Behavioural evidence on COVID-19 vaccine uptake.

OBJECTIVES: The World Health Organization has declared that COVID-19 is no longer a public health emergency of international concern. Nevertheless, it remains a public health issue, and seasonal vaccinations, at the same time of year as influenza vaccinations, will be necessary. When the first vaccines were administered in 2020, decision-makers had to make assumptions about the best methods to communicate and administer vaccines to increase uptake. Now, a body of evidence can inform these decisions. STUDY DESIGN: A narrative review written by three behavioural scientists who design research for policy. METHODS: We searched the PubMed database for: (i) reviews of interventions to increase uptake of COVID-19 or influenza vaccines and (ii) empirical studies on uptake of COVID-19 and influenza vaccines. In addition, registered trials gathered by a Cochrane scoping review of interventions to increase uptake of COVID-19 vaccines were searched for updated results. RESULTS: Results centre around two aspects of a vaccination campaign of interest to policymakers: communication and administration. Results suggest that communications highlighting the personal benefits of vaccination are likely to be more effective than those highlighting collective benefits. The efficacy of vaccination may be underestimated and stressing efficacy as a strong personal benefit may increase uptake. Keeping vaccines free, sending personalised messages, reminders and prebooked appointment times may also increase uptake. CONCLUSIONS: There is now a body of evidence from behavioural science that suggests how vaccination campaigns for COVID-19 can be structured to increase uptake. These recommendations may be useful to policymakers considering seasonal vaccination campaigns and to researchers generating hypotheses for country-specific trials.

Public misperceptions of COVID-19 vaccine effectiveness and waning: experimental evidence from Ireland.

OBJECTIVES: The study set out to measure public understanding of COVID-19 vaccine effectiveness (VE) and how effectiveness wanes with time since vaccination. Because perceived VE is a strong predictor of vaccine uptake, measuring perceptions can inform public health policy and communications. STUDY DESIGN: Online randomised experiment. METHODS: The study was undertaken in Ireland, which has high vaccination rates. A nationally representative sample (n = 2000) responded to a scenario designed to measure perceptions of COVID-19 VE against mortality. The length of time since vaccination in the scenario was randomly varied across four treatment arms (2 weeks, 3 months, 6 months, and 9 months). RESULTS: The public underestimates VE, with substantial variation in perceptions. A majority (57%) gave responses implying perceived VE against mortality of 0-85%, i.e., below scientific estimates. Among this group, mean perceived VE was just 49%. Over a quarter (26%) gave responses implying perceived VE greater than 95%, i.e., above scientific estimates. Comparing the four treatment groups, responses took no account of vaccine waning. Perceived VE was actually higher 9 months after vaccination than 2 weeks after vaccination. CONCLUSION: Despite high vaccination rates, most of the public in Ireland underestimates VE. Furthermore, the general public has not absorbed the concept of vaccine waning in the months following vaccination. Both misperceptions may reduce vaccine uptake, unless public health authorities act to correct them through improved communication.

A prospective clinical, cost and environmental analysis of a clinician-led virtual urology clinic.

INTRODUCTION: A virtual clinic is a form of telemedicine where contact between clinical teams and patients occur without face-to-face consultation. Our study aims to quantify the clinical, financial and environmental benefits of our virtual urology clinic. MATERIAL AND METHODS: We collected data prospectively from our weekly follow-up virtual clinic over a continuous four-month period between July and September 2017. RESULTS: In total, we reviewed 409 patients. Following virtual clinic consultation, 68.5% of our patients were discharged from further follow-up. The majority of our patients (male 57.7%, female 55.5%) were of working age. The satisfaction scores were high, at 90.1%, and there were no reported adverse events as a result of using the virtual clinic. Our calculated cost savings were £18,744, with a predicted 12-month cost saving of £56,232. The creation of additional face-to-face clinic capacity has created an estimated 12-month increase in tariff generation for our unit of £72,072. In total, 4623 travel miles were avoided by patients using the virtual clinic, with an estimated avoided carbon footprint of 0.35-1.45 metric tonnes of CO2e, depending on mode of transport. Our predicted 12-month avoided carbon footprint is 1.04-4.04 metric tonnes of CO2e. CONCLUSIONS: Our virtual clinic model has demonstrated a trifecta of positive outcomes, namely, clinical, financial and environmental benefits. The environmental importance and benefits of a virtual clinic should be promoted as a social enterprise value when engaging stakeholders in setting up such a urological service. We propose the adoption of our virtual clinic model in those urological units considering this method of telemedicine.

