Short- and medium-term prognosis of HIV-infected patients receiving intensive care: a Brazilian multicentre prospective cohort study.

OBJECTIVES: The characteristics of critically ill HIV-positive patients and the causes of their admission to intensive care units (ICUs) are only known through retrospective and unicentric studies. This study aims to fill this knowledge gap. METHODS: This is a prospective, multicentre cohort study of short- and medium-term prognostic factors. The setting consisted of ICUs of three tertiary referral hospitals from the three largest metropolitan areas in Brazil in the period January 2014 to November 2015. In all, 161 HIV patients over 18 years old were included. RESULTS: The clinical data of the outcomes (ICU mortality, hospital mortality and 90-day survival) were extracted from medical records using the REDCap®ï¸ web-based form and analysed with the MedCalc®ï¸ application. Median age was 41.7 [interquartile range (IQR): 34-50] years, the Simplified Acute Physiologic Score 3 (SAPS 3) was 64 (IQR: 56-74), and the Sequential Organ Failure Assessment Score (SOFA) was 6 (IQR: 4-9) points. The main causes of admission were sepsis (54.5%) and acute respiratory failure (13.7%). ICU and hospital mortality rates were 32.3% and 40.4%, respectively. In a multivariate analysis, time until ICU admission ≥ 3 days (P = 0.0013), performance status (Eastern Cooperative Oncology Group score, P = 0.0344), coma (Glasgow Coma Scale ≤ 8 points, P = 0.0213) and sepsis (P = 0.0003) were associated with increased hospital mortality. Coma (P = 0.0002) and sepsis (P = 0.0008) were independently associated with 90-day survival. CONCLUSIONS: Delayed ICU admission and the severity of critical illness determine the short- and medium-term mortality rates of HIV-infected patients admitted to the ICU, rather than factors associated with HIV infection. These results suggest that prognostic factors of HIV-infected patients in the ICU are similar to those of non-HIV-infected populations.

Infecção latente pelo herpesvírus bovino tipo 1 em búfalos (Bubalus bubalis) no Rio Grande do Sul / Bovine herpesvirus type 1 latent infection in buffalo (Bubalus bubalis) in Rio Grande do Sul

Apesar dos bovinos serem considerados os hospedeiros naturais do BoHV-1, estudos sorológicos têm sugerido que búfalos podem ser suscetíveis ao BoHV-1 e a outros alfa-herpesvírus geneticamente relacionados. O objetivo deste estudo foi detectar a presença de DNA viral de BoHV-1 em 202 amostras de gânglios trigêmeos de búfalos, pela técnica de semi-nested PCR, para detecção de um segmento do gene codificante da glicoproteína D (gD) do BoHV-1. Além disso, 242 amostras de soro foram analisadas pela técnica de soroneutralização (SN) para a detecção de anticorpos neutralizantes contra BoHV-1, BoHV-5 e BuHV. Todas as amostras clínicas foram coletadas em um matadouro na cidade de Pelotas, RS, Brasil. O DNA de BoHV-1 foi detectado em 61 (30,1%) gânglios, e os resultados da SN demonstraram que 27,6% dos animais apresentaram anticorpos contra, pelo menos, um dos vírus testados. O sequenciamento genômico e a análise de 14 amplicons confirmaram a presença do DNA do BoHV-1 nos tecidos analisados. Em resumo, os resultados indicam que o BoHV-1 está distribuído em rebanhos bubalinos provenientes da região Sul do Brasil. Entretanto, são necessárias investigações adicionais, no sentido de elucidar o papel exato dos búfalos na epidemiologia das infecções pelo BoHV-1.(AU)

