Adsorption-Induced Solvent-Based Electrostatic Gating of Charge Transport through Molecular Junctions.

Recent experiments have shown that transport properties of molecular-scale devices can be reversibly altered by the surrounding solvent. Here, we use a combination of first-principles calculations and experiment to explain this change in transport properties through a shift in the local electrostatic potential at the junction caused by nearby conducting and solvent molecules chemically bound to the electrodes. This effect is found to alter the conductance of 4,4'-bipyridine-gold junctions by more than 50%. Moreover, we develop a general electrostatic model that quantitatively relates the conductance and dipoles associated with the bound solvent and conducting molecules. Our work shows that solvent-induced effects can be used to control charge and energy transport at molecular-scale interfaces.

Effect of metal complexation on the conductance of single-molecular wires measured at room temperature.

The present work aims to give insight into the effect that metal coordination has on the room-temperature conductance of molecular wires. For that purpose, we have designed a family of rigid, highly conductive ligands functionalized with different terminations (acetylthiols, pyridines, and ethynyl groups), in which the conformational changes induced by metal coordination are negligible. The single-molecule conductance features of this series of molecular wires and their corresponding Cu(I) complexes have been measured in break-junction setups at room temperature. Experimental and theoretical data show that no matter the anchoring group, in all cases metal coordination leads to a shift toward lower energies of the ligand energy levels and a reduction of the HOMO-LUMO gap. However, electron-transport measurements carried out at room temperature revealed a variable metal coordination effect depending on the anchoring group: upon metal coordination, the molecular conductance of thiol and ethynyl derivatives decreased, whereas that of pyridine derivatives increased. These differences reside on the molecular levels implied in the conduction. According to quantum-mechanical calculations based on density functional theory methods, the ligand frontier orbital lying closer to the Fermi energy of the leads differs depending on the anchoring group. Thereby, the effect of metal coordination on molecular conductance observed for each anchoring could be explained in terms of the different energy alignments of the molecular orbitals within the gold Fermi level.

[Diagnosis and prognosis of fetal ebstein anomaly]. / Diagnóstico y pronóstico fetales de la anomalía de Ebstein.

BACKGROUND: Fetal echocardiography is possible to confirm with great certainty the diagnosis, in utero, Ebstein's anomaly, as well as determine its perinatal prognosis. OBJECTIVE: Review the experience of 16 cases diagnosed with Ebstein's anomaly, using fetal echocardiography, analyzing "forecast echocardiographic parameters" set by Pavlova, Huhta and Barre. MATERIAL AND METHOD: retrospective and descriptive analysis. We analysed echocardiographic parameters and its correlation with the perinatal development of 16 cases diagnosed with Ebstein's anomaly. RESULTS: Maternal age of our patients was 27.94 +/- 5.7 years, gestational age 31.3 +/- 3.6.) Mortality: in-utero 37.5% (n = 6), neonatal 50% (n = 8), survived 12.5% (n = 2). Cardiothoracic index 0.61 +/- 0.074, relationship foramen oval/heart atrial 0.6 +/- 0.015; obstruction to the way out of the right ventricle in 14 cases (87.5%). The deceased 81% presented degree of valvular displacement > 2.5; relationship RV/LV 2.24 +/- 0.37). CONCLUSIONS: Cardiothoracic index fetal stage > 0.55, relationship oval foramen/interatrial septum < 0.3, obstruction to the way out and a degree of valvular displacement > 2.5, absence of back flow in arteriosus ductus and a ratio RV/LV > 2 are poor prognostic factors for Ebstein's anomaly.

Protein Biomarkers in Lung Cancer Screening: Technical Considerations and Feasibility Assessment.

