Long-term safety of early consumption of Lactobacillus fermentum CECT5716: A 3-year follow-up of a randomized controlled trial.

Lactobacillus fermentum CECT5716 is a probiotic strain originally isolated from human breast milk. Previous clinical studies in infants showed that the early administration of a milk formula containing this probiotic strain was safe and may be useful for the prevention of community-acquired infections. This is a 3-year follow-up study aimed at evaluating the long-term effects produced by the early consumption of an infant formula supplemented with L. fermentum CECT5716 (experimental group, EG) compared with a control formula without the probiotic (control group, CG). The infants included in this follow-up study had previously completed a 5-month randomized double-blind controlled trial (from 1 to 6 months of age), where the safety and tolerance of the probiotic formula was evaluated. The main outcome of the follow-up study was the growth of the children. The secondary outcomes included the incidence of infectious and non-infectious diseases, parameters related with intestinal function and faecal microbiota. At 3 years, the mean values of weight, length and head circumference were similar in children of the EG compared with those of the CG. No differences were observed in the incidence of infectious and non-infectious diseases or disorders related with intestinal function. The pattern of faecal microbiota was also similar between both groups. In conclusion, this 3-year study shows that the early administration of the probiotic of L. fermentum CECT5716 in an infant formula is safe and it does not produce measurable differences in children compared with a control formula.

Gut microbiota and voluntary alcohol consumption.

Alcohol is part of the usual diet of millions of individuals worldwide. However, not all individuals who drink alcohol experience the same effects, nor will everyone develop an alcohol use disorder. Here we propose that the intestinal microbiota (IMB) helps explain the different consumption patterns of alcohol among individuals. 507 humans participated in this study and alcohol consumption and IMB composition were analyzed. On the other hand, in 80 adult male Wistar rats, behavioral tests, alcohol intoxication, fecal transplantation, administration of antibiotics and collection of fecal samples were performed. For identification and relative quantification of bacterial taxa was used the bacterial 16 S ribosomal RNA gene. In humans, we found that heavy episodic drinking is associated with a specific stool type phenotype (type 1, according to Bristol Stool Scale; p < 0.05) and with an increase in the abundance of Actinobacteria (p < 0.05). Next, using rats, we demonstrate that the transfer of IMB from alcohol-intoxicated animals causes an increase in voluntary alcohol consumption in transplant-recipient animals (p < 0.001). The relative quantification data indicate that the genus Porphyromonas could be associated with the effect on voluntary alcohol consumption. We also show that gut microbiota depletion by antibiotics administration causes a reduction in alcohol consumption (p < 0.001) and altered the relative abundance of relevant phyla such as Firmicutes, Bacteroidetes or Cyanobacteria (p < 0.05), among others. Benjamini-Hochberg false discovery rate (FDR) correction was performed for multiple comparisons. These studies reveal some of the consequences of alcohol on the IMB and provide evidence that manipulation of IMB may alter voluntary alcohol consumption.

Efficacy and safety of conversion from twice-daily to once-daily tacrolimus in a large cohort of stable kidney transplant recipients.

Prolonged-release tacrolimus was developed to provide a more convenient once-daily dosing that could improve patient adherence. We conducted a multicenter, prospective, observational, 12-month study to describe the efficacy, safety and patient preference of conversion from tacrolimus twice-daily to once-daily formulation in stable kidney transplant recipients in routine clinical practice. Conversion was made on a 1 mg: 1 mg basis (1 mg: 1.1 mg in patients with trough levels <6 ng/mL). The study included 1832 patients (mean age (± SD): 50.0 ± 13.4 years; 62.7% male). After conversion, a modest reduction in tacrolimus trough levels, necessitating an increase in daily dose, was observed (mean changes at 12 months of -9.1% and +1.24%, respectively; p < 0.0001). Mean glomerular filtration rate did not change significantly (56.5 ± 19.7 mL/min at conversion vs. 55.7 ± 20.6 mL/min at 12 months). Proteinuria, blood pressure, lipid, hepatic and glucose parameters remained stable. Eight patients (0.4%) had acute rejection and 34 patients (1.85%) discontinued treatment. Almost all patients (99.4%) preferred the once-daily formulation, because of less frequent dosing (66%) and improved adherence (34%). In conclusion, at similar doses to twice-daily tacrolimus, once-daily formulation provided stable renal function, a low acute rejection rate, and good tolerability in stable kidney transplant recipients in the routine clinical practice setting.

