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101.
Zaccaria Ricci Roberta Haiberger Lorenzo Tofani Stefano Romagnoli Isabella Favia Paola Cogo 《Artificial organs》2015,39(7):584-590
Multisite near infrared spectroscopy (NIRS) monitoring during pediatric cardiopulmonary bypass (CPB) has not been extensively validated. Although it might be rational to explore regional tissue saturation at different body sites (namely brain, kidney, upper body, lower body), conflicting results are currently provided by experience in children. The aim of our study was to evaluate absolute values of multisite NIRS saturation during CPB in a cohort of infants undergoing pediatric cardiac surgery to describe average differences between cerebral, renal, upper body (arm), and lower body (thigh) regional saturation. Furthermore, the correlation between cerebral NIRS and cardiac index (CI) at CPB weaning was evaluated. Twenty‐five infants were enrolled: their median weight, age, and body surface area were 3.9 (3.3–6) kg, 111 (47–203) days, and 0.24 (0.22–0.33) m2, respectively. Median Aristotle score was 8 (6–10), and vasoactive inotropic score at CPB weaning was 16 (14–25). A total of 17 430 data points were recorded by each sensor: two‐way ANOVA showed that time (P < 0.0001) and site (P = 0.0001) significantly affected variations of NIRS values: however, if cerebral NIRS values are excluded, sensor site is no more significant (P = 0.184 in the no circulatory arrest [noCA] group and P = 0.42 in the circulatory arrest [CA] group). Analysis of NIRS saturation changes over time showed that, at all sites, average NIRS values increased after CPB start, even if the increase of cerebral saturation was less intense than other sites (P < 0.0001). Detailed analysis of interaction between site of NIRS measurement and time point showed that cerebral NIRS (ranging from 65 to 75%) was always significantly lower than that of other channels (P < 0.0001) that tended to be in the range of oversaturation (80–90%), especially during the CPB phase. Average cerebral NIRS values of patients who did not undergo circulatory arrest (CA) during CPB, 10 min after CPB weaning, were associated with average CI values with a significant correlation (r = 0.7, P = 0.003). In conclusion, during CPB, cerebral NIRS values are expected to remain constantly lower than somatic sensors, which instead tend to show similar elevated saturations, regardless of their position. Based on these results, positioning of noncerebral NIRS sensors during CPB without CA may be questioned. 相似文献
102.
Roy RS Karle IL Raghothama S Balaram P 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(47):16478-16482
Conformational studies on the synthetic 11-aa peptide t-butoxycarbonyl (Boc)-Val-Ala-Phe-alpha-aminoisobutyric acid (Aib)-(R)-beta3-homovaline (betaVal)-(S)-beta3-homophenylalanine (betaPhe)-Aib-Val-Ala-Phe-Aib-methyl ester (OMe) (peptide 1; betaVal and betaPhe are beta amino acids generated by homologation of the corresponding l-residues) establish that insertion of two consecutive beta residues into a polypeptide helix can be accomplished without significant structural distortion. Crystal-structure analysis reveals a continuous helical conformation encompassing the segment of residues 2-10 of peptide 1. At the site of insertion of the betabeta segment, helical hydrogen-bonded rings are expanded. A C15 hydrogen bond for the alphabetabeta segment and two C14 hydrogen bonds for the alphaalphabeta or betaalphaalpha segments have been characterized. The following conformational angles were determined from the crystal structure for the beta residues: betaVal-5 (= -126 degrees, = 76 degrees, and psi = -124) and betaPhe-6 (=-88 degrees, = 80 degrees, and psi =-118). The N terminus of the peptide is partially unfolded in crystals. The 500-MHz 1H-NMR studies establish a continuous helix over the entire length of the peptide in CDCl3 solution, as evidenced by diagnostic nuclear Overhauser effects. The presence of seven intramolecular hydrogen bonds is also established by using solvent dependence of NH chemical shifts. 相似文献
103.
Shangyuan Feng Wenbo Wang Isabella T. Tai Guannan Chen Rong Chen Haishan Zeng 《Biomedical optics express》2015,6(9):3494-3502
Fecal based tests have limited diagnostic values in detecting adenomatous polyps, the precursor lesions to colorectal cancer (CRC). Surface enhanced Raman spectroscopy (SERS) using silver nanoparticles as substrate is a multiplexed analytical technique capable of detecting biomolecules with high sensitivity. This study utilizes SERS to analyze blood plasma for detecting both CRC and adenomatous polyps for the first time. Blood plasma samples are collected from healthy control subjects and patients diagnosed with adenomas and CRC. Using a real-time Raman system, SERS spectra for blood plasma samples are measured in 1 s. The collected SERS spectra are analyzed with partial least squares-discriminant analysis. Classification of normal versus CRC plus adenomatous polyps achieved diagnostic sensitivity of 86.4% and specificity of 80%. The results suggest that blood plasma SERS analysis could be a potential screening test to detect both CRC and adenomas.OCIS codes: (240.6695) Surface-enhanced Raman scattering, (170.1470) Blood or tissue constituent monitoring, (170.5660) Raman spectroscopy, (170.4580) Optical diagnostics for medicine 相似文献
104.
