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1.
New Phytol ; 242(6): 2411-2429, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38659154

RESUMEN

Bryophytes, including the lineages of mosses, liverworts, and hornworts, are the second-largest photoautotroph group on Earth. Recent work across terrestrial ecosystems has highlighted how bryophytes retain and control water, fix substantial amounts of carbon (C), and contribute to nitrogen (N) cycles in forests (boreal, temperate, and tropical), tundra, peatlands, grasslands, and deserts. Understanding how changing climate affects bryophyte contributions to global cycles in different ecosystems is of primary importance. However, because of their small physical size, bryophytes have been largely ignored in research on water, C, and N cycles at global scales. Here, we review the literature on how bryophytes influence global biogeochemical cycles, and we highlight that while some aspects of global change represent critical tipping points for survival, bryophytes may also buffer many ecosystems from change due to their capacity for water, C, and N uptake and storage. However, as the thresholds of resistance of bryophytes to temperature and precipitation regime changes are mostly unknown, it is challenging to predict how long this buffering capacity will remain functional. Furthermore, as ecosystems shift their global distribution in response to changing climate, the size of different bryophyte-influenced biomes will change, resulting in shifts in the magnitude of bryophyte impacts on global ecosystem functions.


Asunto(s)
Briófitas , Cambio Climático , Ciclo del Nitrógeno , Agua , Briófitas/fisiología , Agua/metabolismo , Ciclo del Carbono , Carbono/metabolismo , Nitrógeno/metabolismo , Ecosistema
3.
Bol Med Hosp Infant Mex ; 80(Supl 1): 040-046, 2023 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-36917807

RESUMEN

Background: Robinow syndrome is a rare disease with short stature, characteristic phenotypical abnormalities, and intellectual integrity in most cases. Case report: We present the case of a 13-year and one-month-old male who came for medical consultation at 3 years of age due to short stature. Additionally, the patient showed craniofacial dysmorphia, congenital heart disease, and growth hormone deficiency. As per family history, the mother presented the same phenotype. The genetic study identified an unreported variant of the WNT5A gene. Conclusions: The patient initiated growth hormone treatment at a dose of 0.7 U/kg/week at 4 years of age with favorable results, increasing his height from the < 1st percentile to the 44th percentile.

4.
Bol. méd. Hosp. Infant. Méx ; 80(supl.1): 40-46, 2023. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1513764

RESUMEN

Abstract Background: Robinow syndrome is a rare disease with short stature, characteristic phenotypical abnormalities, and intellectual integrity in most cases. Case report: We present the case of a 13-year and one-month-old male who came for medical consultation at 3 years of age due to short stature. Additionally, the patient showed craniofacial dysmorphia, congenital heart disease, and growth hormone deficiency. As per family history, the mother presented the same phenotype. The genetic study identified an unreported variant of the WNT5A gene. Conclusions: The patient initiated growth hormone treatment at a dose of 0.7 U/kg/week at 4 years of age with favorable results, increasing his height from the < 1st percentile to the 44th percentile.


Resumen Introducción: El síndrome de Robinow es una enfermedad rara en la que se presentan estatura baja, anomalías fenotípicas características y, en la mayoría de los casos, integridad intelectual. Caso clínico: Se presenta el caso de un paciente de sexo masculino de 13 años y 1 mes de edad quien acudió a consulta a los 3 años por estatura baja. Adicionalmente, el paciente presentaba dismorfias craneofaciales, cardiopatía congénita y deficiencia de hormona de crecimiento. Como antecedentes familiares, la madre presentó el mismo fenotipo. El estudio genético identificó una variante no reportada del gen WNT5A. Conclusiones: El paciente inició tratamiento con hormona del crecimiento a una dosis de 0.7 U/kg/semana a los 4 años de edad con resultados favorables, aumentando su estatura del percentil < 1 a percentil 44.

