155 ESTABLISHMENT OF AN IN VITRO FERTILIZATION PROTOCOL USING CRYOPRESERVED EPIDIDYMAL AND EJACULATED RAT SPERMATOZOA

In rats, successful IVF with cryopreserved rat sperm has never been reported. The objective of the present study was to establish and improve the IVF protocol using epididymal and ejaculated rat spermatozoa after cryopreservation. At first, we examined whether cryopreserved ejaculated spermatozoa would be useful for IVF in Wistar rats. Capacitation-associated tyrosine phosphorylation was accelerated in frozen-thawed ejaculated sperm in a time-dependent manner. These frozen-thawed spermatozoa were co-cultured with cumulus–oocyte complexes in modified R1ECM for 10 h. The putative zygotes were transferred to R1ECM and then cultured up to 144 h. Although the rates of insemination and 2 pronucleus (2PN) formation were low (26.5 and 23.0%, respectively), most of 2PN oocytes were developed to the 2-cell stage (91.0%). A total of 44 embryos at the 2-cell stage derived from frozen-thawed ejaculated sperm were transferred to 5 recipient females and 21 pups (47.7%) were delivered. Next, we used frozen-thawed epididymal spermatozoa for IVF in Wistar rats. After thawing, intracellular cyclic adenosine monophosphate (cAMP), free cholesterol levels and capacitation-associated protein tyrosine phosphorylation levels of the sperm were assayed. Intracellular cAMP and free cholesterol levels in frozen-thawed epididymal sperm were maintained at a low level, suppressing capacitation-associated tyrosine phosphorylation. Treatment with a phosphodiesterase inhibitor, 3-isobutyl-1-methyl-xanthin (IBMX) dramatically increased cAMP and capacitation-associated tyrosine phosphorylation levels in frozen-thawed epididymal sperm. When the IBMX-treated frozen-thawed sperm was used for IVF, the proportions of 2PN and the development to blastocysts were significantly higher (approximately 40 and 20%, respectively) than those of frozen-thawed epididymal sperm treated without IBMX (approximately 10 and 3%, respectively). These embryos were developed to term at a high success rate (49%) equivalent to the rate obtained with IVF using fresh sperm (58%). Moreover, we tried to apply our IVF system to inbred rat strains [Fischer 344 (F344) and Brown-Norway (BN)]. We examined whether the IVF protocol was available for F344 and BN rats. Fresh and frozen-thawed sperm collected from cauda epididymides in F344 and BN were used for detection of capacitation-associated tyrosine phosphorylation. In fresh F344 sperm, capacitation-associated tyrosine phosphorylation was induced in a time-dependent manner. Although tyrosine phosphorylation was inhibited in frozen-thawed F344 sperm, it was dramatically accelerated by IBMX treatment as well as frozen-thawed Wistar sperm. However, tyrosine phosphorylation in fresh and frozen-thawed BN sperm was suppressed and the phosphorylation in frozen-thawed sperm was not improved by IBMX. Taken together, we developed an IVF protocol using cryopreserved rat sperm and our data suggest that the IVF system can be applied not only to Wistar rats but also to the F344 strain. This research was also partially supported by a research project grant awarded by the Azabu University Research Services Division.

Prevalence of hyperthyroidism after exposure during childhood or adolescence to radioiodines from the chornobyl nuclear accident: dose-response results from the Ukrainian-American Cohort Study

Relatively few data are available on the prevalence of hyperthyroidism (TSH concentrations of <0.3 mIU/liter, with normal or elevated concentrations of free T4) in individuals exposed to radioiodines at low levels. The accident at the Chornobyl (Chernobyl) nuclear plant in Ukraine on April 26, 1986 exposed large numbers of residents to radioactive fallout, principally to iodine-131 ((131)I) (mean and median doses  =  0.6 Gy and 0.2 Gy). We investigated the relationship between (131)I and prevalent hyperthyroidism among 11,853 individuals exposed as children or adolescents in Ukraine who underwent an in-depth, standardized thyroid gland screening examination 12-14 years later. Radioactivity measurements taken shortly after the accident were available for all subjects and were used to estimate individual thyroid doses. We identified 76 cases of hyperthyroidism (11 overt, 65 subclinical). Using logistic regression, we tested a variety of continuous risk models and conducted categorical analyses for all subjects combined and for females (53 cases, n  =  5,767) and males (23 cases, n  =  6,086) separately but found no convincing evidence of a dose-response relationship between (131)I and hyperthyroidism. There was some suggestion of elevated risk among females in an analysis based on a dichotomous dose model with a threshold of 0.5 Gy chosen empirically (OR  =  1.86, P  =  0.06), but the statistical significance level was reduced (P  =  0.13) in a formal analysis with an estimated threshold. In summary, after a thorough exploration of the data, we found no statistically significant dose-response relationship between individual (131)I thyroid doses and prevalent hyperthyroidism.

