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Biomedical subjects

A Martini

Publications and source records attributed to A Martini.

At least 73 records · Page 4Linked to original sources
PubMed2000

Differential growth inhibition as a tool to increase the discriminating power of killer toxin sensitivity in fingerprinting of yeasts.

A panel of 27 cell-free crude killer toxin preparations were used in fingerprinting 45 Saccharomyces cerevisiae and 11 Saccharomyces exiguus strains. The differential sensitivity to different mycocins was evaluated both as binary data matrix (presence-absence of killing effect), and by considering the growth inhibition areas (measured by agar diffusion well bioassay). The first approach gave an individual fingerprinting of 68% of sensitive strains, whereas the second gave a total and reproducible (P<0.01) discrimination of all tested strains.

Antibiosis↗
PubMed2000

Langerhans' cell histiocytosis: report of a case with temporal localization.

The authors report a case of Langerhans' cell histiocytosis (LCH) with temporal localization and rapidly evolving initial clinical presentation in a 12-year-old boy. This disease of currently unknown etiology is actually considered a proliferative entity of cells with phenotypic characteristics of normal Langerhans' cells. An immunoregulation defect leading to abnormal maturation and migration of Langerhans' cells might be the basis for LCH. According to the Hystiocyte Society diagnostic criteria, ATPase, S 100 and D-mannoxidase positivity in addition to typical hystopathologic findings are sufficient for diagnosis of LCH. Head and neck localization of LCH occurs in about 70% of cases; males are more frequently affected than females, age at presentation varies from a few months to 15 years. Presenting features, initial diagnostic evaluation, differential diagnosis and treatment protocol of a unifocal monosystemic temporal bone localization of LCH are presented.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

Quantitative and qualitative analysis of the effectiveness of a mechanical method for the isolation of preantral follicles from ovine ovaries.

The preantral follicles are the major source of oocytes and its utilization has been investigated as an important tool to store large numbers of female gametes for further utilization in reproductive programs. The aim of the present study was to perform quantitative and qualitative analyses of the efficacy of a mechanical method for isolating of preantral follicles from the ovaries of fetuses and from nonpregnant and pregnant ewes, using as reference the population of preantral follicles in situ. In the isolation method the ovaries were cut into fragments in the tissue chopper. Then, the suspension was filtered through nylon mesh filters. The number of isolated follicles per ovary was 1655, 4735 and 4770, respectively, for the fetus, nonpregnant ewe and pregnant ewe. The number of in situ preantral follicles per ovary was 32961, 16627 and 17794, respectively, for the fetus, nonpregnant ewe and pregnant ewe. The follicle recovery rate (number of isolated preantral follicles/number of in situ preantral follicles x 100) was higher in adult ewes (26 and 28%, respectively, for nonpregnant and pregnant ewes) than in fetuses (5%). Histological analysis showed that very few preantral follicles (less than 0.26% in situ and 0.46% after the isolation procedure) were degenerated. In conclusion, this study showed that a mechanical method could be used effectively to isolate a large number of intact ovine preantral follicles. In the future, with improvements in culture systems, the isolation of a great number of oocytes enclosed in preantral follicles will make a valuable contribution to the rare breeds and endangered species, agricultural efficiency and basic research in folliculogenesis.

Animals↗
PubMed2000

Genomic structure and identification of novel mutations in usherin, the gene responsible for Usher syndrome type IIa.

Usher syndrome type IIa (USHIIa) is an autosomal recessive disorder characterized by moderate to severe sensorineural hearing loss and progressive retinitis pigmentosa. This disorder maps to human chromosome 1q41. Recently, mutations in USHIIa patients were identified in a novel gene isolated from this chromosomal region. The USH2A gene encodes a protein with a predicted molecular weight of 171.5 kD and possesses laminin epidermal growth factor as well as fibronectin type III domains. These domains are observed in other protein components of the basal lamina and extracellular matrixes; they may also be observed in cell-adhesion molecules. The intron/exon organization of the gene whose protein we name "Usherin" was determined by direct sequencing of PCR products and cloned genomic DNA with cDNA-specific primers. The gene is encoded by 21 exons and spans a minimum of 105 kb. A mutation search of 57 independent USHIIa probands was performed with a combination of direct sequencing and heteroduplex analysis of PCR-amplified exons. Fifteen new mutations were found. Of 114 independent USH2A alleles, 58 harbored probable pathologic mutations. Ten cases of USHIIa were true homozygotes and 10 were compound heterozygotes; 18 heterozygotes with only one identifiable mutation were observed. Sixty-five percent (38/58) of cases had at least one mutation, and 51% (58/114) of the total number of possible mutations were identified. The allele 2299delG (previously reported as 2314delG) was the most frequent mutant allele observed (16%; 31/192). Three new missense mutations (C319Y, N346H, and C419F) were discovered; all were restricted to the previously unreported laminin domain VI region of Usherin. The possible significance of this domain, known to be necessary for laminin network assembly, is discussed in the context of domain VI mutations from other proteins.

