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1.
Materials (Basel) ; 17(13)2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38998438

RESUMEN

The validation of a feasible application for the production of sustainable bricks with local materials in humid and hot climates, which would allow the current housing needs of a constantly growing population with scarce economic resources to be met while also reducing energy inputs for climate control, is a current challenge without a definitive solution. Therefore, this research studied the incorporation of local aggregates and two second-generation materials to produce lime-stabilized Compressed Earth Blocks (CSEBs) using a semi-automatic machine for their manufacture. An initial matrix was designed as a baseline, and three more were developed with variations to incorporate second-generation materials individually and as mixtures. The stabilizer was added in concentrations of 5, 10, and 15%, resulting in a total of 12 batches of CSEBs. Eleven of the studied batches exceed the normative limits for simple compressive strength and initial water absorption coefficient. The best result of simple compressive strength was obtained in two batches of the same matrix that used construction demolition waste (CDW), reaching 4.3 MPa (43% above the minimum limit established by the most restrictive regulations and 115% above the least restrictive). It was possible to produce sustainable bricks in situ with average ambient temperatures of 32 °C and relative humidity of 91%.

2.
JSES Int ; 8(4): 866-872, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39035640

RESUMEN

Background: Biomechanical research demonstrates increased subscapularis abduction range of motion (ROM) when the tendon's upper two-thirds is repaired over-the-top of the center of rotation during reverse shoulder arthroplasty (RSA). This study compares the clinical outcomes of patients undergoing RSA with over-the-top subscapularis repair (OTTR) to patients without repair. Methods: We retrospectively reviewed 97 consecutive RSAs with either OTTR of the subscapularis (N = 75) or no repair (N = 22). Repair was attempted in all patients but not performed if the subscapularis could not be brought to the over-the-top position in 20° of external rotation (ER) and 30° of abduction. Improvements in ROM were compared to the minimal clinically important difference for RSA. Results: The mean follow-up was 3.8 ± 1.6 years. Demographics were similar between groups. Preoperatively, patients undergoing repair had greater ER when compared to those without repair (15 ± 16° vs. 5 ± 12°, P = .003). Postoperatively, patients undergoing repair had greater forward elevation (132 ± 21° vs. 126 ± 22°, P = .268) and abduction (114 ± 26° vs. 106 ± 23°, P = .193) with both exceeding the minimal clinically important difference (-2.9° and -1.9°, respectively); however, not statistically significant. Patients with repair were more frequently able to reach the small of their back postoperatively (65% vs. 21%, P = .006) but had less improvement in ER (13 ± 20° vs. 24 ± 20°, P = .028). Postoperative outcome scores, complications, and reoperations were similar between groups. Discussion: OTTR of the subscapularis in RSA had similar ROM and outcome scores compared to no repair, but a significantly larger proportion of patients with repair achieved functional internal rotation to the small of the back. ER limitations seen after conventional repair may also apply to this novel technique, but without a corresponding detrimental effect on forward elevation or abduction.

3.
Bol. latinoam. Caribe plantas med. aromát ; 22(1): 115-129, ene. 2023. tab, graf, ilus
Artículo en Inglés | LILACS | ID: biblio-1555348

RESUMEN

The stem bark of Geoffroea decorticans (Gill.ex Hook. etArn.) Burk. was used medicinally to cure several skin affections; however, phytochemical and biological antecedents were not found. Analyses of purified methanolic extract from G. decorticans bark (PFGB), realized by silylation derivatization for GC/MS, C18-CC and HPLC followed by two-dimensional TLC and UV-Vis spectroscopy, allowed to characterize nine phenolic compounds, among these, two methoxy flavonoids. Antibacterial assays of PFGB showed the highest activity (MICs = 125 µg/mL) against Staphylococcus aureus (25923) and Enterococcus faecalis (29212) ATCC strains. Moreover, PFGB showed the highest intracellular antioxidant activity at low concentration (5 µg/mL), evaluated by using the fluorescent DA-H2DCF probe on lymphocyte culture; cytotoxic effects on lymphocytes activated or not by LPS were not observed, through Trypan Blue Exclusion and MTT colorimetric assays. The results obtained from the ethnomedicinal approach of this work contribute to the scientific validation of the vulnerary medicinal use of G. decorticans.