Although bovines are natural hosts for BoHV-1, serologic studies in several countries have suggested that buffaloes (Bubalus bubalis) may be susceptible to BoHV-1 and other genetically related alphaherpesvirus. This study aimed to investigate the presence of BoHV-1 DNA in trigeminal ganglia from 202 buffaloes by a semi-nested PCR to amplify partially the glycoprotein D (gD) gene of BoHV-1. Additionally, 242 serum samples were tested by serum neutralization (SN) for the detection of antibodies against BoHV-1, BoHV-5 and BuHV. All clinical samples were collected in a slaughterhouse located in Pelotas, RS, Brazil. BoHV-1 DNA was detected in 61 (30.1%) of the samples and SN revealed 27.6% of the animals with neutralizing antibodies against at least one of the tested viruses. Nucleotide sequencing of 15 amplicons followed by BLAST analysis confirmed the presence of BoHV-1 DNA in the analyzed tissues. Taken together, these data indicate that BoHV-1 infection is distributed in buffaloes in southern Brazil. However, the role of buffaloes in the BoHV-1 epidemiology needs further investigation.(AU)

Influence of chronic stretching on muscle performance: Systematic review.

The aim of the current study was to investigate the influence of chronic stretching on muscle performance (MP) by a systematic review. The search strategy included MEDLINE, PEDro, Cochrane CENTRAL, LILACS, and manual search from inception to June 2016. Randomized and controlled clinical trials, non-randomized, and single group studies that have analyzed the influence of flexibility training (FT) (using any stretching technique) on MP were included. Differently, studies with special populations (children, elderly, and people with any dysfunction/disease), and articles that have used FT protocols shorter than three weeks or 12 sessions were excluded. The MP assessment could have been performed by functional tests (e.g. jump, sprint, stretch-shortening cycle tasks), isometric contractions, and/or isotonic contractions. Twenty-eight studies were included out of 513. Seven studies evaluated MP by stretch-shortening cycle tasks, Ten studies evaluated MP by isometric contractions, and 13 studies assessed MP by isotonic contractions. We were unable to perform a meta-analysis due to the high heterogeneity among the included studies. In an individual study level analysis, we identified that 14 studies found positive effects of chronic stretching on MP. The improvements were observed only in functional tests and isotonic contractions, isometric contractions were not affected by FT. Therefore, FT might have an influence on dynamic MP. However, more studies are necessary to confirm whether FT can positively affect MP.

Increased arterial stiffness assessed by pulse wave velocity in Behçet's disease and its association with the lipid profile.

OBJECTIVE: To evaluate the structural and functional properties of vessels in Behçet's Disease (BD) using carotid-femoral pulse wave velocity (PWV) and an echo-tracking system. METHODS: BD patients without traditional cardiovascular risk factors were selected. All BD patients performed PWV and carotid ultrasound. BD patients were divided into groups based on the presence of systemic (vascular and/or ocular and/or central nervous system involvement) and vascular involvement. Healthy controls age- and sex-matched with the same exclusion criteria were selected. RESULTS: A total of 23 BD patients (mean age 35.0 ± 7.6 years) had significantly higher PWV levels compared with controls (8.48 ± 1.14 vs. 7.53 ± 1.40 m/s, P = 0.017). Intima-media thickness (594.87 ± 138.61 vs. 561.08 ± 134.26 µm, P = 0.371), diastolic diameter (6383.78 ± 960.49 vs. 6447.65 ± 1159.73 µm, P = 0.840), distension (401.95 ± 117.72 vs. 337.91 ± 175.36 µm, P = 0.225) and relative distension (6.26 ± 2.83 vs. 5.42 ± 2.46 µm, P = 0.293) were similar in both groups. The systemic disease group had significantly higher levels of PWV (8.79 ± 1.21 vs. 7.88 ± 0.72 m/s, P = 0.036) compared to those with exclusive mucocutaneous manifestations. BD patients with vascular involvement had similar PWV and echo-tracking parameters compared to those without vascular involvement (P > 0.05), but had higher total and LDL cholesterol levels (P = 0.019 and P = 0.012, respectively). The multivariate linear regression analysis identified triglycerides as the most important factor in increasing PWV levels (P = 0.001) in BD. CONCLUSIONS: PWV is more useful than carotid ultrasound in detecting structural and functional vascular damage in BD and emphasizes the role of the disease itself in promoting these alterations. Our findings also reinforce the need for rigorous control of all risk factors in BD, particularly lipoproteins.

