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PubMed2004

The effect of washing water on bonding to etched enamel.

There is current concern about bacterial contamination of dental unit waterlines. This research hypothesized that the presence of increasing concentrations of bacteria in water used to wash etched enamel would result in a corresponding decrease in both shear bond strength (SBS) and critical surface tension (gammaC) of enamel. A further hypothesis was made that there is a correlation between SBS and gammaC. The effect of 3.5 ppm iodine in the water as a bacteriostatic agent was also assessed. Five groups of 10 samples of bovine enamel were etched, washed, and a resin composite bonded to them. The control group was washed with distilled water. Another group was washed with the dilute iodine solution. The remaining three groups used a different concentration of Escherichia coli DH5alpha as follows (in cfu mL(-1)): group 1: 10(2); group 2: 10(4); group 3: 10(6). Shear bond strength data were measured on an Instron testing machine at a crosshead speed of 1 mm min(-1). Adhesion data were (MPa): control: 24.6 +/- 6.0; with iodine: 20.8 +/- 2.7; group 1: 19.8 +/- 2.7; group 2: 13.5 +/- 3.0; group 3: 13.9 +/- 3.6. The F-test yielded a highly significant difference between control group, iodine group and group 1, compared with groups 2 and 3 (P < 0.0001). Tukey's Studentized Range Test was used for pairwise comparison testing between groups. Using a Cahn dynamic contact angle analyzer and linear regression analysis, the plots of surface tension versus costheta were extrapolated to costheta = 1 to give gammaC data for the control group and groups 1-3. In all cases reasonable linearity was observed (r2 > or = 0.87). Data (mN m(-1)) were: control group: 50.8; group 1: 45.1; group 2: 43.2; group 3: 39.5. The SBS and gammaC were then plotted against each other and linear regression analysis performed. It was concluded that increasing concentrations of bacteria in wash water decreased both SBS and gammaC and that a linear correlation (R2 = 0.84) was found between the values of these two parameters.

Acid Etching, Dental↗
PubMed1993

A mathematical model for cell killing by heat applied to a C3H mammary carcinoma in vivo.

Jung (1986) has proposed a mathematical model for cell killing by hyperthermia which assumes that heat killing involves two steps: the production (p) of non-lethal lesions at random and a subsequent conversion (c) into lethal lesions. The p & c model has been shown to predict the survival of CHO cells heated in vitro even when complicated biological phenomena such as thermotolerance and step-down heating (SDH) are involved (Jung 1986, 1991). In the present study the objective was to test the p & c model's ability to describe the effect of single heating and SDH in an experimental tumour in vivo. The endpoint was tumour growth delay (GD). The doubling times (DT) for untreated and heated tumours were similar, and the surviving fraction (SF) could therefore be estimated using: SF = -in(2).GD/DT. SF was fitted to the model by non-linear regression. The p & c model adequately described the GD obtained by SDH (39-44.5 degrees C) and single heating above 42.5 degrees C. Multiple linear regression showed that the residuals for single heating and SDH were independent of both heating time and temperature. However, the residuals for single heating (41-44.5 degrees C) were significantly correlated to heating time when analysed separately. The GD obtained by the use of extended single heating times at or below 42.5 degrees C was therefore overestimated by the model. Development of chronic thermotolerance during heating may account for the observed divergence. The Arrhenius plots for both p and c were log-linear with activation energies of 678 and 311 kJ/mol, respectively. Jung (1986) has previously reported similar p and c activation energies above 42.5 degrees C for CHO cells in vitro.

Animals↗
PubMed2005

Elevated C-reactive protein augments increased arterial stiffness in subjects with the metabolic syndrome.

