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Biomedical subjects

B Burke

Publications and source records attributed to B Burke.

At least 145 records · Page 8Linked to original sources

Ultrastructural and biochemical alterations in the livers from chick embryos maintained in shell-less culture.

Ultrastructural and biochemical studies were conducted on the livers from chick embryos maintained in shell-less culture up to stage 39 (Hamburger-Hamilton) and from control embryos developed in ovo up to the same stage. The ultrastructural characteristics of hepatic cells from the cultured embryos were similar to those found in the controls except that they contained many large lipid droplets and were almost devoid of lipoprotein granules normally associated with the Golgi complex and the smooth endoplasmic reticulum. These changes suggest the existence of alterations in the lipid metabolism. The livers from cultured embryos showed also a decreased incorporation of tritiated leucine into proteins, which indicates a reduced rate of protein synthesis. These results are consistent with previous reports showing that cultured embryos possess hypoproteinemia. Lactic dehydrogenase activity was similar and pyruvic kinase higher in the livers from cultured with respect to control embryos. This appears to indicate that both aerobic and anaerobic glycolysis were not depressed and that the changes observed in the rate of protein synthesis should not be attributed to hypoxia. "Fat-storing cells" similar to those described in mammals were found both in control and cultured embryos. They had not been previously described in the livers from chick embryos.

Animals↗

Cholestasis and hepatic metastases: a factor contributing to extreme elevations of carcinoembryonic antigen.

Records of 19 autopsied patients with metastatic carcinoma were studied to elucidate the contribution to the elevation of antemortem plasma carcinoembryonic antigen (CEA) levels (range, 5.9--136,000 ng/ml) of 1) liver pathology and dysfunction, 2) tumor morphology and CEA content, and 3) tumor spread and location. Liver function tests and plasma CEA recorded within 8 weeks of death, autopsy records of tumor spread, liver weight (as an index of liver tumor mass), and histologic sections were reviewed. Tissue CEA was demonstrated in 15 patients by an immunoperoxidase method. Cholestasis was seen in histologic sections of tissue from 8 of 10 patients, and elevated bilirubin was seen in 7 of 10 patients with hepatic metastases and CEA levels greater than 1,000 ng/ml In contrast, histologically observed cholestasis and elevated bilirubin were seen in only 1 of 8 patients with CEA less than 500 ng/ml. A significant correlation was found between the plasma CEA level and histologically observed cholestasis (P less than 0.01). Serum bilirubin also correlated significantly (P less than 0.01), but alkaline phosphatase did not. Liver weight (tumor mass) showed a positive correlation with cholestasis (P less than 0.01) but not with circulating CEA. Markedly elevated plasma CEA levels (greater than 1,000 ng/ml) seen preterminally may partially reflect impaired excretion of CEA by the hepatobiliary system rather than, or in addition to, preterminal increase in CEA-producing tumor.

Bilirubin↗

Total or near total pancreatectomy and islet autotransplantation for treatment of chronic pancreatitis.

Total or near total pancreatectomy is the surest way to relieve the pain of chronic pancreatitis but is rarely applied because the metabolic consequences are so severe. For most patients drainage procedures are applicable, but pancreatectomy may be the only alternative for small duct disease or where procedures to improve duct drainage have failed. Preservation of endocrine function is a major problem in patients who require pancreatectomy. Experiments in pancreatectomized dogs have shown that intrasplenic or intraportal transplantation of unpurified pancreatic islet tissue dispersed by collagenase digestion can prevent diabetes. We have applied this technique to ten patients with chronic pancreatitis, small ducts, and intractable pain. The entire pancreas of > 95% of the pancrease was excised, minced, dispersed by collagenase digestion and infused into the portal vein < 2 1/2 hours after removal. Mean (+/- SD) rise in portal pressure was 17 +/- 8 cm of water. Liver function tests were altered minimally. All patients were relieved of pain. One patient died of a complication not related to the islet autotransplant; viable islets were identified in the liver at autopsy. Of the remaining nine patients, three have been insulin independent for 1, 9, and 38 months. One patient was insulin indpendent for 15 months and now takes 12 units of insulin daily. Three have nonketosis prone diabetes (tested by insulin withdrawal) and take 15--30 units of insulin per day. C-peptide studies in these patients show that functioning islets are present. Two patients are diabetic and require 35 and 60 units of insulin per day. In eight of nine patients tested serum insulin concentrations fell to undetectable levels during the interval between pancreatectomy and islet transplantation. Serum insulin levels during the first few hours after islet transplantation predicted success. In the insulin independent or in the patients with mild diabetes, insulin levels were persistently greater than or equal to 6 microU/ml. In the other two patients, the increase in insulin concentration was not sustained. Islet tissue preparation from a diseased pancreas is difficult. The surgeon and the patient must still be willing to accept diabetes for relief of pain when performing this operation. In some patients, however, islet autotransplantation can prevent or partially ameliorate diabetes after pancreatectomy, and preservation of endocrine function is worthwhile.