5.
Curr Vasc Pharmacol ; 20(6): 527-533, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36043781

RESUMEN

OBJECTIVE: Obesity, a major health issue worldwide, is associated with increased cardiovascular risk, endothelial dysfunction, and arterial stiffness. Tadalafil has been demonstrated to improve vascular parameters. AIM: To evaluate the effect of a single 20 mg dose of tadalafil on flow-mediated dilation and hemodynamic and arterial stiffness markers. METHODS: A randomized, double-blind, placebo-controlled study was conducted on 80 participants (41 assigned to placebo and 39 to tadalafil) with grade 1 obesity, to evaluate the acute effect of a single dose of 20 mg of tadalafil on flow-mediated dilation and hemodynamic and arterial stiffness markers. RESULTS: Tadalafil did not modify flow-mediated dilation. However, it significantly lowered systolic blood pressure (SBP) (130.6±17.1 vs. 125.0±12.7 mmHg, p=0.011), diastolic blood pressure (82.7±18.2 vs. 76.5±11.8 mmHg, p≤0.001), central systolic blood pressure (116.33±19.16 vs. 109.90±15.05 mmHg, p=0.001), the augmentation index (69.1±17.1 vs. 65.7±14.4, p=0.012), and brachial-ankle pulse wave velocity (1229.7±218.4 vs. 1164.0±181.7, p=0.001). CONCLUSION: A single dose of tadalafil did not modify flow-mediated dilation in patients with grade 1 obesity but improved blood pressure and brachial-ankle pulse wave velocity.


Asunto(s)
Rigidez Vascular , Humanos , Análisis de la Onda del Pulso , Tadalafilo/efectos adversos , Índice Tobillo Braquial , Dilatación , Presión Sanguínea , Hemodinámica , Obesidad/diagnóstico , Obesidad/tratamiento farmacológico , Método Doble Ciego
6.
Front Surg ; 9: 747671, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35433812

RESUMEN

Splanchnic vein thrombosis is an unusual manifestation of venous thromboembolism and includes portal vein thrombosis, mesenteric veins thrombosis, splenic vein thrombosis, and the Budd-Chiari syndrome. The most common risk factors include hematologic and autoimmune disorders, hormonal therapy, liver cirrhosis, solid abdominal cancer, recent abdominal surgery, and abdominal infections or inflammatory conditions, such as pancreatitis. Splanchnic vein thrombosis in acute pancreatitis is most commonly associated with the severe form of the disease and pancreatic necrosis. This report describes a case of splanchnic vein thrombosis as a complication of necrotizing acute pancreatitis in a pediatric patient. Splanchnic vein thrombosis was incidentally detected on contrast-enhanced computed tomography to assess the pancreas. There was no evidence of prior risk factors for the thrombotic condition. The patient was treated with anticoagulation and showed complete resolution after recovery from necrotizing acute pancreatitis, at a 16-month follow-up. The complication of necrotizing acute pancreatitis with splanchnic vein thrombosis in pediatric age is a rare presentation.

7.
J Med Food ; 24(12): 1264-1270, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34788550

RESUMEN

One of the proposed mechanisms for the development of diabetic nephropathy (DN) is the increase of end products of advanced glycosylation (AGEs), which bind to its receptor (RAGE), favoring nephron cellular damage. An isoform of this receptor is soluble RAGE (sRAGE), which can antagonize AGE-altered intracellular signaling. It has known that green tea extract (GTE) increases the expression of sRAGE, but it is unknown whether this could improve kidney function. The objective of this study was to evaluate the effect of the administration of GTE on the concentrations of sRAGE, renal function, and metabolic profile in patients with type 2 diabetes mellitus (T2DM) and DN. A randomized, double-blinded, placebo-controlled clinical trial was carried out in 39 patients who received GTE (400 mg every 12 h) or placebo for 3 months. sRAGE levels, renal function, and metabolic parameters were determined before and after the intervention. In the GTE group, there were statistically significant increase on sRAGE (320.55 ± 157.63 pg/mL vs. 357.59 ± 144.99 pg/mL; P = .04) and glomerular filtration rate (GFR; 66.44 ± 15.17 mL/min/1.73 m2 vs. 71.70 ± 19.33 mL/min/1.73 m2; P = .04), and a statistically significant decrease in fasting serum glucose (7.62 ± 3.00 mmol/L vs. 5.86 ± 1.36 mmol/L; P ≤ .01) and triacylglycerols (1.91 ± 0.76 mmol/L vs. 1.58 ± 0.69; P = .02). Administration of GTE increases the serum concentration of sRAGE and the GFR and decreases the concentration of fasting serum glucose and triacylglycerols. The study was registered in ClinicalTrials.gov with the identifier NCT03622762.