Early mortality in liver transplantation: bilirubin as predictor of outcome.

The shortage of donor organs and the long waiting lists have increased the need to better select liver transplant candidates using predictors of success. We reviewed the results of 29 liver transplantations performed from January 2002 to February 2003 analyzing the correlations with early mortality (30 days) of patient data, pretransplant laboratory data, warm ischemia time, intraoperations blood unit transfusions, and postoperative complications of prolonged mechanical ventilation, dialysis, and infection. Overall early mortality was 27.6% and 44% in fulminant hepatic failure (n = 9), there were four retransplants with one death, and two intraoperative deaths. Only pretransplant bilirubin (P =.045) and postoperative lactate levels (P =.002) were significantly different between alive versus dead patients. In this small population bilirubin was more related to death than the MELD score. Lactate levels, nonspecific predictor of death in shock syndromes were probably related to septic complications.

Elevated plasma phenylalanine concentrations may adversely affect bone status of phenylketonuric mice.

Children with phenylketonuric (PKU) are at risk for fractures. This study used a PKU murine model (PAH(enu-2)) to evaluate effects of moderate dietary protein restriction and elevated plasma phenylalanine concentration impact upon bone status. Fifty-four male weanling PKU and control mice were assigned to either an elemental phenylalanine (Phe)-restricted diet (treated) or Phe-unrestricted diet (untreated) with low or normal protein levels for 56 days. Untreated mice and control mice received equal amounts of dietary Phe; treated mice consumed prescribed dietary Phe to maintain plasma Phe concentrations between 120 and 480micromol/L. Plasma Phe, osteocalcin, and urine deoxypyridinoline (DPD)/creatinine were analysed at baseline and at days 28 and 56. Femur strength, bone mineral density (BMD) and bone mineral content (BMC) were analysed at day 56. Moderate protein restriction did not significantly affect bone status. Mean plasma Phe concentrations were significantly greater in untreated vs treated and control mice (p < 0.0001). Total body weight was significantly less in untreated vs control mice (p < 0.01). Mean femur weight was reduced in untreated mice vs both treated and control mice (p < 0.03). Untreated mice had smaller mean femur length than control mice (p < 0.002). Femur strength was greater in treated mice compared to control mice (p < 0.01) but not compared to untreated mice. No significant difference among groups was found in BMD and BMC. At day 56 there was a statistical trend (p < 0.056) towards higher urine DPD/creatinine excretion in untreated mice than in treated mice. Plasma Phe concentration was positively correlated with urine DPD/creatinine. These data suggested that hyperphenylalaninaemia may adversely affect bone status in PKU mice.

Nuclear respiratory factors 1 and 2 are upregulated in hearts from copper-deficient rats.

It is known that mitochondrial transcription factor A (mtTFA) plays a pivotal role in coordinating the expression of proteins in the nuclear and mitochondrial genomes as it pertains to mitochondrial biogenesis. Hearts from copper-deficient rats have elevated mtTFA levels compared to copper-adequate rats. This study evaluated whether two proteins that control activation of mtTFA by binding to its promotor, nuclear respiratory factors 1 (NRF-1) and 2 (NRF-2), are also upregulated prior to any upregulation of mtTFA. Long-Evans male rats were fed either copper-adequate or copper-deficient diets from weanling for periods of time up to 26 d. At d 26, mtTFA levels were elevated in the hearts from the copper-deficient rats, but not at earlier time points of 14, 18, and 22 d. However, NRF-1 and NRF-2 levels were increased at d 14 and 18, but not at the other two later time-points. These results revealed that the upregulation of mtTFA and mitochondrial biogenesis is preceded by upregulation of NRF-1 and NRF-2, which is consistent with the known molecular events controlling mitochondrial biogenesis in other systems.

