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J Miquel

Publications and source records attributed to J Miquel.

At least 19 recordsLinked to original sources
PubMed2004

Thiolic antioxidant supplementation of the diet reverses age-related behavioural dysfunction in prematurely ageing mice.

We have studied in a model of premature ageing in mice based on their impaired behavioural response in a simple T-maze test the effect of the ingestion of thioproline (TP) plus N-acetylcysteine (NAC) (0.1% w/w of each antioxidant) by female and male mice of Swiss and BALB/c strains on performance in two behaviour tests. The antioxidant treatment (4 weeks in two different periods of life, i.e., adult and old age) protected all animals against early-age-associated behavioural impairment, but this improvement was more evident in the prematurely ageing mice (PAM) in comparison to the control group or non-prematurely ageing mice (NPAM). An improvement of the exploratory activity and neuromuscular coordination after the thiolic antioxidant treatment was found in the PAM, bringing the behavioural parameters to the NPAM levels. These effects could be due to the glutathione precursor role of NAC and TP that replenish the intracellular reduced glutathione (GSH) levels despite advancing age. In conclusion, diet supplementation with thiolic compounds appears to be an effective therapy for protection against early behavioural decline in prematurely ageing mice.

Aging↗
PubMed2004

Helminth parasites of the Eurasian otter Lutra lutra in southwest Europe.

The helminth fauna in 109 Eurasian otters (Lutra lutra L.) from France, Portugal and Spain was analysed, together with 56 faecal samples collected in Portugal and 23 fresh stools from otters included in a reintroduction programme. Seven helminth species were found in L. lutra in southwest Europe: Phagicola sp. (Trematoda), Aonchotheca putorii, Eucoleus schvalovoj, Strongyloides lutrae, Anisakis (third stage larvae) and Dirofilaria immitis (Nematoda), and Gigantorhynchus sp. (Acanthocephala). Eucoleus schvalovoj was the dominant species throughout southwest Europe. Strongyloides lutrae was significantly more prevalent in the Iberian Peninsula than in France. Apart from these two dominant nematodes and A. putorii, the other helminth species were incidental parasites of L. lutra in southwest Europe. The helminth fauna of L. lutra in southwest Europe is, in general, poorer than that reported in eastern Europe and in all other aquatic mustelids in southwest Europe. Phagicola specimens are reported for the first time in a non-marine wild carnivore in Europe. The prevalences of E. schvalovoj and S. lutrae obtained by necropsy were higher than those observed by coprological analysis using a formalin-ether concentration method (Ritchie). Nevertheless, the culture of fresh faeces appears to be the best method to study infection of L. lutra by Strongyloides.

Acanthocephala↗
PubMed2002

The curcuma antioxidants: pharmacological effects and prospects for future clinical use. A review.

In agreement with the predictions of the oxygen-stress theory of aging and age-related degenerative diseases, diet supplementation with a number of phenolic or thiolic antioxidants has been able to increase the life span of laboratory animals, protect against senescent immune decline and preserve the respiratory function of aged mitochondria. In addition to the above, more recent data reviewed here suggest that the polyphenolic compound curcumin and related non-toxic antioxidants from the rhizome of the spice plant Curcuma longa have a favorable effect on experimental mouse tumorigenesis as well as on inflammatory processes such as psoriasis and ethanol-caused hepatic injury. Our own research has focused on the effects of diet supplementation with an antioxidant-rich hydroalcoholic extract of the curcuma rhizome on key risk factors of atherogenesis and related cardiovascular disease. Our reviewed data show that, in human healthy subjects, the daily intake of 200 mg of the above extract results in a decrease in total blood lipid peroxides as well as in HDL and LDL-lipid peroxidation. This anti-atherogenic effect was accompanied by a curcuma antioxidant-induced normalization of the plasma levels of fibrinogen and of the apo B/apo A ratio, that may also decrease the cardiovascular risk. The reviewed literature indicates that curcumin and related plant co-antioxidants are powerful anti-inflammatory agents. Further, since they potentiate the anti-atherogenic effect of alpha-tocopherol, more extensive clinical testing of their probable usefulness in cardiovascular risk reduction seems justified.

Journal Article↗
PubMed2002

The amount of thiolic antioxidant ingestion needed to improve several immune functions is higher in aged than in adult mice.

