Have sperm counts deteriorated over the past 20 years in healthy, young Japanese men? Results from the Sapporo area

Changes in semen quality of healthy men is a controversial issue throughout the world. It is suspected that many chemical endocrine disrupters may affect the quality of semen. Although exposure to them may be extensive in Japan, no evidence of changes in semen quality has been reported. In this study, changes in semen volume and sperm counts were analyzed over 20 years in the Sapporo area of Japan. Semen volume and sperm counts were measured in 254 and 457 normal, healthy volunteers who lived in the Sapporo area in 1975-1980 and 1998, respectively. Posters and handbills were used to recruit participants in both studies. Semen samples were collected by masturbation after 3 days or more of abstinence. There was no change in semen volume between 1975-1980 and 1998. Mean sperm counts were 70.9 +/- 47.3 x 10(6)/mL in 1975-1980 and 79.6 +/- 49.3 x 10(6)/mL in 1998. Sperm counts did not decline over about 20 years. No significant correlation between age and sperm counts was recognized in either study. The rates of subjects with oligozoospermia and azoospermia were the same in both studies. In the 1975-1980 study, 34 of 254 (13.4%) participants had a child, and in the 1998 study, 51 of 457 (11.2%) participants had a child. Mean sperm count was significantly (P < .02) lower in the earlier study (66.0 +/- 44.9 x 106/mL) than in the 1998 study (98.7 +/- 60.2 x 10(6)/mL). This is the first reliable report in which changes in sperm counts in Japan were studied. We conclude that there was no evidence of deterioration in sperm counts of normal healthy men who lived in the Sapporo area of Japan over 20 years. However, selection bias in the recruitment of volunteers and the issue of variable abstinence might have affected the results of these studies. Therefore, well-designed prospective studies should be performed in several different regions to extrapolate our results on sperm counts to healthy, young Japanese men in general. Key words: Fertility, endocrine disruptors, seminalysis.     

Difference in sensitivity to vecuronium between patients with ocular and generalized myasthenia gravis

Patients with myasthenia gravis show sensitivity to non-depolarizing neuromuscular blocking drugs, but little is known about differences in this sensitivity between types of myasthenia. In 10 patients with ocular myasthenia gravis and 10 with generalized myasthenia gravis, twitch tension was monitored in the adductor pollicis muscle by supramaximal train-of-four stimulation of the ulnar nerve during anaesthesia with sevoflurane 2.5% and nitrous oxide 60%. After baseline measurement, an initial dose of vecuronium 10 microg kg(-1) was given. When the twitch height stabilized (maximum block after the first 10 microg kg(-1)), the next incremental dose of 10 microg kg(-1) was given and repeated until block, defined as [1-(first twitch/baseline first twitch)] x 100 reached 90%. Maximum block after the first dose of vecuronium in ocular patients was significantly less than that in generalized patients (median 51 vs 91%; P<0.05). Onset of block after the first dose of vecuronium was significantly slower in ocular than in generalized myasthenic patients (mean 300 vs 200 s; P<0.05). Doses required to attain a block of 90% or more were significantly higher in ocular than in generalized patients (median 20 vs 10 microg kg(-1); P<0.05). Clinicians should consider the type of disease according to the Osserman classification when using non-depolarizing neuromuscular. blocking drugs in patients with myasthenia gravis.     

Development of full-length Trk B-immunoreactive structures in the prefrontal and visual cortices of the macaque monkey

Distribution and morphological changes of cells containing the signal transducing neurotrophin receptor, full-length Trk B (fl-Trk B), were investigated in the prefrontal cortex (area FD) and the primary visual cortex (area OC) of the macaque monkey between embryonic day 140 and the adult stage. In area FD at the adult stage, fl-Trk B immunoreactivity was mainly observed in the pyramidal cells in layers II/III, V and VI. Small numbers of granule cells in layer IV were immunopositive. Bipolar and multipolar cells in layer II were rarely immunoreactive. At embryonic day 140, the number of fl-Trk B immunoreactive pyramidal cell was high, and gradually decreased until the adult stage. In layer IV, the number of fl-Trk B-ir cells was also high at embryonic day 140, and decreased remarkably from postnatal day 7 to the adult stage. On the other hand, in area OC at the adult stage, cells in layers II/III, IV, V and VI were fl-Trk B immunopositive. From embryonic day 140 until adulthood, the cells in layer IVc were fl-Trk B immunoreactive. The strongest fl-Trk B immunoreactivity in areas FD and OC occurred at postnatal month 6, coinciding with the time of the synapse overproduction. These findings suggest that ligands of fl-Trk B, such as BDNF and NT4/5 may be involved in the development and maintenance of the monkey cerebral cortices. Accepted: 26 July 1999     

