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1.
Rev Chil Pediatr ; 90(3): 309-315, 2019 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-31344191

RESUMO

INTRODUCTION: The early diagnosis of Sleep Disordered Breathing (SDB) may allow proper intervention. Currently, polygraphy (PG) is a reliable and accessible alternative. OBJECTIVE: To describe and analyze the PG of children > 1 year old with suspicion of SDB. PATIENTS AND METHOD: PG of children > 1 year old and adolescents from Concepcion, Chile, with suspected SDB were included, from December 2011 to Au gust 2017. Demographic, clinical and polygraphic variables were collected. It was used descriptive sta tistics, expressing results in median and range. The association between apnea-hypopnea index (AHI) and oxygen saturation was determined by Spearman's Rho, considering significance of p < 0.05. Re sults: 190 studies were analyzed. Age 7.9 years old (1.0-20.6), 61% males. DIAGNOSIS: neuromuscular disease (NMD) (24.2%), chronic lung damage (21.1%), upper airway obstruction (UAO) (19.5%), neurological damage (11%), Down syndrome (8.9%), upper airway malformations (7.4%), central hypoventilation (3.7%), obesity (2.6%), and others (1.6%). 55.3% were altered PG, with 53.3% of mild Obstructive Sleep Apnea Hypopnea Syndrome (OSAHS), 30.5% moderate, and 16.2% severe. There were no significant differences in AHI between groups of pathologies (p = 0.032), highlighting a higher AHI in obese patients 9 (0.41-51), and those with NMD 23.9 (0.4-36.6). It was found asso ciation between AHI and oxygen saturation parameters: mean saturation (rho = -0.425; p = 0.001), minimum (rho = -0.654; p = 0.001), and oxygen saturation below 90% (rho = 0.323; p = 0.001) in the whole sample. DISCUSSION: There was a high percentage of OSAHS in at-risk pediatric patients, especially in those with NMD and obesity. PG is an accessible and implementable tool in a public hospital, a situation that can potentially be extrapolated to other healthcare centers.


Assuntos
Polissonografia/métodos , Síndromes da Apneia do Sono/diagnóstico , Apneia Obstrutiva do Sono/diagnóstico , Adolescente , Criança , Pré-Escolar , Chile/epidemiologia , Feminino , Humanos , Lactente , Masculino , Doenças Neuromusculares/epidemiologia , Oxigênio/metabolismo , Obesidade Infantil/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Síndromes da Apneia do Sono/epidemiologia , Apneia Obstrutiva do Sono/epidemiologia
2.
J Am Chem Soc ; 138(23): 7315-24, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27172766

RESUMO

A palladium-catalyzed multicomponent synthetic route to polysubstituted pyrroles from aryl iodides, imines, carbon monoxide, and alkynes is described. To develop this reaction, a series of mechanistic studies on the [Pd(allyl)Cl]2/P(t)Bu3 catalyzed synthesis of imidazolinium carboxylates from aryl iodides, imines, and carbon monoxide were first performed, including model reactions for each individual step in the transformation. These show that this reaction proceeds in a concurrent tandem catalytic fashion, and involves the in situ formation of acid chlorides, N-acyl iminium salts, and ultimately 1,3-dipoles, i.e., Münchnones, for subsequent cycloaddition. By employing a Pd(P(t)Bu3)2/Bu4NCl catalyst, this information was used to design the first four-component synthesis of Münchnones. Coupling the latter with 1,3-dipolar cycloaddition with electron deficient alkynes or alkenes can be used to generate diverse families of highly substituted pyrroles in good yield. This represents a modular and streamlined new approach to this class of heterocycles from readily accessible starting materials.