Peroxisome proliferator-activated receptor gamma coactivator-1 promotes cardiac mitochondrial biogenesis.

Cardiac mitochondrial function is altered in a variety of inherited and acquired cardiovascular diseases. Recent studies have identified the transcriptional coactivator peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1) as a regulator of mitochondrial function in tissues specialized for thermogenesis, such as brown adipose. We sought to determine whether PGC-1 controlled mitochondrial biogenesis and energy-producing capacity in the heart, a tissue specialized for high-capacity ATP production. We found that PGC-1 gene expression is induced in the mouse heart after birth and in response to short-term fasting, conditions known to increase cardiac mitochondrial energy production. Forced expression of PGC-1 in cardiac myocytes in culture induced the expression of nuclear and mitochondrial genes involved in multiple mitochondrial energy-transduction/energy-production pathways, increased cellular mitochondrial number, and stimulated coupled respiration. Cardiac-specific overexpression of PGC-1 in transgenic mice resulted in uncontrolled mitochondrial proliferation in cardiac myocytes leading to loss of sarcomeric structure and a dilated cardiomyopathy. These results identify PGC-1 as a critical regulatory molecule in the control of cardiac mitochondrial number and function in response to energy demands.

Mitochondrial transcription factor A is increased but expression of ATP synthase beta subunit and medium-chain acyl-CoA dehydrogenase genes are decreased in hearts of copper-deficient rats.

The mechanism(s) by which impaired mitochondrial respiratory function and the accumulation of lipid droplets and mitochondria in hearts of copper-deficient rats occur remains unclear. It is not known whether specific components of the regulatory pathway involved in mitochondrial biogenesis, such as mitochondrial transcription factor A (mtTFA) and nuclear respiratory factors 1 and 2 (NRF-1 and NRF-2), are activated in copper deficiency. Little is known about gene expression of enzymes involved in fatty acid oxidation (FAO) in hearts of copper-deficient rats. Male weanling rats were fed copper-adequate (CuA), copper-deficient (CuD) or pair-fed (CuP) diets for 5 wk. Mitochondria and lipid droplet volume densities from electron micrographs were greater and there was an elevation in the mtTFA protein level in hearts of copper-deficient rats. DNA binding activities of NRF-1 and NRF-2 did not differ among the groups. Northern blot analysis of cardiac tissue revealed that transcripts of F(1)F(0)-ATP synthase subunit c were greater, but mRNA levels of ATP synthase beta subunit and the FAO enzyme, medium-chain acyl-CoA dehydrogenase (MCAD), were lower in hearts of copper-deficient rats. Long-chain acyl-CoA dehydrogenase (LCAD) mRNA levels did not differ among treatment groups. These results suggest that certain components of the mitochondrial biogenesis program are activated in hearts of copper-deficient rats. F(1)F(0)-ATP synthase beta subunit and MCAD transcript levels remain low, which may contribute to impaired mitochondrial respiratory function, decreased fatty acid utilization and lipid droplet accumulation in hearts of copper-deficient rats.

Marginal copper and high fat diet produce alterations in electrocardiograms and cardiac ultrastructure in male rats.

