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1.
Mol Ecol ; 32(12): 3200-3219, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36943181

RESUMO

Little is known about when and how planktonic species arise and persist in the open ocean without apparent dispersal barriers. Pteropods are planktonic snails with thin shells susceptible to dissolution that are used as bio-indicators of ocean acidification. However, distinct evolutionary units respond to acidification differently, and defining species boundaries is therefore crucial for predicting the impact of changing ocean conditions. In this global population genomic study of the shelled pteropod Limacina bulimoides, we combined genetic (759,000 single nucleotide polymorphisms) and morphometric data from 161 individuals, revealing three major genetic lineages (FST = 0.29-0.41): an "Atlantic lineage" sampled across the Atlantic, an "Indo-Pacific lineage" sampled in the North Pacific and Indian Ocean, and a "Pacific lineage" sampled in the North and South Pacific. A time-calibrated phylogeny suggests that the lineages diverged about 1 million years ago, with estimated effective population size remaining high (~10 million) throughout Pleistocene glacial cycles. We do not observe any signatures of recent hybridization, even in areas of sympatry in the North Pacific. While the lineages are reproductively isolated, they are morphologically cryptic, with overlapping shell shape and shell colour distributions. Despite showing that the circumglobal L. bulimoides consists of multiple species with smaller ranges than initially thought, we found that these pteropods still possess high levels of genetic variability. Our study adds to the growing evidence that speciation is often overlooked in the open ocean, and suggests the presence of distinct biological species within many other currently defined circumglobal planktonic species.


Assuntos
DNA Mitocondrial , Plâncton , Humanos , Animais , Filogeografia , Plâncton/genética , Concentração de Íons de Hidrogênio , DNA Mitocondrial/genética , Água do Mar , Filogenia , Caramujos/genética
2.
Clin Oral Investig ; 25(3): 933-945, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32556663

RESUMO

OBJECTIVES: In reconstructive surgery, flap monitoring is crucial for early identification of perfusion problems. Using hyperspectral imaging (HSI), this clinical study aimed to develop a non-invasive, objective approach for perfusion monitoring of free and pedicled flaps. MATERIAL AND METHODS: HSI of 22 free (FF) and 8 pedicled flaps (PF) in 30 patients was recorded over time. Parameters assessed were tissue oxygenation/superficial perfusion (0-1 mm) (StO2 (0-100%)), near-infrared perfusion/deep perfusion (0-4 mm) (NIR (0-100)), distribution of haemoglobin (THI (0-100)), and water (TWI (0-100)). Measurements up to 72 h were correlated to clinical assessment. RESULTS: Directly after flap inset, mean StO2 was significantly higher in FF (70.3 ± 13.6%) compared with PF 56.2 ± 14.2% (p = 0.05), whereas NIR, THI, and TWI were similar (NIR_p = 0.82, THI_p = 0.97, TWI_p = 0.27). After 24 h, StO2, NIR, THI, and TWI did not differ between FF and PF. After 48 h, StO2, NIR, and TWI did not differ between FF and PF whereas THI was significantly increased in FF compared with PF(p = 0.001). In three FF, perfusion decreased clinically and in HSI, 36(1), 40(2), 5(3), and 61(3) h after flap inset which was followed by prompt intervention. CONCLUSIONS: StO2 < 40%, NIR < 25/100, and THI < 40/100 indicated arterial occlusion, whereas venous problems revealed an increase of THI. In comparison with FF, perfusion parameters of PF were decreased after flap transfer but remained similar to FF later on. CLINICAL RELEVANCE: HSI provides objective and non-invasive perfusion monitoring after flap transplantation in accordance to the clinical situation. With HSI, signs of deterioration can be detected hours before clinical diagnosis.


Assuntos
Imageamento Hiperespectral , Procedimentos de Cirurgia Plástica , Estudos de Viabilidade , Humanos , Perfusão , Retalhos Cirúrgicos
3.
Clin Oral Investig ; 21(3): 771-778, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27170294

