GABA-immunoreactive neurons and terminals in the cat periaqueductal gray matter: a light and electron microscopic study

Immunocytochemical and electron microscopic methods were used to study the GABAergic innervation in adult cat periaqueductal gray matter (PAG). A mouse monoclonal antibody against γ -aminobutyric acid (GABA) was used to visualize the inhibitory neuronal system of PAG. At light microscopy, GABA-immunopositive (GABA_IP) neurons formed two longitudinally oriented columns in the dorsolateral and ventrolateral PAG that accounted for 36% of the neuronal population of both PAG columns; their perikaryal cross-sectional area was smaller than that of unlabeled (UNL) neurons found in the same PAG subdivisions. At electron microscopic level, patches of GABA immunoreactivity were readily detected in neuronal cell bodies, proximal and distal dendrites, axons and axon terminals. Approximately 35–36% of all terminals were GABA_IP; they established symmetric synapses with dendrites (84.72% of the sample in the dorsolateral PAG and 86.09% of the sample in the ventrolateral PAG) or with cell bodies (7–10% of the sample). Moreover, 49.15% of GABA_IP axon terminals in the dorsolateral and 52.16% in the ventrolateral PAG established symmetric synapses with GABA_IP dendrites. Immunopositive axon terminals and unlabeled terminals were also involved in the formation of a complex synaptic arrangment, i.e. clusters of synaptic terminals in close contact between them that were often observed in the PAG neuropil. Moreover, a fair number of axo-axonic synapses between GABA_IP and/or UNL axon terminals were present in both PAG subdivisions. Several dendro-dendritic synapses between labeled and unlabeled dendrites were also observed in both PAG subdivisions. These results suggest that in the cat PAG there exist at least two classes of GABArgic neurons. The first class could exert a tonic control on PAG projecting neurons, the second could act on those GABAergic neurons that in turn keep PAG projecting neurons under tonic inhibition. The functional implications of this type of GABAergic synapse organization are discussed in relation to the dishinibitory processes that take place in the PAG.     

Correction to: Identifying Subgroups of Toddlers with DSM‑5 Autism Spectrum Disorder Based on Core Symptoms

Journal of Autism and Developmental Disorders - A correction to this paper has been published: https://doi.org/10.1007/s10803-021-04954-5     

Is it feasible to assess self-reported quality of life in individuals who are deaf and have intellectual disabilities?

Purpose

There is consensus that Quality of Life (QOL) should be obtained through self-reports from people with intellectual Disability (ID). Thus far, there have been no attempts to collect self-reported QOL from people who are deaf and have ID.

Methods

Based on an established short measure for QOL (EUROHIS-QOL), an adapted easy-to-understand sign language interview was developed and applied in a population (n = 61) with severe-to-profound hearing loss and mild-to-profound ID. Self-reports were conducted at two time points (t₁ and t₂), 6 months apart. The Stark QOL, an established picture-based questionnaire, was also obtained at t₂ and three Proxy ratings of QOL (from caregivers) were conducted for each participant at t₁.

Results

Self-reported QOL was successfully administered at both time points for 44 individuals with mild and moderate ID (IQ reference age between 3.3 and 11.8 years).

The self-reports showed sufficient test–retest reliability and significant correlations with the Stark QOL. As anticipated, self-reported QOL was higher than proxy-reported QOL. Test–retest reliability and internal consistency were good for self-reported QOL.

Conclusion

Reliable and valid self-reports of QOL can be obtained from deaf adults with mild-moderate ID using standard inventories adapted to the linguistic and cognitive level of these individuals.

     

Myocardial "bridges". A new pathogenetic problem in angina without coronary obstruction (author's transl)]

Six patients showing at coronary angiography normal coronary arteries during dyastole, but a segmental constriction of the left anterior descending artery during systole, were studied. Four of these patients in which the degree of systolic artery narrowing was more evident had typical angina and positive stress test. In two of these cases, a probable idiopathic cardiac hypertrophy was present. The pathogenetic significance of the angiographic findings are discussed, on the basis of common knowledge of coronary physiology and of pathophysiology of angina with normal coronary arteries.     

Incidence of reading disability in a population-based birth cohort, 1976-1982, Rochester, Minn.

OBJECTIVE: To report the incidence of reading disability among school-aged children. SUBJECTS AND METHODS: In this population-based, retrospective birth cohort study, subjects included all 5718 children born between 1976 and 1982 who remained in Rochester, Minn, after the age of 5 years. Based on records from all public and nonpublic schools, medical facilities, and private tutorial services and on results of all individually administered IQ and achievement tests, extensive medical, educational, and socioeconomic information were abstracted. Reading disability was established with use of research criteria based on 4 formulas (2 regression-based discrepancy, 1 non-regression-based discrepancy, and 1 low achievement). RESULTS: Cumulative incidence rates of reading disability varied from 5.3% to 11.8% depending on the formula used. Boys were 2 to 3 times more likely to be affected than girls, regardless of the identification methods applied. CONCLUSIONS: In this population-based birth cohort, reading disability was common among school-aged children and significantly more frequent among boys than girls, regardless of definition.     

