Machine learning models for the differential diagnosis of vascular parkinsonism and Parkinson's disease using [(123)I]FP-CIT SPECT.

PURPOSE: The study's objective was to develop diagnostic predictive models using data from two commonly used [(123)I]FP-CIT SPECT assessment methods: region-of-interest (ROI) analysis and whole-brain voxel-based analysis. METHODS: We included retrospectively 80 patients with vascular parkinsonism (VP) and 164 patients with Parkinson's disease (PD) who underwent [(123)I]FP-CIT SPECT. Nuclear-medicine specialists evaluated the scans and calculated bilateral caudate and putamen [(123)I]FP-CIT uptake and asymmetry indices using BRASS software. Statistical parametric mapping (SPM) was used to compare the radioligand uptake between the two diseases at the voxel level. Quantitative data from these two methods, together with potential confounding factors for dopamine transporter availability (sex, age, disease duration and severity), were used to build predictive models following a tenfold cross-validation scheme. The performance of logistic regression (LR), linear discriminant analysis and support vector machine (SVM) algorithms for ROI data, and their penalized versions for SPM data (penalized LR, penalized discriminant analysis and SVM), were assessed. RESULTS: Significant differences were found in the ROI analysis after covariate correction between VP and PD patients in [(123)I]FP-CIT uptake in the more affected side of the putamen and the ipsilateral caudate. Age, disease duration and severity were also found to be informative in feeding the statistical model. SPM localized significant reductions in [(123)I]FP-CIT uptake in PD with respect to VP in two specular clusters comprising areas corresponding to the left and right striatum. The diagnostic predictive accuracy of the LR model using ROI data was 90.3 % and of the SVM model using SPM data was 90.4 %. CONCLUSION: The predictive models built with ROI data and SPM data from [(123)I]FP-CIT SPECT provide great discrimination accuracy between VP and PD. External validation of these methods is necessary to confirm their applicability across centres.

Effect of bariatric surgery on microvascular dysfunction associated to metabolic syndrome: a 12-month prospective study.

OBJECTIVE: To prospectively evaluate the effect of weight loss after bariatric surgery on microvascular function in morbidly obese patients with and without metabolic syndrome (MetS). METHODS: A cohort of morbidly obese patients with and without MetS was studied before surgery and after 12 months of surgery. Healthy lean controls were also examined. Microvascular function was assessed by postocclusive reactive hyperemia (PORH) at forearm skin evaluated by laser Doppler flowmetry (LDF). Cutaneous vascular conductance (CVC) was calculated from laser-Doppler skin blood flow and blood pressure. Regression analysis was performed to assess the contribution of different clinical, metabolic and biochemical parameters to microvascular function. RESULTS: Before surgery, 62 obese patients, 39 with MetS and 23 without MetS, and 30 lean control subjects were analyzed. The absolute area under the hyperemic curve (AUC(H)) CVC of PORH was significantly decreased in obese patients compared with lean control subjects. One year after surgery, AUC(H) CVC significantly increased in patients free of MetS, including patients that had MetS before surgery. In contrast, AUC(H) CVC did not significantly change in patients in whom MetS persisted after surgery. Stepwise multivariate regression analysis showed that only changes in HDL cholesterol (HDL-C) and oxidized LDL (oxLDL) independently predicted improvement of AUC(H) after surgery. These two variables together accounted for 40.9% of the variability of change in AUC(H) CVC after surgery. CONCLUSIONS: Bariatric surgery could significantly improve microvascular dysfunction in obese patients, but only in patients free of MetS after surgery. Improvement of microvascular dysfunction is strictly associated to postoperative increase in HDL-C levels and decrease in oxLDL levels.

Brain function in the minimally conscious state: a quantitative neurophysiological study.

OBJECTIVE: To explore possible EEG power spectrum and coherence differences between patients in minimally conscious state (MCS) and patients with severe neurocognitive disorders (SND), who show signs of awareness. We also try to find EEG cortical sources that differentiate between both conditions using LORETA source analysis. METHODS: We studied 16 patients with traumatic brain injury (7 MCS, 9 SND; aged 18-49) and compared EEG power spectra, coherence, and LORETA sources at rest for both groups. RESULTS: EEG power spectra revealed significant differences in the delta range of both conditions. Patients in MCS showed a notably increased power in this band, compared to SND patients. LORETA analysis showed that posterior sources of delta and theta frequencies had higher amplitude in MCS patients than in SND patients. Regarding fast frequencies, lower source magnitudes in temporal and frontal lobes were found for MCS patients. CONCLUSIONS: Our results stress the importance of fronto-temporal-parietal associative cortices within the "awareness-regions" model. Our results also suggest a relation between excess of slow wave activity and diminished level of awareness in brain injury population. SIGNIFICANCE: Neurophysiological correlates in brain damaged patients who are severely impaired could be used to assess the integrity of brain areas responsible for awareness.