This study investigated whether a high fat diet in tandem with a marginal copper (Cu) diet exerts deleterious effects on copper status, cardiac morphology, and electrophysiology compared to a low-fat marginal copper diet. Male weanling Long-Evans rats were fed diets containing either marginal copper (42.5 mumol/kg) or adequate copper (97.6 mumol/kg), and low fat (50.0 g/kg) or high fat (150.0 g/kg) diet for 12 wk in a 2 x 2 factorial design. To simulate the western diet, fat was composed of a 1:2 polyunsaturated:saturated fatty acids using a coconut and corn oil mixture. High dietary fat increased liver Cu concentration. Marginal copper diets decreased liver Cu,Zn-superoxide dismutase activity. Dietary copper and fat level had no effect on volume densities of mitochondria and myofibril. However, lower mitochondrial pathologic scores were observed in the rats consuming the high fat diets. Marginal copper high fat diet prolonged atrial electric depolarization (PR) and ventricular electric depolarization and repolarization (QT) intervals. This study provided direct evidence that a high fat diet can exert detrimental effects on cardiac ultrastructure and lead to alterations in electrocardiograms. The combination of marginal copper-high fat diet appears to alter cardiac electric conductivity. Longer term studies should provide information more relevant to clinical situations and morphologic changes.

Heart murmurs, valvular regurgitation and electrical disturbances in copper-deficient genetically hypertensive, hypertrophic cardiomyopathic rats.

OBJECTIVE: Rats with a genetic tendency to develop hypertensive, hypertrophic cardiomyopathy were fed copper-deficient diets and their cardiac responses were investigated. METHODS: Five male weanling rats of the Long-Evans and SHHF/Mcc-fa(cp) strains were randomly selected to receive diets containing either adequate quantities of copper (94.5 micromol Cu/kg diet) or reduced quantities of copper (<15.8 micromol Cu/kg diet) for 6 weeks, (n=5 within each group). Echocardiograms and electrocardiograms were recorded and analyzed at the end of the 6-week interval. RESULTS: Electrocardiograms from copper deficient groups showed longer Q-T intervals and increased QRS amplitudes than controls. Both the copper deficient and control SHHF groups demonstrated significant QRS complex prolongation compared to Long-Evans rats. Echocardiography analysis showed significant increases in left ventricular area, free wall dimension, and myocardial cross-sectional areas in rats fed a copper deficient diet. The frequency of systolic cardiac murmurs increased in copper deficient rats and were related to the presence of valvular regurgitation as determined from echocardiography. DISCUSSION: However, the data do not suggest that a copper-deficient diet fed to a strain of rats genetically susceptible to heart disease later in life, hastens or worsens the onset of cardiac disease. The genetic predisposition and copper-deficient states exert independent effects upon the heart.

Cardiac hypertrophy in copper-deficient rats is owing to increased mitochondria.

Dietary copper depletion results in cardiac hypertrophy and ultrastructural alterations. The objective of this study was to determine the components that contribute to cardiac enlargement. Two groups (n = 4) of male, weaning, Sprague-Dawley rats were fed ad libitum with copper-adequate or copper-deficient diets for five weeks. Cross sectional transmission electron micrographs from both groups were evaluated using image analysis to quantify absolute area occupied by myocyte, mitochondria, myofibril, and other intracellular material. Copper-deficient rats had larger myocytes, increased area of mitochondria, and increased ratio of mitochondria:myofibril as well as mitochondria:myocyte. Copper deficiency did not change the absolute area occupied by myofibrils. These data suggested that increase in the absolute mitochondria area is the major contributory factor to the cardiac hypertrophy in copper deficiency. Under the conditions used, myofibril has minimal role toward contributing to the hypertrophic state. The pathology reported resembles human forms of genetic mitochondrial cardiomyopathies. The copper-deficient rat may be a useful model to investigate the underlying biochemical or molecular responses when peptides of enzymes are deleted.

Dietary iron deficiency results in cardiac eccentric hypertrophy in rats.

