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2.
Biomed Pharmacother ; 153: 113489, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36076507

RESUMEN

Certain herbs used in traditional Chinese medicine may produce a growth-enhancing effect by promoting the secretion of growth hormone (GH) by the pituitary gland or mimicking the function of GH. In this study, we aimed to identify herbs that could serve as GH alternatives. A reporter gene assay for GH was developed, and 100 different herbal extracts were assayed. We found that Rhizoma Anemarrhenae (RA) water extracts exhibited transactivation activities that stimulate the activation of signal transducer and activator of transcription 5 (STAT5). The growth-promoting effect of RA in NB2-11 cells was inhibited by co-treatment with GH receptor (GHR)-Fc fusion protein. Unlike GH, RA extracts did not enhance the growth of B16F10 melanoma cells. The activation of the Janus kinase 2-STAT5 signaling pathway was confirmed in both NB2-11 cells and WI-38 human normal lung fibroblasts; the activation was inhibited by co-treatment with GHR-Fc fusion protein. Docking analysis of the active ingredients of RA, including mangiferin, neomangiferin, isomangiferin, anemarsaponin E, 7-O-methylmangiferin, officinalisinin I, timosaponin BII, timosaponin AI, and timosaponin AIII, using SWISSDOCK indicated a direct interaction of these compounds with GHR. The growth-promoting effects and activation of STAT5 were also confirmed. Moreover, we found that RA extract significantly increased the height of the tibial growth plate and stimulated the production of insulin-like growth factor 1 in the serum, liver, and muscle tissues. Our findings provide evidence that herbal extracts, particularly, RA extracts, can promote growth by mimicking GH bioactivity.


Asunto(s)
Anemarrhena , Medicamentos Herbarios Chinos , Hormona del Crecimiento , Medicamentos Herbarios Chinos/farmacología , Hormona del Crecimiento/farmacología , Humanos , Receptores de Somatotropina/genética , Receptores de Somatotropina/metabolismo , Factor de Transcripción STAT5/metabolismo
3.
Toxicon ; 217: 143-147, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-35987354

RESUMEN

In Taiwan, Trimeresurus stejnegeri stejnegeri (Stejneger's Bamboo pitviper) is responsible for more than half of all venomous snakebites annually. This species often causes local envenoming characterized by tissue swelling and pain, occasional local ecchymosis, bullae and blister formation, and lymphangitis and lymphadenitis. The pathophysiology and treatment of potentially life-threatening coagulopathy and defibrinogenation induced by T. s. stejnegeri systemic envenoming have not been specifically addressed. Here, we describe the case of a man who was bitten by T. s. stejnegeri on his right first toe, which later developed into swelling above the ankle. It was found that there was severe hypofibrinogenemia, prolonged prothrombin time, and reduced activities of factors V and XI, plasminogen, and α2-antiplasmin. Even though a favorable outcome was achieved after repeatedly administering specific antivenom, fresh frozen plasma, and cryoprecipitate, probably low effectiveness of antivenom against the coagulopathy and prodigious amounts of replacement products were observed. To control coagulopathy early and avoid the needless replacement of coagulation factor, which are associated with inherent adverse reactions, more frequent serial blood assessment (e.g., every 6 h) and higher initial antivenom doses may be helpful. Knowledge of the specific coagulation factor deficiencies may improve our understanding of the relationship between hemotoxins and the resulting envenoming syndromes in this snakebite.


Asunto(s)
Trastornos de la Coagulación Sanguínea , Mordeduras de Serpientes , Trimeresurus , Animales , Tobillo , Antivenenos/uso terapéutico , Antivenenos/toxicidad , Trastornos de la Coagulación Sanguínea/inducido químicamente , Factores de Coagulación Sanguínea/uso terapéutico , Factores de Coagulación Sanguínea/toxicidad , Edema/inducido químicamente , Humanos , Mordeduras de Serpientes/tratamiento farmacológico
4.
PLoS Negl Trop Dis ; 16(2): e0010066, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35143522

