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PubMed2001

Microalbuminuria, pulse pressure, left ventricular hypertrophy, and myocardial ultrasonic tissue characterization in essential hypertension.

Microalbuminuria (UAE) may be considered a marker of systemic vascular dysfunction, while pulse pressure (PP) is an indicator of the stiffness of vascular conduits. Both these parameters, together with left ventricular hypertrophy (LVH), are linked to cardiovascular morbidity in hypertensive patients. The aim of this study was the analysis of the possible relationships among UAE, PP, and LVH with ultrasonic myocardial textural parameters, which are altered in hypertensives patients. A group of male (n = 70) essential hypertensive patients (mean age: 58 +/- 7 yr) was analyzed with a group of age-comparable normotensive healthy subjects as controls (n = 32). Ambulatory blood pressure monitoring (ABPM) was performed with an oscillometric monitor; UAE was measured by nephelometry. A conventional 2D-Doppler echocardiography (to analyze left ventricular mass: LVM) and a quantitative analysis of the echocardiographic digitized imaging with the use of a calibrated digitization system (to calculate the septum and the posterior wall textural parameters) were performed on all subjects. The myocardial mean gray level was calculated to derive the cyclic variation index (CVI). The CVI was significantly lower in hypertensives both for the septum (- 16.3 +/- 22.8 vs 34.7 +/- 15.3%; p < 0.001) and for the posterior wall (- 15.2 +/- 23.6 vs 38.2 +/- 15.4%; p < 0.001). A significant negative correlation was found between logUAE and the CVI of the septum (r = -0.42; p < 0.001), between the PP and the CVI of the septum (r = -0.40; p < 0.002) and between the CVI and the LVM (r = -0.38; p < 0.001). Multiple regression analysis having as dependent variable the CVI at septum level showed as significantly related independent variables: PP (p < 0.01), logUAE (p < 0.001), and LVM (p < 0.05) (multiple R: 0.76, squared multiple R: 0.57; p < 0.001). It was found that LVM, logUAE, and PP are all correlated with textural parameters, and the CVI can be considered a sensitive parameter in the identification of an abnormal myocardial texture in hypertension. A high level of arterial stiffness and the presence of vascular dysfunction in essential hypertension could participate in the determination of myocardial alterations and permit the identification of patients with the worst prognosis in terms of morbidity or mortality due to cardiovascular events.

Albuminuria↗

PubMed2002

Electrically stimulated glottal opening combined with adductor muscle botox blockade restores both ventilation and voice in a patient with bilateral laryngeal paralysis.

The purpose of this study was to determine whether paced electrical stimulation of the posterior cricoarytenoid muscle with an implantable device could restore ventilation in a patient with bilateral vocal fold paralysis without disturbing voice. In the first US case of a multi-institutional study, this patient was implanted with an Itrel II stimulator (Medtronic, Inc). In monthly postoperative sessions over an 18-month period, an effective stimulus paradigm was derived, the magnitude of stimulated vocal fold abduction and ventilation was measured, and perceptual judgments of voice quality were made. After identification of optimum parameters, posterior cricoarytenoid muscle stimulation produced a moderately large vocal fold abduction of 4 mm, but only marginal improvement in mouth ventilation, with no change in voice quality. After adductor muscle blockade with botulinum toxin, the patient's voice improved with increased phonatory airflow, but ventilation through the passive airway was still inadequate. However, by combining these two therapeutic strategies, dynamic abduction increased to 7 mm, ventilation through the mouth surpassed that through the tracheotomy (allowing decannulation), and voice quality was restored to normal.

Botulinum Toxins, Type A↗

PubMed2006

Systematic interpretation of microarray data using experiment annotations.