Daily consumption of milk enriched with fish oil, oleic acid, minerals and vitamins reduces cell adhesion molecules in healthy children.

BACKGROUND AND AIMS: Several studies have suggested that polyunsaturated fatty acids, vitamins and minerals have beneficial effects on lipid profile and systemic inflammation in adults. METHODS AND RESULTS: We examined the effects of a daily intake of milk enriched with longchain polyunsaturated fatty acids, oleic acid, carbohydrates, vitamins, minerals and low in saturated fatty acids (SFAs) for 5 months, on several cardiovascular (CVD) risk biomarkers in healthy children aged 8-14 years. In a randomized double-blind placebo-controlled trial, a total of 107 children of both genders were assigned to two study groups: 1) a supplemented group (SG, n=53) who consumed 0.6 L/day of an enriched dairy product, and 2) a control group (CG, n=54) who consumed 0.6 L/day of standard whole milk. Both groups consumed the dairy drinks for 5 months, in addition to their usual diet. Serum levels of adhesion molecules as indices of vascular endothelial cell activation were assessed in both groups at 0 and 5 months as well as white blood cell counts, lipid profile, serum proteins, total serum calcium, 25-OH vitamin D, glucose, insulin and adiponectin. In the enriched dairy drink supplemented group, adhesion molecules E-selectin and ICAM-1 as well as lymphocyte levels decreased while plasma docosahexaenoic acid (DHA) and serum calcium concentrations increased. In the control group, serum total protein, transferrin, total cholesterol, HDL-cholesterol and adiponectin concentrations decreased. CONCLUSION: The consumption of a milk enriched with fish oil, oleic acid, minerals and vitamins reduced indices of endothelial cell activation in the studied group of healthy children.

Tracking the dynamic ecological history of a tropical urban estuary as it responds to human pressures.

Coastal cities in tropical areas are often low-lying and vulnerable to the effects of flooding and storms. San Juan, Puerto Rico is a good example of this. It is built around a lagoon-channel complex called the San Juan Bay Estuary (SJBE). A critical channel in the estuary, the Caño Martín Peña, has filled in and now frequently floods the surrounding communities with sewage-enriched waters, causing a series of human health and ecological problems. Sediment core analyses indicate that portions of the SJBE now function as settling basins. High urban and sewage runoff to the Caño contributes nitrogen (N), but stable isotope and sediment nutrient analyses indicate that this runoff may also enhance conditions for coupled sulfate reduction-nitrogen fixation. The amount of 'new' bioavailable N created from inert atmospheric N2 gas may meet or exceed that from the runoff into the Caño Martín Peña. The ecological consequences of this appear to extend beyond the ponded channel, potentially contributing to the poor water quality of the SJBE, greater than contaminated runoff alone.

Ciudades costeras en los trópicos generalmente se encuentran localizadas en lugares de baja elevación y vulnerables a los efectos de tormentas e inundaciones. San Juan, Puerto Rico es un buen ejemplo de esto. Esta ciudad fue construida alrededor de un sistema de lagunas y canales que se conoce como el Estuario de la Bahía de San Juan. Un canal crítico en este sistema es el Caño Martín Peña que en el pasado fue rellenado con sedimentos causando inundaciones en las comunidades vecinas. Estas aguas de escorrentía incluyen aguas residuales y aumentado el riesgo a problemas de salud pública y del ambiente. Análisis de los sedimentos indican que porciones de este sistema funcionan como lagunas de sedimentación. Gran flujo de aguas residuales y escorrentía urbana hacia el Caño aportan nitrógeno (N), pero el análisis de sedimentos y nutrientes por isótopos estables indica que esta escorrentía también aumenta las condiciones por procesos acoplados de reducción de sulfato y fijación de nitrógeno. La cantidad de 'nuevo' N biodisponible creado del gas nitrógeno inerte atmosférico podría lograr o exceder esa fijación del nitrógeno derivado de la escorrentía hacia el Caño. Las consecuencias ecológicas de esto parecen extenderse más allá de este canal estancado afectando así la calidad del agua en el Estuario, mayor aún que los contaminantes encontrados en la escorrentía pluvial por sí sola.

Adult-onset hypothyroidism increases ethanol consumption.