Asunto(s)
Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Extractos Vegetales/farmacología , Receptor para Productos Finales de Glicación Avanzada/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Nefropatías Diabéticas/tratamiento farmacológico , Humanos , Riñón/fisiología ,
8.
Invest Clin ; 56(2): 137-54, 2015 Jun.
Artículo en Español | MEDLINE | ID: mdl-26299055

RESUMEN

In recent decades, many compounds with central dopaminergic activity have been designed, synthesized and evaluated pharmacologically. However, it has not been possible to obtain a drug able to improve or cure diseases involving dopaminergic regulation in the central nervous system, such as Parkinson's disease and schizophrenia, among others. Taking into consideration the term "atypical pharmacophore" and from the compound 5, the aralkyl fragment was incorporated, and the compounds 10, 11, 13a-h and 14a-h were synthesized. Both the compounds 10 and 13a-h under its methoxylated form and the compounds 11 and 14a-h under the phenolic form, were evaluated to determine their pharmacologically agonistic and antagonistic effects on central dopaminergic activity. For this, the effect of intracerebroventricular injection of said compounds on the hydromineral balance and stereotyped behavior in rats, was determined. The results of the preliminary pharmacological evaluation show a centrally acting action through dopamine mechanisms, in which the compounds 10, 11, 13d-h and 14a showed responses as agonists, whereas compounds 14b-h, had responses as antagonists.


Asunto(s)
Agonistas de Dopamina/farmacología , Antagonistas de Dopamina/farmacología , Indanos/farmacología , Conducta Estereotipada/efectos de los fármacos , Animales , Conducta Animal/efectos de los fármacos , Agonistas de Dopamina/síntesis química , Agonistas de Dopamina/química , Antagonistas de Dopamina/síntesis química , Antagonistas de Dopamina/química , Indanos/síntesis química , Indanos/química , Inyecciones Intraventriculares , Masculino , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad
9.
Acta biol. colomb ; 20(2): 237-245, mayo-ago. 2015. ilus, tab
Artículo en Español | LILACS | ID: lil-743859

RESUMEN

Existen varios protocolos de regeneración de plantas vía embriogénesis somática de Sorghum bicolor (L.) Moench, sin embargo los porcentajes de formación de callos con estructuras embriogénicas y regeneración de plantas son bajos. Es por ello que esta investigación tuvo como objetivo generar embriones somáticos en sorgo rojo variedad CIAP 132-R. Se ensayaron diferentes concentraciones de 2,4-D para la formación de callos, así como tres concentraciones de ácido ascórbico para eliminar la exudación de compuestos fenólicos por el explante. También para la formación de los embriones somáticos a partir de los callos se evaluaron diferentes concentraciones de 2,4-D y 6-BAP. El mayor porcentaje de formación de callos (57,5 %) se alcanzó con 18,1 µM de 2,4-D. Con la adición al medio de cultivo de 50,0 mg.l-1 de ácido ascórbico fue posible eliminar los compuestos fenólicos en el explante y en el medio de cultivo, además permitió incrementar el porcentaje de formación de callos con estructuras embriogénicas hasta un 95 %. El número mayor de embriones somáticos por callo se alcanzó en el medio de cultivo con concentraciones de 4,52 µM de 2,4- D, combinada con 2,22 µM de 6-BAP. Por primera vez, se logró la formación eficiente de embriones somáticos a partir de los callos obtenidos de semillas inmaduras germinadas como explante inicial en la variedad CIAP 132-R.


