygdala (CeA) where NE stimulates CRH release. Such CRH-NE-CRH feed-forward systems elicit progressive augmentation of stress responsivity with repeated exposure. The beta-adrenergic receptor down-regulation is induced by acute and chronic exposure to moderate and predictable stress, implying an adaptation to stress. However, chronic unpredictable (variable) stress (CVS), a model for depression, up-regulated the beta-AR. In our laboratory, we found that concurrent treatment with the selective serotonin reuptake inhibitor (SSRI) citalopram caused beta-R down-regulation in the frontal cortex of rats treated with CVS for 14 days. As previously reported by the authors, an increase in 5-HT availability plays a role in preserving beta-R down-regulation by NE potentiating agents. In depressed patients, hyperactivation of the CRH-NE systems caused by the CRH-NE feed-forward system is thought to be involved in generating anxiety, sympathetic activation and hyperarousal. Moreover, a decrease in the 5-HT turnover in depressed patients has been reported. Accordingly, it is proposed that an increase in 5-HT availability by SSRI might contribute to normalize beta-R down-regulation as an adaptive regulatory mechanism against excessive CRH-NE neurotransmission under a "stressful" situation.

We evaluated the effect of epidural blood patch (EBP) in the treatment of two cases of spontaneous intracranial hypotension (SIH). Both case 1 (53-year old female) and case 2 (44-year old female) had severe postural headache and showed meningeal thickening by cranial MRI, and were diagnosed as SIH. Case 1: Although her intracranial pressure remained within normal ranges, an extradural leakage was shown in the middle thoracic region on isotope cisternography using indium-111 labeled DTPA. She underwent epidural blood patch with autologous blood at Th 6-7 level twice (10 ml and 15 ml, respectively) but without remarkable pain relief. Case 2: Her intracranial pressure was low (0 mmH2O on supine position), but, isotope cisternography using DTPA showed only the early appearance of isotope in the bladder but failed to disclose the site of the CSF leak. Epidural blood patch with 30 ml of autologous blood was performed at Th 12-L 1 level which only resulted in severe backache without clinical improvement. In conclusion, we could not find the effectiveness of EBP on the two cases of SIH, although there are many reports on its efficacy.

Dysregulation in the negative feedback of the hypothalamus-pituitary-adrenal (HPA) system is observed in a subgroup of major depression. Recent studies have postulated that tricyclic antidepressant treatment increases the glucocorticoid receptor (GR) in the brain and that such GR up-regulation normalizes the hyperactivity of HPA systems. The GR is associated with heat-shock proteins (HSPs) as a functional complex with a high affinity for steroid binding. In this study, we have examined the effects of chronic fixed (restraint) stress (CFS) and chronic variable stress (CVS) on the subcellular localization of GR and HSP90 in rat hippocampus using an immunoblotting procedure. A single restraint stress for 1-2 h and a single treatment with dexamethasone (DEX) 0.5 mg/kg, s.c. induced a translocation of the cytosolic GR to nuclei. Long-term treatment with DEX 0.1 mg/kg, s.c. for 14 days caused a significant decrease in both cytosolic and nucleic GR. There was no significant change in either cytosolic or nucleic GR after CFS for 14 days. However, CVS for 14 days increased both cytosolic GRs and HSP90 while nucleic GR was not changed. CFS for 14 days had no influence on the DEX-induced translocation of GR to nuclei, whereas GR translocation by DEX was not observed after CVS for 14 days. Gel filtration chromatography of the hippocampal cytosol after CVS indicated an increase in monomeric GR (approximately 90 kDa) and a decrease in the GR-HSP complex (approximately 300 kDa). Since CVS has been reported to increase serum corticosterone in rats, our results suggest that CVS prevents formation of the GR-HSP complex. A new intracellular environment rather than excessive serum corticosterone caused by CVS may contribute to inhibition of the formation of GR-HSP complex. It is proposed that the CVS could be an appropriate model for disturbance in the negative feedback control of HPA systems.

Although antidepressants are currently in widespread use as psychotropic drugs, their precise mechanism of action has not yet been elucidated. The strong potency of antidepressants for inhibiting the reuptake of catecholamines into presynaptic nerve terminals was initially the basis for Schildkraut’s proposal of the monoaminergic hypothesis of affective disorders (Schildkraut 1965). This hypothesis should be extended or revised, as the inhibition of catecholamine reuptake is observed within minutes to hours after administration of a single antidepressant, whereas the clinical effect in depressive patients is often seen only after 1 to 3 weeks of daily treatment. Vetulani and Sulser (1975) proposed that this delay in the occurrence of the therapeutic action could be correlated with the development of noradrenergic subsensitivity of the cyclic adenosine monophosphate (cAMP) generating system in the brain after chronic, but not acute, treatment with tricyclic antidepressants and with some atypical antidepressants.

