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Biomedical subjects

F Martinez

Publications and source records attributed to F Martinez.

At least 19 recordsLinked to original sources

Development of a citrus genome-wide EST collection and cDNA microarray as resources for genomic studies.

A functional genomics project has been initiated to approach the molecular characterization of the main biological and agronomical traits of citrus. As a key part of this project, a citrus EST collection has been generated from 25 cDNA libraries covering different tissues, developmental stages and stress conditions. The collection includes a total of 22,635 high-quality ESTs, grouped in 11,836 putative unigenes, which represent at least one third of the estimated number of genes in the citrus genome. Functional annotation of unigenes which have Arabidopsis orthologues (68% of all unigenes) revealed gene representation in every major functional category, suggesting that a genome-wide EST collection was obtained. A Citrus clementina Hort. ex Tan. cv. Clemenules genomic library, that will contribute to further characterization of relevant genes, has also been constructed. To initiate the analysis of citrus transcriptome, we have developed a cDNA microarray containing 12,672 probes corresponding to 6875 putative unigenes of the collection. Technical characterization of the microarray showed high intra- and inter-array reproducibility, as well as a good range of sensitivity. We have also validated gene expression data achieved with this microarray through an independent technique such as RNA gel blot analysis.

Citrus↗

Prophylaxis of early bacterial infections after autologous peripheral blood stem cell transplantation (PBSCT): a matched-pair study comparing oral fluoroquinolones and intravenous piperacillin-tazobactam.

The safety and efficacy of early bacterial prophylaxis with piperacillin-tazobactam were prospectively evaluated in 51 autologous peripheral blood stem cell transplantation (PBSCT) recipients. The results were compared with those obtained in 51 control patients receiving oral fluoroquinolones in a retrospective matched-pair control study. Overall, 76% of the study group and 98% of the control group developed at least one febrile episode during neutropenia (P=0.002). Time from neutropenia to the first febrile episode (FFE) was significantly longer in the study group than in the control group (P=0.04). Once a febrile episode appeared, the duration of fever was significantly longer in cases than in controls (median of 5 and 2 days respectively, P<0.001), and led to a more frequent use of empirical amphotericin B (AmB), not statistically significant (P=0.13). However, the total time of antibiotic administration was significantly greater in the control than in the study group (P=0.05). The duration of AmB treatment shows a trend toward a longer duration in the control than in study group (P=0.2). Overall, 86% of the Gram-positive bacteremia and 85% of the Gram-negative bacteria were susceptible to the tested antibiotics. Our study suggests that a subgroup of patients could benefit from prophylaxis with piperacillin-tazobactam without increasing toxicity or bacterial resistance.

Adolescent↗

Effect of the interval between estrus onset and artificial insemination on sex ratio and fertility in cattle: a field study.

We have carried out a field trial in cattle to study the effect of the interval between the onset of estrus and AI on sex ratio and fertility. Data were obtained from 716 cows that had been inseminated at different times between 8 and 44 h from the visual detection of estrus. Before analyzing the data, it was grouped in three intervals considering the time between estrus onset and AI (8-18, 18-30, and > or = 30 h). Our results show that the percentage of calved females (73.05%) is significantly superior for early inseminations (8-18 h), and it decreases 1.85% per hour from the onset of estrus. Delayed AIs (> or = 30 h) produce a significant deviation of the sex ratio towards the males (72.06%); nevertheless, fertility (percentage of successful pregnancies) diminishes significantly, from 66.19% (8-18 h) to 45.35% (> or = 30 h). In conclusion, variations in the interval between the onset of estrus and AI modify sex ratio. However, we must consider its effect on fertility.

Animals↗

Clinical application of laser-assisted ICSI: a pilot study.

