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1.
Article in English | MEDLINE | ID: mdl-38748971

ABSTRACT

OBJECTIVE: To reach a Delphi-generated international expert consensus on the diagnosis, prognostic, management, and core outcome set (COS) of fetal Lower Urinary Tract Obstruction (LUTO). METHODS: A three-round Delphi procedure was conducted among an international panel of LUTO experts. The panel was provided with a list of literature review-generated parameters for the diagnosis, prognostic, management, and outcomes. A parallel procedure was conducted along with patient groups during the development of COS. RESULTS: A total of 160 experts were approached, of whom 99 completed the first round and 80 (80/99, 80.8%) completed all three rounds. In the first trimester, an objective measurement of longitudinal bladder diameter (with ≥7 mm being abnormal) should be used to suspect LUTO. In the second trimester, imaging parameters of LUTO could include: a) an enlarged bladder, b) a keyhole sign, c) bladder wall thickening, d) bilateral hydro (uretero) nephrosis, and e) male sex. There was a lack of consensus on the current prognostic scoring literature. However, experts agreed on the value of amniotic fluid volume (< 24 weeks) to predict survival and that the value of fetal intervention is to improve neonatal survival. While experts endorsed the role of sonographic parameters of renal dysplasia, at least one vesicocentesis, and urine biochemistry for prognosis and counseling, these items did not reach a consensus for determining fetal intervention candidacy. On the other hand, imaging parameters suggestive of LUTO, absence of life-limiting structural or genetic anomalies, gestational age of ≥16 weeks, and oligohydramnios defined as deepest vertical pocket (DVP) <2 cm should be used as candidacy criteria for fetal intervention based on experts' consensus. If a bladder refill was evaluated, it should be assessed subjectively. Vesicoamniotic shunt should be the first line of fetal intervention. In the presence of suspected fetal renal failure, serial amnioinfusion should only be offered as an experimental procedure under research protocols. The core outcome set for future studies was agreed upon. CONCLUSION: International consensus on the diagnosis, prognosis, and management of fetal LUTO, as well as the Core Outcome Set, should inform clinical care and research to optimize perinatal outcomes. This article is protected by copyright. All rights reserved.

2.
Ultrasound Obstet Gynecol ; 58(4): 582-589, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33880811

ABSTRACT

OBJECTIVE: A trial comparing prenatal with postnatal open spina bifida (OSB) repair established that prenatal surgery was associated with better postnatal outcome. However, in the trial, fetal surgery was carried out through hysterotomy. Minimally invasive approaches are being developed to mitigate the risks of open maternal-fetal surgery. The objective of this study was to investigate the impact of a novel neurosurgical technique for percutaneous fetoscopic repair of fetal OSB, the skin-over-biocellulose for antenatal fetoscopic repair (SAFER) technique, on long-term postnatal outcome. METHODS: This study examined descriptive data for all patients undergoing fetoscopic OSB repair who had available 12- and 30-month follow-up data for assessment of need for cerebrospinal fluid (CSF) diversion and need for bladder catheterization and ambulation, respectively, from eight centers that perform prenatal OSB repair via percutaneous fetoscopy using a biocellulose patch between the neural placode and skin/myofascial flap, without suture of the dura mater (SAFER technique). Univariate and multivariate logistic regression analyses were used to examine the effect of different factors on need for CSF diversion at 12 months and ambulation and need for bladder catheterization at 30 months. Potential cofactors included gestational age at fetal surgery and delivery, preoperative ultrasound findings of anatomical level of the lesion, cerebral lateral ventricular diameter, lesion type and presence of bilateral talipes, as well as postnatal findings of CSF leakage at birth, motor level, presence of bilateral talipes and reversal of hindbrain herniation. RESULTS: A total of 170 consecutive patients with fetal OSB were treated prenatally using the SAFER technique. Among these, 103 babies had follow-up at 12 months of age and 59 had follow-up at 30 months of age. At 12 months of age, 53.4% (55/103) of babies did not require ventriculoperitoneal shunt or third ventriculostomy. At 30 months of age, 54.2% (32/59) of children were ambulating independently and 61.0% (36/59) did not require chronic intermittent catheterization of the bladder. Multivariate logistic regression analysis demonstrated that significant prediction of need for CSF diversion was provided by lateral ventricular size and type of lesion (myeloschisis). Significant predictors of ambulatory status were prenatal bilateral talipes and anatomical and functional motor levels of the lesion. There were no significant predictors of need for bladder catheterization. CONCLUSION: Children who underwent prenatal OSB repair via the percutaneous fetoscopic SAFER technique achieved long-term neurological outcomes similar to those reported in the literature after hysterotomy-assisted OSB repair. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Subject(s)
Fetoscopy/statistics & numerical data , Neurosurgical Procedures/statistics & numerical data , Spina Bifida Cystica/surgery , Urinary Catheterization/statistics & numerical data , Ventriculostomy/statistics & numerical data , Walking/statistics & numerical data , Female , Fetoscopy/methods , Fetus/surgery , Follow-Up Studies , Gestational Age , Humans , Hysterotomy/methods , Hysterotomy/statistics & numerical data , Infant , Infant, Newborn , Logistic Models , Neurosurgical Procedures/methods , Postoperative Period , Pregnancy , Spina Bifida Cystica/complications , Spina Bifida Cystica/embryology , Treatment Outcome , Urinary Bladder , Ventriculoperitoneal Shunt/statistics & numerical data
3.
Appl Radiat Isot ; 166: 109359, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32739748

