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Brancalhão RMC, Torquato EFB, Fernandez MA. Cytopathology of Bombyx mori (Lepidoptera: Bombycidae) silk gland caused by multiple nucleopolyhedrovirus. GENETICS AND MOLECULAR RESEARCH 2009; 8:162-72. [PMID: 19283683 DOI: 10.4238/vol8-1gmr545] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
A multiple nucleopolyhedrovirus previously isolated from infected Bombyx mori L. larvae (BmMNPV) in Paraná state, Brazil, was inoculated into B. mori larvae to examine susceptibility and cytopathology in silk gland cells. The anterior, middle and posterior silk glands were removed from the infected silkworm at different times post-inoculation and processed for cytopathology studies by light and transmission electron microscopy. BmMNPV infection was only detected at 72 h post-inoculation in cells of the middle and posterior silk glands. No sign of infection was found in the anterior silk gland. Cytopathological characteristics were similar to those found in other target tissues; initially, they consisted of nuclear hypertrophy and the formation of virogenic stroma (viroplasm), in which the progeny virions are produced. The virions are then enveloped and occluded in protein crystal structures, the polyhedra. After viral replication, cells undergo lysis and release a great number of BmMNPV polyhedra into the hemocoele. Histopathology showed early infection foci in regions surrounding trachea insertions, demonstrating that trachea is an infection-spreading organ in the insect body. Trachea penetrates the middle and posterior silk gland basal lamina, considered a barrier to virus, facilitating the penetration of budded virus. The anterior silk gland does not have tracheal insertions into the basal lamina, which reduces budded virus infection. Tracheal branches provide a conduit for non-occluded virions (budded virus) to pass through the basal lamina barrier and disseminate BmMNPV in the silkworm silk gland.
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Bravo JP, Silva JLC, Munhoz REF, Fernandez MA. DNA barcode information for the sugar cane moth borer Diatraea saccharalis. GENETICS AND MOLECULAR RESEARCH 2008; 7:741-8. [PMID: 18767242 DOI: 10.4238/vol7-3gmr470] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We reviewed the use and relevance of barcodes for insect studies and investigated the barcode sequence of Diatraea saccharalis. This sequence has a high level of homology (99%) with the barcode sequence of the Crambidae (Lepidoptera). The sequence data can be used to construct relationships between species, allowing a multidisciplinary approach for taxonomy, which includes morphological, molecular and distribution data, all of which are essential for the understanding of biodiversity. The D. saccharalis barcode is a previously undescribed sequence that could be used to analyze Lepidoptera biology.
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Gimenes F, Takeda KI, Fiorini A, Gouveia FS, Fernandez MA. Intrinsically bent DNA in replication origins and gene promoters. GENETICS AND MOLECULAR RESEARCH 2008; 7:549-58. [PMID: 18752180 DOI: 10.4238/vol7-2gmr461] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Intrinsically bent DNA is an alternative conformation of the DNA molecule caused by the presence of dA/dT tracts, 2 to 6 bp long, in a helical turn phase DNA or with multiple intervals of 10 to 11 bp. Other than flexibility, intrinsic bending sites induce DNA curvature in particular chromosome regions such as replication origins and promoters. Intrinsically bent DNA sites are important in initiating DNA replication, and are sometimes found near to regions associated with the nuclear matrix. Many methods have been developed to localize bent sites, for example, circular permutation, computational analysis, and atomic force microscopy. This review discusses intrinsically bent DNA sites associated with replication origins and gene promoter regions in prokaryote and eukaryote cells. We also describe methods for identifying bent DNA sites for circular permutation and computational analysis.
