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The aim of this study is to determine whether the balance problems experienced by Parkinson's disease (PD) patients may in part be due to dysfunctional processing of vestibular information, and to search for factors that may help predict the risk of falls. We evaluated the balance of 45 idiopathic PD patients and 20 healthy subjects by means of computerized dynamic posturography using sensory organization tests (SOT), rhythmic weight shift (RWS) tests and limits of stability (LOS) tests; and by the timed up-and-go (TUG) test. PD patients had poorer scores in the SOT than controls for overall balance and vestibular and visual inputs. They also performed worse in RWS and LOS tests, and were slower in performing the TUG test. Hoehn-Yahr stage did not correlate with vestibular input. Balance impairment in PD patients involves deteriorated processing of vestibular input, but this deterioration is independent of disease progression. Falls are related to PD patients' reduced limits of stability.

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The use of computerized dynamic posturogaphy (CDP) in the evaluation of patients with balance alterations not only allows quantification of the subject's capacity to maintain a stable centre of gravity, but also analysis of the degree to which the subject is able to use different types of sensory information. The present study investigated the possible use of CDP for clinical staging of vestibular diseases, specifically Meniere's disease (MD). We applied CDP sensory organization tests to 75 patients with definitive MD (AAO-HNS 1995 criteria). A total of 98 CDP sessions were included in the analysis, which focused on four CDP parameters specifically related to vestibular function (condition-5 score, condition-6 score, overall balance score, and VEST, a measure of the relative importance of vestibular information for maintenance of balance). We found a statistically significant relationship between audiometric hearing threshold and CDP scores, especially in patients with audiometrically advanced disease. In addition, CDP scores showed statistically significant variation with time elapsed since the last typical vertigo attack, suggesting that patients can be usefully grouped into three MD activity-level categories: recent post-attack (less than 1 week since last vertigo attack), late post-attack (1 week - 60 days since last attack), and inactive MD (more than 60 days since last attack). On the basis of these results, we propose expected ranges for each of the four CDP parameters in each of the three MD activity-level categories, allowing staging in terms of balance and posture. This staging system complements existing staging systems (based on audiometric criteria, and on subjective assessment of the severity of vertigo attacks and their implications for quality of life).

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Despite the spreading of Otologic care Units it is surprising the lack of comprehensive epidemiologic descriptions of patients attended in these Departments. A greater efficacy would be the result of better protocols designs and consequently a much better sanitary behaviour. We make a register of protocols and several aspects epidemiologic and diagnostical of our first consultations in the Unit during 1998. Were studied 595 cases, 320 women and 275 men, middle age was 49.91 years. From each one was controlled and analyzed the age, the sex, where they come from under the sanitary view-point, consult reason and diagnosis achieved.

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Multifrequency tympanometry scans pressures and frequencies from 226 to 2000 Hz to analyze the resonant frequency of the middle ear, which determines the balance between stiffness and mass. We studied 143 patients (a total of 200 ears) diagnosed as otosclerosis at the E.N.T. Service of Santiago de Compostela University Hospital Complex, and 136 control subjects. The mean age of patients was 47.7 years; women were predominant (female/male ratio 2.25:1). The mean duration of the disease was 10.4 years. Using the Virtual model 310 tympanometer, we calculated the resonant frequency through the susceptance tympanogram, corresponding to the minimal frequency at which the central notch of the tympanograrn was equal to or less than the negative tail. The mean resonant frequency was 1230 Hz, the tympanometric amplitude was 88.32 daPa, and the admittance of the middle ear was 0.63 cc. We confirmed an increase in the resonant frequency in patients with otosclerosis compared with normal subjects (1132.33 Hz), and a decrease in the admittance of the middle ear. The relation between the two values was significant.