We examined whether the presence of an increasing number of metabolic syndrome "disorders" was associated with an increasing pulse wave velocity, which is recognized as a marker of cardiovascular risk, and evaluated whether an elevated plasma C-reactive protein level augments this increasing pulse wave velocity. Using a cross-sectional study design, C-reactive protein, metabolic syndrome-related anthropometric parameters, and pulse wave velocity were measured in 5752 middle-aged Japanese men (44+/-10 years old). In linear regression analyses, all of the metabolic "disorders" and the logarithm of the C-reactive protein significantly correlated with pulse wave velocity. Multiple linear regression analysis demonstrated that triglycerides, HDL cholesterol, mean blood pressure, fasting glucose, and the logarithm of the C-reactive protein were significant independent positive predictors of pulse wave velocity (R-square=0.38). The presence of an increasing number of metabolic "disorders" in the subjects was associated with an increasing pulse wave velocity (no disorders 1228+/-139 cm/s > or =3 disorders 1437+/-250 cm/s; P<0.01). Among subjects with the metabolic syndrome, pulse wave velocity was higher in cases with (1508+/-278 cm/s) than in those without an elevated C-reactive protein (1427+/-243 cm/s; P<0.01). In conclusion, an increase in arterial stiffness may constitute a pathophysiological basis for the increased risk of cardiovascular disease in patients with the metabolic syndrome and that an elevated C-reactive protein level may aggravate this cardiovascular risk.

Adult↗
PubMed1998

A submaximal all-extremity exercise test to predict maximal oxygen consumption.

PURPOSE: Submaximal aerobic exercise testing is utilized with a variety of populations to assess fitness level and predict maximal oxygen uptake (VO2peak) when a maximal test is not possible or preferable. Many submaximal tests have been developed on traditional exercise equipment, such as the treadmill and the cycle ergometer, but are not available for newer equipment such as an all-extremity ergometer. The purpose of this study was to develop and validate a submaximal exercise test using the Pro II Power Trainer, an all-extremity ergometer, in women ages 30-60 without disability and with varying fitness levels. A secondary purpose was to compare VO2peak values achieved during the all-extremity maximal test and the treadmill test. METHODS AND RESULTS: A linear regression equation was developed to predict VO2peak from submaximal data using heart rates and power output at the sixth and ninth minutes of the submaximal test. The linear regression derived for the submaximal all-extremity test was VO2peak L.min-1 = -0.01 (age in years) - 0.0029 (HR 1) - 0.0099 (HR2) - 0.0029 (PO1) + 0.0151(PO2) + 3.010. Predicted residual sum of squares of the linear equation revealed an R2 value of 0.722 and standard error of estimate of 0.216 L.min-1. Treadmill VO2 speak values correlated strongly with all-extremity VO2 speak values (r = 0.918) and were not significantly different (P, 0.05). CONCLUSION: A similar submaximal test needs to be developed for field estimates of VO2peak for subpopulations of individuals with physical disabilities such as rheumatoid arthritis, head or spinal cord injury, cerebral vascular accident, multiple sclerosis, amputation, and cerebral palsy.

Adult↗
PubMed1999

Cigarette smoking, alcohol use, and physical activity in relation to serum leptin levels in a multiethnic population: The Miami Community Health Study.

PURPOSE: To examine the correlates of plasma leptin, including fasting insulin, adiposity, and several health habits and behaviors among a nondiabetic multiethnic population. METHODS: A cross-sectional study was conducted among 25-44 year old African-Americans (n = 126), Cuban-Americans (n = 107), and non-Hispanic whites (n = 189) randomly selected from Dade County Florida. Fasting leptin levels were correlated with fasting insulin, percent body fat, smoking, alcohol use, and physical activity within each sex. Multiple linear regression and analysis of covariance were used to estimate the independent determinants of plasma leptin concentration separately among men and women. RESULTS: Stepwise linear regression analyses revealed statistically significant associations of leptin with percent body fat, fasting insulin, cigarette smoking, and physical activity (both inversely) among men (p < 0.05 for each). Among women, percent body fat, fasting insulin (both positively), cigarette smoking, and alcohol use (inversely) were independent predictors of leptin levels explaining over 70% of the variance. Analyses of covariance revealed that women had higher adjusted mean leptin levels than men (13.1 ng/ml vs. 5.9 ng/ml; p < 0.001), whereas no separate effect of ethnicity was noted. CONCLUSIONS: Although adiposity was the strongest correlate of leptin levels, fasting insulin and several health habits and behaviors were independently associated with leptin. After adjustment for these factors, women had significantly higher mean leptin levels than men. The independent association among leptin and insulin levels is intriguing and suggests additional avenues for epidemiologic research.

Adult↗
PubMed2003

Para-aminobenzoic acid (PABA) used as a marker for completeness of 24 hour urine: effects of age and dosage scheduling.

