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C Barbieri

Publications and source records attributed to C Barbieri.

At least 19 recordsLinked to original sources
PubMed2006

Overcoming the rayleigh criterion limit with optical vortices.

We experimentally and numerically tested the separability of two independent equally luminous monochromatic and white light sources at the diffraction limit, using optical vortices (OV). The diffraction pattern of one of the two sources crosses a fork hologram on its center generating the Laguerre-Gaussian (LG) transform of an Airy disk. The second source, crossing the fork hologram in positions different from the optical center, generates nonsymmetric LG patterns. We formulated a criterion, based on the asymmetric intensity distribution of the superposed LG patterns so created, to resolve the two sources at angular distances much below the Rayleigh criterion. Analogous experiments in white light allow angular resolutions which are still one order of magnitude below the Rayleigh criterion. The use of OVs might offer new applications for stellar separation in future space experiments.

Journal Article↗
PubMed2004

Cytokine and chemokine levels in systemic sclerosis: relationship with cutaneous and internal organ involvement.

Systemic sclerosis (SSc) is a connective tissue disorder characterized by excessive collagen deposition in the skin and internal organs. Several cytokines and chemokines have been implicated in the induction of fibrosis, but a definitive relationship between specific cytokines and organ involvement has not been established yet. Serum samples, PBMC and T cell lines (TCL) obtained from 54 patients affected by SSc and 20 healthy donors (HD) were examined by ELISA for Interferon-gamma (IFN-gamma ), interleukin (IL)-4, IL-6, IL-10, IL-18, Transforming growth factor (TGF)-beta1, Tumour necrosis factor (TNF)-alpha, sCD30, Macrophage derived chemokine (MDC), Monocyte chemoattractant protein (MCP)-1, Macrophage inflammatory protein (MIP)-1alpha and Regulated on activation normal T-cell expressed and secreted (RANTES). In all the SSc serum samples, we found significantly increased levels of IL6, TNFalpha and MCP-1 but reduced amounts of gamma-IFN and MDC. IL6, IL10, IL18, MIP-1alpha and TNFalpha measured in supernatants from PHA-stimulated PBMC and IL6, MCP-1 and RANTES in supernatants from stimulated TCL were also increased in patients. MDC was decreased in all the biological SSc sources studied. TGF-beta1, IL10, and sCD30 were produced at a significantly lower level by SSc TCL. Serum IL6 and sCD30 levels were significantly increased in dc-SSc patients compared to lc-SSc as were levels of MCP-1 produced by PBMC and IL10 from TCL. We observed a strict relationship between pulmonary fibrosis and IL10, MCP-1 (both from TCL) and serum IL6. Kidney involvement was related to serum MCP-1 levels and IL18 production from PBMC. Oesophageal involvement correlated with MDC production from PBMC and IL10 synthesis by TCL. We showed that IL-6, IL-10, MDC and MCP-1 are variably associated with internal organ involvement and allow the discrimination between limited and diffuse forms of the disease.

Cell Line↗
PubMed2003

Effect of surgical treatment on the cellular immune response of gastric cancer patients.

Patients with gastric cancer have a variety of immunological abnormalities. In the present study the lymphocytes and their subsets were determined in the peripheral blood of patients with gastric cancer (N = 41) both before and after surgical treatment. The percent of helper/inducer CD4 T cells (43.6 +/- 8.9) was not different after tumor resection (43.6 +/- 8.2). The percent of the cytotoxic CD8+ T cell population decreased significantly, whether patients were treated surgically (27.2 +/- 5.8%, N = 20) or not (27.3 +/- 7.3%, N = 20) compared to individuals with inflammatory disease (30.9 +/- 7.5%) or to healthy individuals (33.2 +/- 7.6%). The CD4/CD8 ratio consequently increased in the group of cancer patients. The peripheral blood lymphocytes of gastric cancer patients showed reduced responsiveness to mitogens. The defective blastogenic response of the lymphocytes was not associated with the production of transforming growth factor beta (TGF- ) since the patients with cancer had reduced production of TGF- Beta1 (269 +/- 239 pg/ml, N = 20) in comparison to the normal individuals (884 +/- 175 pg/ml, N = 20). These results indicate that the immune response of gastric cancer patients was not significantly modified by surgical treatment when evaluated four weeks after surgery and that the immunosuppression observed was not due to an increase in TGF- 1 production by peripheral leukocytes.

Adult↗
PubMed2002

True 3D reconstruction for planning of surgery on malformed skulls.

