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Σάββατο 18 Νοεμβρίου 2017
Concomitant external pneumatic compression treatment with consecutive days of high intensity interval training reduces markers of proteolysis
Abstract
Purpose
To compare the effects of external pneumatic compression (EPC) and sham when used concurrently with high intensity interval training (HIIT) on performance-related outcomes and recovery-related molecular measures.
Methods
Eighteen recreationally endurance-trained male participants (age: 21.6 ± 2.4 years, BMI: 25.7 ± 0.5 kg/m2, VO2peak: 51.3 ± 0.9 mL/kg/min) were randomized to balanced sham and EPC treatment groups. Three consecutive days of HIIT followed by EPC/sham treatment (Days 2–4) and 3 consecutive days of recovery (Days 5–7) with EPC/sham only on Days 5–6 were employed. Venipuncture, flexibility and pressure-to-pain threshold (PPT) measurements were made throughout. Vastus lateralis muscle was biopsied at PRE (i.e., Day 1), 1-h post-EPC/sham treatment on Day 2 (POST1), and 24-h post-EPC/sham treatment on Day 7 (POST2). 6-km run time trial performance was tested at PRE and POST2.
Results
No group × time interaction was observed for flexibility, PPT, or serum measures of creatine kinase (CK), hsCRP, and 8-isoprostane. However, there was a main effect of time for serum CK (p = 0.005). Change from PRE in 6-km run times at POST2 were not significantly different between groups. Significant between-groups differences existed for change from PRE in atrogin-1 mRNA (p = 0.018) at the POST1 time point (EPC: − 19.7 ± 8.1%, sham: + 7.7 ± 5.9%) and atrogin-1 protein concentration (p = 0.013) at the POST2 time point (EPC: − 31.8 ± 7.5%, sham: + 96.0 ± 34.7%). In addition, change from PRE in poly-Ub proteins was significantly different between groups at both the POST1 (EPC: − 26.0 ± 10.3%, sham: + 34.8 ± 28.5%; p = 0.046) and POST2 (EPC: − 33.7 ± 17.2%, sham: + 21.4 ± 14.9%; p = 0.037) time points.
Conclusions
EPC when used concurrently with HIIT and in subsequent recovery days reduces skeletal muscle markers of proteolysis.
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Acute effects of repeated cycling sprints in hypoxia induced by voluntary hypoventilation
Abstract
Purpose
This study aimed to investigate the acute responses to repeated-sprint exercise (RSE) in hypoxia induced by voluntary hypoventilation at low lung volume (VHL).
Methods
Nine well-trained subjects performed two sets of eight 6-s sprints on a cycle ergometer followed by 24 s of inactive recovery. RSE was randomly carried out either with normal breathing (RSN) or with VHL (RSH-VHL). Peak (PPO) and mean power output (MPO) of each sprint were measured. Arterial oxygen saturation, heart rate (HR), gas exchange and muscle concentrations of oxy-([O2Hb]) and deoxyhaemoglobin/myoglobin ([HHb]) were continuously recorded throughout exercise. Blood lactate concentration ([La]) was measured at the end of the first (S1) and second set (S2).
Results
There was no difference in PPO and MPO between conditions in all sprints. Arterial oxygen saturation (87.7 ± 3.6 vs 96.9 ± 1.8% at the last sprint) and HR were lower in RSH-VHL than in RSN during most part of exercise. The changes in [O2Hb] and [HHb] were greater in RSH-VHL at S2. Oxygen uptake was significantly higher in RSH-VHL than in RSN during the recovery periods following sprints at S2 (3.02 ± 0.4 vs 2.67 ± 0.5 L min−1 on average) whereas [La] was lower in RSH-VHL at the end of exercise (10.3 ± 2.9 vs 13.8 ± 3.5 mmol.L−1; p < 0.01).
Conclusions
This study shows that performing RSE with VHL led to larger arterial and muscle deoxygenation than with normal breathing while maintaining similar power output. This kind of exercise may be worth using for performing repeated sprint training in hypoxia.
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Glutamine supplementation reduces markers of intestinal permeability during running in the heat in a dose-dependent manner
Abstract
Purpose
To examine the dose–response effects of acute glutamine supplementation on markers of gastrointestinal (GI) permeability, damage and, secondary, subjective symptoms of GI discomfort in response to running in the heat.
Methods
Ten recreationally active males completed a total of four exercise trials; a placebo trial and three glutamine trials at 0.25, 0.5 and 0.9 g kg−1 of fat-free mass (FFM) consumed 2 h before exercise. Each exercise trial consisted of a 60-min treadmill run at 70% of \(\dot {V}_}}\) in an environmental chamber set at 30 °C. GI permeability was measured using ratio of lactulose to rhamnose (L:R) in serum. Plasma glutamine and intestinal fatty acid binding protein (I-FABP) concentrations were determined pre and post exercise. Subjective GI symptoms were assessed 45 min and 24 h post-exercise.