105.
Placental expression of soluble fms-like tyrosine kinase 1 is increased in singletons and twin pregnancies with intrauterine growth restriction 总被引:1,自引:0,他引:1
Nevo O Many A Xu J Kingdom J Piccoli E Zamudio S Post M Bocking A Todros T Caniggia I 《The Journal of clinical endocrinology and metabolism》2008,93(1):285-292
OBJECTIVE: Intrauterine growth restriction (IUGR) is characterized by decreased placental perfusion. Low oxygen has been shown to increase soluble fms-like tyrosine kinase 1 (sFlt-1) expression in the human placenta. The objective of this study was to examine sFlt-1 expression in different types of IUGR pregnancies, including early-onset severe cases characterized by abnormal umbilical and uterine artery Doppler and discordant IUGR twins in which the normal cotwin represents the optimal control because both placentas share the same uterine environment. PATIENTS: Placentas from four subgroups were collected: early severe IUGR with umbilical artery absent end diastolic flow (n = 19), small for gestational age with normal uterine and umbilical artery Doppler (n = 11), severely growth-restricted dichorionic and monochorionic twins with abnormal umbilical artery Doppler (n = 9), preeclamptic twins (n = 3), and age-matched normal singletons (n = 19) and twin controls (n = 8). RESULTS: Expression of sFlt-1 mRNA and protein was significantly increased in IUGR placentas compared with small for gestational age and normal control placentas. sFlt-1 expression levels were also significantly greater in the small IUGR twin placentas from discordant twin pregnancies compared with the normal cotwin. In preeclamptic twins, sFlt-1 expression was increased in only one of the two placentas. CONCLUSIONS: Our results demonstrate that sFlt-1 expression is increased in severe IUGR placentas with abnormal umbilical artery Doppler of singletons and also in discordant IUGR twins. Reduced placental perfusion may contribute to the increased expression of sFlt-1 in IUGR pregnancies. Our data are compatible with differential sFlt-1 expression in placentas from discordant twins. 相似文献
106.
Mechanism of luminal patency of the self‐expanding sideguard sidebranch stent: Evaluation by intravascular ultrasound and optical coherence tomography
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107.
Tiziana Bachetti Isabella Ceccherini 《Journal of molecular medicine (Berlin, Germany)》2014,92(6):583-594
Autophagy prevents cellular damage by eliminating insoluble aggregates of mutant misfolded proteins, which accumulate under different pathological conditions. Downregulation of autophagy enhances the inflammatory response and thus represents a possible common pathogenic event underlying a number of autoinflammatory syndromes, such as tumor necrosis factor (TNF) receptor-associated periodic syndrome (TRAPS). The pathogenesis of other monogenic or complex disorders that display symptoms of excessive inflammation also involve the autophagy pathway. Studies have shown that TRAPS-associated TNFRSF1A mutations induce cytoplasmic retention of the TNFR1 receptor, defective TNF-induced apoptosis, and production of reactive oxygen species (ROS). Furthermore, autophagy impairment may account for the pathogenic effects of TNFRSF1A mutations, thus inducing inflammation in TRAPS. In this review, we summarize the molecular interactions and functional links between autophagy with regard to nuclear factor-kappa B activation, ROS production, and apoptosis. Furthermore, we propose a complex interplay of these pathways as a model to explain the relationship between mutant protein misfolding and inflammation in genetically determined and aggregation-prone diseases. Accordingly, autophagy function should be investigated in all diseases showing an inflammatory component, and for which the molecular pathogenesis is still unclear. 相似文献
108.
Roberto Gasparini Maurizio Comanducci Daniela Amicizia Filippo Ansaldi Paola Canepa Andrea Orsi Giancarlo Icardi Emanuela Rizzitelli Gabriella De Angelis Stefania Bambini Monica Moschioni Sara Comandi Isabella Simmini Giueseppe Boccadifuoco Brunella Brunelli Marzia Monica Giuliani Mariagrazia Pizza Donatella Panatto 《Journal of clinical microbiology》2014,52(6):1901-1910
Neisseria meningitidis is an obligate human commensal that commonly colonizes the oropharyngeal mucosa. Carriage is age dependent and very common in young adults. The relationships between carriage and invasive disease are not completely understood. In this work, we performed a longitudinal carrier study in adolescents and young adults (173 subjects). Overall, 32 subjects (18.5%) had results that were positive for meningococcal carriage in at least one visit (average monthly carriage rate, 12.1%). Only five subjects tested positive at all four visits. All meningococcal isolates were characterized by molecular and serological techniques. Multilocus sequence typing, PorA typing, and sequencing of the 4CMenB vaccine antigens were used to assess strain diversity. The majority of positive subjects were colonized by capsule null (34.4%) and capsular group B strains (28.1%), accounting for 23.5% and 29.4% of the total number of isolates, respectively. The fHbp and nhba genes were present in all isolates, while the nadA gene was present in 5% of the isolates. The genetic variability of the 4CMenB vaccine antigens in this collection was relatively high compared with that of other disease-causing strain panels. Indications about the persistence of the carriage state were limited to the time span of the study. All strains isolated from the same subject were identical or cumulated minor changes over time. The expression levels and antigenicities of the 4CMenB vaccine antigens in each strain were analyzed by the meningococcal antigen typing system (MATS), which revealed that expression can change over time in the same individual. Future analysis of antigen variability and expression in carrier strains after the introduction of the MenB vaccine will allow for a definition of its impact on nasopharyngeal/oropharyngeal carriage. 相似文献
109.