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Gimenes F, Gouveia FDS, Fiorini A, Fernandez MA. Intrinsic bent DNA sites in the chromosomal replication origin of Xylella fastidiosa 9a5c. Braz J Med Biol Res 2008; 41:295-304. [PMID: 18392452 DOI: 10.1590/s0100-879x2008000400007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2007] [Accepted: 03/05/2008] [Indexed: 11/21/2022] Open
Abstract
The features of the nucleotide sequences in both replication and promoter regions have been investigated in many organisms. Intrinsically bent DNA sites associated with transcription have been described in several prokaryotic organisms. The aim of the present study was to investigate intrinsic bent DNA sites in the segment that holds the chromosomal replication origin, oriC, of Xylella fastidiosa 9a5c. Electrophoretic behavior analyses, as well as in silico analyses of both the 2-D projection and helical parameters, were performed. The chromosomal segment analyzed contains the initial sequence of the rpmH gene, an intergenic region, the dnaA gene, the oriC sequence, and the 5' partial sequence of the dnaN gene. The analysis revealed fragments with reduced electrophoretic mobility, which indicates the presence of curved DNA segments. The analysis of the helical parameter ENDS ratio revealed three bent DNA sites (b1, b2, and b3) located in the rpmH-dnaA intergenic region, the dnaA gene, and the oriC 5' end, respectively. The chromosomal segment of X. fastidiosa analyzed here is rich in phased AT tracts and in CAnT motifs. The 2-D projection indicated a segment whose structure was determined by the cumulative effect of all bent DNA sites. Further, the in silico analysis of the three different bacterial oriC sequences indicated similar negative roll and twist >34.00 degrees values. The DnaA box sequences, and other motifs in them, may be associated with the intrinsic DNA curvature.
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Fiorini A, Gouveia FDS, Fernandez MA. Scaffold/Matrix Attachment Regions and intrinsic DNA curvature. BIOCHEMISTRY (MOSCOW) 2006; 71:481-8. [PMID: 16732725 DOI: 10.1134/s0006297906050038] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recent approaches have failed to detect nucleotide sequence motifs in Scaffold/Matrix Attachment Regions (S/MARs). The lack of any known motifs, together with the confirmation that some S/MARs are not associated to any peculiar sequence, indicates that some structural elements, such as DNA curvature, have a role in chromatin organization and on their efficiency in protein binding. Similar to DNA curvature, S/MARs are located close to promoters, replication origins, and multiple nuclear processes like recombination and breakpoint sites. The chromatin structure in these regulatory regions is important to chromosome organization for accurate regulation of nuclear processes. In this article we review the biological importance of the co-localization between bent DNA sites and S/MARs.
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Fernandez MA, de Luca Rebello Wagener A, Limaverde AM, Scofield AL, Pinheiro FM, Rodrigues E. Imposex and surface sediment speciation: a combined approach to evaluate organotin contamination in Guanabara Bay, Rio de Janeiro, Brazil. MARINE ENVIRONMENTAL RESEARCH 2005; 59:435-452. [PMID: 15603768 DOI: 10.1016/j.marenvres.2004.07.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2003] [Revised: 07/24/2004] [Accepted: 07/24/2004] [Indexed: 05/24/2023]
Abstract
An integrated biological-chemical survey of organotin compounds was carried out in Guanabara Bay, the second most important Brazilian harbor complex. The biological survey revealed high levels of imposex in Stramonita haemastoma populations. Inside the bay values of relative penis length index from 42.7 to 107.6 and vas deferens sequence index from III to VI were found, while organisms collected outside the bay had values ranging from <0.1 to 35.2 and from 0 to II. None of the females sampled inside the bay were normal and imposex was found in all stations. Surface sediments in the bay are contaminated by tributyltin (10-522 ng/g d.w.) and triphenyltin (<3.9-39.4 ng/g d.w.) with greater concentrations close to shipyards and marinas. The observed predominance of parent compounds (TBT and TPT) is commonly found when recent inputs occur, but may also indicate slow degradation processes in the anoxic conditions of these sediments. To our knowledge, this is the first report of a combined imposex-sediment approach to evaluate organotin contamination in marine environments of South America, and also the first report of TPT detection in environmental matrices in this region.