RATIONALE: Only in Europe it can be estimated that more than 20 million of people would be affected by hypothyroidism in some moment of their life. Given that ethanol consumption is so frequent, it would be reasonable to ask what the consequences of ethanol consumption in those individuals affected by hypothyroidism are. OBJECTIVES: To study the interaction between hypothyroidism and ethanol consumption. METHODS: We study ethanol consumption in a rat model of methyl-mercaptoimidazole-induced-adult-onset hypothyroidism and thyroid T4/T3 hormone supplementation. Also, we studied the effects of ethanol on motor activity, memory, and anxiety. RESULTS: We found that hypothyroidism increased the voluntary ethanol consumption and that this was enhanced by thyroid hormone supplementation. Hypothyroidism was associated with motor hyperactivity which was prevented either by T4/T3 supplementation or ethanol. The relationship between hypothyroidism, ethanol, and anxiety was more complex. In an anxiogenic context, hypothyroidism and T4/T3 supplementation would increase immobility, an anxiety-like behavior, while in a less anxiogenic context would decrease rearing, a behavior related to anxiety. Regarding memory, acute ethanol administration did not alter episodic-like memory in hypothyroid rats. Gene expression of enzymes involved in the metabolism of ethanol, i.e., Adh1 and Aldh2, were altered by hypothyroidism and T4/T3 supplementation. CONCLUSIONS: Our results suggest that hypothyroid patients would need personalized attention in terms of ethanol consumption. In addition, they point that it would be useful to embrace the thyroid axis in the study of ethanol addiction, including as a possible therapeutic target for the treatment of alcoholism and its comorbid disorders.

Wastewater reclamation through a combination of natural systems (infiltration-percolation and constructed wetlands): a solution for small communities.

The decision on technologies used for reclaiming wastewater appears as important as a consequence of the implications on the economic, environmental and health conditions of societies. The problem arises when deciding how to deal with wastewater in small communities, because the costs of implementing and operating small, intensive wastewater treatment plants are unacceptable and can lead to financing and operation problems. Extensive treatment systems can be a good solution, where space is available. This paper presents the combination of two soft technologies (infiltration-percolation and constructed wetlands) to treat and reclaim wastewater. The obtained results show that the infiltration-percolation effluent presents a quality enough to be reused for irrigation of industrial crops, nurseries, fodder, cereals and oleaginous seeds, ornamental flower production; industrial cooling; impoundments, water bodies, and streams for recreational use in which the public's contact with the water is not permitted; and irrigation of forested areas, landscape areas and restricted access areas. Moreover, the combination of infiltration-percolation and constructed wetlands increases the list of final reclamation to the following: irrigation of pasture for milk or meat animals, crops for canning industry, crops not raw-consumed, fruit trees except by sprinkling, aquaculture; and aquifer recharge by localised percolation through the soil.

Wastewater infiltration percolation for water reuse and receiving body protection: thirteen years' experience in Spain.

Infiltration percolation (IP) is an extensive technology to treat primary or secondary effluents of small and middle size communities before reuse or disposal to sensitive receiving bodies. Thirteen years of implementation of IP in Spain has highlighted the necessity to abide by defined design and construction rules and operation conditions in order to achieve consistently the treatment objectives and guarantee a long lasting treatment capacity. From this experience, high care should be taken of (i) the characteristics of the sand constituting the filter, (ii) the drainage conditions, (iii) the influent spreading over the infiltration surface and (iv) the risks related to recurrent overloading. Simple monitoring measures are suggested in order to improve the reliability of IP plants.

Wastewater reclamation systems in small communities.

The demands established in the rules and regulations by the administration in Catalonia seem to exclude small communities from wastewater reclamation and reuse, due to the comparatively high costs associated with the practice at small scale. In the framework of the DRAC project (Demonstration on Wastewater Reclamation and Reuse in Catalonia) two different pre-treatment systems, one extensive (infiltration-percolation) and another intensive (ring filter), each one followed by chlorine dioxide disinfection, were tested in order to be applied for small communities wastewater reclamation and reuse. The results of this study show that infiltration-percolation systems remove very efficiently physico-chemical contaminants and microorganisms. The ring filter system does not show a significant removal rate of contaminants, The use of infiltration-percolation as a pre-treatment for advanced chemical disinfection allows reducing the dose of disinfectant and the contact time needed to achieve a specific water quality, and diminishes disinfection byproducts (DBPs) generation. Therefore, this reclamation line is suitable for small communities due to its efficiency and low cost. However, further studies are needed in relation to the removal mechanisms of microorganisms, organic compounds in IP systems and the possible DBPs formation using chlorine dioxide.

