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1.
Neurochem Res ; 49(5): 1322-1330, 2024 May.
Article in English | MEDLINE | ID: mdl-38478218

ABSTRACT

Microdialysis is applied in neurointensive care to monitor cerebral glucose metabolism. If recoverable, macromolecules may also serve as biomarkers in brain disease and provide clues to their passage across the blood-brain barrier. Our study aimed to investigate the in vitro recovery of human micro- and macromolecules using microdialysis catheters and perfusion fluids approved for clinical use. In vitro microdialysis of a bulk solution containing physiological or supraphysiological concentrations of glucose, lactate, pyruvate, human IgG, serum albumin, and hemoglobin was performed using two different catheters and perfusion fluids. One had a membrane cut-off of 20 kDa and was used with a standard CNS perfusion fluid, and the other had a membrane cut-off of 100 kDa and was perfused with the same solution supplemented with dextran. The flow rate was 0.3 µl/min. We used both push and push-pull methods. Dialysate samples were collected at 2-h intervals for 6 h and analyzed for relative recovery of each substance. The mean relative recovery of glucose, pyruvate, and lactate was > 90% in all but two sets of experiments. In contrast, the relative recovery of human IgG, serum albumin, and hemoglobin from both bulk solutions was below the lower limit of quantification (LLOQ). Using a push-pull method, recovery of human IgG, serum albumin, and hemoglobin from a bulk solution with supraphysiological concentrations were above LLOQ but with low relative recovery (range 0.9%-1.6%). In summary, exchanging the microdialysis setup from a 20 kDa catheter with a standard perfusion fluid for a 100 kDa catheter with a perfusion solution containing dextran did not affect the relative recovery of glucose and its metabolites. However, it did not result in any useful recovery of the investigated macromolecules at physiological levels, either with or without a push-pull pump system.


Subject(s)
Brain Injuries , Dextrans , Humans , Brain Injuries/metabolism , Microdialysis/methods , Perfusion/methods , Glucose/metabolism , Lactates , Pyruvates , Serum Albumin , Hemoglobins , Immunoglobulin G
2.
J Clin Ultrasound ; 52(5): 548-557, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38488675

ABSTRACT

PURPOSE: To investigate power Doppler (PD) activity and tendon structure (between the injured and contralateral limb) in patients with unilateral patellar tendinopathy (PT) using ultrasonography (US). Secondly, the aim was to determine the intra-rater reliability of the PD activity and tendon structure. METHODS: This study analyzed US baseline data from 57 male participants with symptomatic unilateral PT who had been enrolled in one of two randomized clinical trials. Data were analyzed to examine if systematic differences existed between injured and contralateral limbs using Fiji ImageJ. RESULTS: The PD activity of the symptomatic tendon was larger 25.6 (Q1 = 14.9; Q3 = 41.6) mm2 than the asymptomatic 0 (Q1 = 0.0; Q3 = 0.0) mm2 (p < 0.001). There was a significantly greater tendon thickness at the proximal (2.5 mm 95% CI [2.0; 3.0]), mid (0.8 mm 95% CI [0.5; 1.1]), and distal (0.2 mm 95% CI [0.1; 0.4]) part of the tendon for the symptomatic compared to the asymptomatic tendon. Intra-rater reliability for PD activity and tendon structure ranged from moderate-to-excellent (0.74; 0.99). CONCLUSION: These results provide mean estimates for tendon thickness of symptomatic and asymptomatic tendons, that can be used for clinicians to reliably estimate pathological tendon thickness.


Subject(s)
Patellar Ligament , Tendinopathy , Humans , Male , Patellar Ligament/diagnostic imaging , Tendinopathy/diagnostic imaging , Adult , Reproducibility of Results , Ultrasonography/methods , Ultrasonography, Doppler/methods , Middle Aged , Young Adult
3.
Redox Biol ; 67: 102873, 2023 11.
Article in English | MEDLINE | ID: mdl-37688976

ABSTRACT

Oxidative stress plays a vital role for the adaptive responses to physical training. However, excessive oxidative stress can precipitate cellular damage, necessitating protective mechanisms to mitigate this effect. Glucosinolates, found predominantly in cruciferous vegetables, can be converted into isothiocyanates, known for their antioxidative properties. These compounds activate crucial antioxidant defence pathways and support mitochondrial function and protein integrity under oxidative stress, in both Nrf2-dependent and independent manners. We here administered glucosinolate-rich broccoli sprouts (GRS), in a randomized double-blinded cross-over fashion to 9 healthy subjects in combination with daily intense exercise training for 7 days. We found that exercise in combination with GRS significantly decreased the levels of carbonylated proteins in skeletal muscle and the release of myeloperoxidase into blood. Moreover, it lowered lactate accumulation during submaximal exercise, and attenuated the severe nocturnal hypoglycaemic episodes seen during the placebo condition. Furthermore, GRS in combination with exercise improved physical performance, which was unchanged in the placebo condition.