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Saenz MT, Tornos MP, Alvarez A, Fernandez MA, García MD. Antibacterial activity of essential oils of Pimenta racemosa var. terebinthina and Pimenta racemosa var. grisea. Fitoterapia 2004; 75:599-602. [PMID: 15351118 DOI: 10.1016/j.fitote.2004.06.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2004] [Accepted: 06/03/2004] [Indexed: 10/26/2022]
Abstract
The antibacterial activity of essential oils of Pimenta racemosa var. terebinthina and P. racemosa var. grisea was determined against Gram (+) and Gram (-) bacteria. P. racemosa var. grisea demonstrated a more pronounced activity. These data would indicate the potential usefulness of the variety grisea as a microbiostatic, antiseptic or disinfectant agent.
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Thiengo SC, Fernandez MA, Boaventura MF, Grault CE, Silva HF, Mattos AC, Santos SB. Freshwater snails and schistosomiasis mansoni in the State of Rio de Janeiro, Brazil: I-- Metropolitan mesoregion. Mem Inst Oswaldo Cruz 2002; 96 Suppl:177-84. [PMID: 11586447 DOI: 10.1590/s0074-02762001000900028] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In order to elaborate a planorbid chart of the State of Rio de Janeiro a survey of freshwater gastropods in the Metropolitan Mesoregion of this State was performed and revealed the occurrence of 20 species: Antillorbis nordestensis (Lucena, 1954); Biomphalaria glabrata (Say, 1818); Biomphalaria schrammi (Crosse, 1864); Biomphalaria straminea (Dunker, 1848); Biomphalaria tenagophila (Orbigny, 1835); Burnupia sp.; Drepanotrema anatinum (Orbigny, 1835); Drepanotrema cimex (Moricand, 1839); Drepanotrema lucidum (Pfeiffer, 1839); Ferrissia sp.; Gundlachia ticaga (Marcus & Marcus, 1962); Heleobia davisi Silva & Thomé, 1985; Lymnaea columella Say, 1817; Melanoides tuberculatus (Müller, 1774); Physa cubensis Pfeiffer, 1839; Physa marmorata Guilding, 1828; Pomacea sp.; Pomacea canaliculata (Lamarck, 1822); Pomacea lineata (Spix, 1827) and Pomacea sordida (Swainson, 1823). Among the planorbid species B. tenagophila was the most frequent, occurring in all municipalities surveyed. The present study extends the distribution of B. straminea in the State of Rio de Janeiro and reports new records for A. nordestensis, B. schrammi, G. ticaga, H. davisi and the genera Burnupia and Ferrissia. An account about the current transmission areas of schistosomiasis mansoni in this Mesoregion is presented as well.
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Fernandez MA, Pieri OS. Infection by Schistosoma mansoni Sambon 1907 in the first four months of life of Biomphalaria straminea (Dunker, 1848) in Brazil. Mem Inst Oswaldo Cruz 2002; 96 Suppl:185-92. [PMID: 11586448 DOI: 10.1590/s0074-02762001000900029] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Compatibility between Schistosoma mansoni and Biomphalaria straminea when exposed to the parasite on the first four months of age was assessed for five parasitological aspects: indices of infection and mortality, duration of precercarial and cercarial periods, and rate of cercarial emission. Infections were made on molluscs from laboratory colonies, at the following ages: 8, 13, 18, 21, 53, 83 and 114 days. Two B. straminea colonies were used (Camorim, PE and Picos, PI), and one B. glabrata colony (Ressaca, MG) was used as control. The main results are as follows: (I) infection was significantly associated with mollusc age, being proportionally higher in sexually immature than in mature molluscs for the three colonies; (II) for B. straminea from Camorim, mortality did not differ significantly between infected and non-infected snails; for B. straminea from Picos significantly more deaths occurred among infected than among non-infected snails, while the opposite was observed for B. glabrata from Ressaca; (III) for the three colonies, the precercarial period was significantly shorter for immature molluscs than for mature ones; (IV) the duration of the cercarial period was extremely variable for the three colonies; (V) sexual maturity did not influence cercarial emission for the three colonies.
