Substrate utilization across the leg during 90 min of bicycle exercise at 58% of peak oxygen uptake (VO(2 peak)) was studied in seven endurance-trained males and seven endurance-trained, eumenorrheic females by applying arteriovenous catheterization, stable isotopes, and muscle biopsies. The female and male groups were matched according to VO(2 peak) per kilogram of lean body mass, physical activity level, and training history of the subjects. All subjects consumed the same diet, well controlled in terms of nutrient composition as well as energy content, for 8 days preceding the experiment, and all females were tested in the midfollicular phase of the menstrual cycle. During exercise, respiratory exchange ratio (RER) and leg respiratory quotient (RQ) were similar in females and males. Myocellular triacylglycerol (TG) degradation was negligible in males but amounted to 12.4 +/- 3.2 mmol/kg dry wt in females and corresponded to 25.0 +/- 6.0 and 5.0 +/- 7.3% of total oxygen uptake in females and males, respectively (P < 0.05). Utilization of plasma fatty acids (12.0 +/- 2.5 and 9.6 +/- 1.5%), blood glucose (13.6 +/- 1.5 and 14.3 +/- 1.5%), and glycogen (48.5 +/- 4.9 and 42.8 +/- 2.1%) were similar in females and males. Thus, in females, measured substrate oxidation accounted for 99% of the leg oxygen uptake, whereas in males 28% of leg oxygen uptake was unaccounted for in terms of measured oxidized lipid substrates. These findings may indicate that males utilized additional lipid sources, presumably very low density lipoprotein-TG or TG located between muscle fibers. On the basis of RER and leg RQ, it is concluded that no gender difference existed in the relative contribution from carbohydrate and lipids to the oxidative metabolism across the leg during submaximal exercise at the same relative workload. However, an effect of gender appears to occur in the utilization of the different lipid sources.
.-The resting content and use of myocellular triacylglycerol (MCTG) during 90 min of submaximal exercise [60% of peak oxygen uptake (V O2 peak)] were studied in 21 eumenorrheic female and 21 male subjects at different training levels [untrained (UT), moderately trained (MT), and endurance trained (END)]. Males and females were matched according to their V O2 peak expressed relative to lean body mass, physical activity level, and training history. All subjects ingested the same controlled diet for 8 days, and all females were tested in the midfollicular phase of the menstrual cycle. Resting MCTG, measured with the muscle biopsy technique, averaged 48.4 Ϯ 4.2, 48.5 Ϯ 8.4, and 52.2 Ϯ 5.8 mmol/kg dry wt in UT, MT, and END females, respectively, and 34.1 Ϯ 4.9, 31.6 Ϯ 3.3, and 38.4 Ϯ 3.0 mmol/kg dry wt in UT, MT, and END males, respectively (P Ͻ 0.001, females vs. males in all groups). Exercise decreased MCTG content in the female subjects by an average of 25%, regardless of training status, whereas in the male groups MCTG content was unaffected by exercise. The arterial plasma insulin concentration was higher (P Ͻ 0.05) and the arterial plasma epinephrine concentration was lower (P Ͻ 0.05) in the females than in the males at rest and during exercise. MCTG use was correlated to the resting concentration of MCTG (P Ͻ 0.001). We conclude that resting content and use of MCTG during exercise are related to gender and furthermore are independent of training status. muscle substrate; training; triglycerides IT HAS PREVIOUSLY BEEN SHOWN (25) that myocellular triacylglycerol (MCTG) is utilized during the postexercise period. MCTG stores also represent a potentially large energy source during exercise. However, the extent to which MCTG is used during exercise and the possible existence of differences in its use between trained and untrained (UT) subjects are still under debate. In studies (27, 37) using stable isotope techniques combined with indirect calorimetry, it was estimated that MCTG accounted for 20-25% of the oxidative metabolism during submaximal exercise. However, when direct measurements of MCTG concentration in muscle biopsies have been used, some studies (4, 19, 34) have found a decrease in MCTG concentration during submaximal exercise, whereas others (1, 21, 22, 25, 44) have observed no change. In all of the above-mentioned studies, only male subjects have participated. Thus it is unknown whether gender differences exist in the utilization of MCTG during exercise. Some studies (18,45,46) have shown that females utilize lipids to a greater extent than males during submaximal exercise, but to our knowledge it has not been investigated whether this increased lipid utilization in females is primarily from MCTG or other lipid sources. Other studies (3, 6, 32) have not been able to find gender differences in lipid utilization during exercise. This could be due to differences in training status and exercise mode in the experimental designs. The aim of the present study was therefore to evaluate the contribution of MCT...
