726
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Donoghue S, Garcia M, Jordan D, Spyer KM. Identification and brain-stem projections of aortic baroreceptor afferent neurones in nodose ganglia of cats and rabbits. J Physiol 1982; 322:337-52. [PMID: 7069619 PMCID: PMC1249673 DOI: 10.1113/jphysiol.1982.sp014040] [Citation(s) in RCA: 76] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
1. The retrograde transport of horseradish peroxidase (HRP) was used to locate cell bodies of afferent neurones with axons in the aortic nerves within the nodose ganglia of cats and rabbits. 2. In the rabbit HRP-labelled cells were localized to the medial aspect of the ganglion in the vicinity of the entry of the superior laryngeal and aortic nerves. 3. A similar grouping of labelled cells in rostro-medial aspects of the ganglion was seen in the cat, though there were many other labelled cells distributed throughout the ganglion. It is suggested that the former cells may be barosensory and the latter chemosensory. 4. Extracellular recordings were made from baroreceptor afferents in the nodose ganglia of rabbits and cats using glass micro-electrodes. Recordings sites were confined to rostral regions of the ganglia. 5. The projections of single baroreceptor afferents were studied by antidromic activation from the medulla oblongata using electrical stimulation applied through tungsten--glass micro-electrodes. Evidence is presented on the basis of depth--threshold contours and antidromic latency which indicates that stimulation of the main axons can be distinguished from stimulation in areas of branching and presumed termination. 6. In cats aortic baroreceptor afferents gave branches to either medial (three out of six) or lateral (three out of six) subnuclei of the nucleus tractus solitarius (n.t.s.). One neurone had additional projections to the contralateral medial subnuclei of the n.t.s. 7. In rabbits the afferents have branches mainly to lateral subnuclei of the n.t.s. (seven out of eight neurones) with only one giving branches to the medial subnucleus of the n.t.s. and additionally to the nucleus alaris. 8. Projections to the medulla extending beyond the immediate vicinity of the n.t.s. were found in either species.
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727
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Morata P, Vargas AM, Sánchez-Medina F, Garcia M, Cardenete G, Zamora S. Evolution of gluconeogenic enzyme activities during starvation in liver and kidney of the rainbow trout (Salmo gairdneri). COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1982; 71:65-70. [PMID: 7060358 DOI: 10.1016/0305-0491(82)90176-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
1. There was a general increase in the activities of enzymes involved in gluconeogenesis in liver and kidney of rainbow trout, Salmo gairdneri, during the second month of starvation. 2. The need of gluconeogenesis during the first month of the starvation period was probably minimal because of the utilization of liver glycogen as a source of blood glucose. 3. The decline of fat was more pronounced than that of protein total content in absolute values, suggesting that lipid reserved were the main sources of energy during starvation.
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728
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Sanz A, Garcia M, Cardenete G, Zamora S. Hepatectomy in rainbow trout (Salmo gairdneri). A preliminary study. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. A, COMPARATIVE PHYSIOLOGY 1982; 71:329-32. [PMID: 6121656 DOI: 10.1016/0300-9629(82)90410-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
1. Partial hepatectomy (25% of liver mass removed) has been performed on rainbow trout using a procedure allowing a high level of survival. 2. The liver regeneration was complete from the point of view of liver weight, at the 30th post-operative day. 3. During the first weeks after surgery, the NH-excretion rate in both hepatectomized and shamoperated trout was higher than in intact controls. Likewise, the food intake was lower in the operated animals. 4. Both facts can be attribute to the stress situation caused by the surgical manipulations rather than the removal of the liver.
