RESUMEN
BACKGROUND: Although the COVID-19 pandemic has increased the prevalence of cases with olfactory loss, other respiratory viruses can also cause this condition. We aimed to compare the prevalence of acute SARS-CoV-2 infection and other respiratory viruses in patients with sudden smell loss, and to assess the impact of SARS-CoV-2 viral load and co-infection on olfactory symptoms. METHODS: Patients with sudden smell loss were recruited in a multicenter prospective cohort study in 15 hospitals in Brazil. Clinical questionnaire, Connecticut Chemosensory Clinical Research Center (CCCRC) olfactory test and nasopharyngeal swab to perform a PCR-based respiratory viral panel were collected at first visit (day 0) and 30 and 60 days after recruitment. RESULTS: 188 of 213 patients presented positive test result for SARS-CoV-2, among which 65 were co-infected with other respiratory viruses (e.g., rhinovirus, enterovirus, and parainfluenza). 25 had negative test results for SARS-CoV-2. Patients in both SARSCoV-2 and non-SARS-CoV-2 groups had objective anosmia (less than 2 points according to the psychophysical olfactory CCCRC) at day 0, with no significant difference between them. Both groups had significant smell scores improvement after 30 and 60 days, with no difference between them. Co-infection with other respiratory viruses, and SARS-CoV-2 viral load did not impact olfactory scores. CONCLUSION: Patients with sudden smell loss associated with SARS-CoV-2 and other respiratory viruses had similar presentation, with most participants initiating with anosmia, and total or near total recovery after 60 days. SARS-CoV-2 viral load and co-infections with other respiratory viruses were not associated with poorer olfactory outcomes.
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COVID-19 , Coinfección , Trastornos del Olfato , Humanos , SARS-CoV-2 , COVID-19/complicaciones , Anosmia/complicaciones , Anosmia/epidemiología , Estudios Prospectivos , Pandemias , Coinfección/complicaciones , Coinfección/epidemiología , Trastornos del Olfato/diagnóstico , Trastornos del Olfato/epidemiología , Trastornos del Olfato/etiología , OlfatoRESUMEN
ß2 glycoprotein I (ß2GPI) is a phospholipid binding protein that plays an important role in endothelial stability, blood coagulation, clearance of apoptotic debris and other physiologic processes. Anti-ß2GPI antibodies occur in normal individuals and transiently during the course of infections, but are also associated with thrombotic events in autoimmune disease: the antiphospholipid syndrome (APS). A total of 31 out of 37 treated leprosy patients previously found to present high titers of IgM anti-ß2GPI and/or anticardiolipin antibodies (aCL) remained positive for IgM antiphospholipid antibodies (aPL), and exhibited high titers of anti-ß2GPI. The 37 patients were part of the 77 aPL-positive patients from a previous study that evaluated 158 leprosy patients. The median time elapsed between the first and second sample was 66 months. None of the 37 patients had any thrombotic event and 24 had a reactional state and were still requiring the use of prednisone, thalidomide or both. None of them fulfilled World Health Organization criteria for leprosy recurrence.
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Autoanticuerpos/sangre , Lepra/inmunología , beta 2 Glicoproteína I/inmunología , Adulto , Anticuerpos Anticardiolipina/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Physical exercise increases serum glucocorticoids, which is believed to be involved in the fall of T3 after high intensity exercise. The objective was to evaluate whether a physical exercise session alters the thyroid economy and adrenal axis in humans, and the possible role of corticosteroids in thyroid function disturbance. Active but not athlete subjects were enrolled in an open field competition and cortisol, TSH, T3, and T4 were measured before and after the race. To give new insights into the mechanisms underlying the changes in thyroid economy after exercise, we used a rat model to evaluate the impact of blocking corticosterone synthesis during treadmill exercise by metyrapone administration. Cortisol levels increased 1.5-fold (from 28.2±3.8 to 42.2±2.2 µg/dl; p<0.05), while serum T3 decreased by 13% (from 115±5 to 99±5 µg/dl; p<0.05) 6 h after the race in humans. Also, in rats, glucocorticoid increased by 2-fold while T3 decreased 15% after exercise session (p<0.05). However, the complete blockage of corticosterone peak did not impair serum T3 decrease observed in rats submitted to exercise. Interestingly, the lack of corticosterone peak led not only to lower serum T3, but also to decreased serum T4, indicating that corticosterone might be fundamental for the maintenance of serum thyroid hormone levels after high intensity exercise. Although cortisol increases and T3 decreases after high intensity exercise in both humans and rats, it does not seem to be a cause-effect response since pharmacological blockage of corticosterone peak does not modulate T3 response.
