Improved systolic ventricular function with normal myocardial mechanics in compensated cardiac hypertrophy

There still controversy about the relation between changes in myocardial contractile function and global left ventricular (LV) performance during stable concentric hypertrophy. To clarify this, we analyzed LV function in vivo and myocardial mechanics in vitro in rats with pressure overload-induced cardiac hypertrophy. Male Wistar rats (70 g) underwent ascending aorta stenosis for 8 weeks (group AAS, n=9). LV performance was assessed by transthoracic echocardiography under light anesthesia. Myocardial function was studied in isolated papillary muscle preparation during isometric contraction. The data were compared with age- and sex-matched sham-operated rats (group C, n=9). LV weight-to-body weight ratio (C: 2.0 ± 0.5 mg/g; AAS: 3.3 ± 0.7 mg/g), LV relative wall thickness (C: 0.19 ± 0.02; AAS; 0.34 ± 0.10), and LV fractional shortening (C: 54 ± 5%; AAS: 70 ± 8%) were increased in the group AAS (p<0.05). Echocardiographic analysis also indicated a significant association (r=0.74; p<0.001) between percent fractional shortening and LV relative wall thickness. The performance of AAS isolated muscle revealed that active tension (C: 6.6 ± 1.7 g/mm 2; AAS: 6.5 ± 1.5 g/mm 2) and maximum rate of tension development (C: 69 ± 21 g/mm 2/s; AAS: 69 ± 18 g/mm 2) were not significantly different from group C (p>0.05). In conclusion: 1) Compensated pressure-overload myocardial hypertrophy is associated with preserved myocardial function and increased ventricular performance; 2) The improved LV function might be due to the ventricular remodeling characterized by an increased relative wall thickness. Copyright © 2002 By PJD Publications Limited.

Visceral mast cell tumor in a captive black jaguar (Panthera onca)

Little is known about neoplasia in the jaguar (Panthera onca), the largest American feline. A captive black jaguar was diagnosed at necropsy with a mastocytic form of visceral mast cell tumor similar to that which occurs in domestic cats. This animal had no previous clinical disease and died during anesthesia for a routine dental treatment.

Comparative analysis of tissue reactions to anesthetic solutions: histological analysis in subcutaneous tissue of rats.

Postanesthetic pain is a relatively common complication after local anesthesia. This complication may be caused by the anesthetic technique or by the anesthetic solution used. Tissue reactions induced by the anesthetic solutions may be one of the factors resulting in pain after anesthesia. The objective of this study was to comparatively analyze tissue reactions induced by different anesthetic solutions in the subcutaneous tissue of rats. The following solutions were utilized: 2% lidocaine without vasoconstrictor; a 0.5% bupivacaine solution with 1:200,000 adrenaline; a 4% articaine solution and 2% mepivacaine, both with 1:100,000 adrenaline; and a 0.9% sodium chloride solution as a control. Sterilized absorbent paper cones packed inside polyethylene tubes were soaked in the solutions and implanted in the subcutaneous region. The sacrifice periods were 1, 2, 5, and 10 days after surgery. The specimens were prepared and stained with hematoxylin and eosin for histological analysis. The results showed that there is a difference in tissue irritability produced by the local anesthetic solutions. The results also showed that there is no relation between the concentration of the drug and the inflammatory intensity, that the mepivacaine and articaine solutions promoted less inflammatory reaction than the bupivacaine, and that the lidocaine solution produced the least intense inflammation.

Labio doble congénito asociado a hemangiomas: A propósito de un caso

Double lip is a developmental abnormality which may occur either isolated or as a component of Ascher's syndrome. A case of congenital double lip associated to hemangiomas and enlargement of the thyroid is reported. The oral and facial hemangiomas were excised under local anesthesia. Surgical reconstruction of the upper lip was done in order to reduce the interference with speech and mastication. The recognition and treatment of the abnormalities are discussed.

