Search PubMed⌕ Search

Biomedical subjects

R Arnold

Publications and source records attributed to R Arnold.

At least 487 records · Page 27Linked to original sources
PubMed1985

Extramedullary haemopoiesis after bone marrow transplantation.

44 patients underwent bone marrow transplantation (BMT) for treatment of severe aplastic anaemia or haematological malignancies. During their post-transplant phase all patients had erythroblasts and granulocytic precursors in their peripheral blood. 15 patients died between day +6 and +346 after BMT and autopsies were performed. The sections of all 15 patients revealed extramedullary haemopoiesis in the spleen. Extramedullary haemopoiesis in the liver was found only in those patients who died early (between d +6 and d +21 after BMT). Medullary haemopoiesis, normally only occurring in the vertebral body, was also observed in the shaft of the femur. The present data show that after BMT all tissues with a haemopoietic matrix in ontogenesis can be repopulated with haemopoiesis in the early phase of reconstitution, possibly to compensate for the haemopoietic insufficiency after conditioning therapy. The expansion of haemopoiesis in the later period of up to 1 year after BMT, remains to be explained.

Acute Disease↗
PubMed1985

Structure of the oviducal epithelium of the brush-tailed possum (Trichosurus vulpecula).

Observations were made using scanning and transmission electron microscopy and were correlated with measurements of the mean surface area and the percentage area occupied by secretory cells to provide precise interpretation of the morphological data. In cyclic and anoestrous possums the oviducts were lined with elaborate folds of mucosa except in the portion of the isthmus adjacent to the uterus where the pattern was much simplified. The folds decreased in height and number after ovariectomy. Secretion was maximal between oestrus and Day 2 of the cycle when most ovulations take place. Extrusion of vesicles was observed in the ampulla and isthmus at this stage although the process was localized to some extent because groups of cells with actively extruding vesicles were interspersed with others which contained vesicles but otherwise appeared inactive. This is interpreted as a device whereby a constant supply of secretion can be maintained over several days. Secretory activity declined between Days 3 and 8 and the epithelium in mid-cycle (Days 8-18) appeared relatively quiescent. By Day 24 there was morphological and morphometric evidence of a return to oestrous conditions, although vesicles had not yet reappeared in secretory cells. Ciliogenesis was prevalent at this time and is probably related to the ovum transport that will occur several days later.

Animals↗
PubMed1985

Structure of the uterine luminal epithelium of the brush-tailed possum (Trichosurus vulpecula).

Morphology and morphometry of the luminal surface of the uterus of the brush-tailed possum were studied during the oestrous cycle, in anoestrous animals and after ovariectomy. At oestrus the secretory cells were small and the epithelium heavily ciliated. The relative surface area occupied by secretory cells reached a maximum on Day 13 when plasma progesterone concentrations are maximal. The mean apical surface area of the secretory cells also reached a maximum at this time. Both these measures decreased on Day 18 when involution of the epithelium was taking place. This process was essentially complete by Day 24 and was followed by extensive ciliogenesis. Secretory cells from anoestrous animals appeared to have an apical surface area similar to the minimum recorded during the oestrous cycle and extensive loss of cilia did not occur. Ovariectomy caused loss of ciliated cells and a reduction in the mean apical surface area to a dimension much smaller than that measured in intact animals.

Anestrus↗
PubMed1985

[Hormone-producing (paracrine) cells in the human labyrinth].

Presence of immunoreactive somatostatin in the covering epithelial cells of the spiral prominence was demonstrated by immunohistochemical methods. The concentration of somatostatin increases from the basal turn to the apical turn of the cochlea. Ultrastructural investigations of these cells reveal secretory granules with a diameter of 250-350 nm. The findings promote the existence of a local paracrine system of the inner ear.

Adolescent↗
PubMed1985

Role of endogenous prostaglandins in somatostatin-induced inhibition of gastrointestinal hormone secretion.

Endogenous prostaglandins have been reported to be essential for the inhibitory effect of somatostatin on acid secretion. From these results it could be suggested that the effect of somatostatin on the secretion of gastroentero-pancreatic hormones may also be medulated by prostaglandins. This hypothesis was investigated in man and in the rat. Somatostatin-induced inhibition of postprandial gastrin, cholecystokinin, pancreatic polypeptide, and insulin release was not influenced by indomethacin pretreatment in healthy subjects. Using the isolated perfused rat stomach preparation, inhibition of acetylcholine-stimulated gastrin secretion by somatostatin was found to be unchanged by indomethacin treatment. It is concluded that endogenous prostaglandins are unlikely to be indispensable for the inhibitory effect of somatostatin on gastroentero-pancreatic endocrine cells.