Amino Acid Sequence↗
PubMed2000

Nephrotic-range proteinuria, the major risk factor for early atherosclerosis in juvenile-onset systemic lupus erythematosus.

OBJECTIVE: To determine the presence of early carotid atherosclerosis and associated risk factors in patients with juvenile-onset systemic lupus erythematosus (SLE). METHODS: The carotid intima-media wall thickness (IMT) was measured by B-mode ultrasound in patients with SLE onset before the age of 16 years and in sex- and age-matched healthy control subjects. Risk factors for atherosclerosis were determined at the time of the ultrasound scan and included traditional cardiovascular and SLE-related risk factors. RESULTS: Twenty-six patients with juvenile-onset SLE and 26 healthy controls were studied. The mean (+/- SD) IMT of the SLE patients was significantly higher than that of the control group (0.57+/-0.05 mm and 0.54+/-0.03 mm, respectively; P = 0.006). The results of IMT measurement were not correlated with the patients' age, disease duration, SLE Disease Activity Index (SLEDAI) score, Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) Damage Index (DI) score, laboratory indicators of lupus activity, or cumulative prednisone dose. Patients with nephrotic-range (NR) proteinuria (> or = 3.5 gm/24 hours; n = 6) had a significantly higher IMT than did those without (n = 20) (P = 0.02). Patients with NR proteinuria also had significantly higher SLEDAI scores, SLICC/ACR DI scores, and systolic and diastolic blood pressures, and significantly higher levels of total cholesterol, low-density lipoprotein cholesterol, apolipoprotein B, and fibrinogen. No difference in any of the above variables, including the IMT, was observed when SLE patients without NR proteinuria were compared with healthy controls. CONCLUSION: These patients with juvenile-onset SLE had ultrasonographic evidence of premature atherosclerosis. The risk of early atherosclerosis may be higher in patients with NR proteinuria.

Adolescent↗
PubMed2000

Utilisation of differential killer toxin sensitivity patterns for fingerprinting and clustering yeast strains belonging to different genera.

The differential killer sensitivity of 103 yeast cultures belonging to 12 species (genera Debaryomyces, Kluyveromyces, Saccharomyces, and Zygosaccharomyces), all previously taxonomically certified by nDNA-nDNA reassociation, against a given panel of 39 killer yeasts was used as a fingerprinting tool. All strains, with the only exception of eight cultures belonging to the species Zygosaccharomyces bailii, were characterised by a specific, individual sensitivity pattern (killer formula). Cluster analysis of binary sequences based on killer sensitivity of strains belonging to different genera is presented and discussed.

Cluster Analysis↗
PubMed2000

Transient autonomic nervous system dysfunction during hyperacute stroke.

Forty-four patients suffering a stroke for the first time were examined within 10 h of the onset of symptoms; the tests performed on their admission to hospital, and thereafter on the third and seventh day, were 24-h Holter EKG with spectral analysis of heart rate variability, evaluation of arterial blood pressure and the levels of catecholamine in the blood and 24-h urine. The dynamic EKG on admission revealed that 31 (70.5%) out of the 44 patients already had arrhythmia. These alterations were observed in 9 (75%) out of 12 haemorrhagic patients with a significant (P < 0.05) prevalence compared to 22 (68.8%) of the 32 ischaemic ones. Arrhythmia showed up in 16 (76.2%) out of 21 cases with right hemisphere lesions and in 12 (63.2%) out of 19 cases of left hemisphere lesions; this difference was also significant (P<0.05). Arrhythmia was still present in 19 (43.2%) patients after 3 days and only in 2 (6.5%) patients after 7 days. The spectral analysis parameters on admission and after 3 days were significantly (P < 0.05) modified in patients with stroke plus arrhythmia, compared to patients with stroke alone and to control subjects, whereas no further differences were observed on the seventh day. Moreover, the percentage of patients with arterial hypertension and high levels of catecholamine greatly decreased from the third day onwards. A transient autonomic nervous system imbalance with prevalent sympathetic activity may justify this cardiovascular impairment during the hyperacute phase of stroke.

Acute Disease↗
PubMed2000

Efficacy of homeopathic treatment of skin reactions during radiotherapy for breast cancer: a randomised, double-blind clinical trial.