Human oocyte survival after intracytoplasmic sperm injection (ICSI) can be compromised by abnormal oolemma breakage patterns during the penetration of the microinjection needle. We previously reported a case of repeated ICSI failures associated with abnormal oolemma breakage in which a substantial improvement and successful pregnancy were achieved by performing ICSI through a laser-drilled hole in the zona pellucida (laser-assisted ICSI). This study was undertaken to compare the efficacy of laser-assisted ICSI with that of conventional ICSI in patients whose oocytes present this particular feature. Oocytes treated by laser-assisted ICSI (n=140) survived better (97.9% versus 85.7%; P<0.05) and tended to form more two-pronucleated zygotes (78.6% versus 69.2%; P=0.07) and less zygotes with three or more pronuclei (2.8% versus 7.8%; P=0.06) as compared with sibling oocytes treated by conventional ICSI (n=140). These data show that laser-assisted ICSI is suitable for oocytes with propensity for sudden oolemma breakage during conventional ICSI. The reduction of oocyte damage with laser-assisted ICSI as compared to conventional ICSI may be useful in other clinical indications where only few oocytes are available or when the oocyte survival after ICSI can be supposed to be compromised.

Female↗

Cumulative pregnancy rates after transfer of fresh and thawed embryos.

Frozen-thawed embryo transfer is an effective procedure that allows further possibilities of pregnancy in addition to those obtained after the fresh in vitro fertilization (IVF). In our follow-up study we analysed all fresh embryo transfer procedures and every frozen-thawed embryo transfer performed from January 2000 to December 2001 evaluating the cumulative pregnancy rates. The study population was divided into two groups according to the female age: <38 years (group I) and >38 years (group II). All the best embryos were chosen for transfer and all the supernumerary good quality embryos were cryopreserved on the day of transfer. The embryos were then thawed and manipulated using a new technique. In group I, 527 patients (619 cycles) underwent fresh embryo transfer and in 232 of them (238 cycles) the embryos were frozen (44% per patients and 38.4% per cycle). In group II, 156 patients (193 cycles) underwent fresh embryo transfer and in 14 of them (15 cycles) the embryos were frozen (9% per patient and 7.8% per cycle). The pregnancy rate of group I patients that had their supernumerary embryos frozen (232 patients and 238 cycles) was 47.4% per cycle and 48.7% per patient whereas in the same population of group II patients (14 patients and 15 cycles) the clinical pregnancy rate was 35.7% per cycle and 38.5% per patients. The cumulative clinical pregnancy rate after transfer of fresh and thawed embryos was: group I, 74% per cycle and 76% per patients; group II, 42.8% per cycle and 46.1% per patient. Frozen-thawed embryo transfer is a cost-effective practice.

Adult↗

Polscope analysis of meiotic spindle changes in living metaphase II human oocytes during the freezing and thawing procedures.

BACKGROUND: The clinical efficacy of the current methods used for cryopreservation of metaphase II human oocytes is low. Meiotic spindle disorders are thought to be largely responsible for this situation. METHODS: Supernumerary fresh metaphase II human oocytes were cryopreserved in 1,2-propanediol with 0.1 M sucrose using a slow freezing/rapid thawing programme. Meiotic spindles were analysed in these living metaphase II oocytes at sequential steps of the freezing and thawing procedures with the use of a computer-assisted polarization microscopy system (Polscope). RESULTS: The meiotic spindle was detected in all 56 oocytes (from 16 patients) before freezing and remained visible in all these oocytes throughout the preparation for freezing up to the time that they were loaded into cryopreservation straws. Immediately after thawing, the spindle was visible in 35.7% of oocytes, but it disappeared in all of the thawed oocytes during the subsequent washing steps. However, the spindle reappeared in all surviving thawed oocytes after washing (57.4%), by 3 h of incubation at 37 degrees C in culture medium. CONCLUSIONS: The current techniques of oocyte freezing and thawing inevitably cause meiotic spindle destruction. All spindles observed in thawed oocytes result from post-thaw reconstruction.

Cell Survival↗

[Recessive dystrophic epidermolysis bullosa (Hallopeau-Siemens) with IgA nephropathy: 4 cases].

