Reperfusion arrhythmias after chronic regional denervation of the ischaemic myocardium in pigs.

OBJECTIVE: The aim was to assess the effects of chronic regional denervation of the ischaemic myocardium on reperfusion arrhythmias in a model with sparse coronary collateral circulation. METHODS: Baseline ventricular refractoriness and epicardial activation times were measured together with reperfusion arrhythmias after 15 min (I-15') or 30 min (I-30') of left anterior descending coronary artery occlusion in 38 barbiturate anaesthetised open chest pigs. Twenty pigs (11 in I-15' and nine in I-30') had a chronic (two week) denervation of the left anteroseptal region, whereas 18 pigs (10 in I-15' and eight in I-30') were sham operated (non-denervated) controls. Denervation was induced by pericoronary application of phenol and verified by absence of adrenergic histofluorescence. RESULTS: As compared with controls, denervated pigs showed: (1) longer activation times: 20.3 (SD 5.2) ms v 16.5 (4.6) ms, p < 0.001; (2) slightly longer refractory periods: 348(28) ms v 334(27) ms; (3) a tendency to lower postreperfusion ectopic activity: ectopic beats divided by time free of ventricular tachycardia: 0.13(0.19) v 0.34(0.40) in I-15', and 0.21(0.24) v 0.39(0.44) in I-30'; (4) slower ventricular tachycardia in I-30': 140(29) beats.min-1 v 185(29) beats.min-1, p < 0.009; and (5) comparable incidence of postreperfusion ventricular fibrillation: 4/11 pigs v 2/10 in I-15', and 5/9 v 4/8 in I-30'. CONCLUSIONS: Selective chronic denervation of the ischaemic myocardium was unable to protect against malignant reperfusion arrhythmias in hearts with human-like coronary collaterals. This was confirmed at two ischaemic periods known to produce progressive catecholamine accumulation and increased adrenoceptor density in the ischaemic myocardium.     

Analysis of hepatitis B virus DNA, liver disease and influence of antibody to hepatitis C virus in anti-HBe chronic carriers.

Hepatitis B virus DNA (HBV-DNA) in serum was studied in 67 anti-HBe patients using dot-blot hybridization, a modified technique and polymerase chain reaction (PCR). All patients had abnormal aminotransferase (ALT) levels. Serum HBV-DNA was detected in 14/67 cases by dot-blot and in 39/67 (DNA probe) and 45/67 (RNA probe) using the modified technique. The RNA probe was more sensitive than the DNA probe when they were compared, using serial dilutions of HBV-DNA of known concentration (0.1 pg vs 1 pg, respectively). HBV-DNA was found by PCR in 57/67 patients. Ten patients were negative to serum HBV-DNA. The ALT level was significantly higher in patients with serum HBV-DNA by dot-blot as compared to those who had serum HBV-DNA by the modified technique and PCR. With respect to the presence of anti-HCV, 6/67 had anti-HCV confirmed by RIBA test. These 6 patients had serum HBV-DNA. The route of acquisition of HBV infection in anti-HCV positive patients was by parenteral exposure in 67% of the cases and 15% in HCV negative (p less than 0.05). All patients were negative to nonorganic specific autoantibodies. In summary, most of the anti-HBe patients (85%) had viral replication. HCV superinfection plays a minor role in the activity of liver disease.     

Differential Expression of CD30 on CD3 T Lymphocytes in Patients with Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune systemic disease caused as a result of an imbalance of Th1‐/Th2‐type cytokines. The soluble form of CD30 (CD30s) released from peripheral blood cells has been described as a marker of active disease in Th2‐type immune response as in SLE. However, the expression of CD30 on CD3 T lymphocytes from patients with SLE has not been studied yet. Therefore, we have addressed our study to attempt this issue, studying CD30 expression by flow cytometry on CD3 T lymphocytes and CD4/CD8 subsets in samples from SLE patients mainly with lupus nephritis. In parallel, we have determined the production of the cytokines IL‐4 (Th2), IFNγ (Th1), IL‐10 and TGFβ by intracellular staining. Differences between positive CD30 T cells in healthy controls and patients with SLE were found, with a higher percentage of CD30‐expressing T cells in patients with SLE (P = 0.001). In contrast to healthy controls, CD30 was mainly expressed on CD8 T cells from patients with SLE. The intracellular cytokine staining showed that TGFβ is the main cytokine expressed in CD3 T cells from patients with SLE. In addition to this, we have found a positive correlation between CD30‐expressing T cells and IL‐4, IFNγ, and immunosuppressive cytokines (IL‐10 and TGFβ) (P < 0.05). These results suggest that CD30 could play a role in the pathogenesis of SLE and its expression on CD3 T lymphocytes is not restricted only to Th2‐type response.     