Lung cancer remains the leading cause of cancer-related deaths worldwide, mainly due to late diagnosis and the presence of metastases. Several countries around the world have adopted nation-wide LDCT-based lung cancer screening that will benefit patients, shifting the stage at diagnosis to earlier stages with more therapeutic options. Biomarkers can help to optimize the screening process, as well as refine the TNM stratification of lung cancer patients, providing information regarding prognostics and recommending management strategies. Moreover, novel adjuvant strategies will clearly benefit from previous knowledge of the potential aggressiveness and biological traits of a given early-stage surgically resected tumor. This review focuses on proteins as promising biomarkers in the context of lung cancer screening. Despite great efforts, there are still no successful examples of biomarkers in lung cancer that have reached the clinics to be used in early detection and early management. Thus, the field of biomarkers in early lung cancer remains an evident unmet need. A more specific objective of this review is to present an up-to-date technical assessment of the potential use of protein biomarkers in early lung cancer detection and management. We provide an overview regarding the benefits, challenges, pitfalls and constraints in the development process of protein-based biomarkers. Additionally, we examine how a number of emerging protein analytical technologies may contribute to the optimization of novel robust biomarkers for screening and effective management of lung cancer.

[Fetal diagnosis and prognosis of Ebstein's anomaly]. / Diagnóstico y pronóstico fetal de la anomalía de Ebstein.

BACKGROUND: Currently fetal echocardiography may confirm the diagnosis in utero of Ebstein anomaly, as well as determine the perinatal outcome with high certainty. OBJECTIVE: To review 16 cases diagnosed with Ebstein anomaly, by fetal echocardiography, analyzing prognostic echocardiographic parameters set by Pavlova and colleagues. MATERIAL AND METHOD: A descriptive, observational, retrospective study was done in patients with fetal diagnosis of Ebstein anomaly, during January 2001 to December 2011. Echocardiographic parameters are analyzed and its correlation to perinatal evolution of 16 cases of Ebstein anomaly. RESULTS: Maternal age was of 27.94 + 5.7 years, gestational age was 31.3 +/- 3.6 weeks. In utero mortality represented 37.5% (n = 6), and neonatal mortality 50% (n = 8), two patients (12.5%) survived. Cardiothoracic index was of 0.61 +/- 0.074, ratio foramen ovale-atrial septal was of 0.6 +/- 0.015, obstruction of the outflow tract of the right ventricle was seen in 14 (87.5%) patients; 81% of the deceased had a degree of displacement valve > 2.5; ratio right ventricle-left ventricle 2.24 +/- 0.37. The umbilical vein was throbbing in 64% of the deceased, the tricuspid insufficiency was severe in 15 cases (94%, 21.62 +/- 2.82 mmHg), hydrops affected 18.7% of patients. CONCLUSIONS: The following factors are of bad prognosis in fetal stage of Ebstein anomaly: cardiothoracic index > 0.55, relative foramen ovale-atrial septal <0.3, the obstruction to the outflow tract, a degree of valve displacement > 2.5, absence of reverse flow in the duct arteriosus, ratio right ventricle-left ventricle > 2. The Ebstein anomaly diagnosed in utero has a perinatal mortality of 87.5%.

The Effect of Third Dose of Pfizer/BioNTech and Moderna COVID-19 mRNA Vaccines on IgG Antibody Titers.

With the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, the Centers for Disease Control and Prevention (CDC) authorized the third dose of the Pfizer-BioNTech (BNT162b2) vaccine with the rationale for prolonged elevation of anti-SARS-CoV-2 antibody titers and protection against the SARS-CoV-2 virus. To better understand how administration of the third dose of the Pfizer/BioNTech coronavirus disease 2019 (COVID-19) vaccine affects the incidence and severity of SARS-CoV-2 infections, we administered the third dose of the Pfizer-BioNTech (BNT162b2) to 189 participants. Blood samples were collected from participants during each of their scheduled visits (baseline, week two, week 12, and week 24) and tested for semi-quantitative anti-SARS-CoV-2 immunoglobulin G (IgG) titers. Our results showed that administration of the third dose of the Pfizer-BioNTech (BNT162b2) vaccine elicited elevated anti-SARS-CoV-2 IgG antibodies for the 24-week duration of the study. IgG antibody titers were greatest in week two, and progressively decreased by week 12 and week 24, with statistically significant differences between the IgG antibody titers for each collection date.