BACKGROUND: Up to now, microarray data are mostly assessed in context with only one or few parameters characterizing the experimental conditions under study. More explicit experiment annotations, however, are highly useful for interpreting microarray data, when available in a statistically accessible format. RESULTS: We provide means to preprocess these additional data, and to extract relevant traits corresponding to the transcription patterns under study. We found correspondence analysis particularly well-suited for mapping such extracted traits. It visualizes associations both among and between the traits, the hereby annotated experiments, and the genes, revealing how they are all interrelated. Here, we apply our methods to the systematic interpretation of radioactive (single channel) and two-channel data, stemming from model organisms such as yeast and drosophila up to complex human cancer samples. Inclusion of technical parameters allows for identification of artifacts and flaws in experimental design. CONCLUSION: Biological and clinical traits can act as landmarks in transcription space, systematically mapping the variance of large datasets from the predominant changes down toward intricate details.

Cluster Analysis↗

PubMed2004

Evolutionary fuzzy modeling human diagnostic decisions.

Fuzzy CoCo is a methodology, combining fuzzy logic and evolutionary computation, for constructing systems able to accurately predict the outcome of a human decision-making process, while providing an understandable explanation of the underlying reasoning. Fuzzy logic provides a formal framework for constructing systems exhibiting both good numeric performance (accuracy) and linguistic representation (interpretability). However, fuzzy modeling--meaning the construction of fuzzy systems--is an arduous task, demanding the identification of many parameters. To solve it, we use evolutionary computation techniques (specifically cooperative coevolution), which are widely used to search for adequate solutions in complex spaces. We have successfully applied the algorithm to model the decision processes involved in two breast cancer diagnostic problems, the WBCD problem and the Catalonia mammography interpretation problem, obtaining systems both of high performance and high interpretability. For the Catalonia problem, an evolved system was embedded within a Web-based tool-called COBRA-for aiding radiologists in mammography interpretation.

Breast Neoplasms↗

PubMed2005

Comparison between gamma and beta irradiation effects on hydroxypropylmethylcellulose and gelatin hard capsules.

The effects of electron beam or gamma-irradiation on technological performances (capsule hardness, expressed as deforming work and dissolution time) of empty 2-shell capsules made of gelatin or hydroxypropylmethylcellulose (HPMC) were studied. Capsule structural changes induced by radiation treatment were investigated by capillary viscometry and atomic force microscopy (AFM). The capsules were irradiated in the air at 5, 15, and 25 kGy. The deforming work of nonirradiated HPMC capsules (0.06 +/- 0.01 J) was lower than that of gelatin capsules (0.10 +/- 0.01 J). The dissolution time of the HPMC capsules (414 +/- 33 seconds) was slightly higher than that determined for gelatin hard capsules (288 +/- 19 seconds). The hardness and dissolution time of gelatin and HPMC capsules were not significantly influenced by the irradiation type and the applied irradiation dose. As the viscometry analyses are concerned, irradiation caused a reduction of the intrinsic viscosity and water and dimethyl sulfoxide solvent power in both the cases. AFM analysis showed that the radiation treatment did not appreciably affect the surface roughness of the samples nor induce structural changes on capsule surface. However, measurements of force-distance curves pointed out a qualitative parameter for the identification of the irradiated capsules. On the bases of these preliminary results, empty gelatin or HPMC hard capsules can be sanitized/sterilized by ionizing radiation.

Beta Particles↗

PubMed2005

Quality assessment of radix salviae miltiorrhizae.

This paper describes an improved quality assessment method for Radix Salviae Miltiorrhizae (Root of Salvia miltiorrhiza BGE.) which was established using chromatographic fingerprinting and quantification of multiple marker compounds in the crude drug. High-performance thin-layer chromatography (HPTLC) fingerprinting of water-soluble phenolics and nonpolar tanshinones was performed separately and the authentication of Radix Salviae Miltiorrhizae was achieved by comparing the fingerprints of the samples with those of the reference crude drug and by comparing the Rf values of the bands in TLC fingerprints with those of reference compounds. HPLC fingerprints were obtained by simultaneous separation of phenolics and diterpenoids in Radix Salviae Miltiorrhizae. The HPLC fingerprints of seven batches of samples from different regions of China showed similar chromatographic patterns, and seven peaks were selected as characteristic peaks. The relative retention time of these characteristic peaks in the HPLC fingerprints was established as an important parameter for the identification of this herbal medicine. The pharmacologically active marker compounds salvianolic acid B, rosmarinic acid, and tanshinone IIA in herbal medicine were quantitatively determined using reverse-phase HPLC techniques. The HPLC quantitation methods of the three marker compounds were validated and the measurement uncertainty, which is important for setting the proposed content limit of the marker compounds in herbal medicine, were further evaluated.

