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1.
World Dev ; 121: 163-177, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31481824

RESUMEN

Over the last few decades rapid advances in processes to collect, monitor, disclose, and disseminate information have contributed towards the development of entirely new modes of sustainability governance for global commodity supply chains. However, there has been very little critical appraisal of the contribution made by different transparency initiatives to sustainability and the ways in which they can (and cannot) influence new governance arrangements. Here we seek to strengthen the theoretical underpinning of research and action on supply chain transparency by addressing four questions: (1) What is meant by supply chain transparency? (2) What is the relevance of supply chain transparency to supply chain sustainability governance? (3) What is the current status of supply chain transparency, and what are the strengths and weaknesses of existing initiatives? and (4) What propositions can be advanced for how transparency can have a positive transformative effect on the governance interventions that seek to strengthen sustainability outcomes? We use examples from agricultural supply chains and the zero-deforestation agenda as a focus of our analysis but draw insights that are relevant to the transparency and sustainability of supply chains in general. We propose a typology to distinguish among types of supply chain information that are needed to support improvements in sustainability governance, and illustrate a number of major shortfalls and systematic biases in existing information systems. We also propose a set of ten propositions that, taken together, serve to expose some of the potential pitfalls and undesirable outcomes that may result from (inevitably) limited or poorly designed transparency systems, whilst offering guidance on some of the ways in which greater transparency can make a more effective, lasting and positive contribution to sustainability.

2.
Discov Oncol ; 14(1): 178, 2023 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-37740836

RESUMEN

INTRODUCTION: Synergistic effects have been discussed for tyrosine kinase (TKI) and immune checkpoint inhibitors (ICI). Primary resistance to TKI might disturb subsequent ICI effectiveness. The objective was to investigate, if primary resistance to 1st line TKI monotherapy predicts response to ICI in subsequent therapy lines and impacts overall survival (OS) in advanced renal cell carcinoma (aRCC). MATERIALS AND METHODS: Retrospectively, aRCC patients which received front-line TKI from 2016 to 2019 were analyzed for the outcomes primary resistance (1LR), response to sequential ICI therapy, progression free survival (PFS) and overall survival (OS). Kaplan-Meier-estimates, Cox proportional hazards and logistic regression were used. RESULTS: Primary resistance to front-line TKI was observed in 27 (53%) of 51 patients. Groups with disease control (DC) and 1st line TKI resistance (1LR) were not different at baseline with regard to clinicopathological features. Median duration on 1st line therapy was significantly shorter in the 1LR (5.1 months) than in the DC (14.7 months) group (p = 0.01). Sequential therapy was started in 21 (75%) and 12 (52%) patients of 1LR and DC groups using nivolumab in 16 (76%) vs. 11 (92%) cases (p > 0.05). Logistic regression revealed that 1LR status, neutrophil-to-lymphocyte ratio < 3, IMDC favorable prognosis and clear cell histology had no significant impact on responsiveness to ICI in subsequent therapy lines. Cox proportional hazards demonstrated no significant association of 1LR status with PFS and OS in patients who received subsequent ICI treatment. CONCLUSION: Primary TKI resistance of aRCC was neither significantly associated with responsiveness to ICI during sequential therapy nor with PFS and OS. This adds the evidence for ICI based sequential therapy in primary TKI resistant aRCC.

3.
Arch Surg ; 115(7): 874-7, 1980 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6770793

RESUMEN

The perforation rate of the cat esophagus varies as the log of the pepsin concentration when the esophagus is perfused in vivo with canine gastric juice at constant acidity, temperature, and pressure. The esophagus is extremely sensitive to gastric juice, frequently perforating before 60 minutes of perfusion. The maximal response is achieved with pepsin concentrations of 0.3 mg/mL, although the canine stomach is capable of concentrations as high as 1.3 mg/mL after vagal stimulation with 2 deoxy-D-glucose. These findings emphasize that peptic activity contributes significantly to initial acute esophageal ulceration induced by gastric secretions.


