Search PubMed⌕ Search

Biomedical subjects

M A Valero

Publications and source records attributed to M A Valero.

At least 19 recordsLinked to original sources

High risk of bacterobilia in advanced experimental chronic fasciolosis.

Fasciolosis is recognized as an important human disease. Wistar rats experimentally infected with Fasciola hepatica were examined using data obtained in the advanced chronic state of the disease (200, 300 and 400 days post-infection, dpi). Pigment stones (PS) and bile specimens were collected. The same procedure was applied in control rats. Liver tests were determined using stored serum samples. Bacteriological bile culture revealed viable bacteria (Escherichia coli, 45% of cases, Enterococcus faecalis, 45% and Klebsiella pneumoniae, 10%). The presence of bacterobilia was associated with liver serum enzymes, including aspartate aminotransferase (AST or SGOT), alanine aminotransferase (ALT or SGPT), alkaline phosphatase (AP) and total bilirubin levels. Multivariate analysis suggested an association between bacterobilia and the following factors: duration of parasitic infection and intensity of parasitic infection supported the impression that the obstruction caused by advanced chronic fasciolosis in the rat may be related to biliary sepsis. Extrapolation to human infection in fasciolosis hyperendemic areas is discussed. In conclusion, the results of the rodent model should lead to a reconsideration of treatment features in human disease, i.e. therapeutic strategies should not only include a parasitic treatment but also consider the possibility of bacterial co-infection.

Animals↗

Phenotypic analysis of adults of Fasciola hepatica, Fasciola gigantica and intermediate forms from the endemic region of Gilan, Iran.

Fascioliasis is an important human and animal disease caused by Fasciola hepatica and Fasciola gigantica. In Iran, the distribution of these two species overlaps in most areas, including the northern human endemic province of Gilan where both fasciolids are simultaneously found in individual cattle and buffaloes. A phenotypic study of fasciolid adult flukes from naturally infected bovines from Gilan was carried out by means of an exhaustive morphometric analysis using traditional microscopic measurements and an allometric model. The Iranian fasciolids were compared to F. hepatica and F. gigantica standard populations, i.e. from geographical areas where both species do not co-exist (Bolivia and Burkina Faso, respectively). Although morphometric values somewhat overlapped, there were clear differences in allometric growth. The allometric function was adjusted to 25 pairs of variables. Results obtained revealed that Iranian F. hepatica-like specimens are larger than the F. hepatica standard and Iranian F. gigantica-like specimens are longer and narrower than the F. gigantica standard, but with smaller body area. Measurements which permit a specific differentiation in allopatric populations (distance between ventral sucker and posterior end of the body; ratio between body length and body width) overlap in the specimens from Gilan, thus proving the presence of intermediate forms. When compared to the standard populations, the different Iranian fasciolid morphs show greater differences in F. gigantica-like specimens than in F. hepatica-like specimens. This study shows that simple, traditional microscopic measurements may be sufficient for the morphometric characterisation of fasciolids, even in areas where intermediate forms are present.

Animals↗

Crowding effect on adult growth, pre-patent period and egg shedding of Fasciola hepatica.

Fascioliasis pathogenesis depends on fluke burden. In human hyperendemic zones, individual infection intensities reach very high levels and the majority of infected subjects should be in the advanced chronic phase. The rat model offers a useful approach for pathological research in the advanced chronic period. The influence of infection intensity per rat on fluke development, pre-patent period and egg shedding (eggs/g faeces/worm) was analysed in 3 groups (I: 1-3 worms/rat; II: 4-6; III: 7-9). Ontogenetic trajectories of fluke body measures followed a logistic model. Results showed that when the burden increases, the maximum values of fluke measures decrease. The crowding effect is manifest when fluke measures approximate their maximums in the advanced chronic stage. The pre-patent period and egg production decrease when the burden increases. This means that measurements of eggs per gramme of faeces tend to underestimate the fluke burden. The present study demonstrates how to quantify the fascioliasis experimental rat model crowding effect on adult growth, pre-patent period and egg production. This quantification may be of great interest in epidemiological studies and in experimental research on the in vivo actions of different anthelminthic drugs and vaccines, pathology, immunology and resistance studies.

