Impact of surgical treatment on lipid metabolism in patients with lumbar spinal disorders: Prospective observational study

PURPOSE

It is still unclear how lumbar spinal surgery affects the lipid metabolism of patients with lumbar spinal disorders (LSDs) such as lumbar spinal canal stenosis and lumbar disk herniation. The present study aimed to assess the impact of lumbar spinal surgery on lipid metabolism in patients with LSDs and clarify the factors associated with changes in visceral fat (VF) accumulation before and after lumbar spinal surgery.

METHODS

Consecutive patients with lumbar spinal surgery for LSDs were prospectively included. Abdominal computed tomography images and blood examination of the participants were evaluated before surgery and at 6 months and 1 year after surgery. The cross-sectional VF area (VFA) was measured at the level of the navel using computed tomography images. Blood examination items included triglycerides and high-density lipoprotein (HDL).

RESULTS

The study enrolled a total of 138 patients. Female patients with LSDs had significantly increased VFA and serum triglyceride levels after lumbar spinal surgery. On multivariable analysis, the group with > 100 cm2 of preoperative VFA and a postoperative decrease in VFA had a significantly worse preoperative walking ability based on the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (relative risk 2.1; 95% confidence intervals 1.1-4.1).

CONCLUSIONS

The present study demonstrated that patients with LSDs did not necessarily improve their lipid metabolism after lumbar spinal surgery. Instead, female patients with LSDs had significantly deteriorated lipid metabolism after lumbar spinal surgery. Finally, a worse preoperative walking ability was associated with the improvement in excess VF accumulation after lumbar spinal surgery.

Seasonal variation in incidence and causal organism of surgical site infection after PLIF/TLIF surgery: A multicenter study

BACKGROUND

Postoperative SSI is a common and potentially serious complication in spine surgery. Seasonal variation occurs in rates of nosocomial infection, with higher rates found in the summer, during which hot, humid conditions may be optimal for proliferation of bacteria. This might also influence the rate of SSI. The purpose of the study was to examine seasonal variation in SSI after PLIF/TLIF surgery, including relationships with experience of surgeons and causal organisms.

METHODS

Cases with SSI after PLIF/TLIF surgery at 10 facilities between January 1, 2012, and December 31, 2014 were retrieved from a database. Infection was defined based on CDC guidelines for SSIs. Patients were followed for at least two years after surgery. Surgeries were examined in spring (April-June), summer (July-September), autumn (October-December), and winter (January-March). Seasonal variation and other factors with a potential association with SSIs were evaluated.

RESULTS

A total of 1174 patients (607 males, 567 females) who underwent PLIF/TLIF surgery were identified. The operations were PLIF (n = 667), TLIF (n = 443), MIS-PLIF (n = 27), and MIS-TLIF (n = 37). The total SSI rate for the 2-year period was 2.5% (29/1174), and the 2-year average SSI rates for surgeries in each season were spring, 2.6% (7/266); summer, 3.9% (13/335); fall, 1.3% (4/302); winter, 1.8% (5/271). The SSI rate was significantly higher in summer than non-summer (3.9% vs. 1.9%, p < 0.05). SSIs were caused by a variety of pathogens, including Gram-positive cocci, and Staphylococcus aureus was the most common pathogenic organism to cause SSI.

CONCLUSION

Seasonality should be taken into account in strategies for SSI prevention, with particular attention on mitigation of increased temperature and humidity in the summer and on infection caused by Gram-positive cocci and S. aureus.

Predictors of Prolonged Length of Stay After Lumbar Interbody Fusion: A Multicenter Study

STUDY DESIGN

Retrospective analysis of a prospectively database.

OBJECTIVES

To identify factors associated with prolonged length of stay (LOS) in posterior /transforaminal lumbar interbody fusion (PLIF/TLIF).

METHODS

The subjects were patients who underwent PLIF/TLIF at 10 facilities from 2012 to 2014. A total of 1168 such patients with a mean age of 65.9 ± 12.5 years (range 18-87 years) were identified in the database. Operations were PLIF (n = 675), TLIF (n = 443), minimally invasive surgery (MIS)-PLIF (n = 22), and MIS-TLIF (n = 32). Age, gender, body mass index, ambulatory status, comorbidities, perioperative American Society of Anesthesiologists (ASA) grade, operative factors, and complications were examined. LOS was defined as the number of calendar days from the operation to hospital discharge. LOS was categorized as normal (<75th percentile) or prolonged (≥75th percentile).