La corteza de Geoffroea decorticans (Gill.ex Hook. EtArn.) Burk. se utiliza con fines medicinales para curar diferentes afecciones de la piel; sin embargo, no encontramos antecedentes fitoquímicos y biológicos que validen las propiedades medicinales atribuidas. Analizamos el extracto metanólico purificado de corteza de G. decorticans (PFGB), por CG-EM de la muestra derivatizada por sililación, C18-CC y HPLC seguido de CCF bidimensional, y espectroscopia UV-Vis; estos métodos nos permitieron caracterizar nueve compuestos fenólicos, entre estos, dos metoxi-flavonoides. Los ensayos antibacterianos de PFGB mostraron mayor actividad (CIMs = 125 µg/mL) contra las cepas ATCC de Staphylococcus aureus (25923) y Enterococcus faecalis (29212). Además, PFGB evidenció la mayor actividad antioxidante intracelular a baja concentración(5 µg/mL), evaluada en cultivo de linfocitos, mediante el uso de sonda fluorescente DA-H2DCF; no se observaron efectos citotóxicos sobre linfocitos activados o no por LPS, a través de ensayos colorimétricos con MTT y test de exclusión con azul Tripán. Los resultados obtenidos del abordaje etnomedicinal de este trabajo, contribuyen con la validación científica del uso medicinal vulnerario de G. decorticans.


Asunto(s)
Árboles/química , Extractos Vegetales/farmacología , Compuestos Fenólicos , Fitoquímicos/farmacología , Plantas Medicinales/química , Extractos Vegetales/aislamiento & purificación , Medicina Tradicional , Antibacterianos/química
4.
Nat Prod Res ; 37(15): 2596-2601, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35297708

RESUMEN

A fraction enriched in triterpenoid saponins (F4) from Anagallis arvensis L. was chemically characterized by UHPLC-ESI-QTOF-MS/MS and NMR analyses. The results proposed the presence of nine monodesmosidic saponins derived from oleanolic acid, including two reported for the first time for this species, 3: 3-O-{ß-D-glucopyranosyl (1→4)-[ß-D-xylopyranosyl (1→2)]-ß-D-glucopyranosyl (1→4)-[ß-D-glucopyranosyl (1→2)]-α-L-arabinopyranosyl}-13ß, 28-epoxy- 22 acetyl- 28 methoxy-16α, 24-oleananediol and 4: 3-O-{ß-D-glucopyranosyl (1→4)-ß-D-glucopyranosyl (1→4)-[ß-D-xylopyranosyl (1→2)]-ß-D-glucopyranosyl (1→4)-[ß-D-glucopyranosyl (1→2)]-α-L-arabinopyranosyl}-13ß, 28-epoxy- 16α, 30-oleananediol. Furthermore, haemolytic activity was determined by dot-blot autography, and cytotoxicity on human lymphocyte cultures was analysed according to metabolic activity (MTT assay) and membrane integrity (Trypan blue exclusion test). F4 showed mild cytotoxicity (%V > 50% at 100 µg/mL) on human lymphocytes under conditions of activation or not by LPS; moreover, showed haemolytic activity between 50 and 500 µg. This work contributed to phytochemical knowledge of the triterpenoid saponins from A. arvensis, and its cytotoxic effects on normal human cells.


Asunto(s)
Saponinas , Triterpenos , Humanos , Cromatografía Líquida de Alta Presión , Espectrometría de Masas en Tándem , Saponinas/farmacología , Saponinas/química , Triterpenos/farmacología , Triterpenos/química , Estructura Molecular
5.
Braz. J. Anesth. (Impr.) ; 73(5): 676-679, 2023. graf
Artículo en Inglés | LILACS | ID: biblio-1520351

RESUMEN

Abstract Patients with burns to the head and neck maybe difficult to intubate or ventilate via facemask. Furthermore, post-burn scarring and microstomia may reduce the success of rescue supraglottic airway placement. While awake tracheal intubation using a flexible intubation scope is considered the optimal technique for these patients, it may not always be feasible in the pediatric population. We report a case of successful management of a difficult airway in a child with extensive post-burn head and neck deformity using a noninvasive positive pressure system to aid with inhalational induction and deep sedation during intubation using a flexible scope.