The effect of an attachment-oriented couple intervention for breast cancer patients and partners in the early treatment phase: A randomised controlled trial.

OBJECTIVE: Patients and partners both cope individually and as a dyad with challenges related to a breast cancer diagnosis. The objective of this study was to evaluate the effect of a psychological attachment-oriented couple intervention for breast cancer patients and partners in the early treatment phase. METHODS: A randomised controlled trial including 198 recently diagnosed breast cancer patients and their partners. Couples were randomised to the Hand in Hand (HiH) intervention in addition to usual care or to usual care only. Self-report assessments were conducted for both patients and partners at baseline, postintervention (5 months), and follow-up (10 months), assessing cancer-related distress, symptoms of anxiety and depression, and dyadic adjustment. Patients' cancer-related distress was the primary outcome. RESULTS: Cancer-related distress decreased over time in both patients and partners, but the intervention did not significantly affect this decrease at postintervention (P = .08) or follow-up (P = .71). A significant positive effect was found on dyadic adjustment at follow-up for both patients (P = .04) and partners (P = .02). CONCLUSIONS: There was no significant effect of the HiH intervention cancer-related distress. The results suggest that most couples can cope with cancer-related distress in the context of usual care. However, the positive effect on dyadic adjustment implies that the HiH intervention benefitted both patients and partners. Future studies should investigate how to integrate a couple focus in usual cancer care to improve dyadic coping in the early treatment phase.

An assessment of porcine dermal xenograft as an augmentation graft in the treatment of extensive rotator cuff tears.

Porcine dermal collagen (Zimmer Patch, formerly known as Permacol; Tissue Science Laboratories plc, Aldershot, Hampshire, UK) has been used for reinforcement of several human body tissues with success and has been shown to act as a durable, permanent tissue scaffold that assists healing. The purpose of this study was to determine the effectiveness of porcine dermal collagen as a tendon augmentation graft in the repair of extensive rotator cuff tears. This prospective study evaluated the clinical, ultrasound, and magnetic resonance imaging outcome 4.5 years (range, 3-5 years) after the treatment of extensive rotator cuff tears with porcine dermal collagen tendon augmentation grafting. The study group consisted of 10 patients (5 men, 5 women) with a mean age of 66 years (range, 46-80 years). Patients were evaluated clinically using the Constant score preoperatively, at 1 year, and at final follow-up when ultrasound and magnetic resonance imaging scans were performed to assess for graft and rotator cuff integrity. Average Constant scores improved from 41 preoperatively to 62 at final follow-up (P = .0003). Pain, abduction power, and range of motion significantly improved after surgery (P < .05), and patient satisfaction levels were high. Imaging studies identified intact grafts in 8 patients and graft detachment in 2. No adverse side effects were reported during the study period. The use of porcine dermal collagen as an augmentation graft in the treatment of massive rotator cuff tears is safe and, in most patients, is associated with improved clinical outcome. Randomized trials are required to assess any benefit over standard current surgical treatment regimens.

Immunostimulation and growth faltering in UK infants.

