Lack of association between the incidence of testicular germ cell tumors and Y-chromosome haplogroups in the Japanese population

BACKGROUND: Despite being relatively uncommon, testicular germ cell tumors (TGCT) are the most common malignant disease in young men. Epidemiological studies concerning patients with testicular cancer indicate that the most of them have poor semen quality or testicular dysgenesis. However, many studies have shown that the Y chromosome harbors many candidate genes responsible for spermatogenesis process and development and maintenance of the germ cells. The Y chromosome is thought to have a relationship with the formation and progression of TGCT. MATERIALS AND METHODS: To verify this relationship, we investigated if there is any correlation between the Y chromosome structural variations presented as different haplogroups and the occurrence of TGCT in the Japanese population. Using combined haplogroups based on typing of three Y chromosome polymorphic binary markers, we analyzed 68 TGCT derived from Japanese patients together with randomly selected 104 unrelated healthy Japanese matched male controls who were confirmed as residents of the same geographic area. RESULTS: Our findings showed a lack of association between the incidence of TGCT and the different Y- chromosome haplogroups in Japanese population. CONCLUSION: We concluded that there are no significant variations in males from different Y chromosome lineages regarding their susceptibility or resistance for developing TGCT. The previously hypothesized role of the Y chromosome in the development of TGCT is still uncertain and needs further verification.     

Transcytotic vesicle fusion with canalicular membranes is modulated by phospholipid species: Implications for biliary lipid secretion

Phospholipid species modulate bile metastability and the subselection of such species for biliary secretion occurs at the canalicular membrane. In this study, the role of phospholipid head groups and hydrophobic indices in transcytotic vesicle fusion with the canalicular membrane inner leaflet was investigated using rat canalicular membrane vesicles (CMV) and liposomes. The CMV were purified from Sprague-Dawley rat liver, and small unilamellar vesicles (SUV) of phosphatidylserine (PS), phosphatidylcholine (PC) and mixtures of PS/PC (1:1, 2:1 and 4:1) were labelled with 8 mol% of octadecyl rhodamine B chloride (R18). The PC species used in this study were egg yolk PC (EYPC), soybean PC (SBPC), dipalmitoyl PC (DPPC) and dilinoleoyl PC (DLPC). Fusion of SUV with CMV was initiated by the addition of a millimolar concentration of Ca²⁺ and the degree of fusion was estimated by the increase of R18 fluorescence. Ca²⁺-dependent fusion of SUV consisting of PS, and PS/PC (4:1) with CMV was observed (PS > PS/PC; 4:1), whereas no detectable fusion was evident between CMV and SUV of PC alone or PS/PC (1:1 or 2:1). The rank order of fusibility between CMV and SUV of PS/PC (4:1) containing various PC species was PS/DLPC > PS/SBPC > PS/EYPC > PS/DPPC. The hydrophobic index of PC as determined by high performance liquid chromatography (HPLC) was related closely to liposome fusibility (r=-0.88). These results suggest that transcytotic vesicie fusion with the canalicular membrane inner leaflet is regulated by the phospholipid hydrophobicity of the vesicles.     

Acute hepatitis C among renal failure patients on chronic haemodialysis

Hepatitis C virus (HCV) infection is common in haemodialysis units, yet little information is available about the clinical feature of acute hepatitis C among renal failure patients. The present study is based on 49 cases of acute hepatitis C seen at a haemodialysis centre where sporadic nosocomial infection was occurring up to June 1993. Liver function tests were done at 4 weekly intervals on all dialysis patients, anti-HCV antibodies were tested by the C-100 and second generation tests and serum HCV-RNA was determined by the branched DNA and Amplicore tests. Diagnosis of acute hepatitis C was made on the basis of an acute rise in alanine aminotransferase (ALT) and seroconversion to positive anti-HCV antibodies. Clinical presentation of acute hepatitis was generally mild with rare overt jaundice and the diagnosis was possible only from increased ALT, which was generally low. Spontaneous resolution of acute hepatitis within 8 months with clearance of viral RNA occurred in only four cases, 91.8% of patients developing chronic hepatitis. Biopsy in 12 cases with high ALT levels showed mild to moderate inflammatory activities. In conclusion, the clinical presentation of acute hepatitis C is generally mild in chronic haemodialysis patients, but spontaneous resolution is infrequent. A longer follow-up period is required for defining the long-term prognosis.     

Evaluation of Oral Mucoadhesive Microspheres in Man on the Basis of the Pharmacokinetics of Furosemide and Riboflavin,Compounds with Limited Gastrointestinal Absorption Sites

When sustained-release adhesive and non-adhesive microspheres which release the same drugs at similar rates are administered orally, drug absorption after administration of adhesive microspheres should, if the gastrointestinal residence of adhesive microspheres is prolonged as a result of mucoadhesion, be higher than that after administration of non-adhesive microspheres. The gastrointestinal transit of oral adhesive microspheres in man has been evaluated pharmacokinetically using furosemide and riboflavin, compounds with limited absorption sites in the upper small intestine. In a preliminary experiment with fasted rats it was confirmed that a higher percentage of the drug remained in the stomach and that plasma drug levels were higher when furosemide was administered in the form of adhesive rather than non-adhesive microspheres. Two kinds of sustained-release microsphere, adhesive and non-adhesive, containing furosemide and riboflavin in hard gelatin capsules were prepared and orally administered to 10 healthy fasted volunteers in a cross-over design. Areas under the plasma concentration-time curves (AUC) were 1.8 times larger for furosemide and urinary recovery was 2.4 times higher for riboflavin when adhesive microspheres rather than when non-adhesive microspheres were used. When adhesive microspheres containing riboflavin were administered to fed volunteers, urinary recovery was 2.1 times higher and mean residence time (MRT) was more prolonged than when the microspheres were administered to fasted volunteers. Adhesive microspheres were found to adhere to the gastric or intestinal mucosa with high affinity in man and rats, resulting in prolonged gastrointestinal residence.     