[Intake of an iron-supplemented milk formula as a preventive measure to avoid low iron status in 1-3 year-olds]. / Ingesta de una fórmula láctea suplementada con hierro como medida preventiva del déficit de hierro en niños de 1 a 3 años de edad.

OBJECTIVE: Low iron status is a well known risk factor for iron deficiency anemia in infants and young children. The aim of the present study was to evaluate the influence of an iron-fortified toddler formula on iron status in 1-3 year-olds. PATIENTS AND METHODS: Thirty-three healthy infants and young children were assigned to two groups that received 500 mL/day of and iron-fortified toddler formula or 500 mL/day of unmodified cow's milk for 4 months. Allocation was random and double-blind. Daily dietary intake was calculated by dietary evaluation, and iron nutritional status was assessed (hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, serum iron, ferritin, and transferrin). RESULTS: At enrollment, no anemia was found in either group, although hemoglobin concentration and hematocrit were significantly lower in the toddler formula group than in the unmodified cow's milk group. However, these differences disappeared at the end of the intervention period. After 4 months, the toddler formula group showed significantly higher serum ferritin and lower serum transferrin concentrations than the cow's milk group. CONCLUSION: Intake of iron-supplemented toddler formula for 4 months in 1-3 year-olds is more effective in maintaining iron nutritional status than cow's milk.

[All-trans retinoic acid syndrome [corrected] and renal cortical necrosis]. / Síndrome del ácido transretinoico y necrosis cortical renal.

We described a patient with acute promyelocytic leukemia (APL) who developed all-trans retinoic acid syndrome (ATRAS). ATRAS presents in patients with APL treated with all-trans retinoic acid (ATRA). It has an incidence from 5-27% with mortality of 29%. ATRAS clinical manifestations are fever, hypotension, respiratory, renal and hepatic insufficiency, lung infiltrates, pleural and pericardic effusion, and generalized edema. It is secondary to ATRA effect on promyelocyte differentiation, which causes systemic inflammatory response syndrome, endothelium damage with increase in capillary permeability, microcirculation obstruction, and tissue infiltration. Treatment is based on ATRA suspension, steroids and support measures.

[Stress response under continuous infusion of remifentanil compared to bolus doses of fentanyl assessed by levels of cytokines, C-reactive protein, and cortisol during and after abdominal hysterectomy]. / Estudio de la respuesta al estrés en dos técnicas analgésicas (remifentanilo continuo frente a fentanilo en bolos) valorando diferentes marcadores (citocinas, proteína C reactiva y cortisol) en el intra y postoperatorio de histerectomías abdominales.

OBJECTIVES: Surgery and anesthetic method have immunomodulating effects on hemodynamic response and stress. We compared the effects of 2 intraoperative analgesic regimens on patients undergoing abdominal hysterectomy. MATERIAL AND METHODS: We conducted a randomized double-blind trial in ASA 1 and 2 patients undergoing abdominal hysterectomy under balanced anesthesia. Twenty-nine patients were randomized to 2 groups. One group received analgesia by infusion of remifentanil plus morphine and nonsteroidal anti-inflammatory drugs as rescue medications; the other received conventional analgesia with bolus doses of fentanyl according to changes in hemodynamic variables. We measured levels of proinflammatory (interleukin [IL]-6) and antiinflammatory (IL-10) cytokines, cortisol, and C-reactive protein preoperatively, at incision, and at 1, 4 and 24 hours after surgery. RESULTS: There were no significant differences between the 2 groups in terms of the markers studied at baseline. In each group, however, there were significant changes from baseline at the various points in time. IL-6 and IL-10 levels were significantly elevated (P < .05) at 4 hours. The changes in cortisol levels were significantly different at 1 and 4 hours. Finally, there were significant increases in C-reactive protein at 24 hours. CONCLUSIONS: Unlike other clinical trials, our study detected no differences between the 2 techniques in response to surgical stress evaluated by analyzing concentrations of pro- and anti-inflammatory cytokines, cortisol, and C-reactive protein.

One-month administration of hydroxytyrosol, a phenolic antioxidant present in olive oil, to hyperlipemic rabbits improves blood lipid profile, antioxidant status and reduces atherosclerosis development.

