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Fardella C, López JM, Valdés ME, Nuñez M, Miranda M. Autoimmune thyroid disease in the puerperium. Predictive value of thyroid enlargement and related hormonal changes occurring during pregnancy. J Endocrinol Invest 1990; 13:283-6. [PMID: 2370422 DOI: 10.1007/bf03349563] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The incidence of goiter detected during pregnancy and its significance as an indicator of autoimmune thyroid disease after delivery was investigated in a sample of 707 pregnant women (81% in their 2nd trimester of gestation). Goiter was detected in 106 subjects (15%). Blood T4, T3, TSH, free T4 index (FT4I), antimicrosomal antibodies (AMA) and urinary iodine excretion were measured in these women and in a control group of gravidas without goiter. These measurements were repeated at 1 and 3 months after delivery. Compared with controls during pregnancy, subjects with goiter had lower FT4I values (11.0 +/- 2.8 vs 9.0 +/- 1.8; p less than 0.01) and higher TSH values (2.9 +/- 0.6 microU/ml vs 4.2 +/- 2.1 microU/ml; p less than 0.01). In contrast, T4, T3, AMA and urinary iodine excretion values were similar in both groups. In subjects with goiter FT4I values increased over pregnancy levels at 1 month (11.2 +/- 2.0; p less than 0.05) and 3 months (14.0 +/- 3.0; p less than 0.05) after delivery; in 29% a biochemical hyperthyroidism (FT4I greater than 13.5) was detected. During the same period TSH values decreased significantly (1 month: 1.9 +/- 0.7 microU/ml; p less than 0.05; 3 months: 2.7 +/- 3.0 microU/ml; p less than 0.05). Frequency of positive AMA increased from 8.6% during pregnancy up to 32.1% in the post-delivery period (p less than 0.01). In the control group no variation in the FT4I, TSH or AMA were observed after delivery. These results indicate that goiter during pregnancy is common in Chilean gravidas and that it has predictive value for the appearance of autoimmune thyroid disease after delivery.
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302
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Di Cola D, Miranda M, Bonfigli A, Zarivi O, Santarone S, Sacchetta P. Changes of a high molecular mass proteinase activity during Bufo bufo development. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1990; 97:751-4. [PMID: 2128227 DOI: 10.1016/0305-0491(90)90118-d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
1. A chymotrypsin-like proteolytic activity was found both in unfertilized eggs and in embryos of Bufo bufo. 2. A dramatical change of activity can be observed in the course of embryonic development. The activity rapidly increases after fertilization up to the stage 9 followed by a fall to a level close to unfertilized eggs. 3. Gel chromatography analysis reveals, in all stages of development, the presence of a single peak of proteinase activity characterized by a very high molecular mass. 4. Proteinase activity, found change during the development of Bufo bufo, was characterized by substrate specificity, protease inhibitor and pH effect. All results obtained suggest that the chymotrypsin-like activity can be assigned to the multicatalytic proteinase.
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303
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Dooley TP, Miranda M, Jones NC, DePamphilis ML. Transactivation of the adenovirus EIIa promoter in the absence of adenovirus E1A protein is restricted to mouse oocytes and preimplantation embryos. Development 1989; 107:945-56. [PMID: 2534379 DOI: 10.1242/dev.107.4.945] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Undifferentiated mouse embryonal carcinoma (EC) cells are capable of transactivating the adenovirus EIIa promoter in the absence of its normal transactivator, E1A protein, suggesting that EC cells contain an E1A-like activity. In an effort to identify where this activity appears during normal mouse development, mouse oocytes and preimplantation embryos were injected with plasmids containing the EIIa promoter coupled to various reporter genes. These expression vectors were fully active in human 293 cells where E1A is present, but were inactive in differentiated fibroblast cell lines unless cotransfected with the E1A gene. In mouse oocytes and preimplantation embryos, EIIa promoter activity in the absence of adenovirus E1A protein was equivalent to or greater than activity of the HSV thymidine kinase promoter coupled to a strong enhancer. Coinjection of the E1A gene failed to stimulate EIIa activity further, perhaps because c-myc protein, which has been reported to transactivate this promoter, was already present at high levels in mouse oocytes. Activation of the EIIa promoter in the absence of E1A was unique to mouse oocytes and preimplantation embryos because gene expression from an EIIa promoter introduced into transgenic mice was observed only in the adult ovary, and particularly in the oocytes. In addition, post-implantation transgenic embryos failed to express the E1A-activatable reporter gene, thereby indicating that expression from the EIIa promoter is restricted to the relatively undifferentiated stages of oogenesis and preimplantation development. These data suggest that cellular promoters of the class that can be transactivated by E1A may serve uniquely to initiate transcription of genes that are needed for preimplantation development.