Adult↗

Production of bacteremia and meningitis in infant rats with group B streptococcal serotypes.

Group B streptococcal strains, representing the five major serotypes, were inoculated into infant rats by intranasal, oral, and intraperitoneal routes. Bacteremia regularly followed injection by the intraperitoneal route. Four strains (three of type III) isolated from human cerebrospinal fluid appeared more virulent for 5-day-old rats. Injection of fewer than 10 colony-forming units of one strain, a type III, led to bacteremia and death in 27% of animals. The cumulative bacteremia and mortality rate with this strain was 66% in animals given inocula of less than 10 to 10(3) colony-forming units. Bacteremia developed by 24 to 48 h with concentrations of greater than 10(5) colony-forming units per ml of blood, and death occurred soon afterward. Among bacteremic animals, positive cerebrospinal fluid cultures were found in 97%, and cerebrospinal fluid bacterial concentrations were equal to or exceeded bacterial counts in blood. The susceptibility of infant rats to infection with type Ia, Ic, or III strains was age dependent. Histopathological studies of the brain and meninges in 34 bacteremic animals with culture-positive cerebrospinal fluid revealed that 5- to 10-day-old animals had numerous bacteria distributed in a perivascular pattern but, with one exception, no leukocytic infiltration. In contrast, three of the 11- to 12-day-old and two 15-day-old animals had very thickened meninges infiltrated with polymorphonuclear leukocytes, macrophages, and bacteria.

Animals↗

Immunochemical identification and determination of proline-rich proteins in salivary secretions, enamel pellicle, and glandular tissue specimens.

Acidic proline-rich proteins were localized histologically by means of the indirect immunoperoxidase technique in the acinar cells of parotid and submandibular gland sections of both man and Macaca fascicularis. These proteins were also identified as constituents of the long term in vivo-formed acquired pellicle on human tooth surfaces employing the same immunoperoxidase technique. Immunological quantitation of proline-rich proteins in whole and parotid saliva of 42 subjects indicates the presence of high concentrations in parotid secretions varying between 19-80 mg%, while their levels in whole saliva are significantly lower, ranging between 0-18 mg%. The concentrations of these proteins in whole saliva exhibited a negative correlation with plaque accumulation (r = -0.464) and gingival index scores (r = -0.576).

Animals↗

A double-blind trial of a zinc sulphate/citrate complex and tetracycline in the treatment of acne vulgaris.

Forty-eight patients participated in a 3-month double-blind study to compare the effect of orally administered zinc sulphate/citrate complex and tetracycline hydrochloride in acne vulgaris. Tetracycline significantly reduced the overall grade, and the number of non-inflamed lesions, papules and pustules by the third month. It also reduced significantly the non-inflamed lesions and papules at the end of the second month. In contrast, zinc therapy only had a significant effect on the pustules at the third month. The results indicate that tetracycline is far superior to the zinc complex in patients with moderately severe acne.

Acne Vulgaris↗

Abnormal characteristics of the blood from chick embryos maintained in "shell-less" culture.