BACKGROUND: The Hallopeau-Siemens type of recessive dystrophic epidermolysis bullosa (HS-RDEB) is a severe hereditary dermatosis, associated with a collagen VII deficiency. A chronic inflammatory syndrome, secondary to recurrent cutaneous infections, may be the cause of AA amyloidosis, with chronic renal failure, involving life prognosis. Less frequently, an IgA glomerulonephritis may occur and induce renal failure. Only two cases have been previously described. We report herein four new cases. CASE REPORT: We report four cases of HS-RDEB associated with IgA glomerulonephritis. A renal biopsy confirmed the diagnosis in all four cases. Later on, two patients had a second renal biopsy, indicated for deterioration of renal function. One of these patients showed AA type renal amyloidosis on the second biopsy. None of these six biopsies, conducted in our four patients led to local cutaneous complications. Subsequently three patients presented with terminal renal failure. Hemodialysis was set up, with good tolerance and improvement in quality of life. DISCUSSION: IgA glomerulonephritis should be suspected if a patient with HS-RDEB presents with hematuria. Renal biopsy is not contraindicated, confirms the diagnosis and helps to specify the prognosis. Hemodialysis is possible and well tolerated in the terminal stage of renal failure. There is not enough evidence for a genetic link between HS-RDEB and IgA glomerulonephritis, but repeated skin infections may be involved in the pathophysiology of the renal disease.

Adult↗

[A rare cause of pulmonary-renal syndrome with autoantibodies: primary antiphospholipid syndrome].

We present a case of primary antiphospholipid syndrome with acute renal failure and alveolar haemorrhage. He was successfully treated with cyclophosphamide, corticosteroids and plasma exchange. Patients with antiphospholipid syndrome may develop a broad spectrum of pulmonary disease. Pulmonary thromboembolism and pulmonary hypertension are the most common complications, but alveolar haemorrhage have also been reported. Other causes need to be excluded. Despite favourable outcome of many patients with association of plasma exchange, immunosuppressive drugs and anticoagulant therapy, definite conclusions about the best therapeutic regimen could not be draw.

Acute Kidney Injury↗

Eye feature extraction for diagnosing the facial phenotype associated with fetal alcohol syndrome.

Victims of fetal alcohol syndrome (FAS) exhibit a unique facial phenotype that is emphasised in diagnosis. Among the characteristic facial features, several occurring in the region of the orbits can be evaluated quantitatively using distance measurements. An algorithm is described for automatic extraction and measurement of eye features from stereo photographs. The algorithm was applied to photographs of 46 six-seven-year-old children. The approach relies on peak and valley maps and integral projection functions, to locate the eyes and extract the iris, and genetic algorithms to fit cubic splines to the upper and lower eyelids. Measurements obtained automatically using this algorithm were compared with measurements obtained manually from the photographs. Mean absolute differences between automatic and manual measurements were less than 1 mm for palpebral fissure length (PFL) and interpupillary distance (IPD). Absolute differences were less than 1 mm for 80.4% of PFLs and 100% of IPDs. Inner canthal distance and outer canthal distance did not compare favourably with manual measurements.

Algorithms↗

Implantation in patients over 40 and raising FSH levels--a review.

There is an evident decline of female fertility with age. This decline is mainly due to increased risk of pregnancy termination either after conception or after embryo implantation. Very likely the major cause of this embryo and pregnancy loss is chromosomal aneuploidies caused mostly by increasing rates of 'poor quality' oocytes. This phenomenon can be explained either by an age dependent accumulation of damage and/or by the hypothesis that the defective oocytes are there in the ovaries from the fetal life. 'Good quality' oocytes are ovulated first, leaving 'poor quality' oocytes to be ovulated later in life. Besides the quality of the oocytes which is mainly responsible of the embryo quality (we have not to forget a paternal effect) the process of implantation is dependent upon two variables: the probability of a viable embryo and that of a receptive uterine environment. From the oocyte donation model it seems that the endometrium also plays a minor role in human reproductive ageing as it does in some laboratory animals. However, besides some macroscopic possible causes which may play a role in the reduction of the age-related endometrial receptivity, there are so many endometrial factors possibly related to its receptivity which need to be further studied especially in older women.

Adult↗

Evaluation of the CD14 C-159 T polymorphism in the German Multicenter Allergy Study cohort.

