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Biomedical subjects

M Marín

Publications and source records attributed to M Marín.

At least 19 recordsLinked to original sources
PubMed2006

[Intimal sarcoma of the pulmonary artery: a rare cause of pulmonary hypertension].

Intimal sarcoma of the pulmonary artery is a rare tumor that is usually diagnosed during surgery or autopsy. Such tumors are characterized by local growth, with only slight ability to metastasize. Diagnosis is difficult and often delayed owing to the nonspecific nature of the symptoms. Since intimal sarcoma of the pulmonary artery is so rare and insidious it is often confused with pulmonary thromboembolism and is therefore treated inappropriately with prolonged anticoagulation or thrombolysis. With a mean survival of 12 months from the onset of symptoms, the prognosis is poor. We present the case of a woman who was preoperatively diagnosed with intimal sarcoma of the pulmonary artery and who underwent surgical resection with no apparent recurrence at long term follow-up. A review of the literature is also included.

Female↗
PubMed2006

Analysis of the Trypanosoma cruzi cyclophilin gene family and identification of Cyclosporin A binding proteins.

The Trypanosoma cruzi cyclophilin gene family comprises 15 paralogues whose nominal masses vary from 19 to 110 kDa, namely TcCyP19, TcCyP20, TcCyP21, TcCyP22, TcCyP24, TcCyP25, TcCyP26, TcCyP28, TcCyP29, TcCyP30, TcCyP34, TcCyP35, TcCyP40, TcCyP42 and TcCyP110. Under the conditions used, only some of the T. cruzi cyclophilin paralogue products could be isolated by affinity chromatography. The 15 paralogues were aligned with 495 cyclophilins from diverse organisms. Analyses of clusters formed by the T. cruzi cyclophilins with others encoded in various genomes revealed that 8 of them (TcCyP19, TcCyP21, TcCyP22, TcCyP24, TcCyP35, TcCyP40, TcCyP42 and TcCyP110) have orthologues in many different genomes whereas the other 7 display less-defined patterns of their sequence attributes and their classification to a specific group of cyclophilin's orthologues remains uncertain. Seven epimastigote cDNA clones encoding cyclophilin isoforms were further studied. These genes were found dispersed throughout the genome of the parasite. Amastigote and trypomastigote mRNAs encoding these 7 genes were also detected. We isolated 4 cyclosporin A-binding proteins in T. cruzi epimastigote extracts, which were identified by mass spectrometry as TcCyP19, TcCyP22, TcCyP28 and TcCyP40. Cyclosporin A-binding to these cyclophilins might be of importance to the mechanism of action of Cyclosporin A and its non-immunosuppressive analogues, whose trypanocidal effects were previously reported, and therefore, of potential interest in the chemotherapy of Chagas' disease.

Amino Acid Sequence↗
PubMed2005

An improved protocol for pulsed-field gel electrophoresis typing of Clostridium difficile.

Pulsed-field gel electrophoresis (PFGE) is the 'gold standard' technique for bacterial typing and has proved to be discriminatory and reproducible for typing Clostridium difficile. Nevertheless, a high proportion of strains are non-typable by this technique due to the degradation of the DNA during the process. The introduction of several modifications in the PFGE standard procedure increased typability from 40% (90 isolates) to 100% (220 isolates) while maintaining the high degree of discrimination and reproducibility of the technique.

Bacterial Typing Techniques↗
PubMed2005

Toxigenic status of Clostridium difficile in a large Spanish teaching hospital.

The aim of this study was to evaluate the toxigenic status of circulating strains of Clostridium difficile in a large teaching hospital. Overall 220 isolates were studied of which 199 (90.5 %) produced both large clostridial toxins detected by conventional methods. Ten more strains (4.5 %) had toxin A and B genes detectable by PCR. Eleven (5.0 %) variant strains (A- B+) were detected among the isolates studied and 10 strains (4.5 %) had the binary toxin genes (cdtA and cdtB).

Bacterial Proteins↗
PubMed2005

In vitro activity of ramoplanin against Clostridium difficile, including strains with reduced susceptibility to vancomycin or with resistance to metronidazole.

