Biomedical subjects

P Quesada

Publications and source records attributed to P Quesada.

At least 37 records · Page 2Linked to original sources

PubMed1999

[Treatment of idiopathic facial paralysis: corticoids versus acyclovir versus empirical treatment].

Bell's palsy has no specific treatment because its cause is still debated. The most widely accepted theory postulates an immunovirological origin consisting of the reactivation of a silent herpesvirus on the geniculate ganglion. We studied three groups of patients with Bell's palsy who received different treatments in an attempt to discern differences in evolution between treatment groups.

Acyclovir↗

PubMed1998

Poly(ADP-ribose) binding properties of histone H1 variants.

Using a poly(ADP-ribose) binding assay on protein blots we examined the ability of rat testis histone H1 variants to establish non-covalent interactions with the polymer. All the H1 variants bound ADP-ribose polymers; the binding was salt resistant and highly specific, occurring even in the presence of a large excess of competitor DNA. A comparison among the H1 variants showed that H1t has the highest affinity for poly(ADP-ribose). Long and branched poly(ADP-ribose) molecules were found to be preferentially involved in the interaction with the histone variants. The results further corroborate the concept that non-covalent interactions of poly(ADP-ribose) with target proteins may constitute an important mechanism to modulate chromatin structure.

DNA↗

PubMed1998

[Recurrent peripheral facial paralysis. Our case load from 1995].

Of 117 cases of peripheral facial palsy seen in our emergency room in 1995, 10 (8.5%) were relapses. Seven were males and 3, females. Mean age at the first appearance was 23.6 years. The mean interval between the first facial palsy and the first recurrence was 10.1 years, and between the first and second recurrence, 4.6 years. Five of the 10 patients (50%) had a second recurrence. Two of the 10 patients (20%) had a family history of facial palsy. Only 1 (10%) was diabetic. Seven of 10 patients achieved a complete functional recovery and 3 had sequelae. Computed tomography was normal in every patient. In our series, a family history of facial palsy and low ENoG results were related with a poorer prognosis. ENoG scan was used as a prognostic and follow-up factor.

Adolescent↗

PubMed1998

[Omeprazole: a new treatment for paranasal sinus polyps in Widal syndrome. Preliminary study].

A preliminary report is made of the potential therapeutic effect of omeprazol in reducing nasosinusal polyps. This study is based on the empirical observation of nasal airflow improvement in patients suffering from nasosinusal polyposis after administering omeprazol. Different phases of the study suggested that patients with Widal's syndrome benefited the most. Based on the results of this study, we have undertaken a randomized, parallel, double-blind, placebo-controlled clinical trial.

Anti-Inflammatory Agents↗

PubMed1998

[Nitric oxide synthase activity in nasal mucosa].

Nitric oxide (NO) plays an important regulatory role in airway function and seems to be implicated in the pathophysiology of several airway diseases. We studied the presence of NO synthase activity in human nasal mucosa and nasal polyp tissues obtained from patients undergoing septoplasty or polypectomy, respectively. NO synthase activity was quantified in tissue homogenates using citrulline release assay and was located in tissue sections using NADPH-diaphorase histochemistry. The results indicated that nasal polyps contain higher levels of total NO synthase activity than nasal mucosa tissue. In addition, nasal polyps contained mainly inducible NO synthase activity whereas all NO synthase activity detected in the nasal mucosa was in constitutive form. In both cases, NO synthase activity was localized in epithelial cells. In view of these results, we conclude that NO may be an important inflammatory mediator in the respiratory system and that the epithelium may be a source of NO production.

Adult↗

PubMed1998

[Second primary tumors in patients with laryngeal neoplasms].

A cohort epidemiologic study of second primary tumours appeared in patients diagnosed of laryngeal neoplasms, between years 1988 and 1990, and a follow-up term of 5 years, is presented. An statistical analysis of several data to define a possible high risk group for developing primary tumours was performed for all patients.

Adolescent↗

PubMed1997

Endoscopic evolution of laryngeal injuries caused by translaryngeal intubation.

Despite improvements in tube design and materials, the longer survival rates of critically ill patients make laryngeal and tracheal lesions still common following prolonged translaryngeal intubation. The time of intubation is almost the only factor employed in deciding whether or not tracheotomy has to be performed. Some patients will not develop laryngeal lesions afer long intubation periods, whereas some already have clinical symptoms after short periods of time. If the conditions of the larynx and trachea could be assessed before irreversible complications take place, then timing of tracheotomy could be individualized to avoid laryngeal stenosis as well as unnecessary tracheostomies. We present the preliminary results of an endoscopic study of the early laryngeal changes that take place during translaryngeal intubation. The method of exploration is explained and tissue changes seen and their evolution after extubation are described, emphasizing those that could have a predictive value.

Adolescent↗

PubMed1997

[Anomalies of the facial nerve].

An anomaly of the tympanic segment of the facial nerve in an adult cadaver specimen is reported. The second portion of the facial nerve crossed between the stapedal pillars. The rarity of this anomaly, particularly in a well constituted temporal bone, is discussed.

Facial Nerve↗

PubMed1997

[Mucoceles. Review of reported cases in the last 15 years].

