A study on the image contrast of pseudo-heterodyned scattering scanning near-field optical microscopy.

The dependence of the near-field signal on the dielectric function of a specific material proposes scattering-type near-field optical microscopy (s-SNOM) as a viable tool for material characterization studies. Our experiment shows that specific material identification by s-SNOM is not a straightforward task as parameters involved in the detection scheme can also influence material contrast measurements. More precisely, we demonstrate that s-SNOM contrast in a pseudo-heterodyne detection configuration depends on the oscillation amplitude of the reference mirror and that for reliable measurements of the contrast between different materials this aspect needs to be taken into consideration.

Contrast-enhanced ultrasound (CEUS) for the evaluation of focal liver lesions - a prospective multicenter study of its usefulness in clinical practice.

PURPOSE: To assess the value of contrast-enhanced ultrasound (CEUS) for differentiating malignant from benign focal liver lesions (FLLs) and for diagnosing different FLL types. MATERIAL AND METHODS: CEUS performed in 14 Romanian centers was prospectively collected between February 2011 and June 2012. The inclusion criteria were: age > 18 years; patients diagnosed with 1 - 3 de novo FLLs on B-mode ultrasound; reference method (computed tomography (CT), magnetic resonance imaging (MRI) or biopsy) available; patient's informed consent. FLL lesions were characterized during CEUS according to the European Federation of Societies for Ultrasound in Medicine and Biology guidelines. For statistical analysis, indeterminate FLLs at CEUS were rated as false classifications. RESULTS: A total number of 536 cases were included in the final analysis, 344 malignant lesions (64.2 %) and 192 benign lesions (35.8 %). The reference method was: CT/MRI - 379 cases (70.7 %), pathological exam - 150 cases (27.9 %) and aspiration of liver abscesses - 7 cases (1.4 %). CEUS was conclusive in 89.3 % and inconclusive in 10.7 % of cases. To differentiate between malignant and benign FLLs, CEUS had 85.7 % sensitivity, 85.9 % specificity, 91.6 % positive predictive value, 77.1 % negative predictive value and 85.8 % accuracy. The CEUS accuracy for differentiation between malignant and benign liver lesions was similar in tumors with diameter ≤ 2 cm and those with diameter > 2 cm. CONCLUSION: CEUS represents a useful method in clinical practice for differentiating between malignant and benign FLLs detected on standard ultrasonography, and the results of this study are in concordance with previous multicenter studies: DEGUM (Germany) and STIC (France).

High-resolution quantitative determination of dielectric function by using scattering scanning near-field optical microscopy.

A new method for high-resolution quantitative measurement of the dielectric function by using scattering scanning near-field optical microscopy (s-SNOM) is presented. The method is based on a calibration procedure that uses the s-SNOM oscillating dipole model of the probe-sample interaction and quantitative s-SNOM measurements. The nanoscale capabilities of the method have the potential to enable novel applications in various fields such as nano-electronics, nano-photonics, biology or medicine.

An adult case with onset of celiac disease during chronic hepatitis C antiviral treatment.

We present the case of young women who developed celiac disease during the treatment for chronic hepatitis C. Celiac disease is now considered to be an immune disorder that is triggered by an environmental agent in genetically predisposed persons. Many studies have shown that the total prevalence of gluten sensitive-enteropathy has increased over last decades, and advances in serological screening leads to the idea that there are more celiac disease cases that are asymptomatic and undiagnosed. Actually, pegylated interferonum (IFN) in combination with ribavirine provides the most effective treatment for patient with chronic hepatitis C. However, interferon and ribavirin therapy are associated with induction or exacerbation of preexistent autoimmune disorders.

Are systemic inflammatory profiles different in patients with COPD and metabolic syndrome as compared to those with COPD alone?