3.
Chemistry ; 22(42): 15107-15118, 2016 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-27608423

RESUMO

We describe herein computational studies on the unusual ability of Pd(PtBu3 )2 to catalyze formation of highly reactive acid chlorides from aryl halides and carbon monoxide. These show a synergistic role of carbon monoxide in concert with the large cone angle PtBu3 that dramatically lowers the barrier to reductive elimination. The tertiary structure of the phosphine is found to be critical in allowing CO association and the generation of a high energy, four coordinate (CO)(PR3 )Pd(COAr)Cl intermediate. The stability of this complex, and the barrier to elimination, is highly dependent upon phosphine structure, with the tertiary steric bulk of PtBu3 favoring product formation over other ligands. These data suggest that even difficult reductive eliminations can be rapid with CO association and ligand manipulation. This study also represents the first detailed exploration of all the steps involved in palladium-catalyzed carbonylation reactions with simple phosphine ligands, including the key rate-determining steps and palladium(0) catalyst resting state in carbonylations.

4.
J Org Chem ; 81(22): 11145-11152, 2016 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-27726363

RESUMO

A palladium-catalyzed multicomponent route to polycyclic pyrroles is described. Pd(PtBu3)2 was found to catalyze the coupling of (hetero)aryl iodides, two equivalents of carbon monoxide and alkyne-tethered imines into 1,3-dipoles (Münchnones), which undergo spontaneous, intramolecular 1,3-dipolar cycloaddition to form polycyclic pyrroles. The systematic variation of the alkyne, tethered-imine, or aryl iodide can allow the buildup of a range of pyrrole derivatives, where any of the substituents can be independently varied. In addition, the same palladium catalyst can be employed in an initial Sonogashira-type coupling with aryl iodides, which upon the addition of CO can allow the novel tandem catalytic, five component synthesis of diversely substituted products.

5.
J Org Chem ; 81(24): 12106-12115, 2016 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-27978726

RESUMO

A palladium-catalyzed multicomponent method for the synthesis of ß-lactams from imines, aryl halides, and CO has been developed. This transformation proceeds via two tandem catalytic carbonylation reactions mediated by Pd(PtBu3)2 and provides a route to prepare these products from five separate reagents. A diverse range of polysubstituted ß-lactams can be generated by systematic variation of the substrates. This methodology can also be extended to the use of iodo-substituted imines to produce novel spirocyclic ß-lactams in good yields and selectivity.

6.
Plants (Basel) ; 13(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38475490

RESUMO

In the pursuit of identifying the novel resin glycoside modulators glucose-6-phosphatase and α-glucosidase enzymes, associated with blood sugar regulation, methanol-soluble extracts from the flowers of Ipomoea murucoides (cazahuate, Nahuatl), renowned for its abundance of glycolipids, were employed. The methanol-soluble extracts were fractionated by applying the affinity-directed method with glucose-6-phosphatase enzymes from a rat's liver and α-glucosidase enzymes from its intestines. Mass spectrometry and nuclear magnetic resonance were employed to identify the high-affinity compound as a free ligand following the release from the enzymatic complex. Gel permeation through a spin size-exclusion column allowed the separated high-affinity molecules to bind to glucose-6-phosphatase and α-glucosidase enzymes in solution, which led to the identification of some previously reported resin glycosides in the flowers of cazahuate, where a glycolipid mainly structurally related to murucoidin XIV was observed. In vitro studies demonstrated the modulating properties of resin glycosides on the glucose-6-phosphatase enzyme. Dynamic light scattering revealed conformational variations induced by resin glycosides on α-glucosidase enzyme, causing them to become more compact, akin to observations with the positive control, acarbose. These findings suggest that resin glycosides may serve as a potential source for phytotherapeutic agents with antihyperglycemic properties.