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Ejercicio Físico/fisiología , Glucocorticoides/metabolismo , Condicionamiento Físico Animal , Triyodotironina/sangre , Adulto , Animales , Humanos , Hidrocortisona/sangre , Yoduro Peroxidasa/metabolismo , Masculino , Ratas , Tiroxina/sangre , Adulto JovenRESUMEN
AIM: This study aimed to evaluate the combined effects of exercise and antagonists of the angiotensin II and aldosterone receptors on cardiac autonomic regulation and ventricular repolarization in rats chronically treated with nandrolone decanoate (ND), a synthetic androgen. METHODS: Thirty male Wistar rats were divided into six groups: sedentary, trained, ND-treated, trained and ND-treated, trained and treated with both ND and spironolactone, and trained and treated with both ND and losartan. ND (10 mg kg(-1) weekly) and the antagonists (20 mg kg(-1) daily) of the angiotensin II AT1 (losartan) and aldosterone (spironolactone) receptors were administered for 8 weeks. Exercise training was performed using a treadmill five times each week for 8 weeks. Following this 8-week training and treatment period, electrocardiogram recordings were obtained to determine the time and frequency domains of heart rate variability (HRV) and corrected QT interval (QTc). RESULTS: Nandrolone decanoate treatment increased the QTc interval and reduced the parasympathetic indexes of HRV (RMSSD, pNN5 and high-frequency power) in sedentary and trained rats. The ratio between low- and high-frequency power (LF/HF) was higher in ND-treated groups. Both losartan and spironolactone treatments prevented the effects of ND on the QTc interval and the HRV parameters (RMSSD, pNN5, high-frequency power, and the LF/HF ratio). CONCLUSION: Our results show that chronic treatment with a high dose of ND induces cardiac parasympathetic dysfunction and disturbances in ventricular repolarization in both sedentary and exercised rats. Furthermore, inhibiting the renin-angiotensin-aldosterone system using losartan, or spironolactone, prevented these deleterious effects.
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Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Cardiopatías/inducido químicamente , Antagonistas de Receptores de Mineralocorticoides/farmacología , Nandrolona/análogos & derivados , Receptor de Angiotensina Tipo 1/metabolismo , Receptores de Mineralocorticoides/metabolismo , Anabolizantes/administración & dosificación , Anabolizantes/efectos adversos , Animales , Losartán/administración & dosificación , Losartán/efectos adversos , Masculino , Nandrolona/administración & dosificación , Nandrolona/efectos adversos , Nandrolona Decanoato , Distribución Aleatoria , Ratas , Ratas Wistar , Espironolactona/administración & dosificación , Espironolactona/efectos adversosRESUMEN
Freshwater sponges are abundant in the Amazon region and they have been known to cause dermatitis (acute inflammation) since the beginning of the 20th century. To determine whether additional constituents, besides their body spicules, cause dermatological reactions in humans, an experimental study was developed and carried out using mice and Drulia uruguayensis prepared in three different forms: intact sponges (IS), macerated sponges (MS) or isolated spicules - megascleres (ISM). The cells most commonly involved in inflammatory reactions (mast cells, eosinophils and neutrophils), as well as intraepithelial lymphocytes and degranulated mast cells, were counted so that they could be used as parameters to determine which of the sponge preparations induced the greatest reaction. The effects of the sponge on the skin were then determined by histological analysis. The results obtained showed that IS caused the greatest inflammatory reaction (p = 0.000005), activating mainly mast cells (p = 0.0018). The histopathological analysis revealed a slight loss of continuity of the epidermis when ISM or IS were applied. These findings allow us to conclude that a structurally intact sponge can cause a greater inflammatory reaction in the first contact because of its ability to perforate the skin and allow inflammatory agents to enter. Other proteins present in dried sponge bodies could induce allergic but not toxic responses (in contact with the entire sponge, a large number of pharmacologically inert proteins may be introduced, with a potential allergen).(AU)
