The time-dependent effects of hypoxia on the discharge rate carotid chemoreceptors were measured in anesthetized cats. Hypoxic exposure of two different durations were used: a short-term exposure (2–3 h) was used to measure the response of the same carotid chemoreceptors; and a long-term exposure (28 days at inspired PO2 of 70 Torr) to study carotid chemoreceptor properties in one group of cats relative to those of a control group. In the chronically hypoxic and control groups, determinations were made of the 1) steady-state responses to four levels of arterial PO2 (PaO2) at constant levels of arterial PCO2; 2) steady-state responses to acute hypercapnia during hyperoxia; and 3) maximal discharge rates during anoxia. We found that the acute responses of carotid chemoreceptor afferents to a given level of hypoxia (PaO2 = 30–40 Torr) did not significantly change within 2–3 h. After long-term exposure the carotid chemoreceptor responses to hypoxia significantly increased, with no significant changes in the hypercapnic response and in the maximal discharge rate during anoxia. We conclude that isocapnic hypoxia may not elicit a sufficient cellular response within 2–3 h in the cat carotid body to sensitize the O2 responsive mechanism, but hypoxia of longer duration will sensitize such a mechanism, thereby augmenting the chemosensory activity.

The history of medical records is thousand-year-long, with earlier roots in ancient civilizations. Until the 19th century, medical records mainly served educational purposes, later assuming other roles such as in insurance or legal procedures. This article comprehensively describes and reviews the development of medical records from ancient to modern times in Europe and North America, reflecting alterations and adaptations compliant with the mental and technological capabilities of a given period. We searched PubMed and Google Scholar databases to collect pertinent articles. English articles or those having English abstracts were considered. The search terms included “Medical Records,” “Health Records,” “History of Medicine,” and “eHealth” and covered the last hundred years. References were also picked out from the identified articles. Overall, 600 articles were identified, 158 of which were judged thematically relevant. The general conclusion is that medical records undergo a revolutionary change from paper-based to electronic format, which reflects the development of eHealth systems. The migration process to eHealth records involves the use of artificial intelligence (AI) algorithms that streamline medical services by using faster and simpler working methods. AI benefits both patients and providers as it improves patient management and communication among medical centers, spares resources, identifies contamination or infections, and limits health costs. These advantages have become pointedly apparent during the recent COVID-19 scourge.

Distinction between true negative and depressive symptoms in schizophrenia is difficult. In the present study we seek to establish the psychological profile of depression-prone schizophrenic patients. We addressed the issue by comparing the expression of psychological indices, such as the feelings of being in control of events, anxiety, mood, and the style of coping with stress in depressive and non-depressive schizophrenics. We also analyzed the strength of the association of these indices with the presence of depressive symptoms. A total of 49 patients (18 women and 31 men, aged 23-59) were enrolled into the study, consisting of a self-reported psychometric survey. We found that the prevalence of clinically significant depression in schizophrenic patients was 61%. The factors which contributed to the intensification of depressive symptoms were the external locus of control, anxiety, gloomy mood, and the emotion-oriented coping with stress. We conclude that psychological testing may discern those schizophrenic patients who would be at risk of depression development and may help separate the blurred boundaries between depressive and negative symptoms of schizophrenia.