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López-Llano J, Campos LA, Bueno M, Sancho J. Equilibrium Φ-Analysis of a Molten Globule: The 1-149 Apoflavodoxin Fragment. J Mol Biol 2006; 356:354-66. [PMID: 16364364 DOI: 10.1016/j.jmb.2005.10.086] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2005] [Revised: 10/27/2005] [Accepted: 10/28/2005] [Indexed: 11/19/2022]
Abstract
The apoflavodoxin fragment comprising residues 1-149 that can be obtained by chemical cleavage of the C-terminal alpha-helix of the full-length protein is known to populate a molten globule conformation that displays a cooperative behaviour and experiences two-state urea and thermal denaturation. Here, we have used a recombinant form of this fragment to investigate molten globule energetics and to derive structural information by equilibrium Phi-analysis. We have characterized 15 mutant fragments designed to probe the persistence of native interactions in the molten globule and compared their conformational stability to that of the equivalent full-length apoflavodoxin mutants. According to our data, most of the mutations analysed modify the stability of the molten globule fragment following the trend observed when the same mutations are implemented in the full-length protein. However, the changes in stability observed in the molten globule are much smaller and the Phi-values calculated are (with a single exception) below 0.4. This is consistent with an overall and significant debilitation of the native structure. Nevertheless, the fact that the molten globule fragment can be stabilised using as a guide the native structure of the full-length protein (by increasing helix propensity, optimising charge interactions and filling small cavities) suggests that the overall structure of the molten globule is still quite close to native, in spite of the lowered stability observed.
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Vaisman M, Bittencourt M, Rey H, Rangel F, Rocha R, Costa Filho R, Campos L, Gutierrez F, Bronchtein A, Esporcatte R. Crit Care 2005; 9:P28. [DOI: 10.1186/cc3572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Baltatu O, Campos LA, Bader M. Genetic targeting of the brain renin-angiotensin system in transgenic rats: Impact on stress-induced renin release. ACTA ACUST UNITED AC 2004; 181:579-84. [PMID: 15283773 DOI: 10.1111/j.1365-201x.2004.01333.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The advance of genetic technologies to permit tissue-specific targeted gene manipulation allowed the development of transgenic models with alterations of the renin-angiotensin (RAS) solely in the brain. We have used such methodology to develop a transgenic rat with a brain specific alteration of the RAS [TGR(ASrAOGEN)], in order to elucidate a causative role for the brain RAS and its relevance in different pathophysiological processes. The TGR(ASrAOGEN) rats have decreased levels of angiotensinogen (AOGEN) throughout the brain because of an antisense inhibition of the astroglial AOGEN synthesis. In this review we aimed at summarizing the experience obtained from utilizing the TGR(ASrAOGEN) rat model to study the brain RAS and present novel results providing evidence for the involvement of this system in stress-induced renin release.
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Campos LA, Couto AS, Iliescu R, Santos JA, Santos RAS, Ganten D, Campagnole-Santos MJ, Bader M, Baltatu O. Differential regulation of central vasopressin receptors in transgenic rats with low brain angiotensinogen. ACTA ACUST UNITED AC 2004; 119:177-82. [PMID: 15120478 DOI: 10.1016/j.regpep.2004.02.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2003] [Revised: 01/28/2004] [Accepted: 02/04/2004] [Indexed: 10/26/2022]
Abstract
The consequences of permanent alteration to the brain renin-angiotensin system (RAS) on central vasopressinergic system was studied in transgenic rats with low brain angiotensinogen [TGR(ASrAOGEN)]. Levels of vasopressin (AVP) and V1a receptor mRNAs were measured by ribonuclease protection assay (RPA) and AVP by radioimmunoassay (RIA). AVP (100 pmol/50 nl) was microinjected into the nucleus tractus solitarii (NTS) of urethane-anesthetized TGR(ASrAOGEN) and Sprague-Dawley (SD) rats and the mean arterial pressure (MAP) and heart rate (HR) baroreflex induced by phenylephrine were evaluated. AVP but not its mRNA levels were significantly lower in the hypothalamus and hypophysis of TGR(ASrAOGEN) rats. Brainstem V1a mRNA levels were significantly higher in TGR(ASrAOGEN) in comparison to SD rats (5.2+/-0.4% vs. 3.3+/-0.2% of beta-actin mRNA, P<0.05). In contrast, the hypothalamic V1a mRNA levels in TGR(ASrAOGEN) were not different from those found in SD rats. AVP microinjections induced a greater decrease in MAP in TGR(ASrAOGEN) in comparison with SD rats (-19.9+/-5.2 vs. -7.5+/-0.7 mm Hg, P<0.01). The significantly higher baroreflex sensitivity observed in TGR compared to that of SD rats was normalized after AVP microinjection. The increased brainstem V1a mRNA levels and sensitivity to AVP in TGR(ASrAOGEN) rats indicates a functional upregulation of AVP receptors in the NTS. The fact that the hypothalamic V1a mRNA levels are not altered indicates that these receptors are differentially regulated in different brain regions. This study demonstrates that a permanent deficit in brain angiotensinogen synthesis can alter the functionality of central vasopressinergic system.