Asunto(s)
Animales , Femenino , Adulto , Ratas , Poríferos/patogenicidad , Dermatitis por Contacto/etiologíaRESUMEN
Freshwater sponges are abundant in the Amazon region and they have been known to cause dermatitis (acute inflammation) since the beginning of the 20th century. To determine whether additional constituents, besides their body spicules, cause dermatological reactions in humans, an experimental study was developed and carried out using mice and Drulia uruguayensis prepared in three different forms: intact sponges (IS), macerated sponges (MS) or isolated spicules - megascleres (ISM). The cells most commonly involved in inflammatory reactions (mast cells, eosinophils and neutrophils), as well as intraepithelial lymphocytes and degranulated mast cells, were counted so that they could be used as parameters to determine which of the sponge preparations induced the greatest reaction. The effects of the sponge on the skin were then determined by histological analysis. The results obtained showed that IS caused the greatest inflammatory reaction (p = 0.000005), activating mainly mast cells (p = 0.0018). The histopathological analysis revealed a slight loss of continuity of the epidermis when ISM or IS were applied. These findings allow us to conclude that a structurally intact sponge can cause a greater inflammatory reaction in the first contact because of its ability to perforate the skin and allow inflammatory agents to enter. Other proteins present in dried sponge bodies could induce allergic but not toxic responses (in contact with the entire sponge, a large number of pharmacologically inert proteins may be introduced, with a potential allergen).
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Animales , Femenino , Badiaga/efectos adversos , Badiaga/toxicidad , Dermatitis , Ecosistema Amazónico , RatonesRESUMEN
Perinatal nutrition has persistent influences on neural development and cognition. In humans and other animals, protein malnutrition during the perinatal period causes permanent changes, inducing to adulthood metabolic syndrome. Feeding is mainly modulated by neural and hormonal inputs to the hypothalamus. Hypothalamic glycogen stores are a source of glucose in high energetic demands, as during development of neural circuits. As some hypothalamic circuits are formed during lactation, we studied the effects of malnutrition, during the first 10 days of lactation, on glycogen stores in hypothalamic nuclei involved in the control of energy metabolism. Female pregnant rats were fed ad libitum with a normal protein diet (22% protein). After delivery, each dam was kept with 6 male pups. During the first 10 days of lactation, dams from the experimental group received a protein-free diet and the control group a normoprotein diet. By post-natal day 10 (P10), glycogen stores were very high in the arcuate nucleus and median eminence of control group. Glycogen stores decreased during development. In P20 control animals, glycogen stores were lower when compared to P10 control animals. Animals submitted to malnutrition presented a staining even lower than control ones. After P45, it was difficult to determine differences between control and diet groups because glycogen stores were reduced. We also showed that tanycytes were the cells presenting glycogen stores. Our data reinforce the concept that maternal nutritional state during lactation may be critical for neurodevelopment since it resulted in a low hypothalamic glycogen store, which may be critical for establishment of neuronal circuitry.