We evaluated the in vitro activity of ramoplanin, an antimicrobial compound that inhibits cell wall synthesis by acting at the level of lipid intermediate formation, against Clostridium difficile. We included strains with reduced susceptibilities to vancomycin (vancomycin-intermediate [Van(i)] strains) or with resistance to metronidazole (Mtz(r)), in order to assess the potential utility of ramoplanin for the treatment of C. difficile-associated diarrhea. We tested the activity of ramoplanin against a total of 105 nonduplicate clinical isolates of toxigenic C. difficile, including 8 Van(i) isolates and 6 Mtz(r) isolates, obtained from our laboratory. Ramoplanin was active against all strains tested at concentrations ranging from 0.03 to 0.5 microg/ml (MICs at which 50 and 90% of isolates were inhibited, 0.25 microg/ml; geometric mean MIC, 0.22 microg/ml). All isolates, independently of their levels of susceptibility to vancomycin or metronidazole, were considered susceptible to ramoplanin (MICs, < or =0.5 microg/ml).

Clostridioides difficile↗
PubMed2005

Serotoninergic system blockage in the prepubertal rat inhibits spermatogenesis development.

The stimulatory and inhibitory role of serotonin in gonadotropin secretion and in the onset of puberty in the male rat has been previously described, but its role in the establishment of spermatogenesis is not known. The aim of this study was to investigate the effects of serotoninergic inhibition by p-chloroamphetamine (pCA) on the prepubertal-to-adult stage of the rat reproductive system. Hypothalamic serotonin, gonadotropins and sex steroid hormone concentrations were measured, and a histopathological analysis of seminiferous epithelium was carried out on animals treated with pCA from day 30 and killed at 45 or 65 days of age. The pCA treatment significantly reduced the hypothalamic levels of serotonin and its metabolite (5-hydroxyindole-3-acetic acid). This inhibition did not affect the sex steroid hormone or LH concentrations, but rather it induced an increase in FSH concentration in animals of both ages. Spermatogenesis was impaired by pCA treatment. Disruption of seminiferous epithelium and the death of numerous germ cells were observed. Sperm produced by pCA-treated animals was of poor quality and appeared in small quantities. Apparently, serotonin depletion did not affect communication between the hypothalamus and the pituitary, but the FSH increase could have been related to alterations in the seminiferous epithelium effects. The seminiferous epithelium cycle was altered in rats killed at both 45 and 65 days of age, because at each age of killing the distribution of spermatogenesis stages was different. Germ cell apoptosis did not appear to be related to changes in the FSH concentrations, but other factors produced during spermatogenesis could have been involved in this induction. This study showed that serotonin was necessary for the development of normal spermatogenesis in prepubertal rats.

Animals↗
PubMed2005

[Immunomodulatory treatment with beta-interferon in patients with cervical intraepithelial neoplasia and human papillomavirus infection: long-term follow-up].

The aim of this study was to evaluate the long-term efficacy of beta-interferon treatment in the management of cervical intraepithelial neoplasia associated with human papillomavirus (HPV) infection in a selected group of patients. Thirty-nine patients who had histologically proven cervical intraepithelial neoplasia I or II with concurrent HPV infection were administered 27,000,000 IU of intramuscular beta-interferon. Periodical controls were carried out based on Papanicolaou smears and/or colposcopic examination and DNA HPV determination was performed by hybridation test, for a maximum of 8 years' follow-up. An initial complete response rate of 75% was obtained, with a recurrence rate of 25%, cervical intraepithelial neoplasia with late manifestation was of higher grade. Treatment interruption due to side-effects was not necessary. Associated viral infections appeared to be a recurrence risk factor, but not smoking or parity. While immunomodulatory treatment with beta-interferon has good long-term results in cervical intraepithelial neoplasia I/II treatment, wider randomized studies are required to obtain conclusive results.

Adjuvants, Immunologic↗
PubMed2004

[Intramuscular juvenile xantogranuloma].