OBJECTIVE: To examine the age dependency of the urinary para-aminobenzoic acid (PABA) excretion, and if a delayed PABA excretion can be overcome by advancing intake schedule; and to examine the recovery of PABA in fractionated urinary samples collected during 24 h after single and repeated doses of PABA. DESIGN: Cross-over study with subjects randomized to start with recommended schedule of PABA administration (80 mg at 08:00, 12:00 and 18:00; PABA18) and then an advanced schedule (80 mg at 08:00, 12:00 and 15:00; PABA15) or vice versa. One subgroup of eight subjects collected individual urine specimens for 24 h after a morning dose of 80 mg of PABA, and another subgroup of 10 subjects collected individual urine specimens for 24 h after ingestion of 80 mg of PABA three times at mealtimes. SUBJECTS: Employees and relatives from the Danish Food Administration. SETTING: Ninety-nine healthy volunteers (61 females and 38 males) aged 30-91 y. RESULTS: Linear regressions for PABA15 and PABA18 demonstrate significantly less recovery with age (PABA15: r(2)=0.1784, P=0.0002; PABA18: r(2)=0.1273, P=0.0019). Linear regression of DeltaPABA (PABA15-PABA18) with age showed the best fit line to be horizontal (slope -0.0066, P=0.89; 95% CI -0.1046, 0.0915) and with a Y-intercept not significantly different from 0 (1.575; 95% CI -4.176, 7.326). In this population the lower limit for complete 24 h urine collection was 79.2%. After a single dosage of 80 mg PABA 70-85% was recovered after 8 h. Within 16 h after ingestion of 240 mg PABA at recommended hours the lowest acceptable recovery (78.1%) was reached. CONCLUSION: There is a gradual decline of PABA recovery with age that cannot be overcome by advancing the dosage schedule. Because of a lower delimiting PABA recovery for the elderly, some 24 h collections in this age group will be rejected unjustly (false-negatives). Also, with the currently recommended dosage schedule (PABA taken with the main meals) the risk of false-positive 24 h urine collections prevails. With refinement of the PABA test procedure, ie employing a specific analytical method and age-dependent cut-off values, the test may achieve a higher specificity and sensitivity.

4-Aminobenzoic Acid↗
PubMed2003

Factors associated with the development of chorioretinal atrophy around choroidal neovascularization in pathologic myopia.

PURPOSE: To examine the influencing factors on the development of chorioretinal atrophy, which is the main cause of long-term visual decrease in myopic choroidal neovascularization (CNV), in a large series of highly myopic patients. METHODS: Sixty-five patients (81 eyes) with myopic CNV were studied retrospectively. The influence of the patient's age, refractive error, axial length, visual acuity at onset of CNV, size of CNV, and grade of myopic retinopathy on the extent of chorioretinal atrophy more than 3 years after CNV onset was investigated by means of multiple linear regression analysis. RESULTS: Seventy-seven of 81 eyes (95.1%) developed chorioretinal atrophy around myopic CNV during the follow-up period. Multiple linear regression revealed that age was the most influencing factor for the development of chorioretinal atrophy in all the subjects. When we divided the subjects into two groups according to their age, however, CNV size was the only factor to influence the development of chorioretinal atrophy in the patients younger than 40 years, whereas age was still the only influencing factor in those older than 40 years. CONCLUSIONS: The factors influencing the development of chorioretinal atrophy differ according to patient age. Local factors, such as CNV size, determine the tendency to develop chorioretinal atrophy in young patients. Systemic factors, such as patient age, play a greater part in older subjects.

Atrophy↗
PubMedDate not supplied

Relationship between astigmatism and aging in middle-aged and elderly Japanese.

PURPOSE: To study the effect of aging on astigmatism in adult Japanese. METHODS: Measurements of refractive errors and keratometry were performed on 2161 randomly selected subjects (aged 40-79 years). The relation between age and the net value in diopters (D) of astigmatism was evaluated with a trend test. The relation between age and the polar value was also examined by linear regression analysis. RESULTS: The mean (+/-SD) value of total and corneal astigmatism was -0.97 +/- 0.72 D and -0.86 +/- 0.63 D, respectively, and the net value of both increased with age (P trend < 0.001). The prevalence of either type of astigmatism also increased with age, according to the Cochran-Mantel-Haenzel test (P < 0.0001 for total and P < 0.01 for corneal astigmatism). The prevalence of against-the-rule astigmatism increased with age for either type of astigmatism (P < 0.0001 for total, P < 0.0001 for corneal). According to the analysis of polar values by age, the regression coefficient (+/-SE) for total and corneal astigmatism was -0.024 +/- 0.002 (P < 0.0001) and -0.028 +/- 0.002 (P < 0.0001), respectively. There was no statistical difference between these two regression coefficients. CONCLUSIONS: The prevalence of astigmatism increases and the axis turns to against-the-rule with age. The result of the linear regression analysis indicates that the age-related change in astigmatism is mainly associated with changes in the cornea.