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Abstract
One hundred and eighty-seven children with identified bacterial meningitis were treated with intravenous cefotaxime: 15 patients were neonates, 79 infants, and 93 were aged from 1 to 14 years. Causative organisms were: Neisseria meningitidis in 80 cases, Streptococcus pneumoniae in 41, Haemophilus influenzae in 40, enteric gram-negative bacilli in 20 and Staphylococcus spp. in six. Enteric gram-negative bacilli included: Salmonella spp. in 14 cases, Klebsiella pneumoniae in two, and Escherichia coli, Enterobacter sakazakii and Acinobacter calcoaceticus in one each; in one case the organism was not specified. Daily dose of cefotaxime was 150 to 300 mg/kg. Concomitant treatment with an aminoglycoside was used in seven cases. One hundred and seventy-two patients (92.0%) were cured. Fever persisted for a mean of five days and meningeal signs for a mean of four days. Fifteen (8.0%) patients died: most [13] of them were admitted in coma, and two in shock. Death occurred in the first 48 h in ten cases. Sterilization of CSF was achieved in the first 72 h of treatment in 155 (90.1%) of the cured patients. Cefotaxime was well tolerated. CSF penetration of cefotaxime was evaluated in seven patients: concentrations ranged from 0.499 mg/l to 2.829 mg/l. Based on this clinical study, cefotaxime is an effective and safe drug for the treatment of childhood bacterial meningitis.
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Miranda M, Amicarelli F, Ragnelli A, Poma A, Arcadi A. Effect of cholesterol on the DOPA oxidase of liposome-integrated mushroom tyrosinase. ACTA ACUST UNITED AC 1989. [DOI: 10.1016/0166-6622(89)80308-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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306
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Abstract
Epidemiological and clinical aspects of 50 consecutive patients, 47 adults and three children, hospitalized between 1977 and 1987 for human leptospirosis, were reviewed. 45 (90%) of the patients were from rural regions. 32 (64%) cases occurred in individuals at occupational risk for the infection. 35 (70%) cases were registered in the warm season. The source of infection was known in 34 (68%) cases. Weil's disease was diagnosed in 31 (62%) patients, aseptic meningitis in 12 (24%) and acute unexplained fever in seven (14%). Haemodialysis was required for 11 (35%) patients with Weil's disease. Three (6%) patients died. Cause of death was massive gastrointestinal haemorrhage in two and renal failure in one. Leptospira icterohaemorrhagiae was responsible for 39 (78%) cases, Leptospira canicola for six (12%), Leptospira grippotyphosa for two (4%), and Leptospira australis, Leptospira ballum and Leptospira sejroe, for one case each. A muscle biopsy was performed in six patients and a renal biopsy in three. Focal necrotic muscular changes, with mild mononuclear infiltrate, were found. Pigmented casts in distal convoluted tubules, mild interstitial inflammatory infiltrate and mesangial enlargement of some glomeruli were observed in kidney biopsies. A good knowledge of the protean clinical manifestations of leptospirosis and an accurate laboratory study are required for a correct diagnosis.
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307
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Miranda M, Amicarelli F, Poma A, Ragnelli AM, Bonfigli A, Zarivi O, Aimola P, Botti D. Morphofunctional aspects of lipo-melanosome as a model for the organelle phenotype of normal and tumor pigment cells. Ann N Y Acad Sci 1988; 551:448-51. [PMID: 3149882 DOI: 10.1111/j.1749-6632.1988.tb22378.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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308
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Amicarelli F, Bonfigli A, Zarivi O, Poma A, Miranda M. Efflux of cytotoxic species within lipo-melanosome membrane. Ann N Y Acad Sci 1988; 551:141-3. [PMID: 2854417 DOI: 10.1111/j.1749-6632.1988.tb22331.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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309
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Miranda M, Martínez F. [Fascioliasis hepatica causing bile duct obstruction]. Rev Med Chil 1988; 116:1186-90. [PMID: 3267903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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310
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Miranda M, Amicarelli F, Poma A, Ragnelli AM, Arcadi A. Liposome-entrapped tyrosinase: a tool to investigate the regulation of the Raper-Mason pathway. BIOCHIMICA ET BIOPHYSICA ACTA 1988; 966:276-86. [PMID: 3137975 DOI: 10.1016/0304-4165(88)90077-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The effect of the entrapment of mushroom tyrosinase (EC 1.14.18.1) within liposomes on the enzyme activity and Km vs. L-3,4-dihydroxyphenylalanine is reported in the present work; the effect of cholesterol insertion within liposome membranes on the enzyme activity has also been studied. The oxidation rates of various monophenols and diphenols by free and liposome-integrated mushroom tyrosinase were measured and the oxidation latencies vs. different substrates investigated. The different substrates are apparently oxidized according to the properties of the substituents as electron donors or acceptors; the Km values vs. L-3,4-dihydroxyphenylalanine calculated on measuring O2 consumption are higher than those calculated on measuring the dopachrome production rates. It is interesting that natural substrates of tyrosinase are oxidized according to a negative catalysis by the liposome-entrapped enzyme; this point is discussed in relation to the well known cytotoxicity of some intermediates of the Raper-Mason pathway.