Asunto(s)
Perforación del Esófago/fisiopatología , Pepsina A/farmacología , Úlcera Péptica Perforada/fisiopatología , Animales , Gatos , Perros , Perforación del Esófago/etiología , Esófago/efectos de los fármacos , Concentración de Iones de Hidrógeno , Pepsina A/análisis , Úlcera Péptica Perforada/etiología , Perfusión , Presión , Temperatura
4.
Arch Surg ; 112(2): 193-7, 1977 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-319775

RESUMEN

This controlled study shows that the rabbit is more vulnerable to erosive gastritis after stress of operation, weight loss, and hypersecretion or acute ischemia than is the cat. Rabbit gastric juice also produces more erosions in the Shay rat preparation after four hours than does cat gastric juice (P less than .05). In vitro, rabbit pepsin has 1.5 times greater specific activity and possesses other kinetic differences. The deleterious effect of these qualitative differences on gastric mucosa may also be augmented by quantitative differences. Hypersecretion of pepsin has been reported once the mucosa is damaged. We conclude that demonstration of species-related differences in pepsin activity helps to explain an apparent discrepancy noted by others--namely, why the rabbit is so much more susceptible to stress-produced erosions than the cat or other experimental animals.


Asunto(s)
Gastritis/fisiopatología , Pepsina A/fisiología , Animales , Gatos , Jugo Gástrico/metabolismo , Mucosa Gástrica/patología , Gastritis/etiología , Cinética , Pepsina A/análisis , Conejos , Ratas , Especificidad de la Especie , Úlcera Gástrica/etiología , Úlcera Gástrica/patología , Úlcera Gástrica/fisiopatología , Estrés Fisiológico/complicaciones
5.
Pancreas ; 4(4): 423-8, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2474812

RESUMEN

There are two tissue-fixed cholinesterases in dog pancreas: acetylcholinesterase and butyrylcholinesterase. In the present experiments, an organophosphate that only inhibits butyrylcholinesterase (isopropylpyrophosphoramide, or iso-OMPA) was compared with echothiophate and a nonorganophosphate compound, physostigmine. The latter two agents inhibit both cholinesterases. Fresh canine pancreas from anesthetized dogs was minced into fragments and suspended in Eagle's solution gassed with 100% O2. Amylase release was measured by the Phadebas method. In 2-h dose-response studies, there was a fivefold increase in sensitivity to acetylcholine when fragments were preincubated 1 h with iso-OMPA. There was a 1,000-fold increase in sensitivity when fragments were preincubated for 1 h in echothiophate. Basal amylase release in incubates with echothiophate were also increased. In dose-response studies with CCK-8, iso-OMPA was without effect, but echothiophate treatment resulted in a greater total response to CCK-8. There was a corresponding increase in basal output with echothiophate alone. Physostigmine also potentiates the response to CCK-8. Cumulative responses up to 3 h with half-maximal acetylcholine or half-maximal CCK-8 doses showed enhanced total output in fragments preincubated with echothiophate (p less than 0.05). The enhancement effect was atropine-sensitive to hexamethonium ganglionic blockade. In calcium-free medium, the enhancement with echothiophate was greatly reduced but still present. Inhibitors of both cholinesterases in the pancreas cause a greater total amylase release to sub-maximal doses of acetylcholine and CCK-8 than agents that only inhibit butyrylcholinesterase. Though our data do not provide direct proof, the results could be explained by a greater accumulation of endogenous acetylcholine when both cholinesterases are inhibited.


Asunto(s)
Acetilcolinesterasa/metabolismo , Amilasas/metabolismo , Butirilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/farmacología , Colinesterasas/metabolismo , Yoduro de Ecotiofato/farmacología , Compuestos Organofosforados/farmacología , Páncreas/enzimología , Fisostigmina/farmacología , Tetraisopropilpirofosfamida/farmacología , Amilasas/antagonistas & inhibidores , Animales , Colecistoquinina/farmacología , Perros , Técnicas In Vitro , Páncreas/efectos de los fármacos
6.
Pancreas ; 5(2): 177-82, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2315293