Results
Relative to placebo, L:R was likely lower following 0.25 g kg−1 (mean difference: − 0.023; ± 0.021) and 0.5 g kg−1 (− 0.019; ± 0.019) and very likely following 0.9 g kg− 1 (− 0.034; ± 0.024). GI symptoms were typically low and there was no effect of supplementation.
Discussion
Acute oral glutamine consumption attenuates GI permeability relative to placebo even at lower doses of 0.25 g kg−1, although larger doses may be more effective. It remains unclear if this will lead to reductions in GI symptoms. Athletes competing in the heat may, therefore, benefit from acute glutamine supplementation prior to exercise in order to maintain gastrointestinal integrity.
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Acute and chronic changes in baroreflex sensitivity in hypobaric vs. normobaric hypoxia
Abstract
Normobaric hypoxia (NH) is used as a surrogate for hypobaric hypoxia (HH). Recent studies reported physiological differences between NH and HH. Baroreflex sensitivity (BRS) decreases at altitude or following intense training. However, until now no study compared the acute and chronic changes of BRS in NH vs. HH. First, BRS was assessed in 13 healthy male subjects prior and after 20 h of exposure at 3450 m (study 1), and second in 15 well-trained athletes prior and after 18 days of "live-high train-low" (LHTL) at 2250 m (study 2) in NH vs. HH. BRS decreased (p < 0.05) to the same extent in NH and HH after 20 h of hypoxia and after LHTL. These results confirm that altitude decreases BRS but the decrease is similar between HH and NH. The persistence of this decrease after the cessation of a chronic exposure is new and does not differ between HH and NH. The previously reported physiological differences between NH and HH do not appear strong enough to induce different BRS responses.
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The effects of muscle blood flow restriction during running training on measures of aerobic capacity and run time to exhaustion
Abstract
Purpose
Training with blood flow restriction (BFR) is known to enhance muscle mass and strength during resistance training activities. However, little is known about the BFR effects during aerobic training. This investigation examines the effects of running training performed with or without BFR on physiology and performance.
Method
Sixteen subjects (age 24.9 ± 6.9 years, height 172.9 ± 7.8 cm, weight 75.1 ± 13.8 kg) were assigned to a BFR or control (CON) group for eight sessions of training. Before and after training, subjects completed an incremental test to determine peak running velocity (PRV) maximal oxygen uptake ( \(\dot {V}_{2\hbox{max} }}\) ) and running economy (RE), followed by a time to exhaustion run (TTE) performed at PRV. Training for both groups consisted of progressively increasing volumes of 30-s repetitions completed at 80% of PRV.
Results
The BFR and CON groups reported gains (6.3 ± 3.5 vs 4.0 ± 3.3%) in \(\dot {V}_{2\hbox{max} }}\) following training with only trivial (ES = 0.18) differences between groups. Similarly, PRV and incremental test time increased in both training groups with a small (ES ~ 0.3) additional enhancement in favour of the BFR group. Running economy improved in the BFR group but not in CON (ES = 0.4). TTE also increased in both BFR (27 ± 9%) and CON groups (17 ± 6%) with a small (ES = 0.31) additional benefit in favour of the BFR group.
Conclusions
Using BFR during training appears to confer small but potentially worthwhile improvements in RE, PRV and TTE measures. The improvements following BFR training are likely due to muscular rather than cardiovascular function.
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Voluntary activation and variability during maximal dynamic contractions with aging
Abstract
Whether reduced supraspinal activation contributes to age-related reductions in maximal torque during dynamic contractions is not known. The purpose was to determine whether there are age differences in voluntary activation and its variability when assessed with stimulation at the motor cortex and the muscle during maximal isometric, concentric, and eccentric contractions. Thirty young (23.6 ± 4.1 years) and 31 old (69.0 ± 5.2 years) adults performed maximal isometric, shortening (concentric) and lengthening (eccentric) contractions with the elbow flexor muscles. Maximal isometric contractions were performed at 90° elbow flexion and dynamic contractions at a velocity of 60°/s. Voluntary activation was assessed by superimposing an evoked contraction with transcranial magnetic stimulation (TMS) or with electrical stimulation over the muscle during maximal voluntary contractions (MVCs). Old adults had lower MVC torque during isometric (− 17.9%), concentric (− 19.7%), and eccentric (− 9.9%) contractions than young adults, with less of an age difference for eccentric contractions. Voluntary activation was similar between the three contraction types when assessed with TMS and electrical stimulation, with no age group differences. Old adults, however, were more variable in voluntary activation than young (standard deviation 0.99 ± 0.47% vs. 0.73 ± 0.43%, respectively) to both the motor cortex and muscle, and had greater coactivation of the antagonist muscles during dynamic contractions. Thus, the average voluntary activation to the motor cortex and muscle did not differ with aging; however, supraspinal activation was more variable during maximal dynamic and isometric contractions in the old adults. Lower predictability of voluntary activation may indicate subclinical changes in the central nervous system with advanced aging.