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DePamphilis ML, Herman SA, Martínez-Salas E, Chalifour LE, Wirak DO, Cupo DY, Miranda M. Microinjecting DNA into mouse ova to study DNA replication and gene expression and to produce transgenic animals. Biotechniques 1988; 6:662-80. [PMID: 3078722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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312
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Miranda M, Pimenta J. [Atrial flutter with exit block of 2d degree Grau: an indication of ectopic automatism]. Arq Bras Cardiol 1988; 50:431-2. [PMID: 3248065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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313
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Lobò A, Pérez-Echeverria J, Artal J, Rubio L, Escolar MV, González-Torrecillas JL, Morera B, Dia JL, Miranda M. Psychiatric morbidity among medical out-patients in Spain: a case for new methods of classification. J Psychosom Res 1988; 32:355-64. [PMID: 3236264 DOI: 10.1016/0022-3999(88)90018-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A study was carried out to document the psychiatric disturbances among consecutive first-day attenders to an internal medicine out-patient clinic in Spain. Subjects were interviewed in three different stages using standardized procedures, basically the Clinical Interview Schedule (CIS). As hypothesized, the rate of disturbances was high (46.9%) and their classification with ICD-9 criteria was problematic. Minor affective disturbances were the most common diagnoses; the distribution of anxiety and depression scores followed the 'two correlated dimensions' model. The psychopathological differences between 'cases' and 'non-cases' seemed quantitative rather than qualitative. Absence of organicity, a pattern of multiple consultations and social problems were more frequent among the 'cases'. These data support the use of multiaxial classificatory systems. Ten supervised interviews significantly improved the internist recognition of 'cases' and the suggestion is made that a single routine question about the patients' mood would sensibly improve the detection rates.
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Miranda M, di Ilio C, Bonfigli A, Arcadi A, Pitari G, Dupre S, Federici G, del Boccio G. A study on the in vitro interaction between tyrosinase and glutathione S-transferase. BIOCHIMICA ET BIOPHYSICA ACTA 1987; 913:386-94. [PMID: 3109490 DOI: 10.1016/0167-4838(87)90150-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The actions of glutathione S-transferase and tyrosinase on the in vitro production of glutathionyl-3,4-dihydroxyphenylalanine and the dopachrome level in the presence of GSH and L-3,4-dihydroxyphenylalanine were studied. No clear evidence of complementarity between tyrosinase and glutathione S-transferase was observed; on the contrary, in the presence of glutathione S-transferase the glutathionyl-3,4-dihydroxyphenylalanine yield was lower than with tyrosinase only, as measured by HPLC. It is concluded that the spontaneous conjugation of GSH with dopaquinone should probably be high enough to scavenge the toxic quinone and to produce precursors for phaeomelanogenesis.
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315
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Miranda M, Bonfigli A, Zarivi O, Manilla A, Cimini AM, Arcadi A. Restriction patterns of model DNA treated with 5,6-dihydroxyindole, a potent cytotoxic intermediate of melanin synthesis: effect of u.v. irradiation. Mutagenesis 1987; 2:45-50. [PMID: 2842578 DOI: 10.1093/mutage/2.1.45] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The interaction of 5,6-dihydroxyindole, a putative cytotoxic intermediate of melanin synthesis, with model lambda phage DNA has been investigated by using type II restriction endonucleases and CsCl buoyant density centrifugation. As evidenced by agarose gel electrophoresis and density gradient profiles, the 5,6-dihydroxyindole or u.v. treated DNAs, restricted or not, are modified. U.v. irradiation enhances 5,6-dihydroxyindole binding to DNA, but no sequence specific binding was observed. The action of L-3,4-dihydroxyphenylalanine on the restriction patterns of lambda phage DNA was also investigated and the effect appeared smaller, by qualitative evaluation, than that produced by 5,6-dihydroxyindole.
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Del Boccio G, Di Ilio C, Miranda M, Manilla A, Zarivi O, Bonfigli A, Federici G. Glutathione transferase activity during Bufo bufo development. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1987; 86:749-53. [PMID: 3107890 DOI: 10.1016/0305-0491(87)90222-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
High levels of glutathione transferase activity were measured during the development of the embryos of Bufo bufo including unfertilized eggs. After stage 4 glutathione transferase activity gradually decreased until stage 25 when the minimum was reached. No change in the number of isozymes was noted during development according to isoelectric focusing analysis performed on the cytosolic fractions of selected stages.
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317
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Miranda M, Clements DL. Useful subjective visual performance with the Permalens X-L contact lens in patients with corneal astigmatism. BOLETIN DE LA ASOCIACION MEDICA DE PUERTO RICO 1986; 78:386-90. [PMID: 3463322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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318
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Di Ilio C, Del Boccio G, Miranda M, Manilla A, Zarivi O, Federici G. Glutathione peroxidases and glutathione reductase activities during Bufo bufo development. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. C, COMPARATIVE PHARMACOLOGY AND TOXICOLOGY 1986; 83:9-12. [PMID: 2869913 DOI: 10.1016/0742-8413(86)90004-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Glutathione peroxidases and glutathione reductase activities are expressed from the early stage of Bufo bufo development. Selenium-dependent and selenium-independent glutathione peroxidase activities fluctuated independently. The activity of selenium-independent was found to be higher than that of selenium-dependent glutathione peroxidase through all stages of development. Glutathione reductase activity, after a slight fall from stage 4 to stage 7, constantly increased up to stage 25.