Animals↗

Phenotypic comparison of allopatric populations of Fasciola hepatica and Fasciola gigantica from European and African bovines using a computer image analysis system (CIAS).

The quantification of the different sizes and shapes of Fasciola hepatica and Fasciola gigantica from bovines has been achieved for the first time in natural allopatric populations. Linear measurements, areas and ratios of gravid adults and eggs of F. hepatica (from France and Spain) and F. gigantica (from Burkina Faso) were analysed using a computer image analysis system and an allometric model: (y2m - y2)/y2 = c[(y1m - y1)/y1](b), where y1 = body area or body length, y2 = one of the measurements analysed, y1m, y2m = maximum values towards which y1 and y2, respectively, tend and c, b = constants. All the measurements overlap in the two fasciolids, apart from the distance between the ventral sucker and the posterior end of the body, body roundness and body length/body width ratio. The results obtained may be useful in Fasciola species identification in countries where both species coexist.

Africa↗

Fascioliasis and other plant-borne trematode zoonoses.

Fascioliasis and other food-borne trematodiases are included in the list of important helminthiases with a great impact on human development. Six plant-borne trematode species have been found to affect humans: Fasciola hepatica, Fasciola gigantica and Fasciolopsis buski (Fasciolidae), Gastrodiscoides hominis (Gastrodiscidae), Watsonius watsoni and Fischoederius elongatus (Paramphistomidae). Whereas F. hepatica and F. gigantica are hepatic, the other four species are intestinal parasites. The fasciolids and the gastrodiscid cause important zoonoses distributed throughout many countries, while W. watsoni and F. elongatus have been only accidentally detected in humans. Present climate and global changes appear to increasingly affect snail-borne helminthiases, which are strongly dependent on environmental factors. Fascioliasis is a good example of an emerging/re-emerging parasitic disease in many countries as a consequence of many phenomena related to environmental changes as well as man-made modifications. The ability of F. hepatica to spread is related to its capacity to colonise and adapt to new hosts and environments, even at the extreme inhospitality of very high altitude. Moreover, the spread of F. hepatica from its original European range to other continents is related to the geographic expansion of its original European lymnaeid intermediate host species Galba truncatula, the American species Pseudosuccinea columella, and its adaptation to other lymnaeid species authochthonous in the newly colonised areas. Although fasciolopsiasis and gastrodiscoidiasis can be controlled along with other food-borne parasitoses, fasciolopsiasis still remains a public health problem in many endemic areas despite sustained WHO control programmes. Fasciolopsiasis has become a re-emerging infection in recent years and gastrodiscoidiasis, initially supposed to be restricted to Asian countries, is now being reported in African countries.

Animals↗

Phenotypic analysis of adults and eggs of Fasciola hepatica by computer image analysis system.

Knowledge of the morphological phenotypes of the liver fluke Fasciola hepatica (Trematoda: Digenea) is analysed. The influence of parasite age on its dimensions, the adult fluke growth model, variation in a biometric variable versus time, and variation in a biometric variable versus another biometric variable (allometric model) are revised. The most useful allometric model appears to be (y2 m-y2)/y2=c [(y1 m-y1)/y1](b), where y1=body area or body length, y2=one of the measurements analysed, y1 m, y2 m=maximum values towards which y1 and y2, respectively, tend, and c, b=constants. A method based on material standardization, the measurement proposal and allometric analysis is detailed. A computer image analysis system (CIAS), which includes a colour video-camera connected to a stereomicroscope (for adult studies) and a microscope (for egg studies), facilitates the processing of digital imaging. Examples of its application for the analysis of the influence of different factors on the liver fluke phenotype are shown using material from the Northern Bolivian Altiplano, where human and domestic animal fascioliasis is caused by F. hepatica only. Comparisons between the development of livestock fluke populations from highlands and lowlands are discussed and the relationships between host species and liver fluke morphometric patterns is analysed.

Altitude↗

Theoretical efficiency of a televisiting service for home care support.