7.
Rev Biol Trop ; 61(3): 1067-81, 2013 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-24027908

RESUMO

Studies on some reproductive traits in Equisetum species are scarce and valuable to understand species distribution. Therefore, a detailed study of the sporogenesis process and spore development in E. bogotense is presented, with an analysis of the main events during meiosis, maturation of spores, spore wall ultrastructure, orbicules and elaters. Specimens were collected from 500 to 4500 m in Cauca, Colombia. Strobili at different maturation stages were fixed, dehydrated, embedded in resin, and ultra-microtome obtained sections were stained with Toluidine blue. Observations were made with optical microscopy with differential interference contrast illumination technique (DIC), transmission and scanning electron microscopy (TEM and SEM). Ultrathin sections (70-80 microm) for TEM observations were stained with uranyl acetate and lead citrate; while samples for SEM observations, were fixed, dehydrated in 2.2-dimethoxypropane and dried at critical point as in standard methods. Strobili have numerous mature sporangiophores, each one with a peltate structure, the scutellum, bearing five-six sessile sporangia attached to the axis of strobilus by the manubrium. Immature sporocytes (spore mother cells) are tightly packed within the young sporangia. The sporocytes quickly undergo meiosis, by passing the stage of archesporium and give origin to tetrads of spores. The tapetum loses histological integrity during early stages of sporogenesis, intrudes as a plasmodial mass into the cavity of the sporangium, partially surrounding premeiotic sporocytes, and then, tetrads and adult spores. The tapetum disintegrates towards the end of the sporogenesis, leaving spores free within the sporangial cavity. Spores present several cytological changes that allow them to achieve greater size and increase the number of plastids, before reaching the adult stage. Sporoderm includes three layers external to the cytoplasmic membrane of the spore cell, and they are pseudoendospore, exospore and perispore. Viewed with SEM, the exospore is smooth to rugulate, with micro perforations, while the perispore is muriform, rugate, with narrow, delicate, discontinuous, randomly distributed folds delimiting incomplete, irregular areolae, externally covered by of different size, densely distributed orbicules. These orbicules are also found all over the external face and margins of the elaters, while the internal face is smooth and lack orbicules. Viewed with TEM, the exospore is a thick layer of fine granular material, while perispore is a thinner layer of dense, separate orbicules. The elaters are composed by two layers of fibrillar material: an inner layer with longitudinally oriented fibrils and an outer, thicker and less dense layer with fibrils transversely fibrils and abundant, external orbicules. It is suggested that the processes of ontogeny and characters of the sporoderm are relatively constant in Equisetum; however, sporogenesis in E. bogotense is synchronous and this condition has been observed so far only in E. giganteum, a tropical genus also found in Colombia.


Assuntos
Equisetum/ultraestrutura , Esporângios/ultraestrutura , Esporos/ultraestrutura , Colômbia , Equisetum/classificação , Equisetum/embriologia , Esporângios/embriologia , Esporos/crescimento & desenvolvimento
8.
Cureus ; 15(10): e46635, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37936989

RESUMO

Tolosa-Hunt syndrome (THS) is an idiopathic inflammatory condition involving the cavernous sinus and orbital apex with an incidence of 1 case per million per year. We report on a case of a 70-year-old male with atypical MRI findings, vision loss, and painless ophthalmoplegia.  Ophthalmic evaluation revealed his best-corrected visual acuity was 20/40 in the right eye and counting fingers at a 0.5-foot distance in the left eye. External examination of the left eye revealed limited ocular movement, proptosis, and a positive relative afferent pupillary defect. Complete blood count, inflammatory markers, and full biochemistry tests, including thyroid and liver function tests, were within the normal range. A magnetic resonance imaging of the orbits with and without contrast demonstrated a homogenously enhancing lesion at the posterior intraconal compartment of the left orbit, extending to the orbital apex with the involvement of the adjacent extraocular muscles. The patient was started on intravenous methylprednisolone 60 mg daily and later discharged on prednisone 5 mg daily with partial symptom improvement on follow-up. Resection and biopsy revealed a soft tissue lesion with mixed inflammatory infiltrate. The clinical, pathological, and imaging findings favored the diagnosis of THS.