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Fiorini A, Basso LR, Paçó-Larson ML, Fernandez MA. Mapping of intrinsic bent DNA sites in the upstream region of DNA puff BhC4-1 amplified gene. J Cell Biochem 2001; 83:1-13. [PMID: 11500949 DOI: 10.1002/jcb.1188] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We have identified bent DNA sites in the distal and proximal DNA puff BhC4-1 amplified gene promoter region of Bradysia hygida. The 2D modeling of the 3D DNA path and the ENDS ratio values calculated in this promoter region resulted in the identification of ten pronounced bent sites named BhC4B - 9 to + 1. The 1847 bp fragment (- 3697 to - 1850) in relation to the transcription start site shows multiple bending sites, BhC4B - 9 to BhC4B - 4, with periodicity approximately 300 bp. The analysis of the other identified bent region, starting at position - 957, reveals that the BhC4B + 1 bent site colocalizes with the putative BhC4-1 minimal promoter. The sequence analysis of bent site BhC4B - 4 shows a distribution of dA*dT at approximately 10 bp intervals between the middle of each tract, but intervals with more than one turn, approximately 20 bp, two helix turns, were detected in the other bent sites described here. The bent sites BhC4B - 6 and BhC4B - 4, contain two consensus sequences, with 60 bp each. The apparent molecular weight of fragments in the BhC4-1 promoter region were estimated in agarose gels and compared with the data obtained in polyacrylamide gels without and with ethidium bromide. The mobility reduction ratios (R-values) were determined, and a high R-value, 1.80, for a 1215 bp fragment in the distal promoter region and a 1.23 significant R-value for a 662 bp fragment in the proximal segment were found. To further analyze the predicted bent DNA sites in these fragments, the 2D trajectories of the 3D DNA path and other parameters, AT percentage, roll angle, ENDS ratio and DeltaG, were determined. The role of these bent sites in the BhC4-1 transcription regulation is discussed.
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Fernandez MA, Thiengo SC, Boaventura MF. [Freshwater snails of the Campus of Manguinhos, Oswaldo Cruz Foundation, Rio de Janeiro, RJ]. Rev Soc Bras Med Trop 2001; 34:279-82. [PMID: 11460215 DOI: 10.1590/s0037-86822001000300009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A survey of freshwater gastropods of the Campus of Manguinhos, Fundação Oswaldo Cruz, Rio de Janeiro, was carried out during the last two years aiming to compare the current species with those found at the beginning of this century. Among 18 breeding sites in 880,000m2 of the surveyed area, 13 showed the following species: Antillorbis nordestensis; Biomphalaria glabrata; Biomphalaria straminea; Lymnaea columella; Melanoides tuberculatus; Physa cubensis; Pomacea glauca and Pomacea lineata. Notably, Biomphalaria tenagophila reported by Lutz in 1918, had disappeared and B. straminea and the Asiatic thiarid M. tuberculatus had been introduced. No specimens infected with Schistosoma mansoni were found.
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Borges AR, Gaspar VP, Fernandez MA. Unequal X chromosomes in Bradysia hygida (Diptera:Sciaridae) females: karyotype assembly and morphometric analysis. Genetica 2001; 108:101-5. [PMID: 11145415 DOI: 10.1023/a:1004016809267] [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: 11/12/2022]
Abstract
The mitotic chromosomes of Bradysia hygida (Diptera:Sciaridae) neuroblast cells are described together with their morphometric data. Giemsa-stained neuroblast chromosomes from female and male larvae confirm the chromosome number of this species, 2n = 8 (XX) and 2n = 7 (XO), respectively. The karyotype assembly reveals two metacentric autosomic pairs, the A and B chromosomes; a subtelocentric, the C chromosome, the smallest one; and a sexual unequal metacentric pair, X chromosome, in female karyotype and a one sexual metacentric X chromosome in male. The implications of the unequal X chromosome pair are discussed.
