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M Pascual

Publications and source records attributed to M Pascual.

At least 19 recordsLinked to original sources
PubMed2006

Malaria resurgence in the East African highlands: temperature trends revisited.

The incidence of malaria in the East African highlands has increased since the end of the 1970s. The role of climate change in the exacerbation of the disease has been controversial, and the specific influence of rising temperature (warming) has been highly debated following a previous study reporting no evidence to support a trend in temperature. We revisit this result using the same temperature data, now updated to the present from 1950 to 2002 for four high-altitude sites in East Africa where malaria has become a serious public health problem. With both nonparametric and parametric statistical analyses, we find evidence for a significant warming trend at all sites. To assess the biological significance of this trend, we drive a dynamical model for the population dynamics of the mosquito vector with the temperature time series and the corresponding detrended versions. This approach suggests that the observed temperature changes would be significantly amplified by the mosquito population dynamics with a difference in the biological response at least 1 order of magnitude larger than that in the environmental variable. Our results emphasize the importance of considering not just the statistical significance of climate trends but also their biological implications with dynamical models.

Africa, Eastern↗
PubMed2006

Population structure within and between subspecies of the Mediterranean triplefin fish Tripterygion delaisi revealed by highly polymorphic microsatellite loci.

Although F(ST) values are widely used to elucidate population relationships, in some cases, when employing highly polymorphic loci, they should be regarded with caution, particularly when subspecies are under consideration. Tripterygion delaisi presents two subspecies that were investigated here, using 10 microsatellite loci. A Bayesian approach allowed us to clearly identify both subspecies as two different evolutionary significant units. However, low F(ST) values were found between subspecies as a consequence of the large number of alleles per locus, while homoplasy could be disregarded as indicated by the standardized genetic distance G'(ST). Heterozygosity saturation was observed in highly polymorphic loci containing more than 15 alleles, and this threshold was used to define two loci pools. The less variable loci pool revealed higher genetic variance between subspecies, while the more variable pool showed higher genetic variance between populations. Furthermore, higher differentiation was also observed between populations using G'(ST) with the more variable loci. Nonetheless, a more reliable population structure within subspecies was obtained when all loci were included in the analyses. In T. d. xanthosoma, isolation by distance was detected between the eight analysed populations, and six genetically homogeneous clusters were inferred by Bayesian analyses that are in accordance with F(ST) values. The neighbourhood-size method also indicated rather small dispersal capabilities. In conclusion, in fish with limited adult and larval dispersal capabilities, continuous rocky habitat seems to allow contact between populations and prevent genetic differentiation, while large discontinuities of sand or deep-water channels seems to reduce gene flow.

Alleles↗
PubMed2005

Lead-induced catalase activity differentially modulates behaviors induced by short-chain alcohols.

Acute lead administration produces a transient increase in brain catalase activity. This effect of lead has been used to assess the involvement of brain ethanol metabolism, and therefore centrally formed acetaldehyde, in the behavioral actions of ethanol. In mice, catalase is involved in ethanol and methanol metabolism, but not in the metabolism of other alcohols such as 1-propanol or tert-butanol. In the present study, we assessed the specificity of the effects of lead acetate on catalase-mediated metabolism of alcohols, and the ability of lead to modulate the locomotion and loss of the righting reflex (LRR) induced by 4 different short-chain alcohols. Animals were pretreated i.p. with lead acetate (100 mg/kg) or saline, and 7 days later were injected i.p. with ethanol (2.5 or 4.5 g/kg), methanol (2.5 or 6.0 g/kg), 1-propanol (0.5 or 2.5 g/kg) or tert-butanol (0.5 or 2.0 g/kg) for locomotion and LRR, respectively. Locomotion induced by ethanol was significantly potentiated in lead-treated mice, while methanol-induced locomotion was reduced by lead treatment. The loss of righting reflex induced by ethanol was shorter in lead-treated mice, and lead produced the opposite effect in methanol-treated mice. There was no effect of lead on 1-propanol or tert-butanol-induced behaviors. Lead treatment was effective in inducing catalase activity and protein both in liver and brain. These results support the hypothesis that the effects of lead treatment on ethanol-induced behaviors are related to changes in catalase activity, rather than some nonspecific effect that generalizes to all alcohols.

Alcohols↗
PubMed2005

[Surgical options for terminal heart failure].

