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1.
Prostate Cancer Prostatic Dis ; 26(2): 374-378, 2023 06.
Article in English | MEDLINE | ID: mdl-35729328

ABSTRACT

BACKGROUND: To explore the role of preoperative MRI prostate shape in urinary incontinence after robot-assisted radical prostatectomy (RARP). METHODS: Patients were stratified into four groups based on the mpMRI prostatic apex shape: Group A (prostatic apex overlapping the membranous urethra anteriorly and posteriorly), Group B and C (overlap of the prostatic apex of the anterior or posterior membranous urethra, respectively) and Group D (no overlap). Preoperative variables and intraoperative data were compared. Continence recovery was defined as no pad/day or 1 safety pad/day by an outpatient evaluation performed at 1, 3, 6, and 12 months after RARP. RESULTS: One hundred patients underwent RARP were classified as belonging to Group A (n = 30), Group B (n = 16), Group C (n = 14), and Group D (n = 40). Group D showed a significantly more favorable urinary continence recovery after RARP respect to all the other shapes presenting any forms of overlapping (HR = 1.9, 95% CI 1.2-3.1, p = 0.007). The estimated HR remained substantially unchanged after adjusting by age, body mass index, CCI, prostate volume, and bladder neck sparing (HR = 1.9, 95% CI 1.1-3.2, p = 0.016). The continence recovery median time was 9 months for Group A + B + C (95% CI 5-11) and 4 months for Group D (95% CI 2-6) (p = 0.023). CONCLUSION: Shape D showed a better continence recovery when compared to other shapes presenting any kind of overlapping of the prostatic apex over the membranous urethra.


Subject(s)
Prostatic Neoplasms , Robotic Surgical Procedures , Robotics , Male , Humans , Prostate/diagnostic imaging , Prostate/surgery , Robotic Surgical Procedures/adverse effects , Robotic Surgical Procedures/methods , Prostatic Neoplasms/surgery , Prostatectomy/adverse effects , Prostatectomy/methods , Cohort Studies , Treatment Outcome
2.
Musculoskelet Surg ; 107(4): 385-390, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36370251

ABSTRACT

PURPOSE: To compare clinical outcomes and surgical times of two different types of total knee arthroplasty(TKA), postero-stabilized(PS) and condylar-stabilized(CS), in relation to posterior tibial slope(PTS) values and the deviation of these values from the surgical technique. METHODS: 168 patients undergoing TKA surgery between 2016 and 2020 met our inclusion criteria. For each case, gender, age at surgery, operating time, type of implant and preoperative PTS(preop-PTS) and postoperative PTS(postop-PTS) measurements were collected; difference(∆PTS) between preop-PTS and postop-PTS was also calculated. Short Form 12 Mental and Physical scores(SF-12 M and P) and functional Knee Society Score(fKSS) were collected preoperatively and at a minimum of 12 months postoperatively. Four subgroups were thus created in relation to PS or CS system and postop-PTS value(≤ 5°and > 5°). RESULTS: Of the 168 patients, 96 had a PS system and 72 CS system. Performing a CS-TKA took less time than a PS-TKA(p < 0.05). SF-12P showed better results(p < 0.05) in CS-TKA group than PS-TKA, probably because of the younger age of CS-TKA patients(p < 0.05). In the PS > 5° all examined postoperative scores were better(p < 0.05) than PS ≤ 5°, while only fKSS was better(p < 0.05) in CS > 5° than CS ≤ 5°. No significant difference(p > 0.05) in terms of postoperative outcomes between the PS > 5° and CS > 5° was noted, whereas only SF-12P was better in the CS ≤ 5° compared with PS ≤ 5°. Highest values of SF-12 M and fKSS were obtained in the PS ≤ 5°, in which postop-PTS was closer to technique. CONCLUSION: When performing a PS-TKA, the best result was obtained with a postop-PTS > 5°, but comparable outcomes between the two systems were evident with postop-PTS > 5°. It is crucial to come as close as possible to the indications reported in surgical technique regardless ∆PTS.


Subject(s)
Arthroplasty, Replacement, Knee , Knee Prosthesis , Osteoarthritis, Knee , Humans , Arthroplasty, Replacement, Knee/methods , Knee Joint/surgery , Range of Motion, Articular , Tibia/surgery , Osteoarthritis, Knee/surgery
3.
Ann Cardiol Angeiol (Paris) ; 70(3): 161-167, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33958189

