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1.
J Phys Condens Matter ; 36(14)2024 Jan 04.
Article in English | MEDLINE | ID: mdl-38086082

ABSTRACT

The emerging two-dimensional (2D) semiconductors substantially extend materials bases for versatile applications such as semiconductor photocatalysis demanding semiconductive matrices and large surface areas. The dimensionality, while endowing 2D semiconductors the unique properties to host photocatalytic functionality of pollutant removal and hydrogen evolution, hurdles the activation paths to form heterogenous photocatalysts where the photochemical processes are normally superior over these on the mono-compositional counterparts. In this perspective, we present a cross-dimensional strategy to employ thenD (n= 0-2) clusters or nanomaterials as activation partners to boost the photocatalytic activities of the 2D semiconductors. The formation principles of heterogenous photocatalysts are illustrated specifically for the 2D matrices, followed by selection criteria of them among the vast 2D database. The computer investigations are illustrated in the density functional theory route and machine learning benefitted from the vast samples in the 2D library. Synthetic realizations and characterizations of the 2D heterogenous systems are introduced with an emphasis on chemical methods and advanced techniques to understand materials and mechanistic studies. The perspective outlooks cross-dimensional activation strategies of the 2D materials for other applications such as CO2removal, and materials matrices in other dimensions which may inspire incoming research within these fields.

2.
Actas Urol Esp (Engl Ed) ; 47(10): 681-687, 2023 Dec.
Article in English, Spanish | MEDLINE | ID: mdl-37355205

ABSTRACT

INTRODUCTION: The vacuum-assisted access sheath is a new device for the treatment of kidney stones with percutaneous nephrolithotomy (PCNL). OBJECTIVE: Our aim was to compare the stone-free rate (SFR) and complications between standard mini percutaneous nephrolithotomy (Mini-PCNL) and vacuum-assisted PCNL (Va-PCNL). METHODS: Retrospective study of patients undergoing Mini-PCNL and Va-PCNL from January 2018 to June 2022. Va-PCNL was performed with a disposable sheath (ClearPetra®) with continuous high-flow irrigation and vacuum fluid dynamics for easier stone fragment removal. Baseline patient characteristics, surgical outcomes, perioperative and postoperative data were collected. We compared SFR and complications. RESULTS: A total of 136 patients were identified, 57 (41,9%) underwent Va-PCNL and 79 (58,15%) Mini-PCNL. Mean operative time was significantly shorter in the Va-PCNL group (95 min.) than in Mini-PCNL (146 min; P = ,001) group. The tubeless technique was performed more frequently in Va-PCNL group (61,4% vs. 34,2%; P = ,002). We did not observe any differences in postoperative complications. The mean hospital stay was significantly lower in Va-PCNL with 1,7 ± 1,9 days per patient compared with 2,7 ± 1,5 days in the Mini-PCNL group (P = ,001). There were no differences in SFR at 3 months between Va-PCNL (71,9%) and Mini-PCNL (71,8%; P =v ,848). CONCLUSION: Patients treated with Va-PCNL had comparable results to Mini-PCNL, showing equal SFR with similar infectious complications rates. Potential benefits of Va-PCNL include shorter operative time and postoperative stay.


Subject(s)
Kidney Calculi , Nephrolithotomy, Percutaneous , Humans , Nephrolithotomy, Percutaneous/adverse effects , Retrospective Studies , Treatment Outcome , Kidney Calculi/etiology , Postoperative Complications/epidemiology , Postoperative Complications/etiology
3.
Int J Surg Open ; 26: 30-35, 2020.
Article in English | MEDLINE | ID: mdl-34568610