ABSTRACT

Ionizing and non-ionizing radiations are part of our daily life, and when organisms are exposed to them for a long time, they may experience their lethal or sublethal effects. For this reason, technologies have been created to quantify them. In this study, Internet of Things (IoT) was used through connecting gamma meters and a low-cost UV radiation device. The validation of this structure was performed with meters calibrated in certified laboratories. The validation results matched those obtained by the other devices, with an error of 2%.

4.
Oncologist ; 23(6): 670-678, 2018 06.
Article in English | MEDLINE | ID: mdl-29490940

ABSTRACT

BACKGROUND: Several breast cancer (BC) trials have adopted pathological complete response (pCR) as a surrogate marker of long-term treatment efficacy. In patients with luminal subtype, pCR seems less important for outcome prediction. BC is a heterogeneous disease, which is evident in residual tumors after neoadjuvant-chemotherapy (NAC). This study evaluates changes in Ki67 in relation to disease-free survival (DFS) and overall survival (OS) in patients without pCR. SUBJECTS, MATERIALS, AND METHODS: Four hundred thirty-five patients with stage IIA-IIIC BC without pCR after standard NAC with anthracycline and paclitaxel were analyzed. We analyzed the decrease or lack of decrease in the percentage of Ki67-positive cells between core biopsy samples and surgical specimens and correlated this value with outcome. RESULTS: Twenty-five percent of patients presented with luminal A-like tumors, 45% had luminal B-like tumors, 14% had triple-negative BC, 5% had HER2-positive BC, and 11% had triple-positive BC. Patients were predominantly diagnosed with stage III disease (52%) and high-grade tumors (46%). Median Ki67 level was 20% before NAC, which decreased to a median of 10% after NAC. Fifty-seven percent of patients had a decrease in Ki67 percentage. Ki67 decrease significantly correlated with better DFS and OS compared with no decrease, particularly in the luminal B subgroup. Multivariate analysis showed that nonreduction of Ki67 significantly increased the hazard ratio of recurrence and death by 3.39 (95% confidence interval [CI] 1.8-6.37) and 7.03 (95% CI 2.6-18.7), respectively. CONCLUSION: Patients without a decrease in Ki67 in residual tumors after NAC have poor prognosis. This warrants the introduction of new therapeutic strategies in this setting. IMPLICATIONS FOR PRACTICE: This study evaluates the change in Ki67 percentage before and after neoadjuvant chemotherapy (NAC) and its relationship with survival outcomes in patients with breast cancer who did not achieve complete pathological response (pCR). These patients, a heterogeneous group with diverse prognoses that cannot be treated using a single algorithm, pose a challenge to clinicians. This study identified a subgroup of these patients with a poor prognosis, those with luminal B-like tumors without a Ki67 decrease after NAC, thus justifying the introduction of new therapeutic strategies for patients who already present a favorable prognosis (luminal B-like with Ki67 decrease).