Deep or intramuscular juvenile xanthogranuloma (JXG) is very rare. There are, however, some clinical and histological similarities between the case we present and the few cases that have been published in the literature. Although most of them will need histologic confirmation to establish the final diagnosis, surgeons who are operating tumors of infancy should consider it in the differential diagnosis of well circumscribed, rapidly growing dorsal masses in children under 3 years of age. Macroscopic appearance upon excision can help to support the diagnosis. Knowledge of this variant of JXG may avoid aggressive diagnostic or therapeutic procedures.

Female↗
PubMed2003

[Pseudomonas aeruginosa: a multicenter study in 136 hospitals in Spain].

A cooperative group of 136 Spanish hospitals identified 1014 isolates of P. aeruginosa in one week. It was estimated that Spanish microbiology laboratories identified 168 P. aeruginosa isolates per 100,000 inhabitants population and year (25 isolates for every 1,000 hospital admissions/year). P. aeruginosa was recovered in 5.3% of all the samples with bacterial isolates. Seventy-five percent of samples containing P. aeruginosa came from the lower respiratory tract, wound exudates, abscesses and urine. The three most common serotypes present in Spain were found to be 0:1, 0:4 and 0:11 and constituted more than 50% of all isolates. The antimicrobials active against more than 85% of all the isolates included: ceftazidime (85.2%), piperacillin-tazobactam (92.8%), imipenem (86.2%), meropenem (92.2%) amikacin (91.4%) and tobramycin (91.2%). The study showed a high rate of resistance to ciprofloxacin (22.7%) and gentamicin (31.1%). Of the 529 patients who underwent clinical follow-up, 25.5% showed P. aeruginosa colonization and the remaining 74.5% had clinical infections. We estimated an incidence rate of 88.4 patients infected with P. aeruginosa per 100,000 inhabitants and year (13.8 cases per 1000 hospital admissions and year). Overall, 42% were community acquired. The overall mortality in this study was 15%, and mortality attributable to P. aeruginosa infections was 5%. After logistical regression analysis, the two independent predictors of mortality were the presence of a rapidly fatal underlying condition and the presence of bacteremia. In Spain, P. aeruginosa is much more than a cause of severe nosocomial infections in immunocompromised patients.

Anti-Bacterial Agents↗
PubMed2002

Demolition of a hospital building by controlled explosion: the impact on filamentous fungal load in internal and external air.

The demolition of a maternity building at our institution provided us with the opportunity to study the load of filamentous fungi in the air. External (nearby streets) and internal (within the hospital buildings) air was sampled with an automatic volumetric machine (MAS-100 Air Samplair) at least daily during the week before the demolition, at 10, 30, 60, 90,120, 180, 240, 420, 540 and 660 min post-demolition, daily during the week after the demolition and weekly during weeks 2, 3 and 4 after demolition. Samples were duplicated to analyse reproducibility. Three hundred and forty samples were obtained: 115 external air, 69 'non-protected' internal air and 156 protected internal air [high efficiency particulate air (HEPA) filtered air under positive pressure]. A significant increase in the colony count of filamentous fungi occurred after the demolition. Median colony counts of external air on demolition day were significantly higher than from internal air (70.2 cfu/m(3) vs 35.8 cfu/m(3)) (P < 0.001). Mechanical demolition on day +4 also produced a significant difference between external and internal air (74.5 cfu/m(3) vs 41.7 cfu/m(3)). The counts returned to baseline levels on day +11. Most areas with a protected air supply yielded no colonies before demolition day and remained negative on demolition day. The reproducibility of the count method was good (intra-assay variance: 2.4 cfu/m(3)). No episodes of invasive filamentous mycosis were detected during the three months following the demolition. Demolition work was associated with a significant increase in the fungal colony counts of hospital external and non-protected internal air. Effective protective measures may be taken to avoid the emergence of clinical infections.

Air Conditioning↗
PubMed2002

Studies on the photostability and phototoxicity of aloe-emodin, emodin and rhein.