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319
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Lolas M, Rufín F, Miranda M. [Comparative study of 2 technics of sclerotherapy for esophageal varices in patients with portal hypertension]. Rev Med Chil 1985; 113:961-5. [PMID: 3879772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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320
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Miranda M, García-Castiñeiras S. Retinal stimuli in ocular accommodation. BOLETIN DE LA ASOCIACION MEDICA DE PUERTO RICO 1985; 77:368-70. [PMID: 3865662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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321
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Miranda M, Botti D, Bonfigli A, Arcadi A. 5,6-Dihydroxyindole oxidation by mammalian, mushroom and amphibian tyrosinase preparations. BIOCHIMICA ET BIOPHYSICA ACTA 1985; 841:159-65. [PMID: 3926006 DOI: 10.1016/0304-4165(85)90017-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The oxidation of 5,6-dihydroxyindole by tyrosinases from mushroom, Harding-Passey melanoma, bovine eye and Bufo bufo embryo has been investigated. The apparent Km values for this substrate were measured and found to be of the same order of magnitude as those for L-tyrosine and L-3,4-dihydroxyphenylalanine, as reported in the literature (5 x 10(-4) M). The 5,6-dihydroxyindole oxidases of mushroom and T4 melanoma isozyme are sensitive to phenylthiourea, while, on the other hand, those from crude preparations of bovine and B. bufo tyrosinases are not sensitive to the inhibitor in an evident manner. The action of some indole derivatives on the 5,6-dihydroxyindole oxidase of mushroom has also been investigated.
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322
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Phaff HJ, Starmer WT, Tredick J, Miranda M. Pichia deserticola and Candida deserticola, Two New Species of Yeasts Associated with Necrotic Stems of Cacti. ACTA ACUST UNITED AC 1985. [DOI: 10.1099/00207713-35-2-211] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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323
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Miranda M, Defilippi C, Valenzuela JE. Abnormalities of interdigestive motility complex and increased duodenogastric reflux in gastric ulcer patients. Dig Dis Sci 1985; 30:16-21. [PMID: 3965271 DOI: 10.1007/bf01318365] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Just as cyclic changes in motility and secretions occur during fasting, recent evidence demonstrates that duodenogastric reflux during fasting is also cyclic and related to the motility and secretory variations. We investigated the characteristics of the migrating motility complex and duodenogastric reflux in 17 patients with gastric ulcer and compared these characteristics to those of 16 healthy subjects. We found three abnormalities of the complex in patients with gastric ulcer: (1) the antral motility was significantly decreased during the phase II of the complex (P less than 0.05) when compared to controls; (2) in about two thirds of them, the phase III of the complex was initiated at the duodenum or more distally; and (3) the mean bile salt concentration in the gastric aspirate was significantly higher (P less than 0.05) than that of the controls. We observed no relationship between the ulcer activity, the location of the crater, and the motility or reflux abnormalities.
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324
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Barker JS, East PD, Phaff HJ, Miranda M. The ecology of the yeast flora in necroticOpuntia cacti and of associatedDrosophila in Australia. MICROBIAL ECOLOGY 1984; 10:379-399. [PMID: 24221180 DOI: 10.1007/bf02015562] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A survey was made of the yeast communities isolated from necrotic tissue of 4 species of prickly-pear cacti (Opuntia stricta, O. tomentosa, O. monacantha, andO. streptacantha) which have colonized in Australia. Yeast communities were sampled from a number of localities and at different times. Cactus specific yeasts accounted for 80% of the total isolates, and the 3 most common species contributed 63% of the total. Comparisons of the species compositions of the yeast communities indicated that the differences among communities were greater betweenOpuntia species than between different localities within a single cactus species, and also that differences between years were greater than average differences between localities within years. Multivariate statistical tests of association between yeast community and physical features of rots indicated that temperature, pH, and age of rot all exerted some influence on the structure of the yeast community. Similar analyses involvingDrosophila species inhabiting these cactus rots suggested the existence of complex associations betweenDrosophila community, yeast community, and physical and chemical attributes of the cactus necroses.
