Upsala journal of medical sciences
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This is a personal account of how studies of the pharmacology of opiates led to the discovery of a family of endogenous opioid peptides, also called endorphins. The unique pharmacological activity profile of opiates has an endogenous counterpart in the enkephalins and beta-endorphin, peptides which also are powerful analgesics and euphorigenic agents. The enkephalins not only act on the classic morphine (mu-) receptor but also on the delta-receptor, which often co-exists with mu-receptors and mediates pain relief. ⋯ Both dynorphins and nociceptin have modulatory effects on several CNS functions, including memory acquisition, stress and movement. In conclusion, a natural product, morphine and a large number of synthetic organic molecules, useful as drugs, have been found to probe a previously unknown physiologic system. This is a unique development not only in the neuropeptide field, but in physiology in general.
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Human papillomaviruses (HPVs) comprise a large group of small DNA tumor viruses with tropism for squamous epithelial cells. The papillomavirus life cycle is strictly linked to the epithelial differentiation program and production of virus particles is dependent on terminal cell differentiation. The virus structural proteins L1 and L2 are therefore detected only in the upper layers with differentiated cells in the infected epithelium. ⋯ It is reasonable to speculate that the differentiation dependent production of L1 and L2 and the differences in L1 and L2 protein levels among various HPV types reflect an adaptation of the viruses to the environment of the host that results in escape from the immune surveillance for various periods of time and efficient transmission of virus in the human population. Our research group is interested in the regulation of expression of the HPV structural proteins L1 and L2. The results of our research are summarised in this article.
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A relationship has previously been described between individual mean isoflurane concentrations and the release of a marker of neuronal injury, adenylate kinase (AK), into the cerebrospinal fluid (CSF) after anaesthesia and orthognathic surgery. Likewise, reduced mental performance has been detected. Twenty-nine patients scheduled for orthognathic surgery were assigned to isoflurane- or propofol based anaesthesia, which was adjusted to a defined level with the aid of processed EEG and quantitative surface EMG. ⋯ When five of the failed patients were re-examined 12-30 months later, three patients still performed poorly in the tests. Biochemical and neuropsychological disturbances were recorded in several patients objected to orthognathic surgery. The underlying mechanisms are unclear, including the role of the anaesthetic drugs or surgery itself.
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In an experimental study we determined the response trigger delay time of three infant ventilators with a capacity to detect and support spontaneous breathing. We measured this in anaesthetized cats as the time between the start of phrenic nerve activity and the increase in airway pressure caused by the subsequent inflation. Two modes of ventilatory support were used, namely Assist/Control (A/C) and synchronised intermittent mandatory ventilation (SIMV). ⋯ A higher set sensitivity reduced the response time. We conclude that triggered ventilation may be used in infants, at least when the spontaneous breathing rate is below 60 breaths per minute. This mode of ventilation could be useful when infants are to be weaned off the ventilator.
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In order to study if oxygen saturation in mixed venous blood (SvO2) could be used as a marker for heart performance, oxygen delivery (DO2) or consumption (VO2) in critically ill patients 134 hemodynamic measurements were performed by a thermodilution pulmonary catheter in 23 patients after abdominal aortic aneurysm surgery. These data were compared to 200 measurements performed in 30 patients with septic shock. When analysed on an individual basis SvO2 was only closely related to DO2 or VO2 in a minority of the patients. ⋯ On the other hand SvO2 was found to be an excellent marker for oxygen extraction (OER) in both groups of patients (median r = 0.98. p < 0.0001). In conclusion, the present study shows that SvO2 could not be used as a reliable marker for the important hemodynamic variables CI, DO2 or VO2 in critically ill patients. However, SvO2 was found to be an excellent marker for OER.