BACKGROUND: Metabolic Syndrome (MS) is frequent in patients with COPD, almost 50% of patients with COPD had one or more components of metabolic syndrome (MS). Moreover, it was demonstrated that BMI might be one of the determinants of COPD phenotype. Chronic comorbid diseases affect health outcomes in COPD, in fact, patients with COPD mainly die of non-respiratory disorders such as cardiovascular disease. Inflammation plays a key role in COPD and MS but we do not know the real inflammatory profile of these patients. A better understanding of the origin and consequences of systemic and local inflammation, and of potential therapies, will most likely lead to better care of patients with COPD. METHODS: We compared 64 consecutive, consenting smoker patients with COPD and MS (mean age: 62.7 +/- 0.7 years) with this serum inflammatory profile (hsCRP: 1.9 +/- 0.01 mg/dL, TNF-alpha: 6,4 +/- 0.1 pg/mL, adiponectin: 4.7 +/- 0.01 mg/L) versus 69 COPD smoker patients matched for age (mean age 61.4 +/- 0.4 years) with following serum inflammatory cytokine (CRP: 0.9 +/- 0.01 mg/dL, TNF-alpha: 3.9 pg/mL +/- 0.01, adiponectin: 9.3 +/- 0.01 mg/L). COPD and MS was diagnosed according to the GOLD criteria respectively IFD 2005 criteria. Data were expressed as mean +/- SE (standard error). Comparisons of parameters among the two groups were made by Student unpaired t test. The level of statistical significance was set as p < 0.05. RESULTS: Serum TNF-alpha and high-sensitivity CRP levels in patients with COPD and MS were significantly higher (p < 0.05) than those of COPD alone. Plasma adiponectin levels in patients with COPD were significantly higher (p < 0.05) than in subjects with COPD and MS. CONCLUSIONS: Patients with COPD and MS have a more exacerbated systemic inflammatory profile and a significantly reduced specific adipose response represented by adiponectin than patients with COPD alone. These results help us to better understand the inflammatory pattern in patients with COPD with metabolic disorders and permit us to sustain the regulatory role of adiponectin in metabolism balance. It is possible that this association between COPD and MS with a specific inflammatory pattern (high serum levels of CRP and TNF-a but with low plasma levels of adiponectin) to explain the high rate of death adjudicated as due to cardiovascular causes.

The metabolic and inflammatory profile in obese patients with chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease and obesity are major causes of morbidity and mortality worldwide and, according to current data, the global burden of these conditions will increase further. Obesity plays a major role in the development of the metabolic syndrome and has been identified as an important risk factor for chronic diseases such as type 2 diabetes mellitus and cardiovascular disease. Adiposity is associated with insulin resistance even over relatively normal ranges of body fatness. There is strong evidence that altered adipose tissue function plays a crucial role in the pathogenesis of obesity-related insulin resistance and type 2 diabetes, as has recently been reviewed. Obesity is linked to respiratory diseases such as obstructive sleep apnea syndrome and obesity hypoventilation syndrome and accumulating evidence suggests an association between obesity and asthma. A potential link between obesity and COPD is also increasingly recognized although little data is known about the mechanisms underlying this association. The inflammatory and metabolic profile differs between obese with COPD and normo or underweight with COPD in part due to dysfunction of adipose tissue.

Complicated sigmoid diverticulitis.

In medical practice, the colonic diverticulitis diagnosis is easy, based especially on a barium enema and an inferior digestive endoscopy, but the diverticulitis complications, especially metastatic infections, raise serious positive and differential diagnosis problems. We present the case of a 51 year old male who comes with hepatomegaly and multiple hepatic formations, in deteriorating clinical condition, context suggestive of secondary metastasis, but after investigation it was demonstrated they were of infectious nature, from a sigmoidian diverticulitic abscess. In this case, the hepatic biopsy was appropriate and it represented an important moment in the management of the patient.

Vibroarthrography--a possible functional non-invasive method for early detection damaged cartilage joint.

The vibroacoustic signals emitted by the diarthrodial articulation during a normal movement differentiates a healthy case from a pathologic one, due to alteration in forms and contact surfaces. The differences are shown by a various dynamics of the vibroacoustic spectra. Parametric representation of the acquired signals, filtering and clinical interpretation of those allow classification and fast recognition of a normal/pathologic status of the investigated articulation by the physician. Our method of acquiring the sound and vibration signals is effectuated completely non-invasive, with a set of translators using Pulse - sounds and vibrations analyzers (a matrix of prepolarised microphones with measurement domain in infrasound scale and piezoelectric acceleration transducers). A comparative study of vibroacoustic and thermal spectra, with early alterations revealed by knee nuclear magnetic resonance, correlates vibroacoustic and thermic spectra alterations with morphological ones, by determining certain limits between normal and pathological morphofunctional patterns. This prospective comparative study will help us evaluate the method in terms of sensibility, specificity, negative and positive predictive value, indices that assure the diagnostic power to the method.

Hypertension in obese patients: a dysmetabolic hypertension with a possible adipocyte dysfunction mechanism.