Subject(s)
Breast Neoplasms/complications , Ki-67 Antigen/metabolism , Neoadjuvant Therapy/adverse effects , Adult , Aged , Aged, 80 and over , Breast Neoplasms/pathology , Female , Humans , Middle Aged
6.
Ultrasound Obstet Gynecol ; 52(4): 458-466, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29314321

ABSTRACT

OBJECTIVE: We have described previously our percutaneous fetoscopic technique for the treatment of open spina bifida (OSB). However, approximately 20-30% of OSB defects are too large to allow primary skin closure. Here we describe a modification of our standard technique using a bilaminar skin substitute to allow closure of large spinal defects. The aim of this study was to report our clinical experience with the use of a bilaminar skin substitute and a percutaneous fetoscopic technique for the prenatal closure of large OSB defects. METHODS: Surgery was performed between 24.0 and 28.9 gestational weeks with the woman under general anesthesia, using an entirely percutaneous fetoscopic approach with partial carbon dioxide insufflation of the uterine cavity, as described previously. If there was enough skin to be sutured in the midline, only a biocellulose patch was placed over the placode (single-patch group). In cases in which skin approximation was not possible, a bilaminar skin substitute (two layers: one silicone and one dermal matrix) was placed over the biocellulose patch and sutured to the skin edges (two-patch group). The surgical site was assessed at birth, and long-term follow-up was carried out. RESULTS: Percutaneous fetoscopic OSB repair was attempted in 47 consecutive fetuses, but surgery could not be completed in two. Preterm prelabor rupture of membranes (PPROM) occurred in 36 of the 45 (80%) cases which formed the study group, and the mean gestational age at delivery was 32.8 ± 2.5 weeks. A bilaminar skin substitute was required in 13/45 (29%) cases; in the remaining 32 cases, direct skin-to-skin suture was feasible. There were 12 cases of myeloschisis, of which 10 were in the two-patch group. In all cases, the skin substitute was located at the surgical site at birth. In five of the 13 (38.5%) cases in the two-patch group, additional postnatal repair was needed. In the remaining cases, the silicone layer detached spontaneously from the dermal matrix (on average, 25 days after birth), and the lesion healed by secondary intention. The mean operating time was 193 (range, 83-450) min; it was significantly longer in cases requiring the bilaminar skin substitute (additional 42 min on average), although the two-patch group had similar PPROM rate and gestational age at delivery compared with the single-patch group. Complete reversal of hindbrain herniation occurred in 68% of the 28 single-patch cases and 33% of the 12 two-patch cases with this information available (P < 0.05). In four cases there was no reversal; half of these occurred in myeloschisis cases. CONCLUSIONS: Large OSB defects may be treated successfully in utero using a bilaminar skin substitute over a biocellulose patch through an entirely percutaneous approach. Although the operating time is longer, surgical outcome is similar to that in cases closed primarily. Cases with myeloschisis seem to have a worse prognosis than do those with myelomeningocele. PPROM and preterm birth continue to be a challenge. Further experience is needed to assess the risks and benefits of this technique for the management of large OSB defects. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Subject(s)
Fetoscopy , Neurosurgical Procedures , Postnatal Care/methods , Skin, Artificial , Spina Bifida Cystica/surgery , Female , Fetal Membranes, Premature Rupture , Fetoscopy/methods , Follow-Up Studies , Gestational Age , Humans , Infant, Newborn , Neurosurgical Procedures/methods , Pregnancy , Spina Bifida Cystica/diagnostic imaging , Spina Bifida Cystica/embryology , Time Factors
7.
J Psychosom Res ; 102: 47-53, 2017 11.
Article in English | MEDLINE | ID: mdl-28992897