Subject(s)
Brassica , Glucosinolates , Humans , Glucosinolates/metabolism , Brassica/metabolism , Isothiocyanates , Oxidative Stress , Antioxidants/metabolism
4.
Osteoporos Int ; 32(1): 63-73, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32681362

ABSTRACT

Studying 12,839 fracture cases and 91,426 controls, we found that fractures of the spine and hip are associated with clinically important HRQoL deficits up to 5 years post-fracture. Fracture cases with a low educational attainment are more likely to report very low HRQoL due to a low pre-fracture HRQoL. INTRODUCTION: The aim of this study was to explore the short-term and long-term impact of fractures on health-related quality of life (HRQoL) and to study the effect of educational attainment as a proxy for socio-economic status (SES) on post-fracture HRQoL. METHODS: In a population-based survey including 12,839 fracture cases and 91,426 controls, HRQoL was measured using the physical component score (PCS) and the mental component score (MCS) of the 12-Item Short Form Health Survey (SF-12). Information about fractures, age, sex, ethnicity, comorbidity and SES was obtained from national registers. Multiple regression analysis was conducted to measure the mean HRQoL difference, termed deficit, between non-fracture controls and fracture cases (all fractures combined and fractures at six different skeletal sites). RESULTS: PCS and MCS were significantly lower among fracture cases than among controls. Statistically and clinically important PCS deficits (≥ 5 points) were observed among people with fractures of the spine and hip up to 5 years post-fracture and among people with upper arm fractures up to 1 year post-fracture. Greater deficits were observed for MCS but not for PCS in post-fracture HRQoL in the low than in the high SES group. CONCLUSION: Fractures of the spine and hip are associated with clinically important deficits in physical HRQoL up to 5 years post-fracture. Low educational attainment widened the gap in mental but not in physical post-fracture HRQoL. However, due to low pre-fracture PCS and MCS, people with a low educational attainment and fractures were more likely to report very low HRQoL post-fracture.


Subject(s)
Fractures, Bone , Frailty , Quality of Life , Economic Status , Fractures, Bone/complications , Fractures, Bone/epidemiology , Health Surveys , Humans , Spine
6.
Front Physiol ; 10: 730, 2019.
Article in English | MEDLINE | ID: mdl-31258485

ABSTRACT

Background: Hyperoxia (HYPER) increases O2 carrying capacity resulting in a higher O2 delivery to the working muscles during exercise. Several lines of evidence indicate that lactate metabolism, power output, and endurance are improved by HYPER compared to normoxia (NORM). Since HYPER enables a higher exercise power output compared to NORM and considering the O2 delivery limitation at exercise intensities near to maximum, we hypothesized that hyperoxic-supplemented high-intensity interval training (HIIT) would upregulate muscle mitochondrial oxidative capacity and enhance endurance cycling performance compared to training in normoxia. Methods: 23 trained cyclists, age 35.3 ± 6.4 years, body mass 75.2 ± 9.6 kg, height 179.8 ± 7.9 m, and VO2max 4.5 ± 0.7 L min-1 performed 6 weeks polarized and periodized endurance training on a cycle ergometer consisting of supervised HIIT sessions 3 days/week and additional low-intensity training 2 days/week. Participants were randomly assigned to either HYPER (FIO2 0.30; n = 12) or NORM (FIO2 0.21; n = 11) breathing condition during HIIT. Mitochondrial respiration in permeabilized fibers and isolated mitochondria together with maximal and submaximal VO2, hematological parameters, and self-paced endurance cycling performance were tested pre- and posttraining intervention. Results: Hyperoxic training led to a small, non-significant change in performance compared to normoxic training (HYPER 6.0 ± 3.7%, NORM 2.4 ± 5.0%; p = 0.073, ES = 0.32). This small, beneficial effect on the self-paced endurance cycling performance was not explained by the change in VO2max (HYPER 1.1 ± 3.8%, NORM 0.0 ± 3.7%; p = 0.55, ES = 0.08), blood volume and hemoglobin mass, mitochondrial oxidative phosphorylation capacity (permeabilized fibers: HYPER 27.3 ± 46.0%, NORM 16.5 ± 49.1%; p = 0.37, ES = 3.24 and in isolated mitochondria: HYPER 26.1 ± 80.1%, NORM 15.9 ± 73.3%; p = 0.66, ES = 0.51), or markers of mitochondrial content which were similar between groups post intervention. Conclusions: This study showed that 6 weeks hyperoxic-supplemented HIIT led to marginal gain in cycle performance in already trained cyclists without change in VO2max, blood volume, hemoglobin mass, mitochondrial oxidative phosphorylation capacity, or exercise efficiency. The underlying mechanisms for the potentially meaningful performance effects of hyperoxia training remain unexplained and may raise ethical questions for elite sport.

