How do bioethics teachers in Japan cope with ethical disagreement among healthcare university students in the classroom? A survey on educators in charge

OBJECTIVE

The purpose of this study was to demonstrate how educators involved in the teaching of bioethics to healthcare university students in Japan would cope with ethical disagreement in the classroom, and to identify factors influencing them.

METHODS

A cross sectional survey was conducted using self administered questionnaires mailed to a sample of university faculty in charge of bioethics curriculum for university healthcare students.

RESULTS

A total of 107 usable questionnaires were returned: a response rate of 61.5%. When facing ethical disagreement in the classroom, coping behaviour differed depending on the topic of discussion, was influenced by educators' individual clear ethical attitudes regarding the topic of discussion, and was independent of many respondents' individual and social backgrounds. Among educators, it was commonly recognised that the purpose of bioethics education was to raise the level of awareness of ethical problems, to provide information about and knowledge of those issues, to raise students' sensitivity to ethical problems, and to teach students methods of reasoning and logical argument. Yet, despite this, several respondents considered the purpose of bioethics education to be to influence students about normative ethical judgments. There was no clear relationship, however, between ways of coping with ethical disagreement and educators' sense of the purpose of bioethics education.

CONCLUSIONS

This descriptive study suggests that educators involved in bioethics education for healthcare university students in Japan coped in various ways with ethical disagreement. Further research concerning ethical disagreement in educational settings is needed to provide better bioethics education for healthcare students.

Correlations between bone mineral density and demographic, lifestyle, and biochemical variables in community-dwelling Japanese women 69 years of age and over

INTRODUCTION

A few epidemiologic studies have comprehensively attempted to identify risk factors for low bone mineral density (BMD) in elderly Asian women. The purpose of this study was to identify demographic, lifestyle, and biochemical factors correlated with BMD in elderly Japanese women 69 years of age and over.

METHODS

The study design was cross-sectional. The subjects were 583 ambulatory women aged 69 years and over, and their average age was 74.3 (SD 4.4) years. Predictor variables were age, reproductive history, anthropometric indices, grip strength, calcium intake, lifestyle information, and serum 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D (1,25(OH)(2)D), osteocalcin (OC), and undercarboxylated osteocalcin (ucOC) values. The outcome variable was forearm BMD measured with a DTX-200 osteometer.

RESULTS

Simple linear regression analyses showed that BMD was significantly positively associated with body height, weight, body mass index, grip strength, serum albumin concentration, and "housework," and negatively associated with age, years since menopause, age at menarche, number of children, serum 1,25(OH)(2)D concentration, serum OC concentration, and ucOC concentration. The stepwise multiple regression analysis showed that weight (beta=0.00316, SE=0.00028, R(2)=0.180), age (beta=-0.00321, SE=0.00050, R(2)=0.108), log-transformed serum OC (beta=-0.0445, SE=0.0064, R(2)=0.053), log-transformed serum 1,25(OH)(2)D (beta=-0.0401, SE=0.0074, R(2)=0.050), "farmwork" (beta=0.00904, SE=0.00426, R(2)=0.005), and serum 25(OH)D concentration (beta=0.000281, SE=0.000120, R(2)=0.003) were significantly associated with BMD.

CONCLUSION

It was concluded that body weight is a major predictor of forearm BMD among the factors measured in this study in independent Japanese women 69 years of age and over and that serum 1,25(OH)(2)D concentration may be associated with cortical BMD. Maintenance of body weight is very important for maintaining BMD in this population, unless a large weight aggravates obesity-related diseases. A follow-up study is needed to confirm these findings.