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729
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Adams J, Garcia M, Rochefort H. Estrogenic effects of physiological concentrations of 5-androstene-3 beta, 17 beta-diol and its metabolism in MCF7 human breast cancer cells. Cancer Res 1981; 41:4720-6. [PMID: 6458355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
5-Androstene-3 beta, 17 beta-diol (ADIOL) has previously been shown to have a high affinity for the estrogen receptor and to translocate it to the nucleus in vitro and in vivo. This compound and related C19 delta 5-steroids of adrenal origin have now been examined for their ability to induce the synthesis in MCF7 cells of an estrogen-dependent secreted glycoprotein (M.W. 46,000). Concentrations required for half-maximum induction were 2 nM for ADIOL and 500 nM for dehydroepiandrosterone (DHEA). Dehydroepiandrosterone sulfate showed weak inducing ability at concentrations of 1 microM or greater. The induction by ADIOL was unaffected by the presence of an aromatase inhibitor, and 5 alpha-androstane-3 beta, 17 beta-diol, which cannot be aromatized, also induced the M.W. 46,000 protein at low concentrations. When cells were exposed to 10 nM [3H]ADIOL, the cytosol and nuclear fractions contained [3H]ADIOL resistant to charcoal adsorption. The bound [3H]ADIOL in the cytosol and nucleus was displaceable by 17 beta-estradiol and tamoxifen, suggesting that it was binding to the estrogen receptor. [3H]ADIOL was metabolized to its 3 beta-sulfate, which was excreted into the medium, and to [3H]DHEA, which was found in the cells and the medium as free DHEA and its 3 beta-sulfate. [3H]DHEA was also metabolized by the cells to its 3 beta-sulfate, to free ADIOL, and to the 3 beta-sulfate of adiol. We conclude that: (a) ADIOL is effective as an estrogen in MCF7 cells at a concentration of 2 nM, which is within the range found in the blood of normal women; and (b) sulfurylation is a major route of inactivation of 3 beta-hydroxy delta 5-steroids in MCF7 cells.
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730
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Sommer T, Kantartzis M, Garcia M, Schubert GE. [Pleural metastases can simulate a mesothelioma]. MEDIZINISCHE KLINIK 1981; 76:626-629. [PMID: 6273705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We are reporting about an inoperable cell carcinoma of the stomach, which exclusively caused thoracal pains due to metastases into a pleural thickening. First this symptomatology with thoracal pains and recurring pleural effusions was thought to be a pleural mesothelioma. Only the immediate histological examination of the tissue showed the origin of the tumor. Although cancer of stomach appears very commonly, this tumor is often diagnosed too late and in most cases it is already inoperable. Even nowadays more than 75% of the patients with a cancer of the stomach die of their metastases, although diagnosis and therapy have been developed. - Pleural mesotheliomas are rare; nevertheless the possibility of a mesothelioma in connection with all pleural effusions of a vague genesis should be considered. The exposure to asbestos strengthens the suspicion that this tumor is existing. In connection with a pleural mesothelioma an indurative pleurisy, a primary cancer of the lung and - like in our case - pleural metastases of a primary cancer of another site have to be differentiated.
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731
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Vignon F, Capony F, Garcia M, Veith F, Westley B, Rochefort H. [Oestrogen-induced proteins in breast cancer (author's transl)]. ANNALES D'ENDOCRINOLOGIE 1981; 42:327-32. [PMID: 7200344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The hormone dependence and the prognosis of human breast cancers are currently based on assays of the estrogen receptor (RE) and progesterone receptor (RP) in the tumor. However, such prediction can not be fully accurate: RE may be non functional in some tumors and the estrogenic regulation of RP is not directly correlated with the effects of estrogens on cell growth. Here we described other estrogen induced intracellular, secreted or membrane proteins. Investigations of these proteins should allow a better understanding of the mechanisms by which estrogens stimulate the growth and spreading of breast cancer. Some secreted proteins could even be useful as circulatory markers of hormone dependence.