The AA. present a retrospective study of all instances diagnosed as mucoceles in the last 15 years (1978-1993) at General University Hospital, Valle de Hebrón. Age of occurrence and sex, foregoing pathologic history, clinical picture, diagnostic tests, treatment and subsequent course of the condition are duly considered and appraised. Our attempt has been to stablish a diagnostic clinical pattern of these conditions, which generally are uncovered through its complications.

Adolescent↗

PubMed1997

[Microbiological and auditory analysis before and after topical treatment of chronic suppurative otitis media without cholesteatoma].

The AA. present a study microbiologic and auditive as well about chronic, suppurative otitis media non cholesteatomatous, before and after topical treatment. They contemplate 178 samples of chronic discharging ears which were treated with gentamycin 0.3 %, instillation 5 drops every 8 hours, during 10 days. Twelve days later were newly assessed both the otorrhea and the cochleovestibular picture. Germs most frequently detected: Gram-negative 61.6 %, Gram-positive 19.8 %, associated flora 6.4 % and mycosis 2.2 %, among other. Clinic healing accounted for 97.29 % and not significative differences scored pre--and post-treatment.

Administration, Topical↗

PubMed1996

Poly(ADPribosyl)ation system in transcriptionally active rat testis chromatin fractions.

The rat testis chromatin fractions (soluble, S, and insoluble, P) were prepared by mild digestion of nuclei with DNAase I. They appeared to be different in specific biochemical features such as their transcriptional competence and protein patterns, the latter indicating according to results previously obtained, that the testis-specific H1t is preferentially associated to the soluble fraction, whereas the other H1 variants are localized in the pellet. S and P chromatins also differed in the distribution of the poly(ADP-ribosyl)ating system, (poly(ADP-ribose)polymerase, reaction product and acceptor proteins), detected by incubating nuclei with 32P-NAD. The 32P-modified H1s and core histones of both fractions, known as specific ADPribose target proteins, were separated by high performance liquid chromatography and it was demonstrated that the H1 variants from S and P are differently ADPribosylated, being H1t always the best acceptor, and that most of the ADPribosylated variants were solubilized after DNase I treatment. The further digestion of P chromatin with the nuclease produced a fraction (pP) devoid of most DNA, but particularly enriched in transcriptionally competent tracts. The low DNA content of pP chromatin, which reflects the typical feature of a nuclear matrix, corresponded to a relevant poly(ADPribosyl)ation, the highest as compared to S and P fractions. Moreover, long and branched chains of poly(ADP-ribose) were found associated to pP sample which resemble the products determined in the soluble chromatin.

Animals↗

PubMed1996

Poly(ADPribosyl)ation system in rat germinal cells at different stages of differentiation.

In order to study the possible functional relationship between poly(ADP-ribosyl)ation and spermatogenesis, the three main germinal cell types have been isolated and characterized as haploid spermatids and diploid and tetraploid spermatocytes. Purified germinal cell populations and rats of different age were used for activity-, immuno-, and Northern blot experiments, to determine at which level poly(ADPR)polymerase (PARP) is regulated at various stages of spermatogenesis. Poly(ADPR)glycohydrolase (PARG) activity was also determined, as was the subcellular distribution of both PARP and PARG enzymes. The results show that the maximum of both PARP amount and PARP activity can be detected on tetraploid spermatocytes which undergo meiotic division, whereas PARG activity does not differ in germinal cells; the cytoplasmic form of this enzyme is prevalent in testis. Moreover, a difference in timing was observed in maximal level between PARP expression, determined on testis from 60-day-old rats, and PARP activity, detected on testis from 30-day-old animals. It seems that different mechanisms modulate the poly(ADPribosyl)ation system during spermatogenesis. Regulation of the poly(ADPribose) turnover, variations of PARP amount, as well as changes of PARP transcription level, seem to accompany germinal cell differentiation, possibly being implicated in DNA replication, repair, and transcription.

Aging↗

PubMed1996

Frequency content of normal and diabetic plantar pressure profiles: implications for the selection of transducer sizes.

How small do pressure transducers need to be in order to faithfully measure the plantar pressure profiles (PPPs) under normal and diabetic feet? In this study, pressures were collected from five diabetic and six non-diabetic subjects using a commercial measurement system with 25 mm2 transducers. Discrete Fourier Transform techniques were then used to determine (i) the spatial frequency content of diabetic and non-diabetic PPPs, and (ii) the effects of quadrupling the transducer area (from 5 mm x 5 mm to 10 mm x 10 mm). When the data were filtered to represent the effects of using 10 mm x 10 mm transducers, it was found that the ensuing reductions in peak pressure in the toe region (50 kPa) were significantly greater than in all other regions of the foot (p < 0.05). There was a significant correlation between pressure underestimations and measured peak pressures in the metatarsal regions. Based on data collected with 25 mm2 transducers it was concluded that transducer sizes greater than 6.36 mm x 6.18 mm (medio-lateral and antero-posterior directions) would result in sub-optimal sampling of PPPs.

Adult↗

PubMed1996

Differential activity of nitric oxide synthase in human nasal mucosa and polyps.