Drug Evaluation, Preclinical↗

PubMed1995

Orbital osteology: a study of the surgical landmarks.

This study was conducted to re-examine the osteological anatomy of the orbit. Previous studies examined dried human skulls; this study looks at cadaveric specimens in a population that more closely resembles the population in the United States. Measurements were made of the bony orbit to define safe distances for surgical intervention and to identify distances to intraorbital fissures, canals, and foramina. Safe distances to the optic nerve were identified by subtracting 5 mm from the shortest measured specimen. The safe distances were as follows: medial quadrant, 29 mm; inferior quadrant, 39 mm; superior quadrant, 38 mm; and lateral quadrant, 36 mm. Staying close to the bony wall, not exceeding these parameters, and careful identification of anatomical structures should keep the surgeon from inadvertent damage to the intraorbital structures.

Cadaver↗

PubMed2005

Evaluation of the magnitude of the bronchodilator response in children and adolescents with asthma.

STUDY OBJECTIVE: Bronchodilator response criteria have been determined in adults; however, data applicable to children and adolescents are scarce. We measured pulmonary function in asthmatic patients to determine the bronchodilator response. DESIGN: A blind study. SETTING: Outpatient clinic of Pneumology Unit, Instituto da Crianca and Center of Asthma Care and Research, University Hospital, University of Sao Paulo Medical School. PATIENTS: Sixty patients aged 6 to 20 years (median, 12 years). INTERVENTIONS: Spirometry and plethysmography were performed before and after blind placebo and bronchodilator inhalation (400 mug salbutamol by metered-dose inhaler). MEASUREMENTS AND RESULTS: Approximately 90% of the patients had mild-to-moderate persistent asthma. The mean FEV(1) at baseline was 79.6% of the predicted value. Distribution of variations of the different pulmonary function parameters was analyzed after placebo inhalation. The 95th percentile was adopted as a criterion for a significant bronchodilator response. After the bronchodilator test, the patients were classified based on criteria derived from the placebo inhalation and the American Thoracic Society guidelines. Parameters established as cutoff values were 265 mL, 14.2% and 10% FEV(1) expressed as absolute volume, percentage compared with that at baseline and percentage of the predicted value, respectively, and 55% specific airway conductance (sGaw) expressed as a percentage compared with that at baseline. Based on the spirometric data, 37 patients (61%) had reversibility of obstruction, while 48 patients (80%) were classified as responders based on the analysis of variations in sGaw. The classifications based on variations in FEV(1) expressed as absolute volume and percentage of the predicted value showed a substantial correlation with the international classification. CONCLUSIONS: The cutoff values established for the assessment of the bronchodilator response in the present population agree with those reported in the literature. sGaw was the most sensitive parameter for the identification of changes in airway caliber.

Adolescent↗

PubMed2001

[Treatment with medicinal plants: a modality of child care by mothers and educating nurses].

Ten women living in the outskirts of Teresina were studied in order to find out which plants were used by them in the treatment of up to five-year-old children presenting respiratory problems. The creative and sensitive method proposed by Cabral was used to produce and analyze data. The study was supported by Freire's critical and reflective theory to reach the following generating themes: identification, indication and part of the plant used. The meeting of the women's common sense and scientific knowledge demonstrates that: the indication and the desired effect are the same whereas the part of the plant used and its identification follow different parameters. The fusion of both types of knowledge contributed to reveal the risk of toxicity due to indiscriminate use.

Adult↗

PubMed2000

New strategies in the treatment of acute myelogenous leukemia: mobilization and transplantation of autologous peripheral blood stem cells in adult patients.