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Animales Lactantes/metabolismo , Glucógeno/metabolismo , Hipotálamo/patología , Deficiencia de Proteína/patología , Envejecimiento/metabolismo , Animales , Animales Lactantes/crecimiento & desarrollo , Núcleo Arqueado del Hipotálamo/crecimiento & desarrollo , Núcleo Arqueado del Hipotálamo/metabolismo , Núcleo Arqueado del Hipotálamo/patología , Dieta con Restricción de Proteínas , Femenino , Proteína Ácida Fibrilar de la Glía , Transportador de Glucosa de Tipo 2/metabolismo , Hipotálamo/crecimiento & desarrollo , Hipotálamo/metabolismo , Masculino , Fenómenos Fisiologicos Nutricionales Maternos , Eminencia Media/crecimiento & desarrollo , Eminencia Media/metabolismo , Eminencia Media/patología , Proteína Básica de Mielina/metabolismo , Neuroglía/clasificación , Neuroglía/patología , Especificidad de Órganos , Deficiencia de Proteína/metabolismo , Distribución Aleatoria , Ratas , Ratas Wistar , Factores de Transcripción/metabolismo , Vimentina/metabolismoRESUMEN
BACKGROUND AND OBJECTIVE: Intermittent administration of the parathyroid hormone (1-34) has an anabolic effect on bone and it has been shown to reduce alveolar bone loss in experimental periodontitis models. The aim of the present study was to investigate the effect of parathyroid hormone on tissue degradation-related factors in an experimental periodontitis model in rats. MATERIAL AND METHODS: Periodontitis was induced in seventy-six male Wistar rats using ligature around the lower right first molars. The animals were then treated with parathyroid hormone (1-34) (T-group) or vehicle (C-group), three times a week for 15 d (C15, T15) or 30 d (C30, T30). At each experimental time-point, the 19 rats were killed in each group and the gingival tissue around the first lower molar was removed and prepared for the following analyses: mRNA expression of interleukin-1 beta, interleukin-6, matrix metalloproteinase (MMP)-2 and MMP-9, and gelatinolytic activity of MMP-2 and MMP-9. Hemimandibles were decalcified, and serial sections were processed and analyzed for interleukin-6 immohistochemistry. Samples were also histochemically stained by tartrate-resistant acid phosphatase (TRAP) to evaluate the number of osteoclasts present. RESULTS: Parathyroid hormone-treated samples showed decreased of levels of mRNA for interleukin-6 in the T30 group (p < 0.01) and of MMP-2 in the T15 and T30 groups (p < 0.05). Zymography assays demonstrated that treatment with parathyroid hormone led to a decrease in MMP-9 activity (p < 0.01). TRAP staining of alveolar bone revealed that osteoclasts were present in higher numbers (p < 0.05) in the groups not treated with parathyroid hormone. CONCLUSION: These data suggest that intermittent administration of parathyroid hormone can down-regulate the expression of biomarkers responsible for connective tissue breakdown and bone resorption, and potentially affect alveolar bone resorption activity.
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Interleucina-6/análisis , Metaloproteinasa 2 de la Matriz/efectos de los fármacos , Metaloproteinasa 9 de la Matriz/efectos de los fármacos , Hormona Paratiroidea/uso terapéutico , Periodontitis/prevención & control , Fosfatasa Ácida/análisis , Pérdida de Hueso Alveolar/patología , Pérdida de Hueso Alveolar/prevención & control , Proceso Alveolar/patología , Animales , Biomarcadores/análisis , Recuento de Células , Tejido Conectivo/efectos de los fármacos , Tejido Conectivo/patología , Modelos Animales de Enfermedad , Regulación hacia Abajo , Encía/efectos de los fármacos , Encía/patología , Inyecciones Subcutáneas , Interleucina-1beta/análisis , Interleucina-1beta/efectos de los fármacos , Isoenzimas/análisis , Masculino , Metaloproteinasa 2 de la Matriz/análisis , Metaloproteinasa 9 de la Matriz/análisis , Osteoclastos/patología , Hormona Paratiroidea/administración & dosificación , Periodontitis/patología , ARN Mensajero/análisis , ARN Mensajero/efectos de los fármacos , Ratas , Ratas Wistar , Fosfatasa Ácida Tartratorresistente , Factores de TiempoRESUMEN
OBJECTIVE: To identify differences in orbital flow behavior in mild and severe pre-eclamptic women compared with healthy pregnant women, demonstrated by ophthalmic artery Doppler indexes. METHODS: Ophthalmic artery Doppler indexes of 20 mild and 20 severe pre-eclamptic women were compared with 51 healthy pregnant women. Right and left eye Doppler index means were evaluated and the resistance index (RI), pulsatility index (PI), peak systolic velocity (PSV), end diastolic velocity (EDV), and peak ratio (PR) were calculated. RESULTS: Statistically significant differences were observed between PR, PSV, and EDV (P=0.0009, P=0.0020, P=0.0001) ophthalmic artery Doppler in a comparison of women with mild and severe pre-eclampsia. Statistically significant differences were seen between all Doppler indexes of the study group and healthy pregnant women. Ophthalmic PR, PSV, and EDV were significantly higher in severe pre-eclamptic cases but other index parameters did not show any difference. An elevation of diastolic and systolic flow occurred when pre-eclampsia became severe. CONCLUSION: Orbital vascular impedance reduction with orbital hyperperfusion was present in severe pre-eclamptic women compared with mild pre-eclamptic and healthy pregnant women. Ophthalmic Doppler is a novel parameter that may be useful in the diagnosis of severe pre-eclampsia.
