Distinct nitrogen isotopic compositions of healthy and cancerous tissue in mice brain and head&neck micro-biopsies.

BACKGROUND: Cancerous cells can recycle metabolic ammonium for their growth. As this ammonium has a low nitrogen isotope ratio (15N/14N), its recycling may cause cancer tissue to have lower 15N/14N than surrounding healthy tissue. We investigated whether, within a given tissue type in individual mice, tumoral and healthy tissues could be distinguished based on their 15N/14N. METHODS: Micro-biopsies of murine tumors and adjacent tissues were analyzed for 15N/14N using novel high-sensitivity methods. Isotopic analysis was pursued in Nude and C57BL/6 mice models with mature orthotopic brain and head&neck tumors generated by implantation of H454 and MEERL95 murine cells, respectively. RESULTS: In the 7 mice analyzed, the brain tumors had distinctly lower 15N/14N than healthy neural tissue. In the 5 mice with head&neck tumors, the difference was smaller and more variable. This was at least partly due to infiltration of healthy head&neck tissue by tumor cells. However, it may also indicate that the 15N/14N difference between tumoral and healthy tissue depends on the nitrogen metabolism of the healthy organ in question. CONCLUSIONS: The findings, coupled with the high sensitivity of the 15N/14N measurement method used here, suggest a new approach for micro-biopsy-based diagnosis of malignancy as well as an avenue for investigation of cancer metabolism.

Testosterone use in postmenopausal women.

The physiological, clinical and therapeutic aspects of testosterone in women's health are still a matter of controversy and debate. Quality evidence data of clinical trials favors the use of transdermal testosterone in postmenopausal women with female sexual dysfunction causing distress. Doses of testosterone should approximate physiological testosterone levels found in premenopausal women, avoiding supraphysiological concentrations that expose women to adverse events. Short-term treatment periods have been shown to be effective and safe in postmenopausal women with hypoactive sexual desire disorder/dysfunction. However, long-term safety of testosterone use must be determined.

Facilitating the design of HL7 domain models through a model-driven solution.

BACKGROUND AND GOAL: Health information systems are increasingly sophisticated and developing them is a challenge for software developers. Software engineers usually make use of UML as a standard model language that allows defining health information system entities and their relations. However, working with health system requires learning HL7 standards, that defines and manages standards related to health information systems. HL7 standards are varied, however this work focusses on v2 and v3 since these are the most used one on the area that this work is being conducted. This works aims to allow modeling HL7 standard by using UML. METHODS: Several techniques based on the MDE (Model-Driven Engineering) paradigm have been used to cope with it. RESULTS: A useful reference framework, reducing final users learning curve and allowing modeling maintainable and easy-going health information systems. CONCLUSIONS: By using this approach, a software engineer without any previous knowledge about HL7 would be able to solve the problem of modeling HL7-based health information systems. Reducing the learning curve when working in projects that need HL7 standards.

Deglacial pulses of deep-ocean silicate into the subtropical North Atlantic Ocean.

Growing evidence suggests that the low atmospheric CO2 concentration of the ice ages resulted from enhanced storage of CO2 in the ocean interior, largely as a result of changes in the Southern Ocean. Early in the most recent deglaciation, a reduction in North Atlantic overturning circulation seems to have driven CO2 release from the Southern Ocean, but the mechanism connecting the North Atlantic and the Southern Ocean remains unclear. Biogenic opal export in the low-latitude ocean relies on silicate from the underlying thermocline, the concentration of which is affected by the circulation of the ocean interior. Here we report a record of biogenic opal export from a coastal upwelling system off the coast of northwest Africa that shows pronounced opal maxima during each glacial termination over the past 550,000 years. These opal peaks are consistent with a strong deglacial reduction in the formation of silicate-poor glacial North Atlantic intermediate water (GNAIW). The loss of GNAIW allowed mixing with underlying silicate-rich deep water to increase the silicate supply to the surface ocean. An increase in westerly-wind-driven upwelling in the Southern Ocean in response to the North Atlantic change has been proposed to drive the deglacial rise in atmospheric CO2 (refs 3, 4). However, such a circulation change would have accelerated the formation of Antarctic intermediate water and sub-Antarctic mode water, which today have as little silicate as North Atlantic Deep Water and would have thus maintained low silicate concentrations in the Atlantic thermocline. The deglacial opal maxima reported here suggest an alternative mechanism for the deglacial CO2 release. Just as the reduction in GNAIW led to upward silicate transport, it should also have allowed the downward mixing of warm, low-density surface water to reach into the deep ocean. The resulting decrease in the density of the deep Atlantic relative to the Southern Ocean surface promoted Antarctic overturning, which released CO2 to the atmosphere.