Adult↗
PubMed2005

Independent association between leptin and blood pressure during third trimester in normal and gestational diabetic pregnancies.

OBJECTIVE: To assess the relationship between plasma leptin concentration during third trimester of pregnancy and blood pressure, independent of body mass index at examination and other potential confounders. STUDY DESIGN: A cross-sectional study was performed including 95 women (61 non-diabetic women, 34 women with gestational diabetes (GD)) in their third trimester of pregnancy. The relationship between plasma leptin and blood pressure was investigated using multiple linear regression analysis. RESULTS: Independent of body mass index (BMI), leptin was positively correlated to systolic (P = 0.024) and diastolic blood pressure (P = 0.002). Stepwise linear regression identified leptin as the only variable independently associated with systolic blood pressure (P = 0.003), while leptin (P < 0.001) and age (P = 0.024) were the only variables independently correlated to diastolic blood pressure. CONCLUSIONS: This study reports for the first time that, independent of BMI at examination, presence of GD or other confounders, plasma leptin is positively correlated with blood pressure in pregnant women.

Blood Pressure↗
PubMed2002

Clinical predictors of response to lamotrigine and gabapentin monotherapy in refractory affective disorders.

BACKGROUND: The objective of the current study was to examine possible clinical predictors of positive response to lamotrigine or gabapentin monotherapy in treatment-refractory affectively ill patients. METHODS: Forty-five patients with treatment refractory bipolar (n = 35) or unipolar (n = 10) affective disorder participated in a clinical study evaluating six weeks of treatment with lamotrigine, gabapentin, or placebo monotherapy given in a double-blind, randomized fashion with two subsequent cross-overs to the other agents. Patients received daily mood ratings and weekly cross-sectional scales. Much or very much improved on the Clinical Global Impression scale modified for bipolar illness was considered a positive response. Degree of response was correlated with a number of baseline demographic and course of illness variables in a univariate analysis and then by linear regression. RESULTS: Response rates to lamotrigine (51%) exceeded those to gabapentin (28%) and placebo (21%). A positive response to lamotrigine monotherapy was associated with a bipolar diagnosis; fewer hospitalizations; fewer prior medication trials; and male gender (of which the latter two variables survived logistic regression). For gabapentin, degree of response correlated with shorter duration of illness; younger age; and lower baseline weight (with the latter two surviving linear regression). CONCLUSIONS: In this highly treatment-refractory population, lamotrigine appeared most effective for male patients with fewer prior medication trials. Gabapentin monotherapy, although not better than placebo, appeared most effective in those with younger age and lower baseline weight. These preliminary data in a treatment refractory subgroup may help in the further definition of the range of clinical utility of these widely used anticonvulsants.

Acetates↗
PubMed2003

A topological-substructural molecular design (TOPS-MODE) approach to determining pharmacokinetics and pharmacological properties of 6-fluoroquinolone derivatives.

The topological-substructural molecular design approach was used to estimate the human bioavailability (F) and the minimum inhibitory concentration (MIC90) against Streptococcus pneumoniae from a data set of 17 and 19 fluoroquinolone derivatives, respectively. Both pharmacokinetics and pharmacological properties were well described by the present approach. The total spectral moments and local spectral moments that include the different fluoroquinolone rings, polar and non-polar areas and their interactions were calculated and weighted with the standard dipole moments and the electronegative difference between the atoms that form a bond. In order to obtain a qualitative model that permits the classification of drugs with high and moderate bioavailability, a linear discriminant analysis was carried out. The percentage of correct classification was 100% for compounds of the training set. The leave-one-out cross validation procedure showed an 88.23% of correct classification. Also, a quantitative model, by the piecewise linear regression was developed. The theoretically predicted values for human bioavailability was assessed by a correlation with in vivo rat bioavailability and the regression equation was used to predict this biopharmaceutical property for two new pre-clinical 6-fluoroquinolone derivatives. On the other hand, a linear regression model that explained the 84% of variance was developed to predict the MIC90 values. Finally, the role of a pharmacokinetic and pharmacological relationship in the design of new fluoroquinolones was evaluated in the Sitafloxacin framework, where 13 substituents were analyzed; halogens and methoxy groups had the best contributions to both properties. The present approach proved to be a good method for studying the pharmacokinetics and the pharmacological properties of new 6-fluoroquinolone candidates in drug development studies.