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732
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Warshal D, Jacobs M, Lee W, Garcia M. A portable feedback gait apparatus for five segments of footfall. Phys Ther 1981; 61:1454-6. [PMID: 7280028 DOI: 10.1093/ptj/61.10.1454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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733
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Lemus D, Illanes J, Fuenzalida M, De La Vega YP, Garcia M. Comparative analysis of the development of the lizard,Liolaemus tenuis tenuis. II. A series of normal postlaying stages in embryonic development. J Morphol 1981; 169:337-349. [DOI: 10.1002/jmor.1051690307] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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734
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Garcia M, Lee M. Interaction of cadmium and zinc during prenatal development in the rat. Biol Trace Elem Res 1981; 3:149-56. [PMID: 24271752 DOI: 10.1007/bf02990113] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/1980] [Accepted: 03/03/1981] [Indexed: 10/21/2022]
Abstract
Cadmium chloride, zinc chloride, or a mixture of the two, labeled with 115m-Cd or 65-Zn was administered intraperitoneally to Wistar rats on day 9 of gestation. On day 20 fetuses of Cd-treated rats exhibited malformations, but those of rats given zinc or zinc plus cadmium did not. No radioactive cadmium was recovered in the fetuses or fetal membranes, although some was found in the placentas. Simultaneous administration of zinc did not alter the distribution of cadmium, but cadmium significantly increased the amount of zinc in the fetus and placenta. In a second experiment, cadmium or cadmium plus zinc was administered on day 9 of gestation and embryonic units were removed on days 10, 11, and 12. On day 10 cadmium was found in the embryonic unit and maternal uterus, and cadmium in both was significantly reduced by simultaneous administration of zinc. The cadmium concentration in uterus and embryonic units decreased sharply on day 11 and 12 and by day 12 did not differ in animals treated with cadmium or with cadmium plus zinc. It is concluded that cadmium reaches the placenta or embryo at an organogenetically sensitive time, and that zinc may protect the embryo by decreasing the exposure to cadmium this time.
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735
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Garcia M, Westley B, Rochefort H. 5-Bromodeoxyuridine specifically inhibits the synthesis of estrogen-induced proteins in MCF7 cells. EUROPEAN JOURNAL OF BIOCHEMISTRY 1981; 116:297-301. [PMID: 7250129 DOI: 10.1111/j.1432-1033.1981.tb05333.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
In the MCF7 human breast cancer cell line, estrogens induce a secreted glycoprotein with an Mr of 46 000 (46 000-Mr protein) and the progesterone receptor; they also increase to a lesser extent the secretion of [35S]-methionine-labelled proteins. When the cells are grown in the presence of 5-bromo-2'-deoxyuridine (BrdUrd, 5 microgram/ml for 4 days) these estrogen-induced responses are substantially inhibited while other proteins not regulated by estrogens and cell growth are not affected by BrdUrd. This effect of BrdUrd is not secondary to a decrease in estrogen receptor levels and appears to require incorporation of BrdUrd into DNA for the following reasons. First, there is a lag before any effect of BrdUrd is seen which is similar to the doubling time of the cells. Second, the effect of BrdUrd is not seen when cells are cultured in medium containing BrdUrd and 1-beta-D-arabinofuranosylcytosine, a DNA synthesis inhibitor, or excess thymidine, which blocks the incorporation of BrdUrd into DNA. Finally 2'-deoxycytidine, which reverses the effects of non-incorporated BrdUrd, is without effect on the inhibition of the estrogen-induced 46 000-Mr protein. We conclude that BrdUrd selectively prevents the effects of estrogens in MCF7 cells and that the mechanism of this anti-estrogenic effect of BrdUrd probably requires its incorporation into DNA and occurs beyond the nuclear translocation step of the estrogen receptor. Alterations in the recognition of chromatin effector sites by the estrogen-receptor complex could be involved in preventing hormone action.
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736
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Botey A, Garcia M, Revert L. [Essential hypertension and diabetes]. Med Clin (Barc) 1981; 76:145-9. [PMID: 7010018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Exchangeable sodium (E-Na), plasma volume (PV), and plasma renin activity (PRA) have been studied in 19 patients with essential hypertension and diabetes, and the results compared to those of non-diabetic patients with benign essential hypertension. None of the cases had renal disease or hypertension with systolic predominance. E-Na was 114 +/- 9.74 (SD), significantly superior to that of normal subjects (p less than 0.001). An elevated E-Na was observed in 52.6% of the diabetic group, while PV was normal. PRA levels were normal in most patients, mean 1.28 +/- 1.97 ng ml-1 h-1, only two patients disclosing an elevated PRA (10.5%). No relationship was found between PRA and age, blood pressure, and E-Na. From the comparison of results between diabetic and non-diabetic hypertension patients it appears that: 1) no differences between mean PRA and E-NA exist, although a greater percentage of diabetics have an elevated E-Na, and 2) in the non-diabetic group there is a positive correlation between E-NA and PV, while in the diabetic group such a correlation is negative (p less than 0.05). The finding of an elevated body sodium in patients with essential hypertension and diabetes probably represents a true abnormality in the body composition of these patients, although there is no explanation for the fact that it is unassociated to an increase of the plasma volume, as opposed to essential hypertension in non-diabetics.