Histamine H1-receptor occupancy in the human brain was measured in healthy young volunteers by positron emission tomography (PET) using [11C]doxepin. d-Chlorpheniramine, a selective and classical antihistamine, occupied 76.8 +/- 4.2% of the averaged values of available histamine H1 receptors in the frontal cortex after its administration in a single oral dose of 2 mg. Epinastine, a non-sedative antihistamine, occupied 13.2 +/- 18.5% of the available H1 receptors in the human frontal cortex after its administration in a single oral dose of 20 mg. There was significant correlation between H1 receptor occupancy by epinastine and its plasma concentration in each subject. PET data on the human brain were essentially compatible with those on H1-receptor occupancy in the guinea pig brain as determined by an in vivo binding technique, although for the same H1-receptor occupancy, the dose was less in humans than in guinea pigs. Our PET studies demonstrated that receptor occupancy by a second-generation H1 antagonist, epinastine, was less than 20% of the total H1 receptors, and that the low receptor occupancy was closely related to the low incidence of central side effects.

We examined the effects of chronic treatment with several types of antidepressants on microtubule assembly and phosphorylation of microtubule-associated proteins (MAPs) in the rat cerebral cortex. The microtubule assembly was monitored in turbidity at 350 nm using a spectrophotometer. Chronic but not acute treatment with desipramine (DMI), maprotiline (MPR) or citalopram (CTR) inhibited microtubule assembly, assayed in the presence of protein phosphatase inhibitors (PPI). In contrast, this inhibitory effect was completely nullified in the absence of PPI. The three compounds had no direct effect on microtubule assembly. The phosphorylation of MAPs (MAP2 and tau) was investigated by immunoblotting with monoclonal antibodies (phosphoserine, phosphothreonine and phosphotyrosine) after immunoprecipitation of MAPs. The serine but not threonine or tyrosine phosphorylation of MAP2 was significantly increased after chronic treatment with DMI, MPR or CTR. The phosphorylation of tau was not altered following chronic administration of antidepressants. These results suggest that the inhibition of microtubule assembly observed after chronic antidepressant treatment is attributable to an increase in the phosphorylated MAP2 and this effect may represent a novel and common action of typical and atypical antidepressant agents. Our results show that besides second messengers system, protein phosphorylation might be involved in the therapeutic effects of antidepressants.

Tolerance to catecholamines in the beta-adrenergic and dopaminergic receptor-adenylate cyclase system from the rat prostatic membrane has been studied. Preincubation of the tissue with isoproterenol produced not only a decrease in beta-adrenergic receptors and its sensitive adenylate cyclase activity, but also a reduction in dopaminergic response. Similarly, exposure to dopamine resulted in a decline both of isoproterenol- and dopamine-stimulated adenylate cyclase activity. A beta adrenergic antagonist, propranolol, exclusively blocked desensitization in the beta-adrenergic and dopaminergic adenylate cyclase system caused by isoproterenol, while dopamine-induced refractoriness was prevented by a dopaminergic antagonist, haloperidol. These results suggest that desensitization of the beta-adrenergic and dopaminergic adenylate cyclase system begins on receptor-occupation by its specific agonist.

By administering fluorescein intravenously to 95 patients we calculated the ratio of fluorescein concentration in the vitreous at the time of its peak level compared with the estimated unbound concentration of fluorescein in the plasma at the same time. We studied 12 normal phakic and 83 aphakic eye approximately two months, one year, and more than two years after cataract extraction. All the eyes had undergone intracapsular cataract extraction or extracapsular cataract extraction, with or without posterior capsulotomy, because of senile cataract. The calculated ratio in patients with intracapsular and extracapsular lens extraction was statistically significantly reduced at two months and one year after cataract extraction and was normalised at more than two years after the operation in comparison with normal subjects. The ratio was statistically extracapsular extraction at two months and one year after surgery. Posterior capsulotomy had no effect on the ratio. The ratio, we considered, at least partially reflects the outward transport of fluorescein from the vitreous cavity. Although the findings reflect subclinical phenomena, they are of importance when considering postoperative sequelae. The posterior lens capsule, zonule, and intact anterior vitreous face may be essential for the anterior uvea to function in the outward transport of fluorescein from the vitreous cavity.