RESUMEN

BACKGROUND: Naja atra bites cause wound necrosis, secondary infection, and necrotizing soft tissue infection (NSTI) requiring repetitive surgeries. Little information is known about the predictors for surgery after these bites. MATERIALS AND METHODS: We retrospectively evaluated 161 patients envenomed by N. atra, 80 of whom underwent surgery because of wound necrosis and infection. We compared the patients' variables between surgical and non-surgical groups. To construct a surgical risk score, we converted the regression coefficients of the significant factors in the multivariate logistic regression into integers. We also examined the deep tissue cultures and pathological findings of the debrided tissue. RESULTS: A lower limb as the bite site, a ≥3 swelling grade, bullae or blister formation, gastrointestinal (GI) effects, and fever were significantly associated with surgery in the multivariate logistic regression analysis. The surgical risk scores for these variables were 1, 1, 2, 1, and 2, respectively. At a ≥3-point cutoff value, the model has 71.8% sensitivity and 88.5% specificity for predicting surgery, with an area under the receiver operating characteristic curve of 0.88. The histopathological examinations of the debrided tissues supported the diagnosis of snakebite-induced NSTI. Twelve bacterial species were isolated during the initial surgery and eleven during subsequent surgeries. DISCUSSION AND CONCLUSIONS: From the clinical perspective, swelling, bullae or blister formation, GI effects, and fever appeared quickly after the bite and before surgery. The predictive value of these factors for surgery was acceptable, with a ≥3-point risk score. The common laboratory parameters did not always predict the outcomes of N. atra bites without proper wound examination. Our study supported the diagnosis of NSTI and demonstrated the changes in bacteriology during the surgeries, which can have therapeutic implications for N. atra bites.


Asunto(s)
Naja naja , Mordeduras de Serpientes/complicaciones , Mordeduras de Serpientes/cirugía , Infecciones de los Tejidos Blandos/cirugía , Adulto , Animales , Bacterias/aislamiento & purificación , Venenos Elapídicos , Fascitis Necrotizante/complicaciones , Fascitis Necrotizante/microbiología , Fascitis Necrotizante/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Mordeduras de Serpientes/terapia , Infecciones de los Tejidos Blandos/complicaciones , Infecciones de los Tejidos Blandos/microbiología
5.
Toxins (Basel) ; 13(9)2021 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-34564623

RESUMEN

Patients bitten by Naja atra who are treated with bivalent freeze-dried neurotoxic antivenom in Taiwan have an improved survival rate but develop necrotic wound changes. The World Health Organization (WHO) has suggested using the minimum necrotizing dose (MND) of venom as a method of evaluating the neutralization effect of antivenom. The aim of this study was to evaluate the effectiveness of antivenom for the prevention of necrosis based on the MND and clarify which component of the venom of N. atra induces necrosis. The neurotoxins (NTXs) were removed from the crude venom (deNTXs), and different concentrations of deNTXs were injected intradermally into the dorsal skin of mice. After three days, the necrotic lesion diameter was found to be approximately 5 mm, and the MND was calculated. A reduction in the necrotic diameter of 50% was used to identify the MND50. Furthermore, both phospholipase A2 (PLA2) and cytotoxins (CTXs) were separately removed from the deNTXs to identify the major necrosis-inducing factor, and the necrotic lesions were scored. All mice injected with deNTXs survived for three days and developed necrotic wounds. The MND of the deNTXs for mice was 0.494 ± 0.029 µg/g, that of the deNTXs-dePLA2 (major component retained: CTXs) was 0.294 ± 0.05 µg/g, and that of the deNTX-deCTX (major component retained: PLA2) venom was greater than 1.25 µg/g. These values show that CTX is the major factor inducing necrosis. These results suggest that the use of the deNTXs is necessary to enable the mice to survive long enough to develop venom-induced cytolytic effects. CTXs play a major role in N. atra-related necrosis. However, the MND50 could not be identified in this study, which meant that the antivenom did not neutralize venom-induced necrosis.


Asunto(s)
Antivenenos/farmacología , Venenos Elapídicos/toxicidad , Naja naja , Necrosis/tratamiento farmacológico , Animales , Liofilización , Masculino , Ratones , Necrosis/inducido químicamente
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