Comparison of Non-contact Infrared Temperature with Digital Axillary Temperature

We measured the Non-contact infrared temperature (NCIT) fromthe forehead, chest and abdomen, and compared it with Digitalaxillary temperature (DAT) by Bland Altman Plot. The DAT agreedbetter with NCIT chest (mean difference 0.13, 95% limit ofagreement 0.08, 0.18) as compared to NCIT forehead andabdomen.

The effect of short-term hypothyroidism on growth hormone secretory responses to growth hormone-releasing hormone (1-29) and insulin-induced hypoglycemia

Introduction: Hypothyroidism is frequently associated with growth failure. In long-standing hypothyroidism the growth hormone (GH) secretory responses to growth hormone-releasing hormone (GRH) and insulin-induced hypoglycemia are decreased. Methods: To investigate whether hypothyroidism of short duration affects pituitary GH release, we measured the serum GH response to synthetic GRH (1-29), 1g/kg body weight, given IV to six athyreotic patients during thyroxine (T4) treatment and one month after stopping T4 (short-term hypothyroid state). This served as a direct measure of pituitary somatotroph function .We also assessed the serum GH response to insulin-induced hypoglycemia in three patients as an indirect assessment of hypothalamic function. Results: We found that basal GH levels remained the same both during (euthyroid state) and after stopping T4 therapy (hypothyroid state). Peak serum GH response to GRH was significantly greater in patients while they were hypothyroid than during T4 therapy when they were euthyroid (p< 0.01). There was no difference in the peak serum GH response to hypoglycemia during and after stopping T4 replacement (30.3 + 8.9 g/L euthyroid-state versus 45 + 14.5 g/L short term hypothyroid-state). Discussion: These results suggest that, in contrast to long standing hypothyroidism, thyroid hormone deficiency of short duration increases somatotroph sensitivity to GRH, perhaps as a result of decreased endogenous hypothalamic IGF-1 release and/or tone.

Profound Hypothermia Provides Neuroprotection Following Hypothermic Circulatory Arrest: Ultrastructural Observations.

Objective: To assess whether cooling to 10°C can reduce neurological injury during 75 minutes of hypothermic circulatory arrest (HCA) compared to cooling to 18°C. Methods: Twelve domestic swine were used for this prospective blind randomized study. The animals were divided into 2 groups: Group A (n=6) underwent hypothermic circulatory arrest at 18oC for 75 min, and Group B (n=6) underwent hypothermic circulatory arrest at 10oC for 75 min. At the end of the experiment, the brains were removed and immersed in paraformaldehyde. All brains were dissected in the sagital plane. Tissue blocks from the left hemisphere were cut to encompass the sensory neocortex. Results: The selected area was identified with a dissecting microscope. Samples were examined in a blind fashion using electron microscope. Two investigators were instructed to find 10 representative neurons and analyze electron micrographs of these neurons for evidence of nuclear and cytoplasmic changes. Similarly, each investigator was instructed to examine the perinuclear neuronal mitochondria for abnormalities in mitochondrial distribution. Significant differences were observed between the 2 groups in mitochondria and rough endoplasmic reticulum (RER). In 5 of the 6 animals treated with 18oC HCA, neurons had slightly dilated RER, Golgi apparatus and mitochondria. In all 6 animals treated with 10oC HCA, the structure of the cytoplasmic organelles was intact, with no apparent dilatation (p=0.015). Conclusion: This study adds further support that hypothermia at 10oC exerts better cellular protection than hypothermia at 18oC, as evidenced by these electron microscopy findings.

Supratentorial Dissection of the Human Brain for Neuroscientists.

Background: Recent clinical advancements, including brain imaging or target specific procedures, have increased the demand for a more advanced understanding of the structure of the brain. The need for a more sophisticated, functionally relevant understanding the structure of the brain has resulted in a surge of neuroanatomy dissection courses, including gross neuroanatomical observation, cross-sectioning, blunt dissection and various fiber dissection techniques. Methods: Sixteen (16) adult, formalin fixed cerebral hemispheres were included in this study. Surface anatomy, blunt dissection of the lateral ventricles, and cross-sectioning of the anterior portion of the hemisphere, was performed on all specimens. Results: A detailed, but simplified, protocol consisting of seven steps is proposed for the study of the supratentorial anatomy of the human brain. The first two steps promote an appreciation of the predominate structural pattern of the surface of the brain. Four distinct, consecutive dissection steps are recommended for the dissection of the ventricular system. Horizontal cross-sectioning of the anterior portion of the hemisphere is described in five sub-steps. Conclusion: Dissection methods described provides an appreciation of the predominate structural pattern of the surface of the brain, in relation to the deep the structures. This appreciation is gained through the step-by-step dissection of the ventricular system and cross-sections. In addition to understanding the surface-to-deep relationships, the hands-on practical study of the anatomy of brain as described herein, allows the observer to gain a true three-dimensional structural understanding of the human brain.