Central antioxidant therapy inhibits parasympathetic baroreflex control in conscious rats.

Baroreceptor reflex is an important system for neural control of blood pressure. Recently, reactive oxygen species (ROS) have been shown to play an important role in neuronal activity of central areas related to blood pressure control. The aim of this study was to investigate the effects elicited by ascorbic acid (AAC) and N-acetylcysteine (NAC) injections into the 4thV on the parasympathetic component of the baroreflex. Male Wistar rats were implanted with a stainless steel guide cannula into the 4thV. One day prior to the experiments, the femoral artery and vein were cannulated for pulsatile arterial pressure, mean arterial pressure and heart rate measurements and drug administration, respectively. After baseline recordings, the baroreflex was tested with a pressor dose of phenylephrine (PHE, 3 µg/kg, i.v.) and a depressor dose of sodium nitroprusside (SNP, 30 µg/kg, i.v.) before (control) and 5, 15, 30 and 60 min after AAC or NAC into the 4thV. Control PHE injection induced baroreflex-mediated bradycardia (-93 ± 13 bpm, n=7). Interestingly, after AAC injection into the 4thV, PHE injection produced a transient tachycardia at 5 (40 ± 23 bpm), 15 (26 ± 22 bpm) and 30 min (59 ± 21 bpm). No changes were observed in baroreflex-mediated tachycardia evoked by SNP after AAC injection on 4thV (control: 151 ± 23bpm vs. 135 ± 18 bpm at 5 min after AAC, n=7). In the NAC treated group, PHE induced a reduction in reflex bradycardia at 5 min when compared to control (-11 ± 17 bpm vs. -83 ± 15 bpm, n=7). No changes were observed in baroreflex-mediated tachycardia evoked by SNP after NAC injection on 4thV. The antioxidants AAC and NAC may act in the central nervous system affecting the parasympathetic component of the cardiac baroreflex.

Levels of carcinoembryonic antigen and CA 19-9 in the sera and peritoneal washing of patients undergoing surgical treatment for gastric carcinoma.

BACKGROUND: Early peritoneal recurrence of gastric carcinoma following curative resection remains a great challenge in the treatment and prevention of this disease. AIM: To analyze the relationship between levels of tumor markers, carcinoembryonic antigen (CEA) and CA 19-9 in the sera and peritoneal washing, and anatomopathological aspects of the gastric carcinoma. METHODS: Of the 46 patients in the study, 29 (63.0%) were males and 17 (37.0%) females. Mean age was 63.6 +/- 11.7 years (31 to 91 years). Peripheral venous blood samples were collected from the upper limb vein from both patient groups after anesthetic induction, in order to determine serum levels of CEA and CA 19-9. After the end of the procedure, 50 mL of physiologic solution was introduced into the bottom of the Douglas sack and a portion aspirated to determine CEA and CA 19-9 levels in the peritoneal washing. Levels of CEA and CA 19-9 in the sera and peritoneal washing were compared to the following variables: lesion diameter < or = 4 cm or > 4 cm, lymph node involvement, angiolymphatic invasion, depth of invasion into gastric wall, and initial or late stage. RESULTS: Sera CEA levels were significantly higher in patients with lesions >5 cm. CEA levels in the sera and peritoneal washing were significantly greater in patients with signet ring cell gastric carcinoma. In addition, levels of CEA in peripheral blood and peritoneal washing showed significant association with the degree of carcinoma penetration into the gastric wall, while sera CEA was significantly higher in patients at more advanced stages. There was no significant difference between sera and peritoneal CEA values regarding grade of differentiation. Patients with gastric lesions measuring > 5 cm and more differentiated lesions had significantly higher sera CA 19-9 values. In patients with lymph nodes invasion by gastric carcinoma, CA 19-9 levels in peritoneal washing were significantly higher than in peripheral blood. Levels of CA 19-9 in peritoneal washing were significantly greater at advanced stages than the initial stage of the gastric carcinoma. CONCLUSIONS: Elevated levels of CA 19-9 in peritoneal washing were significantly associated with more advance stages of gastric carcinoma and was more reliable predictive factor for staging than sera CA 19-9 levels. CEA levels in the sera more accurately reflected neoplasia stage than levels in peritoneal washing.