9.
Sci Rep ; 13(1): 8975, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37268683

RESUMO

Our knowledge of traumatic brain injury has been fast growing with the emergence of new markers pointing to various neurological changes that the brain undergoes during an impact or any other form of concussive event. In this work, we study the modality of deformations on a biofidelic brain system when subject to blunt impacts, highlighting the importance of the time-dependent behavior of the resulting waves propagating through the brain. This study is carried out using two different approaches involving optical (Particle Image Velocimetry) and mechanical (flexible sensors) in the biofidelic brain. Results show that the system has a natural mechanical frequency of [Formula: see text] 25 oscillations per second, which was confirmed by both methods, showing a positive correlation with one another. The consistency of these results with previously reported brain pathology validates the use of either technique, and establishes a new, simpler mechanism to study brain vibrations by using flexible piezoelectric patches. The visco-elastic nature of the biofidelic brain is validated by observing the the relationship between both methods at two different time intervals, by using the information of the strain and stress inside the brain from the Particle Image Velocimetry and flexible sensor, respectively. A non-linear stress-strain relationship was observed and justified to support the same.


Assuntos
Concussão Encefálica , Lesões Encefálicas Traumáticas , Humanos , Vibração , Encéfalo , Cabeça
10.
Alzheimers Dement (Amst) ; 15(1): e12398, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36777092

RESUMO

Apathy is one of the most common neuropsychiatric symptoms (NPS) and is associated with poor clinical outcomes. Research that helps define the apathy phenotype is urgently needed, particularly for clinical and biomarker studies. We used latent class analysis (LCA) with two independent cohorts to understand how apathy and depression symptoms co-occur statistically. We further explored the relationship between latent class membership, demographics, and the presence of other NPS. The LCA identified a four-class solution (no symptoms, apathy, depression, and combined apathy/depression), reproducible over both cohorts, providing robust support for an apathy syndrome distinct from depression and confirming that an apathy/depression syndrome exists, supported by the model fit test with the four-class solution scores evidencing better fitting (Bayesian information criterion adjusted and entropy R 2). Using a data-driven method, we show distinct and statistically meaningful co-occurrence of apathy and depressive symptoms. There was evidence that these classes have different clinical associations, which may help inform diagnostic categories for research studies and clinical practice. Highlights: We found four classes: no symptoms, apathy, depression and apathy/depression.Apathy conferred a higher probability for agitation.Apathy diagnostic criteria should include accompanying neuropsychiatric symptoms.

11.
Cureus ; 14(1): e21015, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35028241

RESUMO

Introduction COVID-19 is an emerging disease and the neurotologic symptoms are still not well understood. Furthermore, the development of a neurotological profile and its associated factors can help the clinician in the diagnosis and treatment of this disease. The objective is to determine the neurotologic manifestations experienced by COVID-19 positive health care workers and their associated factors. Methods A symptoms survey was administered to health care workers who were positive to COVID-19 from September to October 2020. An informed consent form was digitally signed and Google Forms software was used for the survey. Frequencies and percentages were used for categorical variables, and associated clinical features were reported with odds ratios. Results We included 209 COVID-19 positive health care workers, 55.5% (n = 116) were women, and 44.5% (n = 93) were men. Fifty-three percent of patients were 20 to 30 years old and 56.4% had at least one comorbidity. The prevalence of neurotological manifestations was 18.6% (n = 39/209), the most frequent symptoms were vertigo (61.5%, n = 24/39), tinnitus (43.5%, n = 17/39), imbalance (43.5%, n = 17/39), and one case of facial paralysis (2.5%, n = 1/39). Neurotological manifestations were associated predominantly with asthenia (p = 0.021), loss of smell (p = 0.002) and taste dysfunction (p = 0.002). Conclusion The most common neurotological manifestations were vertigo, tinnitus and imbalance. Clinical features associated with a neurotologic profile were asthenia, hyposmia and dysgeusia.