This study reports the presence of eccentric cardiac hypertrophy in rats made anemic by feeding an iron-deficient diet. Male weanling Sprague-Dawley rats were provided free access to diets either adequate (n=9) or inadequate in iron (n=8) for a period of 7 weeks from weanling or until 10 weeks of age. At that time, blood was obtained for hematocrit and hemoglobin determination, and liver and hearts were collected for further analysis. Liver non-heme iron levels confirmed that the rats were iron-deficient, and the very low hematocrit and hemoglobin values revealed the presence of physiological anemia. Despite the lighter body weights in the iron-deficient rats, this group had greater absolute heart weights and heart:body weight, clearly demonstrating the presence of cardiac hypertrophy. Iron-deficient rats had elevated heart rates but lower norepinephrine levels than control rats. Sagittal sectioning of all hearts allowed for the measurements of the wall thicknesses, lumen volume, and width dimensions. Results revealed significantly greater left ventricular lesser diameter, apical thickness, and left ventricular volume in hearts from iron-deficient rats compared to iron-adequate rats. The hypertrophy pattern present in iron-deficiency anemia is in contrast to other nutritional models of hypertrophy, such as copper-deficiency, where a concentric hypertrophy occurs both in the presence and absence of anemia.

Effect of a protective-ventilation strategy on mortality in the acute respiratory distress syndrome.

BACKGROUND: In patients with the acute respiratory distress syndrome, massive alveolar collapse and cyclic lung reopening and overdistention during mechanical ventilation may perpetuate alveolar injury. We determined whether a ventilatory strategy designed to minimize such lung injuries could reduce not only pulmonary complications but also mortality at 28 days in patients with the acute respiratory distress syndrome. METHODS: We randomly assigned 53 patients with early acute respiratory distress syndrome (including 28 described previously), all of whom were receiving identical hemodynamic and general support, to conventional or protective mechanical ventilation. Conventional ventilation was based on the strategy of maintaining the lowest positive end-expiratory pressure (PEEP) for acceptable oxygenation, with a tidal volume of 12 ml per kilogram of body weight and normal arterial carbon dioxide levels (35 to 38 mm Hg). Protective ventilation involved end-expiratory pressures above the lower inflection point on the static pressure-volume curve, a tidal volume of less than 6 ml per kilogram, driving pressures of less than 20 cm of water above the PEEP value, permissive hypercapnia, and preferential use of pressure-limited ventilatory modes. RESULTS: After 28 days, 11 of 29 patients (38 percent) in the protective-ventilation group had died, as compared with 17 of 24 (71 percent) in the conventional-ventilation group (P<0.001). The rates of weaning from mechanical ventilation were 66 percent in the protective-ventilation group and 29 percent in the conventional-ventilation group (P=0.005): the rates of clinical barotrauma were 7 percent and 42 percent, respectively (P=0.02), despite the use of higher PEEP and mean airway pressures in the protective-ventilation group. The difference in survival to hospital discharge was not significant; 13 of 29 patients (45 percent) in the protective-ventilation group died in the hospital, as compared with 17 of 24 in the conventional-ventilation group (71 percent, P=0.37). CONCLUSIONS: As compared with conventional ventilation, the protective strategy was associated with improved survival at 28 days, a higher rate of weaning from mechanical ventilation, and a lower rate of barotrauma in patients with the acute respiratory distress syndrome. Protective ventilation was not associated with a higher rate of survival to hospital discharge.

Temporal hemodynamic effects of permissive hypercapnia associated with ideal PEEP in ARDS.