ABSTRACT

PURPOSE: Spontaneous coronary artery dissection (SCAD) may occur in middle age population without any cardiovascular risk factor. We retrospectively evaluated anatomic features of 11 patients with SCAD using a coronary arteries computed tomography (CCT), compared to age and sex balanced patients who underwent CCT. MATERIAL AND METHODS: CCT was performed in 11 patients (7 females and 4 males) as follow-up in patients with SCAD (left anterior descending - LAD or circumflex artery - Cx) and compared, using the propensity score matching analysis, with 11 healthy patients. Several anatomic features were evaluated: Left main (LM) length, angle between descending coronary artery (LAD) and its first branch, angle between LAD and LM, distance from the annulus to RCA (a-RCA distance) and LM (a-LM distance) ostia and their ratio; ratio between LM length and length a-LM and tortuosity score of the vessel with SCAD. A fluid dynamic analysis has been performed to evaluate the effects on shear stress of vessels wall. RESULTS: LM length was significantly shorter in patients with SCAD versus healthy subjects (P=0.01) as well as LM length/a-LM (P=0.03) and the angle between LAD and the first adjacent branch was sharper (P<0.01). Tortuosity score showed a statistically significant difference between groups (P<0.001). Fluid dynamic analysis demonstrates that, in SCAD group, an angle<90 degree is present at the first bifurcation and it can be a cause of increased strain on vessel wall in patients with high tortuosity of coronary artery. CONCLUSION: Tortuosity and angle between the LAD and the adjacent arterial branch combined may determine increased shear stress on the vessel wall that increases the risk of SCAD.


Subject(s)
Computed Tomography Angiography , Coronary Angiography/methods , Coronary Vessel Anomalies/diagnostic imaging , Propensity Score , Vascular Diseases/congenital , Age Factors , Case-Control Studies , Coronary Vessel Anomalies/etiology , Coronary Vessel Anomalies/physiopathology , Coronary Vessels/diagnostic imaging , Coronary Vessels/pathology , Coronary Vessels/physiopathology , Female , Hemorheology/physiology , Humans , Male , Middle Aged , Retrospective Studies , Sex Factors , Vascular Diseases/diagnostic imaging , Vascular Diseases/etiology , Vascular Diseases/physiopathology
4.
J Hazard Mater ; 413: 125419, 2021 07 05.
Article in English | MEDLINE | ID: mdl-33930960

ABSTRACT

Nowadays, asbestos-containing wastes (ACW) still represent an important environmental problem and a severe health hazard due to the well known pulmonary diseases derived from asbestos fibers inhalation. Except for a very few cases, ACW are currently confined in controlled landfills, giving rise to increasingly high amounts of still hazardous wastes. A promising alternative to landfill confinement is represented by ACW inertization, but the high cost of the inertization processes so far proposed by the scientific community have hampered the creation of actually operative plants. In this paper, we explore the possibility to use an innovative process that ensures the obtainment of asbestos-free inert material in an exceptionally short processing time, thus greatly reducing cost-related problems. The efficacy of the inertization process has been verified through accurate mineralogical investigations on both chrysotile and crocidolite de-activated fibers, through X-ray diffraction, scanning and transmission electron microscopy. Overall mineralogical, microstructural and granulometric characteristics of the inert bulk material suggest that it could be successfully re-used as a secondary raw material in ceramic industries. This innovative inertization procedure could therefore provide an effective and economically sustainable solution for ACW management.

5.
J Mech Behav Biomed Mater ; 115: 104294, 2021 03.
Article in English | MEDLINE | ID: mdl-33383376

ABSTRACT

The valve replacement therapy is the standard treatment for severe heart valve diseases. Nowadays, two types of commercial prosthesis are available: mechanical and biological, but both of them have severe limitations. Moreover, alternative therapeutic approach for valve replacement, based on minimally invasive techniques (MIAVR), motivates the search for new valve materials. In this study a polyurethane-based self-expandable tri-leaflets heart valve compatible with MIAVR procedure is proposed. The device is based on the development, fabrication and characterization of three different elements: the leaflets, the polymeric stent for supporting the leaflets, and the external metallic stent for anchoring the valve to the native aortic root. The polymeric stent and the valve leaflets were fabricated using a thermoplastic silicone-polycarbonate-urethane using 3D printing and spray technology while the external metallic stent was made in nickel titanium (Nitinol) to obtain a self-expandable valve after the crimping process. The three elements were assembled in the completed device and tested by crimping, fatigue and fluid-dynamic test. The novel polymeric valve proposed showed promising results about valve crimping capabilities, durability and fluid dynamic performances. This approach could offer advantages such as low cost and to produce a tailor-made device basing on patient's imaging data. Moreover, the selected biomaterial offers the potential to have a device that could need of permanent anticoagulation and lack of calcification.


Subject(s)
Heart Valve Diseases , Heart Valve Prosthesis , Transcatheter Aortic Valve Replacement , Aortic Valve , Humans , Prosthesis Design , Stents
6.
Prostate Cancer Prostatic Dis ; 24(1): 150-155, 2021 03.
Article in English | MEDLINE | ID: mdl-32681155