Management of pediatric tibial tubercle fractures: Is surgical treatment really necessary?

Fractures of the anterior tibial tubercle are infrequent lesions. They often occur in male adolescent athletes, usually in relation with sports involving powerful jumps. We present a retrospective study of 10 patients, with an average age of 15.1 years, all of them males, and a total of 11 acute avulsions of the anterior tibial tubercle. We analyzed the etiology of the lesion, the type of treatment used as well as non-weight bearing period, protected immobilization period, and time until sports reincorporation. We obtained 11 acute avulsions: one case of type I; three cases of type II; four cases of type III; and three cases of type IV. Five cases were treated conservatively, including the three cases of type IV, and surgery was only performed in six cases since an anatomical reduction was not obtained with closed reduction. The results were satisfactory in all cases, with 100% percentage of sport reincorporation in less de 25 weeks. We registered only one complication, intolerance of material, which did not require additional surgeries. These fractures, although rare, have an excellent prognosis. Even if they are often treated surgically, we have obtained good results with the conservative treatment in patterns previously reported as surgical.

Measurement of mean thickness of transparent samples using simultaneous phase shifting interferometry with four interferograms.

In this research a novel interferometric system is reported, which allows the generation of four simultaneous interferograms with phase shifts of π/2. The system consists of three coupled interferometers: a rectangular Sagnac interferometer which generates a primary pattern with crossed circular polarizations, coupled to two Michelson interferometers which operate as a multiplexing system, and generating replicas of the primary pattern. The two coupled Michelson interferometers generate four patterns retaining their polarization properties, which allow independent phase shifts by placing a linear polarizer over each pattern, thereby, four interferograms with relative phase shifts of π/2 are obtained. The optical phase is calculated using the well-known four-step algorithm. With knowledge of the optical phase, different properties of the samples can be calculated or analyzed; in this case, by knowing the mean refractive index, we can calculate the mean thickness of test objects. The results obtained for static transparent samples are presented. The capability of the system to analyze dynamic events is shown when results for the calculation of a temperature field of a heat flow are presented.

Working with the HL7 metamodel in a Model Driven Engineering context.

HL7 (Health Level 7) International is an organization that defines health information standards. Most HL7 domain information models have been designed according to a proprietary graphic language whose domain models are based on the HL7 metamodel. Many researchers have considered using HL7 in the MDE (Model-Driven Engineering) context. A limitation has been identified: all MDE tools support UML (Unified Modeling Language), which is a standard model language, but most do not support the HL7 proprietary model language. We want to support software engineers without HL7 experience, thus real-world problems would be modeled by them by defining system requirements in UML that are compliant with HL7 domain models transparently. The objective of the present research is to connect HL7 with software analysis using a generic model-based approach. This paper introduces a first approach to an HL7 MDE solution that considers the MIF (Model Interchange Format) metamodel proposed by HL7 by making use of a plug-in developed in the EA (Enterprise Architect) tool.

Structural analysis of potato starch transformation during high-energy ball-milling: Oxygen and humidity content effects.

High Energy Ball-Milling (HEBM) modifies starchs' granule morphology, physicochemical properties, and chemical structure. However, understanding how the HEBM changes the starch chemical structure is necessary to control these modifications. Therefore, this study aimed to investigate the changes in potato starch's long- and short-range molecular order during HEBM at different environmental conditions such as oxygen (Air) and humidity content. Due to the correlation between the starch modification and the energy supplied (Esupp) by the HEBM, Burgio's equation was used to calculate this energy. The starch transformation was followed by X-ray diffraction, Fourier Transform-Infrared Spectroscopy, and Raman spectroscopy. A Principal Component Analysis (PCA) was conducted to reduce the HEBM variables. PAC analysis demonstrated that the different oxygen-humidity conditions do not affect the HEBM of potato starch. Based on the starch chemical structure transformation correlated with Esupp during HEBM, four stages were observed: orientation, modification, mechanolysis, and over-destruction. It was identified for the first time that at low milling energy (<1.5 kJ/g, orientation stage), the glycosidic rings change their orientation, and starch-water interaction increases while the starch's organization reduces. Ergo, the potato starch could be more susceptible to chemical modifications during the first two stages.

