The altered gut microbiota in adults with cystic fibrosis.

BACKGROUND: Cystic Fibrosis (CF) is an autosomal recessive disease that affects the function of a number of organs, principally the lungs, but also the gastrointestinal tract. The manifestations of cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction in the gastrointestinal tract, as well as frequent antibiotic exposure, undoubtedly disrupts the gut microbiota. To analyse the effects of CF and its management on the microbiome, we compared the gut microbiota of 43 individuals with CF during a period of stability, to that of 69 non-CF controls using 454-pyrosequencing of the 16S rRNA gene. The impact of clinical parameters, including antibiotic therapy, on the results was also assessed. RESULTS: The CF-associated microbiome had reduced microbial diversity, an increase in Firmicutes and a reduction in Bacteroidetes compared to the non-CF controls. While the greatest number of differences in taxonomic abundances of the intestinal microbiota was observed between individuals with CF and the healthy controls, gut microbiota differences were also reported between people with CF when grouped by clinical parameters including % predicted FEV1 (measure of lung dysfunction) and the number of intravenous (IV) antibiotic courses in the previous 12 months. Notably, CF individuals presenting with severe lung dysfunction (% predicted FEV1 ≤ 40%) had significantly (p < 0.05) reduced gut microbiota diversity relative to those presenting with mild or moderate dysfunction. A significant negative correlation (-0.383, Simpson's Diversity Index) was also observed between the number of IV antibiotic courses and gut microbiota diversity. CONCLUSIONS: This is one of the largest single-centre studies on gut microbiota in stable adults with CF and demonstrates the significantly altered gut microbiota, including reduced microbial diversity seen in CF patients compared to healthy controls. The data show the impact that CF and it's management have on gut microbiota, presenting the opportunity to develop CF specific probiotics to minimise microbiota alterations.

Clostridium difficile carriage in adult cystic fibrosis (CF); implications for patients with CF and the potential for transmission of nosocomial infection.

Clostridium difficile is an anaerobic Gram-positive, spore-forming, toxin-producing bacillus transmitted among humans through the faecal-oral route. Despite increasing carriage rates and the presence of C. difficile toxin in stool, patients with CF rarely appear to develop typical manifestations of C. difficile infection (CDI). In this study, we examined the carriage, toxin production, ribotype distribution and antibiotic susceptibility of C. difficile in a cohort of 60 adult patients with CF who were pre-lung transplant. C. difficile was detected in 50% (30/60) of patients with CF by culturing for the bacteria. C. difficile toxin was detected in 63% (19/30) of C. difficile-positive stool samples. All toxin-positive stool samples contained toxigenic C. difficile strains harbouring toxin genes, tcdA and tcdB. Despite the presence of C. difficile and its toxin in patient stool, no acute gastrointestinal symptoms were reported. Ribotyping of C. difficile strains revealed 16 distinct ribotypes (RT), 11 of which are known to be disease-causing including the hyper-virulent RT078. Additionally, strains RT002, RT014, and RT015, which are common in non-CF nosocomial infection were described. All strains were susceptible to vancomycin, metronidazole, fusidic acid and rifampicin. No correlation was observed between carriage of C. difficile or any characteristics of isolated strains and any recorded clinical parameters or treatment received. We demonstrate a high prevalence of hypervirulent, toxigenic strains of C. difficile in asymptomatic patients with CF. This highlights the potential role of asymptomatic patients with CF in nosocomial transmission of C. difficile.

The effect of creatine monohydrate supplementation on sprint skating in ice-hockey players.

AIM: Creatine monohydrate supplementation is beneficial for enhancing high-intensity exercise performance, especially activities that involve repeated sprints. Creatine monohydrate supplementation is common in ice-hockey players. The purpose of this study was to determine the effect of creatine monohydrate supplementation on sprint skating performance in Junior B and collegiate ice-hockey players. METHODS: Seventeen ice-hockey players were randomly assigned to receive creatine (0.3 g/kg body mass/day for 5 days) or placebo. Before and after supplementation players performed repeated sprints to exhaustion on a skating treadmill (repeated 10-s sprints; 30-s rest between sprints) while blood lactate was simultaneously collected. The time to exhaustion on the treadmill test was calculated as total amount of time, including partial intervals, before the player reached exhaustion. Players were also tested for peak torque and average power during knee extension/flexion (3 sets of 10 reps; 60-s rest between sets) on an isokinetic dynamometer at 60 degrees/s. RESULTS: The change in time to exhaustion from before to after supplementation averaged 20.6+/-7 s in the creatine group and 21.9+/-13 s in the placebo group, with no differences between groups. Likewise, there were no differences between groups for changes in isokinetic peak torque and average power. There were no differences between groups over time for blood lactate changes during the repeated sprints on the treadmill. CONCLUSIONS: We conclude that creatine was not effective for improving performance in these ice-hockey players.

