Professional dental care provision systems for persons with disabilities by prefecture in Japan

OBJECTIVE

The number of persons with disabilities has increased and aged. Although it is important to maintain good oral health to extend healthy life expectancy, it is difficult for such people. This study aimed to analyze regional disparities in dental care provision systems for disabled people and to propose measures for the establishment of an appropriate system.

BASIC RESEARCH DESIGN

To examine regional disparities in dental care provision systems for persons with disabilities, the number of practicing dentists and dental clinics per 100,000 population, dentists certified by the Japanese Society for Disability and Oral Health, and institutions with certified dentists per 100,000 disabled persons for each prefecture were calculated. The Gini coefficient of each was also calculated to visualize and analyze regional disparities.

RESULT

The Gini coefficients were 0.09 and 0.07 for practicing dentists and dental clinics and 0.32 and 0.28 for the certified dentists and institutions with the certified dentists, respectively. Dental institutions for the disabled abounded in the three metropolitan areas: Tokyo, Aichi, and Osaka, and their density tended to be lower in northern and southern Japan. In prefectures with few such institutions, there was no correlation between the number of institutions and prefectural residents' income, and some prefectures had similar incomes but had many institutions.

CONCLUSION

The distribution of dental care to the disabled is highly uneven in Japan, therefore, a system needs to be established to address this issue.

Changes in nutritional status by recovery phase interventions would be a powerful determinant of cardiovascular prognosis in heart failure patients

Background

Adequate nutrition has been proposed for better cardiovascular prognosis as well as fitness, although the impact of the “changes” in nutrition and fitness at recovery phase on the future prognosis has been unclear.

Purpose

We aimed to examine whether the change in nutritional level as a result of dietary intervention combined with exercise would determine patients' cardiovascular prognosis.

Methods

This study involved 398 consecutive patients who participated in phase II comprehensive cardiac rehabilitation (CCR) for at least three months. All patients underwent cardiopulmonary exercise test (CPX) at the initial and completion periods of CCR. Individual dietary guidance was periodically performed with exercise. Peak oxygen uptake (PVO2) was measured through CPX to evaluate the fitness level, whereas nutritional status was evaluated using the geriatric nutritional risk index (GNRI). Patients were divided in two groups according to the baseline GNRI and the change in GNRI (ΔGNRI) by the median, respectively, to compare their prognosis between groups. Then they were classified into four categories according to the median values of the changes in GNRI (ΔGNRI) and PVO2 (ΔPVO2) during CCR: “Both improved”, “Only GNRI improved”, “Only PVO2 improved” and “Both NOT improved”, to compare MACCE-free rate between categories.

Results

The rate of MACCE showed significant difference between categories (14%, 18%, 19% and 36%, p<0.001), which was approximately 2 times higher in “Both NOT improved” than the others. Kaplan-Meier analysis showed that according to the level of ΔGNRI, “higher ΔGNRI group” showed significantly higher in MACCE-free survival rate than “lower ΔGNRI group” (log rank p=0.010), whereas there was no significant difference according to the baseline GNRI (see figure). According to the categories divided by ΔGNRI and ΔPVO2, MACCE-free rate was significantly lower in “Both NOT improved” (log rank p<0.001) compared to the other categories. Cox proportional hazard regression analysis revealed that “both NOT improved” was an independent predictor of MACCE (hazard ratio, 2.1, 95% confident interval, 1.344–3.175, p<0.001).

Conclusion

Changes in nutritional level would determine patients' cardiovascular prognosis rather than the baseline nutritional level. Non-responders who showed no improvement in nutritional or fitness by interventions may result in a poor cardiovascular outcome.

Funding Acknowledgement

Type of funding source: None

Geographic distribution of dental specialists permitted to advertise dental practices in Japan

OBJECTIVE

The purpose of this study was to determine the geographic distribution of dental specialists permitted to advertise dental practices in Japan.

METHOD

We identified the populations of 349 secondary medical zones nationwide from the 2015 population census, as well as the number of dentists in five specialties, namely oral surgeons, pedodontists, periodontists, dental anesthesiologists, and dental radiologists, who had been permitted to advertise dental practices, from a 2016 survey of physicians, dentists, and pharmacists. We determined the placement rate, Lorenz curve, and Gini coefficient for dentists in each specialty in order to describe their geographic distributions.