Concurrent uper limb and hip fracture in the elderly: experience at our centre. / Fracturas concomitantes de miembro superior y cadera en pacientes mayores de 65 años: experiencia en nuestro centro.

INTRODUCTION: The incidence of hip fracture in the elderly is on the rise, occasionally accompanied by concurrent upper limb fractures. Our investigation aims to determine whether these patients experience poorer functional outcomes, prolonged hospitalization, or higher mortality rates when compared to those with isolated hip fracture. MATERIAL AND METHODS: We retrospectively reviewed 1,088 elderly patients admitted to our centre with hip fracture between January 2017 and March 2020. We recorded the presence of concomitant fractures and their treatment. We analyzed the duration of hospital stay, in-hospital mortality and function. RESULTS: We identified 63 patients with concomitant upper limb fracture (5.6%). Among them, 93.7% were women, and the average age was 86.4 years. 80.9% of the upper limb fractures were distal radius or proximal humerus. Patients with concomitant fracture had increased length of stay (mean, 19.6 vs, 12.8, p=0.002), decreased proportion of patients returning to their own home at discharge (23.6% vs, 26.3%, p=0.042) and increased in-hospital mortality rate (9.5% vs, 5.9%, p=0.003). CONCLUSIONS: Patients with concomitant upper limb fracture require a longer length of stay and exhibit an elevated in-hospital mortality rate. Furthermore, this condition is associated with a reduced short-term functional recovery, thereby decreasing the chances of the patient returning home upon hospital discharge.

Evidence of an Off-Resonant Electronic Transport Mechanism in Helicenes.

Helical molecules have been proposed as candidates for producing spin-polarized currents, even at room conditions, due to their chiral asymmetry. However, describing their transport mechanism in single molecular junctions is not straightforward. In this work, we show the synthesis of two novel kinds of dithia[11]helicenes to study their electronic transport in break junctions among a series of three helical molecules: dithia[n]helicenes, with n = 7, 9, and 11 molecular units. Our experimental measurements and clustering-based analysis demonstrate low conductance values that remain similar across different applied voltages and molecules. Additionally, we assess the length dependence of the conductance for each helicene, revealing an exponential decay characteristic of off-resonant transport. This behavior is primarily attributed to the misalignment between the energy levels of the molecule-electrodes system. The length dependence trend described above is supported by ab initio calculations, further confirming an off-resonant transport mechanism.

Biogenic-to-lithogenic handoff of particulate Zn affects the Zn cycle in the Southern Ocean.

Zinc (Zn) is vital to marine organisms. Its active uptake by phytoplankton results in a substantial depletion of dissolved Zn, and Zn bound to particulate organic matter replenishes dissolved Zn in the ocean through remineralization. However, we found that particulate Zn changes from Zn bound to phosphoryls in cells to recalcitrant inorganic pools that include biogenic silica, clays, and iron, manganese, and aluminum oxides in the Southern Ocean water column. The abundances of inorganic pools increase with depth and are the only phases preserved in sediments. Changes in the particulate-Zn speciation influence Zn bioavailability and explain the decoupling of Zn and phosphorus and the correlation of Zn and silicon in the water column. These findings reveal a new dimension to the ocean Zn cycle, implicating an underappreciated role of inorganic Zn particles and their impact on biological productivity.

Unraveling the Interplay between Quantum Transport and Geometrical Conformations in Monocyclic Hydrocarbons' Molecular Junctions.

In the field of molecular electronics, especially in quantum transport experiments, determining the geometrical configurations of a single molecule trapped between two electrodes can be challenging. To address this challenge, we employed a combination of molecular dynamics (MD) simulations and electronic transport calculations based on density functional theory to determine the molecular orientation in our break-junction experiments under ambient conditions. The molecules used in this study are common solvents used in molecular electronics, such as benzene, toluene (aromatic), and cyclohexane (aliphatic). Furthermore, we introduced a novel criterion based on the normal vector of the surface formed by the cavity of these ring-shaped monocyclic hydrocarbon molecules to clearly define the orientation of the molecules with respect to the electrodes. By comparing the results obtained through MD simulations and density functional theory with experimental data, we observed that both are in good agreement. This agreement helps us to uncover the different geometrical configurations that these molecules adopt in break-junction experiments. This approach can significantly improve our understanding of molecular electronics, especially when using more complex cyclic hydrocarbons.