RESUMO

OBJECTIVES: Recent studies focused on angiogenesis in the pathophysiology of bisphosphonate-associated osteonecrosis of the jaws (BP-ONJ) and identified geranylgeraniol (GGOH) as a feasible option for BP-ONJ therapy. This study investigated the influence of GGOH on microvessel sprouting after BP-incubation in vitro. MATERIALS AND METHODS: Ten experimental set-ups were randomly designed in an in vitro 3D-angiogenesis assay. Two groups included HUVEC cell spheroids with and without (±) GGOH substitution as controls and eight groups pairwise contained either clodronate or the nitrogen-containing bisphosphonates (N-BP) ibandronate, pamidronate, and zoledronate ± GGOH. The size of the cell spheroids including the outbranching sprouts (SpS) as well as the density (SpD) and length of the sprouts (SpL) were analyzed by a grid system after 0, 24, 48, and 72 h. RESULTS: For controls and NN-BP clodronate, no significant differences at any tested parameter and any point of measurement could be detected within the experimental set-ups ± GGOH (p each ≥0.05). For N-BP ibandronate, the experimental set-ups +GGOH showed a significantly increased SpS, SpD, and SpL after 48 and 72 h (p each ≤0.002) compared to the experimental set-ups -GGOH. For N-BPs pamidronate and zoledronate, the experimental set-ups + GGOH demonstrated a significantly increased SpS, SpD, and SpL after 24, 48, and 72 h (p each ≤0.001) compared to the experimental set-ups -GGOH. CONCLUSIONS: The strong negative influence of N-BPs on microvessel sprouting could be significantly reversed by GGOH. CLINICAL RELEVANCE: Since supportive therapeutic options for BP-ONJ are lacking, GGOH might be a promising substitute for BP-ONJ prevention and therapy.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/tratamento farmacológico , Conservadores da Densidade Óssea/efeitos adversos , Conservadores da Densidade Óssea/farmacologia , Difosfonatos/efeitos adversos , Difosfonatos/farmacologia , Diterpenos/farmacologia , Microvasos/efeitos dos fármacos , Neovascularização Patológica/tratamento farmacológico , Células Endoteliais da Veia Umbilical Humana , Humanos , Técnicas In Vitro
4.
Br J Oral Maxillofac Surg ; 60(5): 623-628, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35317937

RESUMO

Fibular free flap (FFF) is the main reconstructive choice for large mandibular defects. Recent improvements have been made regarding planning and surgical procedure, but choice of osteosynthesis material (OSM) for segment-fixation remains controversial. A retrospective cohort study obtained clinical and radiological data from FFF-patients. Data were screened for OSM, surgical procedure and complications as OSM fractures, loosening, exposure, or insufficient osseous consolidation. Eighty patients with FFF were included. Planning was CAD/CAM (n=29), Recon Guide (n=26) or without planning (n=25). OSM was 2.0mm-miniplates in standard (n=26), preformed (n=6), CAD/CAM (n=14) or ReconGuide (n=23) variation and 2.3mm-reconstruction-plates in standard (n=5) or CAD/CAM (n=6) variation. Complications were observed in 21 cases, fractures occurred 10 times overall, but with low rates for preformed (n=1), ReconGuide (n=3) and none for CAD/CAM. Analysis detected significant correlations between used OSM and plate exposure (p = 0.000), but none regarding fracture (p = 0.275), loosening (p = 0.714) or insufficient osseous consolidation (p = 0.208). No correlations were observed between complications and OSM (p = 0.609) or diagnosis (p = 0.716). Fixation of FFF segments for reconstruction is possible with various OSM providing good clinical outcome. No significant differences were detected regarding prevention of complications by any osteosynthesis material (miniplate vs. macroplate). Although no differences were detected, miniplate usage is advocated whenever clinically reasonable, due to easier reintervention possibilities and reduced implanted foreign material. Nevertheless, decision for ideal OSM must remain patient-specific and cannot be generalised.


Assuntos
Retalhos de Tecido Biológico , Reconstrução Mandibular , Placas Ósseas , Fíbula/cirurgia , Humanos , Reconstrução Mandibular/métodos , Estudos Retrospectivos
5.
Chirurg ; 91(3): 216-221, 2020 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-31965197

RESUMO

BACKGROUND: When using digitalization and artificial intelligence (AI), large amounts of data (big data) are produced, which can be processed by computers and used in the field of microvascular-reconstructive craniomaxillofacial surgery (CMFS). OBJECTIVE: The aim of this article is to summarize current applications of digitalized medicine and AI in microvascular reconstructive CMFS. MATERIAL AND METHODS: Review of frequent applications of digital medicine for microvascular CMFS reconstruction, focusing on digital planning, navigation, robotics and potential applications with AI. RESULTS: The broadest utilization of medical digitalization is in the virtual planning of microvascular transplants, individualized implants and template-guided reconstruction. Navigation is commonly used for ablative tumor surgery but less frequently in reconstructions. Robotics are mainly employed in the transoral approach for tumor surgery of the hypopharynx, whereas the use of AI is still limited even if possible applications would be automated virtual planning and monitoring systems. CONCLUSION: The use of digitalized methods and AI are adjuncts to microvascular reconstruction. Automatization approaches and simplification of technologies will provide such applications to a broader clientele in the future; however, in CMFS, robotic-assisted resections and automated flap monitoring are not yet the standard of care.