The purpose of the study was to determine whether chronic immunostimulation could explain growth faltering in disadvantaged children in the UK, as it does in developing countries such as The Gambia. In all, 216 infants, age 10-21 months, were recruited when blood samples were taken for the routine or clinical purposes of a longitudinal study tracking a larger cohort of children. Aliquots of blood were collected on Guthrie cards to determine blood concentrations of albumin (Alb), alpha(1)-antichymotrypsin (ACT), and immunoglobulin G (IgG). Haemoglobin concentrations were determined by routine hospital laboratory analysis. Heights and weights were measured and converted to z-scores; birth weights were used with recruitment weight to calculate a 'thrive index' for each child. Age-corrected plasma IgG concentration was negatively associated with both height- and weight-for-age z-scores (P = 0.042 and 0.038, respectively) but not with the thrive index or body mass index z-scores. Blood haemoglobin levels were positively related to height- and weight-for age z-scores, as well as to the thrive index (P = 0.026, 0.014, and 0.007, respectively). Although significant, these relationships could only account for a small part the observed growth variation. Although the relationships were weak, the results suggest that some of the observed variation in growth of these UK infants may be explained on the basis of persistent immunostimulation or poor iron status. In terms of markers of immunostimulation (Alb, ACT, ACT:Alb ratio, IgG), both absolute levels and relationships with height-for-age are substantially different than those previously observed in cohort studies of infants in The Gambia.

Efficacy of extended ceftiofur intramammary therapy for treatment of subclinical mastitis in lactating dairy cows.

Little research has focused on treatment of cows with subclinical mastitis during lactation. Ceftiofur is a new broad-spectrum, third-generation cephalosporin antibiotic for veterinary use that inhibits bacterial cell wall synthesis by interfering with enzymes essential for peptidoglycan synthesis. Ceftiofur should be effective against a wide range of contagious and environmental mastitis pathogens. Objectives of the present study were to evaluate the efficacy of ceftiofur for treatment of subclinical mastitis in lactating dairy cows, and to determine if extended therapy regimens enhanced efficacy of ceftiofur. Holstein and Jersey dairy cows (n = 88) from 3 dairy research herds were used. Cows were enrolled in the study based on milk somatic cell counts >400,000/mL and isolation of the same mastitis pathogen in 2 samples obtained 1 wk apart. Cows with one or more intramammary infections (IMI) were blocked by parity and DIM and allocated randomly to 1 of 3 different ceftiofur treatment regimens: 2-d (n = 49 IMI), 5-d (n = 41 IMI), and 8-d (n = 38 IMI) treatment regimens. For all groups, 125 mg of ceftiofur hydrochloride was administered via intramammary infusion. Eighteen cows with 38 IMI were included as an untreated negative control group. A bacteriological cure was defined as a treated infected mammary quarter that was bacteriologically negative for the presence of previously identified bacteria at 14 and 28 d after the last treatment. Efficacy of ceftiofur therapy against all subclinical IMI was 38.8, 53.7, and 65.8% for the 2-, 5-, and 8-d ceftiofur treatment regimens, respectively. Four of 38 (10.5%) IMI in control cows were cured spontaneously without treatment. All 3 ceftiofur treatment regimens were significantly better than the negative control, and the 8-d extended ceftiofur treatment regimen treatment group was significantly better than the standard 2-d treatment group. Pathogen groups had significantly different cure rates from one another. The cure rate for the 8-d extended ceftiofur treatment regimen was 70% for Corynebacterium bovis, 86% for coagulase-negative Staphylococcus species, 36% for Staph. aureus, 80% for Streptococcus dysgalactiae ssp. dysgalactiae, and 67% for Strep. uberis.

Early results of the Souter-Strathclyde unlinked total elbow arthroplasty in patients with osteoarthritis.

We have carried out a retrospective review of 11 Souter-Strathclyde primary total elbow arthroplasties in ten patients with osteoarthritis, over a period of nine years. The diagnosis was primary osteoarthritis in nine elbows and post-traumatic arthritis in two. The mean follow-up was 68 months (15 to 117). Although no patient was symptomatic, radiological review revealed evidence of loosening affecting three humeral and two ulnar components, one of which subsequently failed and was revised at 97 months. There were no dislocations, deep infections or mechanical failures. Complications included two superficial wound infections and two neurapraxias of the ulnar nerve which resolved. This study shows that the unlinked Souter-Strathclyde total elbow arthroplasty can be considered for patients with osteoarthritis and gives good symptomatic relief and improvement in function.