We have made a theoretical study of the potential for televisiting. All journeys made by the home care support team in an area of Madrid were reviewed to study the possibility of using televisiting. During the year 2000 the team provided an average of seven home visits a day. The home visits took 30 min on average, and the journey time was 30 min for urban areas and 45 min in the suburbs. We estimated that two of each day s visits could be carried out by telemedicine, with a mean duration of 15 min each. A model was used to calculate the resource demands and the potential cost-savings of televisiting compared with traditional home care. Using televisiting, 62% more suburban oncology patients could be managed and a cost reduction of euro;6 per visit could be achieved after 10 weeks.

Aged↗

User satisfaction with home telecare based on broadband communication.

Home telecare services based on broadband communication were established in five locations in Europe. Two different types of telecare unit were developed: one based on a PC or set-top box containing a videoconferencing codec and another on off-the-shelf videoconferencing units. The participants in the project were 13 medical staff, 135 patients and 88 people informally caring for the patients. Questionnaires were used to evaluate user satisfaction with eight telecare services. Almost all participants rated the usability of the system as good or excellent. A total of 105 telecare sessions were scored by the medical staff. Overall, the quality of audio and video communication was judged satisfactory. For the patients and carers, the perceived quality of communication was also satisfactory and did not vary significantly between sites. The medical staff were reasonably satisfied with how the service supported them in their work. Except for the item about being able to support patients in a critical situation, medical staff agreed that an improved quality of health services was offered through telecare. All participants agreed that personal information was treated confidentially and that there was little risk in using the telecare services. The medical staff trusted the assessments they could make remotely while using the telecare system. Although the findings cannot be generalized due to the small number of telecare sessions and the relatively short duration of the experiment, the results encourage further research.

Adolescent↗

Relationships between host species and morphometric patterns in Fasciola hepatica adults and eggs from the northern Bolivian Altiplano hyperendemic region.

The highest prevalences and intensities of human fasciolosis by Fasciola hepatica are found in the northern Bolivian Altiplano, where sheep and cattle are the main reservoir host species and pigs and donkeys the secondary ones. Morphometric comparisons of many linear measurements, areas and ratios of F. hepatica adults (from sheep, cattle and pigs) and eggs (from sheep, cattle, pigs and donkeys) in natural liver fluke populations of the Bolivian Altiplano, as well as of F. hepatica adults and eggs experimentally obtained in Wistar rats infected with Altiplanic sheep, cattle and pig isolates, were made using computer image analysis and an allometric model. Although morphometric values of adult flukes from natural populations of sheep, cattle, and pigs showed great overlap, there were clear differences in allometric growth. The allometries analyzed were: body area (BA) versus body length (BL), BA versus body width (BW), BA versus perimeter (Pe), BA versus distance between posterior end of body and ventral sucker (P-VS), BL versus BW, BL versus Pe, and BL versus P-VS. These allometries show a good fit in the seven pairs of variables in all the populations examined. Comparative statistical analysis of the allometries shows that fluke adult populations from sheep, cattle and pigs significantly differ in BL versus BW and BL versus P-VS functions. Statistical analysis of F. hepatica egg size shows characteristic morphometric traits in each definitive host species. In experimentally infected rats, fluke adult allometry and egg morphometry do not vary depending on the Altiplanic definitive host species isolate. Our study reveals that the definitive host species decisively influences the size of F. hepatica adults and eggs, and these influences do not persist in a rodent definitive host model.

Animals↗

Developmental differences in the uterus of Fasciola hepatica between livestock liver fluke populations from Bolivian highlands and European lowlands.