Terminal heart failure can be the cause or the result of major dysfunctions of the organisms. Although, the outcome of the natural history is the same in both situations, it is of prime importance to differentiate the two, as only heart failure as the primary cause allows for successful mechanical circulatory support as bridge to transplantation or towards recovery. Various objective parameters allow for the establishment of the diagnosis of terminal heart failure despite optimal medical treatment. A cardiac index <2.0 l/min, and a mixed venous oxygen saturation <60%, in combination with progressive renal failure, should trigger a diagnostic work-up in order to identify cardiac defects that can be corrected or to list the patient for transplantation with/without mechanical circulatory support.

Assisted Circulation↗
PubMed2005

Demand-feeding rhythms and feeding-entrainment of locomotor activity rhythms in tench (Tinca tinca).

Tench (Tinca tinca) has been described as a strictly nocturnal species whose locomotor activity rhythms, albeit strongly synchronised by light, have an endogenous nature. Aside from light, a number of other environmental factors, such as mealtime, can act as circadian system synchronisers in fish; however, there is a scarcity of information on tench feeding rhythms. This study describes daily self-feeding rhythms in tench, and analyses the role of feeding time on synchronisation of locomotor activity rhythms. Tench were able to operate string sensor-activated self-feeders, and they displayed a strictly nocturnal behavior, both under indoor and outdoor conditions. Locomotor activity remained strictly nocturnal irrespective of whether tench were fed only during the scotophase (D-feeding) or the photophase (L-feeding). However, no statistically significant differences were detected between both groups in terms of food intake or growth performance. Furthermore, unlike L-feeding, D-feeding elicited a clear anticipatory activity (FAA). When tench were given the possibility of feeding at both times of the day, they showed a clear preference for D-feeding. Finally, in fish exposed to constant darkness (DD), feeding time acted as a true zeitgeber and FAA was observed. When animals were fasted under DD conditions, locomotor activity free-run and 6 out of 12 individuals yielded significant results in the periodogram analysis. Under DD, fish resynchronised when regular food was resumed, with some tench displaying FAA. The obtained results indicated the existence of a feeding-entrainable oscillator (FEO) in tench.

Animals↗
PubMed2005

Treatment of cytomegalovirus infection or disease in solid organ transplant recipients with valganciclovir.

Valganciclovir (VGC) has proved efficacious and safe for the prophylaxis against cytomegalovirus (CMV) in high-risk transplant recipients and for the treatment of CMV retinitis in AIDS patients. We used VGC for the treatment of CMV infection (viremia without symptoms) or disease (CMV syndrome or tissue-invasive disease) in kidney, heart, and lung transplant recipients. Fourteen transplant recipients were treated: five for asymptomatic CMV infection and nine for CMV disease. VGC was administered in doses adjusted to renal function for 4 to 12 weeks (induction and maintenance therapy). Clinically, all nine patients with CMV disease responded to treatment. Microbiologically, treatment with VGC turned blood culture negative for CMV within 2 weeks in all patients and was associated with a > or =2 log decrease in blood CMV DNA within 3 weeks in 8 of 8 tested patients. With a follow-up of 6 months (n = 12 patients), asymptomatic recurrent CMV viremia was noted in five cases, and CMV syndrome noted in one case (all cases in the first 2 months after the end of treatment). VGC was clinically well tolerated in all patients; however, laboratory abnormalities occurred in three cases (mild increase in transaminases, thrombocytopenia, and pancytopenia). This preliminary experience strongly suggests that therapy with VGC is effective against CMV in organ transplant recipients; however, the exact duration of therapy remains to be determined: a longer course may be necessary to prevent early recurrence.

Antiviral Agents↗
PubMed2005

Donors with positive blood culture: could they transmit infections to the recipients?