OBJECTIVES: Since the difficulty associated with surgical planning of craniosynostosis is mostly due to the inadequate possibilities for simulation of surgery, a new technique for constructing a precise reproduction of a patient's malformed skull has been developed. MATERIALS AND METHODS: CT scans of ten malformed skulls on a scale of 1:1 and with 1-mm slices have been used to reconstruct the skulls in a special resin using a special lathe used in the automobile construction industry for formula one engines. This lathe works in the opposite way to other lathes: by apposition of material instead of subtraction. RESULTS: The anatomical detail of the phantom is of a very high degree. The surgical planning it allows has proved highly consistent with reality in all cases in which it has been used in the planning before the operation. DISCUSSION AND CONCLUSIONS: This technique has made it possible to plan the surgical treatment of all patients with craniosynostosis in a highly satisfactory way. It has reduced operating times, in addition to which it provides information on materials needed, avoiding waste, and is also an excellent teaching method for residents.

Craniosynostoses↗
PubMed2001

Telomeric associations and chromosome instability in ataxia telangiectasia T cells characterized by TCL1 expression.

T-cell tumors in ataxia telangiectasia (AT), such as T-PLL/T-CLL, are first preceded by the development of a large clone of T-lymphocytes, characterized by chromosomal rearrangements, which usually involve specific regions such as the 14q11 region. Malignancy develops years later, after additional chromosomal changes resulting from the genomic instability consequent to ATM disruption and to the activation of the TCL1 oncogene. Here we report the results of a cytogenetic follow-up of an AT patient (AT94-1), still without signs of hematological abnormalities, bearing a T-lymphocyte clone characterized by the t(14;14)(q11;q32) rearrangement and having TCL1 expression. We demonstrated that in clonal cells TCL1 expression correlates with increasing genomic instability and in time this mainly induces chromosomal rearrangements and telomeric associations (tas). Chromosome 21 is not randomly involved; in particular, an i(21q) indicates that it is a subclone prone to additional genetic changes and could represent an early chromosomal rearrangement involved in tumorigenesis. With regard to the increase in tas, we observed that: (i) it is inversely correlated with the proliferative ability of AT94-1 lymphocytes in PHA-stimulated short-term cultures (cell aging in vitro); (ii) this increase is not due to changes either in cell radiosensitivity (measured as bleomycin (BML)-sensitivity) or due to an illegitimate recombination (measured as adriamycin-sensitivity), which may not be sufficient for tumor development.

Adult↗
PubMed2000

Scanning laser polarimetry measurements after laser-assisted in situ keratomileusis.

PURPOSE: To evaluate the effect of laser-assisted in situ keratomileusis on retinal nerve fiber layer thickness measurements obtained with scanning laser polarimetry. METHODS: Thirteen consecutive eyes (13 patients) undergoing laser-assisted in situ keratomileusis were enrolled in this prospective study. Scanning laser polarimetry (NFA-GDx; Laser Diagnostic Technologies, Inc, San Diego, California) examination was performed 1 week before and 1 to 8 weeks after laser-assisted in situ keratomileusis surgery. Intraocular pressure was normal at all preoperative and postoperative examinations. Total mean, and superior, temporal, inferior, and nasal mean retinal nerve fiber layer thickness values before and after laser-assisted in situ keratomileusis were compared by Student paired t test. RESULTS: Mean +/- SD patient age was 34.6 +/- 10.9 years (range, 20 to 56 years). Mean +/- SD preoperative spherical equivalent refractive error was -6.6 +/- 3.1 diopters (range, -3.25 to -13.25 diopters) and mean +/- SD spherical equivalent refractive surgical correction was -6.2 +/- 3.0 diopters (range, -2.9 to -12.25 diopters). Total mean retinal nerve fiber layer and superior, inferior, temporal, and nasal mean retinal nerve fiber layer thicknesses were thinner after laser-assisted in situ keratomileusis (P =.01, for all comparisons, paired t test). CONCLUSIONS: Measurements of the retinal nerve fiber layer with scanning laser polarimetry depend on a corneal compensator inherent in the device. Keratorefractive surgery may affect scanning laser polarimetry measurements.

Adult↗
PubMed2000

Pleural fluid pH as a predictor of survival for patients with malignant pleural effusions.

