A semi-automatic method for quantification and classification of erythrocytes infected with malaria parasites in microscopic images

Visual quantification of parasitemia in thin blood films is a very tedious, subjective and time-consuming task. This study presents an original method for quantification and classification of erythrocytes in stained thin blood films infected with Plasmodium falciparum. The proposed approach is composed of three main phases: a preprocessing step, which corrects luminance differences. A segmentation step that uses the normalized RGB color space for classifying pixels either as erythrocyte or background followed by an Inclusion-Tree representation that structures the pixel information into objects, from which erythrocytes are found. Finally, a two step classification process identifies infected erythrocytes and differentiates the infection stage, using a trained bank of classifiers. Additionally, user intervention is allowed when the approach cannot make a proper decision. Four hundred fifty malaria images were used for training and evaluating the method. Automatic identification of infected erythrocytes showed a specificity of 99.7% and a sensitivity of 94%. The infection stage was determined with an average sensitivity of 78.8% and average specificity of 91.2%.     

Continuous subcutaneous insulin infusion is more effective than multiple daily insulin injections in preventing albumin excretion rate increase in Type 1 diabetic patients

Aims To compare the effect of continuous subcutaneous insulin infusion (CSII) and multiple daily insulin injections (MDI) on albumin excretion rate (AER) in Type 1 diabetic patients. Methods In a 3‐year multicentre retrospective observational study, 110 Type 1 diabetic patients treated with CSII were compared with 110 patients treated with MDI matched at baseline for age, sex, diabetes duration and HbA_1c. At entry, 90 patients in each group had normal AER and 20 persistent microalbuminuria. AER, estimated glomerular filtration rate (eGFR), HbA_1c, lipids and blood pressure were assessed. Results HbA_1c was lower in the CSII than in the MDI group (8.1 ± 0.9 vs. 8.4 ± 1.3%; P < 0.005 after 3 years). Blood pressure and eGFR were similar during the study. AER [median (95% confidence interval)], similar at baseline [6.0 μg/min (9, 21) in the CSII group vs. 4.4 (8, 16) in the MDI group, NS] was significantly lower in the patients treated with CSII both at year 2 and at year 3 of follow‐up [4.7 μg/min (6, 12) vs. 6.4 (13, 29), P < 0.002]. This difference was observed even when normo‐ and microalbuminuric patients were analysed separately. Nine patients progressed to microalbuminuria in the MDI group and only one in the CSII group. Nine patients regressed to normoalbuminuria in the CSII group, whereas only two regressed to normoalbuminuria in the MDI group. Conclusions Despite a small benefit in terms of improved glycaemic control, CSII therapy may be useful in decreasing the progressive increase in AER in Type 1 diabetic patients.     

In vitro study of P-glycoprotein induction as an antidotal pathway to prevent cytotoxicity in Caco-2 cells

The Caco-2 cell line is a reliable in vitro model for predicting drug intestinal absorption and P-glycoprotein (P-gp)-mediated excretion in humans. Recent in vivo studies suggested the induction of P-gp as a cellular protection tool against paraquat poisoning, through the increase in its pulmonary and intestinal excretion. Thus, the aim of the present work was to evaluate P-gp expression and activity in Caco-2 cells exposed to doxorubicin (a known P-gp inducer) and to correlate these changes with paraquat toxic effects. Cytotoxicity of doxorubicin (0–100 μM) and paraquat (0–1,000 μM) was evaluated for a maximum period of 96 h. In doxorubicin-exposed cells, P-gp expression and transport activity were evaluated by flow cytometry, using a fluorescein isothiocyanate–conjugated antibody and the P-gp fluorescent subtract rhodamine 123, respectively. A significant increase in P-gp expression was observed as soon as 6 h after exposure to 5 μM doxorubicin. P-gp activity also increased after 6 h, but only at higher doxorubicin concentrations (over 50 μM). Paraquat (0–5,000 μM) cytotoxicity was then evaluated with or without previous exposure of the cells to doxorubicin (5–100 μM, a concentration range causing both an increase in P-gp expression and activity). Under P-gp induction, a significant reduction in paraquat cytotoxicity was observed. Furthermore, when these cells were incubated with a specific P-gp inhibitor (UIC2 antibody) the doxorubicin protective effects were blocked, confirming the involvement of P-gp in the reduction in paraquat cytotoxicity. In conclusion, the human Caco-2 cell line model can be used for the study of P-gp induction as an antidotal pathway against substrates of this transporter system.     