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Bovine colostrum supplementation does not affect plasma I-FABP concentrations following exercise in a hot and humid environment
Abstract
Purpose
To quantify the impact of a 14-day bovine colostrum (BC) supplementation on intestinal cell damage following exercise in a hot and humid environment.
Methods
Ten male participants (20 ± 2 years, VO2max 55.80 ± 3.79 mL kg−1 min−1, 11.81 ± 2.71% body fat) ran for 46 ± 7.75 min at 95% of ventiliatory threshold in 40 °C and 50% RH following a 14-day double-blinded supplementation with either BC or placebo (Plac). Core temperature, skin temperature, heart rate, and rating of perceived exertion were recorded every 5 min during exercise. Blood was taken pre, post, 1 h, and 4 h post exercise. Intestinal cell damage was assessed via intestinal fatty acid binding protein (I-FABP).
Results
I-FABP concentrations were similar between conditions at all time points [pre 989.39 ± 490.88 pg ml−1 (BC) 851.35 ± 450.71 pg ml−1 (Plac) post 1505.10 ± 788.63 pg ml−1 (BC) 1267.12 ± 521.51 pg ml−1 (Plac) 1-h, 1087.77 ± 397.06 pg ml−1 (BC) 997.25 ± 524.74 pg ml−1 (Plac) 4-h, 511.35 ± 243.10 pg ml−1 (BC) 501.46 ± 222.54 pg ml−1 (Plac)]. I-FABP was elevated pre to post exercise for both BC (162 ± 50%) and Plac (162 ± 56%) (p < 0.05). BC had no effect on mean body temperature [beginning 36.11 ± 0.30 °C, ending: 39.52 ± 0.28 °C (BC); beginning:35.96 ± 0.43 °C, ending:39.42 ± 0.38 °C (Plac)].
Conclusions
While BC supplementation may protect against enterocyte damage during exercise in thermonuetral environments, our data suggest that BC supplementation may not be an effective technique for preventing enterocyte damage during exercise when core temperature exceeds 39 °C.
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Exercise and gastrointestinal symptoms: running-induced changes in intestinal permeability and markers of gastrointestinal function in asymptomatic and symptomatic runners
Abstract
Purpose
Athletes frequently experience gastrointestinal (GI) symptoms during training and competition. Although the prevalence of exercise-induced GI symptoms is high, the mechanisms leading to GI distress during exercise are not fully understood. The aim of this study was to identify running-induced changes in intestinal permeability and markers of GI function and investigate their association with gastrointestinal symptoms.
Methods
We recruited 17 active runners who we allocated as either asymptomatic or symptomatic based on their history of experiencing GI symptoms during running. The participants took part in a running test where they were asked to run for 90 min at 80% of their best 10 km race speed. Intestinal permeability was measured at baseline and after the running test. Levels of serum intestinal fatty acid-binding protein (I-FABP), zonulin, bacterial lipopolysaccharide (LPS), and fecal calprotectin were also measured at baseline and after the running test.
Results
Running induced a significant increase in intestinal permeability and serum I-FABP concentration but there were no differences between asymptomatic and symptomatic runners. Serum LPS activity did not change from baseline following the running test but the symptomatic group exhibited higher LPS activity at baseline compared to the asymptomatic runners.
Conclusions
Running for 90 min at a challenging pace causes small intestinal damage and increases intestinal permeability. However, these alterations in GI function do not appear to correlate with the development of GI symptoms during running.
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Open-circuit respirometry: a historical review of portable gas analysis systems
Abstract
Scientists such as physiologists, engineers, and nutritionists have often sought to estimate human metabolic strain during daily activities and physical pursuits. The measurement of human metabolism can involve direct calorimetry as well as indirect calorimetry using both closed-circuit respirometry and open-circuit methods that can include diluted flow chambers and laboratory-based gas analysis systems. For field studies, methods involving questionnaires, pedometry, accelerometery, heart rate telemetry, and doubly labelled water exist, yet portable metabolic gas analysis remains the gold standard for most field studies on energy expenditure. This review focuses on research-based portable systems designed to estimate metabolic rate typically under steady-state conditions by critically examining each significant historical innovation. Key developments include Zuntz's 1906 innovative system, then a significant improvement to this purely mechanical system by the widely adopted Kofranyi–Michaelis device in the 1940s. Later, a series of technical improvements: in electronics lead to Wolf's Integrating Motor Pneumotachograph in the 1950s; in polarographic O2 cells in 1970–1980's allowed on-line oxygen uptake measures; in CO2 cells in 1990s allowed on-line respiratory exchange ratio determination; and in advanced sensors/computing power at the turn of the century led to the first truly breath-by-breath portable systems. Very recent significant updates to the popular Cosmed and Cortex systems and the potential commercial release of the NASA-developed 'PUMA' system show that technological developments in this niche area are still incrementally advancing.