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Iliescu R, Campos LA, Schlegel WP, Morano I, Baltatu O, Bader M. Androgen receptor independent cardiovascular action of the antiandrogen flutamide. J Mol Med (Berl) 2003; 81:420-7. [PMID: 12802502 DOI: 10.1007/s00109-003-0449-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2003] [Accepted: 05/13/2003] [Indexed: 10/26/2022]
Abstract
We have previously shown that flutamide (specific antagonist of the androgen receptor) has antihypertensive effects. In the present study we examined the mechanisms of flutamide action in the vasculature. The vascular effects of flutamide were assayed in aortae isolated from male or female Sprague-Dawley rats and from rats or mice lacking a functional androgen receptor ( tfm, testicular feminization mutation). The effect of flutamide on coronary flow was tested in isolated hearts. In addition, male hypertensive rats with tfm mutation were treated with flutamide, and blood pressure was monitored. Flutamide induced a relaxation of rat aortae from all the strains used (maximum relaxation at 10 microM: 51.3+/-5.2% of phenylephrine contraction) and increased the coronary flow. The aortic relaxation to flutamide was abolished by endothelium removal, or by inhibition of nitric oxide synthase, guanylyl cyclase, and tyrosine kinase but not by calmodulin inhibition. Flutamide treatment attenuated the development of hypertension in mouse renin transgenic rats with the tfm mutation. Flutamide produces direct vasodilation by inducing release of NO from the endothelium and causes subsequent activation of soluble guanylyl cyclase in an active androgen receptor independent manner. This response may contribute to the observed antihypertensive actions of flutamide.
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Aranha F, Gomes R, Rutherford C, Rouge A, Alves S, Oliveira M, Campos L, Fernandes M, Nogueira P, Dohmann H. Crit Care 2003; 7:P86. [DOI: 10.1186/cc2282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Dohmann H, Perin E, Silva S, Sousa A, Belém L, Rabichovisky A, Rangel F, Esporcatte R, Campos L, Dohmann H. Crit Care 2003; 7:P3. [DOI: 10.1186/cc2199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Dohman H, Perin E, Sousa A, Silva S, Tinoco C, Esporcatte R, Rangel F, Campos L, Fernandes M, Dohmann H. Crit Care 2003; 7:P12. [DOI: 10.1186/cc2208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Maffei EM, Pompolo SG, Campos LA, Petitpierre E. Sequential FISH analysis with rDNA genes and Ag-NOR banding in the lady beetle Olla v-nigrum (Coleoptera: Coccinellidae). Hereditas 2002; 135:13-8. [PMID: 12043703 DOI: 10.1111/j.1601-5223.2001.00013.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
We have characterized the meiosis of Olla v-nigrum by standard analysis, performed a NOR study using NOR banding, FISH of rDNA genes and sequential FISH/AgNOR analysis, and adapted the FISH methodology to Coccinellidae. The chromosome number determined at metaphase I was n = 9 + Xyp. At zygotene it was possible to identify the sex vesicle which presented a deeply stained heteropycnotic block. Chromosome X is much larger than the y and the two combine, forming a "parachute" in metaphase I. FISH analysis using a probe of rDNA genes 18S, 28S and 5.8S of D. melanogaster was used to map the genes in the sex vesicle. The NOR band showed high gene activity in this region. These results were confirmed using sequential FISH/Ag NOR analysis. The data obtained for Olla v-nigrum agree with the classical hypothesis raised to explain the type of sex chromosome association in a parachute format (Xyp) as being due to the presence of nucleolar material. The chromosome number and parachute configuration during metaphase I in this species agree with the basic karyotype of most Coleopterans. The major adaptation of the FISH method was the simultaneous denaturation and hybridization that permitted preservation of chromosome morphology, an essential factor when the chromosomes are small.