The present study analysed the effects of hydroxytyrosol (HT) on blood lipids, antioxidant status and the progression of aortic lesions in hyperlipemic rabbits. Sixty-four rabbits were distributed into eight groups of animals (n = 8). Animal groups C, A and H were fed for 1-month with a control diet containing sunflower oil (C), an atherogenic diet (A) high in saturated fat and cholesterol or the A diet together with HT, respectively. The other five groups were fed for 2-months with diets C or A (groups CC or AA, respectively), or for 1-month with the A-diet followed by a further month with diet C, extra virgin olive oil diet (O) or diet C with HT (groups AC, AO and AH, respectively). Four milligram of HT/kg body weight were used in the study. Fifty and 42% decrease in total cholesterol and triacylglycerols, respectively, and a 2.3-fold increase in HDL-cholesterol were observed in the AH group but not in the H group. The HT-supplemented groups improved their antioxidant status and reduced the size of atherosclerotic lesions measured as intimal layer areas of the aortic arch when compared with control animals. We conclude that HT supplementation may have cardioprotective effects in vivo.

[Parvovirus B9 infection in a renal transplant recipient. Diagnosis by detection of viral genome in peripheral blood]. / Infección por parvovirus B19 en trasplante renal. Diagnóstico por detección del genoma viral en sangre periférica.

Parvovirus B19 can produce a picture known as pure red blood aplasia in recipients of solid organ. Occasionally the viruses cause decrease of the other blood cells, and various extra-hematologic manifestations. Common diagnosis is realised by bone marrow examination. The diagnostic value of the viral genome in the blood stream is not well defined. We reported the case of a male of 17 years of age, whose diagnosis was done by repeated determinations of the viral parvovirus B19 genome in peripheral blood. It was confirmed by a biopsy of the iliac crest. The patient was treated with unspecific IgG immunoglobulins, with complete recovery from the symptoms and signs. It did not have any recurrence of the disease. This case suggests that the realisation of PCR of Parvovirus B19 in renal transplant patients with pure red cell aplasia could be of greater interest in the diagnosis and monitoring of the disease. The detection of the viral genome could avoid the administration of unnecessary blood transfusions, and possibly the realization of bone marrow biopsy.

[Cardiovascular effects of omega-3-fatty acids and alternatives to increase their intake]. / Efectos cardiovasculares de los ácidos grasos omega-3 y alternativas para incrementar su ingesta.

Cardiovascular diseases are the main mortality cause in Europe, the USA and a great extent of Asia. There are several risk factors associated with cardiovascular diseases, such as increased total cholesterol, homocysteine and triglycerides, hypertension, diabetes, and reduced levels of HDL-cholesterol. Many of these risk factors are diet influenced. In spite of the great amount of foods enriched with n-3 fatty acids available at the market, the knowledge about the effects produced by regular intake of these foods still is a challenge in the majority of cases. It appears that intake of foods enriches with n-3 polyunsatured fatty acids is an option that may be effective in reducing risk factors for diseases, by substituting supplements without modifying consumer's alimentary habits. Also shown are the outcomes from a nutritional study undergone with a functional milk-bases food that contains n-3 fatty acids, oleic acid and vitamins.

Safety and efficacy of human breast milk Lactobacillus fermentum CECT 5716. A mini-review of studies with infant formulae.

Human breast milk has been described as a source of lactic acid bacteria. Lactobacillus fermentum CECT5716 is a human breast milk strain whose probiotic properties, safety and efficacy has been demonstrated in vitro and in vivo, including controlled trials with human adults. Since the origin of this probiotic strain is human breast milk, we aimed to investigate the safety and efficacy of an infant and a follow-on formulas supplemented with this strain of L. fermentum. We carried out two randomised controlled trials: one trial with infants of 6-12 months of age (follow-on formula study) and another one with infants from 1 to 5 months of age (infant formula study). The results from the trials showed that the probiotic formulas were safe, well tolerated and might be useful for the prevention of community-acquired infections.

Antibodies against pex14p block ATP-independent binding of matrix proteins to peroxisomes in vitro.

The membrane protein Pex14p is a key component of the protein import machinery of peroxisomes. Antibodies raised against human Pex14p recognise a 66 kDa protein in sunflower glyoxysomes (HaPex14p) and immunoprecipitate in vitro-translated Arabidopsis Pex14p (AtPex14p). These antibodies inhibit the ATP-independent binding to sunflower peroxisome membranes of peroxisome targeting signal type (PTS) 1- and PTS2-targeted matrix proteins, but not an integral membrane protein. These results suggest that Pex14p functions before the ATP-dependent step of peroxisome assembly.