A morphometric study of the uterus area (UA) of Fasciola hepatica adults was carried out with the aid of a computer linked to a stereomicroscopic 3CCD colour video camera using image analysis software. The UA of adult liver flukes found in naturally infected sheep, cattle and pig from the endemic human fascioliasis zone of the northern Bolivian Altiplano highlands was compared with that of flukes found infecting sheep and cattle from Valencia, Spain and cattle from Corsica, France (collectively, European lowlands). Liver fluke UA was examined using an allometric model. A comparison of the allometry of the liver fluke UA in different host species from Bolivia revealed no significant differences. Similarly, no statistically significant differences were found between UA of Valencian and Corsican populations. However, the Bolivian sheep and cattle liver fluke populations proved to have a UA smaller than that of the European populations. These results indicate differences between the liver fluke population of highlands and lowlands, regarding UA. This paper discusses the possible relationship between the characteristic of having a reduced uterine development and the liver fluke adult stage adapting to host populations living at very high altitudes.

Altitude↗

Evaluation of nonglucose carbohydrates in parenteral nutrition for diabetic patients.

OBJECTIVE: There is little information on the advantages of nonglucose carbohydrates in total parenteral nutrition (TPN) for diabetic patients. The aim of this study is to evaluate glycemic control and insulin requirements in diabetic patients who received TPN with different sources of carbohydrates, and to determine whether insulin requirements are different when septic and non-septic diabetic patients are studied. MATERIALS AND METHODS: One-hundred and thirty-eight patients were randomly divided into two groups receiving either glucose (G), n=71, or glucose-fructose-xylitol 2:1:1 (GFX), n=67. There were no differences between the demographic or anthropometric characteristics of the groups, nor between the patients with diabetes mellitus type 1 and type 2, nor the initial TPN composition. Acceptable glycemic control was considered when glycemia reached <200 mg/dl. RESULTS: Glycemic control was attained in 79.7% of patients (74.6 vs 85.1%), in the same period of treatment. At the end of treatment, insulin requirements were not different (45+/-19 vs 45+/-26 UI/day) in both groups, while similar amounts of carbohydrates (191+/-36 vs 187+/-45 g/day) were infused. The ratio insulin/body weight and insulin/carbohydrates were equal in both groups. In the GFX group nonseptic and septic patients needed less and more insulin, respectively, than their counterparts in the G group. No major adverse events related to carbohydrate infusions were observed. CONCLUSIONS: Either G or GFX could be used in TPN for diabetic patients, providing glycemic control in most cases with similar insulin requirements. GFX mixtures were slightly more beneficial to attain glycemic control in nonseptic patients, but septic diabetic patients had higher insulin needs in this group.

Aged↗

Clinical features and long-term outcome of obesity-associated focal segmental glomerulosclerosis.

BACKGROUND: Several cases of obesity-associated focal segmental glomerulosclerosis (OB-FSG) have been reported but little is known about the clinico-pathological features of this entity and its long-term outcomes. METHODS: We studied 15 obese patients (BMI 35+/-5.2 kg/m(2)) with biopsy-proven FSG. They were compared with a control group of 15 non-obese patients with idiopathic FSG (I-FSG). RESULTS: Mean proteinuria at the time of renal biopsy was 3.1+/-2 g/24 h in OB-FSG; it reached the nephrotic range (> or =3.5 g/24 h) during follow-up in 12 patients (80%), but none of them had oedema, hypoproteinaemia, or hypoalbuminaemia. Proteinuria was more marked amongst I-FSG (6.5+/-4.2 g/24 h) and most of them developed oedema and biochemical nephrotic syndrome. Glomerulomegaly was observed in all renal biopsies from OB-FSG patients (mean glomerular diameter 256+/-24 microm in OB-FSG vs 199+/-26 microm in I-FSG, P<0.001). Twelve OB-FSG patients (80%) were treated with ACE inhibitors (ACEI) and proteinuria significantly decreased within the first 6 months of treatment but showed a later increase. None of the obese patients achieved a sustained weight loss. Seven (46%) patients with OB-FSG experienced a progressive renal insufficiency and five of them started intermittent dialysis. Kaplan-Meier estimated probabilities of renal survival after 5 and 10 years were 77 and 51%, respectively, in OB-FSG patients, and 52 and 30% in I-FSG (P<0.05). The risk of developing progressive renal failure among OB-FSG patients was statistically correlated with serum creatinine and creatinine clearance at presentation. CONCLUSIONS: OB-FSG indicates a poor prognosis with almost one-half of patients developing advanced renal failure. Knowledge of the clinico-pathological features of this entity (obesity, FSG lesions with glomerulomegaly, absence of nephrotic syndrome despite nephrotic-range proteinuria) should be helpful in establishing an accurate and early diagnosis.