With aging there is an increase of oxidative stress due to an imbalance between the oxidant production and the antioxidant levels in favor of the former. Since immune cell functions are specially linked to reactive oxygen species (ROS) generation, the oxidant/antioxidant balance is essential for these cells. Although low levels of antioxidants cause a decrease in immune function, very high levels of antioxidant compounds could show prooxidant effects. In the present work, we have studied the effect of diet supplementation, for 4 weeks, with two different doses of two thiolic antioxidants, namely thioproline (TP) and N-acetylcysteine (NAC), at 0.1% (w/w) and 0.3% (w/w, of each antioxidant) on the main immune system cells, i.e.: macrophages, lymphocytes and natural killer (NK) cells of adult (33+/-1 week old) and aged (75+/-1 week old) female Swiss mice. Two groups of animals, adult and aged mice, fed standard diet were used as controls. The results show that the ingestion of 0.1% doses of thiols improves, in the adult mice, several immune functions such as the chemotaxis capacity of both macrophages and lymphocytes, the phagocytosis of macrophages, the lymphoproliferative response to the mitogen Con A and the NK activity. Moreover, no change was observed in adherence capacity of immune cells, and superoxide production was decreased. By contrast, in aged mice the ingestion of these amounts of antioxidants did not change the immune functions studied with the exception of NK activity, which was stimulated. The ingestion of 0.3% of antioxidants by adult mice only increased some immune functions such as adherence and superoxide production, which are markers of oxidative stress. Other functions such as chemotaxis or lymphoproliferative response decreased. However, the ingestion of these very high amounts of thiols by aged animals increased the phagocytosis, the NK activity and specially the lymphoproliferative response to the mitogen, a function that is very depressed with aging.

Acetylcysteine↗
PubMed2001

Helminth parasites of the eurasian badger (Meles meles L.) in Spain: a biogeographic approach.

Eighty-five Eurasian badgers, Meles meles (Linnaeus, 1758), from four mainland biogeographic Spanish areas were analysed for helminths. Seventeen helminth species were found: Brachylaima sp., Euparyphium melis and Euryhelmis squamula (Trematoda), Atriotaenia incisa and Mesocestoides sp. (Cestoda) and Aelurostrongylus pridhami, Angiostrongylus vasorum, Aonchotheca putorii, Crenosoma melesi, Mastophorus muris, Molineus patens, Pearsonema plica, Physaloptera sibirica, Strongyloides sp., Trichinella sp., Uncinaria criniformis and Vigisospirura potekhina hugoti (Nematoda). In the Mediterranean area, Aonchotheca putorii, M. patens, Strongyloides sp., and U. criniformis were more prevalent in the occidental part, whereas Atriotaenia incisa and Mesocestoides sp. cestodes showed higher values on the continental slope. Metastrongyloid species (Aelurostrongylus pridhami, Angiostrongylus vasorum and Crenosoma melesi) were only detected in the occidental Mediterranean area. In contrast, spirurid species (Mastophorus muris and Vigisospirura potekhina hugoti) were almost restricted to the continental Mediterranean area. Helminthological differences between areas may result from the badger diet, abiotic factors and biocenosis present in each biogeographic area.

Animals↗
PubMed2001

[Autoimmune hepatitis with prolonged IGM antibodies to HAV. Are serological markers reliable in ruling out a diagnosis of autoimmune hepatitis?].

We present the case of a 44-year-old woman who was referred to us for jaundice, choluria and acholia. Review of the patient's clinical history revealed that tests for hepatitis A virus (HAV) IgM antibody had been positive 4 and 2 years previously and continued to be so. The patient showed a score of 16 in the International Autoimmune Hepatitis Group's system when the HAV marker was not taken into account and a score of 13 when this marker was taken into account. The persistence of this viral marker for so many years in such patients is probably associated with polyclonal hypergammaglobulinemia. Consequently, we believe that the inclusion of this antibody as a negative datum in the diagnosis of autoimmune virus should be viewed with caution.

Adult↗
PubMed2001

Nutrition and ageing.

The reviewed literature indicates that, even in industrialised countries, the nutrition of mature and aged subjects is often inadequate (because of deficiency or excess), which may lead to premature or pathological senescence. Recent nutritional research on ageing laboratory animals shows that dietary restriction may be the most effective procedure to achieve a long and disease-free life span, probably owing to a better protection against mitochondria-linked oxygen stress. Likewise, the experimental and clinical work from many laboratories, including our own, indicates that age-dependent changes in the cardiovascular and immune systems are linked to oxygen stress and that an adequate intake of dietary antioxidants may protect those systems against chronic degenerative syndromes in the physiopathology of which reactive oxygen species (ROS) play a key role. The extant data indicate that the antioxidant vitamins C and E are centrally involved in defending the above two systems against ROS attack. Moreover, recent research suggests that the glutathione-related thiolic antioxidants, thiazolidine carboxylic acid (thioproline) and N-acetylcysteine, as well as the phenolic liposoluble 'co-antioxidants' of Curcuma longa, may have a significant protective effect against age-related atherogenesis and immune dysfunction. Key messages from this paper are the following. (1) It is generally accepted that oxygen free radicals released in metabolic reactions play a key role in the physiopathology of 'normal ageing' and of many age-related degenerative diseases. (2) Consumption of adequate levels of antioxidants in the diet is essential in order to preserve health in old age. (3) A certain degree of protection against atherogenesis and immune dysfunction may be achieved by preventing vitamin E deficiency and an excessive oxidation of the glutathione-supported thiol pool.