RESUMEN

Sublethal doses of organophosphate anticholinesterases cause acute pancreatitis in dogs within 2 h. In vitro studies using canine pancreatic fragments have also demonstrated that the peak of amylase release in response to acetylcholine is shifted far to the left after incubation with the organophosphates echothiophate (10(-4) M) or tetraisopropyl pyrophosphoramide (iso-OMPA) (10(-3) M), indicating an increased sensitivity of response. The present in vitro study examined whether there was also an increased susceptibility to acinar cell damage at the electron microscopic level after acetylcholine or cholecystokinin. Minced pieces of whole fresh canine pancreas 2-3 mm in size were placed in buffered Eagle's solution and gassed with 100% O2. After pretreatment 1 h with echothiophate or iso-OMPA, they were then incubated with acetylcholine (10(-5) M). Other tissues preincubated with echothiophate were stimulated with cholecystokinin (10(-9) M). These are submaximal doses for untreated canine pancreatic fragments. After acetylcholine and echothiophate or acetylcholine and iso-OMPA, there was extensive acinar damage with the appearance of large vacuoles and lakes, and interstitial edema. There was evidence of intense supramaximal stimulation and lateral exocytosis. Similar destructive changes were seen after echothiophate and cholecystokinin. In control sections from tissues stimulated with acetylcholine (10(-5) M) or cholecystokinin (10(-9) M, there were lumenal exocytotic patterns typical of submaximal stimulation. Other controls, organophosphate alone and unstimulated basal conditions, showed only minor changes. It is concluded that the increased sensitivity to acetylcholine after organophosphate incubation correlates with an increased susceptibility to acinar ultrastructural damage from acetylcholine and cholecystokinin.


Asunto(s)
Acetilcolina/toxicidad , Colecistoquinina/toxicidad , Yoduro de Ecotiofato/toxicidad , Compuestos Organofosforados/toxicidad , Pancreatitis/inducido químicamente , Tetraisopropilpirofosfamida/toxicidad , Acetilcolina/administración & dosificación , Enfermedad Aguda , Animales , Colecistoquinina/administración & dosificación , Perros , Sinergismo Farmacológico , Yoduro de Ecotiofato/administración & dosificación , Microscopía Electrónica , Pancreatitis/patología , Tetraisopropilpirofosfamida/administración & dosificación
7.
Pancreas ; 2(6): 664-8, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-2449688

RESUMEN

Organophosphates (OPs) cause irreversible inhibition of cholinesterases (ChEs) and profound cholinergic stimulation. There are major differences in the response of the dog and cat pancreas to the in vivo administration of Diazinon (O,O-diethyl O-2-isopropyl-4-methyl-6-pyrimidyl phosphothioate), a butyrylcholinesterase (BuChE) inhibitor. Acute edematous pancreatitis is found in the dog but not in the cat. The present experiments were designed to see what effect OP had in vitro on pancreatic exocrine function of dog, cat, and guinea pig, and whether the effects were consistent with an anti-ChE activity. A water-soluble OP agent, tetraisopropyl pyrophosphoramide (iso-OMPA) at 10(-3) M, which like Diazinon inhibits BuChE, was used. Minced pieces of fresh whole pancreata 3 mm in size were taken from 3 dogs, 4 guinea pigs, and 2 cats. The tissues were placed in flasks containing Eagle's solution and gassed with 100% O2. Cumulative amylase release was measured by Phadebas method up to 3 h. At half-maximal acetylcholine (ACH) concentration (10(-5) M), the canine pancreas pretreated with iso-OMPA (10(-3) M) showed a 42-87% greater release of amylase than tissues receiving ACH alone (p less than 0.001). The same potentiated response to ACH was seen in guinea pig pancreas pretreated with iso-OMPA (p less than 0.001), but iso-OMPA pretreatment did not augment the ACH response in the cat. Atropine pretreatment effectively blocked all ACH responses, and there was no effect seen with iso-OMPA alone. In the dog, iso-OMPA in combination with half-maximal carbachol (10(-6) M), or in combination with half-maximal cholecystokinin (CCK-8) stimulation (10(-9) M), provided no potentiated amylase release.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Amilasas/metabolismo , Inhibidores de la Colinesterasa/toxicidad , Diazinón/toxicidad , Insecticidas/toxicidad , Páncreas/enzimología , Acetilcolina/farmacología , Animales , Butirilcolinesterasa , Carbacol/farmacología , Gatos , Colecistoquinina/farmacología , Perros , Relación Dosis-Respuesta a Droga , Cobayas
8.
Pancreas ; 6(4): 398-403, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1715083