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Flujometría por Láser-Doppler , Arteria Oftálmica/fisiología , Preeclampsia/fisiopatología , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Órbita/irrigación sanguínea , Preeclampsia/diagnóstico , Embarazo , Flujo Sanguíneo Regional , Índice de Severidad de la EnfermedadRESUMEN
Carbon nitride nanostructures have been produced by the arc-discharge technique and analyzed by mass spectrometry. A series of structured peaks in the region of masses from 480 up to 600 suggests the existence of heterofullerenes C(n-x)Nx(40 < or = n < or = 50). The structure and stability of these small fullerenes were theoretically investigated by quantum chemical calculations. The obtained heats of formation indicate that C(n) molecules stabilize upon nitrogen substitution. Two C(n-x)Nx cages are quite stable, with heats of formation per atom approaching that of C60. These molecules could be the seeds of onion-like structures seen in CN materials [Phys. Rev. Lett. 87, 225503 (2001)]].
RESUMEN
Heparin, in some regions of Brazil has been used in the treatment of bothropic accidents, but the data found in the literature are inconclusive about its effectiveness. The venoms of Bothrops atrox and of B. erythromelas were characterized according to their biological activities. The capacity of heparin in neutralizing these activities was tested with doses of 3 and 6 IU in isolated form and associated to Antibothropic Serum (ABS). It was verified that heparin, in doses of 3 and 6 IU, was not effective in neutralizing the desfibrinating and edema-forming activities of B. atrox venom and the hemorrhagic and coagulant actions of both venoms. Heparin diminished the effectiveness of the ABS in the neutralization of the hemorrhagic and edema-forming activities of the B. atrox venom. However, heparin in the 6 IU dose was capable of neutralize the edema-forming of the B. erythromelas and increase the effectiveness of the ABS. Heparin also neutralized the phospholipasic A2 activity of B. atrox (14.3%) and B. erythromelas (28.0%) venoms. For B. erythromelas venom, the associated treatment, heparin and ABS, was more effective in the neutralization of its lethal activity.
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Anticoagulantes/farmacología , Antivenenos/farmacología , Bothrops/inmunología , Venenos de Crotálidos/antagonistas & inhibidores , Heparina/farmacología , Mordeduras de Serpientes/inmunología , Animales , Antivenenos/inmunología , Coagulación Sanguínea/efectos de los fármacos , Venenos de Crotálidos/inmunología , Venenos de Crotálidos/envenenamiento , Femenino , Ratones , Pruebas de Neutralización , Fosfolipasas A/antagonistas & inhibidores , Mordeduras de Serpientes/sangreRESUMEN
The biotransformation of isosteviol (ent-16-ketobeyeran-19-oic acid) by three fungi is described. Aspergillus niger produced the 7 beta-OH derivative, ent-7 alpha-hydroxy-16-ketobeyeran-19-oic, and the 1 alpha, 7 beta-diOH derivative, ent-1 beta, 7 alpha-dihydroxy-16-ketobeyeran-19-oic acid. The 17-OH compound, ent-17-hydroxy-16-ketobeyeran-19-oic acid, was obtained with Penicillium chrysogenum. Rhizopus arrhizus produced the 7 beta-OH derivative, ent-7 alpha-hydroxy-16-ketobeyeran-19-oic acid. The isolated metabolites were characterised by IR, NMR and MS.