RESULTS

The placement rates of at least one of these types of dentist in each secondary medical zone were 73.9% for oral surgeons, 66.2% for pedodontists, 60.5% for periodontists, 31.8% for dental anesthesiologists, and 18.3% for dental radiologists. The Gini coefficients were 0.397, 0.400, 0.491, 0.650, and 0.761, respectively.

CONCLUSION

The dentists in each specialty were few in number and were unequally distributed among the zones, but less so for oral surgeons and pedodontists. Dental anesthesiologists and radiologists were located primarily at university hospitals in urban areas and, therefore, were more unequally distributed.

Does mandatory postgraduate clinical training worsen geographic distribution of dentists in Japan?

Postgraduate clinical training for dentists has been mandatory in Japan since 2006. Hirata et al. reported that the geographic distribution of postgraduate dental trainees by prefecture in 2006 was worse than that of practicing dentists. This suggests that the postgraduate clinical training system could intensify the problem of distribution of dentists. In this study, therefore, we reviewed the geographic distribution of postgraduate dental trainees and practicing dentists between 2006 and 2010 in detail by city, ward, town and village by using the Lorenz curve and Gini coefficient. The results showed that while there was no significant worsening of geographic distribution of postgraduate dental trainees, the distribution of practicing dentists continued to deteriorate. A number of reasons may explain these findings: the clinical training system is based on a one-year employment contract, and dentists subsequently relocate as driven by the market; and geographic distribution among cities, towns and villages has worsened as a result of the merger of municipalities. The geographic distribution of practicing dentists is expected to deteriorate further if the number of dentists takes a downward turn in the future. Therefore, it is necessary to continuously review the distribution of postgraduate dental trainees.

Trends in percentage of postgraduate dental trainees at dental clinics

A facilities-group system designed to provide clinical training at dental clinics was developed after postgraduate clinical training became mandatory for dentists in Japan in 2006. As a result, there has been a steady increase in the number of dental clinics collaborating with dental school hospitals under this program. A larger number of dental clinics have also been designated as single-system facilities, program management facilities or collaborating facilities. However, it remains to be determined whether this increase in the number of dental clinics designated as clinical training facilities has led to an increase in the amount of training offered. Therefore, the purpose of this study was to investigate trends in the percentage of postgraduate dental trainees at dental clinics between fiscal years 2006 and 2010. The results showed no significant correlation among (1) the percentage of dental clinics designated as single-system collaborating facilities, (2) the percentage of training programs at dental clinics, and (3) the proportion of training program recruitment offers by dental clinics compared to the total number of recruits. These findings showed that increasing the number of collaborating dental clinics did not lead to an increase in the amount of clinical training at dental clinics. The findings also suggest that increasing the number of single-system or program management dental clinics is important in promoting clinical training at dental clinics.

3D niche microarrays for systems-level analyses of cell fate

The behaviour of mammalian cells in a tissue is governed by the three-dimensional (3D) microenvironment and involves a dynamic interplay between biochemical and mechanical signals provided by the extracellular matrix (ECM), cell-cell interactions and soluble factors. The complexity of the microenvironment and the context-dependent cell responses that arise from these interactions have posed a major challenge to understanding the underlying regulatory mechanisms. Here we develop an experimental paradigm to dissect the role of various interacting factors by simultaneously synthesizing more than 1,000 unique microenvironments with robotic nanolitre liquid-dispensing technology and by probing their effects on cell fate. Using this novel 3D microarray platform, we assess the combined effects of matrix elasticity, proteolytic degradability and three distinct classes of signalling proteins on mouse embryonic stem cells, unveiling a comprehensive map of interactions involved in regulating self-renewal. This approach is broadly applicable to gain a systems-level understanding of multifactorial 3D cell-matrix interactions.

Trends in the geographic distribution of dental clinics in Japan

AIM

In Japan, along with the increase in the number of dentists, the number of dental facilities has continuously increased as well. This study aimed to examine whether the increase in the number of dental clinics in Japan has led to an improvement in their geographic distribution.