Construction of unmodified oligonucleotide-based microarrays in the thermophilic cyanobacterium Thermosynechococcus elongatus BP-1: screening of the candidates for circadianly expressed genes

DNA microarrays with unmodified oligonucleotide probes are a cost-effective and high-performance alternative to cDNA microarrays. We searched every gene in the genome of the thermophilic cyanobacterium Thermosynechococcus elongatus BP-1 for 45-mer oligonucleotide probes with optimal nucleotide sequences, and found such probes in 90% of the genes. Using the probes, we constructed a microarray that represented 2,397 genes (95% of total genes). We detected only low signals in the negative control probes whose nucleotide sequences are not contained in the T. elongatus genome, demonstrating that specific hybridization occurred. To evaluate the reliability of the measurements obtained by the oligonucleotide microarray, we performed microarray experiments using RNA samples from two different time points of circadianly synchronized cultures, LL2 (early sub-jective day) and LL14 (early subjective night). Measurements obtained from the two independent microarray hybridizations were highly concordant (correlation coefficient [r] > 0.8). Northern blot analyses of 20 genes confirmed that expression changes detected by the microarrays were correct (r = 0.832). We identified 143 candidate clock-controlled genes whose expression levels at LL2 and LL14 were significantly different. Expression of 69 of them was enhanced at LL14 while expression of the other 74 was enhanced at LL2. The physiological functions of the genes were diverse and included metabolism, translation, transcription, membrane transport, DNA replication and repair, and cell growth and death.

Global analysis of circadian expression in the cyanobacterium Synechocystis sp. strain PCC 6803

Cyanobacteria are the only bacterial species found to have a circadian clock. We used DNA microarrays to examine circadian expression patterns in the cyanobacterium Synechocystis sp. strain PCC 6803. Our analysis identified 54 (2%) and 237 (9%) genes that exhibited circadian rhythms under stringent and relaxed filtering conditions, respectively. The expression of most cycling genes peaked around the time of transition from subjective day to night, suggesting that the main role of the circadian clock in Synechocystis is to adjust the physiological state of the cell to the upcoming night environment. There were several chromosomal regions where neighboring genes were expressed with similar circadian patterns. The physiological functions of the cycling genes were diverse and included a wide variety of metabolic pathways, membrane transport, and signal transduction. Genes involved in respiration and poly(3-hydroxyalkanoate) synthesis showed coordinated circadian expression, suggesting that the regulation is important for the supply of energy and carbon source in the night. Genes involved in transcription and translation also followed circadian cycling patterns. These genes may be important for output of the rhythmic information generated by the circadian clock. Our findings provided critical insights into the importance of the circadian clock on cellular physiology and the mechanism of clock-controlled gene regulation.

Roles of two ATPase-motif-containing domains in cyanobacterial circadian clock protein KaiC

Cyanobacterial clock protein KaiC has a hexagonal, pot-shaped structure composed of six identical dumbbell-shaped subunits. Each subunit has duplicated domains, and each domain has a set of ATPase motifs. The two spherical regions of the dumbbell are likely to correspond to two domains. We examined the role of the two sets of ATPase motifs by analyzing the in vitro activity of ATPgammaS binding, AMPPNP-induced hexamerization, thermostability, and phosphorylation of KaiC and by in vivo rhythm assays both in wild type KaiC (KaiCWT) and KaiCs carrying mutations in either Walker motif A or deduced catalytic Glu residues. We demonstrated that 1) the KaiC subunit had two types of ATP-binding sites, a high affinity site in N-terminal ATPase motifs and a low affinity site in C-terminal ATPase motifs, 2) the N-terminal motifs were responsible for hexamerization, and 3) the C-terminal motifs were responsible for both stabilization and phosphorylation of the KaiC hexamer. We proposed the following reaction mechanism. ATP preferentially binds to the N-terminal high affinity site, inducing the hexamerization of KaiC. Additional ATP then binds to the C-terminal low affinity site, stabilizing and phosphorylating the hexamer. We discussed the effect of these KaiC mutations on circadian bioluminescence rhythm in cells of cyanobacteria.

Response to preoperative chemotherapy affects prognosis in esophageal cancer

The effect of preoperative chemotherapy on prognosis is still controversial. We have investigated the relationship between responses to preoperative chemotherapy and prognosis after curative operations in patients with esophageal squamous cell carcinoma. Thirty-nine patients received preoperative chemotherapy with continuous infusion of 500 mg/m2 of 5-fluorouracil (5-FU) and intravenous injection of 20 mg/m2 of leucovorin every 12 hours for 5 days. On the 5th day alone, 70 mg/m2 of cisplatin was also infused. The effect was evaluated approximately 14 days after the end of one course of chemotherapy. The rates of responders and non-responders were 64.1% and 35.9%, respectively. After an interval of 21-28 days, transthoracic esophagectomy was performed. Significant histological effect by chemotherapy was found in responders compared to non-responders (P < 0.05). Responders had a significantly better prognosis than non-responders by Log-rank test (P < 0.01). This suggests that preoperative chemotherapy may contribute to better prognosis when the tumor is sensitive to chemotherapy.

