Evaluation of cytochrome P450 activity in field populations of Cydia pomonella (Lepidoptera: Tortricidae) resistant to azinphosmethyl, acetamiprid, and thiacloprid.

The Río Negro and Neuquén Valley is the most important apple and pear growing region in Argentina. Cydia pomonella L. (Lepidoptera: Tortricidae), the main fruit-tree pest is being controlled by azinphosmethyl (AzMe), acetamiprid (Acet), and thiacloprid (Thia) among other insecticides. The objective of this study was to evaluate the response of neonate larvae of codling moth to these three insecticides and on the role of cytochrome P450 monooxygenase in their toxicity. All field populations presented significantly lower mortality to a discriminating concentration (DC) of Acet and AzMe. In addition, 13 of the 14 populations showed significantly lower mortality to DC of Thia. Most of the field populations (71%) showed significantly higher 7-ethoxycoumarine O-deethylase activity compared with the laboratory-susceptible strain. While positive significant correlation (gamma = 0.59) was found between Thia and AzMe mortalities at the DC level, no significant correlations were detected between Acet and Thia (gamma = 0.35) or Acet and AzMe (gamma = 0.12). However, Acet and Thia mortalities were significantly correlated to the percentage of individuals exhibiting 7-ethoxy-coumarine O-deethylase activity activities higher than the mean upper 95% confidence limit of the susceptible strain (gamma = -0.52 and gamma = -0.63, respectively).

[Kidney revascularization and function recovery in patients in dialysis]. / Revascularización renal y recuperación de la función en pacientes en diálisis.

The available literature was reviewed to analyze the indications and results of the surgical restoration of flow to ischemic kidneys in dialyzed patients with ischemic nephropathy. Only 57 were found, a small number compared with the estimated percentage (5 to 15%) of ischemic insufficiency in dialyzed patients. Atherosclerosis was the main cause of ischemia and most patients were over the seventh decade of life. Common clinical findings were uncontrolled hypertension and/or acute cardiac failure, symptomatic atherosclerotic disease in other areas and rapid deterioration of renal function. Kidneys recovered after variable periods of ischemia (days to 13 months of dialysis, mean 30.5 days), with small size, 9, 8 or even 7 cm, absent nephrograms of flat flow curves in isotopic studies or without distal arteries and/or collaterals in the angiogram. Total arterial occlusion was more frequent than stenosis. After surgery the patients recovered immediately (35%) or required transitory dialysis (52%); in a few (12.2%) function was not restored. Hypertension improved or was cured in almost all patients. The good results persisted during long periods. A better knowledge of the disease, early detection and treatment, will improve the quality of life and survival of patients with ischemic nephropathy.

Relationship between the development of diaphragma sellae and the morphology of the sella turcica and its content.

The impaired formation of the diaphragma sellae may lead to the development of the empty-sella syndrome. This structure, when fully formed, is a protective barrier against the pulsating action that the cerebrospinal fluid exerts on the sellar content. There are anatomical features which support this belief, but they also suggest that the development of the diaphragma sellae is a factor which determines the morphology of the sella turcica and its contents. Those human specimens which do not have diaphragma sellae or in which it is only partially developed, are characterized by a smaller hypophysis, always located at the inferior and/or posterior half of the sella, with a larger sellar volume and frequently greater fragility of its bony walls. These findings, although rare (5% of the cases), are indirect signs of the important role which the diaphragma sellae plays in the sellar region.