METHODS

We analysed the number of dental clinics and population in all municipalities in Japan as of 2000, 2005 and 2010. We obtained data on the population from the population census and data on the number of dental clinics from the Survey of Medical Institutions. The number of municipalities was 3,258 in 2000 but had dropped to 1,750 by 2010 due to municipal mergers so population and dental data for other years were recalculated based on 2010 municipal boundaries. Lorenz curves and Gini coefficients were used to assess the distribution of dental clinics per 100,000 persons.

RESULTS

The mean number of dental clinics per 100,000 persons among all municipalities was 49.9 in 2000, 52.2 in 2005 and 53.4 in 2010. The Gini coefficient for the clinics in the whole country was 0.172 in 2000, 0.164 in 2005 and 0.153 in 2010.

CONCLUSION

The results suggest that the regional inequalities in the availability of dentists have been reduced gradually as the number of dental clinics has increased.

Lymphatic architecture of the human gingival interdental papilla

Many studies have investigated the lymphatic architecture of head and neck using experimental animals, confirming the existence of lymphatic networks beneath the epithelium in gingival tissue. In this study, we investigated the use of these lymphatics as a drug delivery route by studying the architecture of lymphatic vessels in human interdental papilla. Serial cryosections were cut using the film-transfer method. To identify lymphatics, the sections were stained using enzyme histochemical and immunohistochemical techniques and three-dimensional images of lymphatics were reconstructed using 3D visualization software. Capillary lymphatic networks were observed in the lamina propria beneath the epithelium in human interdental papilla, and they joined with lymphatic networks beneath the epithelium in free gingiva. The networks consisted of a single layer of large irregular, hexagonal meshes and precollecting lymphatic vessels heading toward collecting lymphatic vessels that exited on the periosteum of the alveolar crest. These findings suggest that lymphatic flow from the interdental papilla drains into collecting lymphatic vessels running buccolingually on the alveolar crest of the interdental papilla. This may be an important anatomical feature during inflammation throughout the oral cavity in that the drainage function is maintained by part of lymphatic flow that is not impaired during the healing process.

Geographic distribution of dentists in Japan: 1980-2000

OBJECTIVE

In the late 1950s and 1960s, Japan recognized that it had a shortage of dentists and that they were unevenly distributed. To solve these problems, four national and eight private dental schools were established, leading to a significant increase in the number of dental students in the 1970s and 1980s. The purpose of this study was to investigate the effects of this increased supply on the geographic distribution of dentists in Japan.

METHOD

We determined the number of dentists and the population in each of Japan's 3252 municipalities. The ratio of the number of dentists to the population of an area was assessed using Gini coefficients calculated from Lorenz curves.

RESULTS

From 1980 to 2000, the average number of dentists per 100,000 persons in Japan increased from 44 to 70. The Lorenz curve plotted for 1980-1990 appeared as a nearly diagonal line, with the Gini coefficient decreasing from 0.310 to 0.263. The Gini coefficient in the year 2000 was 0.255, indicating only a slight improvement in 10 years from 1990 to 2000.

CONCLUSIONS

The results suggest that the geographical distribution of dentists in Japan is influenced by municipalities' population size. While the number of dentists in municipalities with populations of less than 5000 increased during the years from 1980 to 2000, 25.9 percent of these municipalities still had no dentists at the end of this period. This is an important issue that warrants prompt corrective action.

Dental erosion and sulfuric ion exposure levels in individuals working with sulfuric acid in lead storage battery manufacturing plant measured with mouth-rinse index

To investigate dental erosion in employees working with sulfuric acid at a lead storage battery manufacturing plant and level of personal exposure to sulfuric ions, we measured sulfuric ion concentrations in the mouth rinse of those employees. We also measured exposure levels from air samples obtained from 2 employees from the same plant who did not work with sulfuric acid using a portable air sampler. At the same time, we collected and compared their mouth rinses with those from other employees. More specifically, we measured and compared sulfuric ion, calcium, and magnesium concentrations, along with pH levels from the mouth rinse of these two groups. Positive correlations were found between sulfuric ion and calcium concentrations (r=0.61, p<0.005), calcium and magnesium concentrations (r=0.61, p<0.005), Ca/Mg and calcium concentrations (r=0.64, p<0.005), and sulfuric ion and magnesium concentrations (r=0.55, p<0.005). Negative correlations were found between sulfuric ion concentrations and pH levels (r=-0.31, p<0.01), and magnesium concentrations and pH levels (r=-0.32, p<0.01). This suggests that mouth rinse from employees working with sulfuric acid could function as an indicator of sulfuric ion concentration in the work environment. Furthermore, this could lead to the development of a more accurate indicator of individual exposure.