RESUMEN

Human pancreas contains two cholinesterase isoenzymes: acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). In the present study, binding potency of two organophosphates for human cholinesterases were compared by the Ellman method. Echothiophate was found to have much greater potency than iso-OMPA for both cholinesterases. Using Karnovsky histochemical stains on human pancreatic tissue, the same results were confirmed. Dose-response studies with acetylcholine were done on viable pancreas fragments from nine human donors, without pancreatic disease (group I). Cold-preservation time was less than 30 h. Pancreas was minced into fragments, after the technique of Scheele and Palade, placed in Eagle's medium, and gassed with O2. Amylase release was measured by the Phadebas Method and corrected for basal release. There was a dose-dependent response to acetylcholine at 1 and 2 h, with a shift in peak amylase release to the left, when fragments were preincubated in 10(-4) M echothiophate. This indicated a 100-fold increase in sensitivity to acetylcholine. In three patients with chronic pancreatitis (Group II), there were variable patterns of response of amylase release to acetylcholine, and higher basal outputs. In Group III, prolonged storage conditions of over 40 h were tested for 4 pancreas donor tissues. There was no response to acetylcholine. These studies show that for up to 30 h cold storage, fragments of pancreas from human organ donors respond to acetylcholine in dose-dependent manner. An organophosphate, echothiophate (10(-4) M) which inhibits both cholinesterases, increases pancreatic sensitivity to acetylcholine, and these results are similar to findings from canine pancreas fragments, which also showed increased sensitivity.


Asunto(s)
Acetilcolina/farmacología , Compuestos Organofosforados/farmacología , Páncreas/efectos de los fármacos , Amilasas/metabolismo , Colinesterasas/metabolismo , Relación Dosis-Respuesta a Droga , Yoduro de Ecotiofato/metabolismo , Yoduro de Ecotiofato/farmacología , Humanos , Compuestos Organofosforados/metabolismo , Páncreas/enzimología , Páncreas/metabolismo , Pancreatitis/inducido químicamente , Tetraisopropilpirofosfamida/metabolismo , Tetraisopropilpirofosfamida/farmacología
9.
Pancreas ; 8(2): 171-5, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8460092

RESUMEN

Viable pancreas fragments from five human donors were incubated in oxygenated buffered Eagle Medium. The preparation and incubation conditions were based on the method of Scheele and Palade. In Group 1 there was 1-h preincubation with echothiophate (10(-4) M); then, acetylcholine (10(-5) M) was added. After 2 h tissues were prepared for electron microscopy. Acinar injury with vacuole formation was apparent. Many of these changes were observed in fragments incubated only with acetylcholine (10(-5) M) (Group 2) and in incubates with echothiophate only (10(-4) M) (Group 3); only minor changes were seen in controls with Eagle's Medium (Group 4). Large vacuoles were significantly more numerous in Group 1 than in Control Group 4 (p < 0.05). Zymogen granules were depleted in Groups 1, 2, and 3. This depletion was significant in Group 1 when compared with Group 4 (p < 0.02). These results extend previous in vitro results that showed increased amylase release after echothiophate treatment in human pancreas and a left shift in response to acetylcholine.


Asunto(s)
Yoduro de Ecotiofato/toxicidad , Pancreatitis/inducido químicamente , Acetilcolina/toxicidad , Enfermedad Aguda , Humanos , Técnicas In Vitro , Microscopía Electrónica , Páncreas/ultraestructura , Pancreatitis/patología
10.
Am J Surg ; 147(1): 72-7, 1984 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6691555

RESUMEN

Severe epithelial hyperplasia was produced in a canine model by the perfusion of the main pancreatic duct with 15 mM of deoxycholate at rates as low as 1.5 ml/day in 6 to 14 days. At higher rates (5 ml/day) deoxycholate caused complete epithelial cell lysis in the duct closest to the tip of the cannula with hyperplastic changes downstream from this section. Perfusion with a buffer solution alone and cannulation alone produced none of these changes in similar duct segments. No hyperplasia was seen in the upstream cannula obstructed duct, even in the presence of severe atrophy. Long-term (81 days) perfusion with 3 mM of deoxycholate at 3 ml/day resulted in more severe hyperplasia that still appeared benign. When glycine-conjugated deoxycholate was perfused through the duct, hyperplasia but no cell lysis was seen. In vitro, deoxycholate caused epithelial cell lysis in pancreatic duct fragments at concentrations of 0.5 mM and above. The results of this study suggest that secondary bile salts or other similar surface-active cytotoxic agents present in the biliary tree or duodenum may play a more important role in the pathogenesis of pancreatic ductal epithelial hyperplasia associated with pancreatic cancer than ductal obstruction.