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325
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Dooley CP, Miranda M, Valenzuela JE. Comparative effect of gastrin on hydrogen ion secretion, antroduodenal motility and the interdigestive motility complex (IDMC) in man. Dig Dis Sci 1984; 29:714-20. [PMID: 6745032 DOI: 10.1007/bf01312943] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The physiological role of gastrin in H+ secretion is well established. We decided to study the effects of physiological doses of gastrin (as evidenced by H+ secretion and postprandial serum gastrin levels) on antroduodenal motility in order to delineate its role in antral motility regulation. Nine healthy male subjects, mean age 31 years, had two studies on different days. On day 1, gastroduodenal motility was monitored with a continuously perfused catheter system while gastric secretions were aspirated. After a basal period of 45 min, human synthetic gastrin (hG-17) was infused intravenously in consecutive doses of 6.25, 25, 100, and 400 pmol/kg/hr during 45 min each. On day 2, all subjects had a standard protein meal. Blood was withdrawn on both days for gastrin measurement by RIA. Increasing amounts of hG-17 caused a stepwise increase in serum gastrin and acid output. The D50 for H+ secretion was 25 pmol/kg/hr hG-17. The mean postprandial gastrin level was 31 +/- 5 pM, a level which was comparable to that seen during infusion of hG-17 6.25 pmol/kg/hr. At these serum gastrin levels, antral motility was either reduced or unchanged. Duodenal motility was unchanged. A reduction in the antroduodenal motility ratio was seen at these levels, but there was no interruption of the interdigestive motility complex. These results suggest that at physiological levels, gastrin by itself does not seem to have a major role in human antroduodenal motility regulation.
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326
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González B, Elgueta S, Talesnik E, Montaña N, Rodríguez MS, Valenzuela M, Miranda M, Varas M. [Lupus erythematosus disseminatus in childhood. Clinical study and survival in 31 cases]. REVISTA CHILENA DE PEDIATRIA 1984; 55:238-44. [PMID: 6084265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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327
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Wijayasinghe MS, Miranda M, Smith NE, Baldwin RL, Wijayasinghe C, Har SA. A yeast related ethanol intoxication syndrome in experimental calves: prevention with nystatin. THE CANADIAN VETERINARY JOURNAL = LA REVUE VETERINAIRE CANADIENNE 1984; 25:251-3. [PMID: 17422416 PMCID: PMC1790578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
In a calf nutrition-metabolism study in which a high glucose (60% glucose and 3% lard) versus a high fat (23% glucose and 30% lard) milk replacer were compared, a syndrome characterized by anorexia, an unstable gait, depression, a distended abdomen and an odor of alcohol on the breath was observed in some calves. These signs were associated with intoxicating levels of plasma ethanol and the predominance of the yeast species Torulopsis glabrata in gastrointestinal contents of afflicted calves. Nystatin, a yeast inhibitor, was extremely useful in preventing the problem.
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328
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Coupe B, Thierry P, Colin P, Miranda M, Gault C. [Myasthenia and Basedow's hyperthyroidism]. ARCHIVES FRANCAISES DE PEDIATRIE 1984; 41:341-3. [PMID: 6547817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
Abstract
The authors report an exceptional case of myasthenia gravis associated with Graves' disease. Myasthenia gravis appeared at age 8 years. Hyperthyroidism was diagnosed at age 12 1/2 and quickly worsened, with signs of cardiothyrotoxicosis. In addition to the diagnostic difficulties, the immunologic origin seems to be implicated in these diseases. Thymectomy associated with subtotal thyroidectomy was performed, with good results during an 18 months follow-up.
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329
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Miranda M, Botti D, Di Cola M. Possible genotoxicity of melanin synthesis intermediates: tyrosinase reaction products interact with DNA in vitro. MOLECULAR & GENERAL GENETICS : MGG 1984; 193:395-9. [PMID: 6423931 DOI: 10.1007/bf00382074] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The actual cellular target of the cytotoxic intermediates of melanin synthesis is not yet known. In the present paper it is shown that eukaryotic DNA binds in vitro to soluble reaction products of tyrosinase (EC 1.14.18.1) and is physically modified, as ascertained by the following criteria: (a) buoyant density in cesium chloride density gradients; (b) polyacrylamide gel electrophoresis; (c) deoxyribonuclease (EC 3.1.4.5) test; (d) electron microscopy. The results reported here support the view that DNA itself may be a target for the cytotoxic intermediates of melanin synthesis.
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330
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Miranda M, Botti D, Bonfigli A, Ventura T, Arcadi A. Tyrosinase-like activity in normal human substantia nigra. GENERAL PHARMACOLOGY 1984; 15:541-4. [PMID: 6441736 DOI: 10.1016/0306-3623(84)90212-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
A tyrosinase-like activity was found in human substantia nigra by polyacrylamide gel electrophoresis of fractions prepared from homogenates of the substantia nigra. The enzyme activity was detected by staining the gels with L-3,4-dihydroxyphenylalanine, dopamine and 5,6-dihydroxyindole as substrates for tyrosinase (EC 1.14.18.1). A case of parkinsonism does not show the L-3,4-dihydroxyphenylalanine and dopamine oxidase activities.