Asunto(s)
Humanos , Preescolar , Niño , Ventilación no Invasiva , Intubación Intratraqueal , Pediatría , Quemaduras
6.
Materials (Basel) ; 15(19)2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36234178

RESUMEN

The building industry generates millions of tons of construction and demolition waste annually (12 million tons/year are generated in Mexico, of which only 4% is reused or recycled). Concomitantly, the demand for goods and services by the building industry causes significant environmental impacts. On the other hand, plastic waste is also difficult to assimilate into the environment in the short term, and its recovery is of special interest. Therefore, this research focuses on the feasibility of the manufacture of Partition Blocks (essential building element) through the combination of construction and demolition waste (CDW), polyethylene terephthalate (PET) plastic flakes, dust from tire shredding, and residue from the sugar industry (bagasse). The results of this study show that the Partition Blocks made with CDW and PET reach an average compressive strength of 115.003 kgf/cm2 (11.278 MPa) (suitable for structural use according to Mexican regulations); the use of lime enhances the consistency of the mixture of CDW and PET (increases its cohesion and homogeneity); and finally, these Partition Blocks have a cost comparable to the current conventional Partition Blocks made with virgin material, thus, conferring them validity as a feasible recycling option for these residues.

7.
Cureus ; 14(1): e21424, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35198329

RESUMEN

Obstructive sleep apnea is a serious health issue affecting more than one billion people worldwide. Although continuous positive airway pressure is the mainstay for the treatment of obstructive sleep apnea, hypoglossal nerve stimulation is a surgical option for patients who are unable to tolerate or adhere to this therapy. As more hypoglossal nerve stimulators are implanted, these patients will present with increasing frequency for medical procedures requiring general anesthesia or deep sedation. We describe our experience with one such patient and hope this information can be used to develop future guidelines to aid in the anesthetic management of these patients.

8.
Materials (Basel) ; 14(6)2021 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-33801138

RESUMEN

The porosity of mortars with recycled ceramic aggregates (10, 20, 30, 50, and 100% as a replacement of natural aggregate) was evaluated and analyzed using three different techniques. The results of gas adsorption (N2), Scanning Electron Microscopy (SEM) image analysis and open porosity allowed establishing the relationship between the recycled aggregate content and the porosity of these mortars, as well as the relationship between porosity and the physical and mechanical properties of the mortars: absorption, density, compressive strength, modulus of elasticity, and drying shrinkage. Using the R2 coefficient and the equation typology as criteria, additional data such as Brunauer, Emmett, and Teller (BET) surface area (N2 adsorption) established significant correlations with the mentioned properties; with SEM image analysis, no explanatory relationships could be established; and with open porosity, revealing relationships were established (R2 > 0.9). With the three techniques, it was confirmed that the increase in porosity is related to the increase in the amount of ceramic aggregate; in particular with gas adsorption (N2) and open porosity. It was concluded that the open porosity technique can explain the behavior of these recycled mortars with more reliable data, in a simple and direct way, linked to its establishment with a more representative sample of the mortar matrix.