Animals↗
PubMed2003

Diabetes mellitus and cognitive performance in older women.

PURPOSE: This cross-sectional study sought to identify diabetes accurately in a study population of 3681 women age 75 and older and to determine the association of diabetes with cognitive performance. METHODS: A previously validated test, the Telephone Interview of Cognitive Screening-Modified (TICSm) was given to assess cognitive status. A diabetes case identification database, medical record review and self-report were used to determine diabetes cases. 489 (13.3%) of the women in the study were classified with diabetes and 3192 without diabetes. RESULTS: t-tests and linear regression analyses determined that diabetic women had a mean TICSm score 1.4 points lower (i.e. more impaired) than non-diabetic women. Using linear regression to adjust for age, education, and vascular disease, diabetic women showed a 1.1 lower score on the TICSm. Similar adjustments were made for potential confounding variables such as depression, hormone replacement therapy (HRT), high body weight, smoking, alcohol use and exercise and diabetics again showed a 1.0 lower score. CONCLUSION: This study, which utilizes highly rigorous case identification methodology, provides further evidence that diabetes is associated with significantly worse cognitive performance in the elderly.

Aged↗
PubMed1994

On-site prothrombin time, activated partial thromboplastin time, and platelet count. A comparison between whole blood and laboratory assays with coagulation factor analysis in patients presenting for cardiac surgery.

BACKGROUND: Although available hemostasis assays from institutional laboratories permit an analytical approach to diagnosis and treatment of coagulation disorders following cardiopulmonary bypass, their clinical utility has been limited by delays in obtaining results. The development of instrumentation for on-site testing allows rapid return of results. This study was designed to compare whole blood (WB) results obtained from on-site coagulation assays with values provided by our institutional laboratory (LAB). METHODS: After Institutional Human Studies Committee approval, 362 patients presenting for cardiac surgery requiring cardiopulmonary bypass were enrolled in this study. Prothrombin time (PT), activated partial thromboplastin time (aPTT), and platelet count (PLT) assays were performed in both WB and LAB systems. PT, aPTT, and PLT measurements were compared between WB and LAB assays using blood specimens obtained from at least two time points for each patient. Normal range values for both PT and aPTT methods were determined by using measurements from a normal reference population. Coagulation factor levels were measured in a subset of patients to characterize the response of PT and aPTT assays to individual and multiple factor levels. To employ Bayes' theorem and calculate predictive indexes (e.g., sensitivity, specificity), the disease or factor deficiency was determined using factor levels. Predictive indexes were used to evaluate the ability of PT and aPTT assays to identify factor deficiency. RESULTS: PLT counts were similar between systems. Linear regression and bias analysis demonstrated similar results for WB and LAB PT and discordant results for aPTT measurements. Both PT assays had a similar normal range, whereas a wider distribution of results was evident for the WB aPTT normal range. Although statistically greater slopes for factor:aPTT regressions were observed for the WB system, WB aPTT correlated better with factor V and with factor V, VIII, and XII levels (multivariate linear regression). Diagnostic performance for factor levels less than 0.3 and 0.4 U/ml was similar for both WB and laboratory PT and aPTT assays. WB and LAB PT and aPTT assays performed similarly in detecting factor deficiency in the period after cardiopulmonary bypass. CONCLUSIONS: WB PT and PLT values correlate well with those obtained from the LAB. The discrepancy between measurement systems in aPTT values is probably a reflection of both different normal ranges and responsiveness to factor deficiency. These WB assays provide coagulation results that can accurately identify patients with quantitative deficiencies in platelets and coagulation factors.

Adult↗
PubMed1994

Kinetic study of atrial natriuretic peptide in patients with idiopathic dilated cardiomyopathy: evidence for resistance to biologic effects of the hormone even in patients with mild myocardial involvement.