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331
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Rufín F, Llorens P, Altschiller H, Miranda M. [Comparative study of 2 treatment schedules with cimetidine in patients with duodenal ulcer]. Rev Med Chil 1983; 111:1018-23. [PMID: 6676809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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332
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Abstract
Under electrophysiologic studies, 44 asymptomatic chagasic individuals were studied. The mean age was 39.9 years, with 26 being male. The surface ECG showed normal tracings in 12 patients, left anterior fascicular block in three, incomplete right bundle branch block in two, and right bundle branch block in 27 (isolated in six, associated with left anterior fascicular block in 19 and with left posterior fascicular block in two). Sinus nodal dysfunction was found in eight (18.1%), and 29 (66%) presented with some form of abnormal AV nodal behavior during atrial stimulation. Repetitive ventricular beats were recorded in 17 (41.4%) patients. Finally, in 19 (43.1%), patterns of dysfunction at two or more levels of the cardiac conducting system were found. It is concluded that the chagasic cardiomyopathy produces diffuse lesions in the conducting tissue of the human heart in the stages when the disease is detected, and that the individuals are still asymptomatic.
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333
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Csendes A, Elizalde L, González P, Miranda M, Medina E, Gallo G, Morales A, Godoy M. [Variables which affect the clinical course of patients with upper digestive hemorrhage. A prospective analysis]. Rev Med Chil 1983; 111:676-83. [PMID: 6334878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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334
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Miranda M, Botti D. Harding-passey mouse-melanoma tyrosinase inactivation by reaction products and activation by L-epinephrine. GENERAL PHARMACOLOGY 1983; 14:231-7. [PMID: 6404691 DOI: 10.1016/0306-3623(83)90002-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
1. Harding-Passey mouse-melanoma tyrosinase (EC 1.14.18.1) is inhibited during L-3,4-dihydroxyphenylalanine oxidation by reaction products. L-3,4-dihydroxyphenyl 3-[14C]alanine oxidation products bind to the enzyme, as demonstrated by gel electrophoresis and radioactivity measurements. 2. The enzyme interacts with indoles and oxidizes dopamine and norepinephrine. 3. L-epinephrine activates tyrosinase at non hormonal concentrations and bovine serum albumin protects the enzyme from auto-inhibition. 4. The inhibition of the Harding-Passey mouse-melanoma tyrosinase, during substrate oxidation, is very similar to that of mushroom enzyme.
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335
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Barker JSF, Toll GL, East PD, Miranda M, Phaff HJ. Heterogeneity of the yeast flora in the breeding sites of cactophilic Drosophila. Can J Microbiol 1983. [DOI: 10.1139/m83-002] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Yeasts were isolated from 278 rots in cladodes and basal stems of Opuntia stricta sampled over 15 months at one locality. The most common yeast species among 370 nonidentical isolates representing 20 species were Candida sonorensis (27% of isolates) and Pichia cactophila (24%). These species generally were present in all months and throughout the area sampled. Other relatively common species (3–9% of alt isolates) had much more restricted distributions in both time and space. The mean number of yeast species per rot was 1.27 ± 0.082, and no yeasts were isolated from 20% of the rots sampled. Significant differences among months or seasons in average number of yeast species per rot were due primarily to lower numbers in the summer and winter months, while differences among rot types resulted mainly from a higher number in the longer persisting basal stem rots. Both hierarchical diversity analysis and analysis of the distributions of the 10 most common yeast species showed temporal effects (month or season) to be the major component contributing to heterogeneity, while microgeographic effects and rot type also were significant. The seasonal and microgeographic heterogeneity are interpreted in terms of longer persisting rots in part of the locality providing a reservoir for yeast species through the winter and are discussed in relation to the maintenance of genetic variation in cactophilic Drosophila that utilize the rots as feeding and breeding sites.
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336
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Miranda M, Botti D, Ragnelli AM, di Cola M. A study on melanogenesis and catecholamine biosynthesis during Bufo bufo development. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1982; 224:217-22. [PMID: 6818321 DOI: 10.1002/jez.1402240212] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Tyrosinase and L-DOPA decarboxylase activities have been investigated during Bufo bufo development since catecholamines and melanin are formed from common substrates in homologous cells. Catecholamines first appear at stage 13 (neural plate), but tyrosinase, at a very low level, and L-DOPA decarboxylase are present throughout all of prior development. Hence, L-DOPA decarboxylase activity is not likely to be correlated with the control of catecholamine synthesis, although at stage 17 it is mainly localized in the nonneural part of the embryo. The distribution of young melanosomes and L-DOPA decarboxylase suggest a separation between melanogenesis and catecholamine synthesis.
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337
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Miranda M, Botti D, Pantani C, Ragnelli AM, di Cola M. Developmental aspects of hexose metabolism in Bufo bufo. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1982; 224:211-5. [PMID: 6296268 DOI: 10.1002/jez.1402240211] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Due to the close correlation between glucose mobilization and utilization within animal tissues, in this paper, the stages of appearance of phosphorylase, glucose-6-phosphatase and hexokinase as well as the levels of some intermediates of glucose metabolism have been investigated during Bufo bufo development. Phosphorylase first appears at stage 13 and is dominant in the neural part of the embryo, but, after this stage, increases relatively more in the nonneural one. Hexokinase appears at stage 17 and glucose-6-phosphatase soon after. Phosphorylase appearance at stage 13 is correlated with an increase of lactate content in the embryo; this may indicate a metabolization of hexoses. On this basis, the subsequent appearance of hexokinase and glucose-6-phosphatase activities also seems coherent with hexose mobilization and utilization within embryo. No direct causative factor for the changes observed was evident.