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Optimal pacing and carbohydrate intake strategies for ultramarathons
Abstract
Purpose
The purpose of this research is to determine the pacing and nutrition strategies which minimize completion time and carbohydrate intake for athletes competing in ultramarathon races.
Methods
We present the formulation of a two-phase optimization model. The first-phase mixed-integer nonlinear program (MINLP) determines the minimum completion time subject to the altitude, terrain, and distance of the race, as well as the mass and cardiovascular fitness of the athlete. The second-phase MINLP determines the minimum carbohydrate intake required for the athlete to achieve the completion time prescribed by the first-phase subject to the flow of carbohydrates through the stomach, liver, and muscles. Consequently, the second-phase model provides the optimal pacing and nutrition strategies for a particular athlete for each kilometer of a particular race.
Results
We validate model results for a wide range of athlete parameters by comparing completion times to those reported for two case-study events. We also compare the kilometer-by-kilometer pacing and nutrition strategies prescribed by the model to those of a particular athlete. In all cases, the model results closely match those witnessed in the actual events.
Conclusion
We have developed a baseline metabolic model that provides athletes prescriptive guidance regarding optimal pacing and carbohydrate intake strategies prior to competing in ultramarathon races. Given the highly variable topographical characteristics common to many ultramarathon courses and the potential inexperience of many athletes with such courses, our model provides valuable insight to competitors who might otherwise fail to complete the event due to exhaustion or carbohydrate depletion.
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A random-perturbation therapy in chronic non-specific low-back pain patients: a randomised controlled trial
Abstract
The purpose of the study was to assess the effectiveness of a specific rehabilitation therapy for chronic non-specific low-back pain patients, based on a random/irregular functional perturbation training induced by force disturbances to the spine. Forty patients (20 controls and 20 in the perturbation-based group) finished the whole experimental design. A random-perturbation exercise, which included variable and unpredictable disturbances, was implemented in the therapy of the perturbation-based group (13 weeks, two times per week and 1.5 h per session). The participants of the control group did not receive any specific training. Low-back pain, muscle strength, and neuromuscular control of spine stability were investigated before and after the therapy using the visual analog scale, maximal isometric and isokinetic contractions, nonlinear time series analysis, and by determining the stiffness and damping of the trunk after sudden perturbations. The perturbation-based therapy reduced patient's low-back pain (35%), increased muscle strength (15–22%), and trunk stiffness (13%), while no significant changes were observed in the control group. It can be concluded that the proposed therapy has the potential to enhance trunk muscle capability as well as sensory information processing within the motor system during sudden loading and, as a consequence, improve the stabilization of the trunk.
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Time course of recovery following resistance training leading or not to failure
Abstract
Purpose
To describe the acute and delayed time course of recovery following resistance training (RT) protocols differing in the number of repetitions (R) performed in each set (S) out of the maximum possible number (P).
Methods
Ten resistance-trained men undertook three RT protocols [S × R(P)]: (1) 3 × 5(10), (2) 6 × 5(10), and (3) 3 × 10(10) in the bench press (BP) and full squat (SQ) exercises. Selected mechanical and biochemical variables were assessed at seven time points (from − 12 h to + 72 h post-exercise). Countermovement jump height (CMJ) and movement velocity against the load that elicited a 1 m s−1 mean propulsive velocity (V1) and 75% 1RM in the BP and SQ were used as mechanical indicators of neuromuscular performance.
Results
Training to muscle failure in each set [3 × 10(10)], even when compared to completing the same total exercise volume [6 × 5(10)], resulted in a significantly higher acute decline of CMJ and velocity against the V1 and 75% 1RM loads in both BP and SQ. In contrast, recovery from the 3 × 5(10) and 6 × 5(10) protocols was significantly faster between 24 and 48 h post-exercise compared to 3 × 10(10). Markers of acute (ammonia, growth hormone) and delayed (creatine kinase) fatigue showed a markedly different course of recovery between protocols, suggesting that training to failure slows down recovery up to 24–48 h post-exercise.
Conclusions
RT leading to failure considerably increases the time needed for the recovery of neuromuscular function and metabolic and hormonal homeostasis. Avoiding failure would allow athletes to be in a better neuromuscular condition to undertake a new training session or competition in a shorter period of time.