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Lindberg J, Fernandez MA, Ropp JD, Hamm-Alvarez SF. Nocodazole treatment of CV-1 cells enhances nuclear/perinuclear accumulation of lipid-DNA complexes and increases gene expression. Pharm Res 2001; 18:246-9. [PMID: 11405299 DOI: 10.1023/a:1011001022570] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Beutler E, Gelbart T, Lee P, Trevino R, Fernandez MA, Fairbanks VF. Molecular characterization of a case of atransferrinemia. Blood 2000; 96:4071-4. [PMID: 11110675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Hereditary atransferrinemia is a rare but instructive disorder that has previously been reported in only 8 patients in 6 families. It is characterized by microcytic anemia and by iron loading, and can be treated effectively by plasma infusions. We now report the first case known in the United States. We determined the sequences flanking the exons of the human transferrin gene and sequenced all of the exons and some of the flanking regions of the patient's DNA and that of her parents. The patient's DNA revealed a 10-base pair (bp) deletion, followed by a 9-bp insertion of a duplicated sequence. There was also a G-->C transversion at complementary DNA (cDNA) nt 1429, predicting that a proline was substituted for the alanine in amino acid position 477 (Ala 477 Pro). The latter mutation occurs at an evolutionarily highly conserved site; 704 control alleles were screened and this point mutation was not found. Each of the patient's transferrin genes contains one mutation, ie, the patient is a compound heterozygote for these mutations, because one was found in each of her parents. In addition to these mutations, which we regard to be causative in the patient's atransferrinemia, a silent polymorphism at cDNA 1572 G-->C was found in exon 13 as well as 2 previously unreported polymorphisms at IVS8 + 62 c-->t and IVS14-4 c-->a. The mutation in nt 1572 and that in intron 8 were common in the general population; the intron 14 mutation is rare.
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Oyelese Y, Spong C, Fernandez MA, McLaren RA. Second trimester low-lying placenta and in-vitro fertilization? Exclude vasa previa. THE JOURNAL OF MATERNAL-FETAL MEDICINE 2000; 9:370-2. [PMID: 11243298 DOI: 10.1002/1520-6661(200011/12)9:6<370::aid-mfm1011>3.0.co;2-e] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We report the prenatal diagnosis of vasa previa using transvaginal sonography and color Doppler. This case supports the previously reported association of vasa previa with second trimester low-lying placentas and in-vitro fertilization. Sonographic examination for vasa previa should be considered in pregnancies with low-lying placentas and those resulting from in-vitro fertilization.
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Cabrera T, Salinero J, Fernandez MA, Garrido A, Esquivias J, Garrido F. High frequency of altered HLA class I phenotypes in laryngeal carcinomas. Hum Immunol 2000; 61:499-506. [PMID: 10773352 DOI: 10.1016/s0198-8859(00)00097-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The exact frequency of HLA class I losses in human tumors is unknown. We have previously shown that primary breast and colorectal carcinomas frequently lose HLA class I molecules (88% and 73%, respectively). Now we report that this phenomenon is also a frequent event in laryngeal carcinomas. Of a total of 76 laryngeal carcinomas analyzed, 66% of the tumors showed an alteration in HLA class I phenotype. These altered HLA phenotypes were classified as total HLA loss (10.52%) (phenotype I); HLA-A locus-specific loss (13.15%) (phenotype IIIa); HLA-B locus-specific loss (10.52%) (phenotype IIIb); HLA allelic loss (27.63%) (phenotype IV); and HLA-A and B locus loss (3.9%). Comparison of histopathological parameters with HLA expression showed that poorly differentiated tumors had the lowest levels of HLA class I expression (p < 0.05).