Aged↗
PubMed2001

Role of Helicobacter pylori infection and its eradication in patients with subclinical hepatic encephalopathy.

AIMS: Helicobacter pylori infection in cirrhotic patients has been associated with episodes of hepatic encephalopathy (HE), although conclusive data are still lacking. This prospective study has evaluated the prevalence of H. pylori infection in 37 patients with advanced cirrhosis of the liver and subclinical hepatic encephalopathy (SHE), diagnosed by changes in psychometric tests and/or electrophysiological tests, as well as the repercussion of H. pylori eradication on ammonaemia and the evolution of this disorder. RESULTS: A positive result for H. pylori infection was obtained in 22/37 (59%) patients. Initial fasting blood levels of ammonia were high in both groups. Infected and non-infected patients showed similar levels (62.05 mmol/l v. 62.5 mmol/l), which were lowered by the standard diet, although statistical significance was only reached in the infected patient group (53.05 +/- 26 mmol/l; P < 0.05). Infection was eradicated in 19 patients, but no reduction of blood levels of ammonia was observed after H. pylori eradication among infected patients (52.37 +/- 29 mmol/l). No change has been found in either group after the administration of diet or antimicrobials with regard to psychometric and/or electrophysiological tests. CONCLUSIONS: H. pylori infection does not contribute significantly to high blood levels of ammonia in patients with advanced cirrhosis and SHE. Likewise, H. pylori eradication does not induce any improvement in the psychometric and/or electrophysiological tests used to define SHE.

Adult↗
PubMed2001

Helminths in the wolf, Canis lupus, from north-western Spain.

Fifteen helminth species were collected from 47 wolves (Canis lupus ) which were surveyed from 1993 to 1999 in northwestern Spain. These included the trematode Alaria alata (2.1%); the cestodes Taenia hydatigena (44.7%), T. multiceps (29.8%), T. serialis (2.1%), Dipylidium caninum (6.4%) and Mesocestoides sp. aff. litteratus (4.2%); and the nematodes Pearsonema plica (7.4%), Trichuris vulpis (10.6%), Trichinella britovi (12.8%), Ancylostoma caninum (8.5%), Uncinaria stenocephala (51.1%), Toxocara canis (6.4%) Toxascaris leonina (4.2%), Angiostrongylus vasorum (2.1%) and Dirofilaria immitis (2.1%). Only two wolves were not infected. A single infection occurred in 28.9% of the cases, but the commonest infracommunity (31.1%) involved three species. The helminths Alaria alata, Taenia hydatigena, Mesocestoides sp. aff. litteratus, P. plica, Trichuris vulpis, and Ancylostoma caninum parasitizing C. lupus are reported for the first time in Spain. Taenia serialis and D. immitis are reported for the first time in wolves in Europe. Angiostrongylus vasorum represents a new host record for wolves. The helminth fauna of Spanish wolves is compared with that of other European wolf populations. Some epidemiological considerations of the helminth fauna of wolves in Spain and the health risk to humans are also discussed.

Animals↗
PubMed2000

An hydroalcoholic extract of curcuma longa lowers the apo B/apo A ratio. Implications for atherogenesis prevention.

It is generally accepted that free-radical induced blood lipid peroxidation and especially peroxidized LDL play a central role in the pathogenesis of atherosclerosis and related cardiovascular disease. Moreover, recent research highlights the key contribution of apolipoprotein B (apo B) to atherogenesis as the main inductor of one of its earlier steps, i.e. macrophage proliferation. This has led us to investigate the apo B response to a very effective phenolic lipid-antioxidant, namely an hydroalcoholic extract of Curcuma longa, which according to our previous work does not show any toxic effects and decreases the levels of blood lipid peroxides, oxidized lipoproteins and fibrinogen. The present study shows that a daily oral administration of the extract decreases significantly the LDL and apo B and increases the HDL and apo A of healthy subjects. This and recent data on the increased anti-atherogenic action of the physiological antioxidant tocopherol in the presence of phenolic co-antioxidants (which eliminate the tocopheroxyl radical), justifies planned clinical research to test the usefulness of the curcuma extract as a co-antioxidant complement to standard treatments to prevent or retard atherosclerosis.

