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1.
Placenta ; 32(1): 79-85, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21115196

RESUMO

Copper is an essential trace element necessary for normal growth and development. During pregnancy, copper is transported from the maternal circulation to the fetus by mechanisms which have not been clearly elucidated. Two copper transporting ATPases, Menkes (ATP7A; MNK) and Wilson (ATP7B; WND) are known to be expressed in the placenta and are thought to have a role in copper transport to the fetus. In this study, the intracellular localisation of the MNK and WND proteins in the third trimester human placental tissue was investigated in detail using double-label immunohistochemistry and immuno-electron microscopy. MNK and WND were differentially localised within the placenta. MNK was present at the basal side of the syncytiotrophoblast layer and also within the fetal vascular endothelial cells, whereas WND was localised at the microvillous membrane of the syncytiotrophoblast. These data offer some insights into possible differential roles for MNK and WND within the placenta.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Placenta/metabolismo , Terceiro Trimestre da Gravidez/metabolismo , Adenosina Trifosfatases/fisiologia , Proteínas de Transporte de Cátions/fisiologia , ATPases Transportadoras de Cobre , Feminino , Imunofluorescência , Humanos , Imuno-Histoquímica , Gravidez , Transporte Proteico/fisiologia , Distribuição Tecidual , Trofoblastos/metabolismo
2.
Placenta ; 27(9-10): 968-77, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16356544

RESUMO

Copper is an essential trace element necessary for normal growth and development. During pregnancy, copper is transported from the maternal circulation to the fetus by mechanisms which have not been clearly elucidated. The copper uptake protein, hCTR1 is predicted to play a role in copper transport in human placental cells. This study has examined the expression and localisation of hCTR1 in human placental tissue and Jeg-3 cells. In term placental tissue the hCTR1 protein was detected as a 105 kDa protein, consistent with the size of a trimer which may represent the functional protein. A 95 kDa band, possibly representing the glycosylated protein, was also detected. hCTR1 was localised within the syncytiotrophoblast layer and the fetal vascular endothelial cells in the placental villi and interestingly was found to be localised toward the basal plasma membrane. It did not co-localise with either the Menkes or the Wilson copper transporting ATPases. Using the placental cell line Jeg-3, it was shown that the 35 kDa monomer was absent in the extracts of cells exposed to insulin, estrogen or progesterone and in cells treated with estrogen an additional 65 kDa band was detected which may correspond to a dimeric form of the protein. The 95 kDa band was not detected in the cultured cells. These results provide novel insights indicating that hormones have a role in the formation of the active hCTR1 protein. Furthermore, insulin altered the intracellular localisation of hCTR1, suggesting a previously undescribed role of this hormone in regulating copper uptake through the endocytic pathway.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Cobre/metabolismo , Placenta/metabolismo , Linhagem Celular Tumoral , Transportador de Cobre 1 , Estrogênios/fisiologia , Feminino , Homeostase/fisiologia , Humanos , Imuno-Histoquímica , Insulina/fisiologia , Gravidez , Progesterona/fisiologia
3.
Placenta ; 25(6): 512-7, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15135234

RESUMO

Copper is an essential trace element necessary for normal growth and development. During pregnancy, copper is transported from the maternal circulation to the fetus by mechanisms which have not been clearly elucidated. Two copper transporting ATPases, Menkes (ATP7A; MNK) and Wilson (ATP7B; WND) are known to be expressed in the placenta and are thought to have a role in copper transport to the fetus. In this study, the expression and localization of the MNK and WND proteins in the human placenta were investigated in detail using immunoperoxidase and double-label immunohistochemistry. MNK and WND are differentially localized within the placenta. MNK is present in the syncytiotrophoblast, the cytotrophoblast and the fetal vascular endothelial cells whereas WND is only in the syncytiotrophoblast. Placental levels of both proteins, measured by Western blot analysis, did not change across pregnancy. These data offer some insights into possible roles for MNK and WND within the placenta.


Assuntos
Adenosina Trifosfatases/análise , Proteínas de Transporte de Cátions/análise , Placenta/enzimologia , Proteínas Recombinantes de Fusão/análise , Western Blotting , ATPases Transportadoras de Cobre , Endotélio Vascular/enzimologia , Feminino , Feto/irrigação sanguínea , Idade Gestacional , Humanos , Técnicas Imunoenzimáticas , Imuno-Histoquímica , Gravidez , Trofoblastos/enzimologia
4.
Surg Gynecol Obstet ; 174(5): 369-75, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1570613

RESUMO

Surgical gowns must protect patients from the bacteria of operating room personnel and also protect staff members from the lethal viruses in the blood of patients. The current study was done to evaluate the barrier function of several surgical types of gowns during use in surgical procedures and identify the frequency of failure of the gowns and some causes for this failure. We performed direct observation of 234 operations during which the surgeon and the first assistant wore 535 gowns. Blood strikethrough occurred most often when contamination on the outside of the gown was heavy (20 per cent), but still occurred after medium (7 per cent) and small (1 per cent) contamination. We found significant differences between gowns based on the material used and the design of the gowns. Gowns reinforced with a second layer of material or a layer of plastic material were more effective at preventing strikethrough than a single layer of material. One gown was identified that was unacceptable for any use in the operating room. Gowns of different designs and degrees of protection should be chosen based on the body area likely to be exposed to blood and the amount of predicted blood contamination. Further improvement in gown materials and design are required, since surgeons cannot consider any of these gowns protective during strenuous use.


Assuntos
Roupa de Proteção , Procedimentos Cirúrgicos Operatórios , Sangue , Estudos de Avaliação como Assunto , Luvas Cirúrgicas , Plásticos , Segurança
5.
Ann Surg ; 214(5): 614-20, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1953115

RESUMO

The potential for transmission of deadly viral diseases to health care workers exists when contaminated blood is inoculated through injury or when blood comes in contact with nonintact skin. Operating room personnel are at particularly high risk for injury and blood contamination, but data on the specifics of which personnel are at greater risk and which practices change risk in this environment are almost nonexistent. To define these risk factors, experienced operating room nurses were employed solely to observe and record the injuries and blood contaminations that occurred during 234 operations involving 1763 personnel. Overall 118 of the operations (50%) resulted in at least one person becoming contaminated with blood. Cuts or needlestick injuries occurred in 15% of the operations. Several factors were found to significantly alter the risk of blood contamination or injury: surgical specialty, role of each person, duration of the procedure, amount of blood loss, number of needles used, and volume of irrigation fluid used. Risk calculations that use average values to include all personnel in the operating room or all operations performed substantially underestimate risk for surgeons and first assistants, who accounted for 81% of all body contamination and 65% of the injuries. The area of the body contaminated also changed with the surgical specialty. These data should help define more appropriate protection for individuals in the operating room and should allow refinements of practices and techniques to decrease injury.


Assuntos
Sangue , Cirurgia Geral , Doenças Profissionais/etiologia , Viroses/transmissão , Ferimentos Penetrantes/microbiologia , Traumatismos da Mão/microbiologia , Humanos , Medicina , Ferimentos Penetrantes Produzidos por Agulha/microbiologia , Fatores de Risco , Especialização
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