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1.
Various traditional mammaplasty techniques have been suggested for unilateral breast reduction, and an inverted-T incision is still the most popular approach. However, unilaterally performed traditional techniques can rarely provide long-lasting symmetry because the operated and the unoperated breasts react differently to aging, weight changes, and pregnancy. Considerable residual scarring, interference with clinical and mammographic evaluation, and limited versatility are all major drawbacks of traditional procedures. We have performed unilateral mammaplasties on 47 patients with various types of congenital and acquired asymmetries, reducing and sculpturing the breast from the undersurface by means of minimal incisions, always avoiding horizontal scarring in the inframammary crease. Through a vertical infra-areolar incision, the breast is completely detached from the underlying pectoralis fascia and hooked up, thus completely exposing the undersurface of the mammary cone. The breast can thereafter be reshaped according to the size and shape of the contralateral breast by means of a discoid resection and/or selective sectoral removal of excessive subcutaneous tissues; modifications of the basic discoid resection can increase anterior projection of the new breast mound and can change the inclination of the anteroposterior breast axis on the anterior chest wall both on the horizontal and vertical planes. The results show that if criteria for patient selection are carefully respected, the procedure can provide long-lasting symmetry with minimal residual scarring and fully preserve the breast anatomy, function, and vascularization.  相似文献   
2.
Contact sensitization to components of the urushiol oils of poison oak and poison ivy appears to require covalent bond formation between the o-quinones derived from urushiol catechols and nucleophilic groups on proteins. Previous studies using a murine delayed hypersensitivity model demonstrated that 5-methyl-3-pentadecylcatechol (5-Me-PDC) is an epicutaneous tolerogen to the parent compound and a weak sensitizer to itself. To investigate further the structural requirements for sensitization vs suppression, 5,6-dimethyl-3-pentadecylcatechol (5,6-di-Me-PDC) and 4,5,6-trimethylpentadecylcatechol (4,5,6-tri-Me-PDC) were synthesized. The former compound is blocked at both preferred sites for covalent bond formation and the latter is completely blocked towards conjugate addition reactions. These compounds were tested for sensitizing and suppressive ability. Epicutaneous application of both analogs suppressed subsequent induction of sensitization to 3-pentadecylcatechol (PDC) and 3-heptadecylcatechol (HDC). Lymph node cells from animals treated with 5,6-di-Me-PDC could transfer suppression. The dimethyl analog, 5,6-di-Me-PDC, but not the trimethyl analog also exhibited weak sensitizing capacity. The urushiol analogs 5-pentadecylresorcinol (PDR) and 3-heptadecylveratrole (HDV) which cannot form o-quinones were found to be ineffective sensitizers as well. HDV in addition produced no blastogenesis in draining lymph nodes whereas lymph node cell proliferation induced by 4,5,6-tri-Me-PDC followed the same kinetics as previously observed for HDC. PDR elicited weak proliferation with a different time course. These and previous studies indicate that blocking the C5-position on the catechol ring favors the induction of suppression, although some sensitizing capacity may be retained. Covalent bond formation may not be necessary for the induction of active suppressor cell populations.  相似文献   
3.
Summary The present study has been carried out to determine if glycine, an allosteric modulator of NMDA receptor, is involved in the vascular effect induced by the activation of the CNS NMDA receptors.Icv NMDA (from 0.01 to 1µg/rat in the 3rd ventricle) caused a significant increase in arterial blood pressure in conscious freely moving rats. Moreover, the hypertension was associated with behavioural modifications (jumping, rearing, teething and running). Glycine pretreatment (1 and 10µg/raticv), significantly increased the NMDA hypertension. Glycine alone did not cause any arterial blood pressure modification while it induced a slight sedation. HA-966 (an antagonist of the glycine site on NMDA receptor) administration (1–10µg/raticv 5 min before glycine) significantly antagonized the glycine effects on NMDA hypertension.Alone HA-966 neither modified arterial blood pressure nor antagonized NMDA hypertension. In conclusion, our investigations confirm NMDA receptor involvement in cardiovascular function and they demonstrate thatin vivo glycine positively modulates NMDA receptors.  相似文献   
4.
Babesia caballi and Theileria equi are widely recognized as causative agents of equine pirolasmosis (EP), an acute, sub‐acute, and chronic disease of equines, with relevant economic impact on horse trade worldwide. Although several studies on EP prevalence from central Italy have been published, data on ticks responsible for its transmission are still lacking. In this study, we identified a potential competent vector, investigating main features of its ecology together with EP infection rates. A two‐year sampling of questing ticks was carried out for the first time in Italy in an area known for high EP prevalence in horse sera, detecting the association between Rhipicephalus bursa and causative agents of EP. Most of the positive pools harbored a single infection (91.1%); mixed infections were also detected (8.9%). The infection rate for T. equi slightly decreased among years; B. caballi showed a lower, but increasing, infection rate. Tick phenology, climate variables, and peaks of EP prevalence indicated late May and second half of June as periods with the highest risk of new infections, especially during warm and dry days.  相似文献   
5.