12.
Waste Manag ; 139: 279-289, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34995855

RESUMO

This study aimed to establish the optimal operational conditions for hydrogen production using vermicomposting-tea and sugarcane molasses as substrate. The experiments were carried out by triplicate in 110 ml serological bottles, a Box-Behnken design of experiments was performed in anaerobic dark conditions. The maximal hydrogen production (HP), hydrogen production rate (HPR), and hydrogen yield (HY) attained were 1021.0 mlL-1, 5.32 mlL-1h-1, and 60.3 mlLH2-1/gTCC, respectively. The statistical model showed that the optimal operational conditions for pH, molasses concentration, and temperature were 6.5; 30 % (v/v) and 25 °C. The bioreactor run showed 17.202 L of hydrogen, 0.58 Lh-1, and 77.2 mlH2gTCC-1 For HP, HPR, and HY. Chemometric analysis for the volatile fatty acids obtained at the fermentation showed that only two principal components are required to explain 90 % of the variance. The representative pathways for hydrogen production were acetic and butyric acids. This study established the operational conditions for the upstream processing amenable to pilot and industrial-scale operations. Our results add value to molasses within the circular economy for hydrogen production using a novel consortium from vermicompost.


Assuntos
Hidrogênio , Melaço , Reatores Biológicos , Quimiometria , Fermentação , Hidrogênio/análise , Concentração de Íons de Hidrogênio , Chá
13.
Sci Rep ; 12(1): 3110, 2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-35210481

RESUMO

Diabetic foot syndrome, a long term consequence of Diabetes Mellitus, is the most common cause of non-traumatic amputations. Around 8% of the world population suffers from diabetes, 15% of diabetic patients present a diabetic foot ulcer which leads to amputation in 2.5% of the cases. There is no objective method for the early diagnosis and prevention of the syndrome and its consequences. We test terahertz imaging, which is capable of mapping the cutaneous hydration, for the evaluation of the diabetic foot deterioration as an early diagnostic test as well as ulcers prevention and tracking tool. Furthermore, the analysis of our terahertz measurements combined with neurological and vascular assessment of the patients indicates that the dehydration is mainly related to the peripheral neuropathy without a significant vascular cause.


Assuntos
Pé Diabético/diagnóstico por imagem , Nefropatias Diabéticas/fisiopatologia , Imagem Terahertz/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Desidratação/fisiopatologia , Pé Diabético/fisiopatologia , Nefropatias Diabéticas/diagnóstico por imagem , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , Doenças do Sistema Nervoso Periférico , Fatores de Risco , Pele/metabolismo
14.
Tetrahedron ; 67(5): 830-836, 2011 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-21311601

RESUMO

A substrate-controlled stereoselective epoxidation of free and monoprotected homoallylic diols was developed. This second-generation approach is based on the incorporation of a primary hydroxy directing group at the C2 methyl carbon, which changes the nature of the vanadium ester intermediate providing a new diastereoselectivity manifold for the preparation of 3,4-epoxy alcohols. This modification favored the formation of the challenging C2-syn epoxy alcohol product not previously available using the standard homoallylic alcohol substrates. These new epoxy alcohol diastereomers expand the scope and generality for the utilization of 3,4-epoxy alcohols as precursors for stereoselective polypropionate synthesis.