Adult↗
PubMed1985

[Effect of osmolality on the gastrointestinal permeation of various carbohydrates in healthy persons].

The effect of a high osmotic solution on active and passive sugar permeation was investigated in 19 healthy volunteers. The reduced rate of active sugar absorption (3-O-MG and xylose) out of a high osmotic solution was interpreted as a consequence of an impaired emptying of the stomach. The increased passive permeation of intact disaccharides applied in hyperosmolar solution demonstrates an increased gastrointestinal permeability. Intubation studies suppose increased disaccharide absorption out of hyperosmolar solution in the stomach, i.e. high osmolar solutions increase gastric mucosal permeability.

3-O-Methylglucose↗
PubMed1984

[Bone marrow transplantation in panmyelopathy, acute leukemia and chronic myelocytic leukemia: results of the Ulm Transplantation Group].

From 1972-1983 53 patients underwent bone marrow transplantation. The median age was 18 years (3-41). 27 patients suffered from severe aplastic anaemia, 22 patients had acute leukaemia and 4 patients had chronic granulocytic leukaemia in chronic phase. Out of 22 patients with acute leukaemia, 2 had florid leukaemia, 2 had an early relapse and 18 patients were in first or second remission of their disease. 2/53 patients received a syngeneic transplant, 51/53 patients an allogeneic transplant. 47/51 patients had a HLA-A, B, C-identical, MLC-negative sibling donor, 1/51 had a HLA-A, B-C-identical, MLC-positive sibling donor, 2/51 a HLA-phaenotypical identical parental donor and 1/51 a HLA-identical, MLC-negative unrelated donor. The comparison of the results obtained in patients with severe aplastic anaemia transplanted from 1972-1979 with those transplanted from 1980-1983 shows that the bone marrow transplantation has to be performed in an early stage of the disease before the patients become multiple transfused, sensitized and severely infected and that the conditioning regimen for polytransfused patients has to be more intensive than in untransfused patients. From the patient group transplanted 1972-1979, only 1/14 patients is a long-term survivor in contrast to 8/13 patients transplanted from 1980-1983. 11/22 patients with acute leukaemia are alive between more than 5 years and 14 days after bone marrow transplantation. Only 1/4 patients, who were transplanted not in remission, is alive.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1984

General and selective inhibition of pancreatic enzyme discharge using a proteinase inhibitor (FOY-305).

The guanidino acid esters (FOY, FOY-305) represent a new class of potent proteinase inhibitors and are thought to have a beneficial effect on the course of acute pancreatitis. Because of their structure and low molecular size they might enter cells and interfere with cellular processes. To test this possibility in the case of the exocrine pancreas a series of in vivo and in vitro studies was carried out to analyse intracellular transport and discharge of pancreatic enzymes in the presence of FOY-305. The infusion of FOY-305 to conscious rats led to a transient inhibition of protein and enzyme discharge from the cannulated pancreas accompanied by lower serum enzyme levels and increased enzyme content in the pancreas. An identical inhibition of discharge of newly synthesized proteins was observed in vitro in the presence of 1 microM FOY-305. The analysis of the release of individual enzymes using separation on two-dimensional gels showed a pronounced inhibition of mainly the release of acidic proteins. FOY-305 not only interfered with discharge of serine proteinases (trypsinogen, chymotrypsinogen, proelastase) but also with procarboxypeptidases and lipase. It was concluded that FOY-305 enters the acinar cell and due to an unspecific binding to acidic proteins interferes with the intracellular transport of individual enzyme proteins during their passage through the membrane-bound cellular compartments. This charge-dependent effect is independent of the inhibitory effect on enzymatic activity of serine proteinases.

Amylases↗
PubMed1984

[Bezafibrate-induced myolysis and myoglobinuria in patients with impaired renal function].

A muscular syndrome has been described in patients on clofibrate and fenofibrate therapy. The present paper describes four patients with impaired renal function in whom symptoms and signs of skeletal muscle damage developed during treatment with another clofibrinic acid derivative, bezafibrate. The syndrome was characterized by variable degrees of muscular cramps and paresis, excessive elevation of muscle enzymes in serum, myoglobinemia and myoglobinuria. Transient deterioration of renal function was also common. All patients had been overdosed with bezafibrate with regard to their renal function. It is concluded that bezafibrate like other lipid lowering agents of the clofibrate type may induce muscle damage, at least if doses are not adjusted to renal function. Extreme caution is warranted when treating patients with renal impairment with bezafibrate and strict dose adjustment to kidney function is necessary to avoid muscle damage.