Pregnancy in Cushing's syndrome (CS) is extremely rare due to the influence of hypercortisolism on the reproductive axis. Purpose of this study is to investigate whether the etiology of CS in pregnancy determines a different impact on the fetal/newborn and maternal outcomes. We performed a systematic review of cases published in the literature from January 1952 to April 2015 including the words "Cushing AND pregnancy". We included 168 manuscripts containing 220 patients and 263 pregnancies with active CS during pregnancy and with a history of CS but treated and cured hypercortisolism at the time of gestation. Adrenal adenoma was the main cause of active CS during pregnancy (44.1 %). Women with active CS had more gestational diabetes mellitus (36.9 vs. 2.3 %, p = 0.003), gestational hypertension (40.5 vs. 2.3 %, p < 0.001) and preeclampsia (26.3 vs. 2.3 %, p = 0.001) than those with cured disease. The proportion of fetal loss in active CS was higher than in cured CS (23.6 vs. 8.5 %, p = 0.021), as well as global fetal morbidity (33.3 vs. 4.9 %, p < 0.001). The predictors of fetal loss in active CS were etiology of hypercortisolism [Odds Ratio -OR-for pregnancy-induced CS 4.7 (95 % Confidence Interval-CI 1.16-18.96), p = 0.03], publication period [OR for "1975-1994" 0.10 (95 % CI 0.03-0.40), p = 0.001] and treatment during gestation (p = 0.037, [OR medical treatment 0.25 (95 % CI 0.06-1.02), p = 0.052], [OR surgical treatment 0.34 (95 % CI 0.11-1.06), p = 0.063]). The period of diagnosis of CS (before, during or after pregnancy) was the only predictor of overall fetal morbimortality [OR for diagnosis during pregnancy 4.66 (95 % CI 1.37-15.83), p = 0.014]. Patients with active CS, especially in pregnancy-induced CS, experienced more problems in pregnancy and had the worst fetal prognosis in comparison to other causes. Diagnosis of CS during pregnancy was also associated with worse overall fetal morbimortality. Both medical treatment and surgery during pregnancy appeared to be protective in avoiding fetal loss.
Overt Cushing’s syndrome is a rare disorder with an annual incidence of 2–3/million of which benign adrenal adenomas account for 0.6/million. The female:male ratio is 3:1. Preliminary data indicate a high proportion of subclinical Cushing’s syndrome in certain risk populations such as patients with type 2 diabetes or osteoporosis. The clinical implications of these observations are presently unclear. Surgery remains first line treatment for overt disease and initial cure or remission is obtained in 65–85% of patients with Cushing’s disease. Late recurrences, however, occur in up to 20% and the risk does not seem to plateau even after 20 years of follow-up. A 2- to 3-fold increase in mortality is observed in most studies, and this excess mortality seems confined to patients in whom initial cure was not obtained. Cushing’s syndrome continues to pose diagnostic and therapeutic challenges and life-long follow-up is mandatory.
