Search PubMed⌕ Search

Biomedical subjects

L Boquist

Publications and source records attributed to L Boquist.

At least 91 records · Page 5Linked to original sources
PubMed1978

Effect of metabolic alkalosis on the B-cell sensitivity to alloxan in vivo.

Metabolic alkalosis was induced in starved mice by treatment with NaHCO3, which did not significantly alter the blood glucose concentration, but protected against the diabetogenic effect of subsequently given alloxan. This protection and the alkalosis had disappeared 4 hr after NaHCO3 treatment. Protection against alloxan, and metabolic alkalosis, were found also in starved mice pretreated with sodium lactate. The findings indicate that metabolic alkalosis, directly or indirectly, protects against alloxan toxicity in vivo.

Alkalosis↗
PubMed1978

Osteosarcoma. A multifactorial clinical and histopathological study with special regard to therapy and survival.

A multifactorial analysis was performed on all 153 unequivocal cases of genuine osteosarcoma recorded in the Swedish Cancer Registry for the years 1958 through 1968. Cases of so-called parosteal osteosarcoma, soft-tissue osteosarcoma and osteosarcoma secondary to Paget's disease of bone were not included. The osteosarcomas were subclassified as follows: osteoblastic (69 per cent), chondroblastic (19 per cent) and fibroblastic (12 per cent). The overall 5-year survival rate was 22 per cent; 55 per cent for those who had undergone amputation above the joint proximal to the involved skeletal part, 22 per cent for those amputated on the involved skeletal part, 11 per cent for those treated with local extirpation of the tumor, and 1 per cent in cases in which the lesion was not radically removed. Tumors of the femur, humerus and scapula were as malignant as axial tumors. The former carried a 5-year survival rate of 13 per cent, regardless of whether the patients had been treated with exarticulation or amputation on the involved skeletal part. Patients with axial tumors showed a 5-year survival rate of 15 per cent. These survival data suggest that proximal amputation alone might suffice for lesions situated distally to the knee and elbow joints, while tumors in the humerus and femur should be treated with amputation combined with multicytostatic treatment or immunotherapy and axial tumors with local resection and multicytostatic or immunologic treatment.

Adolescent↗
PubMed1978

Telangiectatic osteosarcoma.

Of the 242 cases of osteosarcoma recorded in the Swedish Cancer Registry for the years 1958 through 1968 only one was found to represent telangiectatic osteosarcoma. Another case was recently diagnosed in our department. The characteristic morphologic features of these neoplasms were anaplastic stroma, high mitotic activity, osteoid-formation, widely anastomosing blood spaces, and alkaline phosphatase activity. The experience gathered indicates that telangiectatic osteosarcoma constitutes a histopathologic variant of genuine osteosarcoma with a serious prognosis, necessitating the same kind of treatment as for the genuine tumour.

Adolescent↗
PubMed1978

Giant serpentine intracranial aneurysm after carotid ligation. Case report.

A case is reported of a giant aneursym of the intracavernous portion of the left internal carotid artery that was treated initially with a left common carotid artery ligation. Six months later the aneurysm was partially removed. During this time the development and evolution of thrombus formation, a serpentine channel, and a hypervascular capsule was easily followed with recreated computerized tomography and angiography of the aneurysm.

Adult↗
PubMed1978

Factors affecting the beta-cell sensitivity to alloxan in vivo. Influence of pre- and post-treatment with protective substances.

Blood glucose and pancreatic islet morphology were studied in mice subjected to different kinds of treatment both before and after alloxan administration. d-Glucose, d-mannose, d-fructose, NaHCO3 and sodium lactate protected against alloxan when given before, but not when given after alloxan, whereas l-leucine protected when administered before, and also when injected 1 or 3 min after alloxan. No protection was seen in animals receiving l-leucine 10 min following alloxan. The findings may indicate that the mechanism for alloxan protection by l-leucine differs from that of the other compounds tested.

Alloxan↗
PubMed1978

Pancreatic B-cell sensitivity to alloxan in vivo. A study of antagonizing compounds, serum inorganic phosphate and acid-base balance.

Serum glucose, inorganic phosphate, acid-base balance and islet morphology were studied in mice subjected to different kinds of treatment before alloxan administration. In preceding studies, pretreatment with D-glucose, D-mannose, D-fructose, sodium lactate and NaHCO3, but not with D-galactose, was found to protect against alloxan toxicity. In this study alloxan antagonism was found by pre-treatment with L-leucine, but not with L-arginine or NaH2PO4. Blood analyses, carried out 10 minutes after injection of the test compounds, disclosed that the serum inorganic phosphate concentration was decreased in mice given D-glucose, D-mannose, D-fructose, sodium lactate, NaHCO3, L-leucine, and L-arginine, but was not affected in those treated with D-galactose, and was increased in those receiving NaH2PO4. With the exception of L-arginine, blood pH was increased in the groups which exhibited decreased serum inorganic phosphate concentration; pH was not affected in mice treated with D-galactose, L-arginine and NaH2PO4. Alterations in inorganic phosphate and hydrogen ion concentration may affect the B-cell sensitivity to alloxan ("Pi-pH hypothesis").