Guidelines for health surveillance of health care workers exposed to biological risks set up by the Italian Society for Occupational Health and Industrial Hygiene: application in health facilities of the Regional Health Administration--District No. 7, Ancona

BACKGROUND: Evidence Based Medicine and the need to achieve better management of health budgets call for verification and, if necessary, revision of the criteria used in Occupational Health, in order to ensure appropriate measures as regards protection of health at the workplace. In December 2003, the Marche Region initiated a process of reform of the regional health service, which will be completed in two years, and will provide a new regional health organization that will improve the quality and appropriateness of health services available to the population. The reform also involves the Occupational Health Services responsible for prevention activities for 20,000 health care workers employed in regional public health facilities. The need was strongly felt to set up a network that would meet the health needs of health care workers, by adopting a common language among occupational health physicians, by eliminating reported criticism, which is due not only to lack of communication between different structures and profiles, but also to the different methods of approach, evaluation and management of occupational risks. OBJECTIVES AND METHODS: From a historical point of view, the health sector has the biggest as regards prevention of biological risk. Therefore, with a view to harmonizing actions and approach among occupational health physicians in the evaluation of this risk, the publication by the Italian Society for Occupational of Health and Industrial Hygiene of Guidelines for health surveillance of health care workers exposed to biological risks, produced by the working group under the leadership of Prof. Lorenzo Alessio, was considered to offer an interesting opportunity to verify the reproducibility of methods and the quality of results, as applied to health facilities under the Regional Health Administration in Ancona (District No. 7). RESULTS AND CONCLUSION: The Guidelines fully confirmed the need to plan activities, starting from analysis of epidemiological and occupational data, thus assuring good results both in terms of efficacy and efficiency of the health surveillance programme used. This method also assures a high level of appropriateness of medical measures as regards the "safety" target, at the same time avoiding waste and poor management of human and economic resources, which were till now caused by differences in methods used in assessment of biological risk.     

The incidence of autism in Olmsted County, Minnesota, 1976-1997: results from a population-based study

OBJECTIVE: To determine the incidence of autism among children in Olmsted County, Minnesota. DESIGN: Through the Rochester Epidemiology Project, all inpatient and outpatient diagnoses are indexed for computerized retrieval. This computerized diagnostic index was used to identify children with any developmental disorder. A glossary of symptoms of autism was used to review medical and school records of these children for symptoms consistent with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria for autistic disorder. SETTING: Olmsted County, Minnesota.Subjects All residents of Olmsted County 21 years or younger between 1976 and 1997.Main Outcome Measure The incidence of research-identified autism based on DSM-IV criteria for autistic disorder. RESULTS: The age-adjusted incidence of research-identified autism was 5.5 (95% confidence interval, 1.4-9.5) per 100 000 children from 1980 to 1983 and 44.9 (95% confidence interval, 32.9-56.9) from 1995 to 1997 (8.2-fold increase). This increase was confined to children younger than 10 years who were born after 1987. CONCLUSIONS: The incidence of research-identified autism increased in Olmsted County from 1976 to 1997, with the increase occurring among young children after the introduction of broader, more precise diagnostic criteria, increased availability of services, and increased awareness of autism. Although it is possible that unidentified environmental factors have contributed to an increase in autism, the timing of the increase suggests that it may be due to improved awareness, changes in diagnostic criteria, and availability of services, leading to identification of previously unrecognized young children with autism.     

Localization of the glutamine transporter SNAT1 in rat cerebral cortex and neighboring structures, with a note on its localization in human cortex

SNAT1 mediates glutamine (Gln) influx into neurons and is believed to replenish the transmitters pools of glutamate (Glu) and gamma-aminobutyric acid (GABA). We investigated its distribution and cellular localization in the cerebral cortex and neighboring regions of rats and humans using light and electron microscopic immunocytochemical methods with specific antibodies. In the first somatic sensory cortex of rats and in areas 9, 10, 21 and 46 of the human cortex, numerous SNAT1-positive (+) cells were present in the cortical parenchyma and in the white matter; >95% of SNAT1+ cells were neurons, but some were astrocytes. Most SNAT1+ cells were pyramidal neurons, but numerous non-pyramidal neurons were also observed: SNAT1/GABA double-labeling studies showed that SNAT1 is expressed in all GABA+ neurons. SNAT1/synaptophysin studies showed that <0.1% of all synaptophysin+ puncta coexpressed SNAT1. SNAT1 immunoreactivity (ir) was also in leptomeninges, ependymal cells and choroid plexus. Electron microscopic studies showed that neuronal SNAT1 ir was almost exclusively observed in perikarya and dendritic profiles. SNAT1 ir was also in distal astrocytic processes, including end feet profiles, and in leptomeninges. These findings suggest that the major function of SNAT1 is not to replenish the transmitter pools of Glu and GABA.