10.
Pain Med ; 22(6): 1253-1260, 2021 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-33537703

RESUMEN

BACKGROUND: The obturator nerve runs along the posterolateral walls of the bladder and electrosurgical stimulation in this region can result in adductor spasm which can occur suddenly and unexpectedly with potentially catastrophic results. METHODS: Sixty patients were prospectively randomized to receive either a single-injection ultrasound-guided obturator nerve block (ONB) or intravenous rocuronium after induction of general anesthesia (i.e., neuromuscular block [NMB]). The primary objective was to compare the incidence of adductor spasm during posterolateral bladder tumor resection when ONB or NMB was used. Secondary objectives included assessment of fall risk and incidence of adverse events. RESULTS: Five patients in the ONB group and six in the NMB group had nonlateral wall lesions. One patient in the ONB group suffered a cardiac arrest after induction of general anesthesia. Of the remaining 48 patients, six (10.2%) experienced adductor spasm. Most of these patients were in the NMB group (5/24, 20.8%), with only one patient (1/24, 4.2%) experiencing obturator reflex in the ONB group; this difference was not statistically significant (P=0.19). Patients in the ONB group had a greater decrease in mean hip adductor strength. Our study population was found to be at high risk of falls before surgery. There were no statistically significant group differences in the Timed Up and Go test, with time to perform the test increasing in both groups. CONCLUSIONS: Both techniques are safe and efficacious for preventing adductor spasm. Our data and experience suggest that the ONB is relatively easy to perform and should be considered in patients with posterolateral bladder tumors.


Asunto(s)
Bloqueo Nervioso , Bloqueo Neuromuscular , Neoplasias de la Vejiga Urinaria , Humanos , Bloqueo Nervioso/efectos adversos , Bloqueo Neuromuscular/efectos adversos , Equilibrio Postural , Espasmo , Estudios de Tiempo y Movimiento , Neoplasias de la Vejiga Urinaria/cirugía
11.
Heliyon ; 6(10): e05174, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33083621

RESUMEN

Tessaria dodoneifolia [Asteraceae] is traditionally employed in Northwestern Argentina for fungal infections treatment. We report the antifungal activity guided isolation and identification of substances from aerial parts of this species, both individually and in combination with fluconazole (FLU), against Candida albicans strains. Two antifungal flavanones were identified as naringenin (NAR) and pinocembrin (PIN). These compounds could individually inhibit the growth of C. albicans strains. Combinations of NAR and PIN with FLU were synergistic against the FLU resistant and sensitive C. albicans strains. Genotoxic and cytotoxic evaluations were also performed. NAR, PIN and their combinations with FLU did not have a genotoxic effect on Bacillus subtilis rec strains. Finally, these compounds did not show cytotoxicity at concentrations below 80 µg/mL.

12.
Materials (Basel) ; 13(16)2020 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-32824406

RESUMEN

The construction sector generates 14,000 t/d of construction waste in Mexico City, these materials do not have real applications and end up accumulating in landfills. This work, the objective of which was to analyze the physicochemical and mineralogical properties of soil and construction waste used in the manufacture of Recoblocks, is divided in five stages. First, the excavation material was submitted to field tests. Physical and chemical tests were then carried out on construction waste. Subsequently, the optimal mixture for making Recoblocks was determined. Next, Recoblocks were evaluated and compared with blocks made with water only, without mucilage of Opuntia ficus, and finally a feasibility study was performed. The X-ray diffraction study showed the presence of plagioclase, minerals that improve bending resistance, hardness, durability, as well as resistance to stress in a material. Compared to blocks manufactured without mucilage, the use of Opuntia ficus mucilage increased the compressive strength of the material by 59%, as well as the erodibility. Recoblocks are an environmentally friendly option because they are based on recycled materials, dried under the sun, which eliminates the use of brick oven. The production cost per unit is just USD 0.19, so it is a viable option as a building material.

15.
Materials (Basel) ; 12(13)2019 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-31288494

RESUMEN

Recycled aggregates (RA) from construction and demolition can be used in permeable concretes (PC), improving the environment. PCs have a significant porous network, their cement paste and the interaction between the paste and the RA establishing their strength. Therefore, it is important to evaluate the porosity in the interfacial transition zones. The porosity of the cement paste, the aggregate and the interfacial transitional zones (ITZ) of a PC with recycled coarse aggregates (RCA) and silica fume (SF) is measured by means of image analysis-scanning electron microscope (IA)-(SEM) and by mapping the chemical elements with an SEM-EDS (energy dispersive spectrometer) detector microanalysis linked to the SEM and, as a contrast, the mercury intrusion porosimetry technique (MIP). In the IA process, a "mask" was created for the aggregate and another for the paste, which determined the porosity percentage (for the anhydrous material and the products of hydration). The results showed that using SF caused a reduction (32%) in the cement paste porosity in comparison with the PC with RA. The use of RA in the PC led to a significant increase (190%) in the porosity at different thicknesses of ITZ compared with the reference PC. Finally, the MIP study shows that the use of SF caused a decrease in the micropores, mesopores and macropores.

