No description available.

Thesis (M.S.)--University of Massachusetts Amherst, 2008. / Includes bibliographical references (p. 58-62).

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Na produÃÃo in vitro (PIV) de embriÃes bovinos vÃrios fatores contribuem para as variÃveis na produÃÃo e qualidade dos oÃcitos e embriÃes. Avaliou-se o uso parenteral de vitamina A (VA) e vitamina E (VE) na produÃÃo de oÃcitos colhidos por aspiraÃÃo folicular (OPU) e embriÃes por produÃÃo in vitro (PIV) em de vacas (n=22), sendo: Simental (S) (n=2); Nelore (N) (n=4); Brahma (B) (n=5) e Gir (G) (n=11). Todos os animais foram alocados na fase prÃ-tratamento (F1) (n=22) (nÃo receberam vitaminas) e os mesmos animais utilizados para a fase pÃs-tratamento (F2) (receberam 1.000.000 UI de vitamina A e 1g de vitamina E). A primeira OPU foi na F1, logo em seguida foi aplicado 1.000.000 UI de VA e 1g de VE, e apÃs 12 dias realizou-se nova OPU para fazer a F2. Os oÃcitos (CCO) foram maturados, fecundados e cultivados in vitro. As 44 OPU produziram 520 oÃcitos, 217 (F1) e 303 (F2), havendo efeito significativo, com acrÃscimo de 86 oÃcitos, obtendo mÃdia e desvio padrÃo 9,86Â5,53 F1 e 13,77Â2,0 F2, (*p<0,0219). Quando separada as raÃas NBG (Nelore, Brahma e Gir) (n=20) houve acrÃscimo de 95 oÃcitos, obtendo mÃdia e desvio padrÃo 9,90Â5,81 F1-NBG e 14,65Â9,44 F2-NBG, (*p<0,0085). As 44 PIV produziram 224 embriÃes, sendo 93 F1 e 131 F2, obtendo mÃdia e desvio padrÃo 4,23Â3,09 F1 e 5,95Â4,05 F2, (*p<0,0228). Quando separada as NBG a produÃÃo foi de 214 embriÃes, havendo acrÃscimo de 38 embriÃes, obtendo valores de 4,45Â3,15 F1 e 6,25Â4,09 F2, (*p<0,0285). Houve um efeito significativo na quantidade produzida de oÃcitos (n=22) e oÃcitos NBG (n=20). Houve efeito na produÃÃo de embriÃes de todas as raÃas (n=22) e embriÃes NBG (n=20). A suplementaÃÃo com VA e VE aumentou o nÃmero de oÃcitos totais (1,7Â0,7); oÃcitos NBG (1,8Â0,8); embriÃes totais (3,9Â1,6) e embriÃes NBG (4,7Â1,6). A resposta da F2 comparado com a F1 na produÃÃo de oÃcitos e embriÃes foi significativa quando todas as raÃas estavam agrupadas e tambÃm quando foi agrupado apenas as Bos taurus indicus (NBG). O uso das vitaminas A e E pode ser usada para maior recuperaÃÃo oÃcitÃria e embrionÃria em raÃas ZebuÃnas. / The in vitro (IVP) bovine embryos production has several factors that contribute to the variables in the production and quality of oocytes and embryos. We evaluated the parenteral use of vitamin A (VA) and vitamin E (VE) in the production of oocytes collected by follicular aspiration (OPU) and embryos by in vitro production (IVP) in cows (n = 22), where: Simmental (S) (n = 2), Nelore (N) (n = 4), Brahma (B) (n = 5) and Gir (G) (n = 11). All animals were allocated in the pre-treatment (F1) (n = 22) (not receiving vitamins) and the same animals used for post-treatment (F2) (received 1,000,000 IU of vitamin A and vitamin 1g E). The first OPU was in F1, soon after 1,000,000 IU was administered 1 g of VE and VA, and after 12 days was held to make the new OPU F2. Oocytes (COC) were matured, fertilized and cultured in vitro. The OPU 44 yielded 520 oocytes, 217 (F1) and 303 (F2), with significant effect, an increase of 86 oocytes, obtaining mean and standard deviation 9.86 Â 5.53 13.77 Â 2.0 F1 and F2, (*p <0.0219). When separate races NBG (Nelore, Brahman and Gir) (n = 20) there was an increase of 95 oocytes, obtaining mean and standard deviation 9.90 Â 5.81 and 14.65 NBG F1-F2-NBG Â 9.44, (*p <0.0085). The 44 IVP embryos produced 224, 93 F1 and 131 F2, getting mean and standard deviation 4.23 Â 3.09 5.95 Â 4.05 F1 and F2, (*p <0.0228). When separated from the NBG production was 214 embryos, with an increase of 38 embryos, obtaining values of 4.45 Â 3.15 6.25 Â 4.09 F1 and F2, (*p <0.0285). There was a significant effect on the quantity produced of oocytes (n = 22) and NBG oocytes (n = 20). It was an increased in all breeds embryos production (n = 22) and NBG embryos (n = 20). Supplementation with VE and VA increased the total number of oocytes (1.7 Â 0.7); NBG oocytes (1.8 Â 0.8); total embryos (3.9 Â 1.6) and embryos NBG (4 7 Â 1.6). The response of the F2 compared to F1 in the production of oocytes and embryos was significant when all races were grouped together and also when it was grouped only Bos taurus indicus (NBG). The use of vitamins A and E can be used to greater oocyte recovery and embryo in Zebu breeds.

FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O objetivo do presente trabalho foi investigar a existÃncia de variaÃÃo sazonal nos conteÃdos de carotenÃides provitamina A (&#61537;&#61485; e &#61538;&#61485;caroteno) e vitamina E (&#61537;&#61485; e &#61540;&#61485;tocoferol) em duas espÃcies de macroalgas marinhas vermelhas, Cryptonemia luxurians e C. crenulata. As algas foram coletadas mensalmente de janeiro a dezembro de 2007, durante as marÃs baixas na Praia do Pacheco, Caucaia, CearÃ. Em laboratÃrio as algas foram desidratadas em estufa a 40ÂC por 15 horas. O material desidratado foi triturado atà a obtenÃÃo de um pà fino e, em seguida, submetido aos procedimentos de extraÃÃo com metanol, saponificaÃÃo com hidrÃxido de potÃssio e partiÃÃo em n-hexano. Para a anÃlise simultÃnea de carotenÃides e tocoferÃis, por cromatografia lÃquida de alta eficiÃncia, uma coluna Waters Spherisorb-Hichrom S5 ODS-2 (4,6 x 250 mm) e fase mÃvel de MeOH: THF (95:5, v/v), com fluxo de 1,5 mL min -1 foram utilizadas, com detecÃÃo em 450 nm e 292 nm, respectivamente. Em ambas as espÃcies pertencentes ao gÃnero Cryptonemia foram detectados &#61537;&#61485;&#61472;e &#61538;&#61485;caroteno ao longo dos meses de coleta. De uma maneira geral, as duas espÃcies apresentaram maiores teores de &#61538;&#61485;caroteno que &#61537;&#61485;caroteno. Apesar de as macroalgas analisadas pertencerem ao mesmo gÃnero, foi possÃvel verificar uma variaÃÃo nos teores de carotenÃides provitamina A ao longo do ano entre as espÃcies. C. luxurians pode ser eleita como melhor fonte de vitamina A que C. crenulata. Dentre os isÃmeros da vitamina E, &#61537;&#61485;tocoferol apresentou as maiores concentraÃÃes. C. luxurians exibiu os maiores teores de ambos os tocoferÃis. De acordo com os resultados obtidos no presente estudo, as macroalgas marinhas C. luxurians e C. crenulata desidratadas em estufa a 40ÂC por 15 horas possivelmente sÃo melhores fontes de vitamina E do que de vitamina A. Para avaliar o comportamento sazonal dos teores de &#61537;&#61485; e &#61538;&#61485;caroteno e &#61537;&#61485; e &#61540;&#61485;tocoferol, foi utilizada a anÃlise de agrupamentos. A partir dessa anÃlise constatou-se que os teores de tocoferÃis apresentaram variaÃÃo mais proeminente, tanto entre as estaÃÃes do ano como entre as espÃcies, quando comparados com os carotenÃides provitamina A, os quais demonstraram maior estabilidade nos teores por espÃcie e por estaÃÃo do ano. Entretanto, somente a partir de estudos posteriores serà possÃvel determinar quais fatores e sua influÃncia na variaÃÃo dos teores de carotenÃides provitamina A e vitamina E das espÃcies analisadas. / The objective of this research project was to investigate the existence of seasonal variation of both provitamin A carotenoids (&#61537;&#61485; and &#61538;&#61485;carotene) and vitamin E (&#61537;&#61485; and &#61540;&#61485;tocopherol) in two species of red marine macroalgae, Cryptonemia luxurians and C. crenulata. The alga samples were collected monthly from January to December of 2007, during the low tides of Pacheco Beach, Caucaia, CearÃ. The alga samples were dehydrated at 40ÂC for 15 h. The dried alga material was crushed into a fine powder and then submitted into the procedures of extraction with methanol, saponification with potassium hydroxide and partition with n-hexane. For simultaneous analyses of carotenoids and tocopherols the HPLC system consisted of a Waters Spherisorb-Hichrom S5 ODS-2 (4.6 x 250 mm) column and a mobile phase of MeOH: THF (95:5, v/v), delivered at 1.5 mL min -1 , with detection at 450 nm and 292 nm, respectively. In both species belonging to the genre Cryptonemia were detected &#61537;&#61485; and &#61538;&#61485;carotene throughout all the sampling months. In general, both species contained larger concentrations of &#61538;&#61485;carotene than &#61537;&#61485;carotene. Despite the macroalgae analyzed belonged to the same genre, it was possible to verify a variation in the concentrations of provitamin A carotenoids throughout the year. C. luxurians was elected as a better source of vitamin A than C. crenulata. Among the isomers of vitamin E, &#61537;&#61485;tocopherol showed the higher concentrations. C. luxurians showed the highest levels of both tocopherols. According to these results, C. luxurians and C. crenulata oven-dried at 40ÂC for 15 h are possibly better sources of vitamin E than vitamin A. To verify the seasonal behavior of the concentrations of provitamin A carotenoids and vitamin E, grouping analysis was utilized. Based upon the results of this analysis it was established that tocopherol concentrations showed a more substantiated variation in the macroalgae within the seasons of the year as well as among the two species. On the other hand, the provitamin A carotenoids, exhibited more stable concentrations considering the species and the seasons. Nevertheless, only with subsequent studies it will be possible to determine the factors and its influence on the variation of provitamin A carotenoids and vitamin E contents of the analyzed species.