Atrial natriuretic peptide (ANP) kinetics was studied in 12 patients with idiopathic dilated cardiomyopathy at different sodium excretion (30-175 mmol/day) and variable degrees of hemodynamic dysfunction [New York Heart Association (NYHA) class range I-III] to investigate whether differences in renewal and distribution of this hormone (as compared with those of a control group) play a role in pathogenesis and evolution of heart failure. [125I]Labeled ANP was injected as a bolus, and a high-performance liquid chromatography (HPLC) procedure was used to purify the labeled hormone in venous plasma samples collected for < or = 50 min after injection; the main ANP kinetic parameters were then derived from the disappearance curve of the labeled hormone. As in controls, a positive linear regression between ANP metabolic clearance rate (MCR, ml/min/m2) values and daily urinary excretion of sodium (NaUE, mmol/day) was noted in patients. The different linear regression coefficients between normal subjects (MCR = 365 +/- 8.08 NaUE, r = 0.986, p < 0.0001) and patients (MCR = 497 + 18.5 NaUE, r = 0.867, p = 0.001) indicate that in patients a higher peptide clearance rate is needed to obtain the same biologic effect (sodium excretion) and suggest that resistance to biologic effects of the hormone exists in patients at an early stage of disease (NYHA class I). When the efficiency of the ANP system in excreting sodium was expressed as the ratio of NaUE to ANP production rate (PR = MCR x ANP plasma concentration, microgram/day/m2) patients showed significantly lower values (p = 0.0126) than normal volunteers, thus confirming resistance to the hormone effects. Significantly lower values for ANP total distribution volume (16.5 +/- 8.4 L/m2), mean residence time in the sampling space (4.04 +/- 1.14 min), mean residence time in the body (7.25 +/- 2.13 min), and fewer recycles through the initial (sampling) space (0.27 +/- 0.16) were noted in patients, indicating an altered mechanism regulating distribution of the hormone. The positive correlations between ANP MCR (L/min/m2) values and cardiac index (CI, L/min/m2) (MCR = -1.24 + 1.17 CI, r = 0.689, p = 0.0092) and between initial distribution volume (IDV, L/m2) and CI (IDV = -11.2 + 6.85 CI, r = 0.730, p = 0.0046) in all patients indicate that hemodynamic factors contribute to the progressive reduction in MCR and IDV values throughout the progression of myocardial involvement.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed2004

Salivary secretory leukocyte protease inhibitor and oral candidiasis in human immunodeficiency virus type 1-infected persons.

Oropharyngeal candidiasis, typically caused by Candida albicans, is the most common oral disease associated with human immunodeficiency virus type 1 (HIV-1) infection. Secretory leukocyte protease inhibitor (SLPI), a 12-kDa antiprotease, suppresses the growth of C. albicans in vitro. To determine whether the mucosal protein plays a role in protecting oral tissues against fungal infection, we conducted a cross-sectional study investigating the oral and systemic health and salivary SLPI levels in 91 dentate HIV-1-infected adults receiving medical care in the southeastern United States. Participants with a self-reported history of clinical oropharyngeal candidiasis during the previous 2 years constituted the test group (n = 52), while the comparison group (n = 39) had no oropharyngeal candidiasis during that period. Data collected from medical records, oral examination, and SLPI enzyme-linked immunosorbent assay quantitation of whole saliva were analyzed by t test, analysis of variance, linear regression, and unconditional logistic regression. The test group had a significantly higher mean salivary SLPI level than the comparison group (1.9 microg/ml versus 1.1 microg/ml, P < 0.05). Linear regression modeling identified CD4 cell count and history of oropharyngeal candidiasis as key predictors of salivary SLPI and revealed a significant interaction (P < 0.05) between immunosuppression (CD4 cell count below 200 cells/ microl) and positive history of oropharyngeal candidiasis in predicting salivary SLPI level. By logistic regression modeling, a salivary SLPI level exceeding 2.1 microg/ml, low CD4 count, antiretroviral monotherapy, and smoking were key predictors of oropharyngeal candidiasis. These data support a key role for SLPI in the oral mucosal defense against C. albicans. The antimicrobial mucosal protein may serve as an indicator of previous oropharyngeal candidiasis infection among immunosuppressed persons.

AIDS-Related Opportunistic Infections↗
PubMed2006

Statistical analyses of correlation between fluconazole MICs for Candida spp. assessed by standard methods set forth by the European Committee on Antimicrobial Susceptibility Testing (E.Dis. 7.1) and CLSI (M27-A2).

