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1.
C Junquera M J Azanza P Parra M T Peg J Aisa L M Romero P Garín 《Histology and histopathology》1988,3(2):115-124
The innervation of Rana ridibunda esophagus myenteric plexuses has been studied by the following methods: demonstration of cholinesterase activity; FIF method for catecholamines; immunohistochemistry for VIP, SP and SOM, and conventional electron microscopy. The cholinergic innervation is important in the esophagus wall where, in addition to the well known extrinsic component, there is a rich intrinsic plexus with cells and fibres widely distributed. The esophagus, together with the intestine, are the Rana gut portions where the adrenergic component is more broadly expressed. The adrenergic innervation seems to be almost entirely of extrinsic origin. We have shown that, for the tested peptides, there is an intrinsic innervation represented by VIP, SP and SOM like plexuses. We do not discard nonetheless an extrinsic component. The ultrastructure reveals the morphological characteristics of the enteric neurons as well as the fine inter-relationships between the nervous elements and the functional components of the esophagic wall. 相似文献
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Excess amino acid polymorphism in mitochondrial DNA: contrasts among genes from Drosophila, mice, and humans 总被引:13,自引:3,他引:10
Recent studies of mitochondrial DNA (mtDNA) variation in mammals and
Drosophila have shown an excess of amino acid variation within species
(replacement polymorphism) relative to the number of silent and replacement
differences fixed between species. To examine further this pattern of
nonneutral mtDNA evolution, we present sequence data for the ND3 and ND5
genes from 59 lines of Drosophila melanogaster and 29 lines of D. simulans.
Of interest are the frequency spectra of silent and replacement
polymorphisms, and potential variation among genes and taxa in the
departures from neutral expectations. The Drosophila ND3 and ND5 data show
no significant excess of replacement polymorphism using the
McDonald-Kreitman test. These data are in contrast to significant
departures from neutrality for the ND3 gene in mammals and other genes in
Drosophila mtDNA (cytochrome b and ATPase 6). Pooled across genes, however,
both Drosophila and human mtDNA show very significant excesses of amino
acid polymorphism. Silent polymorphisms at ND5 show a significantly higher
variance in frequency than replacement polymorphisms, and the latter show a
significant skew toward low frequencies (Tajima's D = -1.954). These
patterns are interpreted in light of the nearly neutral theory where mildly
deleterious amino acid haplotypes are observed as ephemeral variants within
species but do not contribute to divergence. The patterns of polymorphism
and divergence at charge-altering amino acid sites are presented for the
Drosophila ND5 gene to examine the evolution of functionally distinct
mutations. Excess charge-altering polymorphism is observed at the carboxyl
terminal and excess charge-altering divergence is detected at the amino
terminal. While the mildly deleterious model fits as a net effect in the
evolution of nonrecombining mitochondrial genomes, these data suggest that
opposing evolutionary pressures may act on different regions of
mitochondrial genes and genomes.
相似文献
4.
Marta Elena álvarez-Argüelles Santiago Melón Maria Luisa Junquera Jose Antonio Boga Laura Villa Sonia Pérez-Castro María de O?a 《PloS one》2013,8(1)
Objective
Human Papillomavirus (HPV) infection in men may produce cancer and other major disorders. Men play an important role in the transmission of the virus and act as a reservoir. The aim of this study was to determine the HPV-genotypes and their prevalence in a group of men attending a Sexually Transmitted Infection service.Patients and Samples
Between July 2002 and June 2011, 1392 balanopreputial, 435 urethral, 123 anal, and 67 condyloma lesions from 1551 men with a mean age of 35.8±11.3 years old (range: 17–87) were collected for HPV-DNA testing.Methods
A fragment of the L1-gene and a fragment of the E6/E7-genes were amplified by PCR. Positive samples were typed by hybridization.Results
The HPV genome was detected in 36.9% (486/1318) balanopreputial and in 24.9% (101/405) urethral (p<0.0001) swabs from 38.1% (538) of 1469 men. Co-infections were present in 5.4% (80/1469) of cases. HPV was found in 43.9% (373/850) of men younger than 35 vs. 31.7% (187/589) of men aged >35. HPV was found in 59.4% (104) of 165 men with lesions (macroscopic or positive peniscopy), and in 22.8% (61/267) without clinical alterations. HPV was also detected in 71.4% (40/56) men with condylomata and in 58.7% (64/109) of men with positive peniscopy.Conclusions
HPV prevalence in men was high and decreased with age. HPV was found more frequently in balanopreputial than in urethral swabs. There was a low rate of co-infections. Low-risk HPV vaccine genotypes were the most recurrent especially in younger. Although HPV has been associated with clinical alterations, it was also found in men without any clinical presentation. Inclusion of men in the national HPV vaccination program may reduce their burden of HPV-related disease and reduce transmission of the virus to non-vaccinated women. 相似文献5.