AT7519, A novel small molecule multi-cyclin-dependent kinase inhibitor, induces apoptosis in multiple myeloma via GSK-3beta activation and RNA polymerase II inhibition

Dysregulated cell cycling is a universal hallmark of cancer and is often mediated by abnormal activation of cyclin-dependent kinases (CDKs) and their cyclin partners. Overexpression of individual complexes are reported in multiple myeloma (MM), making them attractive therapeutic targets. In this study, we investigate the preclinical activity of a novel small-molecule multi-CDK inhibitor, AT7519, in MM. We show the anti-MM activity of AT7519 displaying potent cytotoxicity and apoptosis; associated with in vivo tumor growth inhibition and prolonged survival. At the molecular level, AT7519 inhibited RNA polymerase II (RNA pol II) phosphorylation, a CDK9, 7 substrate, associated with decreased RNA synthesis confirmed by [(3)H] Uridine incorporation. In addition, AT7519 inhibited glycogen synthase kinase 3beta (GSK-3beta) phosphorylation; conversely pretreatment with a selective GSK-3 inhibitor and shRNA GSK-3beta knockdown restored MM survival, suggesting the involvement of GSK-3beta in AT7519-induced apoptosis. GSK-3beta activation was independent of RNA pol II dephosphorylation confirmed by alpha-amanitin, a specific RNA pol II inihibitor, showing potent inhibition of RNA pol II phosphorylation without corresponding effects on GSK-3beta phosphorylation. These results offer new insights into the crucial, yet controversial role of GSK-3beta in MM and show significant anti-MM activity of AT7519, providing the rationale for its clinical evaluation in MM.

Effect of the specific P53 stabilizer CBS9106 on multiple myeloma (MM)

8601

Background: The mutations of P53 tumor suppressor protein are associated with progressive in Multiple Myeloma (MM), conversely, stabilization of P53 leads to cell cycle arrest and apoptosis. In this study, we examined p53 protein expression and demonstrated the effect of P53 stabilization using a novel specific P53 stabilizer CBS9106 in MM. Method: We examined P53 protein expression using Immunoblot analysis, as well as the growth inhibitory effect of CBS9106 in MM cell lines and primary tumor cells from MM patients. We also defined whether CBS9106 can overcome the growth promoting effect of exogenous cytokines and bone marrow stroma cells (BMSCs) using [3H]-thymidine uptake assay. Results: Expression of P53 protein was observed in 3/3 primary tumor cells from MM patients and 6/6 MM cell lines. CBS9106 at low nM levels triggered cytotoxicity against p53 wild type MM cell lines and primary tumor cells from MM patients, associated with phosphorylation of P53 (serine15 and 20). In contrast, CBS9106 did not affect the survival of normal peripheral blood mononuclear cells from healthy volunteers at concentrations as high as 10 μM. This agent also induced G1 cell cycle arrest, followed by apoptosis associated with cleavage of caspase-3, -8, -9 and PARP. Neither growth stimulating cytokines (IL-6 and IGF-1) nor BMSCs protected against apoptotic effect of CBS9106. Moreover, we demonstrate that combination of CBS9106 with MDM2 inhibitor Nutrin3 or proteasome inhibitor bortezomib induces synergistic anti-MM activity in both P53 wild type MM cell lines and primary tumor cells from MM patients. Conclusions: Stabilizing P53 by CBS9106 represents a novel promising p53-based therapy in MM. These results provide the preclinical framework supporting evaluation of CBS9106 in clinical trials to improve patient outcome in MM.

No significant financial relationships to disclose.