ABSTRACT

OBJECTIVE: Research has shown that there is an association between Inflammatory Bowel Disease, anxiety and mood disorders, however little is known about their association with Eating Disorders. In this paper we will present a case of a young female with a comorbid diagnosis of Inflammatory Bowel Disease and Eating Disorder, and then discuss the results from a systematic review of the literature, describing published cases of patients with the same condition. METHODS: A systematized review of the literature was conducted according to MOOSE guidelines. A computerized literature search of MEDLINE, PsycINFO and EMBASE, and a manual search through reference lists of selected original articles were performed to identify all published case-reports, case series and studies of Inflammatory Bowel Disease and Eating Disorders. RESULTS: Fourteen articles were included, encompassing 219 cases, including ours. The vast majority were females ranging from 10 to 44years old. Anorexia Nervosa (n=156) and Crohn's Disease (n=129) was the most frequent combination (n=90) reported in the literature. These cases present a poor prognosis because of corticoid refusal, medication abandon and/or deliberate exacerbation of IBD symptoms, in the context of trying to lose weight. CONCLUSION: Recent evidence suggests there is a possible association between Inflammatory Bowel Disease and Eating Disorders, although the mechanisms involved in its ethiopathogenesis are still unknown. To be aware of this association is important because a delayed diagnosis of this comorbidity may lead to worse prognosis. Further research and a multidisciplinary approach could facilitate earlier diagnosis and provide therapeutic interventions.


Subject(s)
Feeding and Eating Disorders , Inflammatory Bowel Diseases , Adolescent , Adult , Child , Comorbidity , Female , Humans , Male , Young Adult
8.
Ultrasound Obstet Gynecol ; 49(5): 573-582, 2017 May.
Article in English | MEDLINE | ID: mdl-27270878

ABSTRACT

OBJECTIVE: To assess the role of first- and early second-trimester markers in the prediction of twin-to-twin transfusion syndrome (TTTS) in monochorionic twin pregnancies. METHODS: Electronic databases MEDLINE, EMBASE and ClinicalTrials.gov were searched from inception to April 2014, using the MeSH term 'fetofetal transfusion' in combination with phrases 'predictive value', 'sensitivity', 'specificity', 'false positive', 'false negative', 'screening', 'accuracy' and 'ROC'. Study quality was assessed using the PRISMA guidelines and QUADAS-2 tool. A meta-analysis was planned for the following predictive factors: intertwin nuchal translucency (NT) discrepancy; NT > 95th percentile in at least one twin; intertwin crown-rump length (CRL) discrepancy as a percentage of the larger CRL; abnormal ductus venosus (DV) flow in at least one twin. The outcome assessed was TTTS, defined according to the presence of a twin oligohydramnios-polyhydramnios sequence. The diagnostic performance of the predictive factors was evaluated for each included study. RESULTS: The electronic search identified 152 records, of which 23 were assessed in full for eligibility. We identified 13 eligible studies that reported the predictive accuracy of ultrasound parameters, measured before 16 weeks, for the development of TTTS, including a total of 1991 pregnancies, of which 323 developed TTTS. An increased risk of TTTS was associated with: intertwin NT discrepancy (positive likelihood ratio (LR+), 1.92 (95% CI, 1.25-2.96); negative likelihood ratio (LR-), 0.65 (95% CI, 0.50-0.84)); NT > 95th percentile (LR+, 2.63 (95% CI, 1.51-4.58); LR-, 0.85 (95% CI, 0.75-0.96)); CRL discrepancy > 10% (LR+, 1.80 (95% CI, 1.05-3.07); LR-, 0.92 (95% CI, 0.81-1.05)); abnormal DV flow (LR+, 4.77 (95% CI, 1.33-17.04; LR-, 0.49 (95% CI, 0.17-1.41)). The highest sensitivities were observed for intertwin NT discrepancy (52.8% (95% CI, 43.8-61.7%)) and abnormal DV flow (50.0% (95% CI, 33.4-66.6%)). CONCLUSION: Monochorionic twin pregnancies with intertwin NT discrepancy, NT > 95th percentile, intertwin CRL discrepancy > 10% or abnormal DV flow on first-trimester ultrasound examination are at significantly increased risk of developing TTTS. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Subject(s)
Fetofetal Transfusion/diagnostic imaging , Ultrasonography, Prenatal , Blood Flow Velocity , Crown-Rump Length , Female , Gestational Age , Humans , Nuchal Translucency Measurement , Pregnancy , Pregnancy Trimester, First , Pregnancy Trimester, Second , Sensitivity and Specificity
10.
Ultrasound Obstet Gynecol ; 45(4): 439-46, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25504904