Case Report: Cedecea lapagei Infection: Report of a Case in Peru and Review of the Literature.

Cedecea lapagei is a gram-negative, non-encapsulated, facultative anaerobic bacterium that has been reported in only a few cases with varying clinical presentations, drug susceptibility, and treatment since its first isolation in 1981. This study aimed to describe a case report of C. lapagei in Peru and systematically review the documented case reports of individuals infected with C. lapagei. A 59-year-old man who had become bedridden with Parkinson's disease and had epilepsy presented with a 1-week history of fever and sore throat and was admitted. Physical examination revealed an obtundation state and abolished vesicular murmur in the right hemithorax. During hospitalization, the patient was diagnosed with various infections, including tuberculosis, for which he received broad-spectrum antibiotics. In the absence of clinical improvement, a urine culture was performed showing C. lapagei (detected by BD Phoenix M50 system, Vernon Hills, IL). The patient received amoxicillin/clavulanate and was discharged. Case reports of C. lapagei were also searched in five databases on January 28, 2023. Twenty cases of C. lapagei were reported worldwide between 2006 and 2022, 16 of which involved adults. Fever was the most common manifestation (75%), and pneumonia was the primary form of presentation (45%). Moreover, 90% of the patients had at least one comorbidity, and 15% died. Also, most of the isolates were sensitive to ciprofloxacin (81%), meropenem (62%), and amikacin (60%). Overall, C. lapagei should be suspected in compromised hosts, particularly those with pneumonia. Although the bacterium can affect various organs and the antibiotic susceptibility pattern is variable, quinolones, tetracyclines, and carbapenems seem to be the first therapeutic option.

Calibration of piezoelectric positioning actuators using a reference voltage-to-displacement transducer based on quartz tuning forks.

We use a piezoelectric quartz tuning fork to calibrate the displacement of ceramic piezoelectric scanners that are widely employed in scanning probe microscopy. We measure the static piezoelectric response of a quartz tuning fork and find it to be highly linear, nonhysteretic and with negligible creep. These performance characteristics, close to those of an ideal transducer, make quartz transducers superior to ceramic piezoelectric actuators. Furthermore, quartz actuators in the form of a tuning fork have the advantage of yielding static displacements comparable to those of local probe microscope scanners. We use the static displacement of a quartz tuning fork as a reference to calibrate the three axis displacement of a ceramic piezoelectric scanner. Although this calibration technique is a nontraceable method, it can be more versatile than using calibration grids because it enables characterization of the linear and nonlinear response of a piezoelectric scanner in a broad range of displacements, spanning from a fraction of a nanometer to hundreds of nanometers. In addition, the creep and the speed dependent piezoelectric response of ceramic scanners can be studied in detail.

Simple Microcontact Printing Technique to Obtain Cell Patterns by Lithography Using Grayscale, Photopolymer Flexographic Mold, and PDMS.

Microcontact printing using PDMS embossing tools and its variations have aroused the interest of a wide spectrum of research fields, hence the feasibility of defining micro and nanoscale patterns. In this work, we have proposed and demonstrated a novel lithography method based on grayscale patterns printed in a flexographic photopolymer mold and transferred to epoxy resin and a single PDMS stamp to obtain different microprint pattern structures. The geometry of the patterns can be modified by adjusting the layout and grayscale of the stamp patterns. The functionality of this contact printing methodology was validated by generating human induced pluripotent stem cells (hiPSC) patterns. These specific micropatterns can be very useful for achieving complex differentiation in cell lines such as hiPSC. Microfabrication through the new technique provides a promising alternative to conventional lithography for constructing complex aligned surfaces; these structures could be used as components of biological patterns or microfluidic devices.

Influence of binding groups on molecular junction formation.

We study the formation mechanism of molecular junctions using break-junction experiments. We explore the contribution of gold-atom rearrangements in the electrodes by analyzing the junction stretching length, the length of individual plateaus, and the length of the gold one-atom contacts. Comparing the results for alkane dithiols and diamines, we conclude that thiols affect gold electrode dynamics significantly more than amines. This is a vital factor to be considered when comparing different binding groups.