Acid-Base Imbalance↗
PubMed1977

Pancreatic islets subjected to different concentrations of glucose in vitro. A study with special regard to mitochondrial changes.

Isolated pancreatic islets of mice and gerbils were cultured for 6 days at low (2mM) or high (20mM) concentrations of glucose after which they were studied using qualitative and quantitative electron microscopy, histo- and microchemistry, and X-ray microanalysis. Compared with the islets cultured at high glucose, those subjected to low glucose exhibited enhanced succinate dehydrogenase activity, a decreased content of adenosine triphosphate, and an increased volume of B-cell mitochondria which often were rounded or oval.

Adenosine Triphosphate↗
PubMed1977

Ultrastructural changes in the parathyroids of Mongolian gerbils induced experimentally in vitro. Effects of variations in Ca2+ and Mg2+ concentrations.

Isolated parathyroid glands from normal adult Mongolian gerbils were incubated for 15 minutes to 3 1/2 hours either at high or low concentrations of Ca2+ and Mg2+ after which they were studied ultrastructurally, using the pyroantimonate technique and x-ray analysis for identification and son concentrations were mainly composed of suppressed chief cells with moderate or high cytoplasmic density, sparsely developed endoplasmic reticulum, often large Golgi complex, occassional cytoplasmic accumulations of secretory granules, lipoid bodies, glycogen-like particles, and numerous often large mitochondria. Ca2+-containing precipitates were found mainly in mitochondria. Autophagic vacuoles contained Ca2+-loaded degenerating mitochondria. Glands exposed to low concentrations of Ca2+ and Mg2+ were mainly composed of stimulated and active chief cells; characteristic features were a moderate or low cytoplasmic density, prominent endoplasmic reticulum, small Golgi complex, medium-sized, or small mitochondria, and smooth electron lucent vacuoles with or without an association of mitochondria. Ca2+-containing precipitates were found mainly in smooth vacuoles and cytosol, but also in mitochondria and routh vacuoles. Myelin-like figures and crystalloid bodies occurred in some mitochondria, and normal or degenerating mitochondria withoug Ca2+-loading were seen in autophagic vacuoles. In addition, some stimulated chief cells exhibited double membrane-limited sequestered areas of cytoplasm with a rich content of free ribosomes and glycogen-like particles. The chief cell mitochondria seem to possess capacity for rapid accumulation of Ca2+, associated with an increase in volume at functional suppression. At stimulation of parathyroid function the endoplasmic reticulum is prominent in the active cells, and there seems to be a decrease in the volume and Ca2+-content of the mitochondria occasionally associated with degenerative changes, and a decrease also in the number of free ribosomes and glycogen-like particles in the stimulated cells.

Animals↗
PubMed1977

The effect of immunotherapy with BCG on the development of radiostrontium (90Sr)-induced osteosarcoma.

The development of radiostrontium-induced osteosarcoma was studied in BCG-treated and in untreated control mice. Within the observation period of 420 days after the administration of radiostrontium there was a total tumour-incidence of 89.5 and 90.5 per cent for the respective groups of animals. There was no statistically significant difference between the two groups, neither with regard to the time of the first roentgenographic appearance of the osteosarcoma, nor concerning the total tumour incidence , nor with regard to the distribution of the primary sites of the tumours. The tumours of the BCG-treated animals showed a clear tendency to a slower growth rate in comparison to that of the tumours in the control animals. This effect was probably immunological in nature. The mortality in osteosarcoma following radiostrontium administration, however, showed no significant difference between the two groups. Light microscopical and ultrastructural examination did not disclose any clear structural difference between the tumours from BCG-treated and untreated control animals.

Animals↗
PubMed1977

Effect of 1.25-dihydroxycholecalciferol administration on blood glucose and pancreatic islet morphology in mice.

1.25-dihydroxycholecalciferol (DHCC) administration to fed and starved mice had no effect on the blood-glucose concentration or the light-microscopic appearance of the endocrine or exocrine pancreas. Electron microscopy, however, disclosed changes which appeared early after the injection and were more marked in starved than in fed animals. The B-cells exhibited mitochondrial hypertrophy, studied both by qualitative and quantitative methods, invagination and vacuolation of mitochondrial membranes, increased occurrence of light secretory granules, multiple rough endoplasmic cisternae, multi-lamellar bodies, and a rather rich Ca2+-containing pyroantimonate precipitation mainly localized to nuclei and mitochondria. A tendency to mitochondrial hypertrophy was observed also in some D-cells. The A-cells were unaffected. The findings indicate that the endocrine pancreas (or at least the B-cells) is affected in some way, directly or indirectly, by DHCC.

Animals↗
PubMed1977

Effects of 1.25-dihydroxycholecalciferol, parathormone and Ca2+ on the pancreatic B-cell sensitivity to alloxan.