No description available.

Die Phosphatase PDXP (auch bekannt als Chronophin) gehört zur Familie der HAD Phosphatasen, einer ubiquitär exprimierten Enzymklasse mit wichtigen physiologischen Funktionen. PDXP zeigt Phosphatase-Aktivität gegenüber seinem Substrat Pyridoxal 5´-Phosphat (PLP), der aktivierten Form von Vitamin B6. PDXP-defiziente Mäuse (Knockout-Mäuse) weisen im Vergleich zu Wildtypen verdoppelte PLP-Konzentrationen in Erythrozyten sowie im Gesamthirn auf. Vermutlich kommt PDXP daher eine wichtige Funktion in Erythrozyten und im Hirn zu. Ziel dieser Arbeit war es, erste Einblicke in diese Funktion(en) von PDXP zu erlangen. Hierzu wurden HPLC-basierte Analysen der erythrozytären PLP-Konzentrationen in Wildtyp- sowie PDXP-defizienten Mäusen durchgeführt. Dabei ließen sich die rund doppelt so hohen erythrozytären PLP-Level in den KO-Mäusen bestätigen. Zudem ist es gelungen, eine Methode zur Messung der endogenen Phosphatase-Aktivität von PDXP in Erythrozytenlysaten zu etablieren. So konnte im Wildtyp anhand der Verringerung der PLP-Konzentrationen pro Zeiteinheit eine erythrozytäre PDXP-Aktivität nachgewiesen werden. Dazu waren die Inkubation mit Pyridoxin, sowie die Anwendung eines Inhibitors der PDXK notwendig. Eine bis dato vermutete Funktion der PDXP, zur Mobilisation von erythrozytärem PLP während Fastenzeiten, konnte ausgeschlossen werden. So zeigte der Vergleich der erythrozytären PLP-Konzentrationen aus gefasteten mit normal gefütterten Tieren in beiden Genotypen exakt dieselbe prozentuale PLP-Verringerung. Während Nahrungszufuhr ließ sich jedoch eine Funktion der Phosphatase PDXP als „Converter“ von Pyridoxin zu Pyridoxal erkennen. Ausgehend von PN konnte im Wildtyp (über die Zwischenprodukte PNP und PLP) eine PDXP-abhängige Dephosphorylierung von PLP zu PL erfolgen. So wies der Wildtyp eine rund vierfach höhere PL-Produktion auf, verglichen mit der PDXP-defizienten Maus. Die Phosphatase PDXP erwies sich als essenziell für die erythrozytäre Konversion von Pyridoxin zu Pyridoxal. Dadurch erreicht der Organismus eine metabolische Flexibilität, die ihn bis zu einem gewissen Grad unabhängig von der Nahrungsauswahl macht. Zudem können Zellen oder Organe, denen durch das Fehlen der PNPO, die Konversion zu PLP nicht möglich ist, mit PL versorgt werden. Aus der hohen Reaktivität von PLP mit umliegenden Nucleophilen ergibt sich eine gewisse Problematik für die Zelle im Umgang mit freiem PLP. So liegt der Großteil des erythrozytären PLPs gebunden an Proteine (vor allem Hämoglobin) vor. Anhand von Filtern (MWCO, 3000) ließ sich zwischen der hier definiert als „freien“ und der „gebundenen“ Form von PLP differenzieren. So konnten erste Erkenntnisse zur Rolle von PDXP als Determinator freier PLP-Konzentrationen in Erythrozyten und insbesondere im Hippocampus erlangt werden. Im Hippocampus ergaben sich insgesamt deutlich höhere Konzentrationen an freiem PLP als in den Erythrozyten und es bestand zudem ein Unterschied zwischen den Genotypen. So wiesen die KO-Mäuse ~1/3 höhere freie PLP-Konzentrationen im Vergleich zu den Wildtypen auf. Schließlich konnte ein Effekt des Tieralters auf den PLP-Metabolismus festgestellt werden. Sowohl in den Erythrozyten als auch im Hippocampus ergaben sich alterskorrelierte Änderungen ihrer PLP-Konzentrationen. Zudem zeigten Western Blot Analysen altersbedingte Unterschiede ihrer Vitamin B6-Enzymexpressionen. So wiesen ältere Wildtypen im Hippocampus eine fünffach erhöhte PDXP-Expression verglichen mit jüngeren Tieren auf. In den Erythrozytenlysaten hingegen zeigten ältere Tiere beider Genotypen eine rund vierfach geringere PNPO-Expression gegenüber jüngeren Tieren. Die mit dem Alter eintretende physiologische