The aim of this study was to assess the effects of Belladonna 7cH and X-ray 15cH associated in the treatment of acute radiodermatitis. A randomized double-blind placebo-controlled clinical trial involving 66 patients who had been operated on for breast cancer and were undergoing radiotherapy was conducted. The following parameters were assessed over ten weeks: breast skin colour, warmth, swelling and pigmentation. The efficacy of the treatment was assessed by the comparison of these parameters taken individually and by calculating an Index of Total Severity (sum of the scores of the four parameters) during radiotherapy, and during recovery, 15 and 30 d after the end of the radiotherapy. The differences of the scores of the Index of Total Severity during Radiotherapy were not statistically significant, but showed a trend towards a better activity of the homoeopathic medicine compared to placebo. Analysis of the data on Total Severity during recovery, showed a statistically significant benefit of the active medicines over placebo. The homeopathic medicines had particular effectiveness on the heat of the skin. The limited number of patients observed and the posology employed could have interfered with the significance of the results. Chemotherapy and hormonotherapy do not seem to affect the results.

Adult↗
PubMed2000

Optimization of TEOAE recording protocols: a linear protocol derived from parameters of a time-frequency analysis: a pilot study on neonatal subjects.

Linear and non-linear TEOAE protocols were compared in terms of nine parameters in order to define the protocol producing recordings with the highest signal quality (lowest noise and highest signal-to-noise ratio). The pilot project acquired data using ILO-92 apparatus from 220 neonates (397 ears) at the second/third day after birth in three European laboratories. A Gabor spectrogram time-frequency representation of the recordings showed considerable frequency dispersion in TEOAE latencies >4.0 ms. The data, analysed with a Wilcoxon test, indicated that a linear TEOAE protocol: (i) generates recordings of a lower noise and a higher signal-to-noise (S/N) ratio in the 2.0, 3.0, 4.0 kHz TEOAE bands; (ii) the increase in the S/N ratio can result in a decrement of the required number of TEOAE sweeps; (iii) the higher values of S/N can be used in the estimation of more robust pass-fail criteria, minimizing the percentage of false positives and negatives.

Acoustic Stimulation↗
PubMed2000

Non-radioactive dot-blot DNA reassociation for unequivocal yeast identification.

Unequivocal and rapid classification of yeast cultures cannot be accomplished exclusively on the basis of unstable phenotypic traits, but requires molecular tests relating to the whole genome (or the largest possible portion of it). DNA-DNA reassociation meets this requirement, although many procedures proposed for calculating overall sequence similarity are expensive and time-consuming, thus restricting the possibility of unequivocal classification to a few specialized laboratories. A novel method, based on non-radioactive dot-blot hybridization of whole genomic DNA, has shown high and reproducible proportionality between the detected signal and the amount of double-stranded DNA effectively present on the membrane. This procedure has been optimized to obtain, within two working days, DNA relatedness values between unknown cultures and the type strains of the species previously indicated by a few conventional tests. The effective ability of the method to discriminate strains belonging to different species has been tested within taxonomic models consisting of yeast type cultures already certified by spectrophotometric reassociation.

DNA, Fungal↗
PubMed2000

Biodiversity of killer activity in yeasts isolated from the Brazilian rain forest.

The occurrence of killer activity against a panel composed of 22 industrially and (or) medically important yeasts was investigated in 438 yeast and yeast-like cultures belonging to 96 species, isolated from different environments of the Brazilian rain forest. Altogether, 26% of ascomycetes, 56% of basidiomycetes, and 42% of yeast-like cultures exhibited killer activity against at least one of the panel yeasts. More than 15 species never reported before as toxin producers were found, with Pseudozyma antarctica, Trichosporon asteroides, and Geotrichum klebahnii, showing the broader activity spectra. Plasmid curing did not cure the killer phenotypes of Candida maltosa, Debaryomyces hansenii, G. klebahnii, Tr. asteroides, Cryptococcus laurentii, and Ps. antarctica.

Ascomycota↗
PubMed2000

Use of a hyaluronan-based biomembrane in the treatment of chronic cholesteatomatous otitis media.