Finite element analysis of the stresses around fixtures in various reconstructed mandibular models--part II (effect of horizontal load)

AIM OF EXPERIMENT: Having already studied the effect of vertical load (Nagasao et al., 2002), the purpose of this study was to investigate the effect of horizontal load on implants embedded into a virtually reconstructed mandible.

MATERIAL AND METHODS

Three-dimensional virtual models of various reconstructed mandibles were designed on a PC and 50 N horizontal loads were applied on the cantilever portion of the upper structure. Then, using a finite element analysis, stresses occurring around the implants were calculated, and the directions of the forces that cause the maximum von Mises stresses were evaluated. Finally, the results were compared with those from vertical loading.

RESULTS

In all models, the maximum stresses occurred around the implants embedded on the premolar region of the loaded side. In addition, the locations at which the maximum von Mises stresses occurred were greatly influenced by the structural character of the loaded side.

CONCLUSION

When horizontal loads were applied to reconstructed mandibles, the location and direction of the maximum stresses around the dental implants appeared to be influenced much more by the structural characters of the reconstructed mandibles when compared with vertical loads.

Effectiveness of preoperative chemotherapy using carboplatin (CBDCA) and surgery against an esophageal small cell carcinoma

A 63-year-old man presented to our hospital with persistent dysphagia. Radiologic and endoscopic examination disclosed a 2.0-cm exophytic tumor in the middle third of the esophagus. An endscopically obtained biopsy specimen was found to represent undifferentiated small cell carcinoma. Computed tomography of the chest, abdomen, and cervical region was performed, as were gallium and bone scintigraphy. Metastasis to an adjacent lymph node was detected, without metastasis to distant organs. After neoadjuvant chemotherapy with carboplatin (CBDCA) (400 mg/m2) and etoposide (VP-16) (100 mg/m2), endoscopy and barium-swallow esophagography showed regression. Thoracic esophagectomy then was performed with mediastinal, abdominal and cervical lymph node dissection. The resected tumor was polypoid, measuring 0.5 x 0.5 cm. The lesion consisted mainly of small anaplastic cells, but included a small focus of squamous cell carcinoma. The patient has survived for more than 7 months with no further treatment and no evidence of recurrent disease.

Effects of preoperative chemotherapy on metastatic lymph nodes in esophageal squamous cell carcinoma

The aim of this study was to evaluate the effect of preoperative chemotherapy on metastatic lymph nodes and on the outcome of patients who underwent esophagectomy for advanced squamous cell carcinoma of the esophagus. Fifty-nine patients with potentially resectable squamous cell carcinoma of the esophagus were studied. Twenty patients (group A) were treated by preoperative chemotherapy with cisplatin, 5-fluorouracil, and leucovorin, followed by surgery. Thirty-nine patients underwent surgery alone (group B). A total of 2591 resected lymph nodes were histologically evaluated for metastasis and the effect of chemotherapy. The metastasis rate in the resected lymph nodes, the number of metastatic lymph nodes, and outcome of the patients were statistically analyzed between groups. In group A, the clinical and pathological response rates were 75% and 75% respectively. The metastasis rate in the resected lymph nodes was significantly higher in group B (P < 0.01). The mean number of metastatic lymph nodes was significantly lower in group A (P < 0.05). Furthermore, the mean number of metastatic lymph nodes was significantly lower in the chemotherapy responders than in non-responders. The survival rate in group A was better than in group B (P = 0.07). Preoperative chemotherapy reduced the number of metastatic lymph nodes and may contribute to improving the outcome of the patients who have undergone esophagectomy for squamous cell carcinoma of the esophagus.