Prevalence of tobacco smoking among junior high school students in Japan and background life style of smokers

In order to estimate the prevalence of tobacco smoking among junior high school students in Japan and to assess certain characteristics of smokers, the authors surveyed 5240 students aged between 12 and 15 years. In terms of both the number of subjects and of schools, this was the first major survey of Japanese junior high schools on the relationship between tobacco smoking and the background life styles of smokers. Of all students, 30.5% of males, 13.3% of females and 22.2% of the total were lifetime smokers; 3.3%, 0.8% and 2.2%, respectively, were daily smokers. As the frequency of tobacco smoking increased, the regularity of the life style routine was significantly more disturbed, and school and family life were significantly less relaxed. The authors suggest that the strengthening of family cohesion would be an effective preventive strategy in Japan.     

Hepatectomy for Metastatic Liver Tumor

Hepatectomy for liver metastasis front the colo-rectum and otherorgans was performed in 77 cases at the National Cancer CenterHospital. The operative procedures included every variety ofhepatectomy from extended resection as trisegmenlectomy to smallresection as partial resection. The operative mortality ratewas 3.9% (3/77). The overall cumulative 5-year survival ratewas 26.7 ± 13.9% (survival rate ± Greenwood's5% standard error). The long-term survival of the patients withunilobular metastasis (H₁) was better than that of bilobular(H₂) and disseminated (H₄ metastasis). When H₁ was divided intosolitary unilobular metastasis (H₁ solitary) and multiple unilobularmetastasis (H₁ multiple), the prognosis for the former was betterthan for the latter after hepatectomy. The long-term survivalof patients with H₁ multiple was the same as that of patientswith H₂ and H₃ that means that one of the factors affectingprognosis after hepatectomy is whether the tumor is solitaryor multiple.     

Unusual Mechanism in the Initiation of the Paroxysmal Supraventricular Tachycardia in a Patient with WPW Syndrome

A heretofore unreported unusual mechanism in the initiation of the paroxysmal supraventricular tachycardia (PSVT) in a patient with WPW (Wolff-Parkinson-White) syndrome was observed using His bundle recordings. The patient initially had some degree of AV conduction disturbance at the level of the AV node. A premature atrial impulse initially activated the ventricle exclusively through the accessory pathway and the same impulse re-excited the ventricle via the AV nodal-His axis after finishing the pure pre-excitation with marked prolongation of the AH and the HV intervals. After finishing this double ventricular response it traversed to the atrium to produce the PSVT.     

Sensitivity to cisplatin determined by the histoculture drug response assay and clinical response of endometrial cancer

This study investigated the value of the in vitro histoculture drug response assay (HDRA) for predicting the efficacy of chemotherapy in patients with endometrial cancer. Specimens were obtained from 115 patients with endometrial cancer treated at Keio University Hospital between 1994 and 2002. Tumor fragments were cultured on collagen sponge gel with cisplatin for 7 days, and cell viability was assessed. The cutoff value of the 50% inhibitory concentration of cisplatin was set at 23 microg/mL. Sensitivity of stage III or IV disease to chemotherapy was investigated, and differences of 5-year progression-free survival between patients with sensitive and resistant tumors were evaluated by the Kaplan-Meier method. Tumors were evaluable in 93.0% of patients (107/115). Among 38 patients in stages III or IV, 23 received chemotherapy containing cisplatin. Seven sensitive tumors did not recur, while recurrence/progression occurred within 6 months in 8/16 patients with tumors showing low sensitivity. Among stages III and IV patients, there was a significant difference of 5-year progression-free survival (P < 0.05) between those with tumors showing high or low sensitivity. Accordingly, the HDRA may predict the efficacy of chemotherapy for endometrial cancer.     

Characterization of the recognition specificity of autoreactive, polyspecific monoclonal antibodies obtained from spleen cells of parasite-infected BALB/c mice

We examined the specificity of four monoclonal antibodies (MoAbs) obtained from Schistosoma japonicum (1D, GAO3), Trypanosoma cruzi (TSLO), and Trichinella spiralis (TSY2) infected BALB/c mice. All four MoAbs reacted not only with autologous parasite antigens but also with various heterologous parasite antigens and normal tissues. The antigen recognition pattern seen on Western blots was almost identical in 1D and GAO3, and in TSLO and TSY2. Furthermore, certain bands were identical among all four MoAbs. The mechanisms responsible for these phenomena are discussed.     

Early Cancer of the Stomach Treated Successfully with an Endoscopic Neodymium-YAG Laser

A 61-year old man with poor pulmonary function was seen with two early cancers of the stomach. Neodymium-YAG laser treatment was applied to these lesions since surgery was contraindicated. The lesions were treated four times. Both tumors completely disappeared and the patient was left with ulcer scars that formed three to seven months after the treatment. Our results suggest that endoscopic Nd-YAG laser therapy is applicable in the treatment of early gastric cancer when a surgical operation is contraindicated.