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Hearing impairment caused by mutations in two different genes responsible for nonsyndromic and syndromic hearing loss within a single family
Abstract
Usher syndrome is rare genetic disorder impairing two human senses, hearing and vision, with the characteristic late onset of vision loss. This syndrome is divided into three types. In all cases, the vision loss is postlingual, while loss of hearing is usually prelingual. The vestibular functions may also be disturbed in Usher type 1 and sometimes in type 3. Vestibular areflexia is helpful in making a proper diagnosis of the syndrome, but, often, the syndrome is misdiagnosed as a nonsyndromic hearing loss. Here, we present a Polish family with hearing loss, which was clinically classified as nonsyndromic. After excluding mutations in the DFNB1 locus, we implemented the next-generation sequencing method and revealed that hearing loss was syndromic and mutations in the USH2A gene indicate Usher syndrome. This research highlights the importance of molecular analysis in establishing a clinical diagnosis of congenital hearing loss.
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The Prevalence of Biopsy-Proven Eosinophilic Esophagitis in Hispanics Undergoing Endoscopy Is Infrequent Compared to Caucasians: A Cross-Sectional Study
Abstract
Introduction
The prevalence of eosinophilic esophagitis (EoE), a chronic, immune-mediated, clinicopathologic, inflammatory disorder, has been well described in the pediatric and adult Caucasian population but not as well studied in the Hispanic population. The major aims of this study are to determine the prevalence and gene expression profile of EoE in these populations.
Methods
This is a retrospective cohort study of patients from two institutions predominantly serving a Hispanic population. Patients included at Los Angeles County Hospital (LACH) had an esophagogastroduodenoscopy (EGD) and esophageal biopsies performed for evaluation of dysphagia and/or food impaction, while patients included from the University Hospital Medical Center of El Paso (UHMCEP) had an EGD and esophageal biopsies performed for any appropriate clinical indication. Gene expression analysis which has been shown to accurately diagnose EOE in Caucasians was performed for 9 patients at UHMCEP to determine its accuracy in Hispanics.
Results
At LACH, 234 patients were included in the study of whom 155 (66.3%) were Hispanic and 22 (9.4%) were Caucasian. 3.2% of the Hispanic patients and 9.1% of the Caucasian patients were diagnosed with EOE with threefold difference. At UHMCEP 1700 patients were included of whom 1350 (79.4%) were Hispanic and 179 (10.5%) were Caucasian. 0.96% of the Hispanic patients and 7.26% of the Caucasian patients were diagnosed with EOE with a sevenfold difference. Gene expression accurately diagnosed EOE in a small number of both Hispanics and Caucasians who underwent analysis.
Conclusions
Hispanic patients at LAC and UMHCEP had a significantly lower prevalence of EOE as compared to Caucasians at these two institutions and a lower prevalence as compared to Caucasians with EOE previously reported in the literature. Gene expression analysis, which has previously been shown to accurately diagnose EOE in Caucasian patients, accurately diagnosed EOE in a small sample of this Hispanic population. Based on this similar gene expression, other factors such as environmental, ethnic, and cultural causes should be investigated to explain the markedly lower prevalence of EOE in Hispanics.
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Out-of-Pocket Cost Is a Barrier to Therapeutic Drug Monitoring in Inflammatory Bowel Disease
Abstract
Background
Therapeutic drug monitoring (TDM) is increasingly performed to optimize biologic therapy in inflammatory bowel disease (IBD). However, patients and physicians may be reluctant to perform TDM due to concerns related to potential out-of-pocket costs.
Aims
The aim of this study was to evaluate patient understanding and attitudes toward TDM in different clinical scenarios with and without potential out-of-pocket costs.
Methods
Adult IBD patients at a tertiary gastroenterology clinic were anonymously surveyed from March to September 2016 to assess their understanding of and willingness to undergo TDM in a variety of clinical scenarios, both with and without a potential out-of-pocket cost. Responses were analyzed for associations with changes in attitudes if out-of-pocket costs were involved.
Results
Of 118 completed surveys, 68.2% of patients were aware of or had previously undergone TDM. Patient willingness to undergo TDM was high both with and without potential out-of-pocket costs (70 and 98%, respectively); however, patients were significantly less willing with out-of-pocket cost (p < 0.01). Higher disease-related quality of life scores, as measured by the short inflammatory bowel disease questionnaire (SIBDQ), was significantly associated with an increased willingness to assume a potential out-of-pocket cost (p = 0.007).