RESULTS

The average LOS was 20.8 ± 9.8 days (range 7-77 days). There was a significant correlation between LOS and age (P < .05). Reoperation during hospitalization was performed in 20 cases for surgical site infection (n = 12), epidural hematoma (n = 5), and screw misplacement (n = 3). In multivariate analysis, prolonged LOS was associated with preoperative variables of age ≥70 years (odds ratio [OR] 1.87, 95% CI 1.38-2.54), and ASA class ≥III (OR 1.52, 95% CI 1.04-2.25); surgical variables of open procedures (OR 5.84, 95% CI 1.74-19.63), fused levels ≥3 (OR 5.17, 95% CI 3.17-8.43), operative time ≥300 minutes (OR 1.88, 95% CI 1.15-3.07), and estimated blood loss ≥500 mL (OR 1.71, 95% 1.07-2.75).

CONCLUSIONS

The factors identified in this study should help with obtaining informed consent, surgical planning and complication prevention to reduce health care costs associated with prolonged LOS.

Trends of postoperative length of stay in spine surgery over 10 years in Japan based on a prospective multicenter database

OBJECTIVES

To identify factors associated with prolonged length of stay (LOS) in spine surgery, with the goal of establishing details of LOS for multiple diseases and surgical procedures.

PATIENTS AND METHODS

The subjects were patients who underwent spine surgery at 10 facilities in the Nagoya Spine Group from January 2005 to December 2015. Data were collected for patient background, primary spinal pathology, anatomical location of the lesion, and surgical methods. The primary outcome was LOS, which was defined as the calendar days from surgery to hospital discharge.

RESULTS

A total of 10,829 patients (5953 males, 4876 females; age 5-93 years, mean 60.2 ± 28.8 years) were identified in the database. Average follow-up was 61 months (range: 13-120 months). Average LOS was 22.3 ± 21.3 days, and there was a gradual decrease in LOS over the study period. LOS was significantly correlated with age, and prolonged LOS was significantly associated with thoracic spine surgery and significantly longer after surgery with instrumentation. Average LOS was >30 days for intramedullary tumor resection and posterior cervical fusion, but only 10.2 days for microendoscopic discectomy. Reoperation was performed in 210 patients (1.9%) and these patients had a significantly higher average LOS of 43.1 days.

CONCLUSION

These results will assist quality improvement in spine surgery. The identified risk factors for prolonged LOS will also assist in planning of surgery, postoperative care, and discharge, with the goal of reducing health care costs.

Postoperative Complications Associated With Spine Surgery in Patients Older Than 90 Years: A Multicenter Retrospective Study

STUDY DESIGN

A review of a prospective database.

OBJECTIVES

Surgery for elderly patients is increasing yearly due to aging of society and the desire for higher quality of life. The goal of the study was to examine perioperative complications in spine surgery in such patients.

METHODS

A multicenter study of surgical details and perioperative complications was performed in 35 patients aged older than 90 years who underwent spinal surgery, based on a review of a prospective database. The frequency and severity of complications were assessed, and the effects of patient-specific and surgical factors were examined. Major complications were defined as those that were life threatening, required reoperation in the perioperative period or left a permanent injury. Ambulatory function before and after surgery was also analyzed.

RESULTS

Perioperative complications occurred in 19 of the 35 cases (54%), and included 11 cases of postoperative delirium, most of which occurred after cervical spine surgery. There were 8 major complications (23%), including cerebral infarction (n = 3), coronary heart disease (n = 3), pulmonary embolism (n = 1), and angina (n = 1). Preoperative motor deficit, operative time, estimated blood loss, and instrumented fusion were significantly associated with major complications. An improved postoperative ambulatory status occurred in 61% of cases, with no change in 33%, and worsening in 2 cases (6%).

CONCLUSIONS

Timing of surgery before paralysis progression and reduced surgical invasiveness are important considerations in treatment of the very elderly. Improved outcomes can be obtained with better management of spine surgery for patients aged 90 years or older.