A retrospective analysis of data from January 1996 to June 2004 was performed to evaluate the transmission of bacterial infections from organ donors to recipients. Donors were classified according to blood culture results: group 1 with negative blood culture (n = 216), and group 2 with positive blood cultures (n = 52). The age, cause of death, temperature, leukocytes, and number of organs procured were similar in both groups. Donors of group 2 had significantly more days in the intensive care unit (ICU): group 1 (3.14 +/- 3) versus group 2 (4.39 +/- 3.38 days P = .038). Fifty-one percent of group 1 and 52% of group 2 received antibiotic treatment, in most cases because of the suspected presence of a respiratory infection. In 22 donors the organisms that yielded in the blood culture were considered potentially pathogenic/contaminants (subgroup 2A) and in 30 donors the organisms were considered pathogenic (subgroup 2B). The demographic profiles of these two subgroups were similar. During the first month after transplantation, kidney and liver recipients were closely monitored. Recipients received wide-spectrum antimicrobial prophylaxis. Ten of 61 renal recipients developed infectious diseases. In nine cases (four in subgroup 2A and five in subgroup 2B) there were urinary infections. One recipient of subgroup 2B developed prostatitis. Six of 34 hepatic recipients developed infectious diseases. Four of the six cases (four in group 2A and five in group 2B) developed catheter infections and two cases of peritoneal infections. We could not find any case where a bacterial blood isolate from a donor matched a positive culture in the corresponding recipient. A longer stay of a donor in the ICU resulted in the more pronounced growth of organisms in blood cultures, as expected. In our experience, organs obtained from a donor with a positive blood culture may be transplanted safely, probably due to the low virulence of the organisms as well as the polymicrobial therapy routinely given to the recipients.

Anti-Bacterial Agents↗
PubMed2005

Multipotent progenitor cells isolated from adult human pancreatic tissue.

The supply of islet cells is a limiting factor for the widespread application of islet transplantation of type-1 diabetes. Islets constitute 1% to 2% of pancreatic tissue, leaving approximately 98% as discard after islet isolation and purification. In this report we present our data on the isolation of multipotent progenitor cells from discarded adult human pancreatic tissue. The collected cells from discarded nonislet fractions, after enzymatic digestion and gradient purification of islets, were dissociated for suspension culture in a serum-free medium. The cell clusters grown to a size of 100 to 150 mum contained cells staining for stage-specific embryonic antigens, but not insulin or C-peptide. To direct cell differentiation toward islets, clusters were recultured in a pancreatic differentiation medium. Insulin and C-peptide-positive cells by immunocytochemistry appeared within a week, reaching over 10% of the cell population. Glucagon and somatostatin-positive cells were also detected. The cell clusters were found to secrete insulin in response to glucose stimulation. Cells from the same clusters also had the capacity for differentiation into neural cells, as documented by staining for neural and glial cell markers when cultured as monolayers in media containing neurotrophic factors. These data suggest that multipotent pancreatic progenitor cells exist within the human pancreatic tissue that is typically discarded during islet isolation procedures. These adult progenitor cells can be successfully differentiated into insulin-producing cells, and thus they have the potential for treatment of type-1 diabetes mellitus.

Adult↗
PubMed2005

Urological complications in renal transplantation from cadaveric donor grafts: a retrospective analysis of 20 years.

INTRODUCTION: This study is a retrospective analysis of ureteral complications and their management from a monocenter series of 277 consecutive renal transplantations. MATERIALS AND METHODS: From September 1979 to June 1999, 277 renal transplantations (cadaveric origin) were performed in 241 patients. The ureter from the kidney graft was inserted into the bladder according to the technique of extravesical implantation described by Lich-Gregoir and Campos-Freire. The study analyzed the time of occurrence and the type of complications observed. The different procedures to restore the transplanted urinary tract are presented. RESULTS: Complications occurred in 43/277 renal transplantations (15.5%). Anastomotic urine leakage or ureteral stricture were the most frequent. The time to appearance of these complications was either short (<1 month) or late (>1 month) in a similar number of cases. Most cases were managed surgically: 33/43 cases (76.7%). The most frequent surgical repair was ureterovesical reimplantation (n=13), followed by: ureteroureteral end-to-end anastomosis (native ureter-ureter transplant, n=5); pyeloureteral anastomosis (native ureter-renal pelvis transplant, n=5); simple revision of ureterovesical implantation (n=4); resection and end-to-end anastomosis of the transplant ureter (n=2); calico-vesicostomy (graft-bladder, n=1); implantation according to Boari (n=1); pyelovesicostomy with bipartition of bladder (n=1), and pyeloileocystoplasty with detubularized ileal graft (n=1). No deaths related to any of the urological complications were reported. However, 2 consecutive vesico-renal refluxes led to the loss of the kidney graft in the long-term. CONCLUSION: The rate of complications observed in this retrospective analysis is similar to the experience of other studies, ranging from 2 to 20%. If the classical extravesical ureteral bladder implantation is to remain an attractive technique due to its simplicity, the surgical team at the training center should be aware of all the means to prevent any ureteral complications, such as the choice of another implantation technique and/or insertion of a transient ureteral stent.