Large longitudinal studies showed the epidemiological link between obesity and hypertension. During last years, multiple possible mechanisms involved in this association were identified. Adipose tissue has an important role in the genesis of hypertension in obese patients through several pathways: insulin resistance, leptin, renin-angiotensin-aldosteron system and mediators of inflammation (TNF-alpha, IL-6). Adipocyte may be the major player in the development of insulin resistance and hypertension, elements of the metabolic syndrome, responsible for the cardiovascular complications.

Relationship between serum gamma-glutamyl transferase and pulse pressure in apparently healthy middle-aged subjects.

UNLABELLED: Higher values of pulse pressure (PP)--the difference between systolic blood pressure (SBP) and diastolic blood pressure (DBP)--are associated with an increased cardiovascular risk; SBP and DBP values are correlated with serum levels of gamma-glutamyl transferase (GGT), both in drinkers and non-drinkers subjects. Moreover, some studies showed that high levels of serum GGT might be related with an increased cardiovascular risk. However, few studies analyzed the relationship between GGT and PP. In 72 subjects (18 male; 54 women), middle-aged (mean age: 36.63 yrs; limits: 24-54 yrs), apparently healthy, we performed the measurements of: weight, height (from which we calculated the body mass index [BMI]), SBP, DBP, PP, standard biochemical workup, including GGT (UI/l). RESULTS: PP values are correlated with SBP (r=0.74, p<0.001), but not with DBP (r=0.15, p=NS) values. GGT is significantly correlated with SBP (r=0.28, p=0.01), DBP (r=0.29, p=0.01), and BMI (r=0.41, p<0.001). Mean values of PP are significantly higher in those with a GGT>20 than those with GGT<20 (48.69 vs. 43.85 mmHg, p<0.05); similarly, mean values of SBP (131.66 vs. 116.81 mmHg, p=0.0004) and DBP (82.59 vs. 73.52 mmHg, p=0.0008) are higher in the group with GGT>20. We observed an ascending trend of the mean value of GGT in the different groups of PP; therefore, mean value of GGT was 19.21, 22.65, 23.18 in the PP<40, PP=40-60, respectively PP>60 groups. However, the correlation between PP and GGT was not significant, both in univariate analysis (r=0.14, p=NS) and after adjusting for SBP, DBP, BMI (r=0.12, p=NS). When we analyzed subgroups, the relationship between GGT and PP was more evident in women and in subjects with increased values of BMI. CONCLUSIONS: GGT values are significantly correlated with SBP and DBP, but not with PP, in middle-aged, apparently healthy subjects; even though the highest values of GGT are associated with an increased PP value, further studies would be necessary in order to explain this link.

Pulse pressure and inflammatory markers in apparently healthy premenopausal women.

Several epidemiological studies showed that pulse pressure (PP), as a marker of large arterial stiffness, is an independent predictor of cardiovascular risk. A high pulse pressure may induce lesions of the vessel walls and of the endothelium of the large arteries. Now, inflammation represents one of the most extensively studied pathways involved in the pathogenesis of cardiovascular disease. The aim of the present study was to evaluate if usual markers of systemic inflammation were correlated with pulse pressure. In fifty-four apparently healthy premenopausal women, without any known disease, we performed anthropometrical and blood chemistry measurements, together with the standard measurements of blood pressure. Mean values of fibrinogen are significantly more elevated in PP > 50 mmHg group than in PP < 50 mmHg group (364.79 +/- 71.07 vs. 329.31 +/- 57.81, P < 0.05). Fibrinogen was also significantly correlated with PP (r = 0.27, P < 0.05). However, after controlling for age the correlation between PP and fibrinogen was not significant (r = 0.18, P = NS). ESR was significantly correlated with PP (r = 0.31, P < 0.05) and systolic blood pressure (SBP) (r = 0.32, P < 0.05) but not with diastolic blood pressure (DBP). After controlling for age the correlation between PP and erythrocyte sedimentation rate (ESR) was not significant (r = 0.20, P = NS), but after controlling for body mass index (BMI) this correlation became significant (r = 0.28, P < 0.05). White blood cell (WBC) was not correlated with age, SBP, DBP, PP, age and BMI and the mean values of WBC were increased in the PP > 50 mmHg group, but not significantly (6637.93 +/- 1615.19 vs. 6416.67 +/- 1427.57, P = NS). In our study we found that ERS and fibrinogen values are related to pulse pressure values. Otherwise, blood pressure values, including pulse pressure, were correlated with the age of the subjects and the correlation between pulse pressure and inflammatory markers (ESR and fibrinogen) was not significant after controlling for age. After controlling for BMI, the correlation between ESR and PP remains significant.