Laccase (EC 1.10.3.2) is a multicopper enzyme belonging to the blue multicopper oxidase family. The most studied laccases are of fungal and plant origin [1][2][3][4][5], however, some bacterial laccases [6,7] have also been isolated. In addition, these enzymes have been found in some insects [8][9][10]. Laccases catalyze the oxidation of a wide range of organic and inorganic substances [11]. Typical organic substrates are aromatic compounds, such as different phenols, anilines and benzenethiols [11][12][13][14][15][16][17]. Laccases catalyze single-electron oxidation of the substrate, with concomitant reduction of molecular oxygen to water as shown in Scheme 1 [18]:Attempts to utilize the reactivity of laccase on phenolic substrates have been made, e.g., in pulp and paper, textile and food applications. Denim bleaching with a laccase-mediator system has been launched in the textile industry. The other applications, i.e., kraft pulp bleaching and detoxification have been only tested in laboratory or pilot scale [19]. Interest in the use of laccases in food processing is also increasing [20][21][22][23]. Laccases have been tested in bread making, where they can improve bread volume [24]. They can cross-link pentosans and arabinoxylans via ferulic acid (FA) side-chains [25,26]. It has been suggested that this kind of cross-linking of feroylated carbohydrates by laccase is similar to the peroxidase-catalyzed reaction, the aromatic ring of FA being the initiating site for enzymatic oxidation [25]. It has also been shown that laccase can cross-link whey proteins in the presence of phenolic acid [27]. However, in order to be able to develop new applications for laccases in foods, it is crucial also to understand enzymatic reactions on proteins at the molecular level. At present, laccase-catalyzed reactions resulting in oxidation of proteins are poorly understood. Very Laccase-catalyzed polymerization of tyrosine and tyrosine-containing peptides was studied in the presence and absence of ferulic acid (FA). Advanced spectroscopic methods such as MALDI-TOF MS, EPR, FTIR microscopy and HPLC-fluorescence, as well as more conventional analytical tools: oxygen consumption measurements and SDS ⁄ PAGE were used in the reaction mechanism studies. Laccase was found to oxidize tyrosine and tyrosine-containing peptides, with consequent polymerization of the compounds. The covalent linkage connecting the compounds was found to be an ether bond. Only small amounts of dityrosine bonds were detected in the polymers. When FA was added to the reaction mixtures, it was found to be incorporated into the polymer structure. Thus, in addition to homopolymers, different heteropolymers containing two or four FA residues were formed in the reactions.
This paper aims to describe the patient enrollment system and implementation strategy for the new nationwide Danish Centre for Strategic Research in Type 2 Diabetes (DD2) project. The paper will also describe the design, current content, and pilot testing of the DD2 registration form. The challenge of the DD2 project was to construct a registration system functioning in the entire Danish health care system, where new type 2 diabetes patients are initially met, and with the capacity to enroll 200 newly diagnosed diabetes patients per week nationwide. This requires a fast and simple registration that is part of everyday clinical practice in hospital outpatient clinics and general practitioner (GP) clinics. The enrollment system is thus built on a tested, rational design where patients need only one visit and only specific limited data about physical activity, anthropometric measures, and family history of diabetes are collected during a brief patient interview. Later, supplemental data will be extracted by computerized linkage with existing databases. The feasibility of this strategy was verified in a pilot study. For maximum flexibility, three different ways to fill in the DD2 registration form were provided and an interactive webpage was constructed. The DD2 project also involves collection of blood and urine samples from each diabetes patient, to be stored in a biobank. Clinicians may obtain the samples themselves or refer patients to the nearest clinical biochemical department. GPs have the additional option of referring patients to the nearest hospital outpatient diabetes clinic to obtain interview data, clinical data, and samples. At present, the enrollment system is in use at 17 hospital outpatient diabetes clinics and 45 GP clinics nationwide, together enrolling 40 new type 2 diabetes patients per week in the DD2 project. A total of 990 patients have now been enrolled and the DD2 is ready to expand nationwide.
Laccase-catalyzed oxidation was able to induce intermolecular cross-links in beta-lactoglobulin, and ferulic acid-mediated laccase-catalyzed oxidation was able to induce intermolecular cross-links in alpha-casein, whereas transglutaminase cross-linked only alpha-casein. In addition, different patterns of laccase-induced oxidative modifications were detected, including dityrosine formation, formation of fluorescent tryptophan oxidation products, and carbonyls derived from histidine, tryptophan, and methionine. Laccase-catalyzed oxidation as well as transglutaminase induced only minor changes in surface tension of the proteins, and the changes could not be correlated to protein cross-linking. The presence of ferulic acid was found to influence the effect of laccase, allowing laccase to form irreducible intermolecular cross-links in beta-lactoglobulin and resulting in proteins exercising higher surface tensions due to cross-linking as well as other oxidative modifications. The outcome of using ferulic acid-mediated laccase-catalyzed oxidation to modify the functional properties of proteinaceous food components or other biosystems is expected to be highly dependent on the protein composition, resulting in different changes of the functional properties.
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