An evaluation of two indirect methods of blood pressure measurement in ill patients

Direct (intraarterial) and two indirect (using a mercury sphygmomanometer [MS] and an automatic [auscultatory] device) methods of blood pressure measurement were compared in intensive care patients (N = 32). One trained observer blind to both automatic and direct measurements obtained all indirect MS measurements. All direct and indirect measurements were made on the same arm. Direct measurements were obtained from 10-second strip chart recordings. In normotensive patients both indirect measurements of systolic blood pressure (SBP) underestimated the direct SBP; however, only the SBP value obtained with the automatic device (106 mm Hg) was significantly different, p less than .05, from the direct SBP value (120 mm Hg). No significant difference was noted between methods in measurement of normotensive diastolic blood pressure. In hypertensive patients direct SBP was significantly greater, p less than .05, from both values obtained by indirect measurement. In patients without hypotension the automatic device may be substituted for the MS and direct blood pressure methods. The automatic device may offer the advantage of decreasing observer bias and variability in blood pressure measurement.     

Nerve growth factor and p75NGFR factor receptor mRNA change in rodent CNS following stress activation of the hypothalamo-pituitary-adrenocortical axis

The synthesis of nerve growth factor (NGF) by the hippocampus raises the possibility that NGF may play a role in the regulation of the hypothalamic-pituitary-adrenal axis (HPAA). Subchronic cold stress has been shown to activate the HPAA in a mild noninvasive manner, to stimulate serum glucocorticoid levels, and to perturb NGF binding in hippocampus and basal forebrain. One or repeated episodes of cold stress increased NGF mRNA levels in the hippocampus and p75^NGFR mRNA levels in the basal forebrain. These changes were not due to elevated serum glucocorticoid levels since treatment with exogenous corticosterone had no effect on NGF and p75^NGFR mRNA levels. Adrenalectomy did not prevent the stress induced increases in NGF and p75^NGFR mRNA. © 1993 Wiley-Liss, Inc.     

Kaposi's sarcoma tumor cells preferentially express Bcl-xL.

Several recently identified proteins such as Bcl-2 and Bcl-x have been found to regulate programmed cell death (i.e., apoptosis). In this report, we examined the levels of expression of proteins that can either prevent apoptosis (i.e., Bcl-2 or the long form of Bcl-x, designated Bcl-x1) or promote apoptosis (i.e., Bax or the short form of Bcl-x, designated Bcl-xs) in proliferating benign and malignant endothelial cells (ECs). In normal skin with quiescent ECs, no detection by immunohistochemical staining was observed for Bcl-xL, Bcl-xs, or Bcl-2. However, in diseased skin samples that feature a prominent angiogenic response such as in psoriasis or pyogenic granulomas, the proliferating ECs markedly overexpressed Bcl-xL, with little to no Bcl-2. In an acquired-immune-deficiency-syndrome-related neoplasm, Kaposi's sarcoma, the spindle-shaped tumor cells also overexpressed Bcl-xL compared with Bcl-2. These in vivo studies were extended in vitro using cultured ECs and Kaposi's sarcoma tumor cells that were examined by flow cytometry and immunoblot analysis. Both cultured ECs and Kaposi's sarcoma tumor cells express significantly higher levels of Bcl-xL than Bcl-2. Such overexpression of cell survival gene products may contribute to prolonging the longevity of EC-derived cells in several different benign and neoplastic skin disorders that are characterized by a prominent angiogenic tissue response.     

Guidelines for the collection, processing and storage of human bone marrow and peripheral stem cells for transplantation

SUMMARY. There are no current U.K. or international guidelines or regulations covering the production, processing and storage of haemopoietic cells such as to allow their engraftment following myeloablative therapy. This paper seeks to provide such guidelines. It enumerates how quality control and assurance can be applied to this area of transfusion medicine; procedural steps relating to bone marrow harvest on peripheral blood stem cell collection are outlined and recommended doses of nucleated cells suggested for both procedures. General specifications for identification, storage and transportation of bone marrow and peripheral blood stem cells are included and specific laboratory procedures related to the provision of haemopoietic cells for engraftment are outlined. Umbilical cord blood transplants and long-term bone marrow culture are alluded to but these are still in a research phase.     