Creatine monohydrate and resistance training increase bone mineral content and density in older men.

Our purpose was to determine the effects of creatine supplementation combined with resistance training on bone mineral content and density in older men. Twenty-nine older men (age 71 y) were randomized (double blind) to receive creatine (0.3 g/kg creatine for 5 d and 0.07 g/kg thereafter) or placebo while participating in resistance training (12 weeks). Bone mineral content and density were determined by dual energy X-ray absorptiometry before and after training. There was a time main effect for whole-body and leg bone mineral density (p < or = 0.05) with these measures increasing by approximately 0.5%, and 1%, respectively in the combined groups. There was a group by time interaction for arms bone mineral content, with the group receiving creatine increasing by 3.2% (p < 0.01) and the group receiving placebo decreasing by 1.0% (not significant). Changes in lean tissue mass of the arms correlated with changes in bone mineral content of the arms (r = 0.67; p < 0.01). Resistance training of 12 weeks increases bone mineral density in older men and creatine supplementation may provide an additional benefit for increasing regional bone mineral content. The increase in bone mineral content may be due to an enhanced muscle mass with creatine, with potentially greater tension on bone at sites of muscle attachment.

Creatine supplementation combined with resistance training in older men.

PURPOSE: To study the effect of creatine (Cr) supplementation combined with resistance training on muscular performance and body composition in older men. METHODS: Thirty men were randomized to receive creatine supplementation (CRE, N = 16, age = 70.4 +/- 1.6 yr) or placebo (PLA, N = 14, age = 71.1 +/- 1.8 yr), using a double blind procedure. Cr supplementation consisted of 0.3-g Cr.kg(-1) body weight for the first 5 d (loading phase) and 0.07-g Cr.kg(-1) body weight thereafter. Both groups participated in resistance training (36 sessions, 3 times per week, 3 sets of 10 repetitions, 12 exercises). Muscular strength was assessed by 1-repetition maximum (1-RM) for leg press (LP), knee extension (KE), and bench press (BP). Muscular endurance was assessed by the maximum number of repetitions over 3 sets (separated by 1-min rest intervals) at an intensity corresponding to 70% baseline 1-RM for BP and 80% baseline 1-RM for the KE and LP. Average power (AP) was assessed using a Biodex isokinetic knee extension/flexion exercise (3 sets of 10 repetitions at 60 degrees.s(-1) separated by 1-min rest). Lean tissue (LTM) and fat mass were assessed using dual energy x-ray absorptiometry. RESULTS: Compared with PLA, the CRE group had significantly greater increases in LTM (CRE, +3.3 kg; PLA, +1.3 kg), LP 1-RM (CRE, +50.1 kg; PLA +31.3 kg), KE 1-RM (CRE, +14.9 kg; PLA, +10.7 kg), LP endurance (CRE, +47 reps; PLA, +32 reps), KE endurance (CRE, +21 reps; PLA +14 reps), and AP (CRE, +26.7 W; PLA, +18 W). Changes in fat mass, fat percentage, BP 1-RM, and BP endurance were similar between groups. CONCLUSION: Creatine supplementation, when combined with resistance training, increases lean tissue mass and improves leg strength, endurance, and average power in men of mean age 70 yr.

The effect of 7 days of creatine supplementation on 24-hour urinary creatine excretion.