Conclusions
Overall, patients understand and are willing to undergo TDM in certain potentially beneficial clinical scenarios, however, are significantly less willing if paying out-of-pocket. A higher SIBDQ score was associated with an increase in willingness to undergo TDM when out-of-pocket cost was involved. Physicians should discuss TDM with their patients in order to make an informed and personalized treatment decision.
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Hydrogen-Rich Saline Ameliorates Hepatic Ischemia-Reperfusion Injury Through Regulation of Endoplasmic Reticulum Stress and Apoptosis
Abstract
Objective
To evaluate the effect of hydrogen-rich saline (HS) on hepatic ischemia-reperfusion (I/R) injury.
Methods
Forty rats were randomly allocated into five groups: one sham group (control group), one group treated with 20 min of ischemia and normal saline (NS; I/R1 + NS group), one group treated with 20 min of ischemia and HS (I/R1 + HS group), one group treated with 60 min of ischemia and NS (I/R2 + NS group), and one group treated with 60 min of ischemia and HS (I/R2 + HS group). After reperfusion for 6 h, hepatic function, oxidative stress, pathological changes, and apoptosis of hepatic cells were evaluated. Furthermore, the expression levels of endoplasmic reticulum (ER) stress-associated proteins were identified.
Results
Serum ALT and AST levels and tissue MDA content in the I/R + HS groups were significantly lower than those in the I/R + NS groups. Pathological changes were also significantly ameliorated in the HS groups compared with those in the NS groups. Moreover, HS appeared to significantly attenuate hepatic I/R-induced ER stress responses, as indicated by the decreased expression of C/EBP homologous protein, protein-kinase-RNA-like ER kinase, and inositol-requiring protein-1α, as well as the increased expression of GRP78 proteins. Finally, the levels of apoptotic markers such as caspase-3 and TUNEL-positive cells were significantly lower in the HS groups than in the NS control groups, whereas the level of Bcl2 protein increased in the HS groups.
Conclusion
The protective effect of HS can be attributed to ER stress and apoptosis inhibition.
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Clinical Features and Outcomes of Gastric Ischemia
Abstract
Background and Aims
Gastric ischemia is a rare condition associated with poor prognosis. Our study aim was to highlight the clinical features and outcomes of patients with gastric ischemia.
Methods
A retrospective review of patients diagnosed with isolated gastric ischemia at our institution from January 1, 2000, to May 5, 2016, was performed. Demographic, clinical, endoscopic, radiologic, and outcome variables were abstracted for analysis.
Results
Seventeen patients (65% men) with mean age of 69.3 ± 11.3 years and body mass index of 28.8 ± 11.1 were identified. The etiologies for gastric ischemia included local vascular causes (n = 8), systemic hypoperfusion (n = 4), and mechanical obstruction (n = 5). The most common presenting symptoms were abdominal pain (65%), gastrointestinal bleeding (47%), and altered mental status (23%). The typical endoscopic appearance was mucosal congestion and erythema with or without ulceration. Gastric pneumatosis and portal venous air were more commonly seen on CT imaging. Radiologic and/or surgical intervention was needed in 9 patients, while the remaining 8 patients were managed conservatively with acid suppression, antibiotics, and nasogastric tube decompression. The median duration of hospital stay was 15 days (range 1–36 days). There were no cases of rebleeding and the mortality rate as a direct result of gastric ischemia was 24% within 6 months of diagnosis.
Conclusion
Although uncommon, gastric ischemia is associated with significant mortality. Endoscopy and CT imaging play an important role in its diagnosis. The management of gastric ischemia is dictated by its severity and associated comorbidities.
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The Role and Regulation of the 11 Beta-Hydroxysteroid Dehydrogenase Enzyme System in Patients with Inflammatory Bowel Disease
Abstract
Introduction
Glucocorticoids are known to modulate a number of immunological responses including counteracting inflammation. Within tissues expressing the glucocorticoid and mineralocorticoid receptors including the colon, glucocorticoid metabolism is regulated by the isoenzymes of 11ß-hydroxysteroid dehydrogenase (11β-HSD). 11β-HSD1 acts as an oxidoreductase converting inactive cortisone into active cortisol, while 11β-HSD2 acts as a dehydrogenase converting active cortisol to inactive cortisone. Hexose-6 phosphate dehydrogenase (H6PDH) is a key regulator of 11β-HSD1 activity via its generation of NADPH. Variations in the 11β-HSD enzyme system in relation to levels of expression and regulation may have a role in IBD. The aim of this study was to investigate possible abnormalities of 11β-HSD enzyme system in the colon of patients with IBD.