Absence of tumorigenicity in athymic mice by normal human epidermal keratinocytes after culture in serum-free medium.

The very rapid growth rate (1 population doubling/day) of normal human epidermal keratinocytes (HK) cultured in serum-free medium can be utilized for wound closure in burn treatment. However, rapid growth in vitro may present the possibility of neoplastic transformation. To investigate this possibility, HK were cultured from primary isolation to large populations in MCDB 153 medium supplemented with epidermal growth factor (EGF, 10 ng/ml), insulin (5 micrograms/ml), hydrocortisone (0.5 micrograms/ml), and Bovine Pituitary Extract (BPE, 70 micrograms/ml). HK were studied for their ability to form tumors in athymic mice after subcutaneous inoculation. Sixteen separate HK strains were inoculated from primary cultures, or from secondary cultures either before or after storage in liquid nitrogen. Transformed cell lines, SCC 13 and FL, derived from human epithelial carcinomata were used as controls for tumor formation. HK formed no tumors (0/79) after 26 weeks incubation, SCC 13 formed nodular tumors (3/5) after 20 weeks incubation, and FL formed tumors (5/5) after 4 weeks incubation. HK cells were not found by histological examination of inoculation sites of keratinocyte cultures derived from primary culture from skin. In contrast, palpable tumors from both SCC 13 and FL were returned to tissue culture and continued to proliferate. These results support the conclusion that the rapid growth rate of human epidermal keratinocytes in vitro can be attributed to permissive culture conditions, and not to neoplastic transformation.     

Banach-Tarski paradox using pieces with the property of Baire

In 1924 Banach and Tarski, using ideas of Hausdorff, proved that there is a partition of the unit sphere S2 into sets A1,...,Ak,B1,..., Bl and a collection of isometries [sigma1,..., sigmak, rho1,..., rhol] so that [sigma1A1,..., sigmakAk] and [rho1B1,..., rholBl] both are partitions of S2. The sets in these partitions are constructed by using the axiom of choice and cannot all be Lebesgue measurable. In this note we solve a problem of Marczewski from 1930 by showing that there is a partition of S2 into sets A1,..., Ak, B1,..., Bl with a different strong regularity property, the Property of Baire. We also prove a version of the Banach-Tarski paradox that involves only open sets and does not use the axiom of choice.     

The mechanism of action of retrograde oxygen persufflation in renal preservation

Vascular perfusion of gaseous oxygen has been used to prolong the in vitro survival of a number of isolated organs, and has been shown to improve the hypothermic preservation of ischemically injured kidneys that were subsequently transplanted. We have investigated the mechanism of this effect. Rabbit kidneys were subjected to 60 min of warm ischemia prior to preservation for 24 hr with Ross, Marshall, and Escott's hypertonic citrate solution, with or without retrograde oxygen persufflation (ROP) via the renal vein. It was found that adenine nucleotide levels were almost doubled in the ROP-preserved kidneys, principally due to higher adenosine triphosphate (ATP) concentrations. It was shown that cytochrome oxidase activity was unaffected by ischemia or preservation method, but studies with the metabolic inhibitors ouabain and a mixture of cyanide and iodoacetate suggested that ATP was being synthesized during the storage period but was also being utilized to power the active volume-regulating pump. Morphological examination revealed a much greater degree of cell swelling and cytological injury in the kidneys not subject to ROP, and the interstitial space appeared much reduced in the latter group. At the ultrastructural level, the ROP-treated kidneys showed generally well-preserved mitochondria, mostly in the energized "orthodox" configuration. In contrast, the mitochondria in the nonpersufflated kidneys were generally in the "condensed" deenergized state. We conclude that the provision of sufficient oxygen by ROP allows the continued production of ATP in sufficient quantities to permit improved maintenance of cellular volume and morphology under the conditions of low-temperature storage that we have studied.