Enhanced biomass production of duckweeds by inoculating a plant growth-promoting bacterium, Acinetobacter calcoaceticus P23, in sterile medium and non-sterile environmental waters

Duckweed offers the promise of a co-benefit culture combining water purification with biomass production. Acinetobacter calcoaceticus P23 is a plant growth-promoting bacterium isolated from a duckweed, Lemna aequinoctialis. This study quantified its growth-promoting effect on three duckweeds (L. aoukikusa, L. minor, and Spirodela polyrhiza) in sterile Hoagland solution and evaluated its usefulness in duckweed culture under non-sterile conditions. P23 promoted growth of three duckweeds in sterile Hoagland solution at low to high nutrient concentrations (1.25-10 mg NO₃-N/L and 0.25-2.0 mg PO₄-P/L). It increased the biomass production of L. aequinoctialis 3.8-4.3-fold, of L. minor 2.3-3.3-fold, and of S. polyrhiza 1.4-1.5-fold after 7 days compared with noninoculated controls. P23 also increased the biomass production of L. minor 2.4-fold in pond water and 1.7-fold in secondary effluent of a sewage treatment plant under non-sterile conditions at laboratory-scale experiments. P23 rescued L. minor from growth inhibition caused by microorganisms indigenous to the pond water. The results demonstrate that the use of P23 in duckweed culture can improve the efficiency of duckweed biomass production, and a positive effect of P23 on duckweed-based wastewater treatment can be assumed.

[Visualization of Anterolateral Ligament of the Knee Using 3D Reconstructed Variable Refocus Flip Angle-Turbo Spin Echo T2 Weighted Image]

Anterolateral ligament (ALL) is one of the lateral structures in the knee that contributes to the internal rotational stability of tibia. ALL has been referred to in some recent reports to re-emphasize its importance. We visualized the ALL on 3D-MRI in 32 knees of 27 healthy volunteers (23 male knees, 4 female knees; mean age: 37 years). 3D-MRIs were performed using 1.5-T scanner [T(2) weighted image (WI), SPACE: Sampling Perfection with Application optimized Contrast using different flip angle Evolutions] in the knee extended positions. The visualization rate of the ALL, the mean angle to the lateral collateral ligament (LCL), and the width and the thickness of the ALL at the joint level were investigated. The visualization rate was 100%. The mean angle to the LCL was 10.6 degrees. The mean width and the mean thickness of the ALL were 6.4 mm and 1.0 mm, respectively. The ALL is a very thin ligament with a somewhat oblique course between the lateral femoral epicondyle and the mid-third area of lateral tibial condyle. Therefore, the slice thickness and the slice angle can easily affect the ALL visualization. 3D-MRI enables acquiring thin-slice imaging data over a relatively short time, and arbitrary sections aligned with the course of the ALL can later be selected.

Different X-linked KDM5C mutations in affected male siblings: is maternal reversion error involved?

Genetic reversion is the phenomenon of spontaneous gene correction by which gene function is partially or completely rescued. However, it is unknown whether this mechanism always correctly repairs mutations, or is prone to error. We investigated a family of three boys with intellectual disability, and among them we identified two different mutations in KDM5C, located at Xp11.22, using whole-exome sequencing. Two affected boys have c.633delG and the other has c.631delC. We also confirmed de novo germline (c.631delC) and low-prevalence somatic (c.633delG) mutations in their mother. The two mutations are present on the same maternal haplotype, suggesting that a postzygotic somatic mutation or a reversion error occurred at an early embryonic stage in the mother, leading to switched KDM5C mutations in the affected siblings. This event is extremely unlikely to arise spontaneously (with an estimated probability of 0.39-7.5 × 10(-28) ), thus a possible reversion error is proposed here to explain this event. This study provides evidence for reversion error as a novel mechanism for the generation of somatic mutations in human diseases.