Levels of carcinoembryonic antigen and CA 19-9 in the sera and peritoneal washing of patients undergoing surgical treatment for gastric carcinoma / Níveis do antígeno carcinoembriônico e do CA 19-9 no soro e no lavado peritonial em doentes submetidos ao tratamento cirúrgico do carcinoma gástrico

BACKGROUND: Early peritoneal recurrence of gastric carcinoma following curative resection remains a great challenge in the treatment and prevention of this disease. AIM: To analyze the relationship between levels of tumor markers, carcinoembryonic antigen (CEA) and CA 19-9 in the sera and peritoneal washing, and anatomopathological aspects of the gastric carcinoma. METHODS: Of the 46 patients in the study, 29 (63.0 percent) were males and 17 (37.0 percent) females. Mean age was 63.6 ± 11.7 years (31 to 91 years). Peripheral venous blood samples were collected from the upper limb vein from both patient groups after anesthetic induction, in order to determine serum levels of CEA and CA 19-9. After the end of the procedure, 50 mL of physiologic solution was introduced into the bottom of the Douglas sack and a portion aspirated to determine CEA and CA 19-9 levels in the peritoneal washing. Levels of CEA and CA 19-9 in the sera and peritoneal washing were compared to the following variables: lesion diameter ≤4 cm or >4 cm, lymph node involvement, angiolymphatic invasion, depth of invasion into gastric wall, and initial or late stage. RESULTS: Sera CEA levels were significantly higher in patients with lesions >5 cm. CEA levels in the sera and peritoneal washing were significantly greater in patients with signet ring cell gastric carcinoma. In addition, levels of CEA in peripheral blood and peritoneal washing showed significant association with the degree of carcinoma penetration into the gastric wall, while sera CEA was significantly higher in patients at more advanced stages. There was no significant difference between sera and peritoneal CEA values regarding grade of differentiation. Patients with gastric lesions measuring > 5cm and more differentiated lesions had significantly higher sera CA 19-9 values. In patients with lymph nodes invasion by gastric carcinoma, CA 19-9 levels in peritoneal washing were significantly higher than in ...

RACIONAL: A recidiva peritonial precoce do carcinoma gástrico operado com intenção curativa continua sendo um grande desafio do seu tratamento e prevenção. OBJETIVO: Analisar a relação entre os níveis do marcador tumoral antígeno carcinoembriônico (CEA) e CA 19-9 no sangue e no lavado peritonial e os aspectos anatomopatológicos do carcinoma gástrico. MÉTODO: Dos 46 doentes do estudo, 29 (63,0 por cento) eram do sexo masculino e 17 (37,0 por cento) do feminino. A média de idade foi de 63,6 ± 11,7 anos (31 a 91 anos). Após a indução anestésica, o sangue venoso periférico foi coletado de veia do membro superior para a determinação do nível sérico do CEA e CA 19-9. Após o término do procedimento operatório foram derramados 50 mL de solução fisiológica no fundo de saco de Douglas, aspirada alíquota que foi encaminhada para a determinação do nível no lavado peritonial do CEA e CA 19-9. O nível do CEA e do CA 19-9 sérico e no lavado peritonial foram relacionados às seguintes variáveis: diâmetro da lesão ≤4 cm ou >4 cm, comprometimento linfonodal, invasão angiolifática, profundidade de invasão na parede gástrica e estádio inicial ou tardio. RESULTADOS: Em relação ao CEA, o nível sérico foi significantemente maior nos doentes com o diâmetro da lesão >5 cm. O nível de CEA sérico e no lavado peritonial foi significantemente maior nos doentes com carcinoma gástrico com células em anel de sinete. O nível de CEA no sangue periférico e no lavado peritonial mostrou relação significante com o nível de penetração do carcinoma na parede gástrica, e o CEA sérico foi significantemente mais elevado nos doentes com estádio mais avançados. Não houve diferença significante entre os valores do CEA sérico e peritonial nos carcinomas mais diferenciados em relação aos menos diferenciados. No tocante ao CA 19-9, os enfermos com lesões gástricas com diâmetro >5 cm e mais diferenciadas exibiram valores séricos de CA 19-9 significantemente maiores. Nos doentes ...