ABSTRACT

OBJECTIVE: To determine, by expert consensus, the essential substeps of fetoscopic laser surgery (FLS) for twin-twin transfusion syndrome (TTTS) that could be used to create an authority-based curriculum for training in this procedure among fetal medicine specialists. METHODS: A Delphi survey was conducted among an international panel of experts (n = 98) in FLS. Experts rated the substeps of FLS on a five-point Likert-type scale to indicate whether they considered them to be essential, and were able to comment on each substep, using a dedicated online platform accessed by the invited tertiary care facilities that specialize in fetal therapy. Responses were returned to the panel until consensus was reached (Cronbach's α ≥ 0.80). All substeps that were rated ≥ 4 by 80% of the experts were included in the evaluation instrument. RESULTS: After the first iteration of the Delphi procedure, a response rate of 74% (73/98) was reached, and in the second and third iterations response rates of 90% (66/73) and 81% (59/73) were reached, respectively. Among a total of 81 substeps rated in the first round, 21 substeps had to be re-rated in the second round. Finally, from the initial list of substeps, 55 were agreed by experts to be essential. In the third round, the 18 categorized substeps were ranked in order of importance, with 'coagulation of all anastomoses that cross the equator' and 'determination of fetoscope insertion site' as the most important. CONCLUSIONS: A total of 55 substeps of FLS for TTTS were defined by a panel of experts to be essential in the procedure. This list is the first authority-based evidence to be used in the development of a final training model for future fetal surgeons.


Subject(s)
Delphi Technique , Fetofetal Transfusion/surgery , Fetoscopy/methods , Laser Therapy/methods , Computer Simulation , Consensus , Female , Fetoscopy/education , Humans , Pregnancy , Surveys and Questionnaires , Tertiary Care Centers
12.
Radiología (Madr., Ed. impr.) ; 56(1): 7-15, ene.-feb. 2014. tab, ilus
Article in Spanish | IBECS | ID: ibc-118515

ABSTRACT

La sacroileítis radiográfica ha formado parte del diagnóstico de las espondiloartropatías desde su inclusión en los criterios de Roma en 1961. Sin embargo, en la última década, la resonancia magnética (RM) ha demostrado ser más sensible para valorar las articulaciones sacroilíacas en los pacientes con sospecha de espondiloartritis y síntomas de sacroileítis, no solo para diagnosticarla, sino también para seguir la evolución de la enfermedad y el tratamiento de estos pacientes. El grupo The Assessment of SpondyloArthritis international Society (ASAS) desarrolló en el año 2009 unos criterios para clasificar y diagnosticar a los pacientes con espondiloartritis, entre los que destacaba la inclusión de un estudio de RM positivo para sacroileítis como criterio diagnóstico mayor. Este artículo incide en la parte radiológica de esta clasificación. Se describen e ilustran las diferentes alteraciones que podemos encontrarnos en los estudios de RM en pacientes con sacroileítis, resaltando las limitaciones y potenciales errores diagnósticos (AU)