Tamoxifen down-regulates CaMKII messenger RNA levels in normal human breast tissue

Tamoxifen was proven to reduce the incidence of breast cancer by 49% in women at increased risk of the disease in the Breast Cancer Prevention Trial. In order to identify potential candidates to explain the preventive effect induced by tamoxifen on breast cancer, normal breast tissue obtained from 42 fibroadenoma patients, randomly assigned to receive placebo or tamoxifen, was analyzed by the reverse Northern blot and RT-PCR techniques. The cDNA fragments used on Northern blot membranes were generated by the Human Cancer Genome Project funded by the Ludwig Institute for Cancer Research and FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo, Brazil). Total RNA was obtained from normal breast tissue from patients with clinical, cytological and ultrasound diagnosis of fibroadenoma. After a 50-day treatment with tamoxifen (10 or 20 mg/day) or placebo, normal breast tissue adjacent to the tumor was collected during lumpectomy with local anesthesia. One differentially expressed gene, Calcium/calmodulin-dependent protein kinase II (CaMKII), was found to be down-regulated during TAM treatment. CaMKII is an ubiquitous serine/threonine protein kinase that has been implicated in the diverse effects of hormones utilizing Ca2+ as a second messenger as well as in c-fos activation. These results indicate that the down-regulation of CaMKII induced by TAM might represent alternative or additional mechanisms of the action of this drug on cell cycle control and response to hormones in normal human breast tissue.

Injeção subaracnóidea inadvertida de corticoíde em tratamento de dor crônica da coluna lombar. Relato de caso

BACKGROUND AND OBJECTIVES: Before epídural steroids were used in chronic lumbar pain, subarachnoid injection of these agents was the treatment of choice. Although still preconized by some authors, this technique may lead to severe complications with neurological sequelae. This report aimed at describing a case of accidental subarachnoid injection of steroid associated to local anesthetics during epidural puncture to treat lumbar pain. CASE REPORT: Male patient, 46 years old, followed byneuro-surgery for presenting right sciatic pain for 9 month, refractory to clinical treatment due to L 4-L 5 disk protrusion confirmed by CT scan, without neurological deficit. Epidural puncture for pain treatment was performed in L 4-L 5 with 17G needle and 10 mL solution were injected containing 4 mL of 0.25% bupivacaine, 80 mg methylprednisolone and 4 mL of 0.9% saline. Although there has not been CSF reflux, 5 minutes after injection there were sensory block in T 4 and motor block in T 6, associated to blood pressure and heart rate decrease. CONCLUSIONS: Accidental subarachnoid injections with the association of steroids for pain relief may cause adverse effects. There are several risks, varying from mild transient symptoms to nervous injuries, including spinal cord injuries. Our patient had no sequelae from the accidental subarachnoid injection, probably because it has been a single injection.

Cinedacryocystography in the diagnosis of lacrimal obstruction in children

Purpose: To analyze the cinedacryocystography in children with congenital nasolacrimal obstruction suspicion. Methods: The cinedacryocystographic examination was done in 143 children (58% of girls and 42% of boys) younger than 5 years old, suspected of congenital nasolacrimal obstruction. The exams were done under general anesthesia and the children were probed immediately when obstruction was detected. Results: Epiphora, discharge or both were the most common complaints. Nevertheless 11% children had undergone unsuccessfully probing once, no one had any radiologic evaluation previously. The cinedacryocystographic exam showed nasolacrimal duct obstruction in 65,73%. Permeable lacrimal vies were presented in 34,3% of the children with epiphora. The obstruction was mainly at the Arlt's sinus. Using the cinedacryocystography, it was possible to observe the lacrimal sac enlargement and alterations in the contiguous structures such as hypertrophic turbinates (91,1%), sinusitis (44,6%) and septum deviation (24,1%). Conclusion: Cinedacryocystographic evaluation provides important information about lacrimal system obstruction in children, therefore, it is useful in all children with suspected congenital lacrimal obstruction.

Comparison of the effects of barbiturate, benzodiazepine and ketamine on visual evoked potentials in rabbits

The aim of this study was to compare the effects of barbiturate, benzodiazepine and ketamine on flash-evoked potentials (F-VEP) in adult rabbits. A total of 36 animals were studied, 16 after pentobarbital endovenous (EV) inffusion, 10 after midazolam EV administration, and 10 after ketamine EV inffusion. Pentobarbital induced triphasic F-VEP, first negative (N1), secondpositive (P1), third negative (N2) waves, all with large amplitudes and P1 with well-defined morphology. Mean P1 latency was 33ms. Midazolam induced similar but less defind triphasic waves, with mean latency of 27ms. Ketamine induced poliphasic and poorly defined F-VEP, with mean first positive (P1) latency of 27ms. Statistical analysis showed more elongated latency for the pentobarbital group than the midazolam and ketamine groups. The results of this study suggest that the pharmacological effects of pentobarbital and midazolam on GABA neurotransmission in rabbit visual cortex may be different; another neurotransmission system, possibly cholinergic, may be involved. The ketamine effect seen in rabbit visual cortex seems to be different from pentobarbital and midazolam.