Pectins are a major dietary nutrient source for the human gut microbiota. The prominent gut microbe Bacteroides thetaiotaomicron was recently shown to encode the founding member (BT1017) of a new family of pectin methylesterases essential for the metabolism of the complex pectin rhamnogalacturonan-II (RG-II). However, biochemical and structural knowledge of this family is lacking. Here, we showed that BT1017 is critical for the metabolism of an RG-II–derived oligosaccharide ΔBT1017oligoB generated by a BT1017 deletion mutant (ΔBT1017) during growth on carbohydrate extract from apple juice. Structural analyses of ΔBT1017oligoB using a combination of enzymatic, mass spectrometric, and NMR approaches revealed that it is a bimethylated nonaoligosaccharide (GlcA-β1,4-(2-O-Me-Xyl-α1,3)-Fuc-α1,4-(GalA-β1,3)-Rha-α1,3-Api-β1,2-(Araf-α1,3)-(GalA-α1,4)-GalA) containing components of the RG-II backbone and its side chains. We showed that the catalytic module of BT1017 adopts an α/β-hydrolase fold, consisting of a central twisted 10-stranded β-sheet sandwiched by several α-helices. This constitutes a new fold for pectin methylesterases, which are predominantly right-handed β-helical proteins. Bioinformatic analyses revealed that the family is dominated by sequences from prominent genera of the human gut microbiota, including Bacteroides and Prevotella. Our re-sults not only highlight the critical role played by this family of enzymes in pectin metabolism but also provide new insights into the molecular basis of the adaptation of B. thetaiotaomicron to the human gut.  相似文献   
6.
International Journal of Primatology - Information on parasite biodiversity and abundance can improve our understanding of parasitic infections on endangered wildlife, as parasites can affect host...  相似文献   
7.
The aims of the present study were to investigate the anticonvulsant activity and behavioral toxicity of FrPbAII using freely moving Wistar rats. Moreover, the effectiveness of this compound against chemical convulsants was compared to that of the inhibitor of the GABAergic uptake, nipecotic acid. Our results show that FrPbAII was effective against seizures induced by the i.c.v. injection of pilocarpine (ED(50) = 0.05 microg/animal), picrotoxin (ED(50) = 0.02 microg/animal), kainic acid (ED(50) = 0.2 microg/animal) and the systemic administration of PTZ (ED(50) = 0.03 microg/animal). The anticonvulsant effect of FrPbAII differed from that of nipecotic acid in potency, as the doses needed to block the seizures were more than 10 folds lower. Toxicity assays revealed that in the rotarod, the toxic dose of the FrPbAII is 1.33 microg/animal, and the therapeutic indexes were calculated for each convulsant. Furthermore, the spontaneous locomotor activity of treated animals was not altered when compared to control animals but differed from the animals treated with nipecotic acid. Still, FrPbAII did not induce changes in any of the behavioral parameters analyzed. Finally, when tested for cognitive impairments in the Morris water maze, the i.c.v. injection of FrPbAII did not alter escape latencies of treated animals. These findings indicate that the novel GABA uptake inhibitor is a potent anticonvulsant with mild side-effects when administered to Wistar rats.  相似文献   
8.
A 10-year-old female cat was brought to Istituto Zooprofilattico Sperimentale delle Regioni Lazio e Toscana for post-mortem examination. The animal used to live, together with 26 other cats, in the big terrace of an apartment at the 8th floor in Rome; and was always fed with industrial pet food. Anamnesis referred balance troubles, vomit and convulsions, during a couple of days, followed by sudden death. At necropsy, the cat presented mucoid rhinitis, purulent tracheitis, small areas of pneumonia, dark spots in the liver, catarrhal-hemorrhagic gastritis, fibrinous enteritis and meningeal hyperemia. Thoracic and abdominal cavities were completely invaded by hundreds of larval stages of cestodes. The same parasites were also included in nodules in pancreatic, lung and kidney parenchyma. Microscopic examination of parasites allowed their identification as larval stages (metacestodes) of cestodes of the genus Mesocestoides. The molecular genotyping of the metacestodes indicates a close relationship with members of the genus Mesocestoides, although a significant variation was found with respect to the available sequences of other species of the genus.  相似文献   
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