PubMed Health⌕ Search

Biomedical subjects

J M Millán

Publications and source records attributed to J M Millán.

At least 19 recordsLinked to original sources
PubMed2006

Mutation profile of the MYO7A gene in Spanish patients with Usher syndrome type I.

Usher syndrome type I is the most severe form of Usher syndrome. It is an autosomal recessive disorder characterized by profound congenital sensorineural deafness, retinitis pigmentosa, and vestibular abnormalities. Mutations in the myosin VIIA gene (MYO7A) are responsible for Usher syndrome type 1B (USH1B). This gene is thought to bear greatest responsibility for USH1 and, depending on the study, has been reported to account for between 24% and 59% of USH1 cases. In this report a mutation screening of the MYO7A gene was carried out in a series of 48 unrelated USH1 families using single strand conformation polymorphism analysis (SSCP) and direct sequencing of those fragments showed an abnormal electrophoretic pattern. Twenty-five mutations were identified in 23 out of the 48 families studied (47.9%). Twelve of these mutations were novel, including five missense mutations, three premature stop codons, three frameshift, and one putative splice-site mutation. Based on our results we can conclude there is an absence of hot spot mutations in the MYO7A gene and that this gene plays a major role in Usher syndrome.

DNA Mutational Analysis↗
PubMed2006

Aneurysm re-rupture during computed tomography angiography.

Re-rupture of cerebral aneurysms during conventional angiography, demonstrated by contrast leakage into the extravascular space, is well known and well documented. However, the occurrence of this complication during computed tomography (CT) angiographic examinations has rarely been published despite its extensive use. We present the clinical and radiological features of a rebleeding event during a CT angiographic study. No hemodynamic or contrast-related factors can be evoked predisposing to he occurrence of this complication during this imaging technique. This, along with the short study time, may explain the rarity of this coincidence.

Aneurysm, Ruptured↗
PubMed2006

Identification of 14 novel mutations in the long isoform of USH2A in Spanish patients with Usher syndrome type II.

Mutations in USH2A gene have been shown to be responsible for Usher syndrome type II, an autosomal recessive disorder characterised by hearing loss and retinitis pigmentosa. USH2A was firstly described as consisting of 21 exons, but 52 novel exons at the 3' end of the gene were recently identified. In this report, a mutation analysis of the new 52 exons of USH2A gene was carried out in 32 unrelated patients in which both disease-causing mutations could not be found after the screening of the first 21 exons of the USH2A gene. On analysing the new 52 exons, fourteen novel mutations were identified in 14 out of the 32 cases studied, including 7 missense, 5 frameshift, 1 duplication and a putative splice-site mutation.

Adolescent↗
PubMed2004

Phase II trial of cisplatin and capecitabine in patients with squamous cell carcinoma of the head and neck, and correlative study of angiogenic factors.

The combination of cisplatin and capecitabine was evaluated in patients with recurrent or unresectable squamous cell carcinoma of the head and neck (HNSCC), and outcome parameters were correlated with the expression of thymidine phosphorylase (TP), thymidilate syntetase (TS), vascular endothelial growth factor receptor (VEGFR) 1-3, and microvessel density (MVD). Patients with recurrent or unresectable HNSCC were eligible if they had received prior neoadjuvant chemotherapy, concurrent chemo-radiotherapy, or no prior systemic therapy. Patients received cisplatin (75 mg m(-2) day 1), and capecitabine (2000 mg m(-2) day 1-14) every 3 weeks. A total of 41 patients received 194 cycles. In all, 16 complete responses (39%) and 12 partial responses (29%) were documented, for an overall response rate of 68% (95% CI, 53-80%). Grade 3-4 uncomplicated neutropenia was documented in five subjects. Asthenia, anorexia, hand-foot syndrome, and constipation were the most frequent nonhaematologic events. Median progression-free and overall survival were 6.4 and 12.6 months. Cytoplasmic TP expression was more prevalent in patients with a laryngeal location vs other, and in patients with a recurrence vs primary disease. Microvessel density count was higher in patients with recurrent vs primary disease. The combination of cisplatin and capecitabine is effective in recurrent or unresectable HNSCC, and shows a manageable toxicity.