Comparison of xylazine and medotomidine as premedicants for cats being anaesthetised with propofol-sevoflurane

The effects of premedicating cats with saline, xylazine or medetomidine before anaesthetising them with propofol-sevoflurane were compared. Twenty-four cats were randomly assigned to three groups of eight to receive either 0.25 ml of saline, 0.50 mg/kg of xylazine or 0.02 mg/kg of medetomidine intravenously, and anaesthesia was induced with propofol and maintained with sevoflurane. Medetomidine produced a greater reduction in the induction dose of propofol and fewer adverse postoperative effects than saline or xylazine. Hypoxaemia was observed after induction with propofol in the cats premedicated with saline and xylazine, but not in the cats given medetomidine. The cats treated with medetomidine and xylazine developed profound bradycardia. The blood pressure of the cats premedicated with saline and xylazine decreased, but the blood pressure of the cats premedicated with medetomidine was maintained. The cats premedicated with saline took longer to recover from anaesthesia than the other two groups.

Efeitos do extrato aquoso de cebola (Allium cepa L.) sobre a função renal e a pressão arterial em ratos Wistar

The vegetal species, Allium cepa, known as onion, is widely used in the folk medicine as diuretic, besides it has been used on the bronchitis, cough, cardiovascular diseases and hypertension treatment. In this study we evaluate the onion aqueous extract (AE) effect on water flow and electrolytes in anesthetized Wistar rats, besides we also evaluate arterial pressure alterations. Two groups were studied: Group 1 (control) - oral tratment with 1.0 mL of distilled water, and Group 2 (experimental) - oral treatment with 1.0 mL of AE 20%. The rats were anesthetized and we canulate the trachea, left carotide artery (for arterial pressure measurement and blood collecting), jugular vein (to execute inulin perfusion - to register glomerular filtration), and urinary bladder (to collect urine). The Group 1 results had shown that the animals had not presented significant alterations (p>0.05) in the analyzed parameters. The animals of Group 2 had a significant reduction (p<0.05) in the arterial pressure (22.0%). However, there were not significant alterations in renal parameters (p>0.05). These results show that the treatment with the AE lead a hypotensor effect in anesthetized Wistar rats, but not followed by renal parameters alterations.

Estudo comparativo dos efeitos hemodinâmicos e ventilatórios da ventilação controlada a volume ou a pressão, em cães submetidos ao pneumoperitônio

BACKGROUND AND OBJECTIVES: Pressure controlled ventilation (PCV) is available in anesthesia machines, but there are no studies on its use during CO 2 pneumoperitoneum (CPP). This study aimed at evaluating pressure-controlled ventilation and hemodynamic and ventilatory changes during CPP, as compared to conventional volume controlled ventilation (VCV). METHODS: This study involved 16 dogs anesthetized with thiopental, fentanyl and pancuronium, which were randomly assigned to two groups: VC - volume controlled ventilation (n=8) and PC - pressure controlled ventilation (n=8). Hemodynamic and ventilatory parameters were monitored and recorded in 4 moments: M1 (before CPP), M2 (30 minutes after CPP = 10 mmHg), M3 (30 minutes after CPP=15 mmHg) and M4 (30 minutes after deflation). RESULTS: With CPP, there has been significant increase in tidal volume in PC group; there has been increase in airway pressures (peak and plateau), decrease in compliance with increase in CPP pressure, increase in heart rate, maintenance of mean blood pressure with higher values in the VC group in all stages; there was also increase in right atrium pressure with significant decrease after deflation, decrease in arterial pH with minor variations in PC group, greater arterial pCO 2 stability in PC group, and no significant changes in arterial pO 2. CONCLUSIONS: There were some differences in hemodynamic and ventilatory data between both ventilation control modes (VC and PC). It is possible to use pressure controlled ventilation during CPP, but the anesthesiologist must monitor and take a close look at alveolar ventilation, adjusting inspiratory pressure to ensure proper CO 2 elimination and oxygenation. © Sociedade Brasileira de Anestesiologia, 2005.