Assuntos
Procedimentos de Cirurgia Plástica , Robótica , Inteligência Artificial , Previsões , Retalhos Cirúrgicos
6.
Sci Rep ; 7(1): 12645, 2017 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-28974691

RESUMO

Pteropods are among the first responders to ocean acidification and warming, but have not yet been widely explored as carriers of marine paleoenvironmental signals. In order to characterize the stable isotopic composition of aragonitic pteropod shells and their variation in response to climate change parameters, such as seawater temperature, pteropod shells (Heliconoides inflatus) were collected along a latitudinal transect in the Atlantic Ocean (31° N to 38° S). Comparison of shell oxygen isotopic composition to depth changes in the calculated aragonite equilibrium oxygen isotope values implies shallow calcification depths for H. inflatus (75 m). This species is therefore a good potential proxy carrier for past variations in surface ocean properties. Furthermore, we identified pteropod shells to be excellent recorders of climate change, as carbonate ion concentration and temperature in the upper water column have dominant influences on pteropod shell carbon and oxygen isotopic composition. These results, in combination with a broad distribution and high abundance, make the pteropod species studied here, H. inflatus, a promising new proxy carrier in paleoceanography.


Assuntos
Ácidos/isolamento & purificação , Aquecimento Global , Oceanos e Mares , Água do Mar/análise , Ácidos/química , Animais , Oceano Atlântico , Mudança Climática , Gastrópodes/química , Humanos , Paleontologia , Propriedades de Superfície , Temperatura
7.
J Maxillofac Oral Surg ; 14(Suppl 1): 469-74, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25861199

RESUMO

PURPOSE: Plasmocytoma of the bone represents a variance of plasma cell neoplasms, which often gives hint for systemic affection. A case of a mandibular tumor as first manifestation of multiple myeloma (MM) is presented and discussed with the literature. MATERIALS AND METHODS: A 76-year old female with pain and swelling of the right lower jaw was assigned to the hospital. Radiograph showed a lytic tumor at the mandibular condyle and histological analysis gave evidence of a plasma cell tumor with positivity to CD138. In further examinations, elevated immunoglobulin levels in serum and osseous plasma cell infiltration unveiled MM. PubMed-database was searched by "multiple myeloma primary lesion jaw", "multiple myeloma primary manifestation mandible" and "multiple myeloma mandibular lesion" within the last 30 years. RESULTS: Together with the current case, 11 reports including 13 patients were found describing mandibular plasmocytoma as first sign for MM. Mean age was 59 years with slight female preference. Initial symptoms were mostly swelling episodes with or without pain. The main radiological presentation was a uni- or multilocular radiolucency. After a mean follow up time of 29 months (stated in 8 cases; standard deviation 50, min: 1, max: 151), 3/8 patients died and in 5/8 cases, signs of progress were seen. CONCLUSION: In rare cases, occurrence of plasmocytoma of the mandible is first sign for MM and should always lead to further investigations regarding systemic disease. Simple examinations such as panoramic X-rays can lead to early detection of MM and thereby better prognosis by earlier treatment.

8.
Clin Chim Acta ; 76(2): 187-91, 1977 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-193656

RESUMO

The concentration and composition of the lipoprotein density classes d less than 1.006 (VLDL), d = 1.006 - 1.064 (LDL), and d = 1.064 - 1.21 (HDL) of human umbilical cord serum were investigated by means of preparative ultracentrifugation. The concentrations of all the density classes, in particular that of the VLDL, are lower than in adults; the values correspond to 8.1 (VLDL), 59.2 (LDL), and 77.4 (HDL) mg/100 ml. About 15% of the total cholesterol and roughly 40% of the total lipid phosphorus did not float at the highest density of 1.21. The composition of the LDL and the HDL was principally in agreement with the pattern obtained in adults. The VLDL of the cord serum, however, showed a lower amount of triglycerides (45%) and a higher content of proteins (22%) than the VLDL from serum of adults. In cord serum only 25% of the total triglycerides are associated with the VLDL fraction, while more than 50% of the triglycerides circulate as a constituent of the LDL.