Low vertebral cancellous bone density in peripubertal girls with Turner's syndrome and boys with hypogonadism

OBJECTIVE

To characterize the changes of vertebral cancellous bone density in children with hypogonadism.

STUDY DESIGN

Quantitative computed tomography (QCT) values of vertebral cancellous bone in 21 girls with Turner's syndrome, 12 boys with hypogonadism, and 46 age-matched controls (24 boys, 22 girls) were studied. The subjects were divided into the following subgroups by the age (year) at the time of the measurement: A. 4-6.9; B. 7-9.9; C. 10-12.9.

RESULTS

QCT values for Turner's syndrome vs control girls in the same age groups (A, B, and C) were (mean +/- SD) 226 +/- 36 vs 216 +/- 31 (NS), 193 +/- 29 vs 220 +/- 33 (NS), and 177 +/- 32 vs 217 +/- 17 (p < 0.01) mg/cm3, respectively. Those for boys with hypogonadism vs control boys (A, B, and C) were 236 +/- 15 vs 240 +/- 12 (NS), 187 +/- 21 vs 225 +/- 28 (p < 0.05), and 172 +/- 11 vs 216 +/- 26 (p < 0.0001) mg/cm, respectively. The cross-sectional data for Turner's syndrome and boys with hypogonadism had significant negative correlation with chronological age (r = 0.59; p < 0.001).

CONCLUSION

These results showed that vertebral cancellous bone density in children with hypogonadism began to decrease during the peripubertal period in contrast to the constant values in controls, suggesting that a small amount of gonadal steroid in healthy children has an important role in maintaining normal bone density.

Finite element analysis of the stresses around endosseous implants in various reconstructed mandibular models

PURPOSE

To calculate the location and intensity of the maximum stresses occurring around implants in the reconstructed mandible.

MATERIAL AND METHODS

Human preserved mandibles and fibulae were used to design 3-D mandibular models on a Desktop Computer. Various 3-D simulation models representing mandibles were made. Implants (fixtures) and superstructures were then embedded in each model and occlusal pressure was applied to the cantilever portion of the superstructure. Von Mises stress, the maximum and minimum principal stress on each model were calculated using finite element structural analysis software. Finally, evaluation of the stresses around each fixture hole was performed.

RESULTS

It appeared that for each fixture hole, the direction and the magnitude of the stresses were influenced by complex factors such as the thickness of the cortical bone where the fixtures were embedded, the degree of vertical displacement under load, and the relationship between adjacent fixtures.

CONCLUSION

Location and intensity of the stresses occurring around fixtures differs significantly between various types of mandibular reconstruction. Published by Elsevier Science Ltd.

Genetic polymorphisms of cytochrome P450 1A1 and risk of gallbladder cancer

The relation between cytochrome P4501A1 (CYP1A1) gene polymorphisms and the risk of gallbladder cancer was examined. To clarify individual differences in susceptibility to gallbladder carcinogenesis, we investigated the frequency of the Mspl and Ile-Val polymorphisms of the CYP1A1 gene, in 52 patients with gallbladder cancer (32 females, 20 males) and 104 healthy controls (64 females, 40 males). We then examined the relationship between the CYP1A1 polymorphisms and the development of gallbladder cancer in members of both sexes. A statistical difference in the frequencies of the MspI and Ile-Val polymorphisms or their alleles (ml, m2 and Ile, Val) was not observed in the male patients and controls. Among females, however, the frequencies of genotypes C and Ile/Val were significantly higher (p < 0.05) in the patients than in their controls. Moreover, the frequency of the hetero genotype Ile/Val was statistically higher (p < 0.05) in the female patients than in the male patients. This study demonstrated a significant over-representation of genotypes C and Ile/Val in female patients with gallbladder cancer. Females with genotypes C and/or Ile/Val may have a high genetic susceptibility to the development of gallbladder cancer.