Radiographic sacroiliitis has been included in the diagnostic criteria for spondyloarthropathies since the Rome criteria were defined in 1961. However, in the last ten years, magnetic resonance imaging (MRI) has proven more sensitive in the evaluation of the sacroiliac joints in patients with suspected spondyloarthritis and symptoms of sacroiliitis; MRI has proven its usefulness not only for diagnosis of this disease, but also for the follow-up of the disease and response to treatment in these patients. In 2009, The Assessment of SpondyloArthritis international Society (ASAS) developed a new set of criteria for classifying and diagnosing patients with spondyloarthritis; one important development with respect to previous classifications is the inclusion of MRI positive for sacroiliitis as a major diagnostic criterion. This article focuses on the radiologic part of the new classification. We describe and illustrate the different alterations that can be seen on MRI in patients with sacroiliitis, pointing out the limitations of the technique and diagnostic pitfalls (AU)


Subject(s)
Humans , Male , Female , Spondylarthritis , Sacroiliitis , Magnetic Resonance Imaging/instrumentation , Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy/methods , Diagnosis, Differential , Arthropathy, Neurogenic , Tomography, Emission-Computed/instrumentation , Tomography, Emission-Computed/methods , Magnetic Resonance Spectroscopy/classification , Fibrous Dysplasia of Bone , Osteitis , Synovitis
13.
Radiologia ; 56(1): 7-15, 2014.
Article in Spanish | MEDLINE | ID: mdl-24119715

ABSTRACT

Radiographic sacroiliitis has been included in the diagnostic criteria for spondyloarthropathies since the Rome criteria were defined in 1961. However, in the last ten years, magnetic resonance imaging (MRI) has proven more sensitive in the evaluation of the sacroiliac joints in patients with suspected spondyloarthritis and symptoms of sacroiliitis; MRI has proven its usefulness not only for diagnosis of this disease, but also for the follow-up of the disease and response to treatment in these patients. In 2009, The Assessment of SpondyloArthritis international Society (ASAS) developed a new set of criteria for classifying and diagnosing patients with spondyloarthritis; one important development with respect to previous classifications is the inclusion of MRI positive for sacroiliitis as a major diagnostic criterion. This article focuses on the radiologic part of the new classification. We describe and illustrate the different alterations that can be seen on MRI in patients with sacroiliitis, pointing out the limitations of the technique and diagnostic pitfalls.


Subject(s)
Magnetic Resonance Imaging , Sacroiliitis/diagnosis , Spondylarthritis/diagnosis , Humans , Practice Guidelines as Topic , Sacroiliitis/classification
14.
Article in English | MEDLINE | ID: mdl-24229280

ABSTRACT

Radiation of energy by large-amplitude leaky Rayleigh waves is regarded as one of the key physical mechanisms regulating the actuation and manipulation of droplets in surface acoustic wave (SAW) microfluidic devices. The interaction between a SAW and a droplet is highly complex and is presently the subject of extensive research. This paper investigates the existence of an additional interaction mechanism based on the propagation of quasi-Stoneley waves inside sessile droplets deposited on a solid substrate. In contrast with the leaky Rayleigh wave, the energy of the Stoneley wave is confined within a thin fluid layer in contact with the substrate. The hypothesis is confirmed by three-dimensional finite element simulations and ultrasonic scattering experiments measuring the reflection of Rayleigh waves from droplets of different diameters. Moreover, real-time monitoring of the droplet evaporation process reveals a clear correlation between the droplet contact angle and the spectral information of the reflected Rayleigh signal, thus paving the way for ultrasonic measurements of surface tension.