OBJECTIVE: To test the efficacy and safety of a hyaluronan-based biomembrane in stimulating the healing process in patients undergoing tympanomastoid surgery. STUDY DESIGN: The trial was an open, two-arm, controlled, randomized, prospective, multicenter study conducted at two different hospitals. PATIENTS: Sixty subjects (18-65 years of age, both sexes) with chronic cholesteatomatous otitis media were enrolled and treated by the "one-stage open technique." Efficacy and safety parameters were assessed at 3, 5, 7, 9, 11, 13, 17, 21, and 25 weeks after surgery. Three sets of composite criteria were considered: patient's assessment of quality of healing, otomicroscopy, and audiometry. RESULTS: Of the 60 patients, 50 completed the study. Subjects treated with the biomembrane had statistically significant better scores than controls (no treatment) for all variables considered, excluding audiometry (no significant differences). No adverse events occurred in treated patients. CONCLUSION: Data demonstrate that the application of a hyaluronan-based biomembrane improves the healing of the mastoid cavity following "open" tympanoplasty. In particular, re-epithelialization was significantly faster after the application of the biomembrane. Moreover, the device neither caused any adverse events nor showed signs of ototoxicity. Re-epithelialization of open cavities and tympanic grafts still represents for surgeons an unpredictable step in the healing process. Hyaluronian-derivates may effectively contribute to the reduction of such variability.

Adjuvants, Immunologic↗
PubMed2000

Circulating levels of soluble E-selectin, P-selectin and intercellular adhesion molecule-1 in patients with juvenile idiopathic arthritis.

OBJECTIVE: To measure circulating levels of soluble E-selectin (sE-selectin), sP-selectin, and soluble intercellular adhesion molecule-1 (sICAM-1) in patients with active juvenile idiopathic arthritides (JIA), and to evaluate their correlation with disease activity variables and cytokine levels. METHODS: Serum levels of sE-selectin, sP-selectin, and sICAM-1 were measured by ELISA in 42 patients with JIA and in 15 healthy controls. RESULTS: Circulating levels of sE-selectin and sICAM-1, but not sP-selectin, were significantly elevated in patients with active systemic JIA. In patients with active polyarticular or pauciarticular JIA serum levels of sE-selectin. sP-selectin, and sICAM-1 were comparable to those of controls. In patients with systemic JIA, levels of sE-selectin and sICAM-1 were significantly correlated with levels of soluble tumor necrosis factor receptor 2 (sTNFR2), but not with those of interleukin 6 (IL-6) or IL-1beta. CONCLUSION: Patients with active systemic JIA have elevated circulating levels of sE-selectin and sICAM-1. The correlation with sTNFR2, together with previous data on the TNF system in systemic JIA. suggests that TNF activated endothelial cells are the source of sE-selectin and sICAM-1 in this disease.

Adolescent↗
PubMed2000

Latex allergy. History, diagnosis and prevention.

During the past 10 years the incidence of natural rubber latex (NRL) allergy has dramatically increased. It occurs predominantly in certain high risk group: health care workers, latex industry workers, immune compromised individuals (such as children with spina bifida) and persons with positive risk factors (such as multiple surgeries). The epidemiology, history, mechanism, clinical symptoms and signs, and diagnosis of latex allergy are presented briefly. The subject of this review is to understand the importance in reducing the prevalence of latex allergy: reducing exposure, using appropriate work practices, training and educating workers, monitoring symptoms and substituting non latex products when appropriate.

Adult↗
PubMed2000

[Distortion product otoacoustic emission (DPOAEs) and newborn hearing screening: a feasibility and performance study].

In view of the great psychological effect deafness has on one's social life, the scientific community has long sought the best way to define the hearing function. The development of new technologies in this field has set "early intervention" as the primary target for screening. For this reason, within the contest of a program of audiological newborn hearing screening, the Authors have used data from a selected group of 1250 newborns to (a) compare the clinical feasibility and performance of three different DPOAE protocols and (b) establish the scoring criteria defining "pass" or "fail" responses. All subjects participating in this study were randomly selected and their normal hearing was verified by linear TEOAE recordings. The test was carried out, using an Otodynamics ILO92 Analyser version 5.60, on the second day of life or later (in case of extended recovery), during natural sleep and after feeding. The DPOAE recordings were elicited using asymmetric stimuli with L1 > L2 and a frequency-ratio of 1.22 following three different SPL protocols: 60-50 dB (PR1), 65-55 dB (PR2) and 75-65 dB (PR3). Five frequencies of the cubic distortion product (referring to f2) were tested with an ILO macro at 1.5 KHz, 2.0 KHz, 3.0 KHz, 4.0 KHz and 5.0 KHz. The statistical evaluation of differences in the signal-to-noise ratio (S/N) between the PR1 and PR2 protocols showed no significant differences. On the other hand significant differences were found between the PR3 and the PR2 S/N ratios, the former providing the best performance (higher values). The scoring criteria were defined by minimum free distribution tolerance intervals of the S/N ratios at the five tested frequencies. In conclusion this study confirms the feasibility of DPOAE recordings in a un iversal newborn hearing screening program and shows the appropriate pass-fail parameters to be used for this purpose. It should be noted that this approach enables acquisition of frequency-specific information which might further improve audiological diagnosis.

Cochlea↗