Adult↗
PubMed2004

Mutation screening of USH3 gene (clarin-1) in Spanish patients with Usher syndrome: low prevalence and phenotypic variability.

Usher syndrome type III is an autosomal recessive disorder clinically characterized by the association of retinitis pigmentosa (RP), variable presence of vestibular dysfunction and progressive hearing loss, being the progression of the hearing impairment the critical parameter classically used to distinguish this form from Usher syndrome type I and Usher syndrome type II. Usher syndrome type III clinical subtype is the rarest form of Usher syndrome in Spain, accounting only for 6% of all Usher syndrome Spanish cases. The gene responsible for Usher syndrome type III is named clarin-1 and it is thought to be involved in hair cell and photoreceptor cell synapses. Here, we report a screening for mutations in clarin-1 gene among our series of Usher syndrome Spanish patients. Clarin-1 has been found to be responsible for the disease in only two families: the first one is a previously reported family homozygous for Y63X mutation and the second one, described here, is homozygous for C40G. This accounts for 1.7% of Usher syndrome Spanish families. It is noticeable that, whereas C40G family is clinically compatible with Usher syndrome type III due to the progression of the hearing loss, Y63X family could be diagnosed as Usher syndrome type I because the hearing impairment is profound and stable. Thus, we consider that the progression of hearing loss is not the definitive key parameter to distinguish Usher syndrome type III from Usher syndrome type I and Usher syndrome type II.

Adolescent↗
PubMed2002

Giant cell reparative granuloma of the occipital bone.

Giant cell reparative granuloma (GCRG) is a non-neoplastic fibrous lesion with unevenly distributed multinucleated giant cells, areas of osseous metaplasia and hemorrhage. The small bones of the hands and feet are the most common sites, followed by the vertebral bodies and craniofacial bones. In the craniofacial bones GCRG has been reported in the temporal bone, in the frontal bone and paranasal sinus. However, to the best of our knowledge no case has been reported in the occipital bone. We report on the imaging findings and pathological features of a GCRG of the occipital bone and discuss the differential diagnosis of this entity in this particular location, especially with giant cell tumor because of the therapeutic and prognostic implications.

Bone Diseases↗
PubMed2002

Molecular genetic analysis of HLA-DR and -DQ alleles in Spanish patients with melanoma.

Controversial data have been reported about HLA alleles and susceptibility to melanoma. The relationship between distribution of HLA alleles in patients with melanoma and susceptibility to tumour was analysed, to study the possible correlation between HLA class II DQA1, DQB1 and DRBI genes and melanoma in a Spanish population. Genomic DNA from 82 patients with melanoma and 367 random healthy donors, from the same geographic area, were typed by PCR-SSP (sequence specific primers). The patients were also divided into different groups according to the age and presence of cancer relatives, and compared with the controls. None of these HLA class II alleles showed significant positive or negative associations with either the overall population of patients with melanoma or the considered subgroups. Moreover, values for relative risk of DQB1*0301, DQB1*0302, DQB1*0303, DQB*05, DQA1*0401, DQA1*0101/0104 and DRB*08, which have been reported to be increased or decreased in patients with melanoma, were very low and of no statistical significance. Our results indicate that HLA class II alleles may not contribute to a strong susceptibility to melanoma in the Spanish population, although further studies on larger series are needed to corroborate this. Key words:

Adolescent↗
PubMed2002

Induction chemotherapy with paclitaxel, cisplatin and 5-fluorouracil for squamous cell carcinoma of the head and neck: long-term results of a phase II trial.