Assuntos
Sangue Fetal/análise , Lipoproteínas/sangue , Colesterol/sangue , Ésteres do Colesterol/sangue , Feminino , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Lipoproteínas VLDL/sangue , Fosfolipídeos/sangue , Gravidez , Triglicerídeos/sangue , Ultracentrifugação
10.
Beitr Pathol ; 154(2): 170-81, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-1122225

RESUMO

The fine structure and pinocytic activity of the rat visceral yolk sac epithelium were examined electron microscopically after incubation in Krebs-Ringer-Phosphate solution containing either 125-I-labeled albumin or goat antirat-placenta-IgG or both compounds simultaneously. Addition of 125-I-albumin to the incubation medium stimulates the pinocytosis, whereas the addition of goat antirat-placenta-IgG, cross-reacting with the yolk sac tissue, causes a diminution of the pinocytic activity of the yolk sac epithelium. Fine structural alterations and lesions are generally noticed. Preincubation of yolk sacs in Krebs-Ringer-Phosphate solution containing goat antirat-placent-IgG and the subsequent postincubation in a new Krebs-Ringer-Phosphate medium with 125-I-albumin does not restore the original pinocytic activity of the visceral epithelial cells.


Assuntos
Imunoglobulina G/análise , Pinocitose , Membrana Vitelina/imunologia , Animais , Membrana Celular , Meios de Cultura , Epitélio , Feminino , Cabras/imunologia , Soros Imunes , Lisossomos , Fagócitos , Placenta/imunologia , Ratos , Soroalbumina Radioiodada , Membrana Vitelina/citologia , Membrana Vitelina/ultraestrutura
11.
Beitr Pathol ; 159(1): 33-50, 1976 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-999598

RESUMO

The susceptibility of rat fetal membranes (visceral yolk sac) to cell-mediated immunity was studied electron microscopically at day 19 of pregnancy. For this purpose guinea-pigs were sensitized to rat placental antigens and the activated lymphocytes were injected intrauterinely. Simultaneously, the effect of lymphocytes from non-sensitized guinea-pigs was examined on the rat yolk sac. Lymphocytes from sensitized guinea-pigs revealed a clear cytotoxic effect on the visceral yolk sac, but the degree of cell destruction showed marked differences from one epithelial cell to the other. Furthermore, the yolk sac regionally displayed great differences in the intensity of immune cytolysis...


Assuntos
Linfócitos/imunologia , Prenhez , Membrana Vitelina/imunologia , Animais , Testes Imunológicos de Citotoxicidade , Células Epiteliais , Membranas Extraembrionárias/imunologia , Feminino , Cobaias/imunologia , Microscopia Eletrônica , Gravidez , Ratos , Imunologia de Transplantes , Membrana Vitelina/ultraestrutura
12.
Acta Biol Med Ger ; 34(4): 613-23, 1975.
Artigo em Alemão | MEDLINE | ID: mdl-1237980

RESUMO

A tracer kinetic study with [14C]-1-palmitic acid was carried out to study the influence of acute exposure to cold and starvation on free fatty acid (FFA) metabolism in serum of newborn rabbits. The turnover rate of serum FFA was 10.20 mumol/min in well fed rabbits kept in a thermoneutral environment (normal conditions). Cold exposure as well as starvation either in a cold or thermoneutral environment resulted in a diminution of the turnover rate, being the consequence of a significantly reduced pool of FFA. It was 9.57 mumol under normal conditions. The disappearance rate (1.07 min-1), half time (0.65 min) and turnover time (0.94 min) of well nourished animals was slightly, but mostly not significantly, influenced by cold exposure and starvation. The cold induced increase in serum FFA concentration and the decrease following restoration of thermoneutrality did not run parallel with changes in the absolute turnover rate.


Assuntos
Temperatura Baixa , Ácidos Graxos não Esterificados/metabolismo , Fome , Animais , Animais Recém-Nascidos , Ácidos Graxos não Esterificados/sangue , Feminino , Fenômenos Fisiológicos da Nutrição , Gravidez , Coelhos
13.
Acta Physiol Acad Sci Hung ; 49(1): 1-16, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-755329