STUDY OBJECTIVES: To assess the accuracy of pleural fluid (PF) pH in predicting duration of survival of patients with malignant pleural effusions. DESIGN: Analysis of patient-level data from nine sources retrieved from a MEDLINE search and correspondence with primary investigators. STUDY SELECTION: Published and unpublished studies that report PF pH values and duration of survival of patients with malignant pleural effusions. DATA COLLECTION AND ANALYSIS: Primary investigators supplied patient-level data (n = 417), which was examined by receiver operating characteristic (ROC) analysis, logistic regression, and survival time modeling to determine the utility of PF pH for predicting survival compared with other clinical factors. The primary investigations were graded for study design. MEASUREMENTS AND RESULTS: Median survival (n = 417) was 4.0 months: PF pH (p < 0.0039) was an independent predictor of survival duration. A PF pH test threshold < or = 7.28 had the highest accuracy for identifying poor 1-, 2-, and 3-month survivals. The predictive accuracies of PF pH (area under the ROC curve range, 0.571 to 0.662) and a PF pH-high-risk tumor (lung, soft tissues, renal, ovary, gastrointestinal, prostate, and oropharynx) model (odds ratio range, 2.91 to 6.67), however, were modest for predicting 1-, 2-, and 3-month survival. Only 54.4% and 62.7% of patients identified by PF pH < or = 7.28 or the PF pH-high-risk tumor model to die within 3 months were correctly classified. Weaknesses of the primary data were identified. CONCLUSIONS: PF pH has insufficient predictive accuracy for selecting patients for pleurodesis on the basis of estimated survival.

Body Fluids↗
PubMed2000

Pleural fluid pH as a predictor of pleurodesis failure: analysis of primary data.

STUDY OBJECTIVES: To determine the predictive accuracy of pH for identifying patients with malignant pleural effusions who will fail pleurodesis. DESIGN: Analysis of published and unpublished individual patient-level data retrieved from a MEDLINE search and correspondence with primary investigators. STUDY SELECTION: Studies that reported pleural fluid pH values and outcomes of pleurodesis for patients with malignant pleural effusions. DATA COLLECTION AND ANALYSIS: Primary investigators supplied data for 433 patients. Receiver operating characteristic analysis and logistic regression estimated the predictive accuracy, decision thresholds, and value of pleural fluid pH compared with other clinical factors. The primary investigations were graded for study design. RESULTS: Pleural fluid pH was the only independent predictor of pleurodesis failure (odds ratio, 4.46; 95% confidence interval [CI], 2.69 to 7.45; p < 0.0001) and had an area under the receiver operating characteristic curve (decision threshold, < or = 7.28) of 0.671 (95% CI, 0.624 to 0.715). The pH model fit the data well (p = 0.48) with the probability of pleurodesis failure increasing as pH decreased; specificity and negative predictive values for pleurodesis failure exceeded 90% and 80%, respectively, with a positive predictive value of 45.7% at pH values < or = 7.15. The primary studies had several important design limitations. CONCLUSIONS: Using patient-level data, this study showed that pleural fluid pH has only modest predictive value for predicting symptomatic failure and should be used with caution, if at all, in selecting patients for pleurodesis. The limitations of the primary studies and low predictive accuracy should be considered when using pleural fluid pH for patient care.

Aged↗
PubMed2000

End-of-life care preferences of patients enrolled in cardiovascular rehabilitation programs.

STUDY OBJECTIVES: The study assessed the interests of ambulatory cardiac patients in advance planning and their willingness to participate in rehabilitation program-based end-of-life education. DESIGN: Observational survey study. SETTING: Fourteen outpatient cardiac rehabilitation programs in 11 states. PARTICIPANTS: Four hundred fifteen subjects enrolled in cardiac rehabilitation. MEASUREMENTS AND RESULTS: A questionnaire determined patient preferences for advance planning, completion of advance directives, completion of patient-physician discussions on end-of-life care, and effects of health status on patient acceptance of life-sustaining interventions. Seventy-two percent of patients wanted to direct their own end-of-life care, 86% desired more information on advance directives, 62% wanted to learn about life-sustaining care, and 96% were receptive to advance-planning discussions with their physicians. Seventy-two percent of patients had considered that they might require life-sustaining care in the future; acceptability of resuscitative care depended on health status and probability of survival. However, only 15% had discussed advance planning with their physicians, and 10% were confident that their physicians understood their end-of-life wishes. Physicians and cardiovascular rehabilitation programs were considered desirable sources of information on advance planning. CONCLUSIONS: Cardiac patients enrolled in rehabilitation programs want to learn more about end-of-life care and need more opportunities to discuss advance planning with their physicians. Patients consider cardiovascular rehabilitation programs to be acceptable sites for advance planning education.

Advance Directives↗
PubMed1999

Hydroa vacciniforme persistent in a 60-year-old man.

Hydroa vacciniforme (HV) is an idiopathic photodermatosis with onset in childhood, a chronic-recurrent course, and spontaneous resolution in adolescence or early adulthood. We present a patient with typical HV in whom lesions began in childhood and continued until 60 years of age.