Verringerung der erythrozytären PNPO-Expression würde somit für den Organismus einen Verlust seiner metabolischen Flexibilität bedeuten, die mit der Konversion von PN zu PL einhergeht. / The phosphatase PDXP, also called Chronophin, is a member of the ubiquitously expressed HAD-phosphatases, which have some important physiological functions in the organism. Its substrate pyridoxal 5´-phosphate (PLP) is the active form of vita-min B6, an important cofactor of several reactions. PDXP-deficient mice (KO-mice) have PLP-concentrations in erythrocytes and in the whole brain twice as high as wildtype mice. It is assumed that PDXP therefore has an important function in erythrocytes and in the brain. The aim of the study was to gain initial insights into these functions of PDXP. For this purpose, HPLC-based analyses of the PLP-concentrations in erythrocytes from WT- and KO-mice were carried out. The doubled PLP-levels in the RBCs of KO-mice could be confirmed. In addition, a method for measuring the endogenous phosphatase activity of PDXP in red cell lysates was established. The activity of PDXP could be measured by the reduction of its substrate PLP over time. This required the incubation with pyridoxine and the inhibition of PDXK by ginkgotoxine. An assumed function of PDXP in mobilization of PL(P) from the erythrocytes in fasting conditions could be ruled out. Therefore, a comparison between the PLP-concentrations in RBCs of fasted mice with normal fed ones was done. Surprisingly the fasted KO-mice showed the same percentaged decrease of cellular PLP-level as the fasted WT-mice. During vitamin B6 intake however, a function of PDXP as being a “converter” of pyridoxine to pyridoxal was found. Starting with PN, a PDXP-mediated dephosphorylation from PLP to PL could take place in the wildtype mice (via the intermediate steps PNP and PLP). Consequently, the WT´s production of PL quadrupled compared to the KO´s. PDXP turned out to be essential for the conversion of pyridoxine to pyridoxal in erythrocytes. This conversion confers some metabolic flexibility to the organism and to a certain extent makes it independent of the choice of food. Moreover, cells and organs, that due to the absence of PNPO cannot produce PL(P) themselves, can be provided via erythrocytes. The high reactivity of PLP with surrounding nucleophiles poses a certain problem for the cell in dealing with free PLP. The majority of the PLP in RBCs is bound to proteins (primarily hemoglobin). It was distinguished between the here termed “free” PLP and the bound PLP by using filter devices with a MWCO at 3 kDa. First insights could be gained about PDXP as a determinant of free PLP-levels in erythrocytes and hippocampus. The amount of free PLP in the hippocampus was significantly higher than in the RBCs. Additionally, the hippocampus showed some differences in the con¬centration of free PLP between WT- and KO-mice. The level of free PLP in PDXP deficient mice was one third higher than in wildtype mice. Finally, some correlation between the age of the mice and their PLP-metabolism was found. The results revealed changes of the PLP-concentrations with age in the RBCs and the hippocampus. Moreover, western blot analyses showed some age-related differences in the expression of vitamin B6 enzymes. In the hippocampus older wildtype mice showed a quintupled expression of PDXP compared to younger ones. However, western blot analyses of red blood cell lysates from older animals revealed a lower expression of PNPO by a factor of four. For the organism this physiological reduction of its PNPO expression with age would mean a loss of metabolic flexibility, that is accompanied by the conversion from PN to PL.