RESUMO

Pool size (M), and specific radioactivities (SA) of lipids of white adipose tissue (WAT), as well as the flow rates (ms) of free fatty acids (FFA) from plasma into WAT were studied by injecting 14C-1-palmitate (20.10(6) cpm/100 g body weight) into 7-day-old rabbits reared in a thermoneutral (Group I) or a cold environment (Group II) or subjected to starvation at an ambient temperature (Ta) of 35 degrees C (Group III) or at Ta 20 degrees C (Group IV). Experiments were carried out at Ta 20 degrees C in all four groups of rabbits. The pool size of esterified and non-esterified fatty acids of WAT was reduced in both the well-fed animals raised in the cold and in the starving ones. The SA of tissue FFA and phospholipid fatty acid (PL-FA) was highest in Group III and Group IV indicating an increased FFA metabolism of WAT in animals subjected to starvation prior to acute exposure to cold. The flow rate (ms) of FFA between plasma and WAT increased twofold in Group IV but remained about one fifth that of the ms between plasma and brown adipose tissue (BAT) indicating that the contribution of WAT to cold-induced calorigenesis of the whole animal must be regarded as of secondary importance.


Assuntos
Tecido Adiposo/metabolismo , Temperatura Baixa , Ácidos Graxos/metabolismo , Animais , Animais Recém-Nascidos , Peso Corporal , Radioisótopos de Carbono , Dieta , Exposição Ambiental , Ácidos Graxos não Esterificados/sangue , Ácidos Graxos não Esterificados/metabolismo , Cinética , Palmitatos/metabolismo , Fosfolipídeos/metabolismo , Coelhos , Inanição/metabolismo , Triglicerídeos/metabolismo
14.
Acta Biol Med Ger ; 36(2): 221-30, 1977.
Artigo em Alemão | MEDLINE | ID: mdl-906733

RESUMO

In rats receiving a fat-free food throughout the period of pregnancy, the individual fatty acids of total lipids from placenta, total fetus, maternal and fetal serum were determined quantitatively on day 21/22 of pregnancy. Also, the incorporation of 14C-acetate in vitro into placental fatty acids, divided by the number of double bonds, was measured and the rate of synthesis calculated therefrom. The fat-free diet caused a drastic fall of linoleic acid concentration in maternal serum and all fetal compartments. On the contrary, the amount of arachidonic acid remained almost unchanged in fetal serum and total fetus, and even slightly increased in placenta. In the maternal serum, too, the arachidonic acid concentration remained constant under fat-free diet. The observed concentration changes of single fatty acids in the maternal serum are reflected in all fetal compartments and led to a rise in total fatty acids in all sera and tissues studied. The height of rise decreased in the order: maternal serum less than placenta less than fetal serum less than total fetus. The rate of synthesis for arachidonic acid in placenta was on day 21/22 of pregnancy 0.3 (controls) and 0.5 (fat-free diet) micrometer/100 g placenta and hour, being able to cover the placenta's own need to less than one-third. The results suggest that the protection of the feto-placental unit against arachidonic acid deficiency under fat-free diet of the mother is provided mainly by a constant supply of maternal unit with arachidonic acid under normal conditions has to be ensured essentially by the mother.


Assuntos
Ácidos Araquidônicos/biossíntese , Gorduras na Dieta/metabolismo , Feto/metabolismo , Placenta/metabolismo , Animais , Ácidos Araquidônicos/metabolismo , Ácidos Graxos/metabolismo , Feminino , Metabolismo dos Lipídeos , Troca Materno-Fetal , Gravidez , Ratos
15.
Eur J Biochem ; 58(1): 15-22, 1975 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-1183431

RESUMO

Parameters of plasma free fatty acid metabolism (pool size, half time, disappearance rate, turnover time and absolute turnover rate), the influx of plasma free fatty acids into the glycerides of brown adipose tissue and the pathway of triglyceride synthesis in brown adipose tissue (glycerol-1-phosphate versus monoglyceride pathway) were examined after intravenous injection of [1-14C]palmitate in newborn rabbits. In the thermoneutral environment of 35 degrees C the turnover rate of plasma free fatty acids was 10.20 mumol/min per 100 g body weight and its flux into the glycerides of brown adipose tissue 0.367 mumol/min per 100 g body weight. Cold exposure at an ambient temperature of 20 degrees C caused a decrease to 5.84 mumol/min and 0.207 mumol/min per 100 g body weight, respectively. Both under basal conditions at an ambient temperature of 35 degrees C and under cold-induced thermogenesis at an ambient temperature of 20 degrees C triglyceride synthesis in brown adipose tissue ran through the glycerol 1-phosphate pathway.