Asunto(s)
Ácido Desoxicólico/toxicidad , Conductos Pancreáticos/patología , Animales , Reflujo Biliar/complicaciones , Ácido Desoxicólico/metabolismo , Perros , Epitelio/patología , Hiperplasia , Técnicas In Vitro
11.
Artículo en Inglés | MEDLINE | ID: mdl-3598877

RESUMEN

The organophosphate insecticide Diazinon has been reported to cause acute pancreatitis in dogs. Based on histochemical examination of the acinar tissue, it was suggested that pancreatic tissue-fixed butyrylcholinesterase (BuChE) is the target enzyme of organophosphate toxicity. To further evaluate this theory, we exposed dogs, cats, and guinea pigs to a single sublethal dose of the organophosphate insecticide Diazinon (75 mg/kg). In cats, which lack pancreatic BuChE, no pathological changes occurred after two, three, and six hours, whereas in the guinea pigs as in dogs, both having abundant pancreatic BuChE, vacuolization of the acinar cells, interstitial edema and vasculitis indicate acute edematous pancreatitis as early as two hours. Atropine pretreatment (0.2 mg/kg) gave complete protection against pancreatitis. It was concluded that inhibition of pancreatic BuChe leads to cholinergic hyperstimulation of the acinar cell, which results in acute pancreatitis, and that pancreatic BuChE is essential for dogs and guinea pigs to downregulate cholinergic excitation. The insecticide pancreatitis model is considered a simple, non-invasive, reproducible, and cheap and useful method to evaluate early changes and methods of treatment in acute pancreatitis. Pancreatitis in humans has also been reported after accidental insecticide exposure.


Asunto(s)
Diazinón/toxicidad , Insecticidas/toxicidad , Páncreas/patología , Animales , Atropina/farmacología , Gatos , Perros , Cobayas , Microscopía Electrónica , Páncreas/efectos de los fármacos , Páncreas/ultraestructura , Secretina/farmacología , Especificidad de la Especie
12.
Med Klin (Munich) ; 92 Suppl 3: 17-9, 1997 Sep 15.
Artículo en Alemán | MEDLINE | ID: mdl-9417488

RESUMEN

PATIENTS AND METHOD: Substitution of selenium was performed in the University Clinic of Paediatric Surgery in Dresden in the time from 1994 to 1996 in 34 children aged 1 to 16 years with severe inflammatory surgical diseases as well a s widespread burns. Seven further patients have been examined within this time who have not received substitution of selenium as preliminary comparison group. All these patients fulfilled the criteria of "Systemic Inflammatory Response Syndrome" (SIRS). The following paraclinical parameters were examined: white cell count, interleukin 6, C-reactive protein, fibrinogen, malondialdehyde, activity of glutathione peroxidase in plasma and level of selenium in plasma and whole blood. RESULTS: Patients with initially low level of selenium who received substitution of selenium reached normal ranges more quickly than patients without substitution. Originally partly elevated values of malondialdehyde as sign of increased peroxidation of lipids were normalized under substitution of selenium. Initially low activity of selenium level in plasma showed a clear increase under substitution of selenium as sign of increased protection of the cell membrane. CONCLUSION: The substitution of selenium in children with SIRS is a supportive therapy.


Asunto(s)
Antioxidantes/administración & dosificación , Quemaduras/cirugía , Selenito de Sodio/administración & dosificación , Síndrome de Respuesta Inflamatoria Sistémica/cirugía , Adolescente , Quemaduras/enzimología , Niño , Preescolar , Femenino , Glutatión Peroxidasa/sangre , Humanos , Lactante , Peroxidación de Lípido/efectos de los fármacos , Masculino , Malondialdehído/sangre , Especies Reactivas de Oxígeno/metabolismo , Síndrome de Respuesta Inflamatoria Sistémica/enzimología
13.
Med Klin (Munich) ; 94 Suppl 3: 93-6, 1999 Oct 15.
Artículo en Alemán | MEDLINE | ID: mdl-10554541