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Gomes R, Aranha F, Campos L, Fernandes M, Nogueira P, Nunes E, Sabino J, Carvalho A, Farina R, Dohmann H. Crit Care 2002; 6:P241. [DOI: 10.1186/cc1709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Gomes R, Aranha F, Mendonça H, Campos L, Tura B, Fernandes M, Nogueira P, Vegni R, Silva D, Dohmann H. Crit Care 2002; 6:P243. [DOI: 10.1186/cc1711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Tavares MG, Ribeiro EH, Campos LA, Barros EG, Oliveira MT. Inheritance pattern of RAPD markers in Melipona quadrifasciata (Hymenoptera: Apidae, Meliponinae). J Hered 2001; 92:279-82. [PMID: 11447247 DOI: 10.1093/jhered/92.3.279] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Melipona quadrifasciata is an important pollinator agent in several regions of Brazil. Data concerning the genetics of this species are scarce in the literature. In this work we used the random amplified polymorphic DNA (RAPD) technique to determine the degree of polymorphism and the inheritance pattern of these molecular markers in this species. Our ultimate goal is to establish tools to be used in the study of the genomic organization of M. quadrifasciata. Genomic DNA from progenies F(1) and BC(1) were assayed with 79 different primers, yielding an average of 6.67 bands and 1.68 polymorphisms per primer. Three types of polymorphisms were detected: band presence/absence, band intensity, and fragment-length polymorphisms. Most of the observed polymorphisms were band presence/absence, typical of RAPD-dominant markers. The number of observed polymorphisms and their segregation in accordance with a Mendelian proportion confirm the importance of this technique for genome analysis of species like M. quadrifasciata that are poorly studied at the genetic level.
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Mendonça F° H, Campos L, Gomes R, Fernandes M, Nogueira P, Sabino J, Aranha F, Silva F° D, Farina R, Dohmann H. Crit Care 2001; 5:P51. [DOI: 10.1186/cc1384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Aranha F, Gomes R, Pinto J, Campos L, Fernandes M, Nogueira P, Azevedo F° C, Vegni R, Carvalho A, Dohmann H. Crit Care 2001; 5:P15. [DOI: 10.1186/cc1348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Morgado J, Nouér S, Porto A, Gomes R, Campos L, Fernandes M, Nogueira P, Drumond L, Rey H, Dohmann H. Crit Care 2001; 5:P66. [DOI: 10.1186/cc1399] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Campos L, Soares L, Fernandes M, Gomes R, Nogueira P, Aranha F, Vegni R, Carvalho A, Silva D, Dohmann H. Crit Care 2001; 5:P70. [DOI: 10.1186/cc1403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Gomes R, Tura B, Campos L, Fernandes M, Nogueira P, Nunes E, Mendonça F° H, Aranha F, Carvalho A, Dohmann H. Crit Care 2001; 5:P88. [DOI: 10.1186/cc1421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Balme A, Hervás M, Campos LA, Sancho J, De la Rosa MA, Navarro JA. A comparative study of the thermal stability of plastocyanin, cytochrome c(6) and Photosystem I in thermophilic and mesophilic cyanobacteria. PHOTOSYNTHESIS RESEARCH 2001; 70:281-9. [PMID: 16252173 DOI: 10.1023/a:1014761524242] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Cytochrome c(6) (Cyt) from the thermophilic cyanobacterium Phormidium laminosum has been purified and characterized. It is a mildly acidic protein, with physicochemical properties very similar to those of plastocyanin (Pc). This is in agreement with the functional interchangeability of the two metalloproteins as electron donors to Photosystem I (PS I). The kinetic analyses of the interaction of Pc and Cyt with Photosystem I show that both metalloproteins reduce PS I with similar efficiencies, according to an oriented collisional kinetic model involving repulsive electrostatic interactions. The thermostability study of the Phormidium Pc/PS I system compared with those from mesophilic cyanobacteria (Synechocystis, Anabaena and Pseudanabaena) reveals that Pc is the partner limiting the thermostability of the Phormidium couple. The cross-reactions between Pc and PS I from different organisms demonstrate not only that Phormidium Pc enhances the stability of the Pc/PS I system using PS I from mesophilic cyanobacteria, but also that Phormidium PS I possesses a higher thermostability than the other photosystems.