15.
Rev Biol Trop ; 59(4): 1845-58, 2011 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-22208097

RESUMO

Studies on the ontogeny of the strobilus, sporangium and reproductive biology of this group of ferns are scarce. Here we describe the ontogeny of the strobilus and sporangia, and the process of sporogenesis using specimens of E. giganteum from Colombia collected along the Rio Frio, Distrito de Sevilla, Piedecuesta, Santander, at 2200m altitude. The strobili in different stages of development were fixed, dehydrated, embedded in paraffin, sectioned using a rotatory microtome and stained with the safranin O and fast green technique. Observations were made using differential interference contrast microscopy (DIC) or Nomarski microscopy, an optical microscopy illumination technique that enhances the contrast in unstained, transparent. Strobili arise and begin to develop in the apical meristems of the main axis and lateral branches, with no significant differences in the ontogeny of strobili of one or other axis. Successive processes of cell division and differentiation lead to the growth of the strobilus and the formation of sporangiophores. These are formed by the scutellum, the manubrium or pedicel-like, basal part of the sporangiophore, and initial cells of sporangium, which differentiate to form the sporangium wall, the sporocytes and the tapetum. There is not formation of a characteristic arquesporium, as sporocytes quickly undergo meiosis originating tetrads of spores. The tapetum retains its histological integrity, but subsequently the cell walls break down and form a plasmodium that invades the sporangial cavity, partially surrounding the tetrads, and then the spores. Towards the end of the sporogenesis the tapetum disintegrates leaving spores with elaters free within the sporangial cavity. Two layers finally form the sporangium wall: the sporangium wall itself, with thickened, lignified cell walls and an underlying pyknotic layer. The mature spores are chlorofilous, morphologically similar and have exospore, a thin perispore and two elaters. This study of the ontogeny of the spore-producing structures and spores is the first contribution of this type for a tropical species of the genus. Fluorescence microscopy indicates that elaters and the wall of the sporangium are autofluorescent, while other structures induced fluorescence emitted by the fluorescent dye safranin O. The results were also discussed in relation to what is known so far for other species of Equisetum, suggesting that ontogenetic processes and structure of characters sporoderm are relatively constant in Equisetum, which implies important diagnostic value in the taxonomy of the group.


Assuntos
Equisetum/citologia , Esporângios/citologia , Esporos/crescimento & desenvolvimento , Colômbia , Equisetum/crescimento & desenvolvimento , Meiose , Esporângios/crescimento & desenvolvimento
16.
Front Pharmacol ; 12: 809994, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35002743

RESUMO

Liver plays a pivotal role in maintaining blood glucose levels through complex processes which involve the disposal, storage, and endogenous production of this carbohydrate. Insulin is the hormone responsible for regulating hepatic glucose production and glucose storage as glycogen, thus abnormalities in its function lead to hyperglycemia in obese or diabetic patients because of higher production rates and lower capacity to store glucose. In this context, two different but complementary therapeutic approaches can be highlighted to avoid the hyperglycemia generated by the hepatic insulin resistance: 1) enhancing insulin function by inhibiting the protein tyrosine phosphatase 1B, one of the main enzymes that disrupt the insulin signal, and 2) direct regulation of key enzymes involved in hepatic glucose production and glycogen synthesis/breakdown. It is recognized that medicinal plants are a valuable source of molecules with special properties and a wide range of scaffolds that can improve hepatic glucose metabolism. Some molecules, especially phenolic compounds and terpenoids, exhibit a powerful inhibitory capacity on protein tyrosine phosphatase 1B and decrease the expression or activity of the key enzymes involved in the gluconeogenic pathway, such as phosphoenolpyruvate carboxykinase or glucose 6-phosphatase. This review shed light on the progress made in the past 7 years in medicinal plants capable of improving hepatic glucose homeostasis through the two proposed approaches. We suggest that Coreopsis tinctoria, Lithocarpus polystachyus, and Panax ginseng can be good candidates for developing herbal medicines or phytomedicines that target inhibition of hepatic glucose output as they can modulate the activity of PTP-1B, the expression of gluconeogenic enzymes, and the glycogen content.