Identification of species of Brucella using Fourier transform infrared spectroscopy.

Fourier transform infrared spectroscopy (FTIR) is a technique that has been used over the years in chemical analysis for the identification of substances and is one that may be applied to the characterisation of microorganisms. The marked tendency of Brucella towards variation in the smooth rough phase, together with the laboriousness and risk involved in the methods used in their identification, make their classification difficult. We studied the type strains of the different species and biovars of Brucella and 11 isolates of human origin of Brucella melitensis, six corresponding to biovar 1, one to biovar 2 and five to biovar 3. The results of linear discriminant analysis performed using the data provide an above 95% likelihood of correct classification, over half of which are in fact above 99% for the vast majority of Brucella strains. Only one case of B. melitensis biovar 1 has been incorrectly classified. The rest of the microorganisms studied (Staphylococcus aureus, Strteptococcus pyogenes, Enterococcus faecalis, Corynebacterium pseudodiphtheriticum, Clostridium perfringens, Escherichia coli, Acinetobacter calcoaceticus and Pseudomonas aeruginosa) have been classified correctly in all cases to a likelihood of over 80%. In the graphic representation of the analysis, a grouping of these can be seen in clusters, which include the different species. One of these comprises B. melitensis, another Brucella abortus, and another wider one is made up of Brucella suis. The Brucella canis, Brucella ovis and Brucella neotomae strains appear separate from the previously described groups.

[Inflammation and infection in stable coronary disease and acute coronary syndrome]. / Inflamación e infección en la enfermedad coronaria estable y en el síndrome coronario agudo.

OBJECTIVE: To study whether inflammation and infection are related to coronary artery disease. DESIGN: Sixty patients (44 males, mean age 62 +/- 13 years) with acute coronary syndrome and 40 with stable coronary artery disease (31 males, age 64 +/- 10 years) and a control group of 40 individuals (34 males, 53 +/- 5 years) were analyzed. IgG against Chlamydia pneumoniae, Cytomegalovirus and Helicobacter pylori plus C-reactive protein were assessed in all serum samples. In addition, IgM against C. pneumoniae and Cytomegalovirus on admission and C-reactive protein one month later were measured in acute patients. RESULTS: No IgM seropositivity was observed. A high prevalence of IgG seropositivity with no significant differences among the groups was found: C. pneumoniae: acute group 44 (73%), stable group 29 (73%) and control group 25 (63%); Cytomegalovirus: 55 (92%), 37 (92%) and 38 (95%), respectively; and H. pylori, 43 (72%), 32 (80%) and 34 (85%) respectively. There was a high rate of positive C-reactive protein in the acute group: 48 (80%) vs 10 (25%) the stable group and 0% the control group (p < 0.001). C-reactive protein levels were higher in Q-wave infarction than in unstable angina/ non-Q-wave infarction (median 22.65 vs 7.69, p < 0.001). One month later, C-reactive protein levels decreased (median 22.65 vs 3.38, p < 0.001), but were still positive in 40%. CONCLUSIONS: These data suggest that inflammation is detected by the commonly used methods in clinic practice in acute coronary syndromes and to a lesser extent in stable coronary artery disease. It seems that different mechanisms other than infection account for this inflammatory response, at least this being so when infection is assessed by serology. Serology does not appear to be an adequate method to determine the possible relationship among coronary syndromes, infection and inflammation.

Influence of syphilis in hepatitis B transmission in a cohort of female prostitutes.

