Acute pseudo-obstruction of the colon in thermally injured patients

Summary and Conclusions Five (1 per cent) of 529 thermally injured patients experienced pseudo-obstruction of the colon over a two-year period. All patients had classic non-painful abdominal distention. Infection was the most common associated problem and possible triggering mechanism in these patients. After confirmation of the colonic dilation on a plain abdominal roentgenogram, distal obstruction was ruled out by contrast enema. Occasionally, Gastrografin enema seemed to ameliorate the distention. Conservative medical management should be attempted initially. Colonoscopy should be employed at the earliest possible time. Exploratory laparotomy and tube cecostomy are usually adequate when surgical decompression is necessary. Patients who have accompanying small-intestinal distention seemed to tolerate this condition better, possibly due to a decompressing effect of an incompetent ileocecal valve. “Hinge-type” kinks, which occur in time at both hepatic and splenic flexures, become obstructing in themselves, and can be a barrier to conservative treatment. Read at the meeting of the American Society of Colon and Rectal Surgeons, San Diego, California, June 11 to 15, 1978. The opinions or assertions contained herein are the private view of the authors and are not to be construed as official or as reflecting the view of the Department of the Army or the Department of Defense.     

Localization of erythropoietin synthesizing cells in murine kidneys by in situ hybridization

In situ hybridization was used to localize the cells that produce erythropoietin (EP) in anemic murine kidneys. Kidneys from anemic and nonanemic mice were fixed and processed for paraffin embedding. Sections were hybridized with a 35S-labeled RNA probe complementary to mRNA coding for EP. An uncommon, but specific type of cell was intensely labeled in the cortices of anemic kidneys. The labeled cells were clearly nonglomerular and nontubular. Their location outside of the tubular basement membrane was consistent with that of a subset of interstitial cells or capillary endothelial cells.     

Enzymatic digestion of esophageal meat impaction

While a solution of Adolph's Meat Tenderizer^® (AMT) is commonly used to treat esophageal meat impaction, few studies describe its clinical effects. We examined AMT with regard to (1) its papain activity; (2) its ability to digest meat cubesin vitro; and (3) its effect on rabbit esophageal mucosa. A standard papain assay was developed against which the activity of AMT was compared. Proteolytic activity was detected in AMT only when the papain activators, 0.02 M cysteine and 0.008 M EDTA, were added to the system. Meat cubes incubated in AMT solution exhibited no evidence of digestion as determined by protein release or change in sample weight. A solution of AMT had no adverse effect on normal esophageal mucosa in rabbits, but significantly increased esophagitis when infused onto previously inflamed mucosa. We conclude that AMT solution has no inherent capacity to digest or to reduce the size of an impacted meat bolus, and may, in fact, worsen existing esophagitis.The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of the Army or the Department of Defense.Presented at the Twelfth Annual William Beaumont Gastrointestinal Symposium, March 23–25, 1983, El Paso, Texas.Address for reprint requests: Technical Publications Editor, Letterman Army Medical Center, Presidio of San Francisco, California 94129.     

CD44 mediates hyaluronan binding by human myeloid KG1A and KG1 cells

Hyaluronan-binding function of the CD44 molecule has not been so far detected in myeloid cells. To study pure populations of primitive myeloid cells, we investigated the hyaluronan-binding function of the CD44 molecule from three myeloid cell lines: KG1a, KG1, and HL60. Both KG1a and KG1 cells express the CD34 antigen characteristic of the hematopoietic stem cells and HL60 cells do not; accordingly, KG1a and KG1 cells are generally considered as the most primitive and HL60 cells as the most mature of these cell lines. Measurement of cell adhesion to hyaluronan-coated surfaces (using 51Cr-labeled cells) and of aggregate formation in hyaluronan-containing solutions, showed that 45% of KG1 cells and 22% to 24% of KG1a spontaneously bind to hyaluronan, whereas HL60 cells do not either spontaneously or after treatment with a phorbol ester. Hyaluronan binding by KG1a and KG1 cells is mediated by CD44, because it is specifically abolished by monoclonal antibodies (MoAbs) to this molecule. The binding might require phosphorylation by protein kinase C and perhaps also by protein kinase A, because it is prevented by staurosporine, which inhibits these enzymes. 12-O- tetradecanoylphorbol-13-acetate (TPA) which activates protein kinase C, rises to 80% the proportion of KG1 and KG1a cells that bind hyaluronan; this activation is dependent on protein synthesis, for it is abrogated by cyclophosphamide, a protein synthesis inhibitor. Binding of TPA- treated cells to hyaluronan is only partly inhibited by MoAb to CD44: this suggests that TPA may induce synthesis of a hyaluronan-binding protein distinct from CD44. Considering the abundance of hyaluronan in human bone marrow, these results suggest that CD44 may be involved in mediating precursor-stroma interaction.     

Regeneration of gastric mucosa after aspirin-induced injury in the rat

Regeneration of gastric mucosa damaged by aspirin was studied in 6-week-old rats, using histologic and autoradiographic technics. Aspirin (120 mg/kg) was given by esophageal intubation either in a single dose or each day for 14 days. After a single dose, two types of lesion were observed in the mucosa of the body of the stomach: (a) superficial erosions which were already present after 30 minutes and which completely healed within 24 hours; (b) deeper erosions, reaching maximal numbers at 4 hours, which healed slowly with a median disappearance time of 5 days and which were associated with a focal increase in³H-thymidine-labeled cells. The peak increase in labeling occurred between 16 and 48 hours. The pattern and rate of healing was not altered by repeated daily aspirin. The investigation has demonstrated slow healing of deep mucosal erosions caused by aspirin; the slow healing can be explained by destruction of the progenitor zone by the initial injury.Supported by the National Health and Medical Research Council and the Alfred Hospital.Presented in part to the Australian Society for Medical Research, December 1971.     

Relationship between urinary excretion of modified nucleosides and rheumatoid arthritis process

The levels of the five methylated nucleosides pseudouridine (psi-Urd), 1-methyladenosine (1-MeAdo), 4 acetylcytidine (4-AcCyd), 1 methylinosine (1-Melno) and 7 methylguanosine (7-MeGuo) resulting from RNA degradation were examined in the urine of rheumatoid arthritis (RA) patients. Of these five, 1-MeAdo and psi-Urd were correlated with the active phase of the disease, while two others (4-AcCyd and 1-Melno), which require further evaluation, appeared to be linked to the prognosis of the disease. As RNA turnover is closely associated with cell proliferation, including that of lymphocytes in RA, there may be a hitherto unsuspected benefit in measuring 1-MeAdo and psi-Urd as biochemical markers of RA disease activity.