The associated use of permissive hypercapnia (PHY) and high PEEP levels (PEEP(IDEAL)) has been recently indicated as part of a lung-protective-approach (LPA) in acute respiratory distress syndrome (ARDS). However, the net hemodynamic effect produced by this association is not known. We analyzed the temporal hemodynamic effects of this combined strategy in 48 patients (mean age 34 +/- 13 yr) with ARDS, focusing on its immediate (after 1 h), early (first 36 h), and late (2nd-7th d) consequences. Twenty-five patients were submitted to LPA--with the combined use of permissive hypercapnia (PHY), VT < 6 ml/kg, distending pressures above PEEP < 20 cm H2O, and PEEP 2 cm H2O above the lower inflection point on the static inspiratory P-V curve (P(FLEX))- and 23 control patients were submitted to conventional mechanical ventilation. LPA was initiated at once, resulting in an immediate increase in heart rate (p = 0.0002), cardiac output (p = 0.0002), oxygen delivery (DO2l, p = 0.0003), and mixed venous Po2 (p = 0.0006), with a maintained systemic oxygen consumption (p = 0.52). The mean pulmonary arterial pressure markedly increased (mean increment 8.8 mm Hg; p < 0.0001), but the pulmonary vascular resistance did not change (p = 0.32). Cardiac filling pressures increased (p < 0.001) and the systemic vascular resistance fell (p = 0.003). All these alterations were progressively attenuated in the course of the first 36 h, despite persisting hypercapnia. Plasma lactate suffered a progressive decrement along the early period in LPA but not in control patients (p < 0.0001). No hemodynamic consequences of LPA were noticed in the late period and renal function was preserved. A multivariate analysis suggested that these acute hyperdynamic effects were related to respiratory acidosis, with no depressant effects ascribed to high PEEP levels. In contrast, high plateau pressures were associated with cardiovascular depression. Thus, as long as sufficiently low distending pressures are concomitantly applied, the sudden installation of PHY plus PEEP(IDEAL) induces a transitory hyperdynamic state and pulmonary hypertension without harmful consequences to this young ARDS population.

Newer findings on a unified perspective of copper restriction and cardiomyopathy.

The cuproenzymes lysyl oxidase, cytochrome-c oxidase, and superoxide dismutase are key factors in understanding the cardiac hypertrophy and cardiomyopathy associated with dietary copper restriction. The role of copper in cardiac lipid and energy metabolism as a consequence of changes in some of these enzyme activities in comparison with what is known about normal cardiac substrate utilization is discussed here. While the decrease in the nuclear encoded subunits of cytochrome-c oxidase in hearts from copper-deficient rats is known, new evidence suggests that other factors, such as ATP synthase metabolism may be exerting an influence upon this observation. While this review focuses on newer knowledge about energy and fatty acid metabolism in copper deficiency, the extracellular matrix is considered as well. This complex interplay of extracellular and cellular events in copper restriction is outlined as a model for further studies of this unique model of concentric hypertrophy.

Cardiac nuclear encoded cytochrome c oxidase subunits are decreased with copper restriction but not iron restriction: gene expression, protein synthesis and heat shock protein aspects.

Hearts from rats fed a copper-deficient (Cu-) diet have decreased levels of nuclear-encoded peptides of cytochrome c oxidase (CCO). Studies were conducted to determine whether iron deficiency would lead to a similar finding, whether mRNA transcripts and the chaperonin heat shock proteins (HSP) 60 and 70 from hearts of Cu- rats were decreased as compared with copper-adequate controls and whether synthesis of mitochondrial and nuclear encoded peptides differed as affected by diet copper. In study 1, weanling rats were assigned to one of three groups (n = 6 in each group): (1) control copper and iron adequate fed rats; (2) Cu- rats and (3) iron-deficient (Fe-) rats. Western blotting of nonmyofibrillar cardiac proteins revealed that the nuclear encoded peptides of CCO from the Cu- rats were markedly decreased as compared with control and Fe- rats. Mitochondrial encoded subunits did not appear to differ by treatment groups. Iron-deficient rats had similar nuclear encoded peptide levels as those of controls. In study 2, mRNA transcripts from Cu- (n = 4) and control copper adequate (n = 4) rats did not appear to differ for subunits II and IV, which correspond to mitochondrial and nuclear encoded subunits, respectively. In study 3, levels of HSP 60 and 70 from hearts of Cu- rats (n = 3) did not differ from Cu+ rats (n = 3). In study 4, infusion of 3H-(4,5)-leucine into the hearts of Cu+ and Cu- rats suggested there was no difference in synthesis of the nuclear encoded peptides by copper status and some indication there was enhanced breakdown of the nuclear encoded peptides among the Cu- rats. As expected, more isotope was incorporated into the mitochondria of Cu- rats than Cu+ rats. These results demonstrate an independent effect of copper upon the apparent decrease in the nuclear encoded subunits of CCO, the effect of copper upon the CCO subunits is probably post-transcriptional and that translocation of the nuclear encoded subunits from the ribosomes to the mitochondria via the chaperonin proteins is not a primary defect in explaining these observations in hearts from Cu- rats and synthesis of the nuclear encoded subunits of CCO in not impaired in copper deficiency.

