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1.
Am Health Drug Benefits ; 14(4): 147-153, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35261719

RESUMEN

Background: The Americans with Disabilities Act (ADA) prohibits discrimination based on physical or mental disabilities and requires that employers provide reasonable accommodations to workers with disabilities who can perform their essential job functions. However, the ADA also states that an employer is not required to hire or keep an individual with a psychiatric disability if it poses a direct threat to his or her safety or the safety of others. Objectives: To identify employers' disclosure requirements for mental illness diagnosis or treatment during the job application process and/or as a condition of ongoing employment, to determine disclosure requirements of state and federal licensing bodies, and to evaluate the legality of disclosure of mental health status. Methods: We conducted an Internet-based search to identify public and private employers' disclosure requirements based on 4 keyword combinations, including "employment/mental health," "employment/mental illness," "license application/mental illness," and "license application/mental health." Other employers were included based on known federal and/or state certification requirements or a governing body policy for employee suitability and fitness. A panel of 3 investigators reviewed the data and analyzed the key findings, industry trends, and workplace implications. Results: Of the 23 industries (eg, construction, government, military, transportation) investigated, 5 were public and 18 were private. Public employees and government-regulated companies often required disclosure of mental health conditions because of the nature of the work. Private companies showed more variability than public in whether applications contained disclosure requirements, some of which were not compliant with the ADA regulations. Conclusion: Across the United States, job applicants and workers are often asked to disclose mental health status as a condition of employment. Consequently, applicants and workers may hide mental health issues, resulting in the underuse of mental health resources by those in need.

2.
Ann Plast Surg ; 70(2): 222-6, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22395053

RESUMEN

The efficacy of calcium channel blockers in reducing the effects of ischemia/reperfusion (I/R) injury in animals subjected to cigarette smoke was examined. In this study, 40 rats were divided into 4 groups. Groups A, B, and C received a controlled cigarette smoke exposure for 14 days, following which all animals underwent a standardized sciatic nerve I/R procedure. One sciatic nerve was isolated, and the femoral artery was occluded for 3 hours followed by reperfusion. Group B received verapamil (20 mg/kg/d). Group C received nifedipine (10 mg/kg/d). Mean sciatic function index (SFI) was significantly higher in nonsmoking than smoking animals, and the sciatic function index of group B (verapamil) and group C (nifedipine) was significantly greater than group A (smoking). Mean malondialdehyde at day 28 in group A was 0.96 ± 0.14 compared with 0.74 ± 0.11 in the nonsmoking group (P = 0.03), and the mean malondialdehyde in the nifedipine group was significantly greater than in group A (P = 0.05). Histologic injury scores were not significantly different among groups exposed to smoke. Smoking was associated with slower recovery following peripheral nerve I/R injury, but calcium channel blockers were shown to ameliorate these effects.


Asunto(s)
Bloqueadores de los Canales de Calcio/farmacología , Daño por Reperfusión/tratamiento farmacológico , Nervio Ciático/efectos de los fármacos , Fumar/efectos adversos , Vasodilatadores/farmacología , Animales , Cotinina/sangre , Modelos Animales de Enfermedad , Masculino , Nifedipino/farmacología , Ratas , Ratas Wistar , Daño por Reperfusión/sangre , Nervio Ciático/irrigación sanguínea , Verapamilo/farmacología
3.
Microsurgery ; 31(1): 59-65, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21207501

RESUMEN

This study was designed to determine if cigarette smoking adversely affects functional recovery following ischemia/reperfusion (I/R) injury in peripheral nerves. Forty Wistar rats were divided evenly among four groups. Animals in groups A and B were exposed to cigarette smoke via a controlled smoking chamber for 20 minutes daily. On study day 14, all animals underwent a controlled I/R injury to one sciatic nerve. Recovery was assessed with walking track assessments, malondialdehyde (MDA) assay, and histology. Walking track results on study day 21 did not differ significantly between the smoking and nonsmoking animals. However, by study day 28, the nonsmoking animals showed a greater degree of functional recovery (SFI = -18.0 and -22.8, respectively, P = 0.03). MDA concentration in the smoking group was significantly higher than the nonsmoking group at the 28 day time point (P = 0.04). Exposure to cigarette smoke was associated with a slower functional recovery following peripheral nerve I/R injury.