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Multifrequency tympanometry studies consist of tympanography using probe tone frequencies ranging from 200 to 2000 Hz, improving the study of acoustic transmission through the tympano-ossicular system because then two components of admittance, conductance and susceptance, can be separated. The resonance frequency is the frequency at which mass and spring elements of the middle ear cancel each other out, leaving only the friction component. This measurement has been found to be more sensitive to the presence of pathologies that affect the tympano-ossicular system, such as otosclerosis and rheumatoid arthritis. It is necessary to know normal pattents of tympanometric parameters to improve the study of these diseases. Multifrequency tympanometry performed on 136 patients, 91 women and 45 men, age range 11-78 years. The mean resonant frequency of the middle ear was 1132.33 Hz, mean static admittance 0.76 dapa, and mean tympanometric amplitude 94.31 mmhos ac. Age showed no systematic effect of age on any of these measures in this population, and no significant association was found between static admittance or tympanometric amplitude and resonance frequency.

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Recent publications show an increase in the frequency of laryngeal carcinoma in women. Previous studies of patients in our health district (1875-1994) showed a male/female ratio of 56/1. However, a retrospective study of all laryngeal carcinomas diagnosed in a recent year (June 1997-May 1998) showed an overall male/female ratio of 10/1. Women are older at time of diagnosis than men (mean 70.33 years). None of the women was a regular drinker and only one smoked. Glottic location and absence of metastatic lymph node enlargement predominated at time of diagnosis.

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La timpanometría de multifrecuencia realiza un barrido de presiones y de frecuencias desde los 226 Hz a los 2. 000 Hz, permitiendo analizar la frecuencia de resonancia del oído medio, que determina el equilibrio entre la rigidez y la masa del mismo. Hemos estudiado 143 pacientes diagnosticados de otosclerosis en el Servicio de Otorrinolaringología del Complejo Hospitalario Universitario de Santiago de Compostela, con un total de 200 oídos estudiados, así como 136 personas normales como controles. La edad media de los pacientes al diagnóstico fue de 47,71 años, con un predominio del sexo femenino (relación mujer/varón de 2,25: 1), con una duración media de la enfermedad de 10,4 años. Utilizamos el timpanómetro Virtual modelo 310, calculando lafrecuencia de resonancia a través del timpanograma de susceptancia, correspondiendo a la mínima frecuencia en la que la muesca central del timpanograma es igual o inferior al extremo negativo del mismo. De esta forma, la frecuencia media de resonancia fue de 1.230 Hz, la amplitud timpanométrica de 88,32 daPa y la admitancia del oído medio de 0,63 cc. Hemos comprobado un incremento de la frecuencia de resonancia en los pacientes con otosclerosis, al compararlos con los valores de normalidad (1.132,33 Hz), así como una disminución de la admitancia del oído medio, existiendo entre los dos valores una relación significativa (AU)

Multifrequency tympanometry scans pressures and frequencies from 226 to 2000 Hz to analyze the resonant frequency of the middle ear, which determines the balance between stiffness and mass. We studied 143 patients (a total of 200 ears) diagnosed as otosclerosis at the E.N.T. Service of Santiago de Compostela University Hospital Complex, and 136 control subjects. The mean age of patients was 47.7 years; women were predominant (female/male ratio 2.25:1). The mean duration of the disease was 10.4 years. Using the Virtual model 310 tympanometer, we calculated the resonant frequency through the susceptance tympanogram, corresponding to the minimal frequency at which the central notch of the tympanograrn was equal to or less than the negative tail. The mean resonant frequency was 1230 Hz, the tympanometric amplitude was 88.32 daPa, and the admittance of the middle ear was 0.63 cc. We confirmed an increase in the resonant frequency in patients with otosclerosis compared with normal subjects (1132.33 Hz), and a decrease in the admittance of the middle ear. The relation between the two values was significant (AU)

