Catheter Ablation of Accessory Atrioventricular Connection between Right Atrial Appendage to Right Ventricle

Accessory AV Connection Between RAA and RV. A 24-year-old woman had experienced frequent attacks of orthodromic AV reciprocating tachycardia. The polarity of the delta waves suggested a right anterior or anterolateral accessory pathway. After ablation at the tricuspid annulus was unsuccessful, earliest retrograde atrial activation was recorded on the floor of the right atrial appendage, 2 cm above the tricuspid ring. Application of radiofrequency en-ergy at this site aholished accessory pathway conduction. This unusual accessory pathway, located between the floor of the right atrial appendage and the right ventricle, was amenable to radiofrequency catheter ablation from within the right atrial appendage.     

Proliferative activity in intrahepatic metastasis of hepatocellular carcinoma

To assess the characteristics of intrahepatic metastatic lesions (IML) in hepatocellular carcinoma (HCC), we analysed both the histological features and proliferative activities of 15 resected cases of HCC accompanied by IML. The histological features of the IML were essentially the same as those observed in the main nodules in 12 (80%) of 15 cases. In 13 (87%) of 15 cases, the labelling index of proliferating cell nuclear antigen (PCNA) in the IML was either higher than or the same as in the main nodules. In 10 (77%) of 13 cases, the MIB-1 labelling index in the IML was either higher than or the same as in the main nodules. The results indicate that the histological features of the IML are essentially the same as those of the main nodules, while the proliferative activities in the IML were generally higher than those in the main nodules. Such characteristics may thus provide a clue to help distinguish intrahepatic metastasis from the multicentric occurrence of HCC.     

Effect of obstructive jaundice on neutrophil chemotactic activity: An in vivo assessment in zymosan-induced peritonitis model in rats

The effect of obstructive jaundice on local neutrophil accumulation in response to inflammatory stimulus was investigated in rats. Obstructive jaundice was produced by bile duct ligation for 7 days. Zymosan (200 mg) was injected intraperitoneally and 4h later myeloperoxidase activity in the peritoneal fluid was measured to quantify neutrophil recruitment. Zymosan-induced neutrophil recruitment was significantly greater (more than two-fold) in bile duct-ligated rats than in sham-ligated or normal animals. Depletion of peritoneal cells significantly suppressed neutrophil recruitment after zymosan injection in all three groups, with no significant differences between the groups. In normal rats, replacement of their peritoneal cells by those from bile duct-ligated rats did not enhance zymosan-induced neutrophil recruitment. In contrast, bile duct-ligated rats treated with peritoneal cell replacement from normals showed significantly increased neutrophil recruitment after zymosan injection. In vitro neutrophil chemotaxis in response to formyl-Met-Leu-Phe was significantly enhanced in bile duct-ligated rats, compared with that in sham-ligated animals. The results suggest that local neutrophil recruitment in response to inflammation may be enhanced in obstructive jaundice and that increased neutrophil chemotactic activity, not macrophage activity, may play a prime role in the mechanism.     

CASE REPORT: Alanine aminotransferase deficiency detected in a patient with chronic hepatitis C

We report a case of alanine aminotransferase (ALT) deficiency in a 68-year-old Japanese female with chronic hepatitis C. The serum was positive for antibody to hepatitis C virus (HCV) and HCV-RNA. Liver biopsy showed histological evidence of chronic active hepatitis. The level of serum aspartate aminotransferase (sAST) was elevated, but sALT was extremely low. The patient was followed up for her serum aminotransferase levels for 1.5 years under the treatment with ursodeoxycholic acid. The low sALT level persisted during all the follow-up period. The ALT activity in liver tissue was also decreased. Based on these findings, ALT deficiency was suspected. sALT activity was also found to be low in her two sons. This latter finding suggests the hereditary character of this abnormality.     

Frequency of Diplopia after Intraoperative Nerve Disturbance in Trochlear Nerve Schwannoma: A Case Report and Systematic Review

Schwannomas of the trochlear nerve are relatively rare, and most patients present with preoperative diplopia because of trochlear nerve palsy. We describe the case of a 61-year-old male patient with a trochlear nerve schwannoma and no pre- and postoperative diplopia, despite his trochlear nerve being cut during the operation. We aimed to investigate the frequency of postoperative diplopia associated with intraoperative trochlear nerve disturbance by reviewing previous case reports, wherein postoperative diplopia did not occur after the trochlear nerve was cut intraoperatively. We recorded the frequency of diplopia because of intraoperative trochlear nerve disturbance, such as the trochlear nerve being cut, in cases without pre- and postoperative diplopia. We searched the PubMed, Medline, and Google Scholar databases for works published from 1976 to 2020 and followed the preferred reporting items for systematic reviews and meta-analyses guidelines. We reviewed 36 publications and found 92 cases of trochlear nerve schwannoma. Surgical resection was performed for 43 patients, of whom 40 were kept under observation and 9 were treated with radiation therapy. Of the 43 cases, 9 without preoperative diplopia underwent gross total resection. We analyzed ten cases (including ours) without preoperative diplopia to check for postoperative diplopia. In total, four cases, including ours, did not display postoperative diplopia despite the trochlear nerve being cut. This may be attributed to the preoperatively acquired motor and sensory fusion in the patient’s vision because of tumor progression. Our findings may benefit neurosurgeons who treat patients with schwannomas and help them predict patients’ outcomes.     

3’-当归酰氧基-4’-乙酰氧基-3’,4’-双氢邪蒿内酯对麻醉犬短时缺血后心肌功能不良的影响(英文)

静脉输入3’-当归酰氧基-4’-乙酰氧基-3’,4’-双氢邪蒿内酯(0.15mg·kg~(-1)·min~(-1))30min对15min闭塞犬左前降枝伴3h再灌注后心肌收缩功能的影响被研究。用超声微测距法测定心肌节段收缩(SS)长度表明:该药迅速改善心肌收缩功能不良,再灌后5min即使SS％恢复到用药前的41±51％(P<0.05,n=8),对血流动力学无明显影响。     

Limitations of the Severe Combined Immunodeficiency (SCID) Mouse Model for Study of Human B-Cell Responses

Mice lacking functional T and B lymphocytes offer an in vivo animal model for the study of human immune functions. We have attempted to optimize the reconstitution of severe combined immunodeficiency (SCID) mice with human peripheral blood lymphocytes (PBL) using radiation, anti-asialo GM₁ antibody or cyclophosphamide (Cy) treatment of the mice and in vitro stimulation of human PBL with interleukin (IL)-2 prior to their transfer to the mice. Total human IgG and tetanus-toxoid (TT)-specific human IgG responses of the mice were used as parameters of successful reconstitution. Treatment of the mice with anti-asialo GM₁ antibody significantly enhanced total human IgG levels, but not TT-specific antibody responses, whereas irradiation or Cy treatment of the mice had no effect on human antibody production. In vitro treatment of human PBL with IL-2 prior to engraftment significantly decreased total human IgG responses of human PBL-grafted SCID mice. The immune responses of individual mice within a group were highly variable, which constitutes a major disadvantage of this model.