BACKGROUND AND OBJECTIVES. Prostitutes are a greater risk for hepatitis B virus (HBV) infection than the general population. We studied the influence of age and time as prostitute on HBV infection. We also examined the relationship between syphilis and HBV infection in a cohort of female prostitutes. STUDY DESIGN. The presence of hepatitis B surface antigen (HBsAg), antibodies to hepatitis B core antigen (anti-HBc), antibodies to hepatitis D virus (anti-HD) and treponemal antibodies (FTA-ABS) were determined in 368 prostitutes, of whom 147 were submitted to medical and serological follow-up every six months to evaluate the influence of syphilis in the transmission of hepatitis B. RESULTS AND CONCLUSION. The prevalence of HBsAg was 4.6%, of anti-HBc 31.2%, anti-HD 0.5% and FTA-ABS 35.0%. There was a statistical association between the presence of treponemal antibodies and anti-HBc (P = 0.022). The cohort study performed shows that the accumulated incidence of HBV infection in the FTA-ABS positive prostitutes (24.6%) was significantly higher than that of the FTA-ABS negative group (9.7%) (RR = 2.544; P = 0.034). Our results indicate that syphilis could facilitate the heterosexual transmission of HBV infection.

[Influence of parity and legitimacy on late fetal mortality in Castilla-León]. / Análisis de la influencia de la paridad y legitimidad sobre la mortalidad fetal tardía de Castilla-León.

Biological and social factors affecting of late fetal death (LFD), made up by those dead births of twenty eight or more weeks gestation, are studied. Influence of parity (birth order) and civil status of mother (single, married) are analysed in Castilla-León during 1975-1979 through Logit models. Between the hierarchical non permeated models, considered before, it was choose the one made out of (parity X status) (year). If we make a detailed fitting, civil status as main effect is eliminated, obtaining a new model: (parity) (year) (parity X status). A constant tendency to decrease LFD during the studied years is observed. It is pointing out the importance of the whole study, about parity and civil status, as an explanatory factor of this mortality.

[Effectiveness of a clinical test in the preselection of children with suspected fragile X syndrome]. / Eficacia de un test clínico como preselección de niños con sospecha de síndrome X frágil.

BACKGROUND: Fragile X syndrome (FXS) is the most frequent hereditary cause of mental retardation. It can be diagnosed by molecular genetic techniques, but clinical suspicion is made less likely by it variable expression. OBJECTIVE: To assess the effectiveness of a six-item checklist in the preselection of children who are candidates for FXS genetic study. MATERIAL AND METHODS: We studied 70 male patients aged between 2 and 10 years with mental retardation of unknown cause. In all patients a checklist with six clinical criteria (mental retardation, history of familial mental retardation, long face, large ears, autistic-like behaviour, and attention deficit disorder with hyperactivity) measured from 0-2 points was applied and molecular genetic studies using polymerase chain reaction and Southern-blot were performed. RESULTS: In 14 of the 70 children (20%) molecular study confirmed full mutation (200 CGG repeats). A score of six points in the test had the greatest discriminatory power and was reached by 14 patients (100%) with mutation, but only by 2of 56patients (3.5%) without mutation. The most accurate diagnostic model was the association of mental retardation, attention deficit disorder with hyperactivity, large ears and a history of familial mental retardation followed by long face and autistic-like behaviour. CONCLUSIONS: The six-item checklist improved the preselection of children with suspicion of FXS, which was later confirmed by molecular genetic techniques.

[Antibody titers against the hepatitis A virus in a healthy population from an urban health area]. / Estudio de los títulos de anticuerpos frente al virus de la hepatitis A en una población sana de una zona de salud urbana.

AIMS: To assess the level of immunity in a healthy population to the hepatitis A virus (HAV), according to age groups and in an urban health area. DESIGN: Transversal random prospective study of a sample of the population found by letters. SITE. Primary Care Centre covering the population of an urban health area in Valladolid. PATIENTS OR OTHER PARTICIPANTS: Random sample of 726 people with an adjustment as to sex and age according to the area's average, in line with the full census of the above area. The sample was 95% trustworthy, with a 3% margin of error. People with serious illness at the time of the study were excluded. MEASUREMENTS AND MAIN FINDINGS: We carried out a social-health count. We established the anti-HAV titer after its detection by enzyme immunoanalysis (HAVAB EIA Abbott); the titers were inferred from the absorbances relating then to that of a a "pool" of serums with very high titers. 69.9% (standardised rate) gave positive. The highest titers were presented in people between 31 and 50 (29.7 +/- 47.0), with significant differences both for lower (17.0 +/- 15.7) and higher (15.7 +/- 19.8) age groups (p. 0.001 for both). CONCLUSIONS: The highest anti-HAV titers corresponded to people in the middle age-group, with a subsequent dropping-off. This could suggest a greater susceptibility to HAV infection in the older person.