Effect of chlorine substitution on the biodegradability of polychlorinated biphenyls

Thirty-one isomers of polychlorinated biphenyl (PCB) were examined for biodegradability by two species of Alcaligenes and Acinetobacter. The following relationships between chlorine substitution and biodegradability of PCBs were observed. (i) Degradation decreased as chlorine substitution increased. PCB isomers containing more than four chlorines were less susceptible to degradation. (ii) PCBs containing two chlorines on either the ortho position of a single ring (i.e., 2,6-) or on both rings (i.e., 2,2'-) showed very poor degradability. (iii) PCBs containing all chlorine atoms on only a single ring were generally degraded faster than when the same number of chlorines were substituted on both rings. (iv) Preferential ring fission of the molecules occurred with nonchlorinated or lesser chlorinated rings. (v) The formation and accumulation of a yellow intermediate was always observed in 4'-chloro-substituted PCBs. (vi) Significant differences between the two organisms with respect to degradability were not observed except for 2,4,6-trichlorobiphenyl.

Enrichment of marine anammox bacteria from seawater-related samples and bacterial community study

Anaerobic ammonium oxidation (anammox) is a novel nitrogen pathway catalyzed by anammox bacteria which are obligate anaerobic chemoautotrophs. In this study, enrichment culture of marine anammox bacteria (MAAOB) from the samples related to seawater was conducted. Simultaneous removal of ammonium and nitrite was confirmed in continuous culture inoculated with sediment of a sea-based waste disposal site within 50 days. However, no simultaneous nitrogen removal was observed in cultures inoculated with seawater-acclimated denitrifying sludge or with muddy sediment of tideland even during 200 days. Nitrogen removal rate of 0.13 kg/m(3)/day was achieved at nitrogen loading rate of 0.16 kg/m(3)/day after 320th days in the culture inoculated with the sediment of waste disposal site. The nitrogen removal ratio between ammonium nitrogen and nitrite nitrogen was 1:1.07. Denaturing gradient gel electrophoresis (DGGE) analysis indicated that an abundance of the bacteria close to MAAOB and coexistence of ammonium oxidizing bacteria and denitrifying bacteria in the culture.

[Cardiac surgery in an octogenarian with idiopathic thrombocytopenic purpura: report of a case]

An 81-year-old woman was referred to our hospital for surgical treatment for mitral valve regurgitation, tricuspid valve regurgitation and atrial fibrillatory bradycardia. The platelet count on admission was 4.9 x 10(4)/microl. and the results of other studies were compatible with idiopathic thrombocytopenic purpura. Although we performed high-dose transvenous immunoglobulin infusion (400 mg/kg/day) for 5 consecutive days, the platelet count showed no remarkable change. Because of progression of heart failure, we underwent cardiac operation under thrombocytopenic condition. Intra and post-operative platelet transfusion might contribute to postoperative course uneventful without bleeding tendency. In this case, high-dose immunoglobulin therapy was not effective. However the operative course was satisfactory with adequate surgical hemostasis and platelet transfusion.

[Anomalous origin of the right coronary artery from the ascending aorta]

The patient was a 77-year-old man. In June 2008, he underwent off-pump coronary artery bypass (OPCAB) for unstable angina Intraoperative epiaortic echo showed an anomalous origin of theright coronary artery from the ascending aorta 4 cm above the sinotubular junction (STJ). The right coronary artery traveled through the planned proximal anastomotic site of the saphenous vein graft (SVG). If diagnosis of the anomalous origin of the right coronary artery had not been made, there would have been a high likelihood that the right coronary artery could have been injured. Thus, the usefulness of epiaortic echo was reaffirmed. An anomalous origin of the coronary artery is a rare congenital anomaly and its incidence is approximately 1%. An anomalous origin of the right coronary artery is very rare from the ascending aorta 4 cm above the STJ and only a few cases have been reported. An anomalous origin of the coronary artery can cause serious complications affecting the prognosis after open heart surgery. Thus, such an anomalous origin needs to be considered in preoperative evaluation.