Chronic Disease↗
PubMed1998

Compliance with do-not-resuscitate orders for hospitalized patients transported to radiology departments.

BACKGROUND: Little is known about the effectiveness of do-not-resuscitate (DNR) orders during transport of hospitalized patients away from their rooms. OBJECTIVE: To determine compliance with DNR orders in radiology departments. DESIGN: Observational study. SETTING: 248 hospital-based radiology departments. PARTICIPANTS: 248 radiology department representatives. MEASUREMENTS: 10-item questionnaire examining the response of radiology personnel to patients with DNR orders who experience cardiopulmonary arrest. RESULTS: Written DNR protocols and structured procedures for communicating DNR status were used by 18.5% (CI, 13.7% to 23.4%) and 18.1% (CI, 13.3% to 23.0%) of departments, respectively. Medical chart review was the only source of information on DNR status for 41.5% (CI, 35.4% to 47.7%) of departments. It was found that 20.2% of respondents (CI, 15.2% to 25.2%) would resuscitate patients with DNR orders and that 38.3% (CI, 32.3% to 44.4%) had resuscitated patients with DNR orders in the past. CONCLUSIONS: Most radiology departments do not have formal procedures to prevent patients from undergoing unwanted or inappropriate resuscitative interventions, and DNR orders are frequently overruled.

Advance Directive Adherence↗
PubMed1998

Communicating do-not-resuscitate orders with a computer-based system.

BACKGROUND: Do-not-resuscitate (DNR) orders for critically ill patients are frequently miscommunicated between attending physicians, house staff, and nurses. A computer-based system was developed to improve the communication of a procedure-specific DNR order form. METHODS: Concordance of understanding of patients' DNR status was measured with the use of unstructured DNR orders (period 1), procedure-specific DNR order forms (period 2), and procedure-specific DNR order forms administered with a computer-based communication system (period 3). The 3 components of the DNR order assessed were (1) the clinical events to which the DNR order applied, (2) whether the DNR order withheld all elements of cardiopulmonary resuscitation, and (3) whether other treatments were to be withheld. RESULTS: For the 147 patients, the computer-based system in period 3 (n = 71) improved concordance for attending physicians and nurses or residents for all 3 of the DNR components compared with period 1 (n = 40) and some of the DNR components compared with period 2 (n = 36). Concordance was "substantial" or "almost perfect" as measured by the K statistic during period 3. The proportion of agreement for the composite of all 3 components of the DNR order increased during each period (P<.001, period 3 vs period 1). Overall agreement between all caregivers for the composite DNR order also improved from period 1 (22.2%) to period 2 (47.8%) and period 3 (61.9%; P<.001 vs period 1). Errors in order entry were detected by physicians because of the computer system and corrected in 9.9% of DNR orders in period 3. Progress note documentation of DNR status did not improve during period 3. The procedures of period 3 were considered acceptable by the physician and nursing staff. CONCLUSION: A computer-based system combined with a procedure-specific DNR order form improves communication of patients' DNR status in a critical care setting.

Adult↗
PubMed1998

99mTc SESTAMIBI scintigraphic evaluation of skeletal muscle disease in patients with systemic sclerosis: diagnostic reliability and comparison with cardiac function and perfusion.

The diagnosis of skeletal muscle involvement in patients with systemic sclerosis (SSc) is usually based on clinical, laboratory, electromyographic, and bioptic evidence of muscle disorder, whereas SSc cardiac disease is well established by nuclear medicine techniques (radionuclide ventriculography and myocardial scintigraphy). Previous reports have retrospectively hypothesized a possible relationship between cardiac and muscle involvement in scleroderma patients. In order to improve overall diagnostic accuracy in the qualitative/quantitative assessment of skeletal muscle involvement in these patients and to compare these results with those obtained at the cardiac level, diethylenetriaminepentaacetic acid (DTPA)-99mTc radionuclide ventriculography and 99mTc SESTAMIBI myocardial and muscular scintigraphic examinations were performed in 10 SSc patients and in five healthy subjects. Muscular radioactivity, as assessed at thigh and calf levels by means of a segmental score, was significantly decreased in SSc patients in comparison with healthy subjects (global score value 15.6+/-2.2 vs 22.7+/-1.6, p<0.001), as well as right ventricular ejection fraction (RVEF, 34.3%+/-5.3 vs 53.6%+/-4.2, p<0.001) and myocardial segmental perfusion (global score value, 19.6+/-2 vs 25.9+/-1.1, p<0.01). The results show a high frequency of skeletal muscle involvement in patients with SSc. Moreover, scleroderma patients with muscle disorders, as evidenced by scintigraphy, show a comparable occurrence of cardiac involvement, even in the absence of clinical signs of cardiac dysfunction.

