Online Communities for Child-Attracted Persons as Informal Mental Health Care: Exploring Self-Reported Wellbeing Outcomes.

Online support communities are gaining attention among child-attracted persons (CAPs). Though research has largely focused on the negative consequences these environments create for potential offending, they may also provide a beneficial alternative to more formal treatment settings. To assess the utility for clinical and therapeutic purposes, this analysis focused on subcultural dynamics to examine self-reported wellbeing outcomes of participation in a Dutch forum for CAPs. A total of 15 semi-structured interviews were conducted with moderators, members and mental health professionals involved in the community. Thematic analyses demonstrated that by means of informal social control, bonds of trust and social relational education, the network aims to regulate the behavior and enhance the wellbeing of its marginalized participants. Key outcomes include a decreased sense of loneliness and better coping with stigma, to the point that participants experience less suicidal thoughts. Association with prosocial peers also helps to set moral boundaries regarding behavior towards children, although we cannot fully rule out potential adverse influences. Online support networks offer a stepping stone to professional care that fits individual needs of CAPs, while also providing an informal environment that overcomes limitations of physical therapy and that extents principles of existing prevention and desistance approaches.

Parental home-based pulse oximetry monitoring for adults with intellectual disabilities at risk of serious respiratory problems including COVID-19: a brief report.

BACKGROUND: People with intellectual disabilities (ID) are at high risk of developing respiratory health issues. The COVID-19 pandemic has compounded this, with serious consequences, and for some, death. Despite home-based oxygen saturation monitoring being recommended for people with ID, there is a stark lack of evidence in the literature on its feasibility. METHOD: We conducted 3-day baseline home-based oxygen saturation monitoring, using pulse oximeters, with eight parents of nine adults with ID in Scotland. Two eligible parents also completed a further 2 weeks of monitoring, and returned an evaluation questionnaire on its feasibility. RESULTS: Baseline mean readings for eight adults with ID were within the normal range (%Sp02  ≥ 95), and for another one 94%. Fluctuations over the 3-day assessment period were experienced by six of these individuals. However, these variations were within limits which are not dangerous (lowest reading 92%), implying that parental home-based pulse oximetry monitoring is likely to be safe for adults with ID. The two parents who completed the evaluation found home-based pulse oximetry monitoring to be easy/very easy to do, and effective/very effective. CONCLUSIONS: This is the first research study, albeit with a very small sample, to report on the potential feasibility of parental home-based pulse oximetry monitoring for adults with ID. Home-based pulse oximetry monitoring appears to be safe in adults with ID at risk of developing serious respiratory problems, and not difficult for their parents to do. There is an urgent need to replicate this work, using a larger sample, to promote home-based respiratory health monitoring more widely for people with ID.

A randomized controlled clinical trial on the effect of acupuncture therapy in dairy cows affected by pyometra.

Pyometra (PYO) is a reproductive disease characterized by the accumulation of purulent or mucopurulent material within the uterine lumen, in the presence of an active corpus luteum (CL). As the CL continues secreting progesterone, PYO would develop following endometritis. Due to prohibited use of artificial luteolytic hormones in US certified organic dairies, conventional therapies consisting of administration of prostaglandin F2α, are not applicable. The objective of this study was to evaluate the efficacy of two acupuncture procedures on the treatment of persistent CL in cows with PYO. We hypothesized that acupuncture would reduce CL diameter and serum progesterone (P4) concentrations, leading to regression of PYO. Holstein cows with PYO, at an USDA certified organic dairy farm in Northern Colorado, were enrolled in a randomized controlled clinical trial and assigned to 1 of 3 treatments: (1) control pyometra (CP; no treatment; n = 17); (2) electroacupuncture (EAP; n = 15); and (3) laser acupuncture (LAP; n = 15). Each cow received three 9-min (EAP) or 20-min (LAP) acupuncture sessions in alternate days. All study cows had blood samples collected for determination of serum progesterone concentration at d0, and at d2, d4, d11, d18, and d25 after first treatment. The ovaries were scanned by transrectal ultrasonography at -3d, d0, d2, d4, d11, and d18 to determine the diameter of the CL. The effect of treatment in the outcome variables was evaluated by ANOVA and by repeated measures analyses, accounting for baseline data (CL diameter and progesterone serum concentration). Average ± SE change in CL diameter from d0 to d18 were 0.94 ± 1.0 mm, 0 ± 1.0 mm, and - 0.33 ± 1.0 mm for CP, EAP, and LAP, respectively. The repeated measures analysis indicated no significant differences for CL diameter among groups. None of the study cows had serum progesterone values <1 ng/ml by the end of the monitoring period (d25) and average ± SE change from d0 to d25 were - 4.0 ± 1.97 ng/ml, -0.76 ± 2.1 ng/ml, and 3.24 ± 1.9 ng/ml for CP, EAP, and LAP, respectively. The repeated measures analysis indicated no significant differences for serum progesterone concentrations among groups. On farm cow records reviewed 150 d after treatment indicated that 2 cows in EAP and 1 cow in LAP conceived 38 d, 68 d, and 38 d, after treatment completion. In conclusion, acupuncture was not an effective treatment for persistent CL in cows with PYO, during the monitoring period.