Low-intensity pulsed ultrasound therapy stimulates callus formation between host femur and cortical onlay strut allograft

Cortical onlay strut allografting is a promising surgical option to reconstruct and reinforce the deficient femur in a hip arthroplasty. However, the union of the allograft to the host bone takes a long time. To accelerate the process of cortical onlay strut allograft healing, we studied the effects of low-intensity pulsed ultrasound (LIPUS) on callus formation. From 2 wk after the operation, LIPUS was given for 20 min/d at each end of the strut allograft. The LIPUS treatment group was assigned 14 allograft transplantations, while 21 control patients were treated without LIPUS. The LIPUS treatment group formed calluses and had complete bridging between the host femur and the allograft faster after operation (16.9 and 29.4 wk after operation, respectively) compared with the control group (40.7 and 82.0 wk after operation, respectively). Our findings showed that LIPUS stimulated bone bonding between the host femur and the cortical onlay strut allografts.

Nationwide investigation into adverse tissue reactions to metal debris after metal-on-metal total hip arthroplasty in Japan

BACKGROUND

Adverse reactions to metal debris (ARMD) after receiving metal-on-metal (MoM) hip implants is a recent concern. However, no epidemiologic study has examined ARMD for MoM hip implants in Japan. The purposes of this study were to research the incidence of ARMD and to identify poorly performing MoM hip implants in Japan.

METHODS

From 2000 to 2011, 7 companies provided 23,226 MoM implants in Japan. A questionnaire regarding ARMD was sent to 101 hospitals at which 62% of the 23,226 MoM implants had been used.

RESULTS

Replies to the questionnaire were received from 82 hospitals. In these hospitals, surface hip replacement types (SRs) were used in 606 hips and stemmed types were used in 12,961 hips. ARMD were reported in 3 hips (0.5%) with SRs and 160 hips (1.2%) with stemmed types. ARMD in the 3 hips with SRs were asymptomatic and no revisions were performed. Among AMRD with stemmed implants, revision was performed in 83 hips and excision of an ARMD lesion was performed in 3 hips. The remaining 74 hips were asymptomatic and careful follow-up was continued. A significant difference in reoperation rate was evident between SRs (0%) and stemmed types (0.7%). Incidences of ARMD were significantly higher with Ultamet (P = 0.005), Conserve (P < 0.001), and Cormet (P < 0.001) MoM bearing couples than with Metasul bearings.

CONCLUSIONS

The incidence of ARMD in large surgical volume hospitals in Japan from 2000 to 2011 was estimated to be 0.5% with SRs and 1.2% with stemmed types. The reoperation rate was significantly higher with stemmed types than with SRs. Three brands of MoM stemmed implants were identified as showing a higher incidence of ARMD.

Bone union rate with autologous iliac bone versus local bone graft in posterior lumbar interbody fusion (PLIF): a multicenter study

PURPOSE

The purpose of this study is to compare bone union rate between autologous iliac bone and local bone graft in patients treated by posterior lumbar interbody fusion (PLIF) using carbon cage for single level interbody fusion.

METHODS

The subjects were 106 patients whose course could be observed for at least 2 years. The diagnosis was lumbar spinal canal stenosis in 46 patients, herniated lumbar disk in 12 patients and degenerative spondylolisthesis in 51 patients. Single interbody PLIF was done using iliac bone graft in 53 patients and local bone graft in 56 patients. Existence of pseudo-arthrosis on X-P (AP and lateral view) was investigated during the same follow up period.

RESULTS

No significant differences were found in operation time and blood loss. Significant differences were also not observed in fusion grade at any follow up period or in fusion progression between the two groups. Donor site pain continued for more than 3 months in five cases (9%). The final fusion rate was 96.3 versus 98.3%.

CONCLUSIONS

Almost the same results in fusion were obtained from both the local bone group and the autologous iliac bone group. Fusion progression was almost the same. Complications at donor sites were seen in 19% of the cases. From the above results, it was concluded that local bone graft is as beneficial as autologous iliac bone graft for PLIF at a single level.

Risk factors for a poor outcome following surgical treatment of cervical spondylotic amyotrophy: a multicenter study

INTRODUCTION

Cervical spondylotic amyotrophy (CSA) is characterized by muscle atrophy in the upper extremities without gait disturbance. However, the indications and outcomes of surgical treatment for CSA have not been clarified. The purpose of this study was to determine the risk factors for a poor outcome following surgical treatment of CSA.

