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2.
Sci Rep ; 12(1): 1736, 2022 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-35110637

RESUMEN

In the USA, historical data on the period over which industrial swine farms have operated are usually only available at the county scale and released every 5 years via the USDA Census of Agriculture, leaving the history of the swine industry and its potential legacy effects on the environment poorly understood. We developed a changepoint-based workflow that recreates the construction timelines of swine farms, specifically by identifying the construction years of swine manure lagoons from historical Landsat 5 imagery for the period of 1984 to 2012. The study focused on the Coastal Plain of North Carolina, a major pork-producing state in the USA. The algorithm successfully predicted the year of swine waste lagoon construction (+ /- 1 year) with an accuracy of approximately 94% when applied to the study area. By estimating the year of construction of 3405 swine waste lagoons in NC, we increased the resolution of available information on the expansion of swine production from the county scale to spatially-explicit locations. We further analyzed how the locations of swine waste lagoons changed in proximity to water resources over time, and found a significant increase in swine waste lagoon distances to the nearest water feature across the period of record.


Asunto(s)
Crianza de Animales Domésticos/historia , Granjas/historia , Industria de Alimentos/historia , Carne de Cerdo , Sus scrofa , Animales , Monitoreo del Ambiente/historia , Historia del Siglo XX , Historia del Siglo XXI , North Carolina , Aguas del Alcantarillado , Factores de Tiempo , Eliminación de Residuos Líquidos/historia
3.
Microb Ecol ; 68(3): 427-40, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24760169

RESUMEN

Florida Bay exhibits a natural gradient of strong P limitation in the east which shifts to weak P or even N limitation at the western boundary. This nutrient gradient greatly affects seagrass abundance and productivity across the bay. We assessed the effects of N and P additions on sediment bacterial community structure in relation to the existing nutrient gradient in Florida Bay. Sediment samples from 24 permanent 0.25 m(2) plots in each of six sites across Florida Bay were fertilized with granular N and P in a factorial design for 26 months. Sediment bacterial community structure was analyzed using PCR-denaturing gradient gel electrophoresis (DGGE) analysis of 16S ribosomal RNA (rRNA) genes and a cloning strategy from DGGE bands. The phylogenetic positions of 16S rRNA sequences mostly fell into common members found in marine sediments such as sulfate-reducing Deltaproteobacteria, Gammaproteobacteria, Spirochaetes, and Bacteriodetes. Twenty-eight common DGGE bands were found in all sediment samples; however, some DGGE bands were only found or were better represented in eastern sites. Bacterial community diversity (Shannon-Weiner index) showed similar values throughout all sediment samples. The N treatment had no effect on the bacterial community structures across the bay. Conversely, the addition of P significantly influenced the bacterial community structure at all but the most western site, where P is least limiting due to inputs from the Gulf of Mexico. P additions enhanced DGGE band sequences related to Cytophagales, Ectothiorhodospiraceae, and Desulfobulbaceae, suggesting a shift toward bacterial communities with increased capability to degrade polymeric organic matter. In addition, a band related to Deferribacteres was enhanced in eastern sites. Thus, indigenous environmental conditions were the primary determining factors controlling the bacterial communities, while the addition of P was a secondary determining factor. This P-induced change in community composition tended to be proportional to the amount of P limitation obviated by the nutrient additions.


Asunto(s)
Bacterias/clasificación , Estuarios , Sedimentos Geológicos/microbiología , Nitrógeno/química , Fósforo/química , Filogenia , Bacterias/genética , ADN Bacteriano/genética , Electroforesis en Gel de Gradiente Desnaturalizante , Fertilizantes , Florida , ARN Ribosómico 16S/genética , Agua de Mar/química , Agua de Mar/microbiología , Análisis de Secuencia de ADN , Microbiología del Agua
4.
Exp Clin Transplant ; 11(5): 458-63, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23534438

RESUMEN

Metastatic melanoma is a donor-derived malignancy that has rarely been reported in liver allograft recipients. We present a case of a transmitted donor-derived melanoma to a liver allograft recipient in whom the diagnosis was established by polymerase chain reaction-based DNA fingerprinting. A 52-year-old African-American man underwent a successful orthotropic liver transplant for alcohol-induced cirrhosis. One year after the orthotropic liver transplant, he presented at our institution with diffuse abdominal pain, and a computed tomography scan of the abdomen and chest showed innumerable masses diffusely involving the liver and multiple subcutaneous nodules in the abdominal and chest wall. A liver biopsy confirmed the diagnosis of metastatic melanoma. The origin of melanoma was traced to the donor by DNA fingerprinting of the native liver, the donor liver, and the donor gallbladder. Chemotherapy was initiated with temozolomide (75 mg/m² daily) and thalidomide (50 mg daily), to which he responded within 8 weeks with radiologic improvement in metastatic lesions. Tacrolimus was switched to sirolimus because of renal insufficiency as well as reported effectiveness against melanoma. Our patient survived for 9 months after the diagnosis of metastatic melanoma. He ultimately died of brain metastases. Donor-derived metastatic melanoma is a rare cancer with the highest transmission and mortality rates, which requires better recognition. Prompt diagnosis of donor-derived melanoma is critical and can be achieved reliably with polymerase chain reaction-based DNA analysis. Management options after diagnosis include de-escalation of immunosuppression, with or without urgent organ removal or retransplant. The roles of chemotherapy, immunotherapy, and radiotherapy require further study.