Ascorbic acid inhibits antitumor activity of bortezomib in vivo

Earlier studies have shown that ascorbic acid (vitamin C) inhibits bortezomib-induced cytotoxicity against cancer cells in vitro. However, the clinical significance of vitamin C on bortezomib treatment is unclear. In this study, we examined whether daily oral intake of vitamin C inhibits antimultiple myeloma (MM) activities of bortezomib. Vitamin C, at orally achievable concentrations, inhibited in vitro MM cell cytotoxicity of bortezomib and blocked its inhibitory effect on 20S proteasome activity. Specifically, plasma collected from healthy volunteers taking 1 g/day vitamin C reduced bortezomib-induced MM cell death in vitro. This antagonistic effect of vitamin C against proteasome inhibitors is limited to the boronate class of inhibitors (bortezomib and MG262). In vivo activity of this combination treatment was then evaluated using our xenograft model of human MM in SCID (severe combined immune-deficient) mice. Bortezomib (0.1 mg/kg twice a week for 4 weeks) significantly inhibits in vivo MM cell growth, which was blocked by oral vitamin C (40 mg/kg/day). Therefore, our results for the first time show that vitamin C can significantly reduce the activity of bortezomib treatment in vivo; and importantly, suggest that patients receiving treatment with bortezomib should avoid taking vitamin C dietary supplements.

[Coronary artery bypass in octogenarians; how to reduce operative mortality and enhance long-term quality of life]

Octogenarians are at increased risk for perioperative morbidity and mortality after coronary artery bypass. This study is aimed to elucidate the suitable operative strategy and perioperative management. A retrospective analysis was conducted of 54 consecutive patients with 80-years of age or older, who underwent elective isolated coronary artery bypass between May 1999 and May 2008. Mean follow-up was 43.3 months and 96.3% complete. Operavive mortality was 3.7% and the incidence of stroke was 3.7%. The 7-year cardiac survival was 80.4% and the 7-year cardiac event free was 65.0%. The use of arterial graft to the right coronary artery was identified as independent predictor of late cardiac event. Neither total arterial revascularization nor bilateral internal thoracic artery grafting was a significant cardiac event factor. This retrospective study suggests a benefit of the less invasive strategy in terms of operative mortality and morbidity. Application of fast-track treatment in octogenarians appears to be an effective approach to reduce perioperative morbidity and enhance long-term quality of life.

Novel etodolac analog SDX-308 (CEP-18082) induces cytotoxicity in multiple myeloma cells associated with inhibition of beta-catenin/TCF pathway

We have reported previously that R-enantiomer of etodolac (R-etodolac), which is under investigation in phase 2 clinical trials in chronic lymphocytic leukemia, induces potent cytotoxicity at clinically relevant concentrations in multiple myeloma (MM) cells. In this study, we demonstrated that SDX-308 (CEP-18082), a novel analog of etodolac, has more potent cytotoxicity than R-etodolac against both MM cell lines and patient MM cells, including tumor cells resistant to conventional (dexamethasone, doxorubicine, melphalan) and novel (bortezomib) therapies. SDX-308-induced cytotoxicity is triggered by caspase-8/9/3 activation and poly (ADP-ribose) polymerase cleavage, followed by apoptosis. SDX-308 significantly inhibits beta-catenin/T-cell factor pathway by inhibiting nuclear translocation of beta-catenin, thereby downregulating transcription and expression of downstream target proteins including myc and survivin. Neither interleukin-6 nor insulin-like growth factor-1 protect against growth inhibition triggered by SDX-308. Importantly, growth of MM cells adherent to bone marrow (BM) stromal cells is also significantly inhibited by SDX-308. Our data therefore indicate that the novel etodolac analog SDX-308 can target MM cells in the BM milieu.

[Effects of dexmedetomidine hydrochloride on postoperative sedation in cardiovascular surgery]

BACKGROUND

Postoperative assessment of brain damage in cardiovascular surgery is often obscured by sedatives. Therefore, early postoperative detection of brain attack and its treatment are also hampered. A newly approved sedative, dexmedetomidine hydrochloride has weak analgesic effect and no respiratory depressive effect. These characteristics allow early assessment of brain damage after surgery. In this report, we compared 2 sedatives, propofol and dexmedetomidine hydrochloride, in cardiovascular settings.