Mediastinal cystic lesions: CT and MRI findings

In this article we describe various approaches to the evaluation of mediastinal cystic lesions using CT and MRI. Although cystic lesions generally appear to be uncomplicated and not difficult to diagnose, we consider that there are certain pitfalls in differentiating them from solid lesions. It is important to pay careful attention to the location (including ectopic occurrence), CT attenuation and/or MR intensity, thickness of the wall, tear-drop shape or alternation of shape owing to intrathoracic pressure, and pseudoenhancement. We suggest that MR be recommended when the findings of CT are equivocal, as they were in 32 of our cases.     

Concurrent chemoradiotherapy for locally unresectable head and neck cancer

In patients with locally unresectable head and neck cancer with large nodal involvement, the expected five-year survival is as low as 1-2%. To improve the prognosis of these patients, we studied the usefulness of concurrent chemoradiotherapy in a phase II trial. Between September 1996 and May 1999, thirty-five patients with locally unresectable head and neck cancer were administered concurrent chemoradiotherapy consisting of low-dose and long-term treatment with cisplatin (CDDP) plus 5-fluorouracil (5FU), or (L-CF); the L-CF regimen consisted of CDDP, 3 mg/m2 on 5 days of the week and 5FU, 150 mg/m2 as a 24-hour infusion on 5 days of the week. Concurrently, conventional radiotherapy was given up to total dose of around 60 Gy. In the 33 patients evaluable for response, 17 complete and 9 partial responses were noted, with an overall response rate of 79%. Oral mucostis and myelosuppression were the major side effects and mucositis was a dose limiting toxicity. This study demonstrates increase in survival among the responders (complete + partial) in the concurrent chemoradiotherapy setting. However 8 local relapses were eventually noted in the 17 complete responders. We concluded that this treatment strategy was beneficial in patients with locally unresectable head and neck cancer.     

Effect of bacterial metabolism in the intestine on colorectal tumors induced by 1,2-dimethylhydrazine in transgenic mice harboring human prototype c-Ha-ras genes

The number of colorectal tumors per mouse induced by 1,2-dimethylhydrazine in transgenic (Tg) mice carrying human c-Ha-ras genes was significantly reduced by ingestion of apple pectin (AP) or a culture condensate of Bifidobacterium longum(MB) compared with a control diet and non-Tg mice. However, there were no differences in the composition of fecal flora, water content, beta-glucuronidase and beta-glucosidase activities, and concentrations of organic acids and putrefactive products in the feces between the AP or MB diet and the control diet, or between the Tg mice and non-Tg mice. The concentration of secondary bile acids in the MB diet group was higher than that in the control group. These results suggested that there was no relationship between prevention of colorectal tumors in Tg mice and the AP or MB diet, or improvement of the intestinal environment due to these functional foods.     

Frequent alterations of the beta-catenin and TCF-4 genes, but not of the APC gene, in colon cancers with high-frequency microsatellite instability

High-frequency microsatellite instability (MSI-H) due to defective DNA mismatch repair (MMR) is a characteristic of the majority of tumors from kindreds with hereditary nonpolyposis colorectal cancer (HNPCC) and a subset of sporadic cancers. To better understand the molecular characteristics of colon cancers with MSI-H, we analyzed these cancers for alterations of genes, such as APC, beta-catenin, and TCF-4 genes, involved in the Wnt signaling pathway. Following the National Cancer Institute (NCI) criteria, 385 unselected colon cancers were classified as follows: 50 (13%) MSI-H tumors, 36 (9%) low-frequency MSI (MSI-L) tumors, and 299 (78%) microsatellite stable (MSS) tumors. The frequency of APC mutations was significantly lower in MSI-H tumors (9 out of 50) than in MSI-L (12 out of 20) and MSS (66 out of 100) tumors (P = 0.0005 and P < 0.0001, respectively). In contrast, the frequency of exon 3 mutations in the beta-catenin gene was higher in MSI-H tumors (10 out of 50) than in MSI-L tumors (0 out of 30; P = 0.0110) and MSS tumors (3 out of 100; P = 0.0010). Frameshift mutations in a (A)9 tract of the TCF-4 gene were detected in 44% (22 out of 50) of MSI-H tumors, but not in any of the 20 MSI-L tumors or 40 MSS tumors. In total, 78% of MSI-H tumors and 84% of the remaining tumors had at least one alteration in APC, beta-catenin, or the TCF-4 genes. Although further analysis is needed to functionally characterize the consequences of each of these alterations on beta-catenin/TCF target gene expression, our results suggest that the activation of the Wnt signaling pathway plays a pivotal role in colon tumorigenesis, irrespective of MSI status.     