Methods
By using quantitative real-time PCR, we investigated the transcription levels of 11β-HSD1 and 2 in colonic tissue from IBD patients and healthy controls undergoing a colonoscopy for disease assessment. Disease activity was recorded using clinical (Mayo Score/Harvey–Bradshaw Index), Biochemical (C-reactive protein), histological, and endoscopic parameters. In addition, transcription levels of H6PDH and the glucocorticoid receptor alpha (GR-α) as well as key pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, Rela (subunit for NF Kappa B)) were later examined among this group, and results were correlated with 11β-HSD2 gene expression. Results and patient demographics were expressed as a mean (and SD), and differences between IBD patients and control groups were analyzed using a Student's t test or Mann–Whitney U test as appropriate, with a p value of ≤0.05 considered significant. Results were controlled for disease activity as outlined above.
Results
Results have demonstrated a significant downregulation in 11β-HSD2 expression in IBD patients compared with controls (13.8 ± 17.1 au vs. 318.4 ± 521.1 au, p = 0.01), whereas levels of 11β-HSD1 did not appear to vary across the two groups. Among IBD patients, there was a trend toward higher 11β-HSD1 expression in inflamed tissue compared with matched non-inflamed tissue (422.1 ± 944 au vs. 102.2 ± 103.9, P = 0.09). Levels of H6PDH and the GR-α expression did not appear to vary among active inflamed IBD tissue and controls. As a result, we examined the association between pro-inflammatory cytokines and levels of 11β-HSD2 expression. Results showed an upregulation of key pro-inflammatory cytokine mRNA expression (TNF-α, IL-1β, IL-6) during inflammation with an associated downregulation of 11β-HSD2 mRNA expression when compared to controls. Dysregulation in this pathway could have a potential role in IBD pathogenesis and may account for exogenous glucocorticoid resistance in IBD. Further work assessing the role of the 11β-HSD enzyme system in steroid-resistant subjects is warranted.
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A Statistically Significant Association Between Esophageal Granular Cell Tumors and Eosinophilic Esophagitis: A 16-year Analysis at Two Large Hospitals of 167,434 EGDs
Abstract
Background
Esophageal granular cell tumor (eGCT) is a rare, usually benign, neoplasm of neuroectodermic origin. Eosinophilic esophagitis (EoE) is a relatively uncommon, immune-mediated, chronic disease. Both diseases commonly present with dysphagia. One case has been reported of simultaneous occurrence of both diseases.
Aims
To determine the association between diseases.
Methods
The present study was an IRB-approved, retrospective review of esophagogastroduodenoscopies (EGDs) with esophageal biopsies from two large hospitals, 1999–2014.
Results
Among 29,235 EGDs with esophageal biopsies for 16 years (167,434 total EGDs), 16 patients had pathologically diagnosed eGCT, and 1225 patients had pathologically diagnosed EoE. Five (31%) of 16 patients with eGCT had concomitant EoE (p = 0.001, OR 10.43, 95% ORCI 3.16–32.44, Fisher's exact test). Patients with simultaneous eGCT and EoE were young (mean age = 33.6 ± 12.9 years). Three were female. Dysphagia was presenting symptom in 4 (80%) of patients. Three had asthma. All five patients had > 20 eosinophils/hpf in esophageal biopsy specimens. Three patients had endoscopic esophageal abnormalities suggesting EoE. Four patients were treated with a PPI (before and after diagnosis of EoE), and 2 patients underwent six-food-elimination diet with partial symptomatic improvement. The eGCTs averaged 13.4 ± 4.2 mm in maximal diameter and were located in upper-2, middle-2, and lower esophagus-2 (1 patient had 2 eGCTs). eGCTs were endoscopically resected-3 patients, and monitored-2 patients. Surveillance endoscopies revealed no recurrence or growth of eGCTs after resection (mean follow-up = 4.6 years).
Conclusions
This novel report of 5 patients with simultaneous EoE and eGCT adds to one, previously published case and suggests these two diseases are associated, and have a common pathophysiologic link, despite apparently different pathogenesis. Large, prospective, endoscopic and pathologic studies are warranted to further investigate this association.
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Nonalcoholic Fatty Liver Disease Is Associated with Increased Risk of Reflux Esophagitis
Abstract
Background
Reflux esophagitis is associated with obesity and metabolic syndrome; however, the relationship between nonalcoholic fatty liver disease (NAFLD) and reflux esophagitis is unclear.
Aim
We examined the association between NAFLD and the development of reflux esophagitis.
Methods
Our cohort consisted of 117,377 Korean adults without reflux esophagitis at baseline who underwent a health checkup program including upper endoscopy between 2002 and 2014 and were followed annually or biennially until December 2014. NAFLD was defined as hepatic steatosis on ultrasonography in the absence of excessive alcohol use or any other identifiable cause.