Vitamin D is a fat-soluble hormone essential for humans as it is a key player in calcium and phosphorus homeostasis for bone mineralization, and is linked to many nonskeletal health outcomes such as autoimmune diseases and cardiovascular disease as well. The primary source of vitamin D is the conversion of 7-dehydrocholestrol (7-DHC), which naturally exists in the plasma membranes of skin cells, to previtamin D3 by the exposure to the ultraviolet-B (UV-B) portion of sunlight. Despite humans’ ability to cutaneously synthesize vitamin D, many factors limit this process, and consequently vitamin D deficiency has become a common medical issue worldwide. Deficient individuals may not respond well to traditional vitamin D replacement through dietary supplementation if suffering from fat malabsorption syndromes while unable to get sufficient vitamin D from sun exposure due to location, sunscreen use, or cultural practices, among other reasons. It has been previously reported that exposure to artificial sources of UV-B radiation (UV lamps, tanning beds, among others) produces cutaneous vitamin D, but heat generation, poor portability, and other inconveniences to the deficient patient limit therapeutic use of these devices. In addition, broad-spectrum sources of UV radiation reduce the production of vitamin D compared to narrow-band sources because of the photoequilibrium that is established. The advent of the light-emitting diode (LED) provided a compact, energy-efficient, high-intensity, low-heat alternative radiation source, and the recent development of the UV LED offers a viable alternative for developing a personalized vitamin D-producing device. This thesis presents evidence that UV LEDs have the capacity to efficiently synthesize vitamin D3 in vitro and in human skin. Ampoules of 7-DHC were irradiated in triplicate with LEDs at 280, 285, 290, 295, 298, 300, and 310 nm. The 298 nm LED was found to have the most efficient previtamin D3 production of 7.0% in vitro at the equivalent of 0.75 minimal erythemal dose (MED, rated at 1 MED = 32 milliJoules per centimeter squared for type II skin), compared to all other assessed LEDs. Irradiation of human skin samples (IRB-exempt) with the 298 nm diode (~39 seconds of radiation) indicated that 1.5% of the original 7-DHC in type II (Caucasian) skin could be converted to vitamin D3 in situ after exposure to 0.75 MED. These results imply that manufacturing a cuff containing 298 nm LEDs that covers 3.8% of the total surface area of skin could provide 600 IUs of vitamin D3 if operated for just 39.0 seconds. The data provide a promising new approach to treat vitamin D-deficient patients suffering from fat malabsorption syndromes.

The maximum daily dose of vitamin D currently recommended is 2000 IU. Ergocalciferol (D2) 50,000 IU orally weekly for 8-12 weeks is often used to treat vitamin D deficient patients (25(OH) vitamin D <20 ng/mL). The lack of vitamin D toxicity after massive doses of ergocalciferol has yet to be reported in the literature. We report a case of a 56-year-old woman who received supratherapeutic doses of ergocalciferol (150,000 IU orally daily) for 28 years without toxicity. We discuss the possible mechanisms which may account for a lack of toxicity despite intake of massive daily doses of ergocalciferol in this patient.

No description available.

Thesis: M.S., Massachusetts Institute of Technology, Department of Nutrition and Food Science, 1980 / Includes bibliographical references. / by Thomas Henry Openshaw. / M.S. / M.S. Massachusetts Institute of Technology, Department of Nutrition and Food Science