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Alcover A, Izquierdo M, Stollar D, Kitagawa Y, Miranda M, Alonso C. In situ immunofluorescent visualization of chromosomal transcripts in polytene chromosomes. Chromosoma 1982; 87:263-77. [PMID: 6186443 DOI: 10.1007/bf00327629] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The induction and distribution of chromosomal transcripts in the polytene chromosomes of D. melanogaster and D. hydei has been investigated by indirect immunofluorescence using an antiserum directed against DNA/RNA hybrids. The fluorescence was intense and occurred in most of the chromosomal subdivisions when the chromosomes were exposed to denaturing conditions and then allowed to reanneal. The extent of hybrid formation depended both on the extent of DNA denaturation and on the maintenance of RNA integrity. Fluorescence was absent from chromosomes treated with pancreatic RNase before denaturation. The velocity of the chromosomal DNA/RNA hybridization reaction and the effects of the initiation inhibitor of RNA synthesis, DRB, suggest that in order to hybridize the RNA has to be located in its transcriptional compartment. Even though overall patterns of fluorescence seem to be similar during a developmental stage, variations were observed, particularly some correlated with puff induction after ecdysone stimulation.
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Csendes A, Miranda M, Rappoport J, Carrasco-Ruiz O, Escauriaza A, Braghetto I, Oyarce R, Parr G, Kuschel C, Velasco N, Amat J, Delgado M. [Clinical characteristics, morbidity and mortality of 3 surgical technics in duodenal ulcer. Cooperative interhospital study of 906 patients]. Rev Med Chil 1982; 110:242-8. [PMID: 7156573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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340
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Alcover A, Izquierdo M, Stolar D, Miranda M, Alonso C. Analytical studies of chromosomal transcription detected by an endogenous hybridization technique (EHT) using autoradiography and indirect immunofluorescence in Drosophila hydei. ACTA EMBRYOLOGIAE ET MORPHOLOGIAE EXPERIMENTALIS ("HALOCYNTHIA" ASSOCIATION") 1981; 2:131-40. [PMID: 7041502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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341
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Miranda M, Botti D, Di Cola M, Ragnelli AM. Some properties of Bufo bufo tyrosinase during development. EXPERIENTIA 1981; 37:938-9. [PMID: 6795053 DOI: 10.1007/bf01971764] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Tyrosinase expression during Bufo bufo development has been investigated. Until stage 19, only 1 electrophoretic band is detectable, but at a later stage (25) 3 bands appear. The Km for L-3,4-dihydroxyphenylalanine (L-dopa) was also determined.
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342
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Casado de Frías E, Valverde Moreno F, López-Ibor B, Elosegui J, Miranda M, Vázquez L. [Treatment of juvenile rheumatoid arthritis (author's transl)]. ANALES ESPANOLES DE PEDIATRIA 1981; 15:48-62. [PMID: 7316291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
A revision of the treatment of the juvenile chronic arthritis (JCA) is made, Salicylates, still in use, require control of the salicylate level in order to obtain a higher efficiency and to prevent toxicity. New drugs appeared in the last years (by-products of propionic acid, tolmetin acid, fenclofenic...), are useful as an alternative for salicylates and with very little toxicity. Steroid therapy has to be reserved for serious systemic illness only, and slow acting drugs as antimalarials, gold and pencillamine, were only used in those cases with severe persistant activity and in cases of corticosteroid dependents. Use of the immunosuppressive therapy, is justified only in exceptional cases. Immunostimulants (transfer factor, Levamisol) are still in experimental phase. Presentation of the last five years' experience of the Pediatric Department is given. It concerns 25 cases of JCA, 5 systemic forms, 9 polyarticular and 11 forms of pauci-articular. Therapy is based on the predominant use of aspirin and on steroid therapy for the system forms. The efficiency of the treatment is not easy to evaluate regarding consideration of the unpredictable evaluation of the illness.
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Abstract
Pressure measurements of the whole extrahepatic biliary tract were performed in dogs using constant perfusion techniques. Studies were done during general anesthesia and in conscious trained dogs. Gallbladder intraluminal fasting pressure was significantly lower than common bile duct pressure. No motor activity was demonstrated in the common bile duct. At the cysticocholedochal junction a static high-pressure zone was observed, probably due to mechanical factors. At the level of the choledochoduodenal junction, a high-pressure zone with a sphincter behavior was demonstrated, with a resting pressure of 38 cm H2O above intraduodenal pressure and with rhythmic contractions with a mean amplitude of 88 cm H2O above duodenal pressure. Duodenal motility was completely different from sphincter dynamics. No differences in pressure values were seen during general anesthesia or in conscious state.