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Fernandez MA, Mani SA, Rangarajan PN, Seshagiri PB. Sperm-mediated gene transfer into oocytes of the golden hamster: assessment of sperm function. INDIAN JOURNAL OF EXPERIMENTAL BIOLOGY 1999; 37:1085-92. [PMID: 10783740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
The possibility of sperm as a vehicle to deliver foreign DNA to oocytes was tested in hamsters. Epididymal spermatozoa, incubated with linearized plasmid DNA encoding ovine growth hormone (pCMXoGH), showed a spontaneous tendency to interact with DNA. Kinetics of sperm uptake of DNA was determined by using [32P]-labeled DNA. Spermatozoa took up the added DNA by 15-30 min and the uptake was inhibited by human seminal fluid in a dose dependent manner. Addition of DNA did not affect the functional competence of spermatozoa, in terms of their ability to undergo capacitation and acrosome reaction (34.5% +/- 2.2 vs 35% +/- 1.5). The fertilizing ability of DNA treated-spermatozoa from hamsters and humans was assessed by zona-free hamster egg penetration assay. Number of sperm penetrated per oocyte were 23 +/- 4.5 and 1.4 +/- 1.3 for hamster and human spermatozoa, respectively. Penetrated oocytes harbored sperm-treated DNA both with hamster (30.2 cpm/oocyte) and human (19.2 cpm/oocyte) spermatozoa. These results show that the hamster and human spermatozoa have a strong tendency to interact with exogenous (foreign) DNA and are able to transfer DNA to oocytes. Sperm may be used as a vector for DNA transfer and this approach has potential in the production of transgenic animals.
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Thiengo SC, Fernandez MA, Boaventura MF, Stortti MA. A survey of freshwater gastropods in the Microrregião Serrana of the state of Rio de Janeiro, Brazil. Mem Inst Oswaldo Cruz 1999; 93 Suppl 1:233-4. [PMID: 9921357 DOI: 10.1590/s0074-02761998000700041] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Fernandez MA, Alonso C, Gonzalez MJ, Hernandez LM. Occurrence of organochlorine insecticides, PCBs and PCB congeners in waters and sediments of the Ebro River (Spain). CHEMOSPHERE 1999; 38:33-43. [PMID: 10903089 DOI: 10.1016/s0045-6535(98)00167-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Organochlorine insecticides and poychlorinated biphenyls (PCBs) were measured in water and sediment samples taken from thirteen sites along the Ebro River (Spain), the most agricultural and industrial basin in the North of the Iberian Peninsula. Concentrations of 10 insecticides, PCBs and 13 PCB congeners were determined: grouping all chemicals by structural affinity, these can be arranged in descending order as follow: PCBs > total DDT > total cyclodiene insecticides > total HCH. Higher levels of organochlorine pollutants were detected in sediments from the middle and lower parts of the stream where are located the main important inputs in Ebro River.
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Ni J, Fernandez MA, Danielsson L, Chillakuru RA, Zhang J, Grubb A, Su J, Gentz R, Abrahamson M. Cystatin F is a glycosylated human low molecular weight cysteine proteinase inhibitor. J Biol Chem 1998; 273:24797-804. [PMID: 9733783 DOI: 10.1074/jbc.273.38.24797] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
A previously undescribed human member of the cystatin superfamily called cystatin F has been identified by expressed sequence tag sequencing in human cDNA libraries. A full-length cDNA clone was obtained from a library made from mRNA of CD34-depleted cord blood cells. The sequence of the cDNA contained an open reading frame encoding a putative 19-residue signal peptide and a mature protein of 126 amino acids with two disulfide bridges and enzyme-binding motifs homologous to those of Family 2 cystatins. Unlike other human cystatins, cystatin F has 2 additional Cys residues, indicating the presence of an extra disulfide bridge stabilizing the N-terminal region of the molecule. Recombinant cystatin F was produced in a baculovirus expression system and characterized. The mature recombinant protein processed by insect cells had an N-terminal segment 7 residues longer than that of cystatin C and displayed reversible inhibition of papain and cathepsin L (Ki = 1.1 and 0.31 nM, respectively), but not cathepsin B. Like cystatin E/M, cystatin F is a glycoprotein, carrying two N-linked carbohydrate chains at positions 36 and 88. An immunoassay for quantification of cystatin F showed that blood contains low levels of the inhibitor (0.9 ng/ml). Six B cell lines in culture secreted barely detectable amounts of cystatin F, but several T cell lines and especially one myeloid cell line secreted significant amounts of the inhibitor. Northern blot analysis revealed that the cystatin F gene is primarily expressed in peripheral blood cells and spleen. Tissue expression clearly different from that of the ubiquitous inhibitor, cystatin C, was also indicated by a high incidence of cystatin F clones in cDNA libraries from dendritic and T cells, but no clones identified by expressed sequence tag sequencing in several B cell libraries and in >600 libraries from other human tissues and cells.