Since the discovery that oral ingestion of creatine leads to an increase in intramuscular creatine, its supplementation has become widespread. However, the dosage necessary to maximize retention and create significant increases in intramuscular creatine is poorly understood. In this study, 24-hour urinary creatine and creatinine levels of 20 university men's football players and 20 university men's hockey players involved in a resistance-exercise program and supplementing with creatine were collected and analyzed. In a double-blind, randomized design, 10 football players and 10 hockey players were randomly assigned to either the supplement or placebo group. Subjects provided a 24-hour urine sample twice during the study: once prior to supplementation (baseline) and the second 7 days after daily supplementation and resistance exercise. Creatine dosage was 0.1 g x kg(-1) lean body mass. The quantity of creatine ingested was compared with the amount excreted in the urine of those subjects supplementing with creatine and with placebo. Creatinine levels were compared between the first and second urine collection and between groups. Creatine and creatinine concentrations were determined using high-performance liquid chromatography. In 24-hours, 46% of the ingested creatine was excreted. There was no change in creatine levels for placebo subjects. Creatinine levels remained the same within groups at the first and second collection times (p < 0.05). Our findings indicate that when supplementing with dosages of 0.1 g x kg(-1) lean body mass or between 6 and 8 g at a time, approximately half of the ingested creatine gets excreted. Because there was no change in urinary creatinine, it can be assumed that enhanced degradation of creatine did not occur.

The effect of whey protein supplementation with and without creatine monohydrate combined with resistance training on lean tissue mass and muscle strength.

Our purpose was to assess muscular adaptations during 6 weeks of resistance training in 36 males randomly assigned to supplementation with whey protein (W; 1.2 g/kg/day), whey protein and creatine monohydrate (WC; 0.1 g/kg/day), or placebo (P; 1.2 g/kg/day maltodextrin). Measures included lean tissue mass by dual energy x-ray absorptiometry, bench press and squat strength (1-repetition maximum), and knee extension/flexion peak torque. Lean tissue mass increased to a greater extent with training in WC compared to the other groups, and in the W compared to the P group (p < .05). Bench press strength increased to a greater extent for WC compared to W and P (p < .05). Knee extension peak torque increased with training for WC and W (p < .05), but not for P. All other measures increased to a similar extent across groups. Continued training without supplementation for an additional 6 weeks resulted in maintenance of strength and lean tissue mass in all groups. Males that supplemented with whey protein while resistance training demonstrated greater improvement in knee extension peak torque and lean tissue mass than males engaged in training alone. Males that supplemented with a combination of whey protein and creatine had greater increases in lean tissue mass and bench press than those who supplemented with only whey protein or placebo. However, not all strength measures were improved with supplementation, since subjects who supplemented with creatine and/or whey protein had similar increases in squat strength and knee flexion peak torque compared to subjects who received placebo.

Effect of glutamine supplementation combined with resistance training in young adults.

The purpose of this study was to assess the effect of oral glutamine supplementation combined with resistance training in young adults. A group of 31 subjects, aged 18-24 years, were randomly allocated to groups (double blind) to receive either glutamine (0.9 g x kg lean tissue mass(-1) x day(-1); n = 17) or a placebo (0.9 g maltodextrin x kg lean tissue mass(-1) x day(-1); n = 14 during 6 weeks of total body resistance training. Exercises were performed for four to five sets of 6-12 repetitions at intensities ranging from 60% to 90% 1 repetition maximum (1 RM). Before and after training, measurements were taken of 1 RM squat and bench press strength, peak knee extension torque (using an isokinetic dynamometer), lean tissue mass (dual energy X-ray absorptiometry) and muscle protein degradation (urinary 3-methylhistidine by high performance liquid chromatography). Repeated measures ANOVA showed that strength, torque, lean tissue mass and 3-methylhistidine increased with training (P < 0.05), with no significant difference between groups. Both groups increased their 1 RM squat by approximately 30% and 1 RM bench press by approximately 14%. The glutamine group showed increases of 6% for knee extension torque, 2% for lean tissue mass and 41% for urinary levels of 3-methylhistidine. The placebo group increased knee extension torque by 5%, lean tissue mass by 1.7% and 3-methylhistidine by 56%. We conclude that glutamine supplementation during resistance training has no significant effect on muscle performance, body composition or muscle protein degradation in young healthy adults.

The effect of continuous low dose creatine supplementation on force, power, and total work.

Dietary supplementation (SUP) has become a significant part of athletic training. Studies indicate that creatine (Cr) can enhance short-duration, high-intensity activities. This study examined the effect of 21 days of low dose Cr SUP ( approximately 7.7 g/day) and resistance training on force output, power output, duration of mean peak power output, and total work performed until fatigue. A double-blind protocol was used, where an individual, who was not part of any other aspect of the study, randomly assigned subjects to creatine and placebo groups. Forty-one male university athletes were randomly assigned to either Cr (n = 20) or placebo (n = 21) SUP. On the first and last day of the study, subjects were required to perform concentric bench press movements until exhaustion on an isokinetic dynamometer. The dynamometer was hard-wired to a personal computer, which provided force, velocity, and duration measures. Force and power output until fatigue, were used to determine total work, force-time, and power-time relationships. ANOVA results revealed that the Cr subjects performed more total work until fatigue, experienced significantly greater improvements in peak force and peak power, and maintained elevated mean peak power for a longer period of time. These results indicate that Cr SUP can significantly improve factors associated with short-duration, high-intensity activity.