SUBJECT AND METHODS

Both sedatives were initiated right after admission to the intensive care unit (ICU), followed by titrimetric method targeting for the sedation agitation scale (SAS) from 1 to 4. Thirty-five cases were included in dexmedetomidine hydrochloride group (DEX group) and 16 cases were included in propofol group (Prop group).

RESULTS

Preoperative and operative demographic data were the same between the 2 groups. Conversion rate to another sedatives, and incidence of vasopressor or hypotensor use were both in the same proportion in both groups. Intubated time was the same in both groups. Both systolic and diastolic blood pressures were kept lower in DEX group than Prop group until 8 hours after ICU admission. Other hemodynamic measurements, heart rate, pulmonary artery pressure and cardiac index showed no statistical difference. SAS and Ramsay score were better in DEX group early after ICU admission, and remained better until 10 hours later.

CONCLUSION

Dexmedetomidine hydrochloride has no major hemodynamic nor other side effects after cardiovascular surgery. Dexmedetomidine hydrochloride could be used as an effective agent for postoperative sedation and analgesia in cardiovascular settings.

[Aortic valve replacement in elderly patients with small aortic annulus; is the indexed effective orifice area important?]

We sought to determine whether the small indexed effective orifice area (EOAI) increased mortality and morbidity after aortic valve replacement (AVR) in patients over 75 years of age. From May 1999 to July 2005, 77 patients underwent isolated AVR for aortic stenosis. They were divided into 3 groups (S-EOAI : EOAI < or = 0.7 cm2/m2, M-EOAI : 0.7 cm2/m2 <EOAI < or = 0.85 cm2/ m2, L-EOAI : 0.85cm2/m2 <EOAI) for evaluation. We examined the body surface area (BSA), EOAI, and the left ventricular (LV) mass index (LVMI). We found that patients with S-EOAI had less symptomatic improvement (p <0.05, vs L-EOAI) and LV mass regression (p< 0.01, vs L-EOAI). But, their average New York Heart Association (NYHA) class was improved significantly (2.3 +/- 0.8 vs 1.8 +/- 0.7 : preoperative vs postoperative, p=0.001). Furthermore, severe patient-prosthesis mismatch (PPM) had no significant negative impacts on the freedom of valve-related complications (75.1% : S-EOAI group vs 92.0% : L-EOAI group) and the 5-year survival (84.9% : S-EOAI group vs 87.8% : L-EOAI group). In elderly patients, the average NYHA class was 1.9 +/- 0.6 postoperatively (p<0.0001 vs preoperative) and the LVMI showed significant regression (p<0.0001) despite an average EOAI of 0.73 +/- 0.13 cm2/m2. It is important to consider whether the benefits of avoiding PPM overcome the drawbacks of other complicated techniques. In this study, we found that moderate PPM (0.7 cm2/m2 < or = EOAI) is acceptable to elderly patients.

Invasive phenotype and apoptosis induction of Plesiomonas shigelloides P-1 strain to Caco-2 cells

AIMS

The mechanism of the host cell invasion of Plesiomonas shigelloides and its capability to induce apoptosis were investigated.

METHODS AND RESULTS

We performed a time course experiment on the bacterial adherence and invasion of the P. shigelloides P-1 strain into Caco-2 cells using an invasion assay and flow cytometry. The adherence of P. shigelloides to the Caco-2 cells was almost completed within 10 min after the infection. Thereafter, P. shigelloides starts internalization within the Caco-2 cells, which was completed within 60 min after the infection. Based on the invasion assay using nocodazole, cytochalasin D, and genistein, it became clear that the mechanism of the internalization depended on the signal transduction followed by the rearrangement of the cytoskeletal protein. Based on the DNA laddering and TUNEL methods, the cytotoxicity of the Caco-2 cells by the invasion of P. shigelloides occurred through the induction of apoptosis.

CONCLUSIONS

This work demonstrated that the mechanism of invasion of P. shigelloides into Caco-2 cells and the invasion of P. shigelloides induces apoptotic cell death.