Dexamethasone for the prophylaxis of radiation-induced pain flare after palliative radiotherapy for symptomatic bone metastases: a phase II study.

AIMS: Pain flare occurs in over one-third of patients receiving palliative radiotherapy for bone metastases. A single dose of dexamethasone can decrease the incidence of pain flare during the first 2 days immediately after radiotherapy. We conducted a phase II prospective study to investigate the prophylactic role of prolonged dexamethasone. MATERIALS AND METHODS: Patients with bone metastases treated with a single 8Gy were prescribed 8mg dexamethasone just before palliative radiotherapy and for 3 consecutive days after treatment. Worst pain score and analgesic consumption data were collected at baseline and daily for 10 days after treatment. Analgesic consumption was converted into a total daily oral morphine equivalent dose in the analysis. Pain flare was defined (a priori) as a two-point increase in worst pain on an 11-point numeric rating scale compared with baseline with no decrease in analgesic intake, or a 25% increase in analgesic intake with no decrease in worst pain score. To distinguish pain flare from progressive disease, we required that the worst pain score and analgesic intake returned to baseline levels after the increase/flare. RESULTS: Forty-one patients were evaluable (32 men, nine women). Their median age was 67 years. The overall incidence of pain flare was 9/41 (22%) within 10 days after the completion of radiotherapy. Most (55%) of these pain flares occurred on day 5. Absence of pain flare was 34/41(83%) and 39/41 (95%) for days 1-5 and 6-10 after the completion of radiotherapy, respectively. CONCLUSION: Dexamethasone is effective in the prophylaxis of radiotherapy-induced pain flare after palliative radiotherapy for bone metastases. Randomised studies are needed to confirm this finding.

Minimally invasive techniques in colon surgery.

With the description of the first laparoscopic cholecystectomy in 1985, minimally invasive approaches have become the standard practice of surgeons in managing several disease processes. This has been mainly driven by the significant favorable impact of minimally invasive surgery on patient related outcomes. Smaller incisions lead to improved cosmesis, reduced postoperative pain and earlier return of gastrointestinal function. These factors in turn contribute to a faster recovery of the patient (compared to similar open procedures) with a reduced utilization of hospital resources, reduced costs and earlier return of the patient to normal routines of daily life and work. With experience it is clear that these favorable patient outcomes can also be seen with minimally invasive surgery for various colonic diseases and procedures. Many of the early concerns regarding minimally invasive approaches such as port site recurrence and the feasibility of adequate oncologic resections have been laid to rest by multiple randomized trials. There are now documented benefits to minimally invasive approaches for colonic diseases such as cancer, inflammatory bowel disease and diverticular disease; as long as surgeons choose the appropriate patients and spend the time and resources needed to become proficient at these advanced procedures.

Incidence and characteristics of juvenile tarsocrural osteochondrosis in purebred Angus bulls.