7.
Acta Physiol (Oxf) ; 225(1): e13110, 2019 01.
Article in English | MEDLINE | ID: mdl-29863764

ABSTRACT

AIM: We examined the Fick components together with mitochondrial O2 affinity (p50mito ) in defining O2 extraction and O2 uptake during exercise with large and small muscle mass during normoxia (NORM) and hyperoxia (HYPER). METHODS: Seven individuals performed 2 incremental exercise tests to exhaustion on a bicycle ergometer (BIKE) and 2 on a 1-legged knee extension ergometer (KE) in NORM or HYPER. Leg blood flow and VO2 were determined by thermodilution and the Fick method. Maximal ADP-stimulated mitochondrial respiration (OXPHOS) and p50mito were measured ex vivo in isolated mitochondria. Mitochondrial excess capacity in the leg was determined from OXPHOS in permeabilized fibres and muscle mass measured with magnetic resonance imaging in relation to peak leg O2 delivery. RESULTS: The ex vivo p50mito increased from 0.06 ± 0.02 to 0.17 ± 0.04 kPa with varying substrate supply and O2 flux rates from 9.84 ± 2.91 to 16.34 ± 4.07 pmol O2 ·s-1 ·µg-1 respectively. O2 extraction decreased from 83% in BIKE to 67% in KE as a function of a higher O2 delivery and lower mitochondrial excess capacity. There was a significant relationship between O2 extraction and mitochondrial excess capacity and p50mito that was unrelated to blood flow and mean transit time. CONCLUSION: O2 extraction varies with mitochondrial respiration rate, p50mito and O2 delivery. Mitochondrial excess capacity maintains a low p50mito which enhances O2 diffusion from microvessels to mitochondria during exercise.


Subject(s)
Exercise/physiology , Mitochondria/metabolism , Muscle, Skeletal/metabolism , Oxygen Consumption/physiology , Oxygen/metabolism , Adult , Body Composition , Exercise Test , Female , Humans , Male , Middle Aged , Young Adult
8.
Breast ; 43: 113-119, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30544058

ABSTRACT

OBJECTIVES: Hepatic arterial treatment (HAT) for liver metastases in patients with metastatic breast cancer (MBC) has only been investigated in few studies. MATERIALS AND METHODS: Two phase II trials were initiated simultaneously to evaluate capecitabine in combination with oxaliplatin in patients with MBC and liver metastases. These two trials are reported together. Continuous capecitabine (1300 mg/m2) was combined with oxaliplatin (85 mg/m2) alternating between systemic treatment and HAT followed by degradable starch microspheres with EmboCept® S every second week. Four patients participated in a pharmacokinetic analysis of oxaliplatin. Each patient had samples taken when receiving oxaliplatin systemically and as HAT with and without EmboCept® S. RESULTS: Totally, 52 patients received HAT: 14 with liver metastases only and 38 patients with additional limited metastatic disease. The patients had previously received a median of 2 (range 0-6) chemotherapeutic regimens for MBC. The response rate was 42.3% (95% confidence interval (CI) 28.7-56.8%) with 7.7% complete and 34.6% partial responses. Median progression free survival was 10.8 months (95% CI 6.9-14.7 months) and median overall survival 27.6 months (95% CI 20.4-34.8 months). The toxicity was moderate with hand-foot syndrome (15.4%), neuropathy (9.6%), fatigue (9.6%), and abdominal pain (9.6%) being the most common grade 3 adverse events. There was no clear difference between systemic blood concentrations of oxaliplatin when given systemic or as HAT. CONCLUSION: HAT oxaliplatin in combination with capecitabine is safe and efficient in patients with MBC. The results are promising with high response rates and a long median progression free and overall survival.