SIGNIFICANCE AND IMPACT OF THE STUDY

This work revealed the virulence factor, which may be important for understanding of the pathogenesis of P. shigelloides.

The subjective dimension of functioning and disability: what is it and what is it for?

The International Classification of Functioning, Disability and Health (ICF, WHO 2001) made a great advancement over ICIDH of 1980 in the understanding of the human functioning and disability. However, in both of them there is an important 'missing' element. That is the subjective dimension of functioning and disability. One of the authors (S. Ueda) published on this topic in 1981 both in Japanese and English. It had originated from his clinical experience in rehabilitation medicine. The understanding of the inner world of the client has proved a great asset in clinical practice. This paper explains its importance and provides a definition. It also proposes a tentative framework of a classification of subjective dimension of functioning and disability as the starting point for more intensive and extensive discussion on this important problem, and for its future inclusion into ICF.

Purification and identification of monoubiquitin-phosphoglycerate mutase B complex from human colorectal cancer tissues

Ubiquitin-conjugated proteins in human colorectal cancer tissues were analyzed by the immunoprecipitation with the antibody FK2 against conjugated ubiquitin followed with SDS-PAGE. In these immunoprecipitable proteins, a 38-kDa protein was abundant in the tumor regions but almost absent in the adjacent normal regions in 17/26 patients, thus we attempted to purify it. Using immunoaffinity chromatography with the antibody FK2 followed by gel filtration and SDS-PAGE, approximately 10 pmol of this protein was separated from 34 g of the pooled cancerous tissue and transferred onto a PVDF membrane. The 38-kDa protein was further digested with Achromobacter protease I, resulting in several peptide fragments. Amino acid sequences of these peptides showed complete sequence identity to those derived from either ubiquitin or phosphoglycerate mutase-B, suggesting that the 38-kDa protein is monoubiquitinated phosphoglycerate mutase-B, whose calculated mass is 37,369 Da. Western blot using an antibody against phosphoglycerate mutase-B revealed the presence of the 38-kDa protein in the anti-ubiquitin immunoprecipitates derived from the tumor regions, but not from normal counterparts. In addition, part of non-ubiquitinated phosphoglycerate mutase-B (29 kDa) was also found in the anti-ubiquitin immunoprecipitates, whose levels were higher in the tumor regions than in the adjacent normal regions. These results suggest that monoubiquitination of phosphoglycerate mutase-B as well as formation of a noncovalent complex containing ubiquitin and phosphoglycerate mutase-B increases in colorectal cancer and novel modification of phosphoglycerate mutase-B might have a pathophysiological role.

Clinical studies of bioabsorbable poly-L-lactide sternal coaptation pins

BACKGROUND

Median sternotomy has become the most commonly used incision in cardiac surgery. Since sternal dehiscence, however, is a major complication, we used bioabsorbable poly-L-lactide (P-L-LA) sternal coaptation pins for sternal closure to prevent it.

METHODS

From February 1998 to October 1999, 99 patients (64 men, 35 women; mean age, 63+/-1.2 years) underwent median sternotomy for cardiac surgery using sternal coaptation pins. Nineteen patients had diabetes mellitus and seven had renal failure. In closure, two sternal pins were inserted into the bone marrow of the sternum, one into the manubrium, the other into the body, and the sternum was sutured with five stainless steel wires.

RESULTS

Five patients died in the hospital. The causes of death were cardiac failure in two patients, respiratory problem in two and perforation of the stomach in one. The average length of hospitalization was 2 4.5+/-2.5 days. Sternal dehiscence occurred in one patient and mediastinitis in four. There was no bleeding from the bone marrow and no complication related to the use of the sternal pins.

CONCLUSIONS

P-L-LA sternal pins were easy to insert and may be effective in preventing dehiscence of the sternum.