MATERIALS AND METHODS

We performed a retrospective review of CSA in patients from 1991 to 2010 through a multicenter study. We collected information regarding age, type of muscle atrophy, preoperative manual muscle test (MMT), duration of symptoms, high-intensity areas on T2-weighted MR images, low-intensity areas on T1-weighted MR images, levels of spinal canal stenosis, cervical kyphosis and surgical procedures (laminoplasty, anterior cervical discectomy and fusion and posterior spinal fusion), and calculated overall risk factors related to a poor outcome following surgery. Univariate analyses and multivariate logistic regression analysis were performed to identify correlates of a poor outcome.

RESULTS

Fifty-nine patients, 95 % male (56 patients), were included in our analysis with a mean age of 59 years (range 32-78 years). Eighteen patients did not improve after surgery. Symptom duration (OR = 1.263), preoperative MMT grade (OR = 0.169) and distal type of CSA (OR = 9.223) were all associated with an increased risk of a poor surgical outcome.

CONCLUSION

Early surgery is recommended for CSA patients in whom conservative treatment has not been successful. We also recommend surgery for patients who have severe preoperative muscle weakness or have the distal type of CSA.

Incidence of complications associated with spinal endoscopic surgery: nationwide survey in 2007 by the Committee on Spinal Endoscopic Surgical Skill Qualification of Japanese Orthopaedic Association

BACKGROUND

This report was conducted to elucidate the current status of spinal endoscopic surgery and relevant incidents through analysis of the results of a questionnaire survey conducted in 2007 by the Committee on Spinal Endoscopic Surgical Skill Qualification of the Japanese Orthopaedic Association (JOA).

METHODS

Questionnaire forms were sent to 2011 training facilities nationwide certified by the JOA, and 1082 of these facilities returned the filled questionnaires (response rate 53.8%). Of these facilities, 257 (23.8% of the responding facilities) undertook spinal endoscopic surgery in 2007. These institutions were asked to fill in the survey form with the details of the operations and relevant incidents as well as the incident levels.

RESULTS

In total, the 257 facilities performed 6239 spinal endoscopic surgeries during 2007. Posterior spinal endoscopic surgery constituted most of the operations (6217 cases, 98.2%) including 4336 cases of microendoscopic discectomy (MED), 1273 cases of microendoscopic laminectomy or fenestration, and 379 cases of transforaminal or posterior lumbar interbody fusion. The total number of incidents was 133 (2.13%). The numbers of incidents by operative method were 75 (56.4%) during MED, 57 (42.9%) during microendoscopic laminectomy or fenestration, and 1 (0.8%) during interbody fusion. Of 133 incidents, dural tear occurred in 99 (74.4%), injury of the cauda equina or a nerve root in 7 (5.3%), facet fracture in 7 (5.3%), hematoma and wrong level in 6 each (4.5%), and wrong side and bedsore in 1 each (0.8%). The incident level was level 1 in 6, level 2 in 24, level 3a in 82, level 3b in 16, level 4 in 5, and level 5 (fatal) in 0.

CONCLUSIONS

The results of this survey revealed an increasing trend of spinal endoscopic surgery and a decreasing trend of the complication rates. The complication rates of spinal endoscopic surgery were not higher than those of conventional surgery, indicating the safety of this surgical method.

Serial evaluation of human anterior cruciate ligament grafts by contrast-enhanced magnetic resonance imaging: comparison of allografts and autografts

PURPOSE

The purpose of this study was to clarify the difference in remodeling between allografts and autografts in anterior cruciate ligament reconstruction.

METHODS

We examined 24 knees with bone-patellar tendon-bone allografts and 20 knees with central-third bone-patellar tendon-bone autografts. Surgical patients from January 1997 to December 2002 were included in the study, and more than 1 year had passed since surgery. The mean postoperative follow-up was 24.0 months in the allograft group and 21.3 months in the autograft group. Patients with a positive Lachman test were excluded. The operative method and postoperative rehabilitation programs were the same. All allografts were provided by Tokai Regional Bone Bank, the only regional bone bank in Japan. Contrast-enhanced magnetic resonance imaging (1.0 T, T1-weighted, sagittal section, infusion of 0.2-mL/kg gadolinium-diethylenetriamine pentaacetic acid [Gd-DTPA]) was performed for all knees at 1, 4, 6, and 12 months after surgery and performed for some knees irregularly thereafter. The signal/noise quotient (SNQ) of grafts was calculated by use of magnetic resonance imaging based on the method of Weiler et al. (2001) as follows: SNQ = (Signal of ACL graft - Signal of quadriceps tendon)/Signal of background.