During the last decade high-dose Ara-C (HIDAC; single doses of 3 g/m(2)) and autologous stem cell transplantation have been increasingly used as postremission therapy in adult acute myelogenous leukemia (AML). Controlled clinical trials have demonstrated a long-term disease-free survival of 40%-50% for patients treated with at least two courses of HIDAC. Other studies have demonstrated that postremission autologous bone marrow transplantation results in a disease-free survival equal to or better than conventional chemotherapy. However, autotransplantation with mobilized peripheral blood stem cells (PBSC) would now be preferred instead of autologous bone marrow, due to the shorter hematopoietic reconstitution period. The results reviewed in the present article suggest that HIDAC and autologous PBSC transplantation can be combined in the postremission treatment of adult AML, and this combination therapy may also reduce minimal residual disease and the risk of posttransplant relapse. From the available studies it cannot be concluded whether graft purging further reduces the relapse risk. However, the possible advantage of combination therapy with repeated courses of HIDAC and autologous PBSC transplantation needs to be demonstrated in prospective clinical trials before it can be recommended as a part of the routine treatment in AML.

Adult↗

PubMed2000

Parameter on mucogingival conditions. American Academy of Periodontology.

The American Academy of Periodontology has developed the following parameter on the identification and treatment of mucogingival conditions. Patients should be informed of the disease process, therapeutic alternatives, potential complications, expected results, and their responsibility in treatment. Consequences of no treatment should be explained. The consequences of this option may range from no change in the condition to progression of the defect. Given this information, patients should then be able to make informed decisions regarding their periodontal therapy.

Gingival Diseases↗

PubMed2003

Two-color image analysis discriminates between mineralized and unmineralized bone nodules in vitro.

Functional assays of progenitor cell capacity for colony formation in vitro typically depend on the investigator's expertise with quantification. The ability to enumerate and analyze colony types with standardized criteria with no bias would be a useful tool for research and drug development. We report the development of a two-color automated analysis system for colony-forming unit-osteoblasts that is capable of reporting progenitor frequency and bone nodule number size, and type (mineralized or unmineralized). Our image analysis system was validated using the rat calvaria cell model to measure in vitro bone nodule development. With computer-aided image analysis, data on nodules can be rapidly generated with a minimum of user bias and fatigue. This novel tool will distinguish mineralized and unmineralized bone nodules, facilitates quantification, enable large-scale experimental design, allow for long-term data storage and tracking, and lead to the identification of new parameters that impact bone development.

Animals↗

PubMed1999

[Weaning of immunosuppression in living-related liver transplantation].

In our experience of living donor liver transplantation (LDLT), some recipients could be successfully weaned from any immunosuppressant in case of various situations like severe infectious complications, posttransplant lymphoproliferative disorder, and noncompliance. Based on such unexpected experiences, we started the intentional weaning of immunosupressants after LDLT. The patients were selected among the recipients who had been followed up longer than two years with stable normal graft function, and without any rejection episodes in the latest one year. So far, 26 cases were enrolled into this program, and 6 cases could be intentionally weaned from any immunosuppressants. Four recipients unfortunately had a rejection episode during the weaning. Immunosuppressants were again returned to the pre-weaning level in these recipients, and the rejection could be treated without any persistent dysfunction of the graft. Clear discrimination of the recipients who will be or will not be able to be weaned from immunosuppression is still impossible. Mixed lymphocyte reaction showed tendency of low response to the donor, but the result is not stationary in all recipients. Identification of suitable parameters to promise the possibility of weaning is a big problem to be solved in the future.

Graft Rejection↗

PubMed2006

Neurosyphilis is unlikely in patients with late latent syphilis and a negative blood VDRL-test.