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Cabrera T, Collado A, Fernandez MA, Ferron A, Sancho J, Ruiz-Cabello F, Garrido F. High frequency of altered HLA class I phenotypes in invasive colorectal carcinomas. TISSUE ANTIGENS 1998; 52:114-23. [PMID: 9756399 DOI: 10.1111/j.1399-0039.1998.tb02274.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We analyzed the expression of HLA class I antigens in 78 tumor tissue samples obtained from patients diagnosed as having colorectal carcinomas. A broad panel of mAbs defining HLA monomorphic, locus-specific and allele-specific determinants was used. In addition, an antibody defining HLA-C locus-specific determinant (L31) was also tested. Previous reports on these tumors indicated HLA class I losses of 30 to 40%. At least 73% of the patients in the present study had a detectable HLA class I alteration. These altered HLA phenotypes were classified as total HLA loss (18%) (phenotype I); HLA-A locus-specific loss (9%) (phenotype IIIa); HLA-B locus-specific loss (8%) (phenotype IIIb); HLA-A and B locus losses (2%) and HLA allelic losses (36%) (phenotype IV). We found no HLA-C locus losses. Autologous peripheral blood lymphocyte HLA class I typing was always necessary to define phenotype IV. We also studied the CD3 zeta chain in tumor tissues to correlate possible changes in the CD3 signal transduction pathway with HLA alterations. The CD3 ratio was frequently altered, but this alteration could not be correlated with tumor HLA phenotypes. The high frequency of HLA class I losses in colorectal carcinomas suggests that this finding is a widespread phenomenon and may be required to escape T-cell recognition. It remains to be determined whether HLA expression is "normal" in the rest of the 27% of our patients.
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Toledo F, Baron B, Fernandez MA, Lachagès AM, Mayau V, Buttin G, Debatisse M. oriGNAI3: a narrow zone of preferential replication initiation in mammalian cells identified by 2D gel and competitive PCR replicon mapping techniques. Nucleic Acids Res 1998; 26:2313-21. [PMID: 9580680 PMCID: PMC147574 DOI: 10.1093/nar/26.10.2313] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The nature of mammalian origins of DNA replication remains controversial and this is primarily because two-dimensional gel replicon mapping techniques have identified broad zones of replication initiation whereas several other techniques, such as quantitative PCR, have disclosed more discrete sites of initiation at the same chromosomal loci. In this report we analyze the replication of an amplified genomic region encompassing the 3'-end of the GNAI3 gene, the entire GNAT2 gene and the intergenic region between them in exponentially growing Chinese hamster fibroblasts. These cells express GNAI3 but not GNAT2 . The replication pattern was first analyzed by two-dimensional neutral-alkaline gel electrophoresis. Surprisingly, the results revealed a small preferential zone of replication initiation, of at most 1.7 kb, located in a limited part of the GNAI3 - GNAT2 intergenic region. Mapping of this initiation zone was then confirmed by quantitative PCR. The agreement between the two techniques exploited here strengthens the hypothesis that preferred sites of replication initiation do exist in mammalian genomes.