Subject(s)
Adenocarcinoma/therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/therapy , Chemoembolization, Therapeutic/methods , Hepatic Artery , Liver Neoplasms/therapy , Abdominal Pain/chemically induced , Adenocarcinoma/secondary , Adult , Aged , Breast Neoplasms/pathology , Capecitabine/administration & dosage , Fatigue/chemically induced , Female , Hand-Foot Syndrome/etiology , Humans , Liver Neoplasms/secondary , Middle Aged , Oxaliplatin/administration & dosage , Peripheral Nervous System Diseases/chemically induced , Progression-Free Survival
9.
Clin Chim Acta ; 487: 107-111, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30240586

ABSTRACT

BACKGROUND: Cell free DNA (cfDNA) has shown promising utility as prognostic biomarker for patients with colorectal cancer (CRC), with an ongoing need to optimize and validate the laboratory methodology. Here, we report our optimization and validation of a direct fluorescent assay and display the potential utility in patients with colorectal cancer. METHODS: Plasma cfDNA was analyzed by a direct fluorescent assay (DFA) and compared to quantification by droplet digital PCR (ddPCR). For clinical validation, baseline blood samples were available for a total of 273 patients from six different Nordic trials, covering patients with locally advanced rectal cancer (n = 176, cohorts A + B), liver limited metastatic CRC (n = 75C + D) and wide spread metastatic CRC (n = 22 E + F). RESULTS: Validating the DFA analysis with ddPCR revealed a strong correlation with an R2 of 0.81. For the clinical cohorts, the levels of cfDNA were: 0.8 ng/uL (95%CI 0.75-0.83) (A + B), 0.93 ng/uL (95%CI 0.86-1.02) (C + D) and 1.2 ng/uL (95%CI 0.85-1.47) (E + F), respectively (p < 0.01). All cohorts of colorectal cancer had higher levels of cell free DNA than healthy individuals (n = 94) (p < 0.01). CONCLUSION: Analysis of cell free DNA by a direct fluorescent assay could be an attractive laboratory option for a rapid inexpensive quantification of cell free DNA.


Subject(s)
Cell-Free Nucleic Acids/blood , Colorectal Neoplasms/blood , DNA, Neoplasm/blood , Fluorescent Antibody Technique, Direct , Cell-Free Nucleic Acids/genetics , Cohort Studies , Colorectal Neoplasms/genetics , DNA, Neoplasm/genetics , Humans , Polymerase Chain Reaction
10.
Eur J Cancer Care (Engl) ; 27(3): e12840, 2018 May.
Article in English | MEDLINE | ID: mdl-29668067

ABSTRACT

The aim of this study was to compare health behaviours (smoking, alcohol consumption, physical activity and diet), to explore social inequality in these behaviours among cancer survivors and individuals with no history of cancer, respectively, and to study the impact of time since diagnosis on cancer survivors' health behaviours. Data from the Danish National Health Survey from 2013 were linked with data from the Danish Cancer Registry to identify all cancer diagnoses among the respondents during the period 1945-2012. In total, 11,166 cancer survivors and 151,117 individuals with no history of cancer were included. Cancer survivors smoked less and had a more sedentary lifestyle than individuals with no history of cancer. In relation to alcohol and dietary habits, no differences were found between the groups. Wide variations in health behaviours were seen across cancer sites, and in particular lung, bladder and oral cancer survivors had poor health behaviours. We found a clear social gradient in cancer survivors' health behaviours which reveals the need for greater focus on socially differentiated initiatives within prevention and patient education for cancer survivors. Our study revealed rather blurred results in relation to identifying the optimal timing for health-related behavioural interventions in cancer survivors.


