Medical hypotheses
-
Hematopoietic stem cells transplantation has been wildly used in clinical settings and has shown exciting results in treating a wide variety of diseases. However, the relative small number of hematopoietic stem cells in bone marrow, even lower in peripheral or umbilical cord blood limits its clinical utility. There are several protocols, which have been developed to expand hematopoietic stem cells to reach clinical goal. ⋯ And the recombinant fusion proteins could be used in expanding hematopoietic stem cells. Meanwhile, Cdx4 fusion proteins would be more efficient than other methods that had been developed for it can up-regulate a cocktail of hox genes, which has been proved to be capable of amplifying hematopoietic stem cells. It would provide us an alternative protocol to amplify hematopoietic stem cells if the hypothesis proved to be practical.
-
The mechanisms responsible for symptom expression in fibromyalgia (FM) are complex. The most consistently detected objective abnormalities in FM involve pain-processing systems. Up to recently, central nervous system was a primary focus of investigations in FM. ⋯ This paper suggests that patients with FM represent a state of the dysfunction of descending, antinociceptive pathways and low hypothalamic-pituitary-adrenal function. This state is further proposed to result in many skin biopsy findings associated with the disorder, including increased N-methyl-d-aspartate receptors subtype 2D expression, neurogenic inflammation and characteristic electron microscopic findings. Future direction of research would be identification of specific laboratory markers such as skin biopsy for diagnostic and clinical evaluation purposes in FM.
-
Amniotic fluid embolism, a rare, sudden and often fatal illness of pregnancy may not be a true embolic event resulting from the physical obstruction of the pulmonary vasculature. The high degree of variability in symptoms, the lack of characteristic findings on radiological exam, the absence of a dose-response effect on symptoms, and the occasional occurrence of coagulopathies are not entirely consistent with a physical block to the circulation as the main mechanism of disease. Alternatively, it might be the result of complement activation initiated by fetal antigen leaking into the maternal circulation. ⋯ Direct measurement of serum complement as well as serum tryptase and urinary histamine are readily obtained tests in community hospitals as well as tertiary care hospitals. If the hypothesis proves true, this investigation may be of profound importance to understanding immune tolerance. Rather, than asking why one pregnant woman in 20,000 develops a violent immune reaction to the fetus, a better question is why do not all pregnant women reject the fetus which is a large collection of foreign antigens?
-
In a recent Medical Hypotheses editorial, I suggested the name psychological neoteny (PN) to refer to the widely-observed phenomenon that adults in modernizing liberal democracies increasingly retain many of the attitudes and behaviors traditionally associated with youth. I further suggested that PN is a useful trait for both individuals and the culture in modernizing societies; because people need to be somewhat child-like in their psychology order to keep learning, developing and adapting to the rapid and accelerating pace of change. Thirdly, I put forward the hypothesis that the major cause of PN in modernizing societies is the prolonged duration of formal education. ⋯ However, the economic effect is different in men and women: after parenthood men are more likely to have a job and work more hours while women change in the opposite direction. The conclusion is that psychological neoteny is indeed increasing, and mainly as a consequence of the increasing percentage of school leavers going into higher education. But at present it is unclear whether this trend is overall beneficial or harmful; and the answer may be different for men and women.
-
Postoperative delirium represents a serious complication after major surgery. Patients suffer from anxiety, hallucinations and delusions, and have higher postoperative morbidity and mortality. Generally, the role of acetylcholine deficiency in delirium pathophysiology is widely accepted. ⋯ These morphological changes lead to a decrease of nutritive perfusion and to longer diffusion distance for oxygen. Because acetylcholine synthesis is especially sensitive to low oxygen tension, symptoms of its deficiency readily develop. Therapeutic tools to modulate excessive inflammation are available, therefore new strategies of delirium treatment should be implemented in clinical praxis, as well as in preventive measures.