Osteochondrosis (OC) of the bovine tarsus has been suggested to contribute to osteoarthritis. The objective of this prospective cohort study was to provide data specific to the Angus breed. Clinical and radiographic exams evaluating OC lesions, effusion and osteoarthritis were performed in 50 purebred bull calves at three time points between 5.8 and 21 months of age. The likelihood of OC was lower at a median age of 12.4 months (P<0.001), primarily due to resolution of distal talus changes (P<0.01). Significant associations were observed between medial malleolus lesions and effusion at median age of 7.4 months (P<0.001). This study suggests that clinical and radiographic screening performed at approximately one year of age may be beneficial in detecting tarsal OC lesions in Angus breeding herds.

The effects of molybdenum water concentration on feedlot performance, tissue mineral concentrations, and carcass quality of feedlot steers,.

Thirty cross-bred steers (initial BW 452.0 ± 12.1 kg) were used to investigate the effects of Mo water concentration on performance, carcass characteristics, and mineral status of feedlot steers. The experimental design was a randomized complete block design. Steers were blocked by weight and then divided into 2 weight blocks each consisting of 15 steers. Steers were randomly assigned within block to one of 5 treatments (3 steers/treatment per block). Water treatments consisted of: 1) 0.0 µg/L, 2) 160 µg/L, 3) 320 µg/L, 4) 480 µg/L, and 5) 960 µg/L of supplemental Mo added as Na2MoO4 to the drinking water. Steers were housed in individual pens (steer = experimental unit) that contained individual 265 L water tanks for monitoring water intake. Steers were fed a growing diet for 28 d and then transitioned to a finishing diet. Block 1 steers were fed for a total of 151 d and block 2 steers were fed for a total of 112 d. Daily water intake was recorded for each steer. Steers were individually weighed on 2 consecutive days at the beginning and end of the experiment and interim weights and jugular blood samples were obtained every 28 d. Liver biopsies were obtained on d 0 and 84 from each steer within each block. Steers were transported to a commercial abattoir, slaughtered, and individual carcass data and liver samples were collected. Initial BW was used as a covariate for statistical analysis of data and significance was determined at P ≤ 0.05. No differences were observed for final BW (P > 0.98). Overall ADG (P > 0.91), DMI (P > 0.92), feed efficiency (P > 0.94), water intake (P > 0.40), hot carcass weight (P > 0.98), dressing percentage (P > 0.98), yield grade (P > 0.91), and marbling score (P > 0.29) did not differ across treatments. Lastly, no treatment differences were observed for liver concentrations of Cu (P > 0.93), Mo (P > 0.90) and Zn (P > 0.86) or plasma concentrations of Cu (P > 0.42), Mo (P > 0.43) and Zn (P > 0.62). These data indicate that water Mo concentration, within the range studied, had no impact on performance, mineral status, water intake, and carcass characteristics in feedlot steers.

Heritabilities and genetic correlations of pulmonary arterial pressure and performance traits in Angus cattle at high altitude.

Pulmonary arterial pressure (PAP) is an indicator trait for pulmonary hypertension and for the risk of developing high-altitude disease (HAD) in cattle. Pulmonary arterial pressures provide a tool for selection of breeding cattle for tolerance to high altitude in mountainous regions of the United States. The objective of this study was to evaluate relationships between growth performance traits and yearling PAP (42.4 ± 9.9 mmHg; = 5,776; elevation 2,150 m) using data from 1993 to 2014 in the John E. Rouse Colorado State University Beef Improvement Center (CSU-BIC) Angus herd. The breeding program used sires ( = 299) from both low- and high-elevation environments. We hypothesized that little to no genetic relationship exists between PAP and birth weight (BWT; direct and maternal), weaning weight (WW; direct and maternal), yearling weight (YW; direct and maternal), and postweaning gain (PWG). Historic selection of natural service sires from within the herd required a PAP of ≤ 42 mmHg. Outside AI sires ( = 156) used in this breeding program were not PAP tested and therefore were used with little knowledge of these sires' high-altitude adaptability. Performance traits (± SD) routinely recorded included BWT (36.2 ± 5.1 kg; = 8,695), WW (213.5 ± 31.8 kg; = 8,010), YW (345.6 ± 83.8 kg; = 5,580), and PWG (122.0 ± 63.7 kg; = 5,449), where PWG represented the total weight gained from weaning to yearling age. Four-trait analyses using REML were conducted with an animal model. The heritability estimates (± SE) for PAP (0.26 ± 0.03), BWT direct (0.42 ± 0.04) and maternal (0.14 ± 0.02), WW direct (0.29 ± 0.04) and maternal (0.19 ± 0.03), YW direct (0.45 ± 0.04) and maternal (0.23 ± 0.03), and PWG (0.14 ± 0.02) were in the range of those reported in previous literature. Estimates of genetic correlations (± SE) revealed weak relationships between PAP and direct and maternal BWT, direct and maternal WW, direct and maternal YW, and PWG of 0.15 ± 0.09, 0.14 ± 0.10, 0.23 ± 0.09, -0.01 ± 0.10, 0.12 ± 0.08, 0.00 ± 0.09, and -0.10 ± 0.10, respectively. The results of this study suggest that selection for lower PAP measures should have minimal influence on the growth performance of yearling Angus bulls and heifers at the CSU-BIC, supporting our hypothesis.