ABSTRACT

BACKGROUND: To investigate if the PI-RADS score represents an effective tool in detecting prostate cancer in patients treated with a 5α-reductase inhibitor (dutasteride) and to identify dedicated total serum PSA and PSA density thresholds. METHODS: Between April 2015 and March 2018, 75 patients under dutasteride treatment underwent multi-parametric magnetic resonance imaging (mpMRI) scans and US/MRI fusion prostate biopsy. Lesions were classified into two groups: Group 1 included PI-RADS 4 and 5 lesions, whilst Group 2 included PI-RADS 3-4-5 lesions. Lesions in groups 1 and 2 were further divided according to the patients' history of previous prostate biopsy. RESULTS: Ninety-seven lesions were detected. In PI-RADS 4-5 group, mpMRI showed a sensitivity of 78.0% and a specificity of 78.7%. The positive predictive value (PPV) was 79.6% and the negative predictive value (NPV) 77.1%. In PI-RADS 3-4-5 group, sensitivity was 100%, specificity 21.3%, PPV 57.5%, NPV 100%. In PI-RADS 4-5 biopsy-naive group sensitivity was 71.4%, specificity 75.0%. PPV 78.9% and NPV 66.7%. In PI-RADS 4-5 non-biopsy-naive group sensitivity was 82.8%, specificity 80.6%, PPV 80%, and NPV 83.3%. PI-RADS 3-4-5 biopsy-naive group showed sensitivity 100%, specificity 31.3%, PPV 65.6%, NPV 100%. PI-RADS 3-4-5 non-biopsy-naive group showed sensitivity 100%, specificity 16.1%, PPV 52.7%, and NPV 100%. ROC curve analysis indicated a serum total PSA threshold of 6 ng/ml (AUC: 0.71-95% confidence interval: 0.60-0.81) and a PSA density >0.22 (AUC: 0.70-95% confidence interval: 0.6-0.81) as optimal cut-offs for recommending prostate biopsy. CONCLUSIONS: In our experience the PI-RADS score proved to be sufficiently accurate in predicting prostate cancer in patients under dutasteride therapy.


Subject(s)
Dutasteride/therapeutic use , Image-Guided Biopsy/methods , Magnetic Resonance Imaging/methods , Neoplasm Grading , Prostatic Neoplasms/diagnosis , Ultrasonography/methods , 5-alpha Reductase Inhibitors/therapeutic use , Aged , Aged, 80 and over , Biomarkers, Tumor/blood , Biopsy , Follow-Up Studies , Humans , Male , Middle Aged , Predictive Value of Tests , Prostate-Specific Antigen/blood , Prostatic Neoplasms/blood , Prostatic Neoplasms/drug therapy , ROC Curve , Retrospective Studies
7.
Eur J Nucl Med Mol Imaging ; 47(13): 3018-3032, 2020 12.
Article in English | MEDLINE | ID: mdl-32451604

ABSTRACT

AIM: Transarterial radioembolization (TARE) is, by all standards, a radiation therapy. As such, according to Euratom Directive 2013/59, it should be optimized by a thorough treatment plan based on the distinct evaluation of absorbed dose to the lesions and to the non-tumoural liver (two-compartment dosimetry). Since the dosimetric prediction with 99mTc albumin macro-aggregates (MAA) of non-tumoural liver is much more accurate than the same prediction on lesions, treatment planning should focus on non-tumoural liver rather than on lesion dosimetry. The aim of this study was to determine a safety limit through the analysis of pre-treatment dosimetry with 99mTc-MAA single photon emission computed tomography (SPECT/CT), in order to deliver the maximum tolerable absorbed dose to non-tumoural liver. METHODS: Data from intermediate/advanced hepato-cellular carcinoma (HCC) patients treated with 90Y glass microspheres were collected in this single-arm retrospective study. Injection was always lobar, even in case of bilobar disease, to avoid treating the whole liver in a single session. A three-level definition of liver decompensation (LD) was introduced, considering toxicity only in cases of liver decompensation requiring medical action (LD type C, LDC). We report LDC rates, receiver operating characteristic (ROC) analysis between LDC and NO LDC absorbed dose distributions, normal tissue complication probability (NTCP) curves and uni- and multivariate analysis of risk factors associated with toxicity. RESULTS: A 6-month timeline was defined as necessary to capture all treatment-related toxicity events. Previous transarterial chemoembolization (TACE), presence or extension of portal vein tumoural thrombosis (PVTT) and tumour pattern (nodular versus infiltrative) were not associated with tolerance to TARE. On the contrary, at the multivariate analysis, the absorbed dose averaged over the whole non-tumoural liver (including the non-injected lobe) was a prognostic indicator correlated with liver decompensation (odds ratio = 4.24). Basal bilirubin > 1.1 mg/dL was a second even more significant risk factor (odds ratio = 6.35). NTCP analysis stratified with this bilirubin cut-off determined a 15% liver decompensation risk at 50 Gy/90 Gy for bilirubin >/< 1.1 mg/dL. These results are valid for a 90Y glass microsphere administration 4 days after the reference time. CONCLUSION: Given the low predictive accuracy of 99mTc-MAA on lesion absorbed dose reported by several authors, an optimized TARE with 90Y glass microspheres with lobar injection 4 days after reference time should aim at an absorbed dose averaged over the whole non-tumoural liver of 50 Gy/90 Gy for basal bilirubin higher/lower than 1.1 mg/dL, respectively.


