RESUMEN
Minimal incision breast reduction techniques resulting in periareolar scars are widely used. However, this technique is less suitable for patients with large areola diameters and relatively small breasts, requiring a modest reduction or lift only. As a result of the large nipple-areola complex larger amounts of skin must be removed in order to resect the complete peripheral areola, increasing the risk of high-riding nipples, breast flattening and incomplete areola resection resulting in a rest on the vertical scar. This report describes a modified technique offering a solution to these problems. In this technique intra-areolar incisions are used to reduce areola size without resecting large volumes of breast tissue and skin. Complete peripheral areolar resection is always possible and high-riding nipples are avoided.
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Mamoplastia/métodos , Pezones/patología , Femenino , Humanos , Adulto JovenRESUMEN
INTRODUCTION: Cold hypoxia is a common factor in cold tissue preservation and mammalian hibernation. The purpose of this study was to determine the effects of cold preservation on the function of the retractor (RET) muscle of the hamster in the non-hibernating state and compare these with previously published data (van der Heijden et al., 2000) on the rat cutaneus trunci (CT) muscle. MATERIALS AND METHODS: After cold storage (16 h at 4 degrees C), muscles were stimulated electrically to measure maximum tetanus tension (P(0)) and histologically analyzed. The protective effects of addition of the antioxidants trolox and deferiprone and the calcium release inhibitor BDM to the storage fluid were determined. RESULTS: After storage, the twitch threshold current was increased (from 60 to 500 microA) and P(0) was decreased to 27% of control. RET morphology remained unaffected. RET muscle function was protected by trolox and deferiprone (P(0), resp., 43% and 59% of control). Addition of BDM had no effect on the RET. CONCLUSIONS: The observed effects of cold preservation and of trolox and deferiprone on the RET were comparable to those on CT muscle function, as reported in a previously published study (van der Heijden et al., 2000). Both hamster RET and rat CT muscles show considerable functional damage due to actions of reactive oxygen species. In contrast to the CT, in the RET cold preservation-induced functional injury could not be prevented by BDM and was not accompanied by morphological damage such as necrosis and edema. This suggests that the RET myocytes possess a specific adaptation to withstand the Ca(2+) overload induced by cold ischemia.
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Frío , Contracción Muscular , Músculo Esquelético/fisiología , Preservación de Órganos , Animales , Cromanos/farmacología , Cricetinae , Deferiprona , Masculino , Mesocricetus , Contracción Muscular/efectos de los fármacos , Músculo Esquelético/anatomía & histología , Soluciones Preservantes de Órganos/farmacología , Piridonas/farmacología , RatasRESUMEN
OBJECTIVE: Vasodilation originating within the microcirculation ascends into proximal feed arteries during muscle contraction to attain peak levels of muscle blood flow. Ascending vasodilation (AVD) requires an intact endothelium, as does conducted vasodilation in response to acetylcholine (ACh). Whereas ischemia-reperfusion (I-R) can affect endothelial cell function, the effect of I-R on AVD is unknown. The authors tested the hypothesis that I-R (1h-1h) would impair AVD. METHODS: Using the retractor muscle of anesthetized hamsters, contractions were evoked using field stimulation (200 ms at 40 Hz every 2 s for 1 min) and ACh was delivered using microiontophoresis (1 microm tip, 500-4000 ms pulse at 800 nA). Feed artery responses were monitored 500-1500 microm upstream. RESULTS: Neither resting (51 +/- 4 microm) nor maximal diameter (81 +/- 5 microm; 10 microm sodium nitroprusside) following I-R (n = 8) were different from time-matched controls (n = 10). With peak active tension of 23 +/- 4 mN x mm(-2), control AVD was 26 +/- 2 microm. Following I-R, active tension fell by 48% (p < .05) and AVD by 57% (p < .05). Stimulation at 70 Hz restored active tension but AVD remained depressed by nearly half (p < .05), as did local and conducted responses to ACh. Nevertheless, control responses to 500 ms ACh were restored by increasing stimulus duration to 4000 ms. CONCLUSIONS: Ischemia-reperfusion impairs the initiation of feed artery dilation with muscle contraction and with ACh while conduction along the vessel wall is preserved. Respective components of endothelial cell signaling events may differ in their susceptibility to I-R.
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Músculo Esquelético/irrigación sanguínea , Daño por Reperfusión/fisiopatología , Vasodilatación , Acetilcolina/farmacología , Animales , Arterias/fisiopatología , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Cricetinae , Células Endoteliales/metabolismo , Endotelio/fisiopatología , Masculino , Mesocricetus , Músculo Esquelético/fisiopatología , Vasodilatadores/farmacologíaRESUMEN
The aim of this study was to investigate if the preservation of isolated skeletal muscles for 16 h at 4 degrees C could be improved by pre-storage perfusion (PSP). Two rat muscle models were used: the soleus (SOL) and a posterior strip of the cutaneous trunci (CT). The effects of a 10 min PSP (at 25 degrees C) with University of Wisconsin solution (UW) or HTK-Bretschneider solution (HTK) on muscle function were analysed. The perfusion model was validated by the demonstration that the SOL and CT could be perfused with donor blood, UW and HTK at a flow rate of 0.2 ml x min(-1) x g(-1) muscle for 10 min without any immediate adverse effects on muscle weight, function (maximum tetanus tension) and cytoarchitecture (multivariate analysis of variance, P >0.05; n =6). For each muscle type and for each solution, six perfused and six non-perfused muscles were stored for 16 h at 4 degrees C. In the perfused groups, the storage and perfusion solution were matched. For both muscle types, the function (maximum tetanus tension), weight and cytoarchitecture of pre-storage perfused muscles was not preserved any better than that of non-perfused muscles, irrespective of the solution used (multivariate analysis of variance, P >0.05). We conclude that PSP for 10 min with UW and HTK does not improve the preservation of function of rat skeletal muscles during storage for 16 h at 4 degrees C.