ABSTRACT

BACKGROUND: In the oncological patient, an COVID-19-Infection, whether symptomatic or asymptomatic, a surgical procedure may carry a higher postoperative morbidity and mortality. The aim of this study was to describe the impact on clinical practice of sequential preoperative screening for COVID-19-infection in deciding whether to proceed or postpone surgery. METHODS: Prospective, cohort study, based on consecutive patients' candidates for an oncological surgical intervention. Sequential preoperative screening for COVID-19-infection: two-time medical history (telematic and face-to-face), PCR and chest CT, 48 h before of surgical intervention. COVID-19-infection was considered positive if the patient had a suggestive medical history and/or PCR-positive and/or CT of pneumonia. RESULTS: Between April 15th and May 4th, 2020, 179 patients were studied, 97 were male (54%), mean (sd) age 66.7 (13,6). Sequential preoperative screening was performed within 48 h before to surgical intervention. The prevalence of preoperative COVID-19-infection was 4.5%, 95%CI:2.3-8.6% (8 patients). Of the operated patients (171), all had a negative medical history, PCR and chest CT. The complications was 14.8% (I-II) and 2.5% (III-IV). There was no mortality. The hospital stay was 3.1 (sd 2.7) days.In the 8 patients with COVID-19-infection, the medical history was suggestive in all of them, 7 presented PCR-positive and 5 had a chest CT suggestive of pneumonia. The surgical intervention was postponed between 15 and 21 days. CONCLUSION: Preoperative screening for COVID-19-infection using medical history and PCR helped the surgeon to decide whether to go ahead or postpone surgery in oncological patients. The chest CT may be useful in unclear cases.

4.
Article in English, Spanish | MEDLINE | ID: mdl-30173729

ABSTRACT

PURPOSE: Complications related to anterior cruciate ligament (ACL) graft are common. Change in height, especially patella baja, can be a cause of anterior knee pain. Several studies have related ACL reconstruction with bone-tendon-bone graft to patella baja. METHODS: Forty-three patients with ACL reconstruction using a with bone-tendon-bone graft were included in this study. All patients underwent the same surgery, with closure of the paratenon of the patellar tendon. A radiological study was performed before surgery and 2 years after surgery. The Insall-Salvati index, axial view and patellar tilt were analyzed in all patients. The healthy contralateral knees were used as the control group. RESULTS: No significant differences were observed from the preoperative measurements or at the 2-year follow-up. CONCLUSIONS: The use of patellar tendon with closure of the paratenon in ACL reconstruction was not shown to modify patellar height within the radiological follow-up of two years.


Subject(s)
Anterior Cruciate Ligament Injuries/surgery , Bone-Patellar Tendon-Bone Grafting/adverse effects , Patella/pathology , Postoperative Complications/etiology , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Male , Middle Aged , Patella/diagnostic imaging , Patella/surgery , Postoperative Complications/diagnostic imaging , Postoperative Complications/pathology , Prospective Studies , Radiography , Treatment Outcome
6.
Eye (Lond) ; 30(6): 833-42, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27034202

ABSTRACT

AimsThe aim of this study was to compare transscleral resection technique performed without hypotensive anaesthesia (TSRWH) with iodine-125 brachytherapy (IBT) in the treatment of choroidal melanoma.Patients and methodsThis was a retrospective surgical cohort study. Nineteen eyes treated with TSRWH were matched with 53 eyes treated with IBT according to: tumour size, distance to fovea, distance to optic nerve, and follow-up time. Best-corrected visual acuity (BCVA), local recurrence, secondary enucleation, metastasis, overall and specific survival, and complications were evaluated.ResultsPatients treated with TSRWH had significantly better BCVA than those treated with IBT. The local recurrence risk was significantly higher when ciliary body was involved (HR=11.4, 95% CI 2.24-49.7, P=0.04). Metastatic disease was observed in 14 of 53 patients (26.4%) in the IBT group vs 3 patients (15.8%) in the TSRWH group (P=0.531). Multivariate analysis showed that iris involvement (HR=16.0, 95% CI 4.2-170.2, P=0.033) and large tumour (HR=2.3, 95% CI 1.2-4.8, P=0.04) increased the probability of metastasis. During follow-up, six patients (11.3%) in IBT group died vs two (10.5%) in the TSRWH group (P≥0.999). Nine patients required secondary enucleation: 5 (9.4%) in the IBT group vs 4 (21.1%) in the TSRWH group (P=0.231). The most common complications in IBT group were radiation-induced retinopathy (45.3%), neovascular glaucoma (28.3%), and macular oedema (24.5%), whereas rhegmatogenous retinal detachment (21.1%), ocular hypertension (21.1%), and submacular haemorrhage (15.8%) were the most frequent complications after TSRWH.ConclusionTSRWH is a technically challenging procedure. However, when performed successfully, this technique achieves better preservation of visual acuity than IBT and without the limitations inherent in hypotensive anaesthesia.