Subject(s)
Cancer Survivors/statistics & numerical data , Health Behavior , Adult , Aged , Alcohol Drinking , Cross-Sectional Studies , Denmark , Exercise , Feeding Behavior , Female , Humans , Logistic Models , Male , Middle Aged , Sedentary Behavior , Smoking , Socioeconomic Factors
11.
Ann Oncol ; 29(3): 610-615, 2018 03 01.
Article in English | MEDLINE | ID: mdl-29253083

ABSTRACT

Background: Treatment of patients with locally advanced rectal cancer (LARC) is based on a combination of chemo-radiotherapy (CRT) and surgery. The rate of distant recurrences remains over 25%. Circulating cell-free DNA (cfDNA) in plasma is a mixture of normal and cancer-specific DNA segments and is a promising biomarker in patients with colorectal cancer. The aim of our study was to investigate plasma cfDNA as a prognostic marker for outcome in patients with LARC treated with neoadjuvant CRT and surgery. Patients and methods: In total, 123 patients with LARC were included in 2 biomarker studies. Patients were treated with neoadjuvant CRT before TME surgery. Fifty-two (42%) of the patients received induction chemotherapy with capecitabine + oxaliplatin. Total cfDNA was measured by direct fluorescent assay in EDTA plasma samples obtained at baseline, after induction chemotherapy, and after CRT. Serial samples 5 years after surgery were collected in 51 patients (41%). Results: Median follow-up was 55 months. Distant or local recurrence was seen in 30.9% of the patients. Patients with baseline cfDNA levels above the 75th quartile had a higher risk of local or distant recurrence and shorter time to recurrence compared with patients with plasma cfDNA below the 75th percentile (HR = 2.48, 95% CI: 1.3-4.8, P = 0.007). The same applied to disease-free survival (DFS) (HR = 2.43, 95% CI: 1.27-4.7, P = 0.015). In multivariate analysis, a high cfDNA level was significantly associated with time to progression and DFS. During follow-up, the association remained significant regardless of time point for sample analysis. Conclusion: We have demonstrated an association between a high baseline plasma level of cfDNA and increased risk of recurrence, shorter time to recurrence, and shorter DFS in patients with LARC. Consequently, cfDNA could potentially improve pre- and post-treatment risk assessment and facilitate individualized therapy for patients with LARC.


Subject(s)
Adenocarcinoma/blood , Adenocarcinoma/therapy , Biomarkers, Tumor/blood , Circulating Tumor DNA/blood , Rectal Neoplasms/blood , Rectal Neoplasms/therapy , Adenocarcinoma/mortality , Adult , Aged , Chemoradiotherapy, Adjuvant/mortality , Combined Modality Therapy/mortality , Digestive System Surgical Procedures/mortality , Disease-Free Survival , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Neoadjuvant Therapy/mortality , Rectal Neoplasms/mortality
12.
Scand J Med Sci Sports ; 25 Suppl 4: 135-43, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26589127

ABSTRACT

We recently reported the circulatory and muscle oxidative capacities of the arm after prolonged low-intensity skiing in the arctic (Boushel et al., 2014). In the present study, leg VO2 was measured by the Fick method during leg cycling while muscle mitochondrial capacity was examined on a biopsy of the vastus lateralis in healthy volunteers (7 male, 2 female) before and after 42 days of skiing at 60% HR max. Peak pulmonary VO2 (3.52 ± 0.18 L.min(-1) pre vs 3.52 ± 0.19 post) and VO2 across the leg (2.8 ± 0.4L.min(-1) pre vs 3.0 ± 0.2 post) were unchanged after the ski journey. Peak leg O2 delivery (3.6 ± 0.2 L.min(-1) pre vs 3.8 ± 0.4 post), O2 extraction (82 ± 1% pre vs 83 ± 1 post), and muscle capillaries per mm(2) (576 ± 17 pre vs 612 ± 28 post) were also unchanged; however, leg muscle mitochondrial OXPHOS capacity was reduced (90 ± 3 pmol.sec(-1) .mg(-1) pre vs 70 ± 2 post, P < 0.05) as was citrate synthase activity (40 ± 3 µmol.min(-1) .g(-1) pre vs 34 ± 3 vs P < 0.05). These findings indicate that peak muscle VO2 can be sustained with a substantial reduction in mitochondrial OXPHOS capacity. This is achieved at a similar O2 delivery and a higher relative ADP-stimulated mitochondrial respiration at a higher mitochondrial p50. These findings support the concept that muscle mitochondrial respiration is submaximal at VO2max , and that mitochondrial volume can be downregulated by chronic energy demand.