ORIGINAL RESEARCH – OUTCOMES ASSESSMENT: Female Sexual Well-Being Scale™ (FSWB Scale™): Development and Psychometric Validation in Sexually Functional Women

IntroductionNo validated instrument exists for measuring female sexual well-being (FSWB?) in women without medical/psychosocial conditions.AimsTo develop and psychometrically validate a self-administered Female Sexual Well-Being Scale? (FSWB Scale?) for assessing sexual well-being in sexually functional women.MethodsImportant aspects of FSWB? were identified via focus groups, debriefing interviews, and administration of an initial scale to 111 US women aged 21–72 years reporting normal sexual function (Female Sexual Function Index >26). Principal components analysis and psychometric validity testing of a FSWB Scale? were conducted in a second study of 332 women.Main Outcome MeasuresTo develop a FSWB Scale, based on qualitative input from women reporting normal sexual function, and determine its factor structure and psychometric validity.ResultsFour aspects of FSWB were identified from the qualitative research. Women's preferred language to describe sexual well-being and preferred response formats were incorporated into the scale. A principle components analysis of quantitative study data from 332 women aged 21–72 years reporting normal sexual function identified 5 factors with eigenvalues >1: interpersonal domain (6 items), cognitive-emotional domain (5 items), physical arousal domain (3 items), orgasm-satisfaction domain (3 items), and external lubrication domain (2 items). The external lubrication domain did not demonstrate strong positive correlations with the other 4 domains, so it was not retained in the final scale. A high degree of internal consistency was demonstrated for the 4 domains (Cronbach's alpha values: 0.84–0.92). Test-retest reliability over a 2-week period was high (r > 0.80) or moderately high (r > 0.70) for the 4 domain scores. Correlation coefficients between FSWB Scale domain scores and standardized scale scores for female sexual function, depression, and social desirability demonstrated the construct validity of the FSWB Scale.ConclusionA 17-item FSWB Scale was developed and psychometrically validated as a reliable, multidimensional, self-administered instrument for assessing sexual well-being in women of different ages. Rosen RC, Bachmann GA, Reese JB, Gentner L, Leiblum S, Wajszczuk C, and Wanser R. Female Sexual Well-Being Scale? (FSWB Scale?): Development and psychometric validation in sexually functional women. J Sex Med 2009;6:1297–1305.     

Excess weight and associated risk factors in patients with systemic lupus erythematosus

The objective of this study is to determine the socio-demographic, clinical and laboratory characteristics of outpatients with SLE who present with excess weight as well as to assess the immunosuppressive therapy used. One hundred and seventy women with SLE were evaluated consecutively in a transversal study. The relationship between excess weight and the patients’ characteristics was evaluated using univariate and multivariate Poisson regression analysis. Of the 170 patients evaluated, 109 presented with excess weight, two were malnourished and 59 were classified as eutrophic. Age and disease duration of those with excess weight were 42.4 ± 8.7 and 10.4 ± 6.2 years, respectively. Risk factors associated with excess weight were the following: age ≥40 years, <8 years of education, lack of occupation, damage index ≥1, systemic high blood pressure, diabetes mellitus and triglycerides ≥150 mg/dL levels. The use of antimalarial therapy and steroids was associated with a lower frequency of excess weight. Age ≥40 years and the non-usage of methotrexate were the variables independently associated with excess weight in the multivariate analysis. Patients with SLE who have excess weight present distinct clinical-laboratory findings, socio-demographic characteristics and treatment options when compared to normal weight patients. Prospective studies should assess whether these characteristics will interfere with the outcome or prognosis of lupus.