Adolescent↗
PubMed2005

Sirolimus-induced acneiform eruption.

Sirolimus is a new immunosuppressive agent used to prevent rejection in renal allograft recipients in order to reduce the need of potentially nephrotoxic calcineurin inhibitors (cyclosporine, tacrolimus). The cutaneous side effects of sirolimus are not well known and they may have been underestimated. We report 2 cases of follicular acneiform eruptions induced by sirolimus in renal allograft recipients. This dermatologic complication was severe and difficult to treat, and resolved only after discontinuation of sirolimus.

Acneiform Eruptions↗
PubMed2004

Strong population structure in the marine sponge Crambe crambe (Poecilosclerida) as revealed by microsatellite markers.

Different categories of molecular markers have been used so far to study the population structure of sponges. However, these markers often did not have the resolution power to address precisely questions on structuring processes, especially at the intrapopulational level. In this study we show that microsatellites fulfil these expectations, allowing a fine description of population structure at different geographical scales in the marine sponge Crambe crambe. Specimens were collected in 11 locations, representing most of the Atlanto-Mediterranean range of the species, and were analysed at six loci. As expected for a sessile invertebrate with lecitotrophic larvae, high levels of between-population structure were found (FST = 0.18) and a significant isolation-by-distance pattern was observed. A strong genetic structure was also found within sampled sites (FIS = 0.21) that may be explained by several factors including inbreeding, selfing and the Wahlund effect. In spite of a sampling design planned to avoid the sampling of clones, genotypically identical individuals for the six loci were found in some locations. The significance of these potential clones is discussed and their effect on the observed pattern of population structure assessed. Patterns of allelic distribution within populations suggest the possibility of a recent colonization of the Atlantic range from the Mediterranean Sea.

Animals↗
PubMed2004

Phylogeography and speciation of colour morphs in the colonial ascidian Pseudodistoma crucigaster.

Variation in pigmentation is common in marine invertebrates, although few studies have shown the existence of genetic differentiation of chromatic forms in these organisms. We studied the genetic structure of a colonial ascidian with populations of different colour morphs in the northwestern Mediterranean. A fragment of the c oxidase subunit 1 (COI) mitochondrial gene was sequenced in seven populations of Pseudodistoma crucigaster belonging to three different colour morphs (orange, yellow and grey). Maximum likelihood analyses showed two well-supported clades separating the orange morph from the yellow-grey morphotypes. Genetic divergence between these clades was 2.12%, and gamma(ST) values between populations of the two clades were high (average 0.936), pointing to genetic isolation. Nested clade and coalescence analyses suggest that a past fragmentation event may explain the phylogeographical origin of these two clades. Non-neutral mtDNA evolution is observed in our data when comparing the two clades, showing a significant excess of nonsynonymous polymorphism within the yellow-grey morphotype using the McDonald-Kreitman test, which is interpreted as further support of reproductive isolation. We conclude that the two clades might represent separate species. We compare the population genetic differentiation found with that estimated for other colonial and solitary ascidian species, and relate it to larval dispersal capabilities and other life-history traits.

Animals↗
PubMed2003

A poly(ADP-ribose) polymerase haplotype spanning the promoter region confers susceptibility to rheumatoid arthritis.

OBJECTIVE: To investigate the association of the poly(ADP-ribose) polymerase 1 (PARP-1) gene promoter polymorphism with rheumatoid arthritis (RA) predisposition. METHODS: An association study with 213 Spanish RA patients and 242 healthy subjects was carried out to investigate the association of all known PARP-1 gene promoter polymorphisms, i.e., a CA microsatellite repeat, a poly(A)(n), and 3 single point mutations (C410T, C1362T, and G1672A), with disease susceptibility. Additionally, we analyzed the distribution of PARP-1 polymorphisms in 58 Spanish families with 1 or more affected members. RESULTS: Upon complete genotyping of the panel of 455 samples, strong linkage disequilibrium was observed among the 5 PARP-1 polymorphisms. Only 2 PARP-1 haplotypes were detected: haplotype A (410T-[A](10)-[CA](10-12)-1362C, which includes short PARP-1 CA alleles) and haplotype B (410C-[A](11)-[CA](13-20)-1362T, always paired with long PARP-1 CA variants). Regarding the G1672A variation, although linkage disequilibrium was detected, it did not seem to be part of the conserved haplotypes described. Haplotype B was statistically overrepresented in the RA patient group compared with the healthy subjects (odds ratio 1.42, 95% confidence interval 1.06-1.91, P = 0.019). In addition, a significant dose effect of PARP-1 haplotype carriage on disease predisposition was observed. Of note, within haplotype B, the PARP-1 CA 97-bp allele was found to be the RA-predisposing marker (odds ratio 2.17, 95% confidence interval 1.27-3.72, P = 0.003, corrected P < 0.05). CONCLUSION: Our results demonstrate the existence of 2 unique PARP-1 haplotypes in the Spanish population and provide the first evidence that PARP-1 haplotypes play a role in susceptibility to RA.