Subject(s)
Brachytherapy/methods , Choroid Neoplasms/therapy , Iodine Radioisotopes/therapeutic use , Melanoma/therapy , Ophthalmologic Surgical Procedures , Adult , Aged , Aged, 80 and over , Anesthesia, Inhalation , Choroid Neoplasms/pathology , Choroid Neoplasms/radiotherapy , Choroid Neoplasms/surgery , Female , Humans , Lens Implantation, Intraocular , Male , Melanoma/pathology , Melanoma/radiotherapy , Melanoma/surgery , Middle Aged , Phacoemulsification , Retrospective Studies , Sclera/surgery , Visual Acuity
7.
Chem Commun (Camb) ; 51(75): 14191-4, 2015 Sep 28.
Article in English | MEDLINE | ID: mdl-26256926

ABSTRACT

One of the main concerns in the technological application of several metal-organic frameworks (MOFs) relates to their structural instability under pressure (after a conforming step). Here we report for the first time that mechanical instability can be highly improved via nucleation and growth of MOF nanocrystals in the confined nanospace of activated carbons.


Subject(s)
Carbon/chemistry , Nanoparticles/chemistry , Organometallic Compounds/chemistry , Metal-Organic Frameworks , Molecular Structure
8.
Acta Ortop Mex ; 27(4): 246-9, 2013.
Article in Spanish | MEDLINE | ID: mdl-24707614

ABSTRACT

Intraarticular ganglions are rare and they are usually incidental findings of MRIs and arthroscopies. We report the case of a male athlete with this condition affecting the anterior cruciate ligament. The most frequent symptoms include pain that worsens with activity, and motion limitations. The MRI shows the typical signs of a ganglion and it is the most specific and sensitive test. Arthroscopy is used for both the diagnosis and the treatment of this condition. A late diagnosis turns arthroscopic resection into a complicated or impossible procedure that at times warrants extensive debridement of the anterior cruzate ligament.


Subject(s)
Anterior Cruciate Ligament , Ganglion Cysts , Adolescent , Ganglion Cysts/diagnosis , Ganglion Cysts/surgery , Humans , Male
9.
Langmuir ; 28(10): 4815-28, 2012 Mar 13.
Article in English | MEDLINE | ID: mdl-22332777

ABSTRACT

The binding of cationic surfactants with varying alkyl chain length to a regiorandom conjugated polyanion, poly(3-thiophene acetic acid) (PTAA), is studied in an aqueous buffer by using absorption and emission spectroscopies, photon correlation spectroscopy, isothermal titration calorimetry, and cryogenic transmission electron microscopy. We study the mixed solutions as a function of composition ratio R of surfactant molecules to monomer units molar concentrations, at low polymer concentration and in a very wide composition range (10(-6) < R < 10(2)) below the critical micellar concentration. Upon surfactant binding, the molecularly dispersed chains first collapse progressively and then form new structures as the mixed aggregates get enriched in surfactant. The collapse leads to a strong decrease of the conjugation length and to a blue shift of the absorption spectra by 30 to 50 nm. The new structures are responsible for a new intense emission band at about 600 nm, red-shifted by nearly 130 nm from the initial emission maximum of the polymer (~472 nm). As the surfactant tail becomes shorter, the blue shift of the absorption spectra and the intensity raise of the new emission are delayed to larger composition ratios while their variations become smoother functions of the surfactant concentration. These particular spectroscopic properties of PTAA seem related to its unique combination of a strongly hydrophobic backbone, a large ratio of contour length to persistence length, and an overall good aqueous solubility. Our results show that such features are well suited to design a colorimetric biosensor at small composition ratio, and a fluorescent biomarker at large composition ratio.