15.
J Chem Phys ; 139(17): 174307, 2013 Nov 07.
Article in English | MEDLINE | ID: mdl-24206298

ABSTRACT

We present pseudo-potential density functional theory calculations dedicated to analyze the stability and electronic properties of thiol-based molecular overlayers adsorbed on C60. We consider short molecules having a S atom as a headgroup, alkyl chains containing one to three C atoms, and a CH3 species as a terminal group. The thiol molecules are bonded to the carbon surface (through the S atom) with adsorption energies that vary in the range of ~1-2 eV and with S-C bond lengths of ~1.8 Å. For neutral C60(SCH3)n complexes, low energy atomic configurations are obtained when the thiol groups are distributed on the surface forming small molecular domains (e.g., pairs, trimers, or tetramer configurations of neighboring thiol molecules). In contrast, less stable random distributions are defined by orientationally disordered overlayers with highly distorted underlying carbon networks. The inclusion of London dispersion interaction slightly affects the structure of the molecular coating but increases the adsorption energies by values as large as 0.3 eV. Interestingly, the relative stability of the previous adsorbed phases differ from the one obtained when considering single sulfur adsorption on C60, a result that reveals the crucial role played by the terminal CH3 groups on the structure of the molecular coating. The positive (negative) charging of the [C60(SCH3)n](±q) complexes, with q as large as 8e, changes the geometrical structure and the chemical nature of the ligand shell inducing lateral molecular displacements, S-S bonding between neighboring thiols, as well as the partial degradation of the molecular coating. Finally, we consider the stability of two-component mixed overlayers formed by the coadsorption of CH3-, OH-, and NH2-terminated alkanethiols of the same length. In agreement with the results found on Au surfaces, we obtain lowest energy atomic configurations when molecular domains of a single component are stabilized on C60, a result that could be of fundamental importance in biomedical applications.

16.
ScientificWorldJournal ; 2013: 723645, 2013.
Article in English | MEDLINE | ID: mdl-23997679

ABSTRACT

This paper reports a solution for trajectory tracking control of a differential drive wheeled mobile robot (WMR) based on a hierarchical approach. The general design and construction of the WMR are described. The hierarchical controller proposed has two components: a high-level control and a low-level control. The high-level control law is based on an input-output linearization scheme for the robot kinematic model, which provides the desired angular velocity profiles that the WMR has to track in order to achieve the desired position (x∗, y∗) and orientation (φ∗). Then, a low-level control law, based on a proportional integral (PI) approach, is designed to control the velocity of the WMR wheels to ensure those tracking features. Regarding the trajectories, this paper provides the solution or the following cases: (1) time-varying parametric trajectories such as straight lines and parabolas and (2) smooth curves fitted by cubic splines which are generated by the desired data points {(x1∗, y1∗),..., (x(n)∗, y(n)∗)}. A straightforward algorithm is developed for constructing the cubic splines. Finally, this paper includes an experimental validation of the proposed technique by employing a DS1104 dSPACE electronic board along with MATLAB/Simulink software.


Subject(s)
Robotics , Biomechanical Phenomena , Models, Theoretical
17.
Med. intensiva (Madr., Ed. impr.) ; 34(8): 550-558, nov. 2010. ilus
Article in Spanish | IBECS | ID: ibc-95152

ABSTRACT

Durante la resucitación cardiopulmonar y tras la recuperación de la circulación espontánea, una perfusión tisular efectiva determina el pronóstico final. La ultranosografía Doppler transcraneal (DTC) registra la velocidad y la pulsatilidad del flujo sanguíneo cerebral y permite realizar análisis hemodinámicos «latido a latido». Durante la resucitación cardiopulmonar la velocidad sistólica máxima alcanzada refleja la perfusión cerebral en cada compresión torácica. Tras la recuperación de la circulación espontánea, la persistencia después de 2h de un patrón arterial cerebral hipodinámico (baja velocidad media y alta pulsatilidad en la DTC) pronostica mala recuperación neurológica. La presencia, precoz o tardía, de un patrón de DTC hiperémico (alta velocidad media y baja pulsatilidad) se asocia a mal pronóstico por evolución a hipertensión intracraneal; su aparición durante la fase de recalentamiento debería llevar a reinstaurar la hipotermia terapéutica La coincidencia de arterias con patrones hipodinámicos con otras normales o hiperdinámicas indica focos de hipoperfusión que son predictores de ictus (AU)