RESULTS

The SNQ of allografts was significantly lower than for autografts 12 months after surgery. As for the SNQ 1 month after surgery, there was no difference before or after Gd-DTPA infusion in the allografts; however, the SNQ was significantly higher after Gd-DTPA infusion in autografts. The SNQ after Gd-DTPA infusion continued to increase until 12 to 24 months in the allograft group but peaked at 4 or 6 months in the autograft group.

CONCLUSIONS

Compared with autologous tendons, allogeneic tendons have a slower onset and rate of revascularization.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Current trends in bone grafting and the issue of banked bone allografts based on the fourth nationwide survey of bone grafting status from 2000 to 2004

BACKGROUND

The Japanese Orthopaedic Association Committee on Tissue Transplantation and Regenerative Medicine has conducted a nationwide survey of the status of bone grafting in Japan every 5 years from 1985. We report here the status of bone grafting from 2000 to 2004, show the trends in bone grafting from 1985 to 2004, and draw attention to the issues affecting banked bone allografts.

METHODS

Questionnaires devised by the Committee were sent to all educational and training hospitals (2239 institutions) approved by the Japanese Orthopaedic Association.

RESULTS

Survey responses were obtained from 1263 institutions (56%). Of these, 875 institutions performed tissue transplantation during this period. A total of 163 564 tissue transplantations were performed, and 134 782 (82.4%) of them were bone grafts. Of the bone grafts, 76 015 (56.4%) were autografts, 53 735 (40%) used a synthetic bone substitute, and 4886 (3.6%) were banked bone allografts. The proportion of synthetic bone substitutes increased, and the proportion of autografts decreased year by year. Synthetic bone substitutes were most frequently used for replacement arthroplasty (31%). Fifty percent of banked bone allografts were performed for joint disorders requiring replacement arthroplasty. During this period, 271 institutions performed banked bone allografts, with 210 preserving allografts in their own institutions. Donor selection criteria, processing and preservation methods, and management of the bone bank were not the same in all banks.

CONCLUSIONS

Most bone grafts performed in Japan during the four surveys were still autografts. However, the proportion of autografts decreased, and the proportion of synthetic bone substitutes increased. The number of synthetic bone substitutes and banked bone allografts used for replacement arthroplasty increased significantly. However, the total number of banked bone allografts reported in the fourth survey was still low. Quality control of banked bone allografts and management of bone banks were not satisfactory, although they were improved.

[Oral osteoporosis: a review and its dental implications]

In post-menopausal osteoporosis, lack of estrogen will affect the remodeling of the bone tissue in such a way that, in most patients with periodontitis, the amount of bone resorbed exceeds that being formed, resulting in net bone loss. Osteoporosis can be treated by a variety of methods, the hormone replacement therapy (HRT), the selective estrogen receptor modulators (SERM) and the bisphosphonates. The HRT or bisphosphonates treatments improve the clinical outcome of periodontal disease and may be an adjunctive treatment to preserve periodontal bone mass. This paper reviews the current evidence on the mechanism of periodontal breakdown after menopause and the benefit to oral health by treatments for osteoporosis.

Salvage operation for persistent low back pain and sciatica induced by percutaneous laser disc decompression performed at outside institution: correlation of magnetic resonance imaging and intraoperative and pathological findings

OBJECTIVE

We identified several problems associated with percutaneous lumbar disc decompression (PLDD) based on a study of patients who required salvage operations for complications after undergoing PLDD at an outside institution.

BACKGROUND DATA

PLDD has been performed as a new treatment for intervertebral disc herniation in recent years, and its safety and effectiveness are in the process of being established. Because the procedure is simple to perform under local anesthesia, inappropriate irradiation and application to patients for whom it is not indicated have sometimes resulted in a poor outcome and serious complications.

METHODS

The patients comprised 10 with lumbar disc herniation and three with lumbar spondylolisthesis. We analyzed the magnetic resonance (MR) imaging and operative findings as well as the pathological features of surgically obtained disc specimens and studied their relationships with the clinical outcomes of the operations.