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Aspergillus niger/metabolismo , Diterpenos de Tipo Kaurano , Diterpenos/farmacocinética , Penicillium chrysogenum/metabolismo , Rhizopus/metabolismo , Biotransformación , Diterpenos/química , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Estructura Molecular , Espectrofotometría InfrarrojaRESUMEN
In the State of Amazonas, accidents with snakes are a public health problem. For this reasons, the objective of this work was to carry out a descriptive study of the snake accidents attended in the health units of 34 municipalities, one district and two border platoons in the State of Amazonas. The characteristics most commonly observed among those involved in snake accidents were: farmers (50. 4%), male (81.3%), belonging to the working age-group (72.1%), bitten on an upper limb (88.5%) by a "jararaca" (48.6%) or a "surucucu" (46.8%) in the rural part of the municipality (70.2%). The local signs and symptoms most frequently observed in those who received medical care more than 6 hours after the accident (57.3%) were edema (76.9%), pain (68.7%), erithema (10.2%) and hemorrhage (9. 3%). The systemic manifestation most frequently observed was hemorrhage (18.8%). Serotherapy was administered in only 65.9% of patients, the intravenous route being the route most commonly used to administer the antivenin (52.3%), while other non- recommended routes were widely used. In the majority of patients the antivenin given was antibotropic. The most frequent complications were: abscess 13.7%, necrosis 12.3%, secondary infection 8.3%, renal insufficiency 2.5% and gangrene 2.5%. The medical procedures most used in the treatment of these complications were drainage 52.6%, debridement 28.9%, amputation 10.5%, surgical cleaning 5.3% and peritoneal dialysis 2.6%. The fatality rate was 1%.
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Mordeduras de Serpientes/epidemiología , Mordeduras de Serpientes/terapia , Adolescente , Adulto , Brasil , Femenino , Humanos , Masculino , Persona de Mediana EdadAsunto(s)
Complicaciones Parasitarias del Embarazo/parasitología , Salud Urbana , Adolescente , Adulto , Brasil/epidemiología , Femenino , Hospitales Universitarios , Humanos , Embarazo , Complicaciones Parasitarias del Embarazo/diagnóstico , Complicaciones Parasitarias del Embarazo/epidemiología , Estudios RetrospectivosRESUMEN
The venoms of seven species of scorpions living in different regions of Brazil were analysed with regard to their lethality, antigenic cross-reactivity and ability to induce antibody production. In mice, the tested scorpion venoms can be grouped as: (a) highly toxic: Tityus stigmurus Thorell (LD50 = 0.773 mg/kg), Tityus bahiensis (Perty) (LD50 = 1.062 mg/kg), Tityus serrulatus Lutz and Mello (LD50 = 1.160 mg/kg), and Tityus costatus (Karsch) (LD50 = 1.590 mg/kg); (b) moderately toxic: Tityus cambridgei Pocock (LD50 = 12.136 mg/kg); and (c) practically nontoxic: Rhopalurus agamemnon (Koch) (LD50 = 36.363 mg/kg), and Brotheas amazonicus Lourenço (LD50 = 90.909 mg/kg). On electrophoresis the venoms showed many protein bands displayed along the chromatogram, most of them cross-reacting in immunoelectrophoresis and immunoblotting using horse anti-T. serrulatus, anti-T. bahiensis or anti-T. serrulatus+T. bahiensis sera as probes. The antibodies present in these antivenoms combine with venom components as measured in vitro by the ELISA assay, and neutralize their lethal effects in vivo. These results indicate that horse anti-venoms against a mixture of T. serrulatus and T. bahiensis venoms or only against T. serrulatus venom yield an antibody population able to neutralize the toxic effects found in all venoms studied.