Adult↗
PubMed2000

An in vitro model of ischemic-like stress in retinal pigmented epithelium cells: protective effects of antioxidants.

We have developed a model of in vitro cell oxidative stress in bovine retinal pigment epithelium cells exposed to a ischemia-like condition obtained by interference with glucose utilization through both oxidative phosphorylation and glycolysis. This resulted in a statistically significant decrease of the intracellular ATP levels, which reflects a bioenergetic decline similar to that associated with mitochondrial damage or loss in normal post-mitotic cells aging in vivo. This new model of cellular oxygen stress seems adequate for investigation of the protective action of antioxidants, in agreement with our finding of a statistically significant increase in the ATP levels over the values of the non-treated samples in retinal pigment epithelium cells exposed to the above oxygen stress in medium supplemented with 300 microM vitamin C or 10 mM N-acetylcysteine.

Adenosine Triphosphate↗
PubMed2000

Ultrastructure of spermiogenesis and the spermatozoon of Opecoeloides furcatus (Trematoda, Digenea, Opecoelidae), a parasite of Mullus barbatus (Pisces, Teleostei).

Spermiogenesis and mature spermatozoa of Opecoeloides furcatus (Digenea, Opecoelidae) are described by means of transmission electron microscopy. Spermiogenesis in this fluke matches the general pattern of digenetic trematodes. Striated rootlets associated with the two centrioles and an intercentriolar body are present in the differentiation zone. Flagellar rotation of two flagella and their proximodistal fusion with a median cytoplasmic process also characterize the spermiogenesis of O. furcatus. Nevertheless, asynchronicity is reported for the proximodistal fusion of the two flagella. Mature spermatozoa of O. furcatus are filiform, tapering at both ends and they present all the characteristic features found in the Digenea gamete: two flagella, mitochondrion, nucleus and two bundles of parallel cortical microtubules. Nevertheless several peculiarities distinguish the mature spermatozoon of O. furcatus from the gamete of other digenetic trematodes.

Animals↗
PubMed2000

Ultrastructural study of spermiogenesis and the spermatozoon in Catenotaenia pusilla, an intestinal parasite of Mus musculus.

The ultrastructure of spermiogenesis and the mature spermatozoon in Catenotaenia pusilla (Cestoda: Catenotaeniidae) is described. Spermiogenesis is characterized by the presence of a single axoneme which grows on the outside of a cytoplasmic extension at an angle of 45 degrees. Flagellar rotation and proximodistal fusion are produced in this process. The centrioles lack striated roots and an intercentriolar body. In the mature spermatozoon four different regions are described. The anterior extremity is capped by an apical cone and presents two helical crest-like bodies of unequal length. The axoneme, of the 9 + '1' pattern of the Trepaxonemata, presents a periaxonemal sheath. The cortical microtubules form a spiral pattern at an angle of about 40 degrees to the hypothetical spermatozoon axis. The nucleus is kidney- to horseshoe-shaped in cross section. Granules and proteinaceus walls are not observed in the spermatozoon of C. pusilla.

Animals↗
PubMed2000

[Idiopathic chronic pancreatitis (with diffuse stenosis of Wirsung's duct) in ulcerative colitis].

We describe a case of chronic idiopathic pancreatitis associated with ulcerative colitis. Pancreatitis is a rare extra-intestinal manifestations of inflammatory bowel disease. Chronic idiopathic pancreatitis associated with ulcerative colitis are usually painless, without calcification, with stricture of the main pancreatic duct and with severe exocrine pancreatic insufficiency.

Chronic Disease↗
PubMed1999

Ultrastructure of spermiogenesis and the spermatozoon of Mesocestoides litteratus (Cestoda, Mesocestoididae).

This paper constitutes the first ultrastructural study of spermiogenesis and the spermatozoon of a cestode belonging to the family Mesocestoididae, Mesocestoides litteratus. Spermiogenesis in M. litteratus is characterised by a flagellar rotation and a proximodistal fusion. The zone of differentiation presents striated roots associated with the centrioles and also an intercentriolar body. The most interesting ultrastructural feature found in the mature spermatozoon of M. litteratus is the presence of parallel cortical microtubules. The spermatozoon also exhibits a single crest-like body and granules of glycogen. The pattern of spermiogenesis and the parallel position of cortical microtubules reveal the lack of concordance between M. litteratus and cyclophyllidean species studied to date in spermiogenesis and in the ultrastructural organisation of spermatozoon. This study provides new spermatological data and calls into question the validity of the current systematic position of mesocestoidids.

Animals↗