Subject(s)
Carcinoma, Hepatocellular , Chemoembolization, Therapeutic , Embolization, Therapeutic , Liver Neoplasms , Carcinoma, Hepatocellular/diagnostic imaging , Carcinoma, Hepatocellular/radiotherapy , Embolization, Therapeutic/adverse effects , Glass , Humans , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/radiotherapy , Microspheres , Retrospective Studies , Technetium Tc 99m Aggregated Albumin , Tomography, Emission-Computed, Single-Photon , Yttrium Radioisotopes/adverse effects
8.
Cardiovasc Intervent Radiol ; 43(6): 889-896, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32342158

ABSTRACT

PURPOSE: To report the preliminary results of a novel full percutaneous interbody fusion technique for the treatment of degenerative disc disease (DDD) resistant to conservative treatment with posterior stabilization with rods and screws and transforaminal placement of an 8-mm-width intradiscal cage. MATERIALS AND METHODS: A total of 79 patients with lumbar spine DDD resistant to medical therapy and/or spondylolisthesis up to grade 2 were treated. We performed preoperative X-rays, CT and MRI. The outcomes were assessed using the VAS score and the Oswestry Disability Index at a 1-, 6- and 12-month follow-up and also included X-rays to evaluate the correct bone fusion and the absence of complications. RESULTS: Mean operation time was 130 min, and mean postoperative time until hospital discharge was 2 days. Postoperative values for VAS scores and ODI improved significantly compared to preoperative data: Mean preprocedural VAS was 7.49 ± 0.69 and decreased at 12-month follow-up to 1.31 ± 0.72, and mean preprocedural ODI was 29.94 ± 1.67 and decreased at 12-month follow-up to 12.75 ± 1.44. No poor results were reported, and no postprocedural sequelae were observed. CONCLUSIONS: In our experience, this preliminary report shows a feasible and safe full percutaneous alternative procedure and represents a minimally invasive management of degenerative disc disease with low back pain resistant to medical therapy with or without lumbar spondylolisthesis up to grade 2.


Subject(s)
Internal Fixators , Intervertebral Disc Degeneration/diagnostic imaging , Intervertebral Disc Degeneration/surgery , Spinal Fusion/methods , Aged , Female , Follow-Up Studies , Humans , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/surgery , Magnetic Resonance Imaging , Male , Minimally Invasive Surgical Procedures/methods , Postoperative Period , Radiography , Retrospective Studies , Tomography, X-Ray Computed , Treatment Outcome
10.
Rev. argent. endocrinol. metab ; 55(3): 1-10, set. 2018. graf
Article in Spanish | LILACS | ID: biblio-1041739

ABSTRACT

RESUMEN Material y métodos Estudio prospectivo multicéntrico. Se incluyeron 174 pacientes con CDT tratados consecutivamente desde junio 2014 hasta mayo 2015. Se los dividió en 2 grupos (ablacionados y no ablacionados) con 87 pacientes incluidos en cada uno. La respuesta inicial al tratamiento se determinó con la medición de tiroglobulina, anticuerpos anti-tiroglobulina y ecografía de cuello. Resultados Se compararon las características basales de ambos grupos y no se evidenciaron diferencias estadísticamente significativas: sexo femenino 84% y 88% (p = 0,5); edad promedio de 46,8 y 47,5 años (p = 0,7); carcinoma papilar variedad clásico 68% y 75,9% (p = 0,15), respectivamente. El resto de las características basales como tamaño tumoral, bilateralidad, multifocalidad, tiroiditis de Hashimoto y estadio tumoral tampoco mostraron diferencias significativas. La evaluación de la respuesta inicial al tratamiento se realizó en 64 pacientes del grupo ablacionado y en 76 del grupo no ablacionado. Se observó una respuesta excelente en 81% de pacientes ablacionados vs. 87% del grupo no ablacionado, con una frecuencia de respuesta estructural incompleta de 1,6% y 1,4%, respectivamente, (p = 0,9). Un 17% de los ablacionados y 12% de los no ablacionados presentaron una respuesta indeterminada. Conclusión: Los pacientes de bajo riesgo, ablacionados o no, presentan similares frecuencias de respuesta inicial excelente y estructural incompleta. El seguimiento a largo plazo podrá definir si estas respuestas iniciales se mantienen en el tiempo, lo que permitirá reducir la indicación de ablación con radioyodo en este grupo de pacientes con CDT.