Asunto(s)
Biomarcadores de Tumor/genética , Dermatoglifia del ADN , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundario , Trasplante de Hígado/efectos adversos , Melanoma/genética , Melanoma/secundario , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Donantes de Tejidos , Biopsia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundario , Progresión de la Enfermedad , Resultado Fatal , Humanos , Inmunosupresores/uso terapéutico , Neoplasias Hepáticas/terapia , Masculino , Melanoma/terapia , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Factores de Tiempo , Tomografía Computarizada por Rayos X
5.
Exp Clin Transplant ; 11(2): 154-63, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23480344

RESUMEN

OBJECTIVES: Organ donation after cardiac death remains an available resource to meet the demand for transplant. However, concern persists that outcomes associated with donation after cardiac death liver allografts are not equivalent to those obtained with organ donation after brain death. The aim of this matched case control study was to determine if outcomes of liver transplants with donation after cardiac death donors is equivalent to outcomes with donation after brain death donors by controlling for careful donor and recipient selection, surgical technique, and preservation solution. MATERIALS AND METHODS: A retrospective, matched case control study of adult liver transplant recipients at the University of Tennessee/Methodist University Hospital Transplant Institute, Memphis, Tennessee was performed. Thirty-eight donation after cardiac death recipients were matched 1:2, with 76 donation after brain death recipients by recipient age, recipient laboratory Model for End Stage Liver Disease score, and donor age to form the 2 groups. A comprehensive approach that controlled for careful donor and recipient matching, surgical technique, and preservation solution was used to minimize warm ischemia time, cold ischemia time, and ischemia-reperfusion injury. RESULTS: Patient and graft survival rates were similar in both groups at 1 and 3 years (P = .444 and P = .295). There was no statistically significant difference in primary nonfunction, vascular complications, or biliary complications. In particular, there was no statistically significant difference in ischemic-type diffuse intrahepatic strictures (P = .107). CONCLUSIONS: These findings provide further evidence that excellent patient and graft survival rates expected with liver transplants using organ donation after brain death donors can be achieved with organ donation after cardiac death donors without statistically higher rates of morbidity or mortality when a comprehensive approach that controls for careful donor and recipient matching, surgical technique, and preservation solution is used.


Asunto(s)
Trasplante de Hígado/mortalidad , Soluciones Preservantes de Órganos , Selección de Paciente , Donantes de Tejidos/estadística & datos numéricos , Obtención de Tejidos y Órganos/estadística & datos numéricos , Centros Médicos Académicos/estadística & datos numéricos , Adolescente , Adulto , Muerte Encefálica , Muerte , Femenino , Prueba de Histocompatibilidad , Humanos , Masculino , Persona de Mediana Edad , Morbilidad , Estudios Retrospectivos , Factores de Riesgo , Análisis de Supervivencia , Tennessee/epidemiología , Adulto Joven
6.
Liver Transpl ; 17(9): 1027-34, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21594966

RESUMEN

Hepatic sarcoidosis is a rare indication for liver transplantation. Using the United Network for Organ Sharing (UNOS)/Organ Procurement and Transplantation Network (OPTN) database, we evaluated patient and graft survival after orthotopic liver transplantation for sarcoidosis between October 1987 and December 2007. We assessed the potential prognostic value of multiple demographic and clinical variables, and we also compared these patients to a case-matched group of patients with primary sclerosing cholangitis (PSC) or primary biliary cirrhosis (PBC). The 1- and 5-year survival rates for the sarcoidosis group were 78% and 61%, respectively, and these rates were significantly worse than the rates for the PSC/PBC group (P = 0.001). Disease recurrence in the liver is a rare cause of graft loss or patient death. Three deaths occurred in the sarcoidosis group because of recurrent hepatic sarcoidosis, and 1 death was a result of cardiac sarcoidosis. A univariate analysis identified an increasing donor risk index as a significant negative factor for outcomes for the sarcoidosis group [hazard ratio (HR) = 2.06, confidence interval (CI) = 1.04-4.06, P = 0.037], but this finding was not found in a multivariate analysis, in which no independent predictors were found to have a significant impact. A case-matched univariate analysis demonstrated that sarcoidosis and morbid obesity were significant negative factors for outcomes, and in a multivariate analysis, sarcoidosis continued to predict worse outcomes (HR = 2.39, CI = 1.21-4.73, P = 0.012). In conclusion, an analysis of the UNOS/OPTN database indicates that the patient and allograft survival rates for hepatic sarcoidosis are satisfactory, but they are worse in comparison with the rates for other cholestatic liver diseases.