Results
Over 520,843.2 person-years of follow-up, 22,500 participants developed reflux esophagitis (incidence density, 43.2 per 1000 person-years). In models adjusted for age and sex, the adjusted hazard ratio (aHR) (95% confidence interval [CI]) for incident reflux esophagitis in subjects with NAFLD compared to those without was 1.16 (1.13–1.20). After further adjustment for confounders of center, year of visit, smoking status, alcohol intake, regular exercise, education level, and body mass index, the association between NAFLD and incident reflux esophagitis was attenuated, but remained significant (aHR 1.06; 95% CI 1.02–1.10).
Conclusions
In this large cohort of Korean men and women, participants with NAFLD exhibited increased incidence of reflux esophagitis independent of possible confounders, suggesting that NAFLD contributes to the development of reflux esophagitis.
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Isolated Acute Terminal Ileitis Without Preexisting Inflammatory Bowel Disease Rarely Progresses to Crohn’s Disease
Abstract
Background
Isolated acute terminal ileitis without chronic features of inflammation poses a diagnostic challenge. Few studies have investigated the clinical significance of this entity in patients without history of inflammatory bowel disease.
Aims
We sought to elucidate the long-term prognosis of patients with isolated acute terminal ileitis, its rate of progression to Crohn's disease, and the factors associated with terminal ileitis development to Crohn's disease.
Methods
Retrospective review of clinical, endoscopic, and radiographic records was performed on 108 patients with histologic evidence of isolated acute terminal ileitis on terminal ileal biopsies obtained by diagnostic ileocolonoscopy performed between January 1, 2002, and December 31, 2014, at the Mayo Clinic. Statistical analysis was performed with Student's t test and Fisher's exact test to identify the factors associated with the progression of isolated acute terminal ileitis to Crohn's disease.
Results
The median follow-up time across 108 patients was 54.7 months (interquartile range 32.0–89.0 months). Five patients (4.6%) developed Crohn's disease after a median of 32.3 months (7.5–43.2 months). The presence of narrowing/stricturing (p = 0.03) on abdominal cross-sectional imaging at the time of terminal ileitis diagnosis was correlated with eventual Crohn's disease development. No significant correlation was found with clinical symptoms, endoscopic features, laboratory testing, NSAID use, smoking history, or family history of inflammatory bowel disease.
Conclusions
Isolated acute terminal ileitis discovered on diagnostic ileocolonoscopy rarely develops to Crohn's disease. Presence of stricturing/narrowing on cross-sectional imaging may predict eventual Crohn's disease development.
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Association of the Brain-Derived Neurotrophic Factor and Serotonin Transporter Genes with Parameters of the Early Components of Event-Related Potentials on Passive Word Perception
Associations of genes for the serotonin transporter (the 5-HTTLPR polymorphism) and the brain-derived neurotrophic factor (the BDNF Val66Met polymorphism) with the neurophysiological characteristics at the initial stage of processing lexical information in patients with schizophrenia spectrum disorder and human mental health were studied. Neurophysiological characteristics at the initial stage of processing meaningful verbal information were found to differ in carriers of different variants of the Val66Met and 5-HTTLPR polymorphisms. Word recognition efficiency in implicit conditions was greater in carriers of the ValVal (BDNF Val66Met) or SS (5-HTTLPR) polymorphisms than in carriers of the Met or L variants. Genetic variants were found to have significant effects in mentally healthy people but not in patients with schizophrenia disorders.
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Strengthening the Healthy Start Workforce: A Mixed-Methods Study to Understand the Roles of Community Health Workers in Healthy Start and Inform the Development of a Standardized Training Program
Abstract
Introduction Healthy Start (HS) is dedicated to preventing infant mortality, improving birth outcomes, and reducing disparities in maternal and infant health. In 2014, the HS program was reenvisioned and standardization of services and workforce development were prioritized. This study examined how HS community health workers (CHW), as critical members of the workforce, serve families and communities in order to inform the development of a CHW training program to advance program goals. Methods In 2015, an online organizational survey of all 100 HS programs was conducted. Ninety-three sites (93%) responded. Three discussion groups were subsequently conducted with HS CHWs (n = 21) and two discussion groups with HS CHW trainers/supervisors (n = 14). Results Most (91%) respondent HS programs employed CHWs. Survey respondents ranked health education (90%), assessing participant needs (85%), outreach/recruitment (85%), and connecting participants to services (85%) as the most central roles to the CHW's job. Survey findings indicated large variation in CHW training, both in the amount and content provided. Discussion group findings provided further examples of the knowledge and skills required by HS CHWs. Conclusions The study results, combined with a scan of existing competencies, led to a tailored set of competencies that serve as the foundation for a HS CHW training program. This training program has the capacity to advance strategic goals for HS by strengthening HS CHWs' capacity nationwide to respond to complex participant needs. Other maternal and child health programs may find these results of interest as they consider how CHWs could be used to strengthen service delivery.
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