Subject(s)
Lung/physiology , Mitochondria, Muscle/physiology , Oxygen Consumption , Quadriceps Muscle/blood supply , Quadriceps Muscle/physiology , Skiing/physiology , Adult , Capillaries/anatomy & histology , Cell Respiration , Citrate (si)-Synthase/metabolism , Exercise Test , Female , Humans , Male , Middle Aged , Mitochondrial Size , Oxidative Phosphorylation , Oxygen/blood , Quadriceps Muscle/cytology , Regional Blood Flow
13.
Eur J Pharm Sci ; 77: 303-13, 2015 Sep 18.
Article in English | MEDLINE | ID: mdl-26091569

ABSTRACT

Desvenlafaxine is a biopharmaceutics classification system (BCS) class 1 (high solubility, high permeability) and biopharmaceutical drug disposition classification system (BDDCS) class 3, (high solubility, poor metabolism; implying low permeability) compound. Thus the rate-limiting step for desvenlafaxine absorption (i.e. intestinal dissolution or permeation) is not fully clarified. The aim of this study was to investigate whether dissolution and/or intestinal permeability rate-limit desvenlafaxine absorption from an immediate-release formulation (IRF) and Pristiq(®), an extended release formulation (ERF). Semi-mechanistic models of desvenlafaxine were built (using SimCyp(®)) by combining in vitro data on dissolution and permeation (mechanistic part of model) with clinical data (obtained from literature) on distribution and clearance (non-mechanistic part of model). The model predictions of desvenlafaxine pharmacokinetics after IRF and ERF administration were compared with published clinical data from 14 trials. Desvenlafaxine in vivo dissolution from the IRF and ERF was predicted from in vitro solubility studies and biorelevant dissolution studies (using the USP3 dissolution apparatus), respectively. Desvenlafaxine apparent permeability (Papp) at varying apical pH was investigated using the Caco-2 cell line and extrapolated to effective intestinal permeability (Peff) in human duodenum, jejunum, ileum and colon. Desvenlafaxine pKa-values and octanol-water partition coefficients (Do:w) were determined experimentally. Due to predicted rapid dissolution after IRF administration, desvenlafaxine was predicted to be available for permeation in the duodenum. Desvenlafaxine Do:w and Papp increased approximately 13-fold when increasing apical pH from 5.5 to 7.4. Desvenlafaxine Peff thus increased with pH down the small intestine. Consequently, desvenlafaxine absorption from an IRF appears rate-limited by low Peff in the upper small intestine, which "delays" the predicted time to the maximal plasma concentration (tmax), consistent with clinical data. Conversely, desvenlafaxine absorption from the ERF appears rate-limited by dissolution due to the formulation, which tends to negate the influence of pH-dependent permeability on absorption. We suggest that desvenlafaxine Peff is mainly driven by transcellular diffusion of the unionized form. In the case of desvenlafaxine, poor metabolism does not imply low intestinal permeability, as indicated by the BDDCS, merely low duodenal/jejunal permeability.


Subject(s)
Desvenlafaxine Succinate/pharmacokinetics , Intestinal Absorption , Models, Biological , Serotonin and Noradrenaline Reuptake Inhibitors/pharmacokinetics , Cell Line, Tumor , Delayed-Action Preparations , Desvenlafaxine Succinate/administration & dosage , Humans , In Vitro Techniques , Permeability , Serotonin and Noradrenaline Reuptake Inhibitors/administration & dosage , Solubility
14.
Langmuir ; 30(29): 8687-96, 2014 Jul 29.
Article in English | MEDLINE | ID: mdl-25026245

ABSTRACT

Low-molecular-weight (LMW) emulsifiers are used to promote controlled destabilization in many dairy-type emulsions in order to obtain stable foams in whippable products. The relation between fat globule aggregation induced by three LMW emulsifiers, lactic acid ester of monoglyceride (LACTEM), saturated monoglyceride (GMS), and unsaturated monoglyceride (GMU) and their effect on interfacial protein displacement was investigated. It was found that protein displacement by LMW emulsifiers was not necessary for fat globule aggregation in emulsions, and conversely fat globule aggregation was not necessarily accompanied by protein displacement. The three LMW emulsifiers had very different effects on emulsions. LACTEM induced shear instability of emulsions, which was accompanied by protein displacement. High stability was characteristic for emulsions with GMS where protein was displaced from the interface. Emulsions containing GMU were semisolid, but only low concentrations of protein were detected in the separated serum phase. The effects of LACTEM, GMS, and GMU may be explained by three different mechanisms involving formation of interfacial α-gel, pickering stabilization and increased exposure of bound casein to the water phase. The latter may facilitate partial coalescence. Stabilizing hydrocolloids did not have any effect on the LMW emulsifiers' ability to induce protein displacement.