The sensitivity to alloxan was investigated by blood and urine glucose determination and light and electron microscopic study of the endocrine pancreas in groups of mice differing from each other with respect to food ingestion and treatment before alloxan administration. Because of differences in occurrence of glucosuria, degree and duration of hyperglycemia, and severity of structural lesions, it was concluded that starvation increases the alloxan sensitivity and that pre-treatment with 1.25-dihydroxycholecalciferol (DHCC) or parathormone (PTH), but not with Ca2+, enhances the alloxan effect. The serum-calcium concentration determined 10 minutes after pre-treatment was significantly increased in the group given Ca2+, but not in the groups injected with DHCC or PTH. Starved mice injected with DHCC or PTH 10 minutes before alloxan administration exhibited a pronounced second hyperglycemia of long duration, and extensive, selective B-cell necrosis. Starvation and increased serum concentration of DHCC and PTH are believed, directly or indirectly, to induce B-cell alterations which increase the alloxan sensitivity.

Alloxan↗
PubMed1977

Angiography in giant-cell tumours of bone.

The angiographic appearance of 9 cases of genuine giant-cell tumour of bone, 6 cases of aneurysmal bone cyst and one case of non-ossifying fibroma is described. Differential diagnosis would appear to be possible to a certain extent. The non-ossifying fibroma was poorly vascularized. The genuine giant-cell tumours were hypervascularized as well as some of the aneurysmal bone cysts making a differential diagnosis in these cases impossible. On the other hand, a poorly vascularized tumour devoid of soft tissue component and arteriovenous fistulas is probably an aneurysmal bone cyst. A hypervascular soft tissue component is of great prognostic value in cases of geniune giant-cell tumour.

Angiography↗
PubMed1977

The endocrine pancreas in early alloxan diabetes. Including study of the alloxan inhibitory effect of feeding and some hexoses.

Starved animals were sensitive to alloxan, whereas a more or less inhibitory effect towards alloxan was observed in fed animals, and in starved animals pretreated with glucose, mannose or fructose, but not in those pretreated with galactose. The islets of starved controls possessed larger B-cell mitochondria than those of fed ones. The earliest B-cell changes in the alloxan-treated animals were localized to the mitochondria which showed swelling, and disruption of inner and occasionally outer membranes. Later, many mitochondria were disintegrated, and the endoplasmic reticulum and Golgi complex disorganized. The secretory granules were preserved, although sometimes with atypical configuration, in degenerating but non-necrotic B-cells, suggesting that insulin stored in granules is not released until the cells are necrotic. Finally, frank necrosis was seen in some B-cells, whereas others were unaffected. The Ca2+-precipitation studied by pyroantimonate technique and x-ray analysis differed in the B-cells of the alloxan-treated animals from that in the controls; the former animals exhibited no or only sparse precipitation in mitochondria and secretory granules, but a rich precipitation in the cytoplasmic ground substance, whereas the precipitation in the controls mainly was localized to mitochondria and secretory granules. The primary site of alloxan action in the B-cells is believed to be localized to the mitochondria.

Animals↗
PubMed1977

Thyroid carcinoma in children.

A study was made of 24 children under 15 years with thyroid cancer diagnosed during the years 1959-1967. None of the children had received irradiation treatment prior to diagnosis. Treatment took the form of surgery in combination with hormone and/or irradiation therapy. Of the 24 patients, only one died as a result of postoperative complications, even though 17% had lung metastases and 58% lymph gland metastases. The children were observed on average seven years, 10 months and the longest period of observation was 12 years, six months. The treatment recommended is total lobectomy on the affected side and subtotal on the opposite side. Cervical lymph glands with metastases are extirpated. Thyroid hormone treatment should be given immediately after surgery.

Adenocarcinoma↗
PubMed1977

Low doses of 1,25-dihydroxycholecalciferol increase mature bone mass in adult normal rats.

Low doses of 1,25-DHCC cause a significant increase in trabecular and cortical bone mass of the mature rat skeleton by stimulated endosteal bone formation. The increased serum contents of calcium and inorganic phosphate give rise to a moderate nephrocalcinosis. An increased bone resorption occurs upon toxic dose levels causing profound nephrocalcinosis. Similar doses of 25-HCC do not affect the mature bone.

Animals↗
PubMed1976

Primary carcinoma of the appendix.

Primary adenocarcinoma of the appendix is rare and less than 200 cases are on record. The present material consisted of 20 cases collected from different hospitals. The cases are described in respect of sex and age-distribution, symptoms, treatment and prognosis. Of 7 patients with malignant mucocele, 6 subjected to appendectomy only, were still alive 5 years after the operation. Of 12 patients with colonic type of adenocarcinoma, 3 had been treated with appendectomy only. Of these, 2 were still alive 5 years after the operation. The remaining 9 patients had undergone right hemicolectomy. Only one of them was alive 5 years after the operation. A compilation of a further 39 cases garnered from the literature, however, showed that 60% had survived at least 5 years after right hemicolectomy, compared with 46% after appendectomy alone. Appendectomy alone is probably a sufficiently radical operation for malignant mucocele provided the tumor has not grown through the submucosa and that it is confined to the tip of the appendix. Right hemicolectomy is indicated for the colonic type of adenocarcinoma.

Adenocarcinoma↗