Several protocols of plant regeneration via somatic embryogenesis from Sorghum bicolor (L.) Moench have been development, however the percentage of calluses with embryogenic structures and plant regeneration are low. Therefore this study aimed to generate somatic embryos in red sorghum variety CIAP 132-R. Different concentrations of 2,4-D for callus formation, and three concentrations of ascorbic acid to remove phenolics exudation were assayed by explant. For the formation of embryos different concentrations of 2,4-D and 6-BAP were evaluated. The highest percentage of callus formation (57.5 %) was achieved with 18.1 µM 2,4-D. With the addition to the culture medium of 50.0 mg.l-1 of ascorbic acid was possible to eliminate the phenolic compounds in the explant and in the culture medium; also it allows increasing the percentage of calluses with embryogenic structures up to 95 %. The highest number of somatic embryos per callus was achieved with a reduction in the culture medium of 2,4-D to 4.52 µM in combination with 2.22 µM 6-BAP. For the first time, the efficiency of somatic embryo formation was obtained from the freshly germinated sprouts of immature seeds as initial explant CIAP 132-R.

10.
Rev. colomb. biotecnol ; 14(2): 101-110, dic. 2012. ilus, tab
Artículo en Español | LILACS | ID: lil-671885

RESUMEN

El trabajo se realizó con el objetivo de obtener brotes in vitro vía organogénesis directa en sorgo variedad CIAP 2E-95, para la formación de callos con estructuras embriogénicas. Se tomaron semillas maduras de plantas que crecían en condiciones controladas, las que se desinfectaron y fueron colocadas a germinación en un medio de cultivo con las sales MS, mioinositol 100 mg L-1, sacarosa 3%, pH 5,7, Fitagel 2,5 g L-1. Para la multiplicación de los brotes, se estudiaron diferentes concentraciones de 6 Bencilaminopurina (6-BAP) y kinetina. El empleo en el medio de cultivo de multiplicación con las sales MS y 6- BAP 0,22 mg L-1, incrementó el número de brotes por explante y se observó la presencia de oxidación fenólica. La oxidación fenólica se contrarrestó con la adición al medio de cultivo de 50 mg L-1 de ácido ascórbico y se incrementó significativamente el número de brotes, altura y número de hojas. En la obtención de brotes in vitro de calidad para la formación de callos, estos fueron engrosados con las sales MS, sin reguladores de crecimiento, ácido ascórbico 50 mg L-1, Fitagel 2,5 g L-1, pH 5,7 y 40 g L-1 de sacarosa. La formación de callos con estructuras embriogénicas a partir del cilindro central de las hojas enrolladas del segmento más próximo a la base de los brotes engrosados se alcanzó a los 45 días de cultivo. Los segmentos del cilindro central de las hojas enrolladas constituyen una fuente segura y promisoria de explantes para la formación de callos embriogénicos.


The current work aimed to obtain in vitro shoots by direct organogenesis from sorghum variety CIAP 2E-95, for the formation of calluses with embryogenic structures. Mature seeds were collected from plants grown under controlled conditions, which were disinfected and were placed in a germination medium with MS salts, myo-inositol 100 mg L-1, 3% sucrose, pH 5.7, phytagel 2.5 g L-1. Different concentrations of 6-benzylaminopurine (6-BAP) and kinetin were studied for shoot multiplication. Using 6 - BAP 0.22 mg L-1 in the multiplication culture medium increased the number of shoots per explant, showing phenolic oxidation. Adding 50 mg L-1 of ascorbic acid to the culture medium resisted phenolic oxidation and the number of sprouts (5.0), height and number of leaves increased significantly. Quality in vitro buds for callus formation were obtained stimulating the thickening by using MS salts, without growth regulators, ascorbic acid 50 mg L-1, phytagel 2.5 g L-1 and pH 5.7 and 40 g L-1 of sucrose. The largest diameter of shoots, height, number of leaves and roots of in vitro plants, was achieved after 21 days of cultured in MS salts with 40 g L-1 sucrose. Calluses formation with embryogenic structures from the central cylinder of curled leaves of the nearest segment to the base of thickened shoots was achieved after 45 days of culture. Segments from the central cylinder of the curled leaves are a safe source for the formation of embryogenic calli.


Asunto(s)
Ácido Ascórbico , Plantas , Sorghum , Sacarosa , Reguladores del Crecimiento de las Plantas , Quinina
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