Laura Annaratone Enzo Medico Nelson Rangel Isabella Castellano Caterina Marchiò Anna Sapino Gianni Bussolati 《Endocrine pathology》2014,25(3):219-228
Discordant data are reported in the literature on the definition, incidence and clinical features of neuroendocrine (NE) carcinomas of the breast. This tumour entity is currently assessed by immunohistochemistry (IHC) detecting “general” NE markers such as chromogranin A (CHGA) and synaptophysin (SYP), but other markers have been considered as well. In the present study, in addition to CHGA and SYP, we investigated the expression of VGF, a neurotrophin-inducible gene, which is emerging as a new specific NE marker. In order to evaluate the differential expression of these neuro-endocrine markers in breast cancers, we conducted parallel immunohistochemical and gene expression analyses, using PCR, gene array and real-time quantitative PCR procedures. Data obtained in 28 cases were further validated with a meta-analysis of published datasets of 103 breast cancer cases. The value of IHC positivity (irrespective of the percentage of positive cells) was confirmed by over-expression of the related gene. However, the genetic approach emerged as more sensitive, showing over-expression of NE markers in a subset of IHC-negative carcinomas. In conclusion, the present study confirms, by a novel approach, the occurrence of NE differentiation in breast cancers. Over-expression of one or more NE marker (CHGA and/or SYP and/or VGF) characterizes a significant fraction (approximately 10 %) of infiltrative breast cancers. 相似文献
110.
Stefano?NardiniEmail author Isabella?Annesi-Maesano Mario?Del?Donno Maurizio?Delucchi Germano?Bettoncelli Vincenzo?Lamberti Carlo?Patera Mario?Polverino Antonio?Russo Carlo?Santoriello Patrizio?Soverina 《Multidisciplinary respiratory medicine》2014,9(1):46
Respiratory diseases in Italy already now represent an emergency (they are the 3rd ranking cause of death in the world, and the 2nd if Lung cancer is included). In countries similar to our own, they result as the principal cause for a visit to the general practitioner (GP) and the second main cause after injury for recourse to Emergency Care. Their frequency is probably higher than estimated (given that respiratory diseases are currently underdiagnosed). The trend is towards a further increase due to epidemiologic and demographic factors (foremost amongst which are the widespread diffusion of cigarette smoking, the increasing mean age of the general population, immigration, and pollution). Within the more general problem of chronic disease care, chronic respiratory diseases (CRDs) constitute one of the four national priorities in that they represent an important burden for society in terms of mortality, invalidity, and direct healthcare costs. The strategy suggested by the World Health Organization (WHO) is an integrated approach consisting of three goals: inform about health, reduce risk exposure, improve patient care. The three goals are translated into practice in the three areas of prevention (1-primary, 2-secondary, 3-tertiary) as: 1) actions of primary (universal) prevention targeted at the general population with the aim to control the causes of disease, and actions of Predictive Medicine - again addressing the general population but aimed at measuring the individual’s risk for disease insurgence; 2) actions of early diagnosis targeted at groups or - more precisely - subgroups identified as at risk; 3) continuous improvement and integration of care and rehabilitation support - destined at the greatest possible number of patients, at all stages of disease severity. In Italy, COPD care is generally still inadequate. Existing guidelines, institutional and non-institutional, are inadequately implemented: the international guidelines are not always adaptable to the Italian context; the document of the Agency for Regional Healthcare Services (AGE.NA.S) is a more suited compendium for consultation, and the recent joint statement on integrated COPD management of the three major Italian scientific Associations in the respiratory area together with the contribution of a Society of General Medicine deals prevalently with some critical issues (appropriateness of diagnosis, pharmacological treatment, rehabilitation, continuing care); also the document “Care Continuity: Chronic Obstructive Pulmonary Disease (COPD)” of the Global Alliance against chronic Respiratory Diseases (GARD)-Italy does not treat in depth the issue of early diagnosis. The present document – produced by the AIMAR (Interdisciplinary Association for Research in Lung Disease) Task Force for early diagnosis of chronic respiratory disease based on the WHO/GARD model and on available evidence and expertise –after a general examination of the main epidemiologic aspects, proposes to integrate the above-mentioned existing documents. In particular: a) it formally indicates on the basis of the available evidence the modalities and the instruments necessary for carrying out secondary prevention at the primary care level (a pro-active,‘case-finding’approach; assessment of the individual’s level of risk of COPD; use of short questionnaires for an initial screening based on symptoms; use of simple spirometry for the second level of screening); b) it identifies possible ways of including these activities within primary care practice; c) it places early diagnosis within the “systemic”, consequential management of chronic respiratory diseases, which will be briefly described with the aid of schemes taken from the Italian and international reference documents. 相似文献