RESULTS

Initial examination of all patients at our hospital showed that PLDD had no effect on low back pain or sciatica. In patients who showed MR signal changes in the end-plate, the pathological examination revealed extensive necrosis of cartilage and bone. During salvage operations, severe adhesion of herniated masses to nerve roots was often observed, with carbonized disc tissue surrounding the nerve roots and might have their nerve root injured thermally.

CONCLUSION

PLDD is associated with significant risk of disc, end-plate, and nerve root injuries, contrary to the general belief that the procedure is minimally invasive. Our findings highlight the need for careful diagnosis and sufficient technical skill when selecting PLDD as a treatment option.

[Osteoporosis and periodontal disease in postmenopausal women: association and mechanisms]

Many studies have attempted to define the relationship between postmenopausal osteoporosis and periodontal disease. Most studies support a positive association between these common diseases; however, many are cross-sectional in nature, include relatively small sample sizes, and have inadequate control of potential confounding factors, such as age, gender, hormone intake, race, and smoking, limiting our understanding of the nature of the relationship between these diseases. Clinical conditions causing low estrogen environments in postmenopausal women allow T- and B-cell abnormalities, increased local production of the bone-active cytokines (i.e., Interleukin-1, -6 and -8, tumor necrosis factor [TNF]-alpha) and a rise in prostaglandin E(2), resulting in the progression of periodontitis.

[Osteoporosis and periodontal disease in postmenopausal women]

Many studies have attempted to define the relationship between postmenopausal osteoporosis and periodontal disease. Most studies support a positive association between these common diseases; however, many are cross-sectional in nature, include relatively small sample sizes, and have inadequate control of potential confounding factors, such as age, gender, hormone intake, race, and smoking, limiting our understanding of the nature of the relationship between these diseases. Clinical conditions causing low estrogen environments in postmenopausal women allow increased local production of the bone-active cytokine and the progression of periodontal disease. Prospective studies are needed to confirm or refute a causal relation.

Age related expression of Werner's syndrome protein in selected tissues and coexpression of transcription factors

AIMS

Werner's syndrome (WS) is an uncommon autosomal recessive disease resulting from mutational inactivation of human WRN helicase, Werner's syndrome protein (WRNp). Patients with WS progressively develop a variety of aging characteristics after puberty. The aim of this study was to determine the distribution of WRNp and the expression of the transcription factors regulating WRN gene expression in a variety of human organs in an attempt to understand the WS phenotype.

METHODS

Tissue specimens were obtained from 16 controls aged from 27 gestational weeks to 70 years of age and a 56 year old female patient with WS. The distribution of WRNp and the expression of the transcription factors regulating WRN gene expression-SP1, AP2, and retinoblastoma protein (Rb)- were studied in the various human organs by immunohistochemical and immunoblot analyses.

RESULTS

In the healthy controls after puberty, high expression of WRNp was detected in seminiferous epithelial cells and Leydig cells in the testis, glandular acini in the pancreas, and the zona fasciculata and zona reticularis in the adrenal cortex. In addition, the SP1 and AP2 transcription factors, which regulate WRNp gene expression, appeared in an age dependent manner in those regions where WRNp was expressed. In controls after puberty, SP1 was expressed in the testis and adrenal gland, whereas AP2 was expressed in the pancreas.

CONCLUSIONS

These findings suggest that the age specific onset of WS may be related to age dependent expression of WRNp in specific organs.

Development of the acetabulum and the acetabular labrum in the normal child: analysis with radial-sequence magnetic resonance imaging

The degree of acetabular and labral coverage was clarified in children at different positions using radial-sequence magnetic resonance imaging. Scans were performed on 40 hips in 20 normal children (group A, 6-8 years old; group B, 9-11 years old; group C, 12-13 years old) and on 19 hips of 10 healthy adults as controls. The degrees of coverage of the femoral head by acetabulum, acetabular labrum, and both were measured at seven positions at every 15 degrees from anterosuperior 45 degrees via midsuperior to posterosuperior 45 degrees. Coverage of the femoral head by the acetabulum in young children was less than in adults at all positions, but the total coverage including the labrum was greater than in adults. Development of the acetabulum and the acetabular labrum showed differences by position.