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737
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Abstract
A 51 year old nurse had a long complicated medical history with repeated medical and surgical interventions. Her condition fits the clinical description of the Münchausen syndrome. She presented to the hospital with hyperabsorptive hypercalcemia of over 20 mg/100 ml. Many diagnostic studies and intriguing detective investigations were undertaken before the cause of the extreme hypercalcemia was determined. The patient had been secretly ingesting between 20 and 30 Os-Cal 500 tablets daily which she repeatedly denied and which eventually were found in a false compartment of her purse. This is thought to be the highest recorded serum calcium level observed following the clandestine ingestion of excessive amounts of oral calcium.
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738
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Sanchis Fargueta J, Iranzo R, Garcia M, Jorda M. Hemangioma calcificans--a benign epileptogenic lesion. SURGICAL NEUROLOGY 1981; 15:66-70. [PMID: 7256529 DOI: 10.1016/s0090-3019(81)80093-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Hemangioma calcificans is a rare condition that may be regarded as a calcified cerebral cavernous angioma. The clinical presentation is usually that of epilepsy in an adult. A calcified nodule is visible on radiographs of the skull or computed tomographic (CT) scans. Angiography does not demonstrate vascularity. It is usually a solitary subcortical lesion that is surgically removable. Because of the favorable results from treatment of this lesion, this report reviews the clinical and radiological features described in the literature and includes an additional case.
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739
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Garcia M, Zamora S, Lopez M. The influence of partial replacement of protein by fat in the diet on protein utilization by the rainbow trout (Salmo gairdnerii). ACTA ACUST UNITED AC 1981. [DOI: 10.1016/0305-0491(81)90155-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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740
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741
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Vic P, Garcia M, Humeau C, Rochefort H. Early effect of estrogen on chromatin ultrastructure in endometrial nuclei. Mol Cell Endocrinol 1980; 19:79-92. [PMID: 7390003 DOI: 10.1016/0303-7207(80)90032-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The effect of estradiol on chromatin ultrastructure in interphase nuclei was studied in immature rat and lamb endometrium. Physiological doses of estradiol within the first hour transformed the condensed chromatin into dispersed chromatin both in vivo and in vitro. These ultrastructural modifications were specifically induced by hormones translocating the estrogen receptor to the nucleus of estrogen-responsive tissues. Conversely, the antiestrogen tamoxifen gave a hypercondensation of chromatin. The addition of actinomycin D, cordycepin or alpha-amanitin, but not of cycloheximide, prevented the effect of estradiol both on the ultrastructural change and on [3H]uridine incorporation, suggesting that chromatin decondensation was closely related to transcriptional activity. These results indicate that in endometrium, estrogen rapidly provokes a large and extended modification of chromatin ultrastructure, which suggest a general effect on chromatin function rather than a selective activation of a limited number of genes.
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742
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Darnell A, Garcia M, Bergadá E, Revert L. [Long-term hemodialysis in acute barbiturate intoxication (author's transl)]. Med Clin (Barc) 1980; 75:49-53. [PMID: 7401733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
From 1975 to 1978, ten patients were on long-term hemodialysis due to acute barbiturate intoxication. Duration of hemodialysis varied from 16 to 40 hours (mean 23 +/- 9.4 hours). Phenobarbital was the most common type of barbiturate ingested (6 out of 10 patients), and diazepam the drug most frequently taken in association with barbiturates (3 out of 10 patients). All patients were in a state of deep unconsciousness (coma II: 1 case; coma III: 5 cases; coma IV: 4 cases), and all of them required endotracheal intubation. Seven patients needed the assistance of automatic intermittent positive-pressure respirator. Two patients presented hypothermia, and another a peripheral collapse. Long-term hemodialysis was well tolerated without major complications. Significant decreases of barbiturate levels were obtained in all cases (before hemodialysis: 7.3 +/- 1.9 mg/dl, after hemodialysis: 1.8 +/- 1.2 md/dl, corresponding to the pattern of secobarbital used to refer the results). No correlation was observed between initial levels of barbiturates and number of hours of long-term hemodialysis required. Neurologic symptoms improved in all cases. Eight patients were conscious after hemodialysis had been discontinued, and only two patients remained unconscious (coma I). Intratracheal tube could be removed in six patients, but positive-pressure respirator could be took away from all cases. Complete recovery was achieved in eight patients. Two patients died on the 2nd. and 8th. postdialysis days due to respiratory distress. Long-term hemodialysis has proven of value in the treatment of severe barbiturate intoxication, particularly better to conventional hemodialysis.