Primovist® (Gadotrexate disodium) magnetic resonance use in benign and malignant kidney diagnosis. / Uso de la resonancia magnetica con Primovist® (Gadotrexate disodio) para diagnostico de lesiones renales benignas y malignas.

OBJECTIVE: To evaluate the quality of the contrast images obtained with a Primovist® (gadoxetate disodium) Magnetic Resonance Image in order to diagnose benign, malignant and malformations in the urinary tract. MATERIAL AND METHODS: A retrospective image and diagnosis review of Primovist® MRI studies performed in liver insufficient patients without apparent renal abnormalities was done, in order to evaluate the urinary tract for irregularities. RESULTS: A total of 117 Primovist® MRI studies performed between july 2014 and November 2018 were reviewed, 5 were excluded because they were incomplete. The average age was 59.6 ± 16.6 years old. The following diagnosis were encountered: 36 simple cysts, 6 perirenal fibrosis after pyelonephritis, 1 renal cancer, 1 renal atrophy, 1 proximal uretheric flexure, 1 bilateral hydronephrosis due to lower urinary obstruction because of benign prostatic hyperplasia and 1 complex cyst. No MRI study was indicated with suspicions of renal abnormalities. Relevant images are included that demonstrate the capability of Primovist® MRI to diagnose renal abnormalities. CONCLUSION: Even though none of the Primovist® MRI studies was done with suspicious of renal abnormalities it was possible to diagnose incidental benign, malignant and malformations of the urinary tract. This study shows how Primovist® MRI can be useful contrast study for urinary tract irregularities.

OBJETIVO: Evaluar la calidad de las imágenes contrastadas del tracto urinario que permitan diagnosticar patologías benignas, malignas y malformaciones con el uso de una resonancia magnética contrastada con Primovist® (gadoxetato disodio). MATERIAL Y METODOS: Se realizó una revisión de las imágenes y diagnósticos del servicio de radiología de manera retrospectiva de pacientes con una resonancia magnética contrastada con Primovist® por padecer insuficiencia hepática sin aparente patología urinaria, con el objeto de buscar diagnósticos incidentales en el tracto urinario superior e inferior. RESULTADOS: Se revisaron durante el periodo de julio del 2014 a noviembre del 2018, 117 estudios, se excluyeron 5 por no contar con el estudio completo para su revaloración. La edad promedio fue de 59,6±16,6 años. Se encontraron 48 anormalidades urinarias sin previa sospecha diagnóstica por lo que fueron considerados como incidentales. A continuación se enumeran los hallazgos renales diagnosticados: 36 quistes simples, 6 cambios perirenales compatibles con secuelas de pielonefritis, 1 cáncer renal, 1 hipotrofia renal, 1 angulación funcional del uréter proximal sin cruce vascular con pelvis extrarenal contralateral, 1 hidronefrosis bilateral secundaria a obstrucción vesical por hiperplasia prostática y 1 quiste complejo. Ningún estudio se indicó por sospecha de anormalidades del tracto urinario. CONCLUSIONES: Aun cuando no era la indicación del estudio de resonancia, fue posible encontrar algunas patologías renales como hallazgos que incluyeron patología benigna, maligna y malformaciones, demostrando que la resonancia magnética con Primovist® se podría realizar como estudio contrastado para patologías renales.

Redefining the Topography of the Tibial Nerve: Updated Treatment Guide for Tibial Nerve Entrapments: An Addendum to Surgical Treatment Protocol for Peripheral Nerve Dysfunction of the Lower Extremity: A Systematic Approach.

Dysfunction of the tibial nerve can progress to painful and potentially disabling conditions. There are multiple sites of entrapment along the course of the tibial nerve. Detailed knowledge of the anatomy and anatomic variations is critical for a surgeon to be able to properly diagnose and treat patients with tibial nerve injuries. Repair of tibial nerve injuries involves a thorough history, physical examination, diagnostic studies, and microsurgical techniques. This article discusses sites of tibial nerve entrapment and use of a surgical algorithm that provides a systematic approach that has been successful within the literature in treating chronic tibial neuritic pain.