Static and dynamic components of right ventricular afterload are negatively associated with calf survival at high altitude.

The purposes of this study were to evaluate mean, systolic, and diastolic pulmonary arterial pressures; pulmonary arterial pulse pressures; and systemic oxygen extraction fraction as risk factors for the survival of suckling calves on one ranch located at an altitude of ≥ 2,730 m in Colorado, USA. A prospective cohort study of 58 calves was performed. Pulmonary arterial pressures and systemic oxygen extraction were measured when calves were approximately 3 mo (86 ± 7 d) and 7 mo (197 ± 6 d) of age. Seven of the 58 calves (12%), 4 steers and 3 heifers, were unaccounted for and presumed dead between 3 and 7 mo of age. Calves presumed to have died between 3 and 7 mo of age had significantly greater mean ( = 0.005) and systolic ( = 0.001) pulmonary arterial pressures and greater pulse pressures ( = 0.03) at 3 mo of age than calves that survived to 7 mo. Calves presumed to have died tended to have greater systemic oxygen extraction fractions at 3 mo of age than calves that survived ( = 0.13). Diastolic pressure was not associated with survival ( = 0.27). Mean pulmonary arterial pressure is predominantly determined by static resistance attributable to distal pulmonary arterial remodeling. Pulse pressure and systolic pulmonary arterial pressure represents the dynamic or oscillatory resistance and is determined by the characteristics of ventricular ejection and proximal arterial stiffness. These findings indicate that it may be beneficial to include pressure measurements indicative of both static and dynamic pulmonary arterial resistance in the selection of breeding stock at high altitude.

Angus calves born and raised at high altitude adapt to hypobaric hypoxia by increasing alveolar ventilation rate but not hematocrit.

The objective of this study was to evaluate the effect of altitude on arterial blood-gases and hematocrit in Angus-based calves. It was hypothesized that alveolar ventilation rate, as indicated by arterial pCO, would increase with altitude but hematocrit would not. Five Angus-based herds ( = 30 to 80 per cohort) located at 105 m, 1,470 m, 2,010 m, 2,170 m, and 2,730 m above sea level were enrolled in this prospective cohort study. A portable analyzer measured blood-gas tensions in coccygeal arterial blood. Calves at 1,470 m, 2,170 m, and 2,730 m were sampled twice, at approximately 4 mo and 7 mo of age. Calves at 105 m and 2,010 m were sampled once, at 7 or 4 mo of age, respectively. Linear regression analyses were used to determine the fixed effect of herd (a proxy for altitude) on the 4 outcome variables pCO, pO, pH, and hematocrit, while controlling for age and sex. As hypothesized, alveolar ventilation rate increased with altitude ( < 0.001). Hematocrit, however, did not show a clear association with altitude except for an increase from 105 m to ≥ 1,470 m ( < 0.001). Arterial pO decreased significantly with increasing altitude in calves at 4 mo and 7 mo of age ( < 0.001). The adjusted mean values of the 4 variables studied were similar at 4 and 7 mo of age for all of the herds studied. This indicates that suckling calves show minimal respiratory or erythrocytic adaptation to hypoxemia and hypocapnia with increasing age, regardless of altitude. We propose that the lack of an erythrocytic response in hypoxemic calves born and raised at high altitude prevents a deleterious increase in viscous resistance and, consequently, pulmonary arterial pressure. This physiological response, or lack thereof, may be a survival adaptation in a species predisposed to hypoxia-induced pulmonary hypertension.