Subject(s)
Acetates/chemistry , Biosensing Techniques , Surface-Active Agents/chemistry , Thiophenes/chemistry , Trimethyl Ammonium Compounds/chemistry , Biophysical Phenomena , Calorimetry , Cryoelectron Microscopy , Hydrodynamics , Macromolecular Substances/chemistry , Molecular Structure , Quaternary Ammonium Compounds/chemistry , Spectrum Analysis , Thermodynamics
10.
Acta Ortop Mex ; 26(2): 121-4, 2012.
Article in Spanish | MEDLINE | ID: mdl-23323303

ABSTRACT

INTRODUCTION: Anterior tibial tubercle fractures are relatively infrequent and occur mainly in young athletes 14 to 17 years old. Most fractures result from jumping during sports activities. METHODS: We describe two cases of anterior tibial tubercle fractures. The latter were Ogden IIIA and IIIB. In both cases treatment consisted of open reduction and internal fixation with cannulated screws. DISCUSSION: The mechanism of injury in the first case is more common than the one in the second case. The first case occurred after jumping to receive a pass during a basketball game. The second one occurred while playing soccer. The patient was kicked on the quadriceps musculature. Both cases involved functional disability. CONCLUSION: Biomechanically, the mechanism of injury in the second case increased the tension on the extensor apparatus. We performed synthesis with cannulated screws and obtained good results without complications.


Subject(s)
Tibial Fractures , Adolescent , Humans , Male , Radiography , Tibial Fractures/diagnostic imaging , Tibial Fractures/surgery
12.
An Med Interna ; 24(4): 177-8, 2007 Apr.
Article in Spanish | MEDLINE | ID: mdl-17867901

ABSTRACT

We present a case of systemic lupus erythematosus complicated by pancytopenia and visceral leishmaniasis in Spain. The literature on opportunistic infection in lupus erythematosus is reviewed.Leishmaniasis is a group of infections caused by the protozoa Leishmania, which is endemic in the Mediterranean basin. These opportunistic infections are an emerging entity in immunosuppressed patients. The use of immunosuppressive treatment in systemic lupus erythematosus modifies natural defense patterns and increases the risk of visceral leishmaniasis in endemic areas.


Subject(s)
Leishmaniasis, Visceral/etiology , Lupus Erythematosus, Systemic/complications , Adult , Amphotericin B/administration & dosage , Amphotericin B/therapeutic use , Antiprotozoal Agents/administration & dosage , Antiprotozoal Agents/therapeutic use , Female , Follow-Up Studies , Humans , Immunosuppression Therapy/adverse effects , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/drug therapy , Lupus Erythematosus, Systemic/drug therapy , Lupus Erythematosus, Systemic/immunology , Pancytopenia/etiology , Time Factors
13.
Phys Rev Lett ; 96(18): 181801, 2006 May 12.
Article in English | MEDLINE | ID: mdl-16712358

ABSTRACT

We performed an improved search for nu(mu) --> nu(e) oscillation with the KEK to Kamioka (K2K) long-baseline neutrino oscillation experiment, using the full data sample of 9.2 x 10(19) protons on target. No evidence for a nu(e) appearance signal was found, and we set bounds on the nu(mu) --> nu(e) oscillation parameters. At Deltam(2)=2.8 x 10(-3) eV(2), the best-fit value of the K2Knu(mu) disappearance analysis, we set an upper limit of sin(2)2theta(mue) < 0.13 at a 90% confidence level.