Multiframe observation of an intense femtosecond optical pulse propagating in air

We have demonstrated femtosecond time-resolved and picosecond time-interval successive observations of a single femtosecond optical pulse propagating in air with ultrafast self-modulation such as filamentation. A quadruple femtosecond probe pulse crossing an intense propagating pulse at picosecond intervals was able to capture directly four successive images of the propagating pulse as in a movie but with femtosecond time resolution. From this observation, we can directly analyze and recognize the propagation process, which is significantly affected by pulse-energy fluctuation, and (or) atmospheric turbulence from shot to shot.

Three-dimensional imaging of a tissuelike phantom by diffusion optical tomography

Three-dimensional imaging of three small absorbers embedded in a tissuelike cylindrical solid phantom was conducted by diffusion optical tomography. Each absorber, which was 10 mm in diameter and 10 mm high, was located on the same plane in a phantom, which was 80 mm in diameter and 140 mm high. The optical properties of the phantom were similar to those of the human breast; that is, one absorber had lower absorption and the other two absorbers had higher absorption than that of the phantom. Reemission from the phantom was measured with a multichannel photon counting system. Image reconstruction was performed by our average value method. We were able to distinguish lower and higher absorbers quantitatively. This result shows that our method can diagnose not only the existence of but also a morbid state of breast cancer.

Intrahepatic cholangiojejunostomy for unresectable malignant biliary tumors with obstructive jaundice

We reviewed our experience with intrahepatic cholangiojejunostomy as a palliative therapy for patients with unresectable malignant diseases involving the ductal confluence or the common hepatic duct. Fifteen patients with malignant biliary obstruction were treated by cholangiojejunostomy at our hospital. Two patients had intrahepatic cholangiocarcinoma, 7 had gallbladder carcinoma, 5 had bile duct carcionoma, and 1 had pancreatic carcinoma. Segment III cholangiojejunostomies were performed in 14 patients and segment V cholangiojejunostomy in 1. Contraindications for surgical resection were locoregional invasion of tumors involving the proper and/or common hepatic artery and portal vein in 15 patients and the presence of hepatic metastases in 6 patients. Liver metastases were detected in 5 of the 7 patients with gallbladder carcinoma. Postoperative complications occurred in 2 patients (13%), but there was no leakage of the cholangioenteric anastomosis in our series. There was no operative mortality after cholangiojejunostomy. Of the 9 patients who survived for more than 6 months after surgery, 7 showed a significant improvement in performance status (PS) (82 +/- 10%) 3 months after the surgery compared with the preoperative PS (70 +/- 7%). Four of the 9 patients had recurrent cholangitis as a late complication, but 4 were completely free from jaundice. Median survival after cholangioenteric bypass was 9 months (range, 2-25 months). With respect to tumor location, the median survival time was 4 months (range, 2-25 months) in patients with gallbladder carcinoma and 15.5 months (range, 12-22 months) in those with bile duct carcinoma. While the median survival period after surgery was only 3 months (range, 2 to 8 months) in the 5 patients with hepatic metastases from gallbladder carcinoma, 2 patients without liver metastasis survived for 9 and 25 months after segment III cholangioenteric bypass. In conclusion, cholangiojejunostomy can provide useful palliation for malignant biliary obstruction when combined with careful patient selection.

Response of renal sympathetic nerve activity to parabolic flight-induced gravitational change in conscious rats

The renal sympathetic nerve activity (RNA) response to gravitational changes induced by parabolic flight was examined in chronically instrumented conscious rats. Two types of RNA responses were found. In six out of 12 rats, the RNA did not respond during the 2 G period, but immediately fell to background levels on entry into microgravity (microG), then recovered to the 1 G control level during continued microG (shutdown obvious group). In the other six rats, the RNA increased to 158+/-13% at the end of the 2 G period, increased further to 195+/-22% on entry into microG, then gradually recovered to that seen at 1 G (shutdown obscure group). The mean arterial pressure in the shutdown obvious group was significantly higher and the heart rate tended to be higher than in the shutdown obscure group, suggesting that the baseline sympathetic tone in the shutdown obvious group was higher than in the shutdown obscure group. These results suggest that the RNA response to parabolic flight might be affected by the baseline sympathetic tone.