16.
A A Pract ; 13(4): 145-147, 2019 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-30985315

RESUMEN

Patients presenting for major vascular surgery are often elderly, medically complex, and at increased risk for general anesthesia-related complications. A search of the published literature produced no citation regarding PECS II block in the setting of extra-anatomic bypass procedures. We present a case report describing the use of the deep injection of the PECS II block in this context. Although further investigation is needed to determine the role of truncal blocks in major vascular surgery, our case illustrates that peripheral nerve blocks, combined with continuous spinal anesthesia, may be used as an alternative to general anesthesia for axillofemoral-femoral bypass.


Asunto(s)
Derivación Axilofemoral con Injerto/métodos , Bloqueo Nervioso/métodos , Anciano , Enfermedad de la Arteria Coronaria/complicaciones , Insuficiencia Cardíaca/complicaciones , Humanos , Masculino , Manejo del Dolor , Enfermedad Pulmonar Obstructiva Crónica/complicaciones
17.
Materials (Basel) ; 12(4)2019 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-30791583

RESUMEN

This study analyzes the effect of using waste by-products generated in the process of granite cutting as part of the granular structure of Ultra High Performance Concrete (UHPC). The manufactured concrete has a compressive strength greater than 115 MPa. This study substitutes 35%, 70% and 100% of the volume of micronized quartz powder (<40 µm) with granite cutting waste. This is an innovative study where the feasibility of using waste from granite quarries as a replacement for micronized quartz in UHPC has been analyzed. The results show an improvement in the workability and compressive strength of UHPC, for all substitution ratios. The flexural strength and tensile strength increase when the substitution ratio is 35%, and even the values obtained for 100% substitution are acceptable. In view of the results obtained in this study, granite cutting waste, instead of the micronized quartz powder usually used, is a viable alternative for the manufacture of expectedly more sustainable UHPC.

18.
A A Pract ; 12(1): 5-8, 2019 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-29994871

RESUMEN

Autosomal dominant or benign osteopetrosis is a rare genetic disorder of osteoclasts that results in dense but brittle bone structures. Patients with osteopetrosis may be scheduled for total knee arthroplasty to treat painful and functionally limiting osteoarthrosis. A search of the published literature produced no citation concerning anesthesia for patients with autosomal dominant osteopetrosis undergoing total knee arthroplasty. We present a case report detailing our experience and discuss considerations for the care of future patients with autosomal dominant osteopetrosis.


Asunto(s)
Anestésicos/administración & dosificación , Artroplastia de Reemplazo de Rodilla/métodos , Osteopetrosis/cirugía , Administración Intravenosa , Dexametasona/administración & dosificación , Humanos , Ketamina/administración & dosificación , Masculino , Persona de Mediana Edad , Osteopetrosis/complicaciones , Manejo del Dolor/métodos , Ropivacaína/administración & dosificación , Resultado del Tratamiento
20.
Materials (Basel) ; 10(2)2017 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-28772540

RESUMEN

In the field of construction, sustainable building materials are currently undergoing a process of technological development. This study aims to contribute to understanding the behavior of the fundamental properties of concretes prepared with recycled coarse aggregates that incorporate a polyethylene terephthalate (PET)-based additive in their matrix (produced by synthesis and glycolysis of recycled PET bottles) in an attempt to reduce their high porosity. Techniques to measure the gas adsorption, water porosity, Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) were used to evaluate the effect of the additive on the physical, mechanical and microstructural properties of these concretes. Porosity reductions of up to 30.60% are achieved with the addition of 1%, 3%, 4%, 5%, 7% and 9% of the additive, defining a new state in the behavioral model of the additive (the overdosage point) in the concrete matrix; in addition, the porous network of these concretes and their correlation with other physical and mechanical properties are also explained.

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