Machine Learning Applications and Optimization of Clustering Methods Improve the Selection of Descriptors in Blackberry Germplasm Banks.

Machine learning (ML) and its multiple applications have comparative advantages for improving the interpretation of knowledge on different agricultural processes. However, there are challenges that impede proper usage, as can be seen in phenotypic characterizations of germplasm banks. The objective of this research was to test and optimize different analysis methods based on ML for the prioritization and selection of morphological descriptors of Rubus spp. 55 descriptors were evaluated in 26 genotypes and the weight of each one and its ability to discriminating capacity was determined. ML methods as random forest (RF), support vector machines, in the linear and radial forms, and neural networks were optimized and compared. Subsequently, the results were validated with two discriminating methods and their variants: hierarchical agglomerative clustering and K-means. The results indicated that RF presented the highest accuracy (0.768) of the methods evaluated, selecting 11 descriptors based on the purity (Gini index), importance, number of connected trees, and significance (p value < 0.05). Additionally, K-means method with optimized descriptors based on RF had greater discriminating power on Rubus spp., accessions according to evaluated statistics. This study presents one application of ML for the optimization of specific morphological variables for plant germplasm bank characterization.

Cost-effective fabrication of photopolymer molds with multi-level microstructures for PDMS microfluidic device manufacture.

This paper describes a methodology of photopolymer mold fabrication with multi-level microstructures for polydimethylsiloxane (PDMS) microfluidic device manufacture. Multi-level microstructures can be performed by varying UVA exposure time and channel width. Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and profilometry techniques have been employed to characterize the molds. Multiple molds with multi-level microstructures can be formed in a unique piece. Overall height/depth of the structures reaches up to 677 µm and a minimum of 21 µm. The method provides several advantages such as reduction of fabrication time, multiple structures with diverse topologies, a great variety of depth and height in a single mold and low cost of fabrication. The effectiveness of multi-level microstructure fabrication was evaluated by constructing PDMS microfluidic devices for cell culture and proliferation.

Anatomical, surgical and technical factors influencing continence after radical prostatectomy.

Radical prostatectomy (RP) is the most frequent treatment with curative intent performed for prostate cancer to date. Different surgical approaches (perineal, transperitoneal, and extraperitoneal) and techniques (laparoscopic and robot assisted) have been described to increase the efficiency and potentially diminish the postoperative complications of this procedure. The aim of this narrative review is to investigate and define the factors that influence postprostatectomy urinary continence. We highlighted the anatomical landmarks and the modifications of surgical techniques aimed at improving the continence rates and thus, patient quality of life. After RP, the long-term continence rates range from 84% to 97%. In order to achieve good continence rates, a careful dissection along with meticulous anatomical reconstruction is required. To this end, a detailed knowledge of the periprostatic anatomy is mandatory.

An Archaeometric Characterization of Ecuadorian Pottery.

Ecuadorian pottery is renowned for its beauty and the particularly rich colour of its pigments. However, a major challenge for art historians is the proper assessment of the provenance of individual pieces due to their lack of archaeological context. Of particular interest is the Jama-Coaque culture, which produced fascinating anthropomorphic and zoomorphic pottery from ca. 240 B.C. until the Spanish Conquest of 1532 A.D. in the coastal region of Ecuador. Using a combination of microscopic and spectroscopic techniques, i.e., transmission electron microscopy (TEM), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), energy-dispersive x-ray spectroscopy (EDX), and scanning electron microscopy (SEM); we are able to characterize these pieces. We have found several kinds of iron-oxide based nanostructures in all the colour pigments we investigated for the Jama-Coaque culture, suggesting the same unique volcanic source material was used for their clay. Such nanostructures were absent from the pigment samples studied from other contemporary coastal-Ecuadorian cultures, i.e., the Tumaco-La Tolita and Bahía cultures. In the yellow pigments of goethite we find carbon nanofibres, indicating these pigments were subjected to a thermal treatment. Finally, in the blue, green, and black pigments we detect modern pigments (phthalocyanine blue, lithopone, and titanium white), suggesting modern restoration. Our results demonstrate the power of TEM, Raman, FTIR, EDX, and SEM archaeometric techniques for characterizing pieces without a clear archaeological context. Furthermore, the characterization of nanostructures present in such pieces could be used as a possible fingerprint for a provenance study.