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Porous polyethylene implants in orbital floor reconstruction 总被引:7,自引:0,他引:7
Villarreal PM Monje F Morillo AJ Junquera LM González C Barbón JJ 《Plastic and reconstructive surgery》2002,109(3):877-85; discussion 886-7
The purpose of this article is to present the authors' experience with the use of porous polyethylene ultrathin sheets for orbital floor reconstruction. Thirty-two patients with orbital floor fractures were treated with porous polyethylene ultrathin sheets. Sixteen cases corresponded to orbitozygomatic fractures, 11 cases corresponded to pure orbital floor fractures, and five corresponded to panfacial fractures. The subciliary approach was used in 15 patients and the transconjunctival approach in nine; another three patients were operated on through a preexisting eyebrow wound, two were operated on with a subtarsal approach, two were operated on through an eyebrow extension of a facial wound, and one patient was operated on through the facial wound. Intraoperatively, all patients received a prophylactic dose of intravenous antibiotics. Postoperatively, 24 patients received amoxicillin clavulanate for 5 to 7 days, two patients received clindamycin, and six patients received no antibiotics. Enophthalmos was corrected in 15 of 24 patients (62.5 percent), and hypoglobus in nine of 11 (82 percent). Diplopia was resolved in 25 of 28 patients (89.3 percent) with preoperative impairment. Extrinsic eye movement impairment was resolved in 25 of 27 patients (92.6 percent). A preoperative visual acuity deficit was present in four patients (12.5 percent) and was resolved in one (from 20/100 to 20/20). Visual acuity improved in one patient (from 20/60 to 20/30). In the other two patients, visual acuity remained altered (from 20/30 to 20/30). One patient (3.1 percent) suffered blindness induced by surgery. Nine of 26 patients (34.6 percent) had residual infraorbital nerve hypesthesia and five (19.2 percent) had residual paresthesias. Postoperatively, epiphora was present in six patients (18.8 percent) and ectropion in five (15.6 percent). Although there was no statistical significance between the surgical approach and the presence of epiphora (p = 0.211) and ectropion (p = 0.422), patients who were treated using the transconjunctival approach suffered reduced ectropion (0 percent) compared with patients treated using the subciliary approach (20 percent). However, patients treated using the transconjunctival approach suffered increased epiphora (22.2 percent) compared with those treated with the subciliary approach (13.3 percent). There were four cases (12.5 percent) of postoperative facial infections. Two of these cases were resolved with systemic antibiotics, one was resolved with bone sequestrum resection, and one patient needed removal of the implant. Orbital infections were related in all cases to titanium osteosynthesis miniplates or skull bone graft. When comparing patients who were treated with and without antibiotics, no statistical differences (p = 0.958) were found relative to the presence of infections. Correction of hypoglobus is technically easier than enophthalmos, because enophthalmic correction requires a wide, deep subperiosteal dissection and implant positioning, posterior to the equator of the globe, with the inherent risk of orbital apex injury. 相似文献
9.
Muñoz-Ubeda M Rodríguez-Pulido A Nogales A Martín-Molina A Aicart E Junquera E 《Biomacromolecules》2010,11(12):3332-3340
Lipoplexes constituted by calf-thymus DNA (CT-DNA) and mixed cationic liposomes consisting of varying proportions of the cationic lipid 3β-[N-(N',N'-dimethylaminoethane)-carbamoyl]cholesterol hydrochloride (DC-Chol) and the zwitterionic lipid, 1,2-dioleoyl-sn-glycero-3-phosphoetanolamine (DOPE) have been analyzed by means of electrophoretic mobility, SAXS, and fluorescence anisotropy experiments, as well as by theoretically calculated phase diagrams. Both experimental and theoretical studies have been run at several liposome and lipoplex compositions, defined in terms of cationic lipid molar fraction, α, and either the mass or charge ratios of the lipoplex, respectively. The experimental electrochemical results indicate that DC-Chol/DOPE liposomes, with a mean hydrodynamic diameter of around (120 ± 10) nm, compact and condense DNA fragments at their cationic surfaces by means of a strong entropically driven electrostatic interaction. Furthermore, the positive charges of cationic liposomes are compensated by the negative charges of DNA phosphate groups at the isoneutrality L/D ratio, (L/D)(?), which decreases with the cationic lipid content of the mixed liposome, for a given DNA concentration. This inversion of sign process has been also studied by means of the phase diagrams calculated with the theoretical model, which confirms all the experimental results. SAXS diffractograms, run at several lipoplex compositions, reveal that, irrespectively of the lipoplex charge ratio, DC-Chol/DOPE-DNA lipoplexes show a lamellar structure, L(α), when the cationic lipid content on the mixed liposomes α ≥ 0.4, while for a lower content (α = 0.2) the lipoplexes show an inverted hexagonal structure, H(II), usually related with improved cell transfection efficiency. A similar conclusion is reached from fluorescence anisotropy results, which indicate that the fluidity on liposome and lipoplexes membrane, also related with better transfection results, increases as long as the cationic lipid content decreases. 相似文献
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