Nitric oxide (NO) plays an important regulatory role in airway function and seems to be implicated in the pathophysiology of several airway diseases. To better understand the involvement of NO in the upper airways, we examined the presence of nitric oxide synthase (NOS) activity in human nasal mucosa and nasal polyp tissues. Nasal mucosa was obtained from seven patients undergoing septoplasty, and nasal polyps came from nine patients following polypectomy. NOS activity was quantified in tissue homogenates using the citrulline release assay and localized in tissue sections using reduced nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase histochemistry. The results showed that nasal polyps (n = 9) contained higher levels of total NOS activity (mean +/- SD 5.94 +/- 5.71, range 1.29-18.0 pmol.min-1.mg protein) than nasal mucosa tissues (n = 7) (0.28 +/- 0.22, range 0.01-0.57 pmol.min-1.mg protein). In addition, nasal polyps mainly contained inducible NOS activity (4.67 +/- 4.57, range 1.23-15.5 pmol.min-1.mg protein) whereas in nasal mucosa all NOS activity detected was in constitutive form. In both cases, NOS activity was localized in the epithelial cells. Since NO synthase is induced in inflamed upper airways, we conclude that NO may be an important inflammatory mediator in the respiratory system and that the epithelium may be a source of NO production in the human upper airways.

Adult↗

PubMed1995

ADP-ribosylation reactions in Sulfolobus solfataricus, a thermoacidophilic archaeon.

An ADP-ribosylating system was detected in a crude homogenate from Sulfolobus solfataricus, a thermophilic archaeon, optimally growing at 87 degrees C. The archaeal ADP-ribosylation reaction was time-, temperature- and NAD-dependent. It proved to be highly thermostable, with about 30% decrease of 14C incorporation from [14C]NAD on incubation at 80 degrees C for up to 24 h. The main reaction product was found to be mono-ADP-ribose. Testing both [adenine-14C(U)]NAD and [adenine-14C(U)]ADPR as substrates, it was found that acceptor proteins were modified by ADP-ribose both enzymatically, via ADP-ribosylating enzymes, and via chemical attachment of free ADP-ribose, likely produced by NAD glycohydrolase activity. The synthesis of ADP-ribose-protein complexes was shown to involve mainly acceptors with molecular masses in the 40-100 kDa range, as determined by electrophoresis on polyacrylamide gel in the presence of sodium dodecyl sulphate.

Adenosine Diphosphate↗

PubMed1995

The use of a CT scan to predict the feasibility of decompression of the first segment of the facial nerve via the transattical approach.

Total surgical decompression of the facial nerve can be offered to patients severely affected by Bell's palsy whether via the transattical or middle fossa approach. We prefer, when feasible, the transattical approach because it does not violate the cranial vault. The purpose of this study was to find the anatomical parameter of the temporal bone, measured by means of computed tomography (CT scan) and to decide which of these approaches should be offered. Sixty temporal bones were studied by CT scan, and then dissected in order to perform total facial nerve decompression via the transattical approach. Correlation between the two studies was established. Results suggest that measurement by CT scan of the attical area in the axial plane (AAA) may determine those patients for whom the transattical approach to facial nerve decompression should be undertaken.

Facial Nerve↗

PubMed1995

[Multicenter study comparing the efficacy and tolerance of topical ciprofloxacin (0.3%) versus topical gentamicin (0.3%) in the treatment of simple, non-cholesteatomaous chronic otitis media in the suppurative phase].

A multicentre double-blind randomized study was carried out to compare topical ciprofloxacin and topical gentamicin in the treatment of simple non-cholesteatomatous purulent chronic otitis media. Three hundred and eight patients were included in the study, 159 treated with ciprofloxacin and 149 treated with gentamicin. The percentage of clinical success (elimination of otorrhoea) was 95% with ciprofloxacin and 94% with gentamicin (ns). Likewise, the percentage of bacteriological erradication was 96% with ciprofloxacin and 93% with gentamicin. Both drugs were well tolerated, without changes in the audiometric values. In these patients, topical ciprofloxacin shows the same efficacy as topical gentamicin without any potential ototoxic effect.

Administration, Topical↗

PubMed1995

Poly(ADP-ribosyl)ation of proteins associated with nuclear matrix in rat testis.

We have previously demonstrated that a significant percentage of poly(ADPR) polymerase is present, as a tightly-bound form, at the third level of chromatin organisation defined by chromosomal loops and nuclear matrix. The present work is focused on the study of poly(ADP-ribosyl)ation of proteins present in these nuclear subfractions. It has been shown that, due to the action of poly(ADPR) polymerase, the ADP-ribose moiety of [14C]NAD is transferred to both loosely-bound and tightly-bound chromosomal proteins, which in consequence are modified by chain polymers of ADP-ribose of different lengths. Moreover, histone-like proteins seem to be ADP-ribosylated in chromosomal loops and nuclear matrix associated regions of DNA loops (MARS). A hypothesis can be put forward that the ADP-ribosylation system is functionally related to the nuclear processes, actively coordinated by the nuclear matrix.

Animals↗