Asunto(s)
Nervios Periféricos/irrigación sanguínea , Daño por Reperfusión/fisiopatología , Fumar/fisiopatología , Animales , Cotinina/orina , Masculino , Malondialdehído/análisis , Estrés Oxidativo , Nervios Periféricos/patología , Ratas , Ratas Wistar , Recuperación de la Función , Daño por Reperfusión/patología , Nervio Ciático/fisiopatología
4.
Plast Reconstr Surg ; 125(3): 866-71, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20195113

RESUMEN

BACKGROUND: Calcium channel blockers have been shown experimentally to reverse many of the effects of nicotine. The purpose of this study was to assess the effect of calcium channel blockers on smoking-induced skin flap necrosis. METHODS: Forty male albino Wistar rats were divided into four groups. Groups A, B, and C were treated in a controlled smoking chamber for 20 minutes daily for 21 days. On day 14, caudally based dorsal skin flaps (3 x 10 cm) were created. On days 14 through 21, group B animals received verapamil (20 mg/kg/day) by gavage. Group C received nifedipine (10 mg/kg/day). On day 21, standardized photographs were taken and flap survival areas determined. Urine cotinine concentrations were measured on days 14 and 21. RESULTS: The mean cotinine level at surgery was 161 ng/ml in group A (smoking), 149 ng/ml in group B (verapamil), and 168 ng/ml in group C (nifedipine). These differences were not statistically significant. Cotinine concentration at surgery for group D (no smoking) was less than 10 ng/ml. The mean flap survival in group D was 79.1 percent, compared with 63.7 percent in group A (p = 0.003). The mean flap survival in group B (verapamil) was 72.8 percent, compared with 73.7 percent in group C (nifedipine). Both values were significantly greater than in group A (p = 0.04 and p = 0.008, respectively). CONCLUSIONS: In this study, enteral calcium channel blockers were associated with a statistically significant improvement in flap survival compared with untreated animals with an equivalent smoke exposure. Calcium channel blockers may reduce perioperative risk in active smokers who require skin flap surgery.


Asunto(s)
Bloqueadores de los Canales de Calcio/farmacología , Supervivencia de Injerto/efectos de los fármacos , Nifedipino/farmacología , Fumar/efectos adversos , Colgajos Quirúrgicos/patología , Verapamilo/farmacología , Animales , Bloqueadores de los Canales de Calcio/administración & dosificación , Cotinina/orina , Masculino , Necrosis/inducido químicamente , Nicotina/efectos adversos , Nicotina/antagonistas & inhibidores , Nifedipino/administración & dosificación , Ratas , Ratas Wistar , Fumar/patología , Colgajos Quirúrgicos/irrigación sanguínea , Vasodilatación/efectos de los fármacos , Verapamilo/administración & dosificación
5.
Hand (N Y) ; 3(1): 17-23, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18780115

RESUMEN

Composite tissue allotransplantation holds great promise for upper extremity reconstruction but is limited by donor part availability. Cryopreservation may increase the availability of donor parts and even reduce antigenicity. The purpose of the study was to evaluate the viability of cryopreserved composite tissues and to demonstrate the feasibility of microvascular isotransplantation of cryopreserved composite flaps. Twenty epigastric flaps were harvested from Lewis rats. Ten flaps were analyzed fresh. Ten flaps were perfused with dimethyl sulfoxide (DMSO)/trehelose cryoprotectant agent (CPA), frozen by controlled cooling to -140 degrees C, and stored for 2 weeks. Flaps were evaluated by factor VIII endothelial staining and MTT tetrazolium salt assay. For the in vivo phase, 30 flaps were harvested. Ten were transplanted fresh to isogenetic recipient animals, ten were perfused with CPA and transplanted, and ten were cryopreserved for 2 weeks, thawed, and transplanted. All cryopreserved samples displayed intact vascular endothelia on factor VIII staining. On MTT analysis, the epithelial viability index for the cryopreserved samples was not significantly different from fresh controls (p = 0.12). All freshly transplanted flaps (10/10) were viable at 60 days. Nine of ten flaps in the perfused/transplanted group were viable at 60 days. Survival of cryopreserved/transplanted flaps ranged from 5 to 60 days. The skin and vascular endothelial components of composite tissue flaps appear to retain their viability after cryopreservation. The in vivo studies demonstrate that the long-term survival of cryopreserved composite tissue transplants is feasible and support an indirect injury, rather than direct injury from freezing or cryoprotectant agents, as the mechanism of flap loss.