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Azevedo F° CF, Aranha FG, Gomes RV, Campos LA, Fernandes MA, Nogueira PM, Dornelles AP, Mendonça F° HTF, Sabino J, Dohmann HF. Early experience of intensive postoperative unit (IPU): percutaneous tracheotomy as the first option after long-term oro-tracheal intubation. Crit Care 2001. [PMCID: PMC3300997 DOI: 10.1186/cc1430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Porto A, Morgado J, Bitencourt M, Gomes R, Campos L, Fernandes M, Nogueira P, Silva S, Rey H, Dohmann H. Crit Care 2001; 5:P11. [DOI: 10.1186/cc1344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Silva Júnior JC, Pompolo S das G, Campos LA, Cruz I. The karyotype of the parasitoid Chelonus insularis Cresson (Hymenoptera, Braconidae, Cheloninae). REVISTA BRASILEIRA DE BIOLOGIA 2000; 60:337-9. [PMID: 10959119 DOI: 10.1590/s0034-71082000000200019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The karyotype of Chelonus insularis (Hymenoptera, Braconidae, Cheloninae) is described. The males show an haploid number of seven chromosomes and the females a diploid number of fourteen chromosomes, confirming haplo-diploid sex determination. Comparisons of these results with karyotypes of other species of the same family were done and a possible mechanism involved in the karyotype evolution of this species is discussed.
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Araújo SM, Pompolo SG, Dergam JA, Campos LA. The B chromosome system of Trypoxylon (Trypargilum) albitarse (Hymenoptera, Sphecidae) 1. Banding analysis. CYTOBIOS 2000; 101:7-13. [PMID: 10697741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Karyotypic analyses of 366 specimens of the solitary wasp Trypoxylon (Trypargilum) albitarse collected from ten populations in the municipalities of Viçosa and Porto Firme (Minas Gerais, Southeastern Brazil), revealed the presence of two morphological types of supernumerary (B) chromosomes. C-banding and fluorochrome banding suggest that the B chromosomes of T. albitarse may have originated from heterochromatin breaks within the standard (A) chromosome complement.
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Collevatti RG, Schoereder JH, Campos LA. Foraging behavior of bee pollinators on the tropical weed Triumfetta semitriloba: flight distance and directionality. REVISTA BRASILEIRA DE BIOLOGIA 2000; 60:29-37. [PMID: 10838921 DOI: 10.1590/s0034-71082000000100005] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We studied flight distance and directionality of bee pollinators on the tropical shrub weed Triumfetta semitriloba Jacq. (Tiliaceae), addressing (1) within- and between-plant movement pattern; (2) distances flown between plants; (3) flight directionality. Flowering plants were distributed in well-delimited clumps, in each of two pasture areas (A1 and A2) and one area of forest gap (A3), in Viçosa, southeastern Brazil. Five solitary bee species, Augochlorella michaelis, Augochloropsis cupreola, Pseudocentron paulistana, Ceratinula sp., Melissodes sexcincta, and two social bee, Plebeia droryana, P. cf. nigriceps were observed. All species moved mainly to the nearest flower on the same individual plant and, in between-plant movements, to the first or second nearest neighbor. All species moved non-randomly, presenting a flight directionality in departures (maintenance of flight direction), but with a high frequency of turn angles. It is suggested that this foraging behavior pattern occurred because of the resource quantity and quality (pollen or nectar), and environmental characteristics such as flower density and resource distribution.
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Magalhaes ML, Campos LA, Souza LC, Almeida FM, Freire HC, Bezerra RC. A case of association of duplication of the urogenital and intestinal tracts. J Pediatr Adolesc Gynecol 1999; 12:165-70. [PMID: 10546911 DOI: 10.1016/s1038-3188(99)00012-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Report of the case of a Caucasian girl, presently 3 years old, who has been followed at the Pediatric Service of the Walter Cantidio Hospital (Federal University of Ceará; Fortaleza, Brazil) since she was 15 days old. At birth she presented a duplication of the bladder, urethra, external genitalia, vagina, colon, and rectum. No cardiac anomalies, bone deformities, or other congenital malformations were detected. When she was 16 months old the child underwent corrective surgery, with rectal vault reconstruction, placing a single and continent anal sphincter in its usual position and resection of the longitudinal vaginal septum, forming a single vaginal cavity. The surgery also resulted in a perineum of normal appearance. Presently, the patient is doing well.
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Campos LA. Hyperplasia of the sublingual glands in adult patients. ORAL SURGERY, ORAL MEDICINE, ORAL PATHOLOGY, ORAL RADIOLOGY, AND ENDODONTICS 1996; 81:584-5. [PMID: 8734707 DOI: 10.1016/s1079-2104(96)80052-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Hyperplasia of the sublingual salivary glands in an entity of unknown cause not previously reported in the literature. The main clinical finding is a unilateral or bilateral painless sublingual enlargement of the sublingual gland without any recognized local or systemic associated factor.
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