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La timpanometría de multifrecuencia realiza un barrido timpanométrico entre 226 y 2000 Hz, mejorando el análisis de la transmisión del sonido a través del sistema tímpano-osicular, ya que posibilita el estudio independiente de los dos componentes de la admitancia del oído medio, la susceptancia y la conductancia. La frecuencia de resonancia del oído medio es la frecuencia en la que los elementos distensibles y de masa de la caja timpánica están en equilibrio; por tanto este parámetro se muestra útil en el estudio de patologías que alteren las características del sistema tímpano osicular como la otosclerosis y la artritis reumatoide. Es preciso conocer los parámetros de normalidad con el objeto de poderlos comparar con estas patologías. Realizamos la timpanometría de multifrecuencia a 136 pacientes entre 11 y 78 años. La frecuencia de resonancia media de oído medio fue de 1132.33 Hz, la admitancia estática media de 0, 76 dapa, y la amplitud timpanométrica media de 94,31 nmohs ac. Ninguno de estos parámetros mostró variaciones significativas en los distintos grupos de edad, y tampoco observamos asociación entre la frecuencia de resonancia de oído medio y la admitancia estática o la amplitud timpanométrica (AU)

Multifrequency tympanometry studies consist of tympanography using probe tone frequencies ranging from 200 to 2000 Hz, improving the study of acoustic transmission through the tympano-ossicular system because then two components of admittance, conductance and susceptance, can be separated. The resonance frequency is the frequency at which mass and spring elements of the middle ear cancel each other out, leaving only the friction component. This measurement has been found to be more sensitive to the presence of pathologies that affect the tympano-ossicular system, such as otosclerosis and rheumatoid arthritis. It is necessary to know normal pattents of tympanometric parameters to improve the study of these diseases. Multifrequency tympanometry performed on 136 patients, 91 women and 45 men, age range 11-78 years. The mean resonant frequency of the middle ear was 1132.33 Hz, mean static admittance 0.76 dapa, and mean tympanometric amplitude 94.31 mmhos ac. Age showed no systematic effect of age on any of these measures in this population, and no significant association was found between static admittance or tympanometric amplitude and resonance frequency (AU)

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Recientes publicaciones muestran un incremento en la incidencia del carcinoma de laringe en mujeres. Estudios previos llevados a cabo en pacientes de nuestra área sanitaria (1975-1994) muestran una relación hombre/mujer de 5611. Realizamos un estudio retrospectivo de todos los carcinomas de laringe diagnosticados en un año (junio, 1997-mayo, 1998), obteniendo una relación global hombre/mujer de 1 10/1. En las mujeres la edad al momento del diagnóstico es mayor que en los hombres (Media: 70,33 años), ninguna de ellas era bebedora habitual y sólo una era fumadora. Predomina la localización glótica y la ausencia de adenopatías metastásicas al momento del diagnóstico (AU)

Recent publications show an increase in the frequency of laryngeal carcinoma in women. Previous studies of patients in our health district (1875-1994) showed a male/female ratio of 56/1. However, a retrospective study of all laryngeal carcinomas diagnosed in a recent year (June 1997-May 1998) showed an overall male/female ratio of 10/1. Women are older at time of diagnosis than men (mean 70.33 years). None of the women was a regular drinker and only one smoked. Glottic location and absence of metastatic lymph node enlargement predominated at time of diagnosis (AU)

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We report here the identification of a human genomic sequence from the q27.2 region of the X chromosome which shows a high homology to the L-MYC proto-oncogene. This sequence is not the MYCL2 homology, previously mapped to the long arm of the X chromosome at q22-qter by Morton et al., as we located the MYCL2-processed gene in Xq22-23, using a panel containing a combination of hybrid DNA carrying different portions of the human X chromosome. Based on computer analysis, the MYC-like sequence (MYCL3) is 98.2% identical to a portion of exon 3 of the MYCL1 gene and maps to the Xq27.2 region, between the DXS312 and DXS292 loci.