ABSTRACT Patients and methods We included 174 patients; 87 patients in each group (ablated and nonablated). Assessment of the initial response to treatment was performed by measurement of thyroglobulin and anti-thyroglobulin antibodies and by neck ultrasonography. Results Baseline characteristics of both groups were compared, and no statistically significant differences were found: female sex 84% and 88,5%, respectively, (p = 0.5); mean age of 46.8 and 47.5 years, respectively (p = 0.7); papillary carcinoma classic variant 68% and 75.9%, respectively (p = 0.15). The remaining of the baseline characteristics such as tumor size, presence of bilaterality, multifocality, Hashimoto's thyroiditis and tumor stage were not statistically significant, either. The evaluation of the response to treatment was finally performed in 64 patients from the ablated group and in 76 from the non-ablated group. An excellent response to treatment was observed in 81% of ablated patients vs. 87% of the non-ablated group, with a frequency of structural incomplete response of 1.6% and 1.4%, respectively (p = 0.9). On the other hand, 17% and 12% of patients in each group had an indeterminate response. Conclusion Low-risk ablated and non-ablated patients have a similar frequency of excellent initial and structural incomplete response to treatment. Long-term follow-up is needed to establish whether these initial responses are maintained over time, and thus further refine the indications of RA in this group of patients with DTC.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Thyroid Neoplasms/surgery , Thyroid Neoplasms/therapy , Treatment Outcome , Reaction Time/immunology , Recurrence , Thyroidectomy/rehabilitation , Radiosurgery/rehabilitation
11.
Accid Anal Prev ; 107: 40-47, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28783544

ABSTRACT

Drink-driving remains a major road safety concern that creates a significant social burden. Licence disqualification continues to play a key role in drink driving deterrence and sanctions together with police enforcement to address the problem in most motorised countries. However, on-going questions remain regarding the differing effect of licence disqualification periods between first time and repeat offenders, and between other sub-groups of offenders. As a result, this study aimed to determine whether: (a) differences exist in re-offence rates of convicted drink-drivers between: the period between committing the drink-driving offence and licence disqualification (pre-licence disqualification), during the period of licence disqualification, and after being re-licensed (post-licence restoration); and (b) differential effects of offence rates are evident based on Blood Alcohol Content (BAC), gender, age, repeat offender status and crash involvement at the time of offence. The sample consisted of 29,204 drink-driving offenders detected in Victoria, Australia between 1 January 1996 and 30 September 2002. The analysis indicated that licence disqualifications were effective as drink-driving offenders had a significantly lower rate of offending (both drink-driving and other traffic offences) during licence disqualifications compared to pre-licence disqualification and post-licence restoration periods. The influence of licence disqualification appeared to extend beyond the disqualification period, as offence rates were lower during post-licence restoration than during pre-licence disqualification. Interestingly, the highest rate of offending (both for drink-driving and other traffic offences) was during the pre-licence disqualification period, which suggests offenders are particularly vulnerable to drink and drive while waiting to be sanctioned. A consistent pattern of results was evident across genders and age groups. Additionally, those who were involved in a crash at the same time as their index offence had lower offence rates (compared to those who were not involved in a crash) for all periods, although for general traffic offences, the offence rate was highest in the post-licence restoration period for those who had a crash at index offence. This indicates that being involved in a crash may deter these offenders, at least in the short-term. The implications of the results for managing both first time and repeat offenders are discussed.


Subject(s)
Accidents, Traffic/psychology , Criminals/psychology , Driving Under the Influence/statistics & numerical data , Adolescent , Adult , Blood Alcohol Content , Chi-Square Distribution , Driving Under the Influence/psychology , Female , Humans , Licensure/legislation & jurisprudence , Male , Middle Aged , Time Factors , Victoria , Young Adult
12.
Case Rep Radiol ; 2017: 2167364, 2017.
Article in English | MEDLINE | ID: mdl-28316856

ABSTRACT

We present a case of giant Splenorenal Shunt (SRS) associated with portal vein thrombosis in a 37-year-old woman with a twelve-year history of autoimmune hepatitis/primary biliary cholangitis overlap syndrome. At the moment of the CT examination laboratory tests showed creatinine 1.5 mg/dl, bilirubin 1.5 mg/dl, INR 3, and Na 145 mmol/l and the Model End-Stage Liver Disease score was 24. Extensive calcified thrombosis causing complete occlusion of the portal vein lumen and partially occluding the origin of the superior mesenteric vein was present and a small calcified thrombus in the Splenic Vein lumen was also evident. SRS was located among the spleen hilum and the left kidney with a maximum diameter of 3.25 cm and was associated with dilatation of left renal vein and inferior vena cava. After a multidisciplinary evaluation the patient was put on the Regional Liver Transplant waiting list and liver transplantation was performed successfully. Although portal vein thrombosis and SRS are common occurrences in cirrhotic patients, the impact in the natural history of the disease is still unclear. Careful management and accurate imaging protocols are essential in the evaluation of those patients.

13.
Phys Rev E ; 93(6): 062611, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27415324

ABSTRACT

Focusing on shear-stress fluctuations, we investigate numerically a simple generic model for self-assembled transient networks formed by repulsive beads reversibly bridged by ideal springs. With Δt being the sampling time and t_{☆}(f)∼1/f the Maxwell relaxation time (set by the spring recombination frequency f), the dimensionless parameter Δx=Δt/t_{☆}(f) is systematically scanned from the liquid limit (Δx≫1) to the solid limit (Δx≪1) where the network topology is quenched and an ensemble average over m-independent configurations is required. Generalizing previous work on permanent networks, it is shown that the shear-stress relaxation modulus G(t) may be efficiently determined for all Δx using the simple-average expression G(t)=µ_{A}-h(t) with µ_{A}=G(0) characterizing the canonical-affine shear transformation of the system at t=0 and h(t) the (rescaled) mean-square displacement of the instantaneous shear stress as a function of time t. This relation is compared to the standard expression G(t)=c[over ̃](t) using the (rescaled) shear-stress autocorrelation function c[over ̃](t). Lower bounds for the m configurations required by both relations are given.