Arthritis, Rheumatoid↗
PubMed2003

Importance of tumoral markers in donors: study of prostate-specific antigen.

UNLABELLED: We established a protocol to determine the serum prostate-specific antigen (PSA) in male donors of 50 years or older, and to histologically examine the prostate glands. From January 1997 to December 2002 we analysed serum PSA in 51 cases, of which it was normal in 34 and high in 17. Prostate glands were examined histologically in 13 of the high PSA cases. Donors were classified according to the PSA level and histology: donors with high PSA values and adenocarcinoma or high-grade PIN (group A, n=6); donors with elevated PSA but no malignancy (group B, n=7); and donors with normal PSA (group C, n=34). The ages, days in hospital, and causes of death were similar among the 3 groups. The levels of PSA were significantly higher among group A than group B or group C, but were similar between group B and C. The list of transplanted organs is as follows: 5 organs of group A; 8 organs of group B; and 59 organs of group C. CONCLUSIONS: High PSA levels seem show 2 patterns: (1) small increases of PSA related to donors with no prostate cancer, and (2) high levels of PSA related to the presence of prostate cancer, as is the case in the general population. The incidence of prostate cancer in overall male donors was 3.1%. Due to this high incidence, we believe it is important to determine PSA levels to diagnose prostate cancer in older donors. A separate consideration is what to do with the organs of those donors.

Adenocarcinoma↗
PubMed2003

Genetic polymorphisms in Spanish rheumatoid arthritis patients: an association and linkage study.

HLA polymorphism accounts only for approximately one-third of the genetic predisposition to rheumatoid arthritis (RA). To investigate the role of other loci in the susceptibility to RA, we have performed an analysis of several polymorphisms in genes of immune-related function: IL-10 -1082, -819, -592 promoter single nucleotide polymorphisms (SNPs), IL-10G and IL-10R microsatellites, IL-6 -622 promoter SNP, FcgammaRIIIA Val/Phe-158 polymorphism, IL-1 receptor antagonist VNTR, and the IKBL+738 T/C mutation. The analysis has been performed on a case-control study and also on RA trios. IL-10G12 was found to be associated with RA in the case-control study (18% in RA patients vs 9% in controls: P=0.001; pc<0.05). This allele was also more often transmitted than not transmitted (10 vs 5). No other allele in the present study is found to be associated to RA. Our data suggest that most of the loci studied play no major role in the susceptibility to RA, the IL-10 gene being the sole exception.

Arthritis, Rheumatoid↗
PubMed2003

Association of MICA-A5.1 allele with susceptibility to celiac disease in a family study.

OBJECTIVE: The aim of this study was to analyze the role of the major histocompatibility complex class I chain-related gene A (MICA) transmembrane polymorphism in celiac disease (CD) susceptibility. METHODS: Sixty-one celiac Spanish families were genotyped for MICA transmembrane polymorphism by a polymerase chain reaction method combined with fluorescent technology. A transmission disequilibrium test was performed to investigate the preferential transmission of MICA alleles to the affected offspring. RESULTS: The MICA A5.1 allele was shown to be significantly transmitted to the affected siblings. This association was independent of the CD-predisposing DQ2 haplotype. Additionally, we classified our celiac families into typical and atypical groups as we found a significant association with MICA A5.1 in typical celiac families. There was also an association tendency with atypical families. CONCLUSIONS: Our data suggest that the MICA A5.1 allele is associated with CD development independently of DQ2-extended haplotype and clinical forms of CD.

Alleles↗