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743
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744
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Letsch R, Kantartzis M, Sommer T, Garcia M. Arterial fibromuscular dysplasia. Report of a case with involvement of the aorta and review of the literature. Thorac Cardiovasc Surg 1980; 28:206-10. [PMID: 6156517 DOI: 10.1055/s-2007-1022078] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A case of fibromuscular dysplasia (FMD) with involvement of the aorta is described in a 44-year-old woman. So far only 3 cases of aortal FMD have been mentioned, all in female patients. Our observation is characterized by a solitary stenosis of the lower abdominal aorta and it resembles histologically the "intimal fibroplasia" type of renal FMD. The review of the literature about FMD in general reveals that mostly the renal arteries are affected, followed by cervical artery FMD with only rare occurrence in other vessels. Though the etiology is basically unknown several factors have been made responsible, namely hereditary disposition, congenital rubella infection, female hormones, paucity of the vasa vasorum, and stretch-traction-stress. The disease has been classified into several histological subgroups and also according to the roentgenologic form which typically shows a "string of beads" appearance. There is a definitive female sex preponderance of 5:1, which is the same for all affected vessels; whereas in respect to age there is a marked distinction in so far that renal FMD patients on average are 11 years younger than patients with the cervicocephalic form of the disease.
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745
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Kantartzis M, Sommer T, Garcia M, Schubert GE. [Pulmonary harmatoma. Differential diagnosis and therapy]. DIE MEDIZINISCHE WELT 1980; 31:691-3. [PMID: 7421501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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746
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Abstract
In twelve patients with primary hyperparathyroidism the raised parathyroid hormone (PTH) levels consistently returned to normal with cimetidine ("Tagamet"), 300 mg four times a day, orally. As PTH levels returned to normal, signs and symptoms improved. Reduction of hypercalcaemia varied with the time, dose, and route of administration of cimetidine. Whenever cimetidine was discontinued, there was a rebound of PTH levels to approximately twice the initial value, which suggests that cimetidine blocks the synthesis and/or secretion of parathyroid hormone, so that parathyroid hormone or its precursor accumulates in the gland. A solitary parathyroid adenoma has been confirmed surgically in the five patients so far operated on. In all surgical patients the PTH levels were brought to normal by cimetidine preoperatively; these levels were maintained postoperatively. The adenomas were unusually large, firm, and congested; there was no atrophy of the rest of the glands. These last two observations further support our hypothesis that cimetidine blocks the synthesis or release of parathyroid hormone; they also support the concept that in primary hyperparathyroidism the parathyroid adenoma becomes autonomous or there is an abnormal hormone.
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747
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Le Menn F, Rochefort H, Garcia M. Effect of androgen mediated by the estrogen receptor of fish liver: vitellogenin accumulation. Steroids 1980; 35:315-28. [PMID: 6769182 DOI: 10.1016/0039-128x(80)90044-6] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
We have investigated the action of high doses of androgens in Gobius niger L., a marine teleostean fish, by characterizing specific steroid receptors in liver and by assaying the plasma vitellogenin concentration under different hormonal treatments. Estrogen and androgen receptors were characterized in the liver nuclear extracts according to their binding specificity. The maximum binding capacity was 25 fmoles/mg protein for the estrogen and androgen receptors. In vivo, high doses of DHT()increased the concentration of plasmatic vitellogenin as assayed by immunodiffusion while low doses were inefficient. In spite of a similar number of estrogen and androgen nuclear receptor sites (25 fmoles/mg protein), DHT was at least 70 fold less active than E2 on yolk protein and vitellogenin induction both in male and female Gobius niger. In addition, the antiestrogen tamoxifen, which was inactive by itself, inhibited the E2 and the DHT induced accumulation of vitellogenin. Progesterone (2 mg/fish) was also totally inactive in inducing vitellogenin. We conclude that the induction of vitellogenin by DHT is mediated by the estrogen receptor rather than by the androgen receptor. In addition to the estradiol induced protein in rat uterus and to other estrogenic responses obtained by androgens in mammary cancer, fish vitellogenin is another estrogen regulated protein which can be induced by high doses of androgens.