Growth faltering in rural Gambian infants is associated with impaired small intestinal barrier function, leading to endotoxemia and systemic inflammation.

Growth faltering of rural Gambian infants is associated with a chronic inflammatory enteropathy of the mucosa of the small intestine that may impair both digestive/absorptive and barrier functions. The aim of this study was to determine whether the enteropathy was associated with a compromised barrier function that allowed translocation of antigenic macromolecules from the gut lumen into the body, with subsequent systemic immunostimulation, resulting in growth retardation. Rural Gambian infants were studied longitudinally at regular intervals between 8 and 64 wk of age. On each study day, each child was medically examined, anthropometric measurements were made, a blood sample was taken and an intestinal permeability test performed. Evidence of chronic immunostimulation was provided by abnormally elevated white blood cell, lymphocyte and platelet counts, and frequently raised plasma concentration of C-reactive protein. Intestinal permeability was abnormal and associated with impaired growth (r = -0.41, P < 0.001). Plasma concentrations of endotoxin and immunoglobulin (Ig)G-endotoxin core antibody were also elevated and related to both growth (r = -0.30, P < 0.02; r = -0.64, P < 0.0001, respectively) and measures of mucosal enteropathy. Plasma IgG, IgA and IgM levels increased rapidly with age toward adult concentrations. Raised values were related to poor growth but also to measures of mucosal enteropathy and the endotoxin antibody titer. The interrelationships among these variables and growth suggested that they were all part of the same growth-retarding mechanism. These data are consistent with the hypothesis of translocation of immunogenic lumenal macromolecules across a compromised gut mucosa, leading to stimulation of systemic immune/inflammatory processes and subsequent growth impairment.

Elbow osteoarthritis: prognostic indicators in ulnohumeral debridement--the Outerbridge-Kashiwagi procedure.

A consecutive series of 43 patients (44 elbows) underwent ulnohumeral debridement for elbow osteoarthritis. Thirty-five patients (36 elbows) were reviewed after a mean follow-up of 39 months. Eighty-one percent of patients were satisfied, with 12 good, 19 fair, and 5 poor outcomes. The mean flexion/extension arc, pain score, and locking were all significantly improved, but a significant number of patients had rest pain. Patients who had symptoms for less than 2 years, considerable preoperative pain, or cubital tunnel syndrome had a significantly increased chance of a good outcome. The absence of preoperative locking was associated with a significantly increased chance of a poor outcome. A history of trauma, preoperative range of movement, and radiograph score did not predict outcome.

Elevated acute-phase protein in stunted Nepali children reporting low morbidity: different rural and urban profiles.

This study examined the associations between severity of stunting, plasma protein concentrations and morbidity of 104 Nepali boys, aged 10-14 years, living in contrasting environments. Boys from a remote village were compared with three similarly aged urban groups: poor squatters, homeless street children, and middle-class schoolchildren. All but the middle-class group were stunted, particularly village boys whose mean height-for-age z-score (-2.97, SD 0.82) indicates severe growth retardation. Stunting was significantly associated with increased plasma levels of the acute-phase protein alpha1-antichymotrypsin itself inversely related to plasma levels of albumin. Plasma ACT levels of village children (mean 1.52 g/l, SD 0.43) were three to four times higher than those of squatters and homeless street children, and five times higher than those of middle-class boys. Despite being the most severely stunted and having the most abnormal plasma protein values, village children reported the lowest burden of disease, a contradiction which may reflect exposure to sub-clinical infections or habituation to illness and low expectation of treatment. This study draws attention to the strikingly high levels of ACT and of stunting in the rural sample, and cautions on the use of uncorroborated morbidity reports across different epidemiological and socio-ecological environments. Possible mechanisms to explain the impact of illness and inflammation on growth faltering are discussed.

Anthelmintic treatment of rural Bangladeshi children: effect on host physiology, growth, and biochemical status.