Aloe-emodin (1), emodin (2) and rhein (3) were found to be photolabile by visible (390-500 nm) light under aerobic conditions. The drugs 1, 2 and 3 were phototoxic in vitro when examined by the photohemolysis test under both oxygen and argon atmospheres, although the photohemolysis rate was markedly lower under anaerobic conditions. The experiments were also carried out in the presence of butylated hydroxyanisole (BHA), reduced glutathione (GSH), sodium azide (NaN3) and superoxide dismutase (SOD). Based on the inhibition of this process on addition of BHA, GSH, SOD and NaN3, there would seem to be involvement of free radicals (type I mechanism) and singlet oxygen in the process (type II mechanism). The in vitro phototoxicity of this anthraquinone series was also verified in a lipid-photoperoxidation test with linoleic acid. In summary, this anthraquinone series is phototoxic in vitro. This behavior can be explained through the involvement of singlet oxygen and stable photoproducts.

Acetylcholinesterase↗
PubMed2001

In vitro taurocholate-induced segmentation and clustering of Mesocestoides vogae (syn. corti) tetrathyridia (Cestoda)--inhibition byh cestocidal drugs.

Mesocestoides vogae (syn. M. corti) tetrathyridia were cultured in the presence of sodium taurocholate, for the purpose of exploring the suitability of this organism for the in vitro assay of cestocidal drugs. Parasite clustering and segmentation were observed as taurocholate-dependent effects in biphasic and monophasic media, respectively. Interestingly, representative members of two major classes of known cestocidal agents (namely, albendazole and praziquantel) blocked these effects. Furthermore, it was possible to determine a specific concentration of the drugs that inhibited clustering and segmentation (minimum inhibitory concentration). In contrast, no inhibition was obtained in the presence of anthelmintics without cestocidal activity. These observations open the way for further studies focused at understanding how the activity of the drugs is involved in the suppression of the taurocholate-induced effects.

Animals↗
PubMed2001

Agronomic use of biotechnologically processed grape wastes.

Grape waste was composted by biodegradation and subsequently used as an organic fertilizer for 20 day-corn. Combinations of recently compressed grape waste and hen droppings (10% w/w) were prepared to study the activating effect of hen droppings and the effect of aeration on the composting process. The final hydrogen potential (pH), %C, %N and C/N ratio, indicated an adequate development of the bioprocess. Satisfactory results were observed when the products were applied at several doses (1,000-4,000 kg/ ha) as a soil conditioner for corn seed germination in greenhouses. Only the addition of hen droppings had a significant effect (P < 0.05) on corn dry matter (14% increase). A dose of 3000 kg/ha was considered as optimal and was used supplemented with triple superphosphate (TSP) in agronomic trials. All the treatments produced greater corn dry matter (P < 0.05) than the chemical industrial fertilizer used as a control (0.52-0.71 g/pot for the organic fertilizers vs 0.45 g/pot for the control). Anaerobic conditions and hen droppings addition significantly produced (P < 0.05) higher corn dry matter.

Biodegradation, Environmental↗
PubMed2000

The gene encoding the metacyclogenesis-associated transcript Mat-1 is conserved in the genus Leishmania and shows a tendency to form dimers upon protein expression.

The Leishmania infantum Mat-1 gene--recently described in L. major as a highly stage-specific, metacyclogenesis-associated transcript--has been cloned. The 420-bp Mat-1 coding region is conserved with respect to the L. major gene (82% sequence homology). Analysis of the predicted amino-acid sequence reveals structural motifs showing homology with the class of leucine-zipper transcription factors. Southern-blot hybridization analysis suggests that Mat-1 is a low-copy-number gene, probably consisting of two gene copies. The recombinant Mat-1 protein expressed in fusion with the Escherichia coli maltose-binding protein shows a tendency to form dimers in the presence of the leucine-rich C-terminal domain. Bacteria expressing the Mat-1 open reading frame are highly growth-attenuated and tend to delete or modify the insert, which suggests that expression of Mat-1 is toxic for the bacteria.

Amino Acid Sequence↗
PubMed2000

[Midterm results of coronary bypass surgery exclusively with arterial revascularization].

