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Working memory (WM) is a function operating in three successive phases: encoding (sample trial), holding (delay), and retrieval (test trial) of information. Studies point to a possible implication of the thalamic reuniens nucleus (Re) in spatial WM (SWM). In which of the aforementioned 3 phases the Re has a function is largely unknown. Recently, in a delayed SWM water-escape task, we found that performance during the retrieval trial correlated positively with c-Fos expression in the Re nucleus, suggesting participation in retrieval. Here, we used the same task and muscimol (MUSC) inhibition or DREADD(hM4Di)-mediated inhibition of the Re during information encoding, right thereafter (thereby affecting the holding phase), or during the retrieval trial. A 6-hour delay separated encoding from retrieval. Concerning SWM, MUSC in the Re nucleus did not alter performance, be it during or after encoding, or during evaluation. CNO administered before encoding in DREADD-expressing rats was also ineffective, although CNO-induced inhibition disrupted set shifting performance, as found previously (Quet et al., Brain Struct Function 225, 2020), thereby validating DREADD efficiency. These findings are the first that do not support an implication of the Re nucleus in SWM. As most previous studies used T-maze alternation tasks, which carry high proactive interference risks, an important question to resolve now is whether the Re nucleus is required in (T-maze alternation) tasks using very short information-holding delays (seconds to minutes), and less so in other short-term spatial memory tasks with longer information holding intervals (hours) and therefore reduced interference risks., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Importance: Exfoliation syndrome is a systemic disorder characterized by progressive accumulation of abnormal fibrillar protein aggregates manifesting clinically in the anterior chamber of the eye. This disorder is the most commonly known cause of glaucoma and a major cause of irreversible blindness., Objective: To determine if exfoliation syndrome is associated with rare, protein-changing variants predicted to impair protein function., Design, Setting, and Participants: A 2-stage, case-control, whole-exome sequencing association study with a discovery cohort and 2 independently ascertained validation cohorts. Study participants from 14 countries were enrolled between February 1999 and December 2019. The date of last clinical follow-up was December 2019. Affected individuals had exfoliation material on anterior segment structures of at least 1 eye as visualized by slit lamp examination. Unaffected individuals had no signs of exfoliation syndrome., Exposures: Rare, coding-sequence genetic variants predicted to be damaging by bioinformatic algorithms trained to recognize alterations that impair protein function., Main Outcomes and Measures: The primary outcome was the presence of exfoliation syndrome. Exome-wide significance for detected variants was defined as P < 2.5 × 10-6. The secondary outcomes included biochemical enzymatic assays and gene expression analyses., Results: The discovery cohort included 4028 participants with exfoliation syndrome (median age, 78 years [interquartile range, 73-83 years]; 2377 [59.0%] women) and 5638 participants without exfoliation syndrome (median age, 72 years [interquartile range, 65-78 years]; 3159 [56.0%] women). In the discovery cohort, persons with exfoliation syndrome, compared with those without exfoliation syndrome, were significantly more likely to carry damaging CYP39A1 variants (1.3% vs 0.30%, respectively; odds ratio, 3.55 [95% CI, 2.07-6.10]; P = 6.1 × 10-7). This outcome was validated in 2 independent cohorts. The first validation cohort included 2337 individuals with exfoliation syndrome (median age, 74 years; 1132 women; n = 1934 with demographic data) and 2813 individuals without exfoliation syndrome (median age, 72 years; 1287 women; n = 2421 with demographic data). The second validation cohort included 1663 individuals with exfoliation syndrome (median age, 75 years; 587 women; n = 1064 with demographic data) and 3962 individuals without exfoliation syndrome (median age, 74 years; 951 women; n = 1555 with demographic data). Of the individuals from both validation cohorts, 5.2% with exfoliation syndrome carried CYP39A1 damaging alleles vs 3.1% without exfoliation syndrome (odds ratio, 1.82 [95% CI, 1.47-2.26]; P < .001). Biochemical assays classified 34 of 42 damaging CYP39A1 alleles as functionally deficient (median reduction in enzymatic activity compared with wild-type CYP39A1, 94.4% [interquartile range, 78.7%-98.2%] for the 34 deficient variants). CYP39A1 transcript expression was 47% lower (95% CI, 30%-64% lower; P < .001) in ciliary body tissues from individuals with exfoliation syndrome compared with individuals without exfoliation syndrome., Conclusions and Relevance: In this whole-exome sequencing case-control study, presence of exfoliation syndrome was significantly associated with carriage of functionally deficient CYP39A1 sequence variants. Further research is needed to understand the clinical implications of these findings.

