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(CH3NH3)5Bi2Br11 (MAPBB) crystals exhibits ferroelectrics phase transitions at 311 K and additional anomaly of physical properties at 77 K. The results of temperature study of the specific heat for the (CH3NH3)5Bi2Br11 crystals are presented at temperature range of 6-277 K. The characteristic anomaly of temperature dependence of specific heat was observed at 72.4 K. It was established, that description of the experimental Cυ(T) dependence at temperatures below anomaly can be achieved with two Debye functions (ΘD(1) = 47 K and ΘD(2) = 215 K) and one low-frequency Einstein-type term (ΘE = 73 K). In order to fit Cυ in the temperature range above the anomaly another Einstein-like term with ΘE = 233 K must be included with double number of modes. The entropy AS connected with the low temperature anomaly reaches the magnitude of 2Rln2. [ABSTRACT FROM AUTHOR]

A successful positron emission tomography imaging program involving carbon-11 radiotracers demands fast, efficient, and reliable synthesis methods, requiring an on-site cyclotron and radiochemistry group, as well as clinical staff trained to operate under the unique constraints of the carbon-11 radionuclide. This study examines the merits and advantages of a captive solvent 'loop method' of radiolabeling four tracers with the carbon-11 radionuclide, producing the radioligands [ 11 C]ER-176, [ 11 C]MRB, [ 11 C]mHED, and [ 11 C]PiB. The 'loop method' is compared against the traditional reactor-based method of carbon-11 methylation in the course of synthesizing the same radiotracers on the identical automated platform. Further, a complete overview of the clinical research preparation of the [ 11 C]ER-176 radiotracer is presented. As demonstrated by the production of [ 11 C]ER-176, the captive solvent 'loop method' of heterogeneous alkylation proved to be more efficient, with excellent radiochemical purity (99.6 ± 0.6%, n = 25), higher and more consistent radiochemical yield (end of synthesis (EOS) = 5.4 ± 2.2 GBq, n = 25) compared to the reactor method (EOS = 1.6 ± 0.5 GBq, n = 6), increased molar activity (loop method = 194 ± 66 GBq/µmol, n = 25; reactor method = 132 ± 78 GBq/µmol, n = 6), along with an average 5 min shorter reaction sequence.

A novel gas chromatography method was developed using automatic injections to identify and quantify the amount of residual solvents or analytes in samples of fluorine-18 and carbon-11 radiopharmaceuticals. This approach evaluates seven analytes in less than 5 versus 13 min of acquisition time. The method additionally includes a 3 min bakeout to aid in the removal and carry-over of higher-boiling impurities. Chromatographic parameters such as column temperature, hold time, column pressure, flow rate, and split ratios were adjusted and optimized to analyze radioactive drug samples containing analytes which include methanol, ethanol, acetone, acetonitrile, triethylamine, N , N -dimethylformamide, and dimethyl sulfoxide. The relative standard deviation for each solvent was determined to be no greater than 1.6%. The method limit of detection (LOD) and limit of quantification (LOQ) were between 0.053 and 0.163 and 0.000 (5.791 × 10 -6 ) and 0.520 mg/mL, respectively. This GC technique, using flame ionization detection (FID), was validated and is currently employed for the routine quality control of all approved IND and RDRC PET radiopharmaceuticals at our center.

Background: Preclinical studies indicate that cannabidiol (CBD), the primary nonaddictive component of cannabis, has a wide range of reported pharmacological effects such as analgesic and anxiolytic actions; however, the exact mechanisms of action for these effects have not been examined in chronic osteoarthritis (OA). Similar to other chronic pain syndromes, OA pain can have a significant affective component characterized by mood changes. Serotonin (5-HT) is a neurotransmitter implicated in pain, depression, and anxiety. Pain is often in comorbidity with mood and anxiety disorders in patients with OA. Since primary actions of CBD are analgesic and anxiolytic, in this first in vivo positron emission tomography (PET) imaging study, we investigate the interaction of CBD with serotonin 5-HT 1A receptor via a combination of in vivo neuroimaging and behavioral studies in a well-validated OA animal model., Methods: The first aim of this study was to evaluate the target involvement, including the evaluation of modulation by acute administration of CBD, or a specific target antagonist/agonist intervention, in control animals. The brain 5-HT 1A activity/availability was assessed via in vivo dynamic PET imaging (up to 60 min) using a selective 5-HT 1A radioligand ([ 18 F]MeFWAY). Tracer bindings of 17 ROIs were evaluated based on averaged SUVR values over the last 10 min using CB as the reference region. We subsequently examined the neurochemical and behavioral alterations in OA animals (induction with monosodium iodoacetate (MIA) injection), as compared to control animals, via neuroimaging and behavioral assessment. Further, we examined the effects of repeated low-dose CBD treatment on mechanical allodynia (von Frey tests) and anxiety-like (light/dark box tests, L/D), depressive-like (forced swim tests, FST) behaviors in OA animals, as compared to after vehicle treatment., Results: The tracer binding was significantly reduced in control animals after an acute dose of CBD administered intravenously (1.0 mg/kg, i.v.), as compared to that for baseline. This binding specificity to 5-HT 1A was further confirmed by a similar reduction of tracer binding when a specific 5-HT 1A antagonist WAY1006235 was used (0.3 mg/kg, i.v.). Mice subjected to the MIA-induced OA for 13-20 days showed a decreased 5-HT 1A tracer binding (25% to 41%), consistent with the notion that 5-HT 1A plays a role in the modulation of pain in OA. Repeated treatment with CBD administered subcutaneously (5 mg/kg/day, s.c., for 16 days after OA induction) increased 5-HT 1A tracer binding, while no significant improvement was observed after vehicle. A trend of increased anxiety or depressive-like behavior in the light/dark box or forced swim tests after OA induction, and a decrease in those behaviors after repeated low-dose CBD treatment, are consistent with the anxiolytic action of CBD through 5HT 1A receptor activation. There appeared to be a sex difference: females seem to be less responsive at the baseline towards pain stimuli, while being more sensitive to CBD treatment., Conclusion: This first in vivo PET imaging study in an OA animal model has provided evidence for the interaction of CBD with the serotonin 5-HT 1A receptor. Behavioral studies with more pharmacological interventions to support the target involvement are needed to further confirm these critical findings., Competing Interests: Competing interests: The authors declare that they have no competing interests.