Decreased nuclear encoded subunits of cytochrome c oxidase and increased copper, zinc-superoxide dismutase activity are found in cardiomyopathic human hearts.

Mineral concentrations, copper, zinc-superoxide dismutase and cytochrome c oxidase subunits in human cardiomyopathic heart explants were compared with noncardiomyopathic hearts from autopsy subjects. Iron was reduced in cardiomyopathic hearts, but the zinc:iron ratio was higher in cardiomyopathic hearts. Copper, zinc-superoxide dismutase activity was increased in cardiomyopathic human hearts compared to the noncardiomyopathic hearts. In a subsample of specimens analyzed, the nuclear encoded subunits of cytochrome c oxidase were diminished in the cardiomyopathic hearts. The decreases have been observed in rodents fed copper-deficient diets. However, in this study heart copper levels did not differ by disease status.

Aspects of cardiomyopathy in copper-deficient pigs. Electrocardiography, echocardiography, and ultrastructural findings.

Pigs were made copper (Cu)-deficient to evaluate cardiac function and pathology, and electrocardiography. Fifteen-day-old pigs were fed a Cu-restricted diet over an 8 wk period and compared to Cu-adequate diet-fed pigs. Cardiac effects were examined concerning gross morphometry and ultrastructure, echocardiography, and electrocardiography, as well as serum cholesterol levels. The Cu-restricted diet-fed pigs exhibited a marked deceleration of growth and lower hematocrit, hemoglobin, and liver and serum Cu concentrations compared to the Cu-adequate diet-fed pigs. The Cu-restricted diet-fed pigs developed a significantly greater heart weight:body weight ratio, along with greater diastolic measures of ventricular wall and internal dimension relative to body weight. Electrocardiography in the Cu-restricted diet-fed pigs revealed one instance of electrical alternans and an intraventricular conduction disturbance and several instances of T-wave inversion. The Cu-restricted pigs also displayed a prolonged QT interval at the closure of study. Increased mitochondrial volume density and mitochondria:myofibril volume density ratio were observed in the Cu-restricted pig electron micrographs along with excessive lipid and glycogen inclusion and focal degradation of Z-lines, intercalated disk, and sarcomeres. Copper-restriction in young pigs results in cardiac pathology and electrical disturbances. These alterations are similar to those reported for young Cu-restricted rodents. Given then that many cardiac manifestations of developed Cu-deficiency appear conserved across specie lines, the potential for human disturbances in response to severe Cu-deficiency may be plausible.

Deliberations and evaluations of the approaches, endpoints and paradigms for dietary recommendations about copper.

Important aspects of copper nutrition were collected from all 10 editions of the Recommended Dietary Allowance along with the history of the paradigm concept according to Thomas Kuhn. Important anomalies in copper nutrition, such as the easy accessibility to diets containing considerably less copper than the estimated safe and adequate daily dietary intake are reviewed. Important experiments with animals are compared with copper depletion experiments with humans. Data support the belief that people respond to diets low in copper similarly to animals and that measurement of copper in blood plasma generally is useless in assessing nutritional status. If common diets low in copper are consumed regularly during pregnancy, maternal stores of copper will be depleted. Although there is some evidence of lower copper in heart and major blood vessels in elderly people, it is premature to suggest different intakes for adults of different ages. Although consideration of cardiovascular data in establishing an RDA for copper may seem to be a new paradigm, considerations of general health and well being have long contributed to establishing RDAs. Dietary copper can be increased by adhering to the advice symbolized by the food pyramid.