BACKGROUND: The effect of helminth infestation on the nutrition, growth, and physiology of the host is still poorly understood. Anthelmintic treatment of children in developing countries has had varying success in terms of growth improvements. OBJECTIVE: The objective of this study was to assess the effect of regular deworming on child growth, physiology, and biochemical status. DESIGN: The study was a 12-mo longitudinal intervention in 123 Bangladeshi children aged 2-5 y. Treatment (mebendazole) or placebo tablets were administered every 2 mo for 8 mo and again at 12 mo. Weight, height, midupper arm circumference, intestinal permeability, plasma albumin, alpha(1)-antichymotrypsin, and total protein concentration were assessed every 2 mo. RESULTS: Treatment with mebendazole reduced the prevalence of Ascaris lumbricoides from 78% to 8%, of Trichuris trichiura from 65% to 9%, and of hookworm from 4% to 0%. There was no significant difference in the growth of treated children compared with those given placebo tablets. No changes in intestinal permeability or plasma albumin were observed after deworming. Significant decreases in total protein (P<0.001) and alpha(1)-antichymotrypsin (P<0.001) were observed in the treatment group, indicating possible reductions in inflammation and immunoglobulin concentration after deworming. A significant increase in the prevalence of Giardia intestinalis (from 4% to 49%) in the treatment group was associated with a short-term reduction in weight (P = 0.02) and higher intestinal permeability (P <0.001) in infected subjects. No long-term effects of G. intestinalis on growth were observed. CONCLUSION: Low-intensity helminth infections, predominantly of A. lumbricoides and T. trichiura, do not contribute significantly to the poor growth and biochemical status of rural Bangladeshi children.

Innate immunity, gut integrity, and vitamin A in Gambian and Indian infants.

Gut integrity, which can be measured by the urinary lactulose:mannitol excretion test, deteriorates with the introduction of weaning foods. In The Gambia, gut integrity measured monthly over 15 months in 119 infants (aged 2-15 months) was least impaired from April to June. This coincides with the time of year of maximum vitamin A (VA) intake-the mango season. Subsequently, two VA intervention studies were done in infants in India. Eighty infants attending a community health center received 16,700 IU weekly or placebo. In another study, 94 hospitalized infants were given 200, 000 IU VA or placebo: 31 received VA on admission, while the rest (32 VA, 31 placebo) received treatment on discharge. All VA-treated groups had more rapid improvement in gut integrity than the placebo groups, but no group had gut integrity normalized by Western standards. The data suggest that VA status may influence gut integrity.

The impact of infection and nutrition on gut function and growth in childhood.

Poor growth performance during infancy and early childhood is a frequent fact of life in most developing countries. Work in The Gambia has demonstrated that more than 43 % of observed growth faltering during the first 15 months of life can be explained by the presence of a mucosal enteropathy in the small intestine. Within communities the illness is very common: in the area investigated more than 95 % of infants above 8 months of age were affected, and on average they suffered a growth-limiting enteropathy for more than 75 % of their first year of life. Two mechanisms of weight loss have been defined. First, partial villus atrophy reduces absorption and digestion of lactose and probably other nutrients. Second, and more importantly, damage to the mucosal barrier allows translocation of macromolecules into the mucosa and blood, triggering both local and systemic immune and inflammatory mechanisms. Given the severity of the enteropathy it is not surprising that infants fail to grow at a normal rate. Recent findings suggest that these lesions continue throughout childhood and into adulthood. Thus, a persistence of chronic, local and systemic inflammation throughout childhood may be responsible for continued poor growth during this period. Although the nature of the enteropathy and the mechanisms of growth failure have been defined, the factors involved in the initiation and persistence of the intestinal lesion remain uncertain, making clinical management difficult. More work is clearly required to elucidate these factors and to define interventions to prevent or treat the enteropathy.

Giardia intestinalis is unlikely to be a major cause of the poor growth of rural Gambian infants.