17.
Artigo em Inglês | MEDLINE | ID: mdl-33505497

RESUMO

The onset of type 2 diabetes (T2D) is a consequence of the progressive loss of adequate ß-cell insulin secretion, which frequently occurs under a background of insulin resistance. Currently, nearly 13 million Mexicans are living with diabetes. Moreover, due to poor socioeconomic conditions and the cultural idiosyncrasies of the Mexican population, the use of medicinal plants to treat T2D is a common practice in Mexico. In the Mexican state of Hidalgo, we found the traditional use of Calea urticifolia (CU) to treat this disease. To treat T2D, people drink an infusion made from the aerial part of the plant throughout the day. With the aim of investigating whether the infusion at a traditional dose produces a hypoglycemic effect in either the fasting or postprandial state, we measured the effect of the infusion in a hyperglycemic animal model (rats administered streptozotocin (STZ) and nicotinamide (NZ)) by conducting a glucose tolerance test and constructing a blood-glucose curve. We then analyzed whether the observed effect was related to the inhibition of glucose absorption in the gut or the inhibition of hepatic glucose output (HGO) in vivo and in vitro. Furthermore, we confirmed our findings by identifying the potential targets of the infusion via a network pharmacology analysis. Through high-performance liquid chromatography (HPLC) and thin layer chromatography (TLC), we detected a number of compounds in the extract and identified two of them. The plant extract produced a highly significant hypoglycemic effect under fasting conditions and a weak hypoglycemic effect following glucose or sucrose challenge. Although the plant extract blocked only 20% of the alpha-glucosidase enzyme activity in vitro, in the pyruvate tolerance test (which measures the liberation of hepatic glucose), it significantly reduced glucose levels. Furthermore, in vitro, the extract diminished the activity of the glucose-6-phosphatase complex by 90%. In addition, by conducting TLC, we detected the presence of chlorogenic acid and rutin, which have been reported to block HGO. The results presented here provide evidence of the hypoglycemic effect of the traditionally used C. urticifolia extract and demonstrate that this effect is associated with both a reduction in glucose synthesis via gluconeogenesis due to the phytochemical composition of the extract and a slight blockage of glucose absorption in the gut.

18.
Plants (Basel) ; 10(10)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34685869

RESUMO

Type 2 diabetes is a worldwide prevalent disease that is due to a progressive loss of adequate ß-cell insulin secretion, frequently against a background of insulin resistance. In Mexican traditional medicine, the therapeutic use of hypoglycemic plants to control the disease is a common practice among type 2 diabetic patients. In the present work, we examined the traditional use of the aerial parts of Eryngium longifolium and the rhizome of Alsophila firma, consumed by people use over the day (in fasting state) to control their blood glucose levels, therefore, we aimed to assess the acute hypoglycemic effect of both plants. First, basic phytochemical profiles of both plants were determined and, subsequently, acute toxicity tests were carried out. Then, in vivo hypoglycemic tests were performed in streptozotocin-nicotinamide (STZ-NA) induced hyperglycemic Wistar rats and finally the effect of the plants on three enzymes involved in glucose metabolism was assayed in vitro. Through HPLC-DAD chromatography, caffeic acid, chlorogenic acid, rosmarinic acid, isoflavones, and glycosylated flavonoids were identified in E. longifolium, while the possible presence of flavanones or dihydroflavonols was reported in A. firma. Both plants exhibited a statistically significant hypoglycemic effect, without a dose-dependent effect. Furthermore, they inhibited glucose 6-phosphatase and fructose 1,6-bisphosphatase in in vitro assays, which could be associated with the hypoglycemic effect in vivo. Thus, this study confirmed for the first time the traditional use of the aerial part of E. longifolium and the rhizome of A. firma as hypoglycemic agents in a hyperglycemic animal model. In addition, it was concluded that their ability to regulate hyperglycemia could involve the inhibition of hepatic glucose output, which mainly controls glucose levels in the fasting state.