Aged↗
PubMed1984

[Ulcer hemorrhage--when operative hemostasis?].

Considering natural history, epidemiology and prognostic criteria bleeding peptic ulcers should be operated: 1) in case of active "uncontrolled" bleeding: emergency operation. If bleeding is controlled by laser coagulation or sclerotherapy: early-elective operation. 2) in case of capillary persistent bleeding, blood loss of more than 2500 ml/24 h or continuous bleeding after 48 h: early-elective operation.

Duodenal Ulcer↗
PubMed1984

Serotoninergic control of somatostatin and gastrin release from the isolated rat stomach.

The influence of exogenous serotonin on the secretion of gastric somatostatin and gastrin was investigated under in vitro conditions using an isolated, vascularly perfused rat stomach preparation. Serotonin stimulated gastrin release, maximal effects were observed at 10(-6) M which increased gastrin levels by 78%; on the contrary, somatostatin secretion was inhibited (maximal inhibition of 56% at 10(-6) M). Changes in hormone secretion in response to serotonin were reversed by combined blockade of 5-HT1 and 5-HT2 receptors by methysergide and blockade of 5-HT2 receptors by ketanserin (10(-5) and 10(-6) M, respectively), and of cholinoreceptors by atropine (10(-5) M). It is concluded that in rats in vitro serotonin inhibits release of gastric somatostatin and stimulates gastrin secretion via specific serotonin receptors but muscarinic cholinergic receptors are also involved.

Animals↗
PubMed1984

Asystole in the prolonged QT syndrome.

We report a 4 1/2 year old boy with the Romano-Ward syndrome in whom an asystolic period of 18 seconds duration followed an episode of ventricular tachycardia. Treatment with propranolol and implantation of a demand pacemaker has prevented further attacks.

Arrhythmias, Cardiac↗
PubMed1984

Fate of infants with transposition of the great arteries in relation to balloon atrial septostomy.

The palliation afforded by balloon atrial septostomy to 124 infants with transposition of the great arteries was assessed in terms of survival to 6 months of age without the need for further intervention. Prediction of success or failure in relation to palliation was significantly affected by the presence of associated ventricular septal defect, left ventricular outflow tract obstruction, or persistent ductus arteriosus and by the maximum volume of balloon used to perform the septostomy. There was a significant association between balloon volume and size of atrial defect found at subsequent surgery or necropsy.

Ductus Arteriosus, Patent↗
PubMed1984

Pancreatic polypeptide and gastrin release during sham feeding in man.

During modified sham feeding (MSF) the role of endogenous gastric acid secretion and the influences of the autonomic nervous system on the release of pancreatic polypeptide (PP) and gastrin have been studied in 12 healthy subjects (aged 24-38 years). Sham feeding was performed without pretreatment (control) and after pretreatment with 400 mg cimetidine, 80 mg propranolol (both given orally) or 1 mg atropine administered subcutaneously 60 min prior to sham feeding. MSF induced a significant increase (about 100%) in PP release. Its early peak was reduced by pretreatment with propranolol whereas cimetidine had no effect. Atropine completely abolished the PP response. Gastrin release was stimulated by MSF only after prior administration of cimetidine and, to a lesser extent, after atropine pretreatment. It is concluded that: (1) the PP release after stimulation is under strong cholinergic control but is also mediated--particularly in the early phase--by adrenergic mechanisms; (2) endogenously released acid during vagal stimulation plays a minor role in the modulation of PP secretion, but (3) masks gastrin response to MSF.

Adult↗
PubMed1984

Evaluation of serum pancreatic polypeptide estimations following hormonal stimulation for the diagnosis of exocrine pancreatic insufficiency.

Pancreatic polypeptide (PP) was measured in 74 patients with normal and in 42 patients with abnormal pancreatic function under fasting conditions (before and after duodenal intubation) and following secretin and cholecystokinin (CCK) stimulation. Fasting PP values of patients with severe but not with moderate exocrine pancreatic insufficiency were significantly lower than those of controls. Duodenal intubation led to a significant increase in fasting PP values. Both CCK and, to a lesser extent, secretin led to an increase in PP values. PP increase was significantly lower in patients with severe and not with moderate exocrine pancreatic insufficiency compared to controls following stimulation. Therefore, while fasting serum levels of PP and those following low stimulation indicate severe exocrine pancreatic insufficiency in the absence of previous vagotomy, PP estimations do not enable diagnosis of moderate functional impairment of the pancreas.

Adult↗