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Antígenos/inmunología , Venenos de Escorpión/inmunología , Animales , Formación de Anticuerpos/inmunología , Western Blotting , Brasil , Reacciones Cruzadas , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Cobayas , Caballos , Sueros Inmunes/inmunología , Inmunoelectroforesis , Técnicas In Vitro , Inyecciones Intraperitoneales , Ratones , Proteínas/análisis , Venenos de Escorpión/administración & dosificación , Venenos de Escorpión/química , Venenos de Escorpión/toxicidad , EscorpionesRESUMEN
The venoms of seven species of scorpions living in different regions of Brazil were analysed with regard to their lethality, antigenic cross-reactivity and ability to induce antibody production. In mice, the tested scorpion venoms can be grouped as: (a) highly toxic: Tityus stigmurus Thorell (), Tityus bahiensis (Perty) , Tityus serrulatus Lutz and Mello (, and Tityus costatus (Karsch) ; (b) moderately toxic: Tityus cambridgei Pocock ; and (c) practically nontoxic: Rhopalurus agamemnon (Koch) , and Brotheas amazonicus Lourenço . On electrophoresis the venoms showed many protein bands displayed along the chromatogram, most of them cross-reacting in immunoelectrophoresis and immunoblotting using horse anti-T. serrulatus, anti-T. bahiensis or anti-T. serrulatus + T. bahiensis sera as probes. The antibodies present in these antivenoms combine with venom components as measured in vitro by the ELISA assay, and neutralize their lethal effects in vivo. These results indicate that horse antivenoms against a mixture of T. serrulatus and T. bahiensis venoms or only against T. serrulatus venom yield an antibody population able to neutralize the toxic effects found in all venoms studied.
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Animales , Cobayas , Ratones , Antígenos/inmunología , Escorpiones , Escorpiones/inmunología , Sueros Inmunes/inmunología , Venenos de Escorpión/administración & dosificación , Venenos de Escorpión/inmunología , Venenos de Escorpión/química , Venenos de Escorpión/toxicidad , Antivenenos/química , Antivenenos/toxicidad , Brasil , Inmunoelectroforesis , Inyecciones Intraperitoneales , Proteínas/análisisRESUMEN
1. Snake venoms from the genera Micrurus (M. ibiboboca and M. spixii) and Naja (N. naja, N. melanoleuca and N. nigricollis) were analysed, using biological and immunochemical methods, to detect pro-inflammatory activities, cobra venom factor (COF), proteolytic enzymes, thrombin-like substances, haemorrhagic and oedema-producing substances. 2. The venoms of the five snake species activate the complement system (C) in normal human serum (NHS) in a dose-related fashion, at concentrations ranging from 5 micrograms to 200 micrograms ml-1 serum. Electrophoretic conversion of C3 was observed with all venoms in NHS containing normal concentrations of Ca2+ and Mg2+, but only by venoms from N. naja and N. melanoleuca when Ca2+ was chelated by adding Mg(2+)-EGTA. 3. Purified human C3 was electrophoretically converted, in the absence of other C components, by the venoms from N. naja, N. nigricollis and M. ibiboboca. However, only the venoms from N. naja and N. melanoleuca contained a 144 kDa protein revealed in Western blot with sera against COF or human C3. 4. All venoms, at minimum concentrations of 30 ng ml-1, were capable of lysing sheep red blood cells, also in a dose-related fashion, when incubated with these cells in presence of egg yolk as a source of lecithin. Although the venoms from M. spixii and N. nigricollis showed detectable thrombin-like activity, these and the other venoms were free of proteolytic activity when fibrin, gelatin and casein, were used as substrates. 5. When tested on mice skin, all five venoms were capable of inducing an increase in vascular permeability and oedema, but were devoid of haemorrhagic producing substances (haemorrhagins). 6. These data provide evidence indicating that Elapidae venoms contain various pro-inflammatory factors which may be important in the spreading of neurotoxins throughout the tissues of the prey or human victim.