Identification and characterization of the human serotonin-4 receptor gene promoter

The human serotonin-4 (5-HT(4)) receptor gene expression is highly regulated in various tissues. We isolated the human 5-HT(4) receptor gene containing the 5'-flanking region and characterized its promoter. By 5'-RACE (5'-rapid amplification of the cDNA ends) and inverse PCR, multiple transcription initiation sites were identified. The most 5' one (assigned to +1) was 5135 bp upstream to the translation start site. The 500-bp 5'-flanking region contained potential binding sites for transcription factor Sp-1, AP-2, AP-4, and GATA. However, this region lacked TATA- and CAAT-boxes. Transient transfection analyses in human choriocarcinoma T3M-3 (5-HT(4) receptor-positive) and HepG2 (5-HT(4) receptor-negative) cells revealed that the region (-210 to -105) is necessary for the basic and cell-type specific 5-HT(4) receptor gene expression. In addition, untranslated exon 1 contained negative (+112 to +182) as well as positive (+1 to +111) modulators, indicating that exon 1 plays a regulatory role in the 5-HT(4) receptor gene expression.

Isolation of ubiquitin-E2 (ubiquitin-conjugating enzyme) complexes from erythroleukaemia cells using immunoaffinity techniques

A variety of ubiquitin-associated (or conjugated) proteins, including substrates and enzymes for the ubiquitin system, are present in eukaryotic cells. In the present study we developed a simple method for their isolation, consisting of immunoaffinity chromatography using the monoclonal antibody FK2, which recognizes the conjugated ubiquitin molecule. Using this method followed by gel filtration, we isolated multi-ubiquitinated proteins with high molecular masses (>30 kDa) and also ubiquitinthioester-linked and mono-ubiquitinated forms of ubiquitin-conjugating (E2) enzymes, UbcH7 and UBE2N, together with mono-, di- and tri-ubiquitin molecules, from the cytoplasmic extract of heat-shock-treated K562 erythroleukaemia cells. We also demonstrated that the FK2 antibody was capable of precipitating a ubiquitin-UbcH7 thioester, but not free UbcH7, which enabled the measurement of the respective cellular levels separately. The immunoprecipitable ubiquitin-UbcH7 thioester was found only when the cells were treated with heat-shock. These results suggest the usefulness of the immunoaffinity techniques for identifying and analysing the cellular enzyme/protein-ubiquitin complexes.

Calpain inhibitor inhibits secretory granule maturation and secretion of GH

Clathrin- and AP-1-coated buds are present on immature secretory granules of endocrine cells that mature into clathrin-uncoated granules. The mechanism of clathrin and adaptor protein uncoating has remained obscure. Benzyloxycarbonyl-L-leucyl-L-leucinal (ZLLal), a calpain inhibitor, reduced growth hormone (GH) secretion with intracellular accumulation, in a GH-secreting rat pituitary tumor cell. Pulse and chase demonstrated that ZLLal retarded the turnover of clathrin (Clt.H) and adaptins. ZLLal-treatment co-immunoprecipitated the increased amounts of GH with Clt.H and adaptins compared to control cells, suggesting the intracellular accumulation of immature secretory granules. Clt.H and adaptins were limited-proteolyzed by m-calpain in vitro, indicating that calpain may be involved partly in the maturation of secretory granules in endocrine cells via the process of clathrin uncoating.

Comparison of standard coronary artery bypass grafting and minimary invasive direct coronary artery bypass grafting. Early and mid-term result

OBJECTIVES

We studied indications and problems involved in minimally invasive coronary artery bypass grafting (MIDCAB).

METHODS

We compared patients profiles, graft patency, stenosis severity, morbidity, mortality, long-term survival and freedom from cardiac accidents in 174 patients undergoing elective standard coronary artery bypass grafting (CABG) and 128 undergoing between January 1996 and March 1999.

RESULTS

No statistically difference was seen in gender, diabetes mellitus, renal failure, cerebrovascular accident, multi-vessel disease ratios, or left main trunk stenosis between 2 groups. Internal thoracic artery graft patency was 97% (114/118) and the rate of anastomotic stenosis (> 50%) was 9% (10/118) compared to 96% (213/221) in the MIDCAB group. The 3-year survival rate was 91% in the MIDCAB group and 92% in the CABG group and freedom from cardiac accidents, most involving pericutaneus transluminal coronary angioplasty retreatment, was 66% in the MIDCAB group and 88% in the CABG group.

CONCLUSION

Although patency and stenosis incidence did not differ between 2 groups, freedom from cardiac accidents was lower in the MIDCAB group.