Exfoliation syndrome (XFS) is the most common known risk factor for secondary glaucoma and a major cause of blindness worldwide. Variants in two genes, LOXL1 and CACNA1A, have previously been associated with XFS. To further elucidate the genetic basis of XFS, we collected a global sample of XFS cases to refine the association at LOXL1, which previously showed inconsistent results across populations, and to identify new variants associated with XFS. We identified a rare protective allele at LOXL1 (p.Phe407, odds ratio (OR) = 25, P = 2.9 × 10 -14 ) through deep resequencing of XFS cases and controls from nine countries. A genome-wide association study (GWAS) of XFS cases and controls from 24 countries followed by replication in 18 countries identified seven genome-wide significant loci (P < 5 × 10 -8 ). We identified association signals at 13q12 (POMP), 11q23.3 (TMEM136), 6p21 (AGPAT1), 3p24 (RBMS3) and 5q23 (near SEMA6A). These findings provide biological insights into the pathology of XFS and highlight a potential role for naturally occurring rare LOXL1 variants in disease biology.

To investigate the hemodynamics and myocardic contraction of the heart left ventricle, 61 patients with pulmonary tuberculosis (main group) and 26 healthy subjects (control group) were observed. Higher ultimate systolic and diasystolic volumes of the left ventricle and lower levels of the efflux fraction in the patients with active pulmonary tuberculosis were stated. There was shown inverse correlation of the systemic systolic arterial pressure and the left ventricle efflux fraction with ESR, evident of the tuberculosis intoxication. The most pronounced aggravation of the left ventricle function was recorded in the patients with the most severe tuberculosis process. The impairments in the left ventricle in the patients with active pulmonary tuberculosis were of functional nature. Due to intensive therapy of the tuberculosis, the indices of the left ventricle efflux function improved and the systemic arterial pressure came to normal, along with elimination of the tuberculosis intoxication signs.

The specific intravascular and central hemodynamic features were studied in 42 patients with pronounced posttuberculous changes in the lung in comparison to a group of healthy individuals without a history of tuberculosis. Along with clinical, functional, and electrocardiographic studies, the authors used echocardiography. End ventricular and atrial systolic and diastolic areas, end left ventricular systolic and diastolic volume, ejection fraction, stroke and cardiac indices were determined. Dilation of the right ventricle and right atrium and their increased specific contractility were ascertained in patients with pronounced posttuberculous changes. At the same time hypertrophy of the right ventricular wall was rarely observed. This gives grounds to regard dilatation of the right ventricle as an earlier sign of evolving chronic cor pulmonale that its hypertrophy. There were no changes in the left ventricle, left atrium, ejection fraction, stroke and cardiac indices, which was explained by the absence of intoxication and toxic infective action in the persons clinically recovered from tuberculosis.

The authors put forward a program of prevention of dysplastic arthrosis which is presented in graphic form with textual description. It has been worked out on the basis of the formerly elaborated conceptual model "Dysplasia of the joint-dysplastic arthrosis" and it is a complex of general medical prophylactic measures oriented towards the elimination of mutagenous environmental factors, i.e. towards prevention of morbidity and towards the treatment-and-rehabilitation orthopaedic measures directed at reduction of the risk of development of dysplastic arthrosis in the conditions of dysplastic lesion of the joint (prevention of the disease). The conditions necessary for carrying out this program are supposed to be: a diagnostic algorithm providing for revealing dysplastic lesions already at the preclinical stage; thorough quantitative and qualitative characteristics of the dysplastic process providing for planning of correct surgical interventions; prognostic evaluations presuming a probability of evolution of the dysplastic process and its outcome; and a system of stage-by-stage diagnostic and treatment-and-rehabilitation measures providing for achievement of the effect expected in each particular case. Three groups of surgical interventions have been pointed out: prophylactic, which are performed on the dysplastic joint in case of absence of dystrophic changes; therapeutic, which are performed in case of presence of reversible dystrophic changes (e.g. chondromalation at stages I and II); and palliative, which only result in temporary stabilization of the arthrosis process, i.e. leading to improvement.