Analysis of creatine and creatinine in urine by capillary electrophoresis.

Creatine is found in the urine of subjects ingesting creatine monohydrate as an ergogenic aid. Creatinine, the catabolic breakdown product of creatine, is a major constituent of normal urine. It is of interest to follow the excretion of creatine and creatinine in urine as a function of time after creatine ingestion. In this study, creatine and creatinine were analyzed in urine by capillary electrophoresis. The optimization of the method was discussed, with the best results being obtained using a 30 mM phosphate-150 mM sodium dodecyl sulfate buffer at pH 6, with the detector set at 214 nm and an applied voltage of 15 kV across a 45 cm capillary. Verification of the method was provided by HPLC analysis and spiking. The application of the method was demonstrated by analysis of creatine and creatinine in urine samples collected in a 24-h period following creatine ingestion.

The utility of clinical and radiographic features in the diagnosis of cytomegalovirus central nervous system disease in AIDS patients.

BACKGROUND: Polymerase chain reaction (PCR) assays of cerebrospinal fluid (CSF) for cytomegalovirus (CMV) DNA have facilitated the diagnosis of CMV-associated central nervous system disease in AIDS patients. We attempt to correlate clinical and radiographic features that are associated with CMV PCR- positivity in CSF from AIDS patients with neurologic disease. METHODS AND RESULTS: A retrospective case controlled comparison was made of CMV PCR-positive and PCR-negative patients. RESULTS: CMV PCR-positive patients were significantly more likely to have nystagmus, prior CMV retinitis, and CSF protein levels.90 mg/dL. Of patients with 0, 1, and $2 of these features, 5.6%, 55.2%, and 88.9%, respectively, were PCR-positive. Ependymal enhancement was present by magnetic resonance imaging in 9 of 12 PCR-positive, and in 8 of 30 PCR-negative patients. CONCLUSION: These clinical and radiographic features may serve as useful adjuncts toward the establishment of the diagnosis of CMV-associated neurologic disease in AIDS patients.

Modifications to the Standard Sit-and-Reach Flexibility Protocol.

OBJECTIVE: To present several modifications of the standard sit-and-reach protocol. BACKGROUND: Many exercises designed to increase strength and aerobic capacity tend to decrease the flexibility of the erector spinae and hamstrings musculature. Less-than-ideal flexibility in these soft tissues may increase the risk of injury during training, competition, or activities of daily living. The most widely used measures of flexibility have been either the stand-and-reach or the sit-and-reach, but both are limited to a single measure. DESCRIPTION: Using the new multitest flexometer, we were able to take 6 flexibility measures beyond the stand-and-reach test: standard active sit-and-reach, standard passive sit-and-reach, modified active sit-and-reach with external rotators slackened, modified passive sit-and-reach with external rotators slackened, modified active sit-and-reach with the hamstrings, gastrocnemii, and external rotators slackened, and modified passive sit-and-reach with the hamstrings, gastrocnemii, and external rotators slackened. CLINICAL ADVANTAGES: This modified sit-and-reach protocol allows the indirect assessment of the influence of the 4 major muscle groups that affect sit-and-reach scores: erector spinae, hip rotators, hamstrings, and gastrocnemii.

Polymerase chain reaction detection and clinical significance of varicella-zoster virus in cerebrospinal fluid from human immunodeficiency virus-infected patients.

Varicella-zoster virus (VZV) causes ocular and other central nervous system (CNS) disease in human immunodeficiency virus (HIV)-infected persons. To study the prevalence of CNS disease due to VZV, cerebrospinal fluid (CSF) specimens from 84 consecutive HIV-infected patients with new neurologic symptoms were tested for VZV DNA by a polymerase chain reaction (PCR) assay. Six patients were PCR-positive for VZV in CSF; 3 additional patients were subsequently identified who were not part of the serial population sample. Among these 9 patients, all had clinical presentations consistent with ocular and other CNS disease due to VZV; 4 were without zoster on presentation. Sustained improvement in association with antiviral therapy was observed in 3. Therefore, VZV DNA was detected in the CSF of 7% of HIV-infected patients presenting with neurologic symptoms; the diagnosis of VZV-related CNS disease was facilitated by this assay; improvement in association with antiviral therapy was observed in some patients.