Characterization of a membrane-bound arginine-specific serine protease from rat intestinal mucosa

Previously we isolated and characterized a membrane-bound, arginine-specific serine protease from pig intestinal mucosa [J. Biol. Chem. 269, 32985-32991 (1994)]. For further characterization of this type of enzyme, we cloned a cDNA from rat intestinal mucosa encoding the precursor of a similar protease. The partial amino acid sequences determined for the pig enzyme were found to be shared almost completely by the rat enzyme. The serine protease domain of the rat enzyme, heterologously expressed in Escherichia coli, specifically cleaved Arg (or Lys)-X bonds with a marked preference for Arg-Arg or Arg-Lys, similar to the pig enzyme. The mRNA for the rat enzyme was shown to be distributed mainly in intestine, and the enzyme was detected in the duodenal mucosa as a 70 kDa protein. Immunohistochemical analysis of the small intestinal tissue showed that the enzyme is localized mainly on brushborder membranes.

Vitamin D insufficiency in Japanese female college students: a preliminary report

Vitamin D insufficiency, a risk factor for osteoporosis, has been well investigated in elderly women worldwide, but little information has been available for younger women. This study aimed to determine serum 25-hydroxyvitamin D [25(OH)D] levels in Japanese female college students, and to test whether there is an association between 25(OH)D and bone strength. Subjects were 77 Japanese female junior college students aged 19-24 years. Serum 25(OH)D was measured with high performance liquid chromatography. Bone strength of the calcaneus was evaluated using the osteo sono-assessment index (OSI), a combined index reflecting the bone mass, bone architecture, and elasticity, as measured by quantitative ultrasound densitometry (AOS-100, Aloka). The mean 25(OH)D concentration was 34.2 nmol/L (SD +/- 12.1). The proportion of subjects with 25(OH)D less than 30 nmol/L, a cut-off value for vitamin D insufficiency, was 31/77 (40.3%). Simple linear regression analysis showed that there was a significant linear relationship between 25(OH)D and OSI (R2 = 0.098, p = 0.0069). The association held even after adjusting for weight (partial R2 = 0.098, p = 0.0023). Body weight was also a significant predictor of OSI (partial R2 = 0.105, p = 0.0034). These results suggest that vitamin D insufficiency may be prevalent in healthy young women. Moreover, low levels of 25(OH)D in young women may adversely affect bone strength. An additional, newly designed epidemiological study with a sufficient sample size is needed to confirm the present findings.

The effect of cAMP on electrogenic Na(+) absorption in the rat distal colon

Cyclic AMP is a ubiquitous second messenger produced in cells in response to extracellular stimulants. The aim of this study was to examine its role in the regulation of amiloride-sensitive electrogenic Na(+) absorption in the rat distal colon by measuring the short-circuit current (I(sc)) and (22)Na(+) fluxes in a chamber-mounted mucosal sheet. Forskolin stimulated the amiloride-inhibitable I(sc) and amiloride-inhibitable (22)Na(+) absorption. 8Br-cAMP also stimulated the amiloride-inhibitable I(sc). Furthermore, isoproterenol, acting via beta-adrenergic activation, stimulated the amiloride-inhibitable I(sc). The isoproterenol-induced increase in the amiloride-sensitive I(sc) was largely suppressed by H89, a protein kinase A inhibitor. In conclusion, cAMP can upregulate amiloride-sensitive electrogenic Na(+) absorption in the rat distal colon.

Photon path distribution and optical responses of turbid media: theoretical analysis based on the microscopic Beer-Lambert law

A concise theoretical treatment has been developed to describe the optical responses of a highly scattering inhomogeneous medium using functions of the photon path distribution (PPD). The treatment is based on the microscopic Beer-Lambert law and has been found to yield a complete set of optical responses by time- and frequency-domain measurements. The PPD is defined for possible photons having a total zigzag pathlength of l between the points of light input and detection. Such a distribution is independent of the absorption properties of the medium and can be uniquely determined for the medium under quantification. Therefore, the PPD can be calculated with an imaginary reference medium having the same optical properties as the medium under quantification except for the absence of absorption. One of the advantages of this method is that the optical responses, the total attenuation, the mean pathlength, etc are expressed by functions of the PPD and the absorption distribution.