Dissection of the interior carotid artery is rare in the general population. It can however be a potentially life-threatening condition. In the group of patients below 45 years of age, it constitutes a fairly common cause of cerebral stroke., A Case Report: The study describes the case of a patient with the right interior carotid artery dissection, sustained most probably in the course of work. The patient was admitted to hospital for a severe headache of a few days' duration accompanied by Horner's syndrome on the right side. Promptly undertaken diagnostic procedures allowed for immediate diagnosis and application of the right treatment. The check-up examinations performed showed a healed artery and withdrawal of the neurological syndrome., Conclusions: The case emphasizes the role of prompt diagnosis and treatment in preventing the development of more serious complications. The article refers also to the standards of treating the dissection of the interior carotid artery which still arouse controversies., (© 2021 MEDPRESS.)

Importance: Despite favorable national trends in the incidence of end-stage renal disease (ESRD) from 2008 to 2011, ESRD incidence has been increasing recently, and less than 10% of patients with ESRD start renal replacement therapy with peritoneal dialysis (PD) in the United States. Given known and potential advantages of PD over hemodialysis, the Kaiser Permanente Northern California integrated health care delivery system implemented a program to expand use of PD., Objectives: To describe the system-level approach to expansion of PD use and temporal trends in initiation and persistence of PD and its associated mortality., Design, Setting, and Participants: This retrospective cohort study included adult members of a large integrated health care delivery system in Northern California who initiated chronic dialysis therapy from January 1, 2008, through December 31, 2018. Data were analyzed from March 1, 2018, through May 31, 2019., Exposure: From 2008 to 2018, Kaiser Permanente Northern California implemented a multidisciplinary, system-wide approach to increase use of PD that included patient and caregiver education, education and support tools for health care professionals, streamlined system-level processes, monitoring, and continuous quality improvement., Main Outcomes and Measures: Temporal trends in the proportion of patients starting chronic dialysis with PD vs hemodialysis compared with national trends. Secondary outcomes included persistence of PD at 1 year in those initiating it and standardized 1-year mortality rates in those initiating PD or hemodialysis., Results: Among 13 500 eligible health plan members in the study population (7840 men [58.1%] and 5660 women [41.9%]; mean [SD] age, 64.3 [14.4] years), initiation of PD increased from 165 of 1089 all new dialysis patients (15.2%) in 2008 to 486 of 1438 (33.8%) in 2018, which was substantially higher than national trends (6.1% in 2008 and 9.7% in 2016). Among the 2974 patients who initiated PD from 2008 to 2017, 2387 (80.3%) continued PD at 1 year after initiation, with a significant increase in age-, sex-, and race-standardized rates from 2008 (69.1%) to 2017 (84.2%). Age-, sex-, and race-standardized 1-year mortality for patients receiving PD and hemodialysis did not change significantly across this 10-year period (17.3% to 15.5% for hemodialysis, P = 0.89 for trend; and 5.5% to 7.3% for PD, P = 0.12 for trend)., Conclusions and Relevance: This study suggests that large-scale expansion of PD is feasible using a multidisciplinary, integrated, coordinated care approach; we believe these findings represent a national opportunity to improve outcomes for patients with advanced kidney disease.

Objectives: Epicardial left atrial appendage (LAA) closure with use of occluder is an emerging technique. Absence of remnant LAA stump is major criterion of successful obliteration. The aim of study was to assess early success rate of epicardial LAA closure., Methods: Fifteen patients with persistent AF and coronary artery disease underwent off-pump coronary revascularization with concomitant ablation and LAA epicardial occlusion with use of two types of occluders. Before incision and after appendage closure, TEE was performed to assess the LAA anatomy, diameter of left atrial ridge, and remnant LAA stump after occlusion., Results: In 80% (12) of patients, formation of a left atrial diverticulum was observed with the left atrial ridge forming the superior boundary. In 5 patients (33%), a minimal remnant LAA stump was found, none exceeding 1 cm (average length: 1.5 ± 2.3 mm). In all patients, blood flow in LAA cavity distal to the occluder was absent. There was no significant difference in LAA type, average left atrial diameter, LAA orifice, LAA length, left atrial ridge, or size of occluder used between patients with and without a remnant LAA stump. Occurrence of a remnant LAA stump correlated significantly with unfavorable anatomy (LAA orifice < 20 mm and LA ridge > 5 mm; r = 0.5774, P = 0.02)., Conclusion: The early success of epicardial LAA occlusion is not dependent on LAA morphologic type or occluder used. A minimal remnant LAA stump not exceeding 1 cm in length without distal blood flow was observed in one-third of the cases., (© 2016, Wiley Periodicals, Inc.)