Mean pulmonary arterial pressures in Angus steers increase from cow-calf to feedlot-finishing phases.

Pulmonary arterial hypertension due to hypoxia-induced pulmonary vascular remodeling is the predominant cause of right-sided congestive heart failure (CHF) in cattle. Historically, heart failure was problematic only at altitudes over 2,134 m. However, anecdotal reports suggest that the incidence of heart failure is increasing in feedlot cattle at moderate altitude (800 to 1,600 m), with late-fed, or fat, cattle at greatest risk. The goal of this study was to evaluate pulmonary arterial pressures (PAP) in a cohort of male Angus calves from suckling to finishing to better understand why heart failure is particularly problematic in fat cattle. It was hypothesized that mean PAP would increase through the feeding period and that the calves with the greatest pressures at high altitude would have the greatest pressures as fat cattle. A total of 362 PAP measurements were obtained from 153 calves. Calves were tested at altitudes of 2,170 (4 and 6 mo old), 1,560 (13 mo old), and 1,300 m (13 and 18 mo old). Mean PAP were greater in 18-mo-old steers than any other age group (mean = 50.3 mm Hg; 95% confidence interval 48.2 to 52.4; < 0.05). Calves that had the greatest mean pressure at 6 mo of age tended to have the greatest mean pressures at 18 mo of age ( = 0.45, < 0.001). The increase in mean PAP with increasing age and adiposity likely predisposed the steers to an increased risk of CHF during the finishing phase.

The altitude at which a calf is born and raised influences the rate at which mean pulmonary arterial pressure increases with age.

Right heart failure secondary to pulmonary hypertension is a leading cause of mortality among suckling beef calves in the Rocky Mountain region. The objective of this study was to track changes in pulmonary arterial pressures (PAP) in healthy calves born and raised at altitudes ranging from 1,470 to 2,730 m. It was hypothesized that calves located at higher altitudes would show a greater increase in mean PAP (mPAP) with age than would be experienced by calves located at lower altitudes. The rationale is that high altitude hypobaric hypoxia causes a greater rate of vascular remodeling and, consequently, greater resistance to blood flow than calves located at lower altitudes. A prospective study was conducted on 5 cohorts of suckling calves from 4 herds located at altitudes of 1,470, 2,010, 2,170, and 2,730 m. In total, 470 PAP measurements were obtained from 258 calves. As hypothesized, calves located at altitudes ≥2,170 m showed a significant increase in mPAP with age ( ≤ 0.002) whereas calves at 1,470 m did not ( = 0.16). Except for calves at 2,170 m ( < 0.001), systolic PAP did not increase with age ( ≥ 0.16). Diastolic PAP increased with age at altitudes ≥ 2,170 m ( ≤ 0.09) but did not change in calves at 1,470 m ( = 0.20). In summary, mPAP and the rate at which mPAP increases with age are positively associated with the altitude at which calves are born and raised.

Short-term nutritional supplementation during management of pulmonary exacerbations in cystic fibrosis: a controlled study, including effects of protein turnover.

Effects of nutritional supplements on minimizing weight loss and abnormalities of protein turnover during pulmonary exacerbations in cystic fibrosis (CF) were studied by controlled trial. Patients received pulmonary therapy and either standard diet (n = 10) or adjunctive enteral supplements (n = 12). Initial protein turnover, measured by [15N]glycine kinetics, showed alterations of protein synthesis (P Syn) and catabolism (P Cat), which correlated with the degree of underweight, and negligible net protein deposition (P Dep). With treatment both groups had significant increases in mean body weight and forced expiratory volume in 1 s, expressed as percent predicted value for height (FEV1) by 3 wk, but a significant correlation between initial underweight and subsequent weight gain was observed only in supplemented patients. Mean P Syn and P Dep increased significantly (p less than 0.001) only in the supplemented group. Pulmonary exacerbations in CF have important adverse effects on body-protein metabolism, similar to changes in protein-energy malnutrition and infection. These effects are reversed by short-term nutritional support. Strategic nutritional intervention should thus be considered in management, especially in malnourished patients.