14.
Cell Death Dis ; 6: e1948, 2015 Oct 29.
Article in English | MEDLINE | ID: mdl-26512958

ABSTRACT

Molecular mechanisms protecting cardiomyocytes from stress-induced death, including tension stress, are essential for cardiac physiology and defects in these protective mechanisms can result in pathological alterations. Bcl2-associated athanogene 3 (BAG3) is expressed in cardiomyocytes and is a component of the chaperone-assisted autophagy pathway, essential for homeostasis of mechanically altered cells. BAG3 ablation in mice results in a lethal cardiomyopathy soon after birth and mutations of this gene have been associated with different cardiomyopathies including stress-induced Takotsubo cardiomyopathy (TTC). The pathogenic mechanism leading to TTC has not been defined, but it has been suggested that the heart can be damaged by excessive epinephrine (epi) spillover in the absence of a protective mechanism. The aim of this study was to provide more evidence for a role of BAG3 in the pathogenesis of TTC. Therefore, we sequenced BAG3 gene in 70 TTC patients and in 81 healthy donors with the absence of evaluable cardiovascular disease. Mutations and polymorphisms detected in the BAG3 gene included a frequent nucleotide change g2252c in the BAG3 3'-untranslated region (3'-UTR) of Takotsubo patients (P<0.05), resulting in loss of binding of microRNA-371a-5p (miR-371a-5p) as evidenced by dual-luciferase reporter assays and argonaute RNA-induced silencing complex catalytic component 2/pull-down assays. Moreover, we describe a novel signaling pathway in cardiomyocytes that leads to BAG3 upregulation on exposure to epi through an ERK-dependent upregulation of miR-371a-5p. In conclusion, the presence of a g2252c polymorphism in the BAG3 3'-UTR determines loss of miR-371a-5p binding and results in an altered response to epi, potentially representing a new molecular mechanism that contributes to TTC pathogenesis.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Apoptosis Regulatory Proteins/genetics , Epinephrine/pharmacology , MicroRNAs/physiology , Mutation , Takotsubo Cardiomyopathy/genetics , Adaptor Proteins, Signal Transducing/metabolism , Apoptosis Regulatory Proteins/metabolism , Female , Humans , MicroRNAs/genetics , MicroRNAs/metabolism , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Up-Regulation/drug effects
15.
Rev. argent. endocrinol. metab ; 51(1): 1-7, abr. 2014. ilus, tab
Article in Spanish | LILACS | ID: lil-750593

ABSTRACT

La interferencia producida por los anticuerpos antitiroglobulina (aTg) en la determinación de Tiroglobulina (Tg) ha sido bien estudiada, sin embargo la interferencia que puede producir esta última sobre la determinación de los anticuerpos no está clara. Objetivo: Investigar la interferencia que la Tg puede producir sobre la determinación de los aTg en el líquido de lavado de aguja de punción ganglionar. Material y Métodos: Se estudiaron retrospectivamente las muestras provenientes de la punción de adenopatías cervicales sospechosas de 19 pacientes tiroidectomizados por Cáncer Diferenciado de Tiroides (CDT). La punción se realizó con aguja 22 G bajo guía ecográfica y luego de la preparación del extendido para el estudio citológico se procedió al lavado de la aguja con 500 µl de solución fisiológica para determinar Tg y aTg. La medición de Tg se hizo por ensayo quimioluminiscente. Los aTg se midieron utilizando dos ensayos uno no competitivo quimioluminiscente (Q) y otro competitivo electroquimioluminiscente (Eq). Se consideraron aTg negativos valores < 20 UI/ml. Se realizaron diluciones de la muestra de uno de los pacientes para el estudio de interferencia. Resultados: En todas las muestras las concentraciones de Tg mostraron valores muy elevados (rango: 15.185 -1.141.275 ng/ml). Los resultados de los aTg fueron negativos en el 100 % de las muestras cuando se midieron por el método no competitivo (Q) y francamente positivos en un rango de 106 a > 4.000 UI/ml cuando se midieron por el método competitivo (Eq), siendo estos valores proporcionales a la concentración de Tg en la muestra. Se observó una falta de linealidad cuando se realizó ensayo de dilución a muestras de concentración elevada de aTg medidas por Eq. Los aTg por Eq se negativizaron a concentraciones de Tg inferiores a 3.000 ng/ml. Los aTg medidos por Q arrojaron valores negativos en todas las diluciones. Todos estos pacientes presentaban aTg negativos en suero por Q y Eq. Conclusión: Las altas concentraciones de Tg interfieren en la medición de aTg cuando los mismos son medidos por un método competitivo. La interferencia es proporcional a las concentraciones de Tg presentes en la muestra. Se recomienda que en los líquidos de lavado de aguja de punción ganglionar los aTg sean medidos por un método no competitivo ya que no parece estar interferido por las altas concentraciones de Tg característica de los ganglios metastásicos. La detección de esta interferencia no modificó el diagnóstico ni la conducta clínica en ningún caso, sin embargo es importante conocerla con el fin de no concluir erróneamente sobre la positividad de los anticuerpos en los ganglios cuando estos son medidos por un ensayo competitivo. Rev Argent Endocrinol Metab 51:1-7, 2014 Los autores declaran no poseer conflictos de interés.