Chick embryos were maintained in shell-less culture up to a total age of 15 days. The composition of their blood was analyzed together with the blood from coontrol embryos of comparable degree of differentiation. The blood from cultured embryos had lower hematocrit values; their serum contained a reduced concentration of proteins, phospholipids and total calcium and an increased concentration of inorganic phosphorus. In view of the reduced concentration of proteins and phospholipids, the concomitant hypocalcemia must represent, at least in part, a reduction in the binding capacity of the serum and not only a decrease in the ionic fraction of serum calcium.

Animals↗

The shape of spectrin molecules from human erythrocyte membranes.

Purified spectrin dimers and tetramers have been directly visualized by low-angle shadowing. The 9-S heterodimer is an asymmetric flexible molecule about 1000 A in length, its constituent monomer polypeptides forming two strands which in many molecules are individually visible, lying partially separated from one another or twisting round each other in a loose double helix. The 12-S tetramer is formed by the end-to-end association of two heterodimers, without overlap. The protein bears no physical resemblance to myosin.

Erythrocyte Membrane↗

Tissue localization of zinc glycinate marker and carcinoembryonic antigen by immunofluorescence. II. Immunofluorescence microscopy.

Preliminary indirect immunofluorescence studies on the zinc glycinate marker (ZGM) were compared with carcinoembryonic antigen (CEA) immunofluorescence, ZGM, detected in 26 of 29 human colon adenocarcinomas, was associated with the epithelial component of the malignant glands. Fluorescence was generally less strong and more granular for ZGM than for CEA and was found in intraglandular spaces, luminal border areas, and cytoplasm. ZGM concentration and tissue localization appeared to be related to tumor differentiation. ZGM was also detected in benign colon mucosae (adjacent to and distant from the carcinomas) from patients with colon carcinoma, but differed from CEA in that it was present in the deep crypt portion only. Gastric, pancreatic, esophageal, and anal adenocarcinomas, as well as benign gastric pyloric and small bowel mucosae had detectable ZGM. CEA, but not ZGM, was observed in 20 nongastrointestinal carcinomas to date. Studies are under way to determine whether ZGM is a marker associated with colon and gastrointestinal adenocarcinoma specifically or undifferentiated crypt cells of the colon and digestive tract in general.

Adenocarcinoma↗

Central hypoventilation syndrome: experience with bilateral phrenic nerve pacing in 3 neonates.

Successful long-term phrenic nerve pacing has been reported in adults with acquired central hypoventilation syndrome. This report summarizes our experience with phrenic nerve pacing in 3 infants with congenital central hypoventilation syndrome. The electrodes were implanted in the lower thoracic portion of each phrenic nerve. In all patients. bilateral simultaneous pacing was required to maintain an adequate arterial PO2, tidal volume, and minute ventilation during quiet sleep. Case 1 died of problems primarily related to the severe cor pulmonale that had been present before pacemaker insertion; at autopsy, the pacemaker system was intact and there were no significant phrenic nerve abnormalities. Case 2 later developed failure of awake ventilatory control and died because of extensive phrenic nerve damage incurred by 19 days of continuous pacing. Case 3 has received quiet sleep pacemaker support since September 1977 and has been able to maintain normal quiet sleep ventilation in this manner. Phrenic nerve pacing can be successful in infants as long as continuous pacing is not required. Bilateral simultaneous pacing appears to be an appropriate alternative to home-based intermittent positive-pressure breathing for long-term management of children with central hypoventilation syndrome.

Electric Stimulation↗

The distribution and excretion of non-biodegradable anionic surfactants.

1. The metabolism of potassium 10-undecenyl [35S]sulphate and potassium 10-phenyldecyl [35S]sulphate was investigated in the rat. 2. The major route for elimination of radioactivity following potassium 10-undecenyl [35S]sulphate administration was urinary. With 10-phenyldecyl [35S]sulphate the major route of elimination was biliary. 3. Whole-body radioautography and isolated liver perfusion experiments established that both esters were concentrated in the liver, the major organ of metabolism. 4. Neither surfactant was degraded to short-chain anionic derivatives but both compounds were extensively metabolized.

Animals↗

Characterization of L5178Y leukemic cells by phagocytosis, cytochemical methods, and membrane marker techniques.