15.
Neuroscience ; 133(1): 137-45, 2005.
Article in English | MEDLINE | ID: mdl-15893637

ABSTRACT

The number and distribution of spines along apical shafts of rapid-Golgi-stained layer V pyramidal cells from visual, motor and somatosensory cortical areas were analyzed in control and movement-restricted (beginning at 20 days old) Wistar rats killed at 30, 40, 80 and 120 days of age (experiment A). In other group of rats, spine density was analyzed when restriction initiates on day 40 and the animals were killed at 50, 60 and 80 days postpartum, or after restriction starting on day 80 and killed at 120 days of age (experiment B). It has been found that the restriction of movements significantly reduces the total number of spines on apical shafts in the three cortical areas, when this condition starts at 20, 40 or 80 days without changing the overall distribution of spines. Also present findings indicate that the effects of movements restriction are attenuated when they were concurrent with maturational brain processes (20-40 days) than when they occurred later in life. The question remains open of which part of the measured reduction on the number of spines is due to the immobilization and which to the stress associated with this maneuver.


Subject(s)
Aging/physiology , Immobilization , Motor Cortex/physiology , Motor Cortex/ultrastructure , Neurites/physiology , Pyramidal Cells/physiology , Pyramidal Cells/ultrastructure , Somatosensory Cortex/physiology , Somatosensory Cortex/ultrastructure , Animals , Body Weight/physiology , Image Processing, Computer-Assisted , Male , Rats , Rats, Wistar , Sexual Maturation , Stress, Psychological/pathology , Visual Cortex/physiology , Visual Cortex/ultrastructure
19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 66(3 Pt 1): 031403, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12366113

ABSTRACT

We study the relaxation for growing interfaces in quenched disordered media. We use a directed percolation depinning model introduced by Tang and Leschhorn for 1+1 dimensions. We define the two-time autocorrelation function of the interface height C(t('),t) and its Fourier transform. These functions depend on the difference of times t-t(') for long enough times, this is the steady-state regime. We find a two-step relaxation decay in this regime. The long time tail can be fitted by a stretched exponential relaxation function. The relaxation time tau(alpha) is proportional to the characteristic distance of the clusters of pinning cells in the direction parallel to the interface and it diverges as a power law. The two-step relaxation is lost at a given wavelength of the Fourier transform, which is proportional to the characteristic distance of the clusters of pinning cells in the direction perpendicular to the interface. The stretched exponential relaxation is caused by the existence of clusters of pinning cells and it is a direct consequence of the quenched noise.

20.
Int J Exp Diabetes Res ; 2(2): 101-12, 2001.
Article in English | MEDLINE | ID: mdl-12369713

ABSTRACT

Plasma levels of glucose, insulin and glucagon were measured at various time intervals after pancreatic duct ligation (PDL) in rabbits. Two hyperglycemic periods were observed: one between 15-90 days (peak at 30 days of 15.1 +/- 1.2 mmol/l, p < 0.01), and the other at 450 days (11.2 +/- 0.5 mmol/l, p < 0.02). The first hyperglycemic episode was significantly correlated with both hypoinsulinemia (41.8 +/- 8 pmol/l, r = -0.94, p < 0.01) and hyperglucagonemia (232 +/- 21 ng/l, r = 0.95, p < 0.01). However, the late hyperglycemic phase (450 days), which was not accompanied by hypoinsulinemia, was observed after the hyperglucagonemia (390 days) produced by abundant immunostained A-cells giving rise to a 3-fold increase in pancreatic glucagon stores. The insulin and glucagon responses to glucose loading at 180, 270 and 450 days reflected the insensitivity of B- and A-cells to glucose. The PDL rabbit model with chronic and severe glycemic disorders due to the predominant role of glucagon mimicked key features of the NIDDM syndrome secondary to exocrine disease.


Subject(s)
Blood Glucose/metabolism , Diabetes Mellitus, Type 2/blood , Glucagon/blood , Insulin/blood , Islets of Langerhans/metabolism , Pancreatic Ducts/physiology , Animals , Diabetes Mellitus, Type 2/pathology , Disease Models, Animal , Islets of Langerhans/pathology , Male , Rabbits , Time Factors
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