RESUMEN
BACKGROUND: The number of facelifts performed in the United States has steadily increased over the past decade. Moreover, the risk of venous thromboembolism in plastic surgery has been established in recent studies. OBJECTIVES: The authors investigate the overall complication rate in a single-center series to identify risk factors and determine the risk of venous thromboembolism. METHODS: A retrospective chart review was performed for patients who underwent a facelift procedure at a private clinic in Atlanta, Georgia, between January 2004 and December 2010. A total of 630 patients were included. The data collected included patient demographics, comorbidities, body mass index, smoking history, operative time, and concurrent procedures. All postoperative complications were recorded. RESULTS: The mean age of the patients in this series was 58.4±7.3 years. A small percentage of the patients were men (8.1%); 23.2% had hypertension; 4.9% were smokers; and 3.5% had a history of taking prophylactic aspirin. The mean operative time was 255.6±81.6 minutes. Almost a quarter (23.6%) of the patients underwent concurrent procedures. There were 38 complications, including 29 hematomas, two deep vein thromboses (DVTs), two eye infections, two instances of partial skin loss, and one ectropion. Risk of complications was significantly higher in men, patients over 55, and those with a body mass index>30 kg/m2. The risk of hematoma was higher (P<.05) in men, patients over 55, those with a history of hypertension, and those taking aspirin. The risk of DVT increased when the procedure time was longer than five hours. Both patients who developed DVT had undergone a facelift in combination with another procedure. There was also an increase in the risk of complications when the facelift was combined with two or more procedures. CONCLUSIONS: Identifying various risk factors for complications, especially DVT, can help to minimize those factors in the postoperative period and treat complications effectively when they occur. The data indicate that the number of concurrent procedures is a specific risk factor for development of DVT, so care should be taken when planning for multiple treatment sites. Combining facelift with other procedures also increases the risk of complications, especially DVT. LEVEL OF EVIDENCE: 4.
Asunto(s)
Complicaciones Posoperatorias/etiología , Ritidoplastia/efectos adversos , Tromboembolia Venosa/etiología , Abdomen/cirugía , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de RiesgoRESUMEN
The nuclear and magnetic structures of Mn3Fe2Si3 are investigated in the temperature range from 20 to 300â K. The magnetic properties of Mn3Fe2Si3 were measured on a single crystal. The compound undergoes a paramagnetic to antiferromagnetic transition at T N2 ≃ 120â K and an antiferromagnetic to antiferromagnetic transition at T N1 ≃ 69â K. A similar sequence of magnetic phase transitions is found for the parent compound Mn5Si3 upon temperature variation, but the field-driven transition observed in Mn5Si3 is not found in Mn3Fe2Si3, resulting in a strongly reduced magnetocaloric effect. Structurally, the hexagonal symmetry found for both compounds under ambient conditions is preserved in Mn3Fe2Si3 through both magnetic transitions, indicating that the crystal structure is only weakly affected by the magnetic phase transition, in contrast to Mn5Si3 where both transitions distort the nuclear structure. Both compounds feature a collinear high-temperature magnetic phase AF2 and transfer into a non-collinear phase AF1 at low temperature. While one of the distinct crystallographic sites remains disordered in the AF2 phase in the parent compound, the magnetic structure in the AF2 phase involves all magnetic atoms in Mn3Fe2Si3. These observations imply that the distinct sites occupied by the magnetic atoms play an important role in the magnetocaloric behaviour of the family.
Asunto(s)
Mamoplastia/métodos , Colgajos Quirúrgicos/irrigación sanguínea , Implantes de Mama , Neoplasias de la Mama/cirugía , Femenino , Estudios de Seguimiento , Rechazo de Injerto , Supervivencia de Injerto , Humanos , Mamoplastia/efectos adversos , Mastectomía/métodos , Microcirculación/fisiología , Medición de Riesgo , Factores de TiempoRESUMEN
The role of the sphingolipid ceramide in modulating the immune response has been controversial, in part because of conflicting data regarding its ability to regulate the transcription factor NF-kappaB. To help clarify this role, we investigated the effects of ceramide on IL-2, a central NF-kappaB target. We found that ceramide inhibited protein kinase C (PKC)-mediated activation of NF-kappaB. Ceramide was found to significantly reduce the kinase activity of PKCtheta as well as PKCalpha, the critical PKC isozymes involved in TCR-induced NF-kappaB activation. This was followed by strong inhibition of IL-2 production in both Jurkat T leukemia and primary T cells. Exogenous sphingomyelinase, which generates ceramide at the cell membrane, also inhibited IL-2 production. As expected, the repression of NF-kappaB activation by ceramide led to the reduction of transcription of the IL-2 gene in a dose-dependent manner. Inhibition of IL-2 production by ceramide was partially overcome when NF-kappaB nuclear translocation was reconstituted with activation of a PKC-independent pathway by TNF-alpha or when PKCtheta was overexpressed. Importantly, neither the conversion of ceramide to complex glycosphingolipids, which are known to have immunosuppressive effects, nor its hydrolysis to sphingosine, a known inhibitor of PKC, was necessary for its inhibitory activity. These results indicate that ceramide plays a negative regulatory role in the activation of NF-kappaB and its targets as a result of inhibition of PKC.