Whole body protein turnover in malnourished cystic fibrosis patients and its relationship to pulmonary disease.

To investigate the effect of pulmonary disease in cystic fibrosis (CF), total body protein synthesis and catabolism were determined in eight CF children with acute exacerbations of pulmonary infection at the time of study (CF I), a group of CF children (n = 7) with chronic but stable pulmonary disease (CF II) and a group (n = 8) of healthy children. Protein synthesis was determined by the method of Waterlow et al (1978) using a single oral dose of 15N glycine and protein catabolism derived from nitrogen balance. Protein synthesis was markedly decreased (p less than 0.001) in the CF I group (1.01 +/- 0.10 g kg-1 10 h-1) compared with that of controls (2.02 +/- 0.08) and with CF children with chronic but stable pulmonary disease (CF II) (2.36 +/- 0.17). Protein catabolism was increased (p less than 0.01) in the CF II group compared with both controls and CF I. These findings contrast strongly to studies in normal children and those with mild protein-energy malnutrition (PEM) and infection, where infection increased protein synthesis, but are consistent with the observed decrease in protein turnover where severe PEM is accompanied by infection. We conclude that repeated pulmonary infection can adversely affect protein-energy balance and that adequate nutritional support should be considered in management during and after each episode.

The design and development of an integrated natural products screening database.

We designed and developed NEXUS--a new natural products screening database and related suite of software applications--to utilize the spectacular increases in assay capacity of the modern high throughput screening (HTS) environment. NEXUS not only supports seamless integration with separate HTS systems, but supports user-customized integration with external laboratory automation, particularly sample preparation systems. Designed and developed based on a detailed process model for natural products drug discovery, NEXUS comprises two integrated parts: (1) a single schema of Oracle tables and callable procedures and functions, and (2) software "front-ends" to the database developed using Microsoft Excel and Oracle Discovery/2000. Many of the back-end processing functions were written in Programming Language/Structured Query Language (PL/SQL) to provide an Application Programmer's Interface, which allows end users to create custom applications with little input from information technology professionals.

Efficacy of routine annual studies in the care of elderly patients.

The authors reviewed the results of annual laboratory screening (SMA 20, T3, T4, UA, EKG, chest x-ray) performed on a population of 500 institutionalized and ambulatory patients retrospectively followed from 1 to 19 years. With 30 laboratory values recorded for each annual exam, there were an average of 1.56 new abnormal laboratory findings per year per patient. A sample of 100 patients was further reviewed to determine the incidence of new diagnoses and treatment initiated by the appearance of new abnormal laboratory findings; 756 new abnormalities were recorded out of a possible 15,000, and 66 medical work-ups were initiated, which lead to new diagnoses in 21 cases and a treatment plan in 12 cases. The authors suggest that, in view of the rapid increase in the number of elderly persons and the consequent need to conserve limited health care resources, "standard" laboratory screening may not be warranted on a yearly basis in the elderly population.

Acute hemodynamic responses to weightlessness in humans.