Thyroglobulin antibodies (TgAb) interference with thyroglobulin (Tg) measurements has been well studied; however, Tg interference with TgAb is unclear. Objective: To investigate how TgAb may interfere with Tg measurement in the washout fluid from lymph node fine-needle aspiration biopsy. Materials and Methods: We retrospectively studied the samples obtained by aspiration of suspicious cervical lymph nodes from 19 patients post thyroidectomy for Differentiated Thyroid Cancer (DTC). The puncture was performed with a 22 G needle under ultrasound guidance. After preparation of cytological specimens, the needle was washed with 500 ul of saline solution to determine Tg and TgAb. Tg was measured by chemilumi­nescent assay and TgAb was measured using two assays: a non-competitive chemiluminescent assay (Q) and a competitive electrochemiluminescence assay (Eq). Values of TgAb below 20 UI/ml were considered negative. Appropriate dilutions of the sample of one of the patients were performed in order to study interference. Results: In all samples tested, concentrations showed very high Tg values (range: 15.185 - 1.141.275 ng/ml). TgAb results were negative in all the samples measured by the non-competitive method. Results were clearly positive in a range of 106 to > 4.000 IU/ml when the competitive assay (Eq) was used, being proportional to Tg concentrations in the samples. A lack of linearity was observed when a dilution assay was performed in samples of high TgAb concentrations measured by Eq. When Tg concentrations were below 3.000 ng / ml, TgAb became negative when measured by Eq. TgAbs measured by Q were negative in all dilutions. TgAbs in serum were negative in all patients by the two methodologies (Q and Eq). Conclusion: High levels of Tg interfere with TgAb measurement when a competitive method is used. The interference is proportional to the concentrations of Tg. It is recommended that in the wash-out fluid from fine needle aspiration, TgAbs should be measured by a non-competitive method since there appears to be no interference from the high concentrations of Tg characteristic of metastatic nodes. The detection of this interference did not change the diagnosis or clinical management in any case; however, it is important to be aware of such interference so as not to make erroneous conclusions about the positivity of TgAbs in lymph nodes when a competitive method is used. Rev Argent Endocrinol Metab 51:1-7, 2014 No financial conflicts of interest exist.

16.
Diabetes Res Clin Pract ; 103(3): 444-51, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24529563

ABSTRACT

AIM: To investigate the effects of uncomplicated vaginal delivery and epidural analgesia on fetal acid-base parameters in women with gestational diabetes (GDM) compared with controls. METHODS: A retrospective case-control study of 142 women with gestational diabetes and 284 controls. To evaluate the effect of diabetes and analgesia on acid-base status correcting for potential confounders we used ordered logistic equations including quartiles of fetal arterial acid-base parameters collected at birth as outcomes and categories of diabetes and epidural analgesia as explanatory variables. RESULTS: In the GDM group cord base deficit (-2.63 mmol/l, interquartile range [IQR]=4.2 to -0.65 mmol/l vs. -1.9 mmol/l, IQR=-3.3 to -0.2 mmol/l, p=0.009, odds ratio (OR)=1.51, 95% confidence interval (CI)=1.04-2.18) was lower and concentration of calcium higher (1.49 mmol/l, IQR=1.42-1.56 mmol/l vs. 1.47 mmol/l, IQR=1.41-1.51 mmol/l, p=0.009, OR=1.69, 95% CI=1.12-2.56) compared with controls. Epidural analgesia in the GDM group was associated with reduced cord concentration of glucose (84.0mg/dl [4.7 mmol/l], IQR=70-103.3mg/dl vs. 92.5mg/dl [5.1 mmol/l], IQR=76.5-121.8 mg/dl, p=0.004), lactate (2.65 mmol/l (IQR=1.80-4.20) vs. 3.70 mmol/l (IQR=2.90-5.55 mmol/l), p=0.002) and less pronounced base deficit (-2.05 mmol/l, IQR=-3.90 to -0.17 mmol/l vs. -2.8, IQR=-5.57 to -1.05 mmol/l, p=0.01, OR=0.7, 95% CI=0.49-0.99). CONCLUSIONS: In uncomplicated pregnancies and deliveries, well-controlled gestational diabetes mellitus has potentially significant detrimental effects on fetal acid-base status at birth. Epidural analgesia reduces cord arterial glucose and lactates.