Asunto(s)
Colestasis Intrahepática/terapia , Trasplante de Hígado/métodos , Obtención de Tejidos y Órganos/métodos , Adulto , Colestasis Intrahepática/mortalidad , Estudios de Cohortes , Femenino , Humanos , Inflamación , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Modelos de Riesgos Proporcionales , Recurrencia , Sarcoidosis/mortalidad , Sarcoidosis/terapia , Resultado del Tratamiento
7.
Microb Ecol ; 59(2): 284-95, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19705193

RESUMEN

Community structure of sediment bacteria in the Everglades freshwater marsh, fringing mangrove forest, and Florida Bay seagrass meadows were described based on polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) patterns of 16S rRNA gene fragments and by sequencing analysis of DGGE bands. The DGGE patterns were correlated with the environmental variables by means of canonical correspondence analysis. There was no significant trend in the Shannon-Weiner index among the sediment samples along the salinity gradient. However, cluster analysis based on DGGE patterns revealed that the bacterial community structure differed according to sites. Not only were these salinity/vegetation regions distinct but the sediment bacteria communities were consistently different along the gradient from freshwater marsh, mangrove forest, eastern-central Florida Bay, and western Florida Bay. Actinobacteria- and Bacteroidetes/Chlorobi-like DNA sequences were amplified throughout all sampling sites. More Chloroflexi and members of candidate division WS3 were found in freshwater marsh and mangrove forest sites than in seagrass sites. The appearance of candidate division OP8-like DNA sequences in mangrove sites distinguished these communities from those of freshwater marsh. The seagrass sites were characterized by reduced presence of bands belonging to Chloroflexi with increased presence of those bands related to Cyanobacteria, gamma-Proteobacteria, Spirochetes, and Planctomycetes. This included the sulfate-reducing bacteria, which are prevalent in marine environments. Clearly, bacterial communities in the sediment were different along the gradient, which can be explained mainly by the differences in salinity and total phosphorus.


Asunto(s)
Bacterias/genética , Sedimentos Geológicos/microbiología , Microbiología del Agua , Humedales , Bacterias/clasificación , Biodiversidad , Análisis por Conglomerados , ADN Bacteriano/genética , Electroforesis en Gel de Poliacrilamida , Florida , Agua Dulce/microbiología , Fósforo/análisis , Filogenia , Poaceae/microbiología , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Rhizophoraceae/microbiología , Salinidad , Alineación de Secuencia , Análisis de Secuencia de ADN
8.
Rev Neurol Dis ; 6(1): 13-20, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19367219

RESUMEN

Fetal alcohol syndrome (FAS) is a leading cause of preventable birth defects and developmental disability with numerous neurologic and ophthalmic manifestations. FAS is identified by the presence of a characteristic facies, growth deficiency, and central nervous system abnormalities. A wide variety of ocular and neuro-ophthalmic conditions occur in FAS and result in lifelong visual impairment. Neurologists are frequently called upon to evaluate and recommend treatment for children with developmental delay or neurologic manifestations of FAS. We review the neuro-ophthalmic literature on FAS to alert neurologists to the ocular disease seen in patients with this condition. Timely ophthalmic referral and early intervention for treatable ophthalmic conditions, such as refractive errors, strabismus, and amblyopia, can prevent irreparable harm to the developing visual system and improve the overall neurologic development, long-term functioning, and quality of life for these patients.