RESUMEN

PATIENTS AND METHOD: At the Clinic for Paediatric Surgery of the University of Dresden, in a time period ranging from 5/1994 to 12/1996, all patients aged between 1 and 16 years with severe inflammatory surgical diseases or extended scalded skin, were given an adjuvant selenium substitution. As control group, all patients with the same diagnosis and age treated during the months 1/1997 to 12/1998, did not receive this adjuvant selenium substitution. All these patients fulfilled the criteria of "Systemic Inflammatory Response Syndrome" (SIRS). The selenium-therapy group consisted of 34 patients and the control group without substitution consisted of 31 patients. The following laboratory parameters were measured on the 1st, 2nd, 3rd, 6th and last treatment day: white blood cell count, interleukin 6, C-reactive protein, fibrinogen, malondialdehyde, activity of glutathione peroxidase in plasma and level of selenium in plasma and whole blood. RESULTS: The initially high interleukin 6 rates declined significantly in both groups from the 2nd day on. The acute phase proteins, i.e. the C-reactive protein and fibrinogen, normalized in both groups after the 3rd day of treatment. The initial low rates of selenium in plasma and blood gained more rapidly a normal level in the therapy group than in the control group. On the 1st day of therapy the glutathione peroxidase activity in plasma was in both groups at the inferior limit of norm range and remained at this level in the control group for the whole observation period. In the selenium-substitution group on the contrary, these initial low values raised to the double as an expression of an elevated cell membrane protection. The initial significant elevated malondialdehyde rates in both groups, expressing a raised lipidperoxidation, fell down to a normal level in the selenium-substitution group, whereas they remained at their initial high level in the control group during the whole observation period. CONCLUSION: The substitution of selenium in children with SIRS is a supportive therapy.


Asunto(s)
Selenio/administración & dosificación , Síndrome de Respuesta Inflamatoria Sistémica/tratamiento farmacológico , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Estrés Oxidativo/efectos de los fármacos , Síndrome de Respuesta Inflamatoria Sistémica/etiología , Resultado del Tratamiento
20.
Cell Tissue Res ; 325(1): 175-87, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16525830

RESUMEN

Neuronal differentiation is characterized by stereotypical sequences of membrane channel and receptor acquisition. This is regulated by the coordinated interactions of a variety of developmental mechanisms, one of which is the control by steroid hormones. We have used the metamorphosis of the holometabolous insect, Manduca sexta, as a model to study effects of 20-hydroxyecdysone on the maturation of thoracic neuron membrane channel expression. To test for direct hormone action, neurons were dissociated into primary cell culture on the first day of pupal life. In situ hybridization demonstrated that the amount of expression of the acetylcholine receptor alpha subunit, MARA1, was not affected by 20-hydroxyecdysone. Immunocytochemistry with an antibody directed against the SP19 segment of voltage-gated sodium channels revealed no effect of 20-hydroxyecdysone treatment during the first 6 days in culture. SP19 sodium channel protein was evenly distributed along all neurites. In contrast, after 8 days in culture, 20-hydroxyecdysone increased the amount of SP19 protein expression and strongly affected its distribution in differentiating neurons. In the presence of 20-hydroxyecdysone, patches of high densities of SP19 sodium channel protein were found in growth cones close to the base of filopodia. This is a further step toward unraveling the blend of membrane proteins under the control of steroids during the development of the central nervous system of postembryonic Manduca. Our results, taken together with previous studies, indicate that 20-hydroxyecdysone does not affect the expression of potassium membrane current or of the nicotinic acetylcholine receptor but instead regulates the amplitude of the calcium membrane current and the amount and distribution of SP19 sodium channel protein.


Asunto(s)
Sistema Nervioso Central/efectos de los fármacos , Ecdisterona/farmacología , Manduca/metabolismo , Neuronas/efectos de los fármacos , Canales de Sodio/efectos de los fármacos , Animales , Células Cultivadas , Sistema Nervioso Central/citología , Sistema Nervioso Central/metabolismo , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Inmunohistoquímica , Hibridación in Situ , Manduca/anatomía & histología , Manduca/crecimiento & desarrollo , Microscopía Confocal , Neuronas/citología , Neuronas/metabolismo , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Canales de Sodio/metabolismo , Tórax/citología
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