6.
Ann Plast Surg ; 60(5): 594-7, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18434838

RESUMEN

This study evaluates the viability of adipose aspirates harvested with the LipiVage system (Genesis Biosystems Inc, Lewisville, TX), a newly developed fat harvesting device, and determines a potentially preferred method for possible large-quantity fat graft harvesting. Adipose aspirates were harvested with the LipiVage system from the abdomen of 16 female patients (group 1, n = 8) according to the instruction by the manufacturer and with conventional liposuction (group 2, n = 8). Samples from conventional liposuction were spun at 50 g for 10 minutes and the resulting middle layer of fat was collected. All fat graft samples were evaluated with trypan blue vital staining for viable adipocyte count, glycerol-3-phosphatase dehydrogenase (G3PDH) assay for intracellular enzyme activity, and histology. In this study, group 1 had significantly higher viable adipocyte count than group 2 had (3.7 +/- 0.64 versus 2.37 +/- 0.56 x 10(6) /mL, P = 0.0021). G3PDH assay showed a marked increase of intracellular enzyme activity in group 1 compared with in group 2 (0.61 +/- 0.10 versus 0.34 +/- 0.13 U/mL, P = 0.00045). Histology revealed normal structures of fragmental fatty tissues in both groups. While adipose aspirates by both modalities maintain normal structure, the LipiVage system yields a greater number of viable adipocytes and sustains a higher level of intracellular enzyme activity within fat grafts and can potentially be a preferred method of choice for large-quantity fat graft harvesting.


Asunto(s)
Tejido Adiposo/trasplante , Supervivencia Tisular , Recolección de Tejidos y Órganos/instrumentación , Adulto , Femenino , Humanos , Persona de Mediana Edad , Trasplante Autólogo
7.
Cryobiology ; 55(3): 295-304, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17963742

RESUMEN

Despite advances in cryobiology, the reliable cryopreservation of complex tissues has not yet been achieved. This study evaluates the viability of cryopreserved composite flaps and demonstrates the feasibility of their transplantation. Epigastric flaps were harvested from male Lewis rats. 1.5M dimethyl sulfoxide (Me(2)SO) was used as the initial cryoprotectant agent (CPA). Samples were frozen at controlled rate to -140 degrees C and transferred to liquid nitrogen for at least two weeks. Hematoxylin and eosin (H/E) staining, MTT tetrazolium salt assay, and factor VIII immunostaining were used to evaluate the overall histology, epithelial viability, and vascular endothelial integrity, respectively, of cryopreserved flaps. For the in vivo phase, flaps were isotransplanted to 35 recipient animals, divided into three groups: fresh (n=10), perfused (n=8), and cryopreserved (n=17). Blood vessel patency was assessed via Doppler at 1, 7, and 60 days post-transplantation. For in vitro studies, cryopreserved samples (10/10) retained normal cell architecture and vascular endothelial integrity upon H/E and factor VIII staining. The viability index of cryopreserved composite flap skin (n=10) was 11.17+/-2.01, which was not significantly different from fresh controls (n=10, 12.15+/-1.32). All transplanted flaps in the fresh and perfusion groups survived with healthy color and hair growth at 60 days after operation. Survival in the cryopreserved group ranged from 2 to 60 days, with a mean of 12 days. These results demonstrate that the long term survival of cryopreserved composite tissue transplants is possible. Further studies are needed to refine protocols for the reliable cryopreservation of composite parts.


Asunto(s)
Criopreservación , Colgajos Quirúrgicos , Trasplante de Tejidos , Animales , Supervivencia Celular , Crioprotectores , Dimetilsulfóxido , Masculino , Ratas , Ratas Endogámicas Lew , Piel/citología , Conservación de Tejido
8.
Ann Plast Surg ; 58(6): 656-60, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17522490

RESUMEN

Cryopreservation has the potential to improve availability of donor parts for composite tissue allotransplantation and may reduce their antigenicity. This study investigates whether the component tissues of composite flaps remain viable after cryopreservation. Forty-one epigastric flaps were harvested from Lewis rats. Twenty-one flaps were perfused with DMSO/trehalose, frozen by controlled cooling to -140 degrees C, and stored in liquid nitrogen for 2 weeks. Ten fresh and 10 cryopreserved/thawed flaps were examined histologically with hematoxylin & eosin and factor VIII staining. An epithelial viability index was calculated for 10 fresh and 11 cryopreserved flaps using the MTT assay. In all cryopreserved samples, hematoxylin & eosin, and factor VIII staining revealed a well-preserved cellular architecture, which was indistinguishable from fresh specimens. The viability index for the cryopreserved samples was 10.90 +/- 2.09 compared with 12.15 +/- 1.32 for fresh flaps (P = 0.123). Results suggest that the skin, adipose, and vascular endothelial cells of composite tissue flaps retain their viability after cryopreservation and thawing.