Tetrathiafulvalene-based molecular nanowires.

A new molecular wire suitably functionalized with sulfur atoms at terminal positions and endowed with a central redox active TTF unit has been synthesized and inserted within two atomic-sized Au electrodes; electrical transport measurements have been performed in STM and MCBJ set-ups in a liquid environment and reveal conductance values around 10(-2) G0 for a single molecule.

Association between polymorphisms of the androgen and vitamin D receptor genes with prostate cancer risk in a Mexican population.

INTRODUCTION: Prostate cancer (PCa) is a worldwide health issue, because of its high incidence and mortality. Its etiology is complex and includes certain risk factors such as age, hormonal status, ethnic origin and family history of PCa. Genetic predisposition is proposed as a major risk factor and there are several controversial reports on the association of PCa and gene polymorphism such as the receptors of the androgen receptor (AR) and the vitamin D (VDR). Objective. To evaluate the CAG triplet repeats in the first exon of the AR and polymorphisms in the restriction site Taql in the VDR in Mexicans with PCa. MATERIAL AND METHODS: A total of 68 Mexicans with histopathological diagnosis of PCa and 48 healthy Mexican with normal prostate-specific antigen and rectal exam where included. 10ml of peripheral blood were extracted to isolate DNA and the polymorphisms were evaluated with specific primers for the AR and VDR. RESULTS: The allelic and genetic distributions of the AR and VDR polymorphisms were consistent with the Hardy-Weinberg equilibrium, and there were no statistical differences between the PCa patients and controls (p > 0.05). However, there was a statistical difference between the number of CAG repeats in younger patients with PCa compared to controls (p = 0.045) but when the young patient group was compared versus the elder group there was not stadistically difference (p = 0.085), but the results showed a tendency towards less repetitions of CAG in elder patients. Concerning the VDR, when we analyzed the patients with PCa and a bad pathological prognosis they had a less frequent genotype of TT (p = 0.03). CONCLUSIONS: Our results suggest an association between the VDR and AR gene polymorphisms, and the histopathological score and age at diagnosis in Mexican patients with PCa, respectively. However, it is important to confirm these results in a larger scale study.

Laparoscopic prostate-sparing radical cystectomy: the Montsouris technique and preliminary results.

BACKGROUND AND PURPOSE: Prostate-sparing radical cystectomy has been described in the literature and has proven to be a promising procedure because of the continence and erectile function results which does not necessarily compromise the oncologic outcome in properly selected patients. We report our preliminary results with this technique performed laparoscopically. PATIENTS AND METHODS: A total of 25 patients with an average age of 60 years have undergone this procedure. Through a transperitoneal approach, lymph-node dissection is done with frozen-section examination, and the ureters are ligated and biopsied. The seminal vesicles are dissected, followed by complete mobilization of the bladder. Next the bladder neck is incised followed by the bladder-pedicle dissection. A simple prostatectomy can be performed if required. Finally, the neobladder is reconstructed via a small infraumbilical incision that also permits extraction of the surgical specimen. The neobladder is anastomosed to the prostate capsule. RESULTS: The average surgical time was 285 minutes and the mean blood loss 640 mL. The complications encountered (4) were: one case each of bowel incarceration, urinary leak, lymphocele, and port-site hernia. All but one of the patients are alive at 9-month follow-up, with the one patient dying of cancer progression. No patient presented with daytime incontinence, although seven reported nocturia. There were 20 patients who maintained their preoperative sexual potency, and four described a decrease in erectile function postoperatively. CONCLUSIONS: We have been performing laparoscopic prostate-sparing radical cystectomy for more than 2 years and have found it oncologically safe and reproducible with promising functional benefits. It presents a good option for properly selected patients.