[Aortitis syndrome with repeated restenoses of a drug eluting stent]

The patient was a 49-year-old female who developed acute myocardial infarction of the right coronary artery in August 2005. In a short period of time, the patient had restenosis repeatedly after percutaneous coronary intervention (PCI). Restenosis could not be prevented even with a drug eluting stent (DES), and thus, off-pump coronary artery bypass grafting (OPCAB) was performed. The diagnosis of aortitis syndrome was made due to protracted postoperative inflammation. Aortitis syndrome was determined to be the main cause of repeated restenosis. This case was a middle-aged female who had restenosis in a short period of time, and aortitis syndrome should have been included in the differential diagnosis. Although some positive results have been reported on DES placement for coronary lesions of aortitis syndrome, DES was completely ineffective in our patient. Further studies with more patients are necessary to examine the effectiveness of DES.

Recent trends in the incidence and lifetime risk of hip fracture in Tottori, Japan

SUMMARY

Hip fracture incidence from 2004 to 2006 in the Tottori prefecture of Japan was investigated and compared with previously reported rates. The age- and gender-specific incidence of hip fracture in the Tottori prefecture has not plateaued, as has been reported for populations in Northern Europe or North America.

INTRODUCTION

Recent data from Northern Europe and North America indicate that the incidence of hip fracture has plateaued, whereas most reports from Asia indicate that the incidence is increasing. The aims of this study were to investigate the recent incidence of hip fracture in the Tottori prefecture, Japan, and to compare it with previous reports.

METHODS

All hip fractures in patients aged 35 years and older occurring between 2004 and 2006 were surveyed in all of the hospitals from the Tottori prefecture. The age- and gender-specific incidence rates were then calculated. Using these and previously reported data, the estimated number of hip fracture patients was determined using the age- and gender-specific incidence rates in each year from 1986 to 2006.

RESULTS

The survey identified 851, 906, and 1,059 patients aged 35 years and older, in 2004, 2005, and 2006 respectively. The residual lifetime risk of hip fracture for individuals at 50 years of age was estimated to be 5.6% for men and 20.0% for women. The estimated number of patients from 1986 to 2006 showed a significant increase over time for both genders.

CONCLUSIONS

The age- and gender-specific incidence of hip fracture in the Tottori prefecture, Japan has not plateaued for either gender.

Prevalence of adult-onset multifactorial disease among offspring of atomic bomb survivors

The first study to examine whether parental radiation exposure leads to increased heritable risk of common adult-onset multifactorial diseases (i.e., hypertension, diabetes mellitus, hypercholesterolemia, ischemic heart disease, and stroke) was conducted among 11,951 participants in the clinical examination program out of a potential of 24,673 mail survey subjects who were offspring of survivors born from May 1946 through December 1984. Logistic regression analyses demonstrated no evidence of an association between the prevalence of multifactorial diseases in the offspring and parental radiation exposure, after adjusting for age, city, gender and various risk factors. The odds ratio (OR) for a paternal dose of 1 Gy was 0.91 [95% confidence interval (CI) 0.81-1.01, P = 0.08], and that for a maternal dose of 1 Gy was 0.98 (95% CI 0.86-1.10, P = 0.71). There was no apparent effect of parental age at exposure or of elapsed time between parental exposure and birth, but male offspring had a low odds ratio (OR = 0.76 at 1 Gy) for paternal exposure, but cautious interpretation is needed for this finding. The clinical assessment of nearly 12,000 offspring of A-bomb survivors who have reached a median age of about 50 years provided no evidence for an increased prevalence of adult-onset multifactorial diseases in relation to parental radiation exposure.

[Surgical treatment for ischemic heart disease]

BACKGROUND

Surgical treatment for ischemic heart disease (IHD) has changed after the administration of off-pump coronary artery bypass grafting (CABG) [OPCAB] and left ventricular restoration (LVR). We studied the development of the treatment and the surgical results.

PATIENTS AND METHODS

Since May 2000 when the indication for OPCAB and LVR was defined, surgical treatment for IHD has been performed in 1,251 patients. The age ranged from 32 to 91 (mean 66 +/- 10) years and there were 977 men and 274 women. The elective operation was 1,130 and emergency 121. Definite indication for OPCAB was calcified ascending aorta, significant cerebrovascular disease, hemorrhagic tendency, and single vessel lesion. Conventional CABG (C-CAB) was the first choice and morbidity and surgical results were examined.

RESULTS

OPCAB was performed in 297 (29.9%) and combined operation with CABG was required in 258 patients (20.6%). In elective operation, hospital mortality was one in OPCAB and one in C-CAB. In OPCAB and C-CAB, stroke was none and one, and mediastinitis was 0 and 0, respectively.

CONCLUSION

The technique for OPCAB is necessary for CABG; however, it is not appropriate to persist with only OPCAB for CABG. Combined operation is often required with CABG and it is essential to perform precise C-CAB.