As NASA designs space flights requiring prolonged periods of weightlessness for a broader segment of the population, it will be important to know the acute and sustained effects of weightlessness on the cardiovascular system since this information will contribute to understanding of the clinical pharmacology of drugs administered in space. Due to operational constraints on space flights, earliest effects of weightlessness have not been documented. We examined hemodynamic responses of humans to transitions from acceleration to weightlessness during parabolic flight on NASA's KC-135 aircraft. Impedance cardiography data were collected over four sets of 8-10 parabolas, with a brief rest period between sets. Each parabola included a period of 1.8 Gz, then approximately 20 seconds of weightlessness, and finally a period of 1.6 Gz; the cycle repeated almost immediately for the remainder of the set. Subjects were semi-supine (Shuttle launch posture) for the first set, then randomly supine, sitting and standing for each subsequent set. Transition to weightlessness while standing produced decreased heart rate, increased thoracic fluid content, and increased stroke index. Surprisingly, the onset of weightlessness in the semi-supine posture produced little evidence of a headward fluid shift. Heart rate, stroke index, and cardiac index are virtually unchanged after 20 seconds of weightlessness, and thoracic fluid content is slightly decreased. Semi-supine responses run counter to Shuttle crewmember reports of noticeable fluid shift after minutes to hours in orbit. Apparently, the headward fluid shift commences in the semi-supine posture before launch. is augmented by launch acceleration, but briefly interrupted immediately in orbit, then resumes and is completed over the next hours.

Multiple frequency bioelectrical impedance for the prediction of total body potassium in cystic fibrosis.

The use of multiple frequency bioelectrical impedance analysis (MFBIA) was compared with single frequency bioelectrical impedance analysis (SFBIA) and anthropometry to estimate the size of the body cell mass (BCM) in a paediatric cystic fibrosis population. BCM was independently determined from the accepted gold standard reference of total body potassium (TBK). MFBIA was used to measure the impedance of the body at 248 frequencies from 4 kHz to 1 MHz. Data were analysed using Cole-Cole plots of reactance versus resistance. The limits of agreement procedure was used to determine the reliability and precision of the different techniques to predict values for TBK, in an individual subject. The results indicate that MFBIA with a precision of 12% offers little improvement over single frequency BIA but is better and more accurate than anthropometry for the prediction of TBK in an individual patient.

Leucine metabolism and body cell mass in cystic fibrosis.

To further investigate the nature of malnutrition in cystic fibrosis (CF), specifically to evaluate the influence of body composition on leucine metabolism and determine whether measures used as reference standards alter comparative differences in protein metabolism, we measured [13C]leucine kinetics in nine well-nourished and eight malnourished, height-, FEV1-, and sex-matched CF subjects. Body cell mass was measured by total-body potassium (K40) analysis. Leucine turnover did not significantly differ between groups in absolute values or when corrected for body weight, body height, or surface area. However, malnourished CF patients had accelerated leucine turnover based on body cell mass measurements. Mean leucine synthesis per unit body cell mass in the malnourished group was 147% higher than that of the well-nourished group (p < 0.001). These data indicate that altered body composition is an important factor influencing protein metabolism in CF and should be considered in future metabolic studies. The importance of potentially serious but possibly correctable deficits in body cell mass in CF is emphasized.

Nutritional growth retardation is associated with defective lung growth in cystic fibrosis: a preventable determinant of progressive pulmonary dysfunction.

Evidence for a relationship between nutritional growth retardation in cystic fibrosis (CF) and progressive pulmonary dysfunction was evaluated by a prospective longitudinal study of changes in nutritional growth parameters, in relation to changes in pulmonary function data, in 61 moderately affected CF patients, aged 5-17 yr, during the equilibrated phase of lung growth. Age, sex, initial and serial weight and height Z scores, body cell mass (BCM) by total-body potassium (TBK) analysis, and changes in forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC), excluding data during pulmonary exacerbations, were analyzed by multiple regression analyses. The only significant predictor of change in FVC (best-fit model) was change in BCM, expressed as TBK (g/yr), TBK for age (percentage predicted), and TBK for height (percentage predicted) (p < 0.01). Standard anthropometric variables were not predictive. No reliable predictive model emerged for changes in FEV1. Relative decline in TBK for age was strongly predictive of decline in FVC (percentage predicted) accounting for 23% of this change. Patients with normal growth of the BCM had significantly less decline in FVC than those with retarded growth of the BCM (a fall of 2.5 vs. 6.8%/yr, p < 0.01). Impaired growth of the metabolically active BCM appears to be associated with progressive lung dysfunction in CF, possibly mediated by impaired lung growth. Achieving optimal nutrition and growth may minimize the progressive decline in pulmonary function commonly seen in this disease.