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Venenos Elapídicos/farmacología , Inflamación/inducido químicamente , Animales , Permeabilidad Capilar/efectos de los fármacos , Activación de Complemento/efectos de los fármacos , Edema/inducido químicamente , Venenos Elapídicos/química , Venenos Elapídicos/enzimología , Endopeptidasas/metabolismo , Hemólisis/efectos de los fármacos , Hemorragia/inducido químicamente , Humanos , Técnicas In Vitro , Inflamación/patología , Ratones , Ovinos , Especificidad de la Especie , Trombina/análisisRESUMEN
IgG and F(ab')2 fragments were prepared from horse plasma rich in specific antibodies against Brazilian Bothrops or Crotalus venoms. Both preparations, free of gross contamination with non-immunoglobulin proteins, were able to combine in vitro with their respective antigens, forming immune complexes at antigen excess, equivalence or antibody excess, and activating the C system, through either the classical or the alternative pathways. The IgG preparation was more effective in neutralizing the lethal factors in Bothrops or Crotalus venoms, compared with the F(ab')2 fragments. In contrast, IgG and F(ab')2 anti-Bothrops venom were almost equipotent in neutralizing the haemorrhagic and defibrinating activities in the venom. The method used to purify IgG, precipitation of most non-immunoglobulin plasma proteins with caprylic acid, produced antivenoms richer in specific antibodies, with higher specific activity, recovery and yield, compared with the method commonly used to prepare antivenoms containing F(ab')2.
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Antivenenos/inmunología , Bothrops/inmunología , Venenos de Crotálidos/inmunología , Fragmentos Fab de Inmunoglobulinas/inmunología , Inmunoglobulina G/inmunología , Animales , Complejo Antígeno-Anticuerpo , Activación de Complemento/inmunología , Venenos de Crotálidos/toxicidad , Caballos/inmunología , Ratones , Pruebas de NeutralizaciónRESUMEN
Venoms from five species of Micrurus (coral snakes) from Brazil (Amazonas State) were tested for the following effects: edematogenic, myotoxic, coagulant, hemorrhagic and phospholipase A2 (PLA2) detection. None of the venoms tested presented coagulant activity. The presence of PLA2 was detected by ELISA in the venoms of M. spixii, M. averyi and M. lemniscatus. The myotoxicity was estimated by the increase in the serum creatine kinase level and by histological analysis. All venoms, except that from M. surinamensis, induced intense edematogenic and myotoxic effects. The venom of M. averyi showed hemorrhagic activity which was confirmed by histopathological analysis. This is the first evidence of such an effect by coral snake venom.
Asunto(s)
Venenos Elapídicos/toxicidad , Elapidae , Músculos/efectos de los fármacos , Músculos/patología , Animales , Creatina Quinasa/sangre , Edema/inducido químicamente , Venenos Elapídicos/análisis , Ensayo de Inmunoadsorción Enzimática , Hemorragia/inducido químicamente , Inyecciones Intramusculares , Ratones , Fosfolipasas A/análisis , Fosfolipasas A2 , Especificidad de la EspecieRESUMEN
In the State of Amazonas and in areas nearby Manaus, the snakes responsible for the majority of accidents are Bothrops atrox and Lachesis muta muta, with a percentage of confirmed species of 76% and 17%, respectively. Frequently, in the absence of the laquetic and bothropic-laquetic antivenoms, the Instituto de Medicina Tropical de Manaus (IMTM) has been using bothropic antivenom in the treatment of laquetic accident. In this paper is related a case of accident caused by L. muta muta; the patient was treated with bothropic antivenom, and after received twenty ampoules of this antivenom, maintained blood incoagulability until the 13th day after the accident. Experiments to obtain the potency of the bothropic antivenom for the coagulant and hemorrhagic activities has been done, using Bothrops atrox venom as control. The results showed that the potency of the antivenom for the hemorrhagic activity was similar, and the potency for the coagulant activity for the L. m. muta venom was 9.2 times minor than that for B. atrox. The antibodies titles from three different lots of bothropic antivenom varied for the L. m. muta venom, and were constant for the B. atrox venom. Due to the inefficiency of the bothropic antivenom on the neutralization of the coagulant activity for the L. m. muta venom, the use of bothropic antivenom is not recommended in the treatment of Lachesis muta muta accidents.