Patients with latent syphilis or syphilis of unknown duration should be evaluated for tertiary disease and neurosyphilis. The aim of this retrospective study was to determine relevant serological parameters for the identification of those individuals with syphilis who are most likely to have neurosyphilis and who therefore require lumbar puncture. After excluding repeated estimates and patients whose blood syphilis serology had either been negative or not been determined within 3 months of lumbar puncture, 265 out of 710 cerebrospinal fluids from 1988 to 2004 were analysed. In each of those patients the earliest available pairs of serum and cerebrospinal fluid samples were evaluated. The diagnosis of neurosyphilis was based on criteria according to established guidelines. Forty-three of 265 patients (16.2%; 5 women, 38 men; mean age 47+/-16 years) had neurosyphilis. Seven of 72 (9.7%) of those testing HIV-positive, fulfilled the criteria of neurosyphilis. Not a single patient with neurosyphilis tested Venereal Disease Research Laboratory test (VDRL)-negative in peripheral blood, an effect which was highly significant (p < 0.01, chi2-test). The median blood-VDRL titre was significantly higher in patients with neurosyphilis than in those without (1:32 vs. 1:0; p < 0.01, t-test, two-sided). Hence, neurosyphilis is very unlikely in patients with a negative blood-VDRL. Therefore, lumbar puncture is not recommended in these patients.

Adult↗

PubMed1995

Postural control and vestibulospinal function in patients selected for cochlear implantation.

Postural control, vestibular and eye motor function were evaluated in seven postlingually deaf patients before cochlear implantation and were compared with 21 control subjects. Vibration to the calf muscles or galvanic electrical stimulation of the vestibular nerves, perturbed stance and body sway velocity, statistical variance of antero-posterior body sway and identification of characteristic parameters of postural dynamics were all evaluated. Vibration-induced body sway was increased among the patients compared with the normal subjects and there were differences in characteristic parameters of postural dynamics, indicating decreased postural control. Galvanic stimulation induced a body sway not significantly different from the control group suggesting that the patients selected for cochlear implantation, and with an otherwise reduced postural control, are sensitive to electrical stimulation of the vestibular nerve. Thus, postlingually deaf subjects who perceive a sensation of sound at electrical promontorial stimulation also respond with increased body sway to electrical stimulation aimed at the vestibular nerves. This finding may contribute an additional hypothesis to the causes of dizziness among cochlear implant patients, complementary to the that of wrongly placed electrodes and peroperative vestibular lesions.

Adult↗

PubMedDate not supplied

The palpator: an instrument for measuring the positions of bones in three dimensions.

In order to measure the three-dimensional (3D) position of the shoulder girdle bones, as well as the 3D positions of muscle attachments and joint surfaces in cadaver experiments, a measurement instrument, called the palpator, was developed. The palpator is composed of an open chain of four links connected by four hinges. By recording the rotation of the hinges using potentiometers, the position of the end-point of the palpator can be calculated. After the identification of 23 parameters of the palpator, a measurement accuracy of 1.43 mm is obtained.

Biomechanical Phenomena↗

PubMedDate not supplied

Solitary nonparasitic cysts of the liver: the Boston Children's Hospital experience.

A 3 3/12-year-old female child with abdominal distention, new onset pain, and tenderness is described. The child underwent surgical resection of a multilocular cyst of the right lobe of the liver. We reviewed the autopsy and surgical files of Children's Hospital for the past 63 years to identify other congenital cysts of the liver. We found 30 additional cases including 4 multilocular cysts. The origin of these cysts, a review of the literature, and a discussion of diagnostic parameters for the identification of such cysts in context with other hepatobiliary cystic lesions are presented.

Child↗

PubMed1987

Transvascular exchange of fluid and plasma proteins.

A theoretical model of transvascular exchange of fluid and plasma proteins in the microcirculation is developed based on fundamental laws of the fluid mechanics and on phenomenological transport equations of the irreversible thermodynamics. Intravascular axial changes of the pressure, flow and plasma protein concentration are taken into account as well as axial gradients of vascular permeability. Proper nondimensionalization of the resulting equations leads to the identification of dimensionless parameters which combine the transport characteristics of the endothelial wall and the intravascular flow resistance. In the theory, the dependence of the reflection coefficient on the transport coefficients of the vascular wall and on the plasma protein concentration is established. The model is applied to the cat mesentery and the rat intestinal muscle. The numerical simulations indicate that taking into account vascular protein permeability yields considerable differences in the axial distribution of the plasma protein concentration and transvascular fluxes in comparison with the case of protein impermeability of the endothelial wall. The results show that the maximum of the transvascular fluid and plasma protein movement resides at the site of the small venules while a minimum of the exchange occurs at the site of the midcapillaries.

Animals↗