Assuntos
Tecido Adiposo Marrom/metabolismo , Regulação da Temperatura Corporal , Temperatura Baixa , Ácidos Graxos não Esterificados/sangue , Triglicerídeos/biossíntese , Animais , Animais Recém-Nascidos , Diglicerídeos/metabolismo , Glicerídeos/metabolismo , Coelhos , Análise de Regressão
16.
Acta Biol Med Ger ; 34(8): 1311-20, 1975.
Artigo em Alemão | MEDLINE | ID: mdl-1210994

RESUMO

The flow rate of serum free fatty acids (FFA) into the lipids of brown adipose tissue (BAT) of newborn rabbits was determined by intravenous injection of [14C]-1-palmitate. For a normal 7 day old animal during acute cold exposure the flow rate is (1 hour in 20 degrees C ambient temperature) 0.209 mumol/minute, that is 3.6% of the serum FFA turnover. Prolonged cold exposure only induced an increase in FFA influx if the lipid depot had been depleted (48 hours starvation in 20 degrees C). Consequently, the BAT takes up serum FFA for heat production only after mobilisation of its lipid stores. It is supposed that the mechanism of the uptake of serum FFA by the BAT is connected with their esterification to triglycerides. The phospholipids of BAT which are not only membrane bound lipids are characterized by a high metabolism.


Assuntos
Tecido Adiposo Marrom/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Metabolismo dos Lipídeos , Animais , Sítios de Ligação , Ácidos Graxos não Esterificados/sangue , Mobilização Lipídica , Fosfolipídeos/metabolismo , Coelhos
17.
Biol Neonate ; 27(3-4): 221-31, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-1182243

RESUMO

Preincubation of rat visceral yolk sac with goat anti-rat placenta IgG and following incubation with 125I-HSA resulted in a reduction of the uptake of albumin by 30-50% in comparison with the controls. Inhibitors of respiration or glycolysis impair the ingestion of protein, likewise the reduction of the incubation temperature.


Assuntos
Imunoglobulina G , Placenta/imunologia , Albumina Sérica/metabolismo , Membrana Vitelina/metabolismo , Animais , Células Epiteliais , Epitélio/ultraestrutura , Feminino , Idade Gestacional , Cabras/imunologia , Gravidez , Ratos , Temperatura , Fatores de Tempo , Membrana Vitelina/ultraestrutura
18.
Biol Neonate ; 35(3-4): 209-12, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-435597

RESUMO

The syntheses of arachidonic acid and total fatty acids were measured in human placentas at the end of the first trimester and at term using 14C-acetate in in vitro incorporation experiments. The rates of arachidonic acid synthesis were determined to be 0.70 (first trimester) and 0.64 (term) mumol/h/100 g of placental tissue. The calculated rates of total fatty acid synthesis amount to 0.5 (first trimester) and 0.6 (term) mumol palmitate-equivalents/h/100 g. The results suggest that the human placenta seems to be not dependent on maternal arachidonic acid. Near term the placenta even could be source of arachidonic acid.


Assuntos
Ácidos Araquidônicos/biossíntese , Placenta/metabolismo , Ácidos Graxos/biossíntese , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Terceiro Trimestre da Gravidez
19.
Acta Biol Med Ger ; 38(4): 611-7, 1979.
Artigo em Alemão | MEDLINE | ID: mdl-525138

RESUMO

Pregnant Wistar rats were fed a fatfree diet from day 16--22 of pregnancy. On day 22, the fatty acid components of cholesterol esters, triglycerides, free fatty acids and phospholipids of maternal (brain, muscle, serum, white adipose tissue, liver) and fetal (brain, carcass, serum, liver) tissues, including the placenta, were examined gaschromatographically for the participation of linoleic and arachidonic acid. In all fetal and maternal organs the linoleic acid levels in the fatty acid patterns were strongly reduced. The alterations nearly always involved all the lipid fractions of a tissue and were mostly equal within a tissue. The strongest decreases of linoleic acid occurred in the placenta, and the weakest, in the lipids of maternal muscle and maternal adipose tissue. The linoleic acid alterations were principally similar in fetal and the corresponding maternal tissues, while being less pronounced in case of maternal muscle. The participation of arachidonic acid in the fatty acid pattern is completely retained in the lipids of fetal organs, and is even enhanced in those of the placenta.


Assuntos
Ácidos Araquidônicos/análise , Gorduras na Dieta , Ácidos Linoleicos/análise , Metabolismo dos Lipídeos , Placenta/metabolismo , Prenhez , Animais , Ésteres do Colesterol/análise , Ácidos Graxos não Esterificados/análise , Feminino , Feto/metabolismo , Troca Materno-Fetal , Fosfolipídeos/análise , Gravidez , Ratos , Distribuição Tecidual , Triglicerídeos/análise
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