Adult↗

Modelling home televisiting services using systems dynamic theory.

A quantitative model was developed to study the provision of a home televisiting service. Systems dynamic theory was used to describe the relationships between quality of care, accessibility and cost-effectiveness. Input information was gathered from the telemedicine literature, as well as from over 75 sessions of a televisiting service provided by the Severo Ochoa Hospital to 18 housebound patients from three different medical specialties. The model allowed the Severo Ochoa Hospital to estimate the equipment needed to support increased medical contacts for intensive cardiac and other patients.

Adult↗

[Efficacy of quinagolide in the treatment of a patient with hypophyseal resistance to thyroid hormones].

The pituitary resistance to thyroid hormones (PRTH) is not very frequent and well-known entity, their treatment it continues being topic of controversy. In this work we have evaluated the quinagolida effectiveness in the treatment of it unites patient with (PRTH). The relationship among thyroid stimulating hormone (TSH) and free triiodothyronine (FT3) it was used as marker of the thyroid resistance and of the response to the treatment. The concentrations of TSH and FT3 were normalized after adding quinagolida to methimazole. These results suggest that the quinagolida could be an useful drug in the treatment of this pathology, next to the classic treatments.

Adult↗

Impact of a broadband interactive televisit/teleconsultation service for residential and working environments.

The availability of health care attention at the point of need is one of the key benefits of telemedicine. Home environment and working place are the two scenarios selected in this article to evaluate the impact of a televisit and teleconsultation service. 31 users from four different medical and patient groups participated in this study supported by European Commission ATTRACT project. The experiences, carried out in Madrid and Valencia Spanish sites, benefited from interactive broadband access networks to provide cost-effective telecare services. Key areas analyzed encompass systems usability, clinical outcomes, patients quality of care and infoethic issues. Services advantages were verified and compared both from patients and medical staff points of view. Main benefits pointed out refer to displacement reduction, better communication doctor/patient, provision of comfort or friendliness, more precise therapy follow-up and increases in patients sense of well being.

Attitude of Health Personnel↗

[Home parenteral nutrition. A six-year combined program (adult and pediatric patients)].

BACKGROUND: To describe the outcomes of an adult-pediatric home parenteral nutrition (HPN) program. PATIENTS AND METHODS: Retrospective protocol between 1993 and 1999. RESULTS: Sixteen adults (average 45.7 years) and eight children (3.1 years) were included in the program. Mean length of parenteral nutrition was 507 (SD: 624) and 155 (SD: 129) days respectively. Total follow-up time was 8,119 days for adults and 1,242 for children. Cancer was the main diagnosis in adults and intractable diarrhea in children. Central venous catheter related infections were the most usual complication (0.63 and 1.2 episodes/patient/year). There were no deceases due to the HPN in the period of study. CONCLUSIONS: HPN is an effective and safe technique, although prevalence and incidence in Spain are low.

Adult↗

Fasciola hepatica: lithogenic capacity in experimentally infested rats and chemical determination of the main stone components.

A study was done of the possible association between the development of common bile-duct stones and the presence of worms in rats experimentally infected with Fasciola hepatica. A total of 157 rats were individually infected with 20 metacercariae, and another 40 animals served as controls. The rats were dissected at 100, 200, 300, and 400 days postinfection (p.i.). A significant association was observed between the observation of stones and the presence of F. hepatica adults. The global frequency of bile-duct lithiasis in the parasitized rats was 22%, with a significantly lower incidence being observed in the younger group (100 days p.i.). Different analytical techniques were used to determine the main stone components. Energy-dispersive X-ray microanalysis showed calcium to be the main component in all cases (82-94%). Scanning electron microscopy, nuclear magnetic resonance ([1H]- and [13C]-NMR), and mass spectrometry revealed the predominance of palmitic (C-16) and stearic (C-18) acid.

Animals↗