Parasite-specific plasma immunoglobulins have been used to indicate the presence of Giardia intestinalis infection in 60 infants living in a rural area of The Gambia. Infants were studied longitudinally between 2 and 8 mo of age. The median age for first exposure to G. intestinalis was between 3 and 4 mo, and by 8 mo all but 3 infants (95%) showed a positive titer on at least one occasion. Raised Giardia-specific IgM titers were associated with reduced weight gain in the 2 wk preceding a positive titer, but catch-up growth occurred in the following 2 wk. IgM antibody titers were also positively associated with intestinal permeability (lactulose/mannitol ratio), urinary lactose excretion, plasma concentrations of alpha1-antichymotrypsin and total IgM, IgA and IgG immunoglobulins. However, infant growth over the whole 6-mo period (i.e., between 2 and 8 mo of age) was not related to mean Giardia-specific antibody titers, nor the time of first exposure to the parasite. The data suggest that giardiasis in these very young breast-fed children occurs as a mild, acute disease, and its presence could not explain the marked, long-term growth faltering observed in many of the subjects.

Glutamine oxidation and utilization by rat and human oesophagus and duodenum.

The rates of utilization and oxidation of glutamine and glucose by oesophageal and duodenal tissues have been investigated in both rats and human subjects. In the rat, glutamine utilization by oesophageal tissue was 2-3-fold lower than that in the duodenum, and this substrate contributed less than 10% to the total oxidative metabolism of the tissue, even when glutamine was the only substrate provided. In contrast, rat duodenal tissue derived about 34% of the total CO2 production from glutamine-C, and this contribution was not suppressed by the addition of either glucose or a mixture of the other substrates. Rates of glucose utilization and oxidation by the duodenum were lower than those for glutamine, and were significantly (P < 0.001) suppressed by addition of glutamine. In both oesophageal and duodenal tissues, less than 10% of the glutamine-C utilized was fully oxidized, approximately 60-70% was converted to glutamate, and 30-40% to alanine. Results obtained using human biopsy tissue samples were similar to those observed in the rat. Glutamine oxidation contributed 34 (SD 4)% of the total CO2 production by the duodenal tissue, but only 8 (SD 4)% to oesophageal tissue oxidation. The findings suggest that glutamine is not an important or preferred fuel for oesophageal tissue, whereas it is for duodenal tissue. Thus, these tissues can be expected to respond differently to glutamine administration.

Protein deficiency in a colony of western lowland gorillas (Gorilla g. gorilla)

A syndrome of alopecia and weight loss in a colony of 10 western lowland gorillas (Gorilla gorilla gorilla) in Gabon during a 3-yr period was apparently due to a dietary protein deficiency, with nine individuals affected to some extent. The most severely afflicted was a 4-yr-old female who eventually died as a result of acute gastroenteritis caused by Shigella flexneri. Clinical signs included chronic alopecia, hair discoloration, failure to thrive, and weight loss, and their severity was directly correlated with the degree of hypoalbuminemia (12 g/L in the most extreme case) and normocytic normochromic anemia. Preliminary clinical tests and autopsy results suggested a dietary protein or amino acid deficiency as the cause of the hypoalbuminemia, and further analyses of serum amino acid and protein levels were consistent with a diagnosis of dietary protein deficiency. Supplementation of the colony diet with a protein preparation for humans produced a rapid amelioration of signs and improvement in body and coat condition, a normalization of serum albumin and total protein levels, and disappearance of the anemia in all affected animals except a 12-yr-old male, who responded well to treatment with anabolic steroids. The natural diet of western lowland gorillas is surprisingly high in protein, and the dietary protein requirement of captive gorillas may be increased as a result of the absence of commensal gastrointestinal ciliates.

The treatment of selected fractures of the humeral shaft with the True-Flex nail.

The True-Flex nail was used in 23 selected non-pathological and eight pathological fractures/lesions of the humeral shaft. The overall fracture union rate was 69.5 per cent and the patients achieved a good range of movement of the shoulder and elbow. Nailing did not lead to union of established non-unions or fractures which were previously treated unsuccessfully by surgery despite bone grafting. All patients with pathological fractures/lesions regained good function of the arm and a good range of movement of the shoulder and the elbow. In one case the nail migrated proximally and impinged on the rotator cuff. This was revised. No other technical difficulties or complications were seen. The True-Flex nail is useful in the treatment of difficult and relatively recent humeral shaft fractures. Established non-unions or cases where previous surgery has failed should be treated by alternative methods.