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Eleven balanced X-autosome translocations associated with premature ovarian failure (POF) were mapped to a YAC contig spanning most of Xq21 and constructed between the DXS223 and DXS1171 loci. The contig corresponds to a genomic region of about 15 Mb and contains the whole X-Y homologous region. The most proximal and most distal breakpoints associated with POF were mapped 15 Mb apart. The remaining breakpoints were localized along this large region, in the X-specific and in the X-Y homologous region. Four of the YACs contained two breakpoints in the same or in flanking STS intervals. Our results confirm the cytological findings and suggest that a minimum number of eight different genes in Xq21 may be involved with ovary development. Interruption of such loci could be the cause of POF.

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The human X chromosome is associated with a large number of disease phenotypes, principally because of its unique mode of inheritance that tends to reveal all recessive disorders in males. With the longer term goal of identifying and characterizing most of these genes, we have adopted a chromosome-wide strategy to establish a YAC contig map. We have performed > 3250 inter Alu-PCR product hybridizations to identify overlaps between YAC clones. Positional information associated with many of these YAC clones has been derived from our Reference Library Database and a variety of other public sources. We have constructed a YAC contig map of the X chromosome covering 125 Mb of DNA in 25 contigs and containing 906 YAC clones. These contigs have been verified extensively by FISH and by gel and hybridization fingerprinting techniques. This independently derived map exceeds the coverage of recently reported X chromosome maps built as part of whole-genome YAC maps.

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We performed a focused chromosome analysis on the HL60 cell line by multicolor fluorescence in situ hybridization (FISH), using probes for the unequivocal identification of specific chromosome regions and subregions. The purpose of this karyotypic re-evaluation was to confirm and to characterize in more detail chromosome rearrangements already identified by means of classic cytogenetic approaches and recurrently detected from the initial establishment of the cell line. The observations reported may help reassess the potential of the HL60 cell line in understanding the molecular events underlying the non-random karyotype alterations associated with acute myeloid leukemias (AML).

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The interaction of topoisomerase II (topo II) with human ribosomal DNA (rDNA) was investigated in vivo using the antitumoral drug VM26, a specific inhibitor of topo II, that stabilizes the transient cleavable complex. rDNA-protein complexes isolated from nucleoli of TG cells were analyzed for double strand breaks with probes that covered almost all intergenic transcribed spacer (IGS) and all transcribed sequences of tandem repeat ribosomal DNA genes. Preferential cleavage sites were present in only a part of nucleolar rDNA, i.e., the transcribed region. Proteins, purified from the same complexes, were analyzed by Western-blot and stained by an antiserum against both topo II forms, showing the presence of topo II beta.

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The use of integrated mapping strategies involving bacterial, yeast, and rodent cells as hosts simplifies the construction of maps, which combine long-range order, high resolution, and easy access to the cloned DNA. Radiation-fusion hybrids offer a specially powerful long-range mapping system for human chromosomes. We describe here techniques for establishing a radiation-fusion hybrid map of Chromosome (Chr) 21q and its integration with local information on YAC and cosmid positions.

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This study centers on marker chromosomes carrying expanded chromosomal regions which were observed in two independent derivatives of the AA12 murine fibrosarcoma line, the 10(-3) M MTX-res H2 and the 5 x 10(-7) M MTX-res E. Previous characterization of the marker chromosomes of MTX-res variants showed their common derivation from a marker chromosome (m) of the parental line, endowed with two interstitial C-bands. Cytogenetic evidence pointed to one C-band of m as the site involved in the chromosomal rearrangements leading to the HSR/ASR chromosomes. ISH of a 3H-labeled satellite DNA probe allowed satellite sequences flanking the HSR/ASR in the marker chromosomes, where the C-band was no longer visible, to be detected. FISH experiments using biotinylated DHFR and satellite DNA probes showed that the respective target sequences are contiguous in new marker chromosomes. They also allowed inter- and intrachromosomal rearrangements to be seen at DHFR amplicons and satellite sequences. Double-color FISH using digoxygenated satellite DNA and biotinylated pDHFR7 showed that in a marker chromosome from the H2 cell line the two target sequences are not only adjacent, but closer than 3 Mb, as indicated by overlapping of the different fluorescence signals given by the two probes. Another marker chromosome in the E variant was shown to display a mixed ladder structure consisting of a head-to-head tandem of irregularly-sized satellite DNA blocks, with two symmetrical interspersed DHFR clusters.