Asunto(s)
Criopreservación/métodos , Colgajos Quirúrgicos , Animales , Supervivencia Celular , Criopreservación/instrumentación , Endotelio/metabolismo , Endotelio/trasplante , Diseño de Equipo , Indicadores y Reactivos , Masculino , Ratas , Ratas Endogámicas Lew , Sales de Tetrazolio/farmacocinética , Tiazoles/farmacocinética , Recolección de Tejidos y Órganos , Trasplante Homólogo
9.
Plast Reconstr Surg ; 117(6): 1845-50, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16651957

RESUMEN

BACKGROUND: The purpose of this study was to test the authors' hypothesis that previously cryopreserved adipose aspirates collected from conventional liposuction could still be a reliable source of human processed lipoaspirate cells. METHODS: Adipose aspirates were collected from 12 adult female patients after conventional liposuction of the abdomen and were then preserved by an optimal cryopreservation method with added cryoprotective agents (0.5 M dimethyl sulfoxide and 0.2 M trehalose). Cryopreservation of the adipose tissues was subsequently conducted with controlled slow cooling and then stored in liquid nitrogen (-196 degrees C). One gram of fresh or cryopreserved (after fast rewarming) adipose aspirates was processed in vitro and the resulting cell pellet, consisting of processed lipoaspirate cells, was cultured separately. The length of time until processed lipoaspirate cells became adherent to the culture plate was recorded and the number of processed lipoaspirate cells after a 2-week culture was counted. RESULTS: Flat, spindle-shape processed lipoaspirate cells from the cryopreserved group became adherent to the plate within 48 to 72 hours after initial culture compared with the fresh group, where the cells became adherent by 24 hours. After a 2-week culture, the cryopreserved aspirates yielded an average of 3.7 +/- 1.4 x 10(5) processed lipoaspirate cells per milliliter, equal to 90 percent of the yielded number of cells obtained from the fresh aspirates (4.1 +/- 1.4 x 10(5) cells/ml). CONCLUSIONS: The authors' results indicate that although there is a latency of cell growth after an optimal cryopreservation, cryopreserved adipose aspirates can yield a significant number of processed lipoaspirate cells compared with fresh aspirates and may be a reliable source of human processed lipoaspirate cells because they can still be processed later after long-term preservation.


Asunto(s)
Adipocitos/citología , Criopreservación/métodos , Lipectomía , Grasa Subcutánea Abdominal/citología , Recolección de Tejidos y Órganos/métodos , Adipocitos/efectos de los fármacos , Adulto , División Celular , Separación Celular/métodos , Forma de la Célula , Supervivencia Celular , Células Cultivadas/citología , Crioprotectores/farmacología , Dimetilsulfóxido/farmacología , Femenino , Humanos , Persona de Mediana Edad , Succión , Trehalosa/farmacología
10.
Aesthet Surg J ; 26(6): 653-61, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-19338955

RESUMEN

BACKGROUND: Successful long-term preservation of adipose tissues may have an important impact on future clinical application of autologous fat transplantation. Our group has recently developed an optimal cryopreservation method for possible long-term preservation of adipose aspirates. OBJECTIVE: The purpose of this study was to evaluate the fate of previously cryopreserved adipose aspirates after in vivo administration in an established nude mouse model. METHODS: Adipose aspirates were collected from a cosmetic lipoplasty of the patient's abdomen after centrifugation. In the fresh control group (n = 20), fresh adipose aspirates were injected into the posterior scalp of a nude mouse. In the optimal cryopreservation group (n = 20), adipose aspirates after the optimal cryopreservation were injected. In the simple cryopreservation group (n = 20), adipose aspirates after the simple cryopreservation were injected. All animals in each group were observed for gross appearance of maintained fat grafts over their posterior scalps for up to 16 weeks. The final volume and weight of maintained fat grafts and their histology were evaluated at the end of the study. RESULTS: More maintained volume, weight, and fatty tissue structure of injected free grafts were found in the optimal cryopreservation group compared with the simple cryopreservation group, but the results were still less satisfactory than those in the fresh control group. CONCLUSIONS: Based on this in vivo study, we believe that an optimal cryopreservation method developed in our laboratory provides reasonably good long-term preservation of adipose aspirates. However, further studies may still be warranted to refine our method for optimal cryopreservation of adipose tissues.