BACKGROUND: The aim of this study was to evaluate the efficacy and toxicity of a combination of paclitaxel, cisplatin and 5-fluorouracil (PPF) as induction chemotherapy in patients with locally advanced squamous cell carcinoma of the head and neck (SCCHN). METHODS: Seventy patients with previously untreated stage III-IV SCCHN were included in this phase II trial. Induction treatment consisted of a maximum of three outpatient courses of paclitaxel 175 mg/m(2) as a 3-h infusion on day 1, cisplatin 100 mg/m(2) on day 2, and 5-fluorouracil (5-FU) 500-750 mg/m(2)/day as a 24-h continuous infusion on days 2-6, repeated every 3 weeks. The 5-FU dose was reduced from 750 mg/m(2)/day to 500 mg/m(2)/day due to the excessive toxicity observed in the first 14 patients enrolled. Local treatment consisted of radiotherapy and/or surgery. RESULTS: Two-hundred-and-one cycles were administered to 70 patients. The main toxicities of PPF were neutropenia (grade 4, 14%; febrile neutropenia, 4%), peripheral neuropathy (grade 2-3, 14%) and catheter-associated venous thrombosis (7%). There were three early deaths (two from neutropenic sepsis and one from pulmonary embolism), and 13 patients required hospitalization due to toxicity. Other side effects included mucositis, anorexia, diarrhea, myalgias and alopecia. The overall response rate to PPF was 88%, including 59% complete responses (CR) and 29% partial responses. The CR rates at the primary tumor and neck lymph nodes were 74% and 62%, respectively. With a median follow-up of 51 months (range 40-63 months), the estimated 5-year time-to-disease progression and overall survival rates were 56% and 44%, respectively. CONCLUSIONS: The PPF regimen has major antitumor activity and is associated with manageable toxicity as induction treatment in SCCHN patients. The high complete response rate and favorable long-term outcome justify further evaluation of this chemotherapy combination.

Adult↗
PubMed2001

Localization of non-specific X-linked mental retardation gene (MRX73) to Xp22.2.

Clinical and molecular studies are reported on a family (MRX73) of five males with non-specific X-linked mental retardation (XLMR). A total of 33 microsatellite and RFLP markers was typed. The gene for this XLMR condition was been linked to DXS1195, with a lod score of 2.36 at theta = 0. The haplotype and multipoint linkage analyses suggest localization of the MRX73 locus to an interval of 2 cM defined by markers DXS8019 and DXS365, in Xp22.2. This interval contains the gene of Coffin-Lowry syndrome (RSK2), where a missense mutation has been associated with a form of non-specific mental retardation. Therefore, a search for RSK2 mutations was performed in the MRX73 family, but no causal mutation was found. We hypothesize that another unidentified XLMR gene is located near RSK2.

Chromosome Mapping↗
PubMed2001

DNA interstrand cross-linking efficiency and cytotoxic activity of novel cadmium(II)-thiocarbodiazone complexes.

We have prepared mono- and binuclear complexes of Zn(II) and Cd(II) with bis(2-pyridyl aldehyde) thiocarbodiazone (H(2)L(1)) and bis(methyl 3-pyridyl ketone) thiocarbodiazone (H(2)L(2)). Cytotoxicity data against the ovarian tumor cell line A2780cisR (acquired resistance to cisplatin) indicate that the mononuclear complex Cd/H(2)L(2) (1) and the binuclear complex Cd(2)/H(2)L(1) (4) are able to circumvent cisplatin resistance and that their cytotoxic activity does not substantially vary after depletion of intracellular levels of glutathione. Moreover, DNA binding studies show that complexes 1 and 4 have higher efficiency than cisplatin at forming DNA interstrand cross-links in both naked pBR322 plasmid and A2780cisR cellular DNA. Interestingly, the thiocarbodiazone ligands alone do not show the biological properties of complexes 1 and 4. Altogether these results suggest that DNA interstrand cross-link formation by compounds 1 and 4 might be related with their cytotoxic activity in cisplatin-resistant cells. We think that compounds 1 and 4 may represent a novel structural lead for the development of cadmium cytotoxic agents capable of improving antitumor activity in cisplatin-resistant tumors.

Antineoplastic Agents↗
PubMed2001

Identification of novel RP2 mutations in a subset of X-linked retinitis pigmentosa families and prediction of new domains.

X-linked Retinitis Pigmentosa (XLRP) shows a huge genetic heterogeneity with almost five distinct loci on the X chromosome. So far, only two XLRP genes have been identified, RPGR (or RP3) and RP2, being mutated in approximately 70% and 10% of the XLRP patients. Clinically there is no clearly significative difference between RP3 and RP2 phenotypes. In the attempt to assess the degree of involvement of the RP2 gene, we performed a complete mutation analysis in a cohort of patients and we identified five novel mutations in five different XLRP families. These mutations include three missense mutations, a splice site mutation, and a single base insertion, which, because of frameshift, anticipates a stop codon. Four mutations fall in RP2 exon 2 and one in exon 3. Evidence that such mutations are different from the 21 RP2 mutations described thus far suggests that a high mutation rate occurs at the RP2 locus, and that most mutations arise independently, without a founder effect. Our mutation analysis confirms the percentage of RP2 mutations detected so far in populations of different ethnic origin. In addition to novel mutations, we report here that a deeper sequence analysis of the RP2 product predicts, in addition to cofactor C homology domain, further putative functional domains, and that some novel mutations identify RP2 amino acid residues which are evolutionary conserved, hence possibly crucial to the RP2 function.