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Csendes A, Miranda M, Espinoza M, Velasco N, Henríquez A. Perimeter and location of the muscular gastroesophageal junction or 'cardia' in control subjects and in patients with reflux esophagitis or achalasia. Scand J Gastroenterol 1981; 16:951-6. [PMID: 7323721 DOI: 10.3109/00365528109181829] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The location and perimeter of the true muscular gastroesophageal junction or cardia were determined during operation in 6 patients with achalasia, in 20 control subjects, and in 40 patients with reflux esophagitis. These two latter groups were submitted to highly selective vagotomy, owing to duodenal ulcer in the control subjects and as part of the surgical technique in reflux esophagitis patients. The careful dissection and isolation of the distal 5-6 cm of the esophagus and esophagogastric junction permitted us to measure the location and perimeter very precisely. There was a very close correlation between the distance incisors-beginning of gastroesophageal sphincter measured preoperatively and the distance incisors-cardia measured during surgery. The cardia could be clearly identified by external inspection corresponding to the limit between the longitudinal muscle layer of the esophagus and the serosal surface of the stomach. The perimeter of the cardia in the patients with reflux esophagitis was significantly larger than the perimeter of the control subjects (p less than 0.001). Intraoperative manometry demonstrated that the external limit of the cardia corresponded to the beginning of the gastroesophageal sphincter. Patients with achalasia had significantly smaller perimeter than controls or reflux esophagitis patients (p less than 0.001).
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345
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Pimenta J, Miranda M, Silva LA. Abnormal atrioventricular nodal response patterns in patients with long-term Chagas' disease. Chest 1980; 78:310-5. [PMID: 6772388 DOI: 10.1378/chest.78.2.310] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Thirty-two volunteers with positive serologic tests for Chagas' disease were submitted to electrophysiologic studies. No one had documented tachyarrhythmias, heart failure, PR interval shorter than 0.12 or longer than 0.20 msec, pre-excitation or cardiac enlargement. The atrioventricular (AV) nodal function study under programmed atrial stimulation revealed abnormal AV nodal function in nine (28.1 percent) with long-term Chagas' disease. Due to the high incidence of the longitudinal dissociation in this disease, and based on previously reported histopathologic findings that demonstrate the involvement of the right side of the AV node and His bundle, this study suggests that the abnormal AV nodal responses may be secondary to the organic alterations produced by Chagas' disease.
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Pimenta J, Censoni LG, Miranda M. [Effect of atenolol on ST segment elevation during acute phase of transmural myocardial infarction of the anterior wall]. Arq Bras Cardiol 1980; 34:295-8. [PMID: 7436788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
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347
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Miranda M, Pimenta J, Silva LA. [Beats with narrow "QRS" induced by endocavitary stimulation in chronic Chagas patients with a complete right bundle-branch block of long standing]. Arq Bras Cardiol 1980; 34:29-33. [PMID: 6773506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
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348
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Holzschu DL, Presley HL, Miranda M, Phaff HJ. Identification of Candida lusitaniae as an opportunistic yeast in humans. J Clin Microbiol 1979; 10:202-5. [PMID: 292646 PMCID: PMC273129 DOI: 10.1128/jcm.10.2.202-205.1979] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Four yeast strains, causally associated with infection in a patient with acute myelogenous leukemia, were identified by standard methods currently used in yeast taxonomy as representatives of Candida lusitania van Uden et do Carmo-Sousa. Because this species has not been recognized previously as an opportunistic yeast in humans, molecular taxonomic methods were applied to confirm its identity. The nuclear deoxyribonucleic acid (DNA) base composition of two clinical isolates was shown to be 45.1 mol% guanine plus cytosine as compared to 44.7 mol% guanine plus cytosine for the type strain of this species. DNA/DNA reassociation experiments revealed more than 95% complementarity between the DNAs from the clinical isolates and that of the type strain of C. lusitaniae, thus confirming their classification by conventional taxonomy. A key is provided to differentiate C. lusitaniae from two phenotypically similar Candida species.
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Miranda M, Csendes A, Guarda R, Aguilera S, Henríquez A, Ayala M. [Manometric and radiologic alterations of the esophagus in patients with systemic sclerosis (author's transl)]. Rev Med Chil 1979; 107:730-2. [PMID: 545566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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350
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Miranda M, Urbani G, Di Vito L, Botti D. Inhibition of tyrosinase by indole compounds and reaction products. Protection by albumin. Biochim Biophys Acta Gen Subj 1979; 585:398-404. [PMID: 114228 DOI: 10.1016/0304-4165(79)90084-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Tyrosinase activity decreases as the reaction proceeds and is inhibited by L-3,4-dihydroxyphenylalanine oxidation products. Indole and tryptophan inhibit tyrosinase reaction and bovine albumin protects against end-product(s) inhibition or inactivation. Since the same tyrosinase reaction products are indole compounds and some authors reported the binding of indole derivatives with albumin, it is here suggested that indole intermediates of melanin synthesis inhibit or inactivate tyrosinase.
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