11.
Ann Plast Surg ; 54(3): 288-92; discussion 292, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15725835

RESUMEN

This study was conducted to evaluate the viability of fatty tissues within adipose aspirates after conventional liposuction and to examine their potential role as a source of donor material for possible future autogenous fat grafting. Samples of adipose aspirates (group I, n = 8) were obtained from adult female patients who underwent a conventional liposuction of the abdomen. Samples of fresh fatty tissues obtained from adult female patients who underwent an abdominoplasty (group II, n = 8) were cut into small pieces and served as a control. All samples were spun at 50 x g for 10 minutes; fatty tissues were then collected from the middle layer after centrifugation for the following studies: trypan blue vital staining for viable fatty cell counts, glycerol-3-phophatase dehydrogenase (G3PDH) assay for functional evaluation of fatty tissues, and routine pathology for histology of fatty tissues. There was no significant difference of viable fatty cell counts in group I compared with group II (2.57 +/- 0.56 versus 2.74 +/- 0.59 x 10/mL, P = 0.56). G3PGH assay showed a marked decrease of the enzyme activity in group I compared with group II (0.34 +/- 0.13 versus 0.76 +/- 0.13 micro/mL, P < 0.0001). Histologically, the normal structure of fatty tissues was found primarily in both groups. Our results indicate that although fatty tissues within adipose aspirates after conventional liposuction maintain normal structure with near the same number of viable fatty cells compared with fresh ones, they have a less-than-optimal level of cellular function and may not survive well after they are transplanted.


Asunto(s)
Tejido Adiposo/fisiología , Tejido Adiposo/trasplante , Lipectomía , Supervivencia Tisular/fisiología , Adipocitos/citología , Adipocitos/fisiología , Tejido Adiposo/citología , Recuento de Células , Femenino , Humanos , Recolección de Tejidos y Órganos
12.
Aesthet Surg J ; 25(2): 126-31, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-19338802

RESUMEN

BACKGROUND: Several studies have shown that one of the sugars, trehalose, can improve tissue survival after cryopreservation when combined with other cryoprotective agents, and thus may possibly be used in cryopreservation of adipose tissues that have been found more resistant to injury after freezing. OBJECTIVES: The purpose of this study was to test our hypothesis that lipoplasty-derived adipose aspirates could be effectively cryopreserved by adding trehalose as the sole cryoprotective agent (CPA), and to develop a practical technique to effectively preserve adipose tissues for future applications. METHODS: The middle layer of adipose aspirates obtained from conventional lipoplasty was collected after centrifugation and each specimen was randomized into 3 groups: the control group, fresh adipose aspirates without preservation; the simple cryopreservation group (no CPA); and the optimal cryopreservation group (with trehalose as a CPA). Cryopreservation of adipose aspirates was conducted with controlled slow cooling and fast rewarming rates. Fresh or cryopreserved adipose aspirates in each group were evaluated by viable adipocyte counts, glycerol-3-phosphate dehydrogenase (G3PDH) assay, and routine histology. RESULTS: More viable adipocytes and better cellular function of adipose aspirates were found in the optimal cryopreservation group compared to the simple cryopreservation group, but these results were less ideal than results from the control group. CONCLUSIONS: An optimal cryopreservation method using trehalose as a CPA appears to provide better long-term preservation of adipose aspirates than a simple cryopreservation method. Further studies are needed to refine our method for cryopreservation with trehalose as a CPA and confirm our findings in vivo.

13.
Aesthet Surg J ; 24(6): 536-41, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-19336206

RESUMEN

BACKGROUND: Optimal cryopreservation permits the long-term storage of living cells or tissues that may have potential clinical applications. Unfortunately, there are no successful studies on the long-term preservation of adipose aspirates for possible autologous fat grafting. OBJECTIVE: The purpose of the current study was (1) to test our hypothesis that adipose aspirates obtained from conventional lipoplasty could be preserved and stored at low temperature (below -85 degrees C) by means of an optimal cryopreservation technique and (2) to develop a novel approach to effectively preserve adipose aspirates for future applications. METHODS: The middle layer of adipose aspirates obtained from conventional lipoplasty was collected after centrifugation and each specimen was then randomized into 3 groups: the control group, fresh adipose aspirates without preservation; experimental group 1, simple cryopreservation with liquid nitrogen only; and experimental group 2, optimal cryopreservation with cryoprotective agents consisting of a combination of dimethyl sulfoxide (DMSO) and trehalose. Cryopreservation of adipose aspirates was conducted with controlled slow cooling and fast rewarming rates. Fresh or cryopreserved adipose aspirates in each group were evaluated by viable adipocyte counts, glycerol-3-phosphate dehydrogenase (G3PDH) assay, and routine histology. RESULTS: Significantly more viable adipocytes and better cellular function of adipose aspirates were found in the experimental group 2 compared to the results in the experimental group 1. CONCLUSIONS: Our results indicated that an optimal cryopreservation approach that utilizes a combination of DMSO and trehalose as cryoprotective agents appears to provide good long-term preservation of adipose aspirates obtained from conventional lipoplasty, albeit not as ideal as fresh specimens. An in vivo study will be conducted to confirm the results from our present in vitro study.

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