INTRODUCTION AND OBJECTIVES: In recent years, the exclusive use of arterial grafts in coronary surgery has been the surgical option to achieve maximum survival and minimum recurrence of coronary events. The aim of this study was to analyze the surgical results and follow up of this approach. PATIENTS AND METHODS: Over a period of six and a half years, 87 patients underwent coronary surgery using arterial grafts alone for revascularization. The mean age of the patients was 62 +/- 1 years with 78 men and 9 women; 22 patients (25%) were clinically unstable. The number of vessels affected per patient was 1.83 +/- 0.1, and the number of patients with one, two and three affected vessels, were 38 (44%), 26 (30%) and 23 (26%), respectively. The mean ejection fraction was 63 +/- 1.6. Emergency surgery was carried out in 13 cases (16%). RESULTS: A total of 1.9 +/- 0.1 grafts were implanted per patient and complete revascularization was achieved in 65 cases (75%). The left mammary artery was used in 87 cases (100%), the right mammary artery in 31 (35.6%) and the radial artery in 20 cases (23%). Hospital mortality was 1.1% (one case). During the postoperative period, 3 patients (3.4%) presented myocardial infarction, 12 (13.8%) atrial fibrillation and there were 3 cases of sternal dehiscence.A total of 86 patients (98.9%) were followed over a mean period of 24.5 +/- 0.5 months. Survival, angina-free period and period free of any coronary event at 5 years were 97 +/- 0.05%, 89 +/- 0.1% and 87 +/- 0.1% respectively (mean +/- standard error, CI 95%). On multivariate analysis, the presence of peripheral vascular disease (p < 0.015) and the development of low cardiac output (p < 0.04) or atrial fibrillation (p < 0.04) during the postoperative period were predictive factors for the appearance of coronary events during follow-up. CONCLUSIONS: Surgery exclusively with arterial grafts achieves good medium term results in relation to survival and time free of coronary events.

Arteries↗
PubMed2000

Phrenic nerve conduction study in demyelinating neuropathies and open-heart surgery.

OBJECTIVES: The aim of this study was to determine normal values of phrenic nerve conduction (PNC) in healthy individuals; to evaluate the subclinical extent of phrenic nerve involvement in Guillain-Barré syndrome (G-B) and hereditary motor and sensory neuropathy-I (HMSN-I), and to evaluate phrenic nerve damage after cardiac surgery. MATERIALS AND METHODS: PNC was performed by transcutaneous stimulation in the neck and recording the diaphragmatic potential from surface electrodes placed at the seventh and eight intercostal spaces. PNC was performed bilaterally in 25 healthy volunteers and 25 patients before and after open-heart surgery. Right PNC was also performed in 5 cases with G-B and 5 patients with HMNS-I. RESULTS: Latency and amplitude of the diaphragmatic potential were the same in controls and in patients with cardiac disease before surgery. After surgery, 28% of patients had left phrenic nerve inexcitability, and 8% had reduced amplitude of the response. These 9 patients demonstrated elevation of the left hemidiaphragm on chest radiography. Left PNC performed 1 year after the operation showed improvement in latency and amplitude of the responses in all except one patient. PNC was prolonged in 4 out of 5 cases with G-B and in all patients with HMNS-I. CONCLUSIONS: PNC is an easy and reliable method in evaluating phrenic nerve damage due to hypothermia or primary stretch injury in patients after cardiac surgery. PNC may be helpful in detecting diaphragmatic involvement before clinical ventilatory insufficiency in demyelinating neuropathies such as G-B and HMNS-I.

Adult↗
PubMed2000

Effect of praziquantel on the strobilar development of Mesocestoides corti in vitro.

The effect of praziquantel (PZQ) on the strobilar development of the cyclophyllidean cestode Mesocestoides corti was explored. Mesocestoides corti larvae were cultivated under conditions reported to favour their differentiation to the adult stage. Parasites were exposed to 0.1 microg ml(-1) PZQ for 16 h and subsequently transferred to drug-free medium. The ocurrence of segmentation--an early event of the larval somatic differentiation to the adult worm-- was considered as quantitative data. This phenomenon was evidenced earlier in worms transiently exposed to PZQ with respect to control cultures. Moreover, the rate of segmentation of drug-treated worms at the end of the experiment almost doubled that of control worms. To date, no similar effect on any cestode developmental process has been reported for an anthelmintic drug. In the light of the existing knowledge and understanding of PZQ mechanisms of action, the proposed experimental approach could contribute to the elucidation of pathways and mechanisms involved in cestode strobilar development.

Animals↗