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We have developed a way to fit yeast artificial chromosomes (YACs) with markers that permit the selection of stably transformed mammalian cells, and have determined the fate and expression of such YACs containing the genes for human ribosomal RNA (rDNA) or glucose-6-phosphate dehydrogenase (G6PD). The YACs in the yeast cell are "retrofitted" with selectable markers by homologous recombination with the URA3 gene of one vector arm. The DNA fragment introduced contains a LYS2 marker selective in yeast and a thymidine kinase (TK) marker selective in TK-deficient cells, bracketed by portions of the URA3 sequence that disrupt the endogenous gene during the recombination event. Analyses of transformed L-M TK- mouse cells showed that YACs containing rDNA or G6PD were incorporated in essentially intact form into the mammalian cell DNA. For G6PD, a single copy of the transfected YAC was found in each of two transformants analyzed and was fully expressed, producing the expected human isozyme as well as the heterodimer composed of the human gene product and the endogenous mouse gene product.

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One hundred twenty-seven yeast strains with artificial chromosomes containing Xq24-Xqter human DNA were obtained starting from a human/hamster somatic cell hybrid. The clones were characterized with respect to their insert size, stability, and representation of a set of Xq24-Xqter DNA probes. The inserts of the clones add up to 19.3 megabase (Mb) content, or about 0.4 genomic equivalents of that portion of the X chromosome, with a range of 40-650 kb in individual YACs. Eleven clones contained more than one YAC, the additional ones usually having hamster DNA inserts; the individual YACs could be separated by extracting the total DNA from such strains and using it to retransform yeast cells. One of the YACs, containing the probe for the DXS49 locus, was grossly unstable, throwing off smaller versions of an initial 300-kb YAC during subculture; the other YACs appeared to breed true on subculture. Of 52 probes tested, 12 found cognate YACs; the YACs included one with the glucose-6-phosphate dehydrogense gene and another containing four anonymous probe sequences (DX13, St14, cpx67, and cpx6). Xq location of YACs is being verified by in situ hybridization to metaphase chromosomes, and fingerprinting and hybridization methods are being used to detect YACs that overlap.

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The technique used for DNA determination in tumoral cells from carcinomas of head and neck is described. Results obtained are commented on as is too the future of this technique for the better understanding of the behavior of the tumor and consequently of its treatment.

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Human ribosomal DNA has been inferred to be organized in tandem repeat units of 44 kb, of which only 13 kb is transcribed into preribosomal RNA. Unfortunately, it has remained difficult to examine the intact repeat structure directly, because even a single repeat unit is too large to be accommodated in conventional cloning systems. Here we report the isolation of intact repeat units using yeast artificial chromosomes as a cloning tool. With a spacer sequence specific to human ribosomal DNA used as a probe, 27 clones were identified among 17,000 YACs (about 0.7 genomic equivalent of total human DNA). Fourteen clones contained only a small portion of rDNA; the other 13 contained most or all of the rDNA repeat unit, and 8 of those were studied in further detail. They contained 1 to 1.5 repeat units of rDNA with all of the expected EcoRI and HindIII fragments. These clones provide possible starting material for the analysis of expression of a single unit of rDNA. Unexpectedly, however, only the four smaller clones (70 to 90 kb) were completely composed of standard rDNA sequences; four larger clones (up to 950 kb in length) contained additional "non-rDNA" sequences, at either one or both ends of the repeat unit. Analysis of these atypical rDNA clones suggests that their inserts either are scattered in the genome or are localized in a nucleolar organizer region that is more complex than previously recognized.

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