Subject(s)
Acid-Base Equilibrium/physiology , Analgesia, Epidural , Delivery, Obstetric , Diabetes, Gestational/physiopathology , Fetal Blood/chemistry , Umbilical Arteries/physiology , Adult , Blood Glucose/analysis , Case-Control Studies , Female , Glucose Tolerance Test , Humans , Pregnancy , Prognosis , Retrospective Studies
17.
J Chem Phys ; 134(23): 234901, 2011 Jun 21.
Article in English | MEDLINE | ID: mdl-21702579

ABSTRACT

By Monte Carlo simulations of a variant of the bond-fluctuation model without topological constraints, we examine the center-of-mass (COM) dynamics of polymer melts in d = 3 dimensions. Our analysis focuses on the COM displacement correlation function C(N)(t)≈∂(t) (2)h(N)(t)/2, measuring the curvature of the COM mean-square displacement h(N)(t). We demonstrate that C(N)(t) ≈ -(R(N)∕T(N))(2)(ρ∗/ρ) f(x = t/T(N)) with N being the chain length (16 ≤ N ≤ 8192), R(N) ∼ N(1/2) is the typical chain size, T(N) ∼ N(2) is the longest chain relaxation time, ρ is the monomer density, ρ(*)≈N/R(N) (d) is the self-density, and f(x) is a universal function decaying asymptotically as f(x) ∼ x(-ω) with ω = (d + 2) × α, where α = 1/4 for x ≪ 1 and α = 1/2 for x ≫ 1. We argue that the algebraic decay NC(N)(t) ∼ -t(-5/4) for t ≪ T(N) results from an interplay of chain connectivity and melt incompressibility giving rise to the correlated motion of chains and subchains.


Subject(s)
Molecular Dynamics Simulation , Polymers/chemistry , Algorithms , Diffusion , Monte Carlo Method
18.
Anal Bioanal Chem ; 397(6): 2039-49, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20506014

ABSTRACT

In this paper we describe recent applications of micro-infrared imaging in the Earth sciences. We address, in particular, the use of Fourier-transform infrared (FTIR) spectroscopy in characterizing the zoning and speciation of H and C in a variety of geological materials, including microporous minerals, nominally anhydrous volcanic minerals (NAMs), and crystal inclusions. These investigations show that use of the modern techniques of FTIR imaging enables detection of the zoning of volatile species across the studied samples, and possible configuration changes of structurally-bound carbon molecular species (e.g., CO(2) vs CO(3)) during crystal growth. Such features, which are not accessible with other micro-analytical techniques, may provide information about the physicochemical properties which act as constraints in the genesis of the samples, and important information about the evolution of the geological system. Tests performed with focal-plane-array detectors (FPA) show that resolution close to the diffraction limit can be achieved if the amounts of the target molecules in the sample are substantially different. We also point out the possibility of using FTIR imaging for investigations under non-ambient conditions.

19.
Eur Phys J E Soft Matter ; 31(3): 229-37, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20336342

ABSTRACT

Following Flory's ideality hypothesis, the chemical potential of a test chain of length n immersed into a dense solution of chemically identical polymers of length distribution P(N) is extensive in n . We argue that an additional contribution deltamu(c)(n) approximately +1/rho (sqrt[n]) arises (rho being the monomer density) for all P(N) if n " which can be traced back to the overall incompressibility of the solution leading to a long-range repulsion between monomers. Focusing on Flory-distributed melts, we obtain deltamu(c)(n) approximately equal to (1 - 2n/ ) / rho (sqrt[n]) for n " (2) , hence, deltarho(c)(n) approximately equal to -1/rho (sqrt[n]) if n is similar to the typical length of the bath . Similar results are obtained for monodisperse solutions. Our perturbation calculations are checked numerically by analyzing the annealed length distribution P(N) of linear equilibrium polymers generated by Monte Carlo simulation of the bond fluctuation model. As predicted we find, e.g., the non-exponentiality parameter K (p) = 1 - (p)! (p) to decay as K (p) approximately equal to 1/ (sqrt[]) for all moments p of the distribution.

20.
J Bone Joint Surg Br ; 91(12): 1545-9, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19949114

ABSTRACT

This study evaluated the feasibility of using published data from more than one register to define the performance of different hip implants. In order to obtain estimates of performance for specific types of hip system from different register, we analysed data from the annual reports of five national and one Italian regional register. We extracted the number of implants and rates of implant survival at different periods of follow-up. Our aim was to assess whether estimates of cumulative survival rate were comparable with data from registers from different countries, and our conclusion was that such a comparison could only be performed incompletely.


Subject(s)
Arthroplasty, Replacement, Hip/standards , Hip Prosthesis/standards , Quality Assurance, Health Care/standards , Registries/statistics & numerical data , Aged , Arthroplasty, Replacement, Hip/mortality , Arthroplasty, Replacement, Hip/statistics & numerical data , Humans , Prosthesis Design , Scandinavian and Nordic Countries , Treatment Outcome
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