Asunto(s)
Trastornos del Espectro Alcohólico Fetal/fisiopatología , Enfermedades del Sistema Nervioso/etiología , Enfermedades del Nervio Óptico/etiología , Estrabismo/etiología , Femenino , Trastornos del Espectro Alcohólico Fetal/diagnóstico , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Embarazo
9.
Hepatobiliary Pancreat Dis Int ; 7(6): 581-9, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19073402

RESUMEN

BACKGROUND: Ciliated foregut cysts of the liver are rare, with only 96 cases diagnosed since the first description in 1857. They are being increasingly diagnosed recently; the majority of the cases have been reported in the last 15 years. Although they bear a close resemblance to the simple cyst of the liver which has essentially a benign course, ciliated hepatic foregut cysts (CHFCs) can progress to malignancy with devastating consequences. It is imperative that this group of conditions be diagnosed and treated adequately. DATA SOURCES: This review includes discussion of the data from all the 96 reported cases from English and non-English literature. Analysis of the incidence rates, embryogenesis, growth, clinical features, risk of malignancy and the prognosis are highlighted systematically. The roles of various diagnostic modalities including ultrasound, CT, MRI, fine needle aspiration cytology (FNAC), immunohistochemistry and surgery are further discussed. RESULTS: The mean age of patients with CHFC was 48+/-12 years. The male/female ratio was 1.1:1. The majority of patients with CHFC (62%) were asymptomatic, and the common mode of presentation was right upper abdominal pain. The cysts occurred in the left lobe in 51 patients, with sole location in segment IV in 44, and in the right lobe in 26. The average size of the cysts was 3.6+/-2.12 cm. The majority of the cysts were unilocular, and only 7 cases were multilocular. Cyst contents were described as viscous or mucinous in 73 patients, whereas bilious fluid was noted in 3. Large cysts having squamous carcinoma were cited in 3 patients, and 2 had extensive squamous metaplasia without malignancy. Others had benign histopathology. CONCLUSIONS: Clinicians have become increasingly aware of CHFC. Imaging alone is not diagnostic per se, but when considered in the context of the global picture does provide important clues to the diagnosis. FNAC is diagnostic by the presence of the ciliated columnar aspirate but lacks sensitivity. Infantile presentation is usually accompanied by biliary communication and mandates a different surgical approach. The demonstration of malignant transformation in 3 cases and its fatal course emphasizes the need for surgical resection in all cases once the diagnosis is made.


Asunto(s)
Cilios/patología , Quistes/epidemiología , Quistes/patología , Hepatopatías/epidemiología , Hepatopatías/patología , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/patología , Humanos , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/patología , Factores de Riesgo
10.
Ky Nurse ; 53(1): 12, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15748006

RESUMEN

Narayanasamy's (2002) study supported spiritual coping mechanisms as an important part of coping and recovery in chronically ill patients. The results of this study can be used to support a research utilization project to teach nurses the importance of supporting and promoting patient spirituality as a component of nursing care. A feasibility issue would include the need for spiritual assessment tools. Future research could focus on the importance of spirituality in patients of different age groups.

11.
J Bacteriol ; 186(1): 80-9, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14679227

RESUMEN

Bacterial spore heat resistance is primarily dependent upon dehydration of the spore cytoplasm, a state that is maintained by the spore peptidoglycan wall, the spore cortex. A peptidoglycan structural modification found uniquely in spores is the formation of muramic delta-lactam. Production of muramic delta-lactam in Bacillus subtilis requires removal of a peptide side chain from the N-acetylmuramic acid residue by a cwlD-encoded muramoyl-L-Alanine amidase. Expression of cwlD takes place in both the mother cell and forespore compartments of sporulating cells, though expression is expected to be required only in the mother cell, from which cortex synthesis derives. Expression of cwlD in the forespore is in a bicistronic message with the upstream gene ybaK. We show that ybaK plays no apparent role in spore peptidoglycan synthesis and that expression of cwlD in the forespore plays no significant role in spore peptidoglycan formation. Peptide cleavage by CwlD is apparently followed by deacetylation of muramic acid and lactam ring formation. The product of pdaA (yfjS), which encodes a putative deacetylase, has recently been shown to also be required for muramic delta-lactam formation. Expression of CwlD in Escherichia coli results in muramoyl L-Alanine amidase activity but no muramic delta-lactam formation. Expression of PdaA alone in E. coli had no effect on E. coli peptidoglycan structure, whereas expression of CwlD and PdaA together resulted in the formation of muramic delta-lactam. CwlD and PdaA are necessary and sufficient for muramic delta-lactam production, and no other B. subtilis gene product is required. PdaA probably carries out both deacetylation and lactam ring formation and requires the product of CwlD activity as a substrate.


Asunto(s)
Bacillus subtilis/fisiología , Lactamas/metabolismo , Ácidos Murámicos/metabolismo , Peptidoglicano/química , Amidohidrolasas/genética , Amidohidrolasas/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Lactamas/química , Ácidos Murámicos/química , N-Acetil Muramoil-L-Alanina Amidasa/genética , N-Acetil Muramoil-L-Alanina Amidasa/metabolismo , Operón , Peptidoglicano/metabolismo , Esporas Bacterianas/metabolismo
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