BACKGROUND: Multiple genetic studies have shown linkage of atopy-related phenotypes to chromosome 5q31. In this region several candidate genes for atopy are localized such as the Th2 cytokines IL-4, IL-5 and IL-13, but also CD14, a receptor for LPS. Recently, a functional CD14 promoter polymorphism was related to total and specific IgE responsiveness. OBJECTIVE: The aim of our study was to evaluate the role of this single nucleotide polymorphism (SNP) in a large German birth cohort. METHODS: Atopy-related phenotypes were longitudinally carefully evaluated in over 800 children from birth to the age of 10 years. Yearly visits included standardized interviews, physical examinations and determination of total and specific IgE antibodies. Pulmonary function tests and histamine provocations were performed at the age of seven. Eight-hundred and seventy-two children of the Multicenter Allergy Study (MAS) cohort were genotyped using melting curve and restriction digest analyses. RESULTS: CD14-159 allele frequencies were consistent with previous reports, however, no association of the SNP with asthma, atopic dermatitis, allergic rhinitis, total or specific IgE levels could be observed. CONCLUSION: The CD14-159 SNP might not play a major role in the development of atopy in German children.

Follow-Up Studies↗

Iatrogenic Creutzfeldt-Jakob disease subsequent to dural graft: persisting risk after 1987.

The first case of Creutzfeldt-Jakob disease (CJD) related to the use of a dura mater graft of cadaveric origin was identified in 1987 and this procedure is now considered as one of the main causes of iatrogenic CJD. Although the decontamination procedure for the preparation of graft material was modified, the product was withdrawn from the market in many countries a few years later and replaced by synthetic material. In this context, two patients treated in our institution developed CJD following a cadaveric dural graft performed after cerebral and lumbar trauma. Their clinical presentation, showing predominant cerebellar symptoms, late deterioration and myoclonic jerks, and a rapid disease course until death, was similar to that of previously reported cases involving the iatrogenic form. As the graft for one of the patients was performed in 1991 (several years after modification of the decontamination procedure), this fourth reported case suggests that the risk of iatrogenic CJD may have persisted in some patients treated after 1987, when grafts of cadaveric origin were totally abandoned.

Adult↗

Bullous scleroderma-like changes in chronic graft-versus-host disease.

Cutaneous graft-versus-host disease (GVHD) is the most common clinical setting for GVHD after bone marrow transplantation. Chronic cutaneous GVHD is categorized according to the type of skin lesions into lichenoid and sclerodermoid variants, but bullous scleroderma-like changes are exceptional. Recently, we studied a patient with these alterations. This is the second case described in the literature.

Adolescent↗

Relationship between meiotic spindle location with regard to the polar body position and oocyte developmental potential after ICSI.

BACKGROUND: The recent development of a computer-assisted polarization microscopy system (Polscope) with which the meiotic spindle can be visualized in living oocytes on the basis of its birefringence permits analysis of the meiotic spindles of oocytes subjected to ICSI. Previous studies have shown that the meiotic spindle is not always aligned with the first polar body (PB) in metaphase II human oocytes prepared for ICSI. In the present study, the relationship between the degree of meiotic spindle deviation from the first PB location and ICSI outcome was analysed. METHODS: Oocytes were divided into four groups according to the angle of meiotic spindle deviation from the PB position. The angle of deviation was 0-5 degrees, 6-45 degrees, 46-90 degrees and >90 degrees for groups I to IV respectively. RESULTS: The rates of normal [2 pronuclei (PN)] and abnormal (1PN or >2PN) fertilization did not differ between groups I, II and III. However, the rate of normal fertilization was lower among oocytes in which the meiotic spindle deviation angle was >90 degrees; this led to an increased proportion of tripronucleated zygotes that failed to extrude the second PB. When embryos developed from normally fertilized oocytes were evaluated on day 3 after ICSI, no relationship was found between the angle of meiotic spindle deviation and embryo quality. The meiotic spindle was not detected in only 9% of oocytes, and these showed a higher incidence of fertilization and cleavage abnormalities than did oocytes in which the spindle was detected. When oocytes at metaphase I after cumulus oophorus and corona radiata removal were matured in vitro, the meiotic spindle was detected in 53.8% of those that reached metaphase II. In these in-vitro-matured oocytes the meiotic spindle was always aligned with the first PB, suggesting that misalignment seen in those oocytes matured in vivo resulted from PB displacement during manipulations for cumulus and corona removal. CONCLUSION: High degrees of misalignment between the meiotic spindle and the first PB predict an increased risk of fertilization abnormalities. However, when normal fertilization had occurred, the cleavage potential of embryos developing from such oocytes was not impaired. These findings facilitate the selection of oocytes for ICSI in situations when the creation of supernumerary embryos is to be avoided.