Membrane marker techniques, endocytosis, and cytochemical methods were used to characterize L5178Y cells. L5178Y cells were found to have surface membrane immunoglobulin that typifies B-cells, and membrane receptors that are common to both B-cells and monocytes. L5178Y cells also have endocytic and enzymatic activities that are characteristic of monocytes. Thus L5178Y cells have the dual characteristics of B-cells and monocytes.

Animals↗

Recurrence of membranoproliferative glomerulonephritis following kidney transplantation. Serum complement component studies.

Sixteen patients with membranoproliferative glomerulonephritis who required kidney transplantation because of renal failure were evaluated for evidence of recurrence of the original disease by serologic and morphologic studies. Of the 12 patients with transplant tissue available for study, seven showed membranoproliferative glomerulonephritis by light morphology. Four of these seven also had hypocomplementemia, and this hypocomplementemia was characterized by decreased serum CH50, C3 beta1A or C3-C9 but norma serum C1, C4 and C2 by hemolytic assay. Immunofluorescent microscopy demonstrated more intense glomerular deposition of C3 and properdin in the hypocomplementemic patients. Ultrastructural studies demonstrated intramembranous deposits typical of dense deposit disease in one patient who also had marked hypocomplementemia. One patient who had two transplant biopsies and persistent hypocomplementemia showed progression from predominantly mesangial glomerular changes to both capillary wall and mesangial abnormalities. This study has shown a high rate of recurrence of membranoproliferative glomerulonephritis in the transplanted kidneys. A high death rate was noted in persistently hypocomplementemic patients. The serum C profile in hypcomplementemic patients who received translants was similar to that seen before transplantation, but the signficance of this finding remains unknown.

Adolescent↗

Extramembranous glomerulonephritis in childhood: relationship to systemic lupus erythematosus.

Extramembranous glomerulonephritis is an uncommon but distinct pathologic lesion in children. The diagnosis is established by the characteristic light, immunofluorescent, and ultrastructural abnormalities in renal biopsy specimens. This report describes seven of the ten children with this lesion studied in the past 11 years. Emphasis is given to the comparison of four children with idiopathic membranous glomerulonephritis with three others who presented with a nephrotic syndrome but subsequently developed evidence of systemic lupus erythematosus. Two of the latter three children, and three others with SLE and MGN not described in detail, demonstrated deposition of IgA by immunofluorescence along glomerular capillaries. Five of six children with SLE and MGN had microtubular structures in glomerular endothelial cells demonstrable by electron microscopy. These observations suggest that children with MGN require careful and continuing study for evidence of SLE.

Adolescent↗

The biodegradation of the surfactant undecyl sulphate.

1. The metabolism of the odd-numbered carbon chain surfactant, potassium undecyl [35S]sulphate in the rat was investigated. 2. The major route for elimination of radioactivity was the urine, regardless of the route of administration. 3. The surfactant was extensively degraded in vivo to yield propionic acid 3-[35S]sulphate, the major radioactive component in urine. A second urinary metabolite was identified tentatively as pentanoic acid 5-[35S]sulphate. 4. Whole-body autoradiography revealed the liver as the major site of metabolism. 5. The nature of the metabolic products of undecyl sulphate suggest that it is bio-degraded by initial omega-oxidation followed by beta-oxidation.

Animals↗

The biodegradation of some anionic detergents in the rat. A common metabolic pathway.

1. The metabolism of the anionic detergents potassium decyl [35S]sulphate and potassium octadecyl [35S]sulphate was investigated in the rat. 2. The major route for elimination of radioactivity was urinary regardless of the route of administration. 3. Both surfactants were extensively degraded in vivo to yield a common metabolite, butyric acid 4-[35S]sulphate, the major urinary radioactive component. 4. Whole-body radioautography revealed the liver as the major site of cellular accumulation of radioactivity following administration of either compound indicating the liver as the major site of metabolism. 5. It is suggested that alkyl sulphates with even-numbered carbons are degraded by a common pathway involving omega-oxidation followed by beta-oxidation.

Administration, Oral↗