Increase in skeletal muscle protein content by the beta-2 selective adrenergic agonist clenbuterol exacerbates hypoalbuminemia in rats fed a low-protein diet.

This investigation examined how the nutritional status of rats fed a low-protein diet was affected when the animals were treated with the beta-2 selective agonist clenbuterol (CL). Males (4 weeks old) from an inbred, specific-pathogen-free strain of hooded rats maintained at the Dunn Nutritional Laboratory were used in the experiments (N = 6 rats per group). CL treatment (Ventipulmin, Boehringer-Ingelheim Ltd., 3.2 mg/kg diet for 2 weeks) caused an exacerbation of the symptoms associated with protein deficiency in rats. Plasma albumin concentrations, already low in rats fed a low-protein diet (group A), were further reduced in CL rats (A = 25.05 +/- 0.31 vs CL = 23.64 +/- 0.30 g/l, P < 0.05). Total liver protein decreased below the level seen in either pair-fed animals (group P) or animals with free access to the low-protein diet (A = 736.56 +/- 26 vs CL = 535.41 +/- 54 mg, P < 0.05), whereas gastrocnemius muscle protein was higher than the values normally described for control (C) animals (C = 210.88 +/- 3.2 vs CL = 227.14 +/- 1.7 mg/g, P < 0.05). Clenbuterol-treated rats also showed a reduction in growth when compared to P rats (P = 3.2 +/- 1.1 vs CL = -10.2 +/- 1.9 g, P < 0.05). This was associated with a marked decrease in fat stores (P = 5.35 +/- 0.81 vs CL = 2.02 +/- 0.16 g, P < 0.05). Brown adipose tissue (BAT) cytochrome oxidase activity, although slightly lower than in P rats (P = 469.96 +/- 16.20 vs CL = 414.48 +/- 11.32 U/BAT x kg body weight, P < 0.05), was still much higher than in control rats (C = 159.55 +/- 11.54 vs CL = 414.48 +/- 11.32 U/BAT x kg body weight, P < 0.05). The present findings support the hypothesis that an increased muscle protein content due to clenbuterol stimulation worsened amino acid availability to the liver and further reduced albumin synthesis causing exacerbation of hypoalbuminemia in rats fed a low-protein diet.

Lowering of plasma triiodothyronine level and sympathetic activity does not alter hypoalbuminaemia in rats fed on a diet of low protein concentration.

Previous studies have described high plasma triiodothyronine (T3) concentrations and sympathetic activity in rats fed on low-protein diets. The present investigation examined how the nutritional status of rats fed on a low-protein diet was affected when these hormonal changes were reduced by drug administration. The low-protein diet (LP group) prevented growth, reduced plasma albumin levels, elevated plasma T3 concentration, and increased both the weight of the interscapular brown adipose tissue (BAT) and the activity of BAT cytochrome c oxidase (EC 1.9.3.1). Lowering the plasma T3 concentration (with carbimazole; CA group) elevated the plasma insulin concentration, promoted a small increase in the plasma albumin concentration and caused weight gain in comparison with the LP group. Reduction of sympathetic activity (with alpha-methyl-p-tyrosine; MT group) promoted a small elevation in plasma albumin concentration accompanied by a diminished T3 concentration, BAT weight, and an increase in fat deposition in relation to LP rats. In a second experiment, simultaneous lowering of the plasma T3 concentration and sympathetic activity (CA/MT group) resulted in weight gain associated with elevated plasma insulin concentration and fat deposition and a marked reduction in BAT cytochrome c oxidase activity. However no change in the hypoalbuminaemia was observed. The results of the present study suggest that in spite of the previously described increase in metabolic rate in fed on a diet with low-protein concentration when compared with controls, the mechanisms involved in the control of BAT activity and fat deposition seem to be independent of those which cause liver protein depletion and hypoalbuminaemia.