Efficacy of different doses of sugammadex after continuous infusion of rocuronium

AIM: To evaluate the effects of two different doses of sugammadex after maintenance anesthesia with sevofluorane and remifentanil and deep rocuroniuminduced neuromuscular blockade(NMB).METHODS: Patients between 20 and 65 years of age, with American Society of Anesthesiologists physical status classification Ⅰ-Ⅱ, undergoing gynecological surgery were included in a prospective, comparative and randomized study. NMB was induced with an injection of 0.6 mg/kg of rocuronium followed by continuous infusion of 0.3-0.6 mg/kg per hour to maintain a deep block. Anesthesia was maintained with sevofluorane and remifentanil. Finally, when surgery was finished, a bolus of 2 mg/kg(group A) or 4 mg/kg(group B) of sugammadex was applied when the NMB first response in the train-of-four was reached. The primary clinical endpoint was time to recovery to a train-of-four ratio of 0.9. Other variables recorded were the time until recovery of train-of-four ratio of 0.7, 0.8, hemodynamic variables(arterial blood pressure and heart rate at baseline, starting sugammadex, and minutes 2, 5 and 10) and adverse events were presented after one hour in the post-anesthesia care unit.RESULTS: Thirty-two patients were included in the study: 16 patients in group A and 16 patients in group B. Only 14 patients each group were recorded because arterial pressure values were lost in two patients from each group in minute 10. The two groups were comparable. Median recovery time from starting of sugammadex administration to a train-of-four ratio of 0.9 in group A and B was 129 and 110 s, respectively.The estimated difference in recovery time between groups was 24 s(95%CI: 0 to 45 s, Hodges-Lehmann estimator), entirely within the predefined equivalence interval. Times to recovery to train-of-four ratios of 0.8(group A: 101 s; group B: 82.5 s) and 0.7(group A: 90 s; group B: 65 s) from start of sugammadex administration were not equivalent between groups. There was not a significant variation in the arterial pressure and heart rate values between the two groups and none of the patients showed any clinical evidence of residual or recurrent NMB. CONCLUSION: A dose of 2 mg/kg of sugammadex after continuous rocuronium infusion is enough to reverse the NMB when first response in the Train-OfFour is reached.     

Purging of acute myeloid leukemic cells by ether lipids and hyperthermia

Ether lipids (EL) and hyperthermia have been shown to possess a relatively selective cytotoxicity to leukemic cells. In this study, the combined effects of EL (ET-18-OCH3, ET-16-NHCOCH3, or BM 41.440) and hyperthermia on the growth of hematopoietic progenitors, myeloid leukemic cell lines, and leukemic cells obtained from patients with acute myeloid leukemia (AML) were examined to determine if this combination resulted in a greater selective killing of leukemic cells than that achieved by either EL or heat alone. When the cells were treated simultaneously with EL (50 micrograms/mL) and hyperthermia (42 degrees C) for one hour, the killing of leukemic cell line cells was enhanced considerably. Among the three EL, however, the combination of ET-18-OCH3 and heat seemed to be the most cytotoxic to leukemic cell line cells with no effect on the growth of hematopoietic progenitors. An increase in the duration of treatment with ET-18-OCH3 to four hours with heat added during the last hour resulted in a further reduction of leukemic cell line cells while sparing 50% of hematopoietic progenitors after cryopreservation. The combined treatment with ET-18-OCH3 and heat also inhibited the growth of leukemic progenitors obtained from AML patients by 97% to 100%. These data indicate that the combined treatment with EL and hyperthermia might offer an efficient means to eliminate myeloid leukemic cells in vitro.     

Cathepsin L1 mimotopes with adjuvant Quil A induces a Th1/Th2 immune response and confers significant protection against Fasciola hepatica infection in goats

Thirty goats were randomly allocated in five groups of six animals each, for immunization with 1?×?10¹⁴ phage particles of clones 11, 13, and 13 with Quil A adjuvant and wild-type M13KE phage at the beginning and 4 weeks later. The control group received phosphate-buffered saline. All groups were challenged with 200 metacercariae at week 6 and slaughtered 14 weeks later. The mean worm burdens after challenge were reduced by 46.91 % and 79.53 % in goats vaccinated with clones 13 and 13 with Quil A (P?<?0.05), respectively; no effect was observed in animals immunized with clone 11 and M13KE phage. Animals receiving clones 11, 13, and 13 with Quil A showed a significant reduction in eggs output. Vaccinated animals produced parasite-specific total IgG antibody which were boosted after challenge with metacercariae of F. hepatica. Furthermore, levels of anti-phage total IgG increased rapidly within 2 weeks of the first vaccination and were always significantly higher in all vaccinated goats than in the infected control group. The fluke burden of goats immunized with clones 13 and 13 with Quil A was significantly correlated with IgG2 and total IgG. Goats vaccinated with phage clones produced significantly high titres of IgG1 and IgG2 antibodies indicating a mixed Th1/Th2 response. These data indicate that cathepsin L1 mimotopes has a potential as a vaccine candidate against Fasciola hepatica, whose efficacy will be evaluated in other host species, including those of veterinary importance.