Histoplasmosis and kidney disease in patients with AIDS.

Renal disease in patients infected with human immunodeficiency virus (HIV) often presents with significant proteinuria and progressive renal failure; focal glomerulosclerosis is the most common renal pathology identified. To our knowledge, we report the first case of nephrotic-range proteinuria and preserved renal function in an HIV-infected patient in association with disseminated histoplasmosis. The initial level of proteinuria was 12.5 g/24 h. The patient developed a concomitant lesion on his neck, which was biopsied and identified as Histoplasma capsulatum by fungal stains and culture. The serum CF titer of antibody against yeast antigens of H. capsulatum was 1:8. The level of serum albumin decreased to 2.0 g/dL, and the level of serum cholesterol increased to 284 mg/dL. Immunohistochemical staining of renal biopsy tissue demonstrated immune complexes within the mesangium; H. capsulatum antigen was also demonstrated in the mesangium. Therapy with oral itraconazole resulted in marked clinical improvement. The findings in this case emphasize the need to rule out treatable causes of the nephrotic syndrome in AIDS, especially in cases of immune-complex glomerulonephritis.

Determination of fluoroacetate in biological matrixes as the dodecyl ester.

A new method for the quantitative determination of fluoroacetate in biological samples was applied to a number of avian samples. Fluoroacetate is isolated as its potassium salt by ion-exchange chromatography and directly converted to its dodecyl ester, using a novel derivatization procedure. The ester is quantified by capillary gas chromatography with a flame ionization detector for the range 1.0-10.0 micrograms/g and by selected ion monitoring GC/mass spectrometry for the range 0.01-1.00 microgram/g. Recoveries from 1 g chicken muscle were about 80%. The method was applied to the determination of fluoroacetate in the crop, stomach, liver, heart, intestine, and breast muscle of 5 Zebra finches (Peophila guttata) that had been fed millet containing 9 micrograms/g of sodium fluoroacetate. Despite a wide variation in dose, the levels in organs and tissues were approximately 1 microgram/g except for heart tissue which was about 2 micrograms/g. The presence of interfering peaks at low levels necessitated the use of selected ion monitoring GC/MS when sample weights were less than 1 g or when levels were less than 1 microgram/g. Samples can be analyzed within hours of receipt; therefore, the method is suitable for routine use in a diagnostic laboratory.

Determination of organic acids in seven wheat varieties by capillary gas chromatography.

Fresh wheat tops were extracted with acidic 90% ethanol, and the ethanol was evaporated and a portion of the aqueous residue loaded onto DEAE-Sephadex. Organic acids were eluted with pyridinium formate and then lyophilized and the dried residue was derivatized with 1% trimethylchlorosilane in bis(trimethylsilyl)trifluoroacetamide. The acids were then quantitatively determined using capillary gas chromatography and identified using capillary gas chromatography-mass spectrometry. The acidic ethanol extraction of fresh plant tissue was quantitative for all acids except citric while losses in the remaining procedures were controlled by using an internal standard. The ion exchange chromatography made the greatest contribution to experimental error, imposing a minimum loading requirement of 0.1 mumol of each acid for adequate precision. Organic acid profiles were determined for seven wheat cultivars (Triticum aestivum cv Carazinho, Teal, Lance, Warigal, Isis, Maringa, and BH1146) grown on gravel in solution culture for 30 days. Profiles were simple, consisting of only malic, aconitic, and citric acids, with levels of each acid for all varieties falling within the range 2-5 mumol/g fresh tissue. Storage of samples led to a large increase in sampling error and increased the amount of extractable citric acid.

Profiles of urinary volatiles from metabolic disorders characterized by unusual odors.

The profiles of urinary volatiles from patients with phenylketonuria, maple syrup urine disease, isovaleric acidemia, or trimethylaminuria (fish-odor syndrome) were in each case vastly different from the normal urinary volatiles profile. In the maple syrup urine disease case, metabolites that occur distal to the block were found and a mechanism for their formation is suggested. A new major metabolite in isovaleric acidemia was also found. As well as providing a reliable diagnostic tool for diseases characterized by odors, the analysis of urinary volatiles may provide information to help our understanding of still unexplained aspects of the diseases.