An effective tissue perfusion has decisive influence on the final prognosis both during cardiopulmonary resuscitation (CPR) and after recovery of spontaneous circulation (ROSC). The transcranial Doppler ultranosography (TCD) examines the velocity and pulsatility of cerebral blood flow, making it possible to perform "beat to beat" hemodynamic analysis. During CPR, TCD peak systolic velocity reflects cerebral perfusion of the chest compressions. Beyond 2 hours after ROSC, persistence in the cerebral arteries of a hemodynamic TCD pattern (low velocities with high pulsatilities) predicts poor neurological prognosis. Early or delayed presence of a hyperemic TCD pattern (high velocities with low pulsatilities) is associated conclusively with evolution to intracranial hypertension and its appearance during the rewarming process should lead to immediate return to therapeutic hypothermia. The coincidence of hypodynamic cerebral arteries and others with normal or hyperemic TCD patterns may indicate the presence of focal hypoperfusion that could predict stroke after ROSC (AU)


Subject(s)
Humans , Ultrasonography, Doppler, Transcranial/methods , Cardiopulmonary Resuscitation/methods , Heart Arrest/therapy , Stroke/prevention & control , Prehospital Care , Hemodynamics
19.
Med Intensiva ; 34(8): 550-8, 2010 Nov.
Article in Spanish | MEDLINE | ID: mdl-20211509

ABSTRACT

An effective tissue perfusion has decisive influence on the final prognosis both during cardiopulmonary resuscitation (CPR) and after recovery of spontaneous circulation (ROSC). The transcranial Doppler ultranosography (TCD) examines the velocity and pulsatility of cerebral blood flow, making it possible to perform "beat to beat" hemodynamic analysis. During CPR, TCD peak systolic velocity reflects cerebral perfusion of the chest compressions. Beyond 2 hours after ROSC, persistence in the cerebral arteries of a hemodynamic TCD pattern (low velocities with high pulsatilities) predicts poor neurological prognosis. Early or delayed presence of a hyperemic TCD pattern (high velocities with low pulsatilities) is associated conclusively with evolution to intracranial hypertension and its appearance during the rewarming process should lead to immediate return to therapeutic hypothermia. The coincidence of hypodynamic cerebral arteries and others with normal or hyperemic TCD patterns may indicate the presence of focal hypoperfusion that could predict stroke after ROSC.


Subject(s)
Cardiopulmonary Resuscitation/methods , Cerebrovascular Circulation , Heart Arrest/therapy , Hypoxia-Ischemia, Brain/diagnostic imaging , Ultrasonography, Doppler, Transcranial , Brain Damage, Chronic/diagnostic imaging , Brain Damage, Chronic/physiopathology , Brain Damage, Chronic/prevention & control , Coma/etiology , Critical Care/methods , Heart Arrest/complications , Heart Massage , Humans , Hypoxia-Ischemia, Brain/etiology , Hypoxia-Ischemia, Brain/physiopathology , Pulsatile Flow , Systole , Time Factors
20.
Childs Nerv Syst ; 25(9): 1137-41, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19415299

ABSTRACT

INTRODUCTION: Bites by house pets can be lethal or cause a series of catastrophic events with severe sequels, such as the loss of a limb or a systemic infection which may be life-endangering, especially in the case of children being bitten. PRESENTATION: A 2-year-old girl was attacked by a dog, causing lesions at the occipital region. This was treated initially as a superficial wound that became further complicated with two cerebellar abscesses. These abscesses required neurosurgical and antimicrobial treatment, with a satisfactory outcome. CONCLUSION: The precise and diligent evaluation of a lesion caused by an animal bite may prevent further life-endangering complications. To the best of our knowledge, there are no reports about cerebellar abscess caused by a dog bite. When cranial lesions are penetrating, an abscess must to be considered. We insist on the importance of medical evaluation and adequate treatment of such lesions.


Subject(s)
Bites and Stings/complications , Brain Abscess/etiology , Cerebellar Diseases/etiology , Dogs , Animals , Brain Abscess/pathology , Brain Abscess/therapy , Cerebellar Diseases/pathology , Cerebellar Diseases/therapy , Child, Preschool , Female , Humans , Magnetic Resonance Imaging , Skull Fractures/etiology , Skull Fractures/pathology , Skull Fractures/therapy , Tomography, X-Ray Computed , Treatment Outcome
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