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Trujillo MH, Guerrero J, Fragachan C, Fernandez MA. Pharmacologic antidotes in critical care medicine: a practical guide for drug administration. Crit Care Med 1998; 26:377-91. [PMID: 9468179 DOI: 10.1097/00003246-199802000-00044] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Montero A, Fernandez MA, Cohen JE, Luraghi MR, Sen L. Prolactin levels in the cerebrospinal fluid of patients with HIV infection and AIDS. Neurol Res 1998; 20:2-4. [PMID: 9471094 DOI: 10.1080/01616412.1998.11740475] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The objective of this study was to assess the levels of prolactin (PRL) in cerebrospinal fluid (CSF) of HIV-infected patients with regard to nonHIV-infected patients, and to assess the levels of prolactin in the CSF of HIV-infected patients with and without neurological HIV-involvement. Seventeen HIV-infected patients with different degrees of immunological and neurological involvement were studied. A second group of six HIV-seronegative patients with varying clinical conditions requiring lumbar punctures were included as controls. CSF was collected from patients and controls. Patients were studied neurologically and neuropsychologically, and computed tomography of the brain were performed. They were staged according to CDC clinical classification for HIV infection, and on the basis of tomographic findings into one of five stages. An additional classification for neurological involvement in AIDS was used. CD4+ cell counts, CSF studies, serum-prolactin levels and CSF-prolactin levels were performed as principal laboratory tests. CSF PRL concentrations were significantly higher in the HIV-infected group (n = 17) than the nonHIV infected control group (n = 6) (mean +/- s.d.; 5.77 +/- 2.22 vs. 3.53 +/- 0.69 x 10(-6) g l-1, respectively; p = 0.009, Mann-Whitney U-test). Moreover, even CSF-PRL concentration was higher in HIV-infected patients without cognitive impairment (stage 0 of the clinical classification), (n = 12) in comparison with nonHIV infected controls (n = 6) (mean +/- s.d.; 5.51 +/- 2.31 vs. 3.53 +/- 0.69 x 10(-1) g l-1, respectively; p = 0.028, Mann-Whitney U-test). There was a good correlation between serum and CSF-PRL levels in HIV-infected patients when measured by the Spearman Rank Test (rs = 0.773; p = 0.005). PRL raised serum levels were found in 4 out of 13 patients (30.73%). We conclude that higher levels of CSF-PRL are more frequently found in HIV-infected patients in comparison to uninfected controls. High levels of circulating PRL were also found in HIV-infected patients corroborating results from other work. A good correlation coefficient was found between circulating and CSF-PRL levels in HIV-infected patients, suggesting that disruption of the blood-brain barrier might account for a possible pathogenic mechanism.
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Fernandez MA, Baron B, Prigent M, Toledo F, Buttin G, Debatisse M. Matrix attachment regions and transcription units in a polygenic mammalian locus overlapping two isochores. J Cell Biochem 1997; 67:541-51. [PMID: 9383712 DOI: 10.1002/(sici)1097-4644(19971215)67:4<541::aid-jcb11>3.0.co;2-c] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Eukaryotic chromosomes are ponctuated by specialized DNA sequences (MARs) characterized by their ability to bind the network of nonhistone proteins that form the nuclear matrix or scaffold. We previously described an amplifiable cluster of genes with different tissue-specific expression patterns, located on Chinese hamster chromosome 1q. This model is especially appropriate to study the relationships between MARs and transcription units. We show here that four attachment regions, with sequences exhibiting motifs specific to MARs, are present within the 100 kb of screened DNA. Three of them are relatively short sequences localized in intergenic regions. The last one extends over one of the transcription units and contains a region previously identified as a recombination hot spot. Moreover, the analysis of a DNA sequence extending over some 50 Kb of this region and spanning at least four genes, disclosed a strikingly sharp change in G + C content. This strongly suggests that the studied region contains the boundary of two isochores. We propose that the frequency and the size of MARs are correlated to their localization in G + C rich or poor domains.
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