The European Committee on Antimicrobial Susceptibility Testing (EUCAST) Subcommittee on Antifungal Susceptibility Testing recently published a standard for determining the susceptibility of fermentative yeasts to antifungals. From the beginning, the EUCAST and its North American counterpart, the CLSI, decided to work together in order to establish common standards. As part of this exercise, the susceptibility of a set of 475 yeast isolates was tested by both standards. The intraclass correlation coefficient and the equations defining the linear regression between both methods were estimated. Both methods produced very similar results, with an intraclass correlation coefficient of 0.954 (0.945 to 0.962), although linear regression analysis shows that the EUCAST standard resulted in slightly lower MICs. There were only eight isolates showing at least four twofold dilution MIC differences between both standards. After 24 h of incubation, the MICs obtained by the CLSI method were equivalent to those obtained by the EUCAST standard. In summary, both methods produce very similar MICs, indicating that methodology does not pose any obstacle to obtaining uniform standards for antifungal susceptibility testing of yeasts.

Antifungal Agents↗
PubMed2001

The relationship of penile rigidity and intracavernous vascular resistance in potent men during intracavernous pharmacological testing.

PURPOSE: We studied the relationship of penile rigidity and intracavernous vascular resistance in potent men during intracavernous pharmacological testing. MATERIALS AND METHODS: Enrolled in our study were 19 potent men undergoing intracavernous pharmacological testing for various reasons. Hemodynamic changes in response to the intracavernous injection of 20 microg. prostaglandin E1 were assessed by color Doppler sonography with simultaneous RigiScan (Dacomed Corp., Minneapolis, Minnesota) monitoring of penile rigidity. The relationship of penile rigidity and intracavernous vascular resistance was determined by correlating hemodynamic data with recorded penile rigidity values. RESULTS: Maximal mean rigidity plus or minus standard deviation of the penile tip and base after intracavernous injection of prostaglandin E1 was 76.8% +/- 8.5% and 97.3% +/- 4.7%, respectively. Penile tip and base rigidity correlated positively with the resistive index (r = 0.69 and 0.75, p <0.0001) and negatively with end diastolic velocity (r = -0.62 and -0.70, respectively, p <0.0001). The formula, rigidity = -128 + 195 x resistive index, was derived to describe the linear regression of penile base rigidity and the resistive index. The formula, rigidity = 59.8 - 3.3 x end diastolic velocity, was derived to describe the linear regression of penile base rigidity and end diastolic velocity. CONCLUSIONS: Penile rigidity correlated strongly with intracavernous vascular resistance in potent men during intracavernous pharmacological testing. The resistive index and end diastolic velocity of the cavernous arteries may each be used to estimate penile rigidity quantitatively.

Adult↗
PubMed1995

Automated discrimination and quantification of idiopathic pulmonary fibrosis from normal lung parenchyma using generalized fractal dimensions in high-resolution computed tomography images.

RATIONALE AND OBJECTIVES: We computed generalized fractal dimensions for high-resolution computed tomography (HRCT) images to investigate their value in the discrimination and quantification of idiopathic pulmonary fibrosis (IPF) from normal lung parenchyma. METHODS: A probability distribution that was based on the pixel value in each image was used to compute capacity, information, and higher fractal dimensions for a series of 52 HRCT slices obtained from four patients. Qualitative classification of normal, mild, moderate, and severe IPF cases was achieved by computing the following parameter: DD = D0 - 2D1 + D2, where D0, D1, and D2 represents the capacity, information, and pair correlation dimensions, respectively. A multiple linear regression analysis using morphometric quantification for the set of 52 slices was tested for all possible combinations of the parameters D0, D1, D2, and D3. The generalizability of the model was tested by predicting the extent of IPF for each patient from a regression model computed with the remaining slices in the database. RESULTS: The best regression results were obtained using the independent parameters D1 and D2 to quantify the extent of diseased lung parenchyma. The technique was tested with 48 slices from 12 new patients. The results indicated that the extent of IPF could be predicted within the confidence limits given by the regression analysis. CONCLUSION: The extent of IPF can be predicted well within the 90% confidence interval given by the model. The width of the confidence interval decreases as the number of slices used in the linear regression model increases. This operator-independent quantitative technique may be useful in the follow-up of patients with IPF.

Confidence Intervals↗