Significance of repeated resection for recurrent intrahepatic cholangiocarcinoma

BACKGROUND/AIMS

Management of patients with recurrent intrahepatic cholangiocarcinoma (ICC) following surgical resection is difficult, and surgical resection is rarely indicated. We retrospectively reviewed patients with recurrent intrahepatic cholangiocarcinoma.

METHODOLOGY

Between April 1998 and March 2007, 57 consecutive patients with ICC underwent surgical resection. Mode of recurrence and treatment of recurrent tumors, especially surgical resection for these tumors, in patients with cancer recurrence were evaluated.

RESULTS

37 (65%) patients experienced tumor recurrence. Out of these patients, 24 underwent some type of cancer-directed therapy, including 9 patients (24%) for whom surgical resection was attempted: the latter included 4 hepatic resections, 2 pulmonary resections, 2 tumor resections, and 1 gastric resection. For 6 patients with recurrent tumor in the liver or the lung, microscopic complete resection was achieved, while incomplete resection was resulted in the remaining 3 patients. No postoperative mortality was encountered. Among patients with complete resection, 3 are alive without disease 32, 39 and 77 months after the second operation, one has lived with disease for 13 months, and 2 died of disease after 22 and 26 months. No significant difference in overall survival was observed between patients undergoing primary and second surgical resections, calculated from the primary and the second operations, respectively.

CONCLUSIONS

Repeated surgical resection for recurrent ICC can be performed with acceptable morbidity, and affords selected patients a chance for long-term survival.

Neuromuscular synaptic function in mice lacking major subsets of gangliosides

Gangliosides are a family of sialylated glycosphingolipids enriched in the outer leaflet of neuronal membranes, in particular at synapses. Therefore, they have been hypothesized to play a functional role in synaptic transmission. We have measured in detail the electrophysiological parameters of synaptic transmission at the neuromuscular junction (NMJ) ex vivo of a GD3-synthase knockout mouse, expressing only the O- and a-series gangliosides, as well as of a GM2/GD2-synthase*GD3-synthase double-knockout (dKO) mouse, lacking all gangliosides except GM3. No major synaptic deficits were found in either null-mutant. However, some extra degree of rundown of acetylcholine release at high intensity use was present at the dKO NMJ and a temperature-specific increase in acetylcholine release at 35 degrees C was observed in GD3-synthase knockout NMJs, compared with wild-type. These results indicate that synaptic transmission at the NMJ is not crucially dependent on the particular presence of most ganglioside family members and remains largely intact in the sole presence of GM3 ganglioside. Rather, presynaptic gangliosides appear to play a modulating role in temperature- and use-dependent fine-tuning of transmitter output.

High expression of GADD-45alpha and VEGF induced tumor recurrence via upregulation of IL-2 after photodynamic therapy using NPe6

NPe6 is a novel second-generation photosensitizer used for photodynamic therapy (PDT). PDT using NPe6 and diode laser (664 nm) induces cell death, inflammatory reactions, immunological responses and damage to the microvasculature. In this study, we evaluated the influence of the immunological responses and of enhanced angiogenesis on the anti-tumor effect of NPe6-PDT using cytokine-overexpressing Lewis lung carcinoma (LLC), LLC-IL-2 cells both in vitro and in vivo. We showed by DNA microarray analysis in vitro that IL-2 and GADD-45alpha (growth arrest and DNA damage 45 alpha) mRNA expressions were induced by 3 h after NPe6-PDT applied at a dose killing 90% of the cells (LD90). IL-2-overexpressing cells (LLC/IL-2 cells) were resistant to the loss of clonogenicity as compared to the parental LLC cells in vitro. Furthermore, in female C57BL/6 mice, NPe6-PDT produced a cure rate of 66.7% in LLC tumors, whereas the cure rate was only 16.6% in LLC/IL-2 tumors, and overexpression of IL-2 caused failure of NPe6-PDT, with tumor recurrence, in vivo. These results suggest that IL-2 expression may play an unfavorable role in attenuation of the antitumor effect of NPe6-PDT. It has been reported that the expression of vascular endothelial growth factor (VEGF), in particular, may cause tumor recurrence after PDT and exert unfavorable effect in relation to attenuate the anti-tumor activity of PDT. Results of immunohistochemical analysis of LLC/IL-2 tumors have revealed that the expressions of GADD-45alpha and VEGF are induced in these tumors after PDT, and in particular, 12 h after PDT, the expression levels were much higher as compared with those in the LLC tumors. The results of our studies using in vitro and in vivo models suggest that the cell death caused by PDT was inhibited by induction of GADD-45alpha expression and that tumor recurrence was promoted by the enhancement of VEGF expression mediated by IL-2 upregulation. Therefore, it is speculated that the use of an IL-2 inhibitor may improve the efficacy of NPe6-PDT.