Correlation between nuclear grade and biological prognostic variables in invasive Breast Cancer

BACKGROUND: Grading of carcinomas is an estimation of differentiation. Nuclear grading is the cytological evaluation of tumor nuclei in comparison with the nuclei of normal mammary epithelial cells. Because nuclear grading does not involve an assessment of the growth pattern of the tumor, it applies not only to invasive ductal carcinoma but also to other subtypes of breast carcinoma. METHODS: A total of 215 primary breast carcinomas obtained from the Affiliated Kihoku Hospital of Wakayama Medical College were enrolled in our present study. Nuclear grade was evaluated according to the criteria of the National Surgical Adjuvant Study of Breast Cancer (NSAS-B) protocol. Immunohistochemistry was also performed to determine Bcl-2, p53, c-erbB-2, estrogen receptor (ER) and MIB-1 expression in paraffin-embedded tissues for all cases. RESULTS: Thirty-two (14.9%) of the patients were graded as 1,124 (57.7%) as 2, and 59 (27.4%) as 3. Nuclear grade displayed a negative correlation with Bcl-2 expression (r=-0.308, p<0.0001), and a positive correlation with c-erbB-2 overexpression (r= 0.172, p=0.0117) and tumor proliferative index labeling by MIB-1 (r=0.485, p<0.0001). CONCLUSIONS: These results imply that nuclear grade is related to the characteristics of tumor biology, indicating that the morphology and biology of breast cancer are tightly linked. Our present results also suggest that adding the nuclear grade to the pathological diagnosis of invasive breast carcinoma may be clinically useful for predicting tumor behavior, for example aggressiveness, and for prognostication.     

Association of osteopontin with ischemic axonal death in periventricular leukomalacia

Osteopontin (OPN) is a bone matrix protein expressed my macrophages and related to the process of tissue calcification, and is also known to protect ischemic cells. To understand how OPN is involved in the process of ischemic axonal death in periventricular leukomalacia (PVL), we examined the immunoreactivity of OPN and ionized calcium binding adaptor molecule 1 (Iba1; microglia/ macrophage marker) at various stages of PVL. OPN immunoreactivity paralleled the number of Iba1-positive foam cells; a finding which suggests the production of OPN protein by foam cells. OPN immunoreactivity was not found in either normal white matter or acute PVL lesions, but was detected at the subacute and chronic stages in swollen and calcified axons bordering the ischemic zone. These findings suggest that OPN is closely associated with death of swollen axons at the periphery of the ischemic zone, regulating the presence or absence of calcification. Received: 20 January 1999 / Revised, accepted: 21 September 1999     

In vivo cisplatin resistance depending upon canalicular multispecific organic anion transporter (cMOAT).

The in vitro sensitivities to cisplatin of AH66 and AH66F cells, a variant obtained from AH66 cells, were very similar, when assayed in a medium containing 5% fetal bovine serum (FBS), whereas in the in vivo experiments AH66F cells were sensitive and AH66 cells were highly resistant to cisplatin. In this study, we examined the mechanism of the in vivo cisplatin resistance of AH66 cells. The in vitro cisplatin sensitivity of AH66 cells was lowered by changing FBS to 5% ascites fluid (ASF) in the assay medium and the sensitivity in FBS by treatment with buthioninesulfoximine (BSO). The sensitivity of AH66F cells was not changed by these treatments. Moreover, after culture in 5% ASF for 48 h, the accumulation of cisplatin in AH66 cells was decreased and the efflux of cisplatin from the cells was accelerated. The accumulation of cisplatin in AH66 cells in ASF was increased by pretreatment with BSO, sodium azide or probenecid. Then, we examined the expression of the glutathione (GSH) conjugate efflux pump family. Among them, only the expression of canalicular multispecific organic anion transporter (cMOAT) in AH66 cells was decreased by culture in FBS and enhanced by ASF. These results suggest that some substances contained in ASF enhanced the expression of cMOAT in the plasma membrane of AH66 cells and this transporter actively extruded cisplatin-GSH conjugate from the cells. Consequently, AH66 cells afford a cisplatin-resistant tumor in the host.