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748
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Rochefort H, Capony F, Garcia M. Mechanism of action of antiestrogens and androgens on the estrogen receptor. JOURNAL OF STEROID BIOCHEMISTRY 1979; 11:1635-8. [PMID: 574911 DOI: 10.1016/0022-4731(79)90361-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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749
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Garcia M, González R. [Effect of pyridoxine on histamine liberation and degranulation of rat mast cells]. Allergol Immunopathol (Madr) 1979; 7:427-32. [PMID: 94242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Pyridoxine, one of the B vitamins, has been shown to be useful in the treatment of childhood bronchial asthma by Collip et al. (1975). A double-blind study with 76 asthmatic children followed for five months indicated significant improvement in asthma following pyridoxine therapy (200 mg daily) and a reduction in dosage of bronchodilators and cortisone. Other reports have shown that nicotinamide, another B vitamin shows inhibitory activity in rat mast cell degranulation and histamine release (Bekier et al. 1974, Wiczolkowska and Maslinski, 1975, 1976). These results induced us to investigate if pyridoxine, like nicotinamide or disodium cromoglycate, exhibits pharmacological inhibitory activity in rat mast cell degranulation and histamine release induced by antigen or other non-immunological stimulants. We found that pyridoxine at concentrations of 10 (-3) M, or greater significantly inhibited rat mast cell degranulation and histamine release induced by phospholipase A, compound 48/80, antigen (egg albumin) or a mixture of dextran and phosphatidyl serine, respectively. In these experimental models, pyridoxine shows a pharmacological profile similar to nicotinamide and disodium cromoglycate, although weaker than the latter. In spite of this, the lack of toxicity of this vitamin at relatively high doses (1 or 1.5 g), the possibility that other mechanisms of action may be involved, such as the improvement in tryptophan metabolism reported by Collip following pyridoxine therapy, suggest that this vitamine merits additional research.
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750
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Lau YH, Caswell AH, Garcia M, Letellier L. Ouabain binding and coupled sodium, potassium, and chloride transport in isolated transverse tubules of skeletal muscle. J Gen Physiol 1979; 74:335-49. [PMID: 479825 PMCID: PMC2228522 DOI: 10.1085/jgp.74.3.335] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The affinity and number of binding sites of [3H]ouabain to isolated transverse (T) tubules were determined in the absence and presence of deoxycholate. In both conditions the KD was approximately 53 nM while deoxycholate increased the number of binding sites from 3.5 to 37 pmol/mg protein. We concluded that the ouabain binding sites were located primarily on the inside of the isolated vesicle and that the vesicles were impermeable to ouabain. ATP induced a highly active Na+ accumulation by the T tubules which increased Na+ in the T tubular lumen by almost 200 nmol/mg protein. The accumulation had an initial fast phase lasting 2-3 min and a subsequent slow phase which continued for at least 40 min. The rate of the initial fast phase indicated a turnover number of 20 Na+/s. The Na+ accumulation was prevented by monensin but was unaffected by valinomycin. Ouabain did not influence Na+ uptake, but digitoxin inhibited it. At low K+ the accumulation of Na+ was reduced 3.7-fold below the value at 50 mM K+. 86Rb, employed as a tracer to detect K+, showed a first phase of K+ release while Na+ was accumulated. After 2-3 min, K+ was reaccumulated while Na+ continued to increase in the lumen. T tubules accumulated Cl- on addition of ATP. This suggested that ATP initiated an exchange of Na+ for K+ followed by uptake of Na+ and K+ accompanied by Cl-.
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