The role of serotonin (5-HT) and protein kinases in the regulation of the beta-receptor induced by typical and atypical antidepressants was investigated. Treatment with either mianserin or maprotiline for seven days produced a significant decrease in the beta-receptor density measured 6h after the last dose. The reduction in beta-receptors disappeared within 24h. However, combined treatment of mianserin or maprotiline with either fluoxetine or 5-hydroxytryptophan significantly decreased beta-receptors even 24h after the last dose. Following treatment with p-chlorophenylalanine the reduction in beta-receptors induced by desipramine was reversible within 24h. These results demonstrate that an increase in the synaptic 5-HT availability may contribute to the prolongation of the beta-receptor down-regulation by antidepressants. The intraventricular infusion of 12-0-tetradecanoyl-phorbol-13-acetate (TPA), a potent protein kinase C (PK-C) activator for seven days caused a significant decrease in beta-receptors, while forskolin or dibutyryl cyclic adenosine monophosphate had no influence on the receptor. The TPA-induced and desipramine-induced decreases in beta-receptors were not additive, suggesting that a similar mechanism is involved. The infusion of the PK-C inhibitor 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H-7) caused an inhibition of the desipramine-induced decrease in beta-receptors. It is suggested that the beta-receptor down-regulation by antidepressants might be also regulated by PK-C through 5-HT-Ca2+-inositol-phospholipid systems.

A characteristic feature of antidepressant therapy is the lag phase in onset of clinical efficacy. This applies to both typical tricyclics agents and atypical antidepressants, mianserin or maprotiline. Attempts to delineate the molecular mechanisms of action of antidepressants on the basis of acute studies are limited value, and increasing attention is being focused on resultant adaptive changes stemming from their chronic treatment. The drug-induced adaptive modification can occur both pre-and postsynaptically. Regarding presynaptic sites, adaptation in the synthesis and release of norepinephrine (NE) and presynaptic alpha2-receptors and dopamine autoreceptors occur. However, the changes cannot be regarded as being primarily responsible for the therapeutic action of antidepressants. Chronic antidepressant treatments affect also post-synaptic aminergic systems eliciting a reduction of beta-adrenoceptors and in the sensitivity of NE-stimulated adenylate cyclase (NE-AC), and a decrease of 5HT2-receptors. The postsynaptic changes are more pertinent to the mechanisms of action of the drug. However, these properties can not extend to all atypical antidepressants. Fluoxetine, trazodone, alprazolam or MIA fails to alter beta-receptor density or the NE-AC sensitivity, and electroconvulsive therapy produces an increases in 5HT2 sites. More recently, new experiments demonstrate 1) a biomolecular linkage between 5HT and NE neuronal systems at the level of beta-receptors; 2) an acceleration of beta-receptor reduction with combined administration of antidepressants and alpha 2-receptor antagonists; 3) an existence of imipramine-like substance (endocoid) in the brain and a reduction of [3H]imipramine binding sites after chronic treatment with imipramine. While the end result downstream may be the same clinical efficacy, the initial biochemical steps leading to this goal may not be identical for all forms of antidepressants. It is expected that the new approaches can lead to the finding a common mechanism of action to all form of antidepressants.

The relative potencies of a variety of neuroleptic drugs and antidepressant agents in competing for the binding of 3H-clonidine and 3H-yohimbine to alpha 2-adrenergic receptors of the rat cerebral cortex were quantified. The rank order of potencies of neuroleptics tested in competing for both ligand bindings is: clocapramine, carpipramine much greater than perphenazine, fluphenazine, alpha,beta-flupentixol greater than propericiazine, levomepromazine greater than chlorpromazine, pimozide greater than moperone much greater than haloperidol, sulpiride. Among the antidepressants, mianserin is the most potent antidepressant. Amitriptyline has a substantial affinity, while desipramine, imipramine, and clomipramine are the least potent. It is concluded that a number of neuroleptics and antidepressant agents display a potent or moderate affinity to alpha 2-receptor sites. These findings support the suggestion that some neuroleptics enhance the release of norepinephrine (NE) mainly by acting on presynaptic alpha 2-receptors, and that the alpha 2-receptor blocking property may have an important role in the mechanism of the antidepressant effect of some neuroleptic compounds.