Subject(s)
Caseins/chemistry , Chelating Agents/chemistry , Emulsifying Agents/chemistry , Lactic Acid/chemistry , Monoglycerides/chemistry , Emulsions , Esters , Food Technology , Gels , Rheology
15.
Meat Sci ; 96(1): 617-22, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24045062

ABSTRACT

The effects of diacylglycerols (DAG), pork back fat and sunflower oil on water and fat mobility in fermented sausages were studied with (1)H NMR relaxometry. The added fat affected the physicochemical parameters weight loss, water activity, moisture content and moisture content on a defatted-dry-matter basis of reduced-fat non-acid fermented sausages. The weight losses were the lowest in sausages prepared with DAG and sunflower oil, which resulted in higher water activity compared to sausages prepared with back fat. The relaxation times related to fat mobility differed between fat types and increased in the order: control

Subject(s)
Diglycerides/chemistry , Fermentation , Meat Products/analysis , Plant Oils/chemistry , Animals , Chemical Phenomena , Desiccation , Food Handling/methods , Hydrogen-Ion Concentration , Magnetic Resonance Spectroscopy , Sunflower Oil , Swine , Water/analysis
16.
Br J Dermatol ; 170(2): 408-14, 2014 Feb.
Article in English | MEDLINE | ID: mdl-23909409

ABSTRACT

BACKGROUND: Alitretinoin (9-cis-retinoic acid, Toctino(®) ) has been marketed recently for oral therapy for chronic hyperkeratotic hand eczema. As alitretinoin is highly lipophilic and metabolized mainly in the liver, it is currently considered to be contraindicated in patients with liver disease. However, the pharmacokinetics and metabolism of alitretinoin have not been studied in these patients. OBJECTIVES: To study the single-dose pharmacokinetics and metabolism of alitretinoin and its metabolites in patients with cirrhosis following oral administration. METHODS: Eight patients with cirrhosis and eight matched volunteer healthy controls were given a single 30-mg oral dose of alitretinoin. Blood and urine samples were collected during the following 24-h study period. Samples were analysed for alitretinoin and for known metabolites using reverse-phase high-performance liquid chromatography. The pharmacokinetics were then evaluated using standard noncompartmental models. RESULTS: No significant differences were found between healthy controls and patients with cirrhosis when analysing the pharmacokinetic parameters of alitretinoin and its metabolites. Thus, the mean half-lives of alitretinoin were 5·3 and 5·6 h (P = 0.733) and the oral clearances were 1·92 and 1·39 L h(-1) kg(-1) (P = 0·243) in the patient group and the healthy control group, respectively. CONCLUSIONS: The metabolism and pharmacokinetics of alitretinoin following oral administration of the recommended dose of 30 mg for the treatment of severe hand eczema were similar in patients with cirrhosis and in healthy controls. If indicated, alitretinoin can be used in these patients with careful and close monitoring.


Subject(s)
Dermatologic Agents/pharmacokinetics , Liver Cirrhosis/metabolism , Tretinoin/pharmacokinetics , Administration, Oral , Aged , Alitretinoin , Area Under Curve , Dermatologic Agents/administration & dosage , Eczema/drug therapy , Female , Hand Dermatoses/drug therapy , Humans , Male , Middle Aged , Tretinoin/administration & dosage
17.
Metab Brain Dis ; 28(2): 179-82, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23099996

ABSTRACT

Acute liver failure patients with a persistence of hyperammonemia are at an increased risk of intracranial hypertension due to development of brain oedema. In vitro studies of brain tissue and cell cultures that indicates that exposure to ammonium inhibits enzymatic activity in the tricarboxylic acid cycle, induces substrate depletion through marked glutamate utilization for glutamine synthesis and leads to mitochondrial dysfunction. In patients with acute liver failure cerebral microdialysis studies show a linear correlation between the lactate to pyruvate ratio and the glutamine concentration, as well as to some of the adenosine triphosphate degradation products. However, clinical observations of cerebral exchange rates of oxygen, glucose, lactate and amino acids challenge the interpretation of these findings. In this review the conflicting data of cerebral metabolism during acute liver failure is discussed.