Amino Acid Sequence↗
PubMed2001

Parosteal osteosarcoma of the skull.

Parosteal osteosarcoma of the skull is a distinct surface bone tumor, with a better prognosis than conventional osteosarcoma. The most common location is on the surface of the distal femur which accounts for 46-66% of the cases. The presentation in the skull is uncommon and there are few cases reported in the literature. We describe the case of a man who developed a parosteal osteosarcoma arising from the occipital bone with extension to the parietal bone. The patient was operated and had a complete tumor resection.

Cerebral Angiography↗
PubMed2001

Trisomy rescue by postzygotic unbalanced (X;14) translocation in a girl with dysmorphic features.

In this report we present the clinical features and molecular and cytogenetic findings in a female with partial trisomy 14q. Molecular and cytogenetic studies allowed us to determine that the extra 14q material (of paternal origin) was translocated postzygotically onto the maternal X chromosome. Consequently, only the derivative X chromosome was inactivated, although inactivation apparently did not spread over the entire chromosome 14q. This partial inactivation makes the present case unusual, giving rise to phenotypic features absent in other patients with partial trisomy 14q, typically restricted to the distal part of the chromosome.

Blotting, Southern↗
PubMed2000

Fatal cerebral venous sinus thrombosis as major complication of metastatic cervical mass: computed tomography and magnetic resonance findings.

Cerebral venous sinus thrombosis is an uncommon but potentially lethal condition, with mortality between 5.5-30 per cent. It was previously associated with infections of the orbit, mastoid or face, but, after the advent of antibiotics, the most common causes include neoplasms, dehydration, oral contraceptives, coagulopathies, collagen diseases, and pregnancy and the puerperium. We report a case of fatal cerebral venous sinus thrombosis in a 68-year-old patient with a metastatic cervical mass, who developed internal jugular vein thrombosis that progressed cranially to transverse and sagittal sinus thrombosis.

Aged↗
PubMed2000

Prevalence of 2314delG mutation in Spanish patients with Usher syndrome type II (USH2).

The Usher syndrome (USH) is a group of autosomal recessive diseases characterized by congenital sensorineural hearing loss and retinitis pigmentosa. Three clinically distinct forms of Usher syndrome have so far been recognized and can be distinguished from one another by assessing auditory and vestibular function. Usher syndrome type II (USH2) patients have congenital moderate-to-severe nonprogressive hearing loss, retinitis pigmentosa, and normal vestibular function. Genetic linkage studies have revealed genetic heterogeneity among the three types of USH, with the majority of USH2 families showing linkage to the USH2A locus in 1q41. The USH2A gene (MIM 276901) has been identified: three mutations, 2314delG, 2913delG, and 4353-54delC, were initially reported in USH2A patients, the most frequent of which is the 2314delG mutation. It has been reported that this mutation can give rise to typical and atypical USH2 phenotypes. USH2 cases represent 62% of all USH cases in the Spanish population, and 95% of these cases have provided evidence of linkage to the USH2A locus. In the present study, the three reported mutations were analyzed in 59 Spanish families with a diagnosis of USH type II. The 2314delG was the only mutation identified in our population: it was detected in 25% of families and 16% of USH2 chromosomes analyzed. This study attempts to estimate the prevalence of this common mutation in a homogeneous Spanish population.

Alleles↗
PubMed1999

Identification of three novel mutations in the MYO7A gene.

Three new mutations in the myosin VIIA gene involved in the pathogenesis of Usher syndrome type Ib are reported. These mutations are K1080X in exon 25, E1170K in exon 28, and Y1719C in exon 37. It is presumed that these mutations are involved in the Usher syndrome Ib phenotype.

Base Sequence↗