Cardiomyopathies↗
PubMed1998

Methodologic standards for diagnostic test research in pulmonary medicine.

STUDY OBJECTIVES: To determine conformance with methodologic standards in the evaluation of diagnostic tests. DATA SOURCES: MEDLINE database search (1992 to 1997) of nine prominent general medicine and six subspecialty journals for articles that report discriminative properties of diagnostic tests in pulmonary medicine. STUDY SELECTION: Articles were eligible if they reported discriminative properties of diagnostic tests in humans, diagnostic tests were intended for the detection of existing conditions, and the target disorder was relevant to pulmonary medicine. DATA EXTRACTION: Each study was critically reviewed independently by two observers. DATA SYNTHESIS: Of the 1,029 retrieved articles, 41 met study inclusion criteria. The median number of the 12 major standards for design fulfilled by study articles was 6 (range, 1 to 12, 25th to 75th percentile, 5.0 to 8.5) and only 2 articles fulfilled all 12 standards. Seven (17%) articles did not report any standard measures of diagnostic accuracy and 7 (17%) provided data only for sensitivity and specificity. Only 4 of 17 articles (24%) that compared different tests used standard statistical methods. CONCLUSION: These results indicate that greater methodologic rigor is needed for studies that evaluate diagnostic tests in pulmonary medicine. Existing deficiencies in methodology risk the introduction of invalid tests into clinical practice.

Area Under Curve↗
PubMed1997

Influence of stimulus salience and attentional demands on visual search patterns in hemispatial neglect.

Seventy-five left and right brain-damaged patients, with or without hemispatial neglect, and 40 age-matched control subjects were tested on cancellation tasks with two different visual textures modeled after Julesz (1981). In one condition ("preattentive"), target elements segregated easily from background elements and were perceived effortlessly. In the other ("attentive"), target elements did not segregate easily and could be detected only after prolonged focal scrutiny. Both controls and patients were more accurate and faster on the preattentive than attentive texture. However, only neglect patients were disproportionately impaired on the attentive texture, thus suggesting that unilateral neglect is exacerbated by the low visual salience of the stimuli and a higher engagement of focal attention. Thus, a simple bedside test may help to tell apart the level of visual information processing maximally impaired in neglect patients.

Analysis of Variance↗
PubMed1997

A practical device for histological fixative procedures that limits formaldehyde deleterious effects in laboratory environments.

Formaldehyde vapor levels were evaluated in a histological fixative laboratory and environments where anatomical pieces treated with this fixative are stored or handled. Formaldehyde concentration in the air may reach values up to 9 times higher than that established (0.3 ppm) by the international official surveillance bureaus. These results emphasize the need to perform these activities in an environment with good exhaust conditions in view of the deleterious effects of formaldehyde. Therefore, we designed a practical modular mechanical device to carry out transcardiac fixative perfusion inside an exhaust hood. This device is coupled to accessories that help surgical procedures, animal head tissue cooling and collection of organic and chemical residues for posterior discharge or treatment. In addition, as it was designed to be readily assembled and disassembled it releases the hood for other tasks.

Air Pollutants↗
PubMed1997

Outcomes of advance directive education of pulmonary rehabilitation patients.

We performed a two-site prospective, controlled interventional study of patients enrolled in pulmonary rehabilitation to assess effects of advance directive education on completion of (1) living wills, (2) durable powers of attorney for health care (DPAHC), (3) patient-physician discussions about advance directives, and (4) discussions about life support, in addition to (5) patient impressions that their physicians understood their end-of-life preferences. The educational group had an increase (p < 0.05) in all five study outcomes compared with baseline values; the control group had an increase in three of five outcomes. The effect strength was greater in the educational compared with the control group for completion of DPAHC (odds ratio [OR] = 3.6, 95% confidence interval [CI] 1.1 to 12.9), advance directive discussions (OR = 2.9, 95% CI 1.1 to 8.3), initiation of life-support discussions (OR = 2.7, 95% CI 1.0 to 7.7), and development of patient assurance that their physicians understand their preferences (OR = 3.7, 95% CI 1.3 to 13.4). The educational intervention was an independent explanatory factor by multivariate analysis. We conclude that patients enrolled in pulmonary rehabilitation are receptive to advance care planning, which is promoted by education on end-of-life issues.

Adult↗