19.
J Ethnopharmacol ; 279: 114339, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34166734

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Eryngium cymosum F. Delaroche was detected as a traditional remedy against type 2 diabetes consumed by patients of Tlanchinol in the state of Hidalgo, Mexico. AIM OF THE STUDY: Assessing the hypoglycemic effect and safety of the traditional extract of E. cymosum and relating it to key glucose-lowering mechanisms both in fasting and postprandial state. MATERIALS AND METHODS: The aqueous extract of E. cymosum was subjected to HPLC analysis to identify its main components. Hyperglycaemic STZ-NA Wistar rats were administered with the extract to evaluate its effect on blood glucose levels and a possible dose-dependence. Afterward, it was evaluated in both pyruvate and maltose tolerance tests in STZ-NA rats to characterize its effect on gluconeogenesis and carbohydrate breakdown, two of the main mechanisms responsible for fasting and postprandial hyperglycaemia in type 2 diabetes patients. In addition, the inhibitory capacity of the extract was evaluated on key enzymes involved in gluconeogenesis and a-glucosidases. Moreover, insulin concentrations were measured in normoglycemic rats in both conditions to establish a link between the hypoglycaemic effect of the extract with insulin release and functioning. RESULTS: Caffeic acid (1), chlorogenic acid (2), and rosmarinic acid (3) were identified as the main constituents of the aqueous extract of E. cymosum, which exerted a hypoglycaemic effect in hyperglycaemic STZ-NA rats. It has a significant antihyperglycemic effect in the pyruvate tolerance test, and it was able to reduce the postprandial hyperglycaemia in maltose tolerance tests significantly. Moreover, it effectively reduced the activity of both gluconeogenic enzymes reaching almost 100% of inhibition, while it presented a modest 32% inhibition of aglucosidases. On the other hand, the extract decreased insulin levels after its oral administration in healthy rats in both nutritional states, without affecting normoglycemia in normal curves and reducing the postprandial peak in glucose load curves. CONCLUSIONS: The traditional consumed form of aerial parts of E. cymosum is safe and regulated glucose levels both in fasting and in postprandial state.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Eryngium/química , Hipoglicemiantes/farmacologia , Extratos Vegetais/farmacologia , Animais , Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Jejum , Gluconeogênese/efeitos dos fármacos , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/isolamento & purificação , Insulina/sangue , México , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/isolamento & purificação , Ratos , Ratos Wistar
20.
BMC Med Genet ; 11: 19, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-20122163

RESUMO

BACKGROUND: Fabry disease (FD), an X-linked lysosomal storage disorder, is caused by a reduced activity of the lysosomal enzyme alpha-galactosidase A. The disorder ultimately leads to organ damage (including renal failure) in males and females. However, heterozygous females usually present a milder phenotype with a later onset and a slower progression. METHODS: A combined enzymatic and genetic strategy was used, measuring the activity of alpha-galactosidase A and genotyping the alpha-galactosidase A gene (GLA) in dried blood samples (DBS) of 911 patients undergoing haemodialysis in centers across Spain. RESULTS: GLA alterations were found in seven unrelated patients (4 males and 3 females). Two novel mutations (p.Gly346AlafsX347 and p.Val199GlyfsX203) were identified as well as a previously described mutation, R118C. The R118C mutation was present in 60% of unrelated patients with GLA causal mutations. The D313Y alteration, considered by some authors as a pseudo-deficiency allele, was also found in two out of seven patients. CONCLUSIONS: Excluding the controversial D313Y alteration, FD presents a frequency of one in 182 individuals (0.55%) within this population of males and females undergoing haemodialysis. Moreover, our findings suggest that a number of patients with unexplained and atypical symptoms of renal disease may have FD. Screening programmes for FD in populations of individuals presenting severe kidney dysfunction, cardiac alterations or cerebrovascular disease may lead to the diagnosis of FD in those patients, the study of their families and eventually the implementation of a specific therapy.


Assuntos
Doença de Fabry/genética , alfa-Galactosidase/genética , Adulto , Idoso de 80 Anos ou mais , Alelos , Substituição de Aminoácidos , Doença de Fabry/enzimologia , Doença de Fabry/epidemiologia , Feminino , Genótipo , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Fenótipo , Diálise Renal , Espanha , alfa-Galactosidase/metabolismo
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