Superoxide radical generation in peroxisomal membranes: evidence for the participation of the 18 kDa integral membrane polypeptide.

Peroxisomes were isolated from pea (Pisum sativum L.) leaves and the peroxisomal membranes were purified by treatment with Na2CO3. The production of superoxide radicals (O2) induced by NADH was investigated in peroxisomal membranes from intact organelles incubated with proteases (pronase E and proteinase K). Under isoosmotic conditions, in the presence of pronase E, the production of O2-. radicals was inhibited by 80%. SDS-PAGE of peroxisomal membranes after protease treatment demonstrated a decrease in the 18-kDa PMP. This suggests that this polypeptide has a small fragment exposed to the cytosolic side of the peroxisomal membrane which is essential for O2-. production. The 18-kDa PMP was purified by preparative SDS-PAGE and in the reconstituted protein the NADH-driven production of O2-. radicals was investigated. The isolated polypeptide showed a high generation rate of superoxide (about 300 nmol O2-. x mg-1 protein x min-1) which was completely inhibited by 50 mM pyridine. The 18-kDa PMP was recognized by a polyclonal antibody against Cyt b5 from human erythrocytes. The presence of b-type cytochrome in peroxisomal membranes was demonstrated by difference spectroscopy. Results obtained show that in the NADH-dependent O2-. radical generating system of peroxisomal membranes, the 18-kDa integral membrane polypeptide, which appears to be Cyt b5, is clearly involved in superoxide radical production.

Immunocytochemical localization of copper,zinc superoxide dismutase in peroxisomes from watermelon (Citrullus vulgaris Schrad.) cotyledons.

In previous works using cell fractionation methods we demonstrated the presence of a Cu,Zn-containing superoxide dismutase in peroxisomes from watermelon cotyledons. In this work, this intracellular localization was evaluated by using western blot and EM immunocytochemical analysis with a polyclonal antibody against peroxisomal Cu,Zn-SOD II from watermelon cotyledons. In crude extracts from 6-day old cotyledons, analysis by western blot showed two cross-reactivity bands which belonged to the isozymes Cu,Zn-SOD I and Cu,Zn-SOD II. In peroxisomes purified by sucrose density-gradient centrifugation only one cross-reactivity band was found in the peroxisomal matrix which corresponded to the isozyme Cu,Zn-SOD II. When SOD activity was assayed in purified peroxisomes two isozymes were detected, Cu,Zn-SOD II in the matrix, and a Mn-SOD in the membrane fraction which was removed by sodium carbonate washing. EM immunocytochemistry of Cu,Zn-SOD on sections of 6-day old cotyledons, showed that gold label was mainly localized over plastids and also in peroxisomes and the cytosol, whereas mitochondria did not label for Cu,Zn-SOD.

Purification of catalase from pea leaf peroxisomes: identification of five different isoforms.

Catalase activity was analyzed in seven organs of pea (Pisum sativum L.) plants: leaves, seeds, flowers, shoots, whole fruits, pods and roots. Leaves showed the highest activity followed by whole fruits and flowers. Catalase was purified from pea leaf peroxisomes. These organelles were isolated from leaves by differential and sucrose density-gradient centrifugation, and catalase was purified by two steps involving anion exchange and hydrophobic chromatography using a Fast Protein Liquid Chromatography system. Pure catalase had a specific activity of 953 mmol H2O2 min(-1) mg(-1) protein and was purified 1000-fold, with a yield of about 19 microg enzyme per kg of pea leaves. Analysis by SDS-PAGE and immunoblot showed that the pea catalase was composed of subunits of 57 kDa. Ultraviolet and visible absorption spectra of the enzyme showed two absorption maxima at 252 and 400 nm with molar extinction coefficients of 2.14 x 10(6) and 7.56 x 10(6) M(-1) cm(-1), respectively. By isoelectric focusing (pH 5-7), five different isoforms were identified and designated as CAT1-5, with isoelectric points of 6.41, 6.36, 6.16, 6.13 and 6.09, respectively. All the catalase isoforms contained a subunit of 57 kDa. Post-embedment, EM immunogold labelling of catalase showed a uniform distribution of the enzyme inside the matrix and core of pea leaf peroxisomes.