Subject(s)
Brain Chemistry/physiology , Brain/metabolism , Liver Failure, Acute/metabolism , Amino Acids/metabolism , Ammonia/metabolism , Animals , Humans , Hyperammonemia/metabolism , Lactic Acid/metabolism , Oxidation-Reduction , Pyruvic Acid/metabolism
18.
Ann Oncol ; 23(10): 2627-2633, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22473488

ABSTRACT

BACKGROUND: Preoperative chemoradiation in patients with locally advanced rectal cancer has no impact on overall survival (OS) and distant recurrences. The aim of the study was to evaluate local downstaging, toxicity and long-term outcome in patients with locally advanced rectal cancer after induction therapy with capecitabine and oxaliplatin (CAPEOX) followed by radiotherapy concomitant with capecitabine [chemoradiotherapy (CRT)] before total mesorectal excision (TME). PATIENTS AND METHODS: Patients with T4 tumors, all T3N+ tumors or T3 tumors involving or with a distance ≤1 mm to the mesorectal fascia were included. Patients were planned for two cycles of CAPEOX followed by radiotherapy concomitant with capecitabine. TME was carried out 6 weeks after the completion of CRT. RESULTS: Of 84 consecutively admitted patients starting induction CAPEOX, 77 patients underwent surgery. R0 resection was seen in 94% and T downstaging in 69%. In the intention-to-treat group, pathological complete response was seen in 23%. Five-year disease-free survival (DFS) and OS were 63% [95% confidence interval (CI), 52.2% to 73.7%] and 67% (95% CI, 56.1% to 77.3%), respectively. Grade 3/4 toxicity was seen in 18%, and four deaths occurred within 2 months of therapy. CONCLUSION: Induction chemotherapy before CRT and surgery showed a high local control rate and promising long-term outcome as OS and DFS.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Rectal Neoplasms/therapy , Capecitabine , Combined Modality Therapy , Deoxycytidine/administration & dosage , Deoxycytidine/analogs & derivatives , Female , Fluorouracil/administration & dosage , Fluorouracil/analogs & derivatives , Humans , Male , Organoplatinum Compounds/administration & dosage , Oxaliplatin , Rectal Neoplasms/drug therapy , Rectal Neoplasms/radiotherapy , Rectal Neoplasms/surgery
20.
Clin Physiol Funct Imaging ; 31(3): 169-74, 2011 May.
Article in English | MEDLINE | ID: mdl-21143366

ABSTRACT

BACKGROUND AND AIMS: We investigated whether in patients with liver cirrhosis reduced muscle strength is related to dysfunction of muscle mitochondria. METHODS: The mitochondrial respiratory capacity of the tibial anterior muscle was evaluated in seven patients and eight healthy control subjects by 31P nuclear magnetic resonance spectroscopy (31PMRS) to express ATP turnover in vivo and by respirometry of permeabilized fibres from the same muscle to express the in vitro capacity for oxygen consumption. RESULTS: Maximal voluntary contraction force for plantar extension was low in the patients (46% of the control value; P < 0.05), but neither the capacity for mitochondrial ATP synthesis, V(max-ATP) (0.38 ± 0.26 vs. 0.50 ± 0.07 mM s(-1) ; P = 0.13) nor the in vitro VO(2max) (0.52 ± 0.21 vs. 0.48 ± 0.21 µmol O2 (min g wet wt.)(-1) P = 0.25) were lowered correspondingly. Also, the activity of citrate synthesis and the respiratory chain complexes II and IV were similar in patients and controls. However during the contractions, the contribution to initial anaerobic ATP production from glycolysis relative to that from PCr was reduced in the patients (0.73 ± 0.22 vs. 0.99 ± 0.09; P < 0.01). CONCLUSIONS: These results demonstrate that the markedly lower capacity for force generation in patients with liver cirrhosis is unrelated to their capacity for muscle ATP turnover, but the attenuated initial acceleration of anaerobic glycolysis suggests that these patients could be affected by a central limitation to force generation.


Subject(s)
Adenosine Triphosphate/metabolism , Central Nervous System/physiopathology , Energy Metabolism , Liver Cirrhosis/physiopathology , Mitochondria, Muscle/metabolism , Muscle Contraction , Muscle Strength , Muscle, Skeletal/physiopathology , Adult , Analysis of Variance , Case-Control Studies , Female , Glycolysis , Humans , Least-Squares Analysis , Linear Models , Liver Cirrhosis/metabolism , Magnetic Resonance Spectroscopy , Male , Middle Aged , Muscle, Skeletal/innervation , Muscle, Skeletal/metabolism , Oxygen Consumption , Phosphocreatine/analogs & derivatives , Phosphocreatine/metabolism
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