Cell Nucleus↗

Topical use of cidofovir induced acute renal failure.

BACKGROUND: Cidofovir has antiviral activity against a wide spectrum of DNA viruses. Several small studies have focused on the efficacy of topical cidofovir in various viral-induced diseases. We report a systemic complication of such therapy. CASE REPORT: A bone marrow transplant recipient with chronic renal failure developed genital condylomas resistant to standard therapy. After topical cidofovir application (1% once daily for 5 days, then 4% for 12 days), the lesions improved while local erosions appeared. Acute renal failure with features of tubular acidosis occurred at day 19. Spontaneous recovery was observed after cidofovir withdrawal. CONCLUSION: We describe for the first time acute renal failure after topical cidofovir in an immunosuppressed patient with prior renal insufficiency. This method of administration should be avoided on abraded skin and should be carefully monitored.

Acute Kidney Injury↗

A stereo-photogrammetric method to measure the facial dysmorphology of children in the diagnosis of fetal alcohol syndrome.

In diagnosing a child with fetal alcohol syndrome (FAS), anthropometric measurements of the face are conventionally performed by highly trained dysmorphologists using a hand-held ruler. This renders the screening of large populations of children for the facial features characteristic of FAS very time-consuming and costly. This study proposes a new, cost-effective, and non-intrusive method to measure in three dimensions the facial dysmorphology of children using stereo-photogrammetry. The face of each child is photographed in a control frame simultaneously by a pair of high-resolution digital cameras mounted 1.04 m from the child and 0.26 m apart. Software has been developed to calibrate the images and to compute the three-dimensional object-space coordinates of any point on the face from a measurement of the point on each of the images. The palpebral fissure lengths, inner canthal-, and interpupillary distances of 44 subjects were measured in this manner independently by two investigators and compared with measurements obtained by clinical specialists in the conventional manner. There was found to be no statistically significant difference between palpebral fissure lengths determined using the two techniques (paired Student's t-test p-values are 0.29 and 0.18, respectively). It has also been demonstrated that facial measurements can be performed with greater consistency from a pair of stereo photographs than direct measurements from live subjects.

Anthropometry↗

Somatic and embryonic cell nucleus transfer into intact and enucleated immature mouse oocytes.

BACKGROUND: The aim of our study was to evaluate the possibility of embryonic or somatic cell haploidization after fusion with intact or enucleated immature oocytes which were subsequently cultured in vitro. Embryonic or somatic cell nuclei do not undergo premature chromosome condensation when fused to intact or enucleated immature oocytes whose maturation is prevented by dibutyryl cyclic AMP (dbcAMP). The presence of dbcAMP permits, however, the completion of DNA replication in somatic cell nuclei. METHODS AND RESULTS: The chromosomes condensed when the reconstructed cells were released from the dbcAMP block. When somatic or embryonic nuclei were introduced into intact immature meiotically competent oocytes and subsequently cultured their chromosomes assembled on a common spindle with meiotic chromosomes and proceeded through the meiotic-like division, judged according to the presence of the first polar body extruded. When embryonic cell nuclei were introduced into cytoplasts obtained from immature meiotically competent oocytes, polar bodies were extruded in about 75% of reconstructed cells but the metaphase plates were abnormal in almost all cases. When somatic cell nuclei were inserted into the above cytoplasts, polar bodies were extruded only very exceptionally and in these cells chromosomes were arranged in abortive metaphase plates. CONCLUSIONS: Our results suggest that somatic cell nuclei are unable to proceed through the reduction division (haploidization) when introduced into an immature oocyte meiotic cytoplasm.

Animals↗