Development of GABAergic neurons and their transporter in human temporal cortex

The gamma-aminobutyric acid (GABA) system plays an important role in the early development of the hippocampal formation. The immunohistochemical expression of gamma-aminobutyric acid transporter-1, GAT-1, in the human developing temporal cortex was examined, and the distribution of GAT-1 was compared with that of the 67-kDa isoform of glutamic acid decarboxylase as a marker of GABAergic neurons. Four postmortem tissue specimens from young patients with hippocampal sclerosis were also examined. GAT-1 immunoreactivity was present, with a few puncta, in the neuropil of the stratum oriens and in the molecular layer of the dentate gyrus from 21-22 weeks of gestation, and in the stratum lacunosum-moleculare from 26 weeks of gestation. The peak expression of GAT-1 was seen in early infancy and that of glutamic acid decarboxylase in the perinatal period. These findings may reflect the development of GABAergic inhibitory systems, and may be related to the seizure susceptibility in infancy and early childhood. In the temporal lobes with hippocampal sclerosis, GAT-1 immunoreactivity of the neuropil was preserved in the vicinity of the neuronal loss of the hippocampus. This finding may result from the neurotrophic function of GAT-1 and may be related to its ability of neuronal repair and plasticity in childhood.

The effect of heat-treated human bone morphogenetic protein on clinical implantation

For the clinical usage of human-derived bones, it is necessary to treat bones to reduce the risk of contamination by microorganisms. Bone morphogenetic protein is vulnerable to chemicals, but shows resistance to thermal heat to 70 degrees C in a short time. In this experiment, crude human bone morphogenetic protein was extracted from heat-treated bones at 60 degrees C for 10 hours and from nonheated bones. Sodium dodecyl sulfate polyacrylamide gel electrophoresis for these specimens was done. Gelatin capsules containing 5 mg of crude human bone morphogenetic protein extracted from heated and nonheated bones were implanted into thigh muscle pouches of five mice. At 20 days after implantation, the heterotopic bone formation was compared by evaluating the radiographic and histologic analyses. The sodium dodecyl sulfate polyacrylamide gel electrophoresis pattern of the human bone morphogenetic proteins showed five main bands (16, 22, 28, 35, and 67 kDa) that were almost identical. Heterotopic bone formation observed on the radiograph was induced by crude human bone morphogenetic protein from heated bones in a manner similar to that used for nonheated bones. The results from this study show that heat-treated bone preserves osteoinduction.

Postoperative magnetic resonance imaging of lumbar disc herniation: comparison of microendoscopic discectomy and Love's method

STUDY DESIGN

We performed a study to compare the magnetic resonance imaging findings up to 24 weeks after microendoscopic discectomy or surgery using Love's method in patients with lumbar disc herniation.

OBJECTIVES

The objective was to determine whether or not microendoscopic discectomy was minimally invasive with respect to the nerve roots, cauda equina, and paravertebral muscles by comparing the postoperative magnetic resonance imaging findings in patients treated by microendoscopic discectomy and the conventional Love's method.

SUMMARY OF BACKGROUND DATA

We introduced microendoscopic discectomy as a minimally invasive surgical procedure for lumbar disc herniation in September 1998 and have obtained good results. Microendoscopic discectomy is superior to the conventional Love's method in that it reduces postoperative pain, shortens the duration of hospitalization, and allows earlier resumption of normal activities. However, the effect of microendoscopic discectomy on the nerves and paravertebral muscles has not been evaluated objectively.

METHODS

Enhancement of the nerve roots and paravertebral muscles, as well as the configuration of the cauda equina at the level of herniation, was assessed on axial magnetic resonance images obtained with contrast enhancement using gadolinium-diethylenetriamine penta-acetic acid before surgery and 1, 4, 8, 12, and 24 weeks after surgery in 25 patients who underwent microendoscopic discectomy and 15 patients who were treated using Love's method.

RESULTS

Increased enhancement of the nerve roots was seen in 50.0% of the microendoscopic discectomy group and 46.2% of the Love group at 1 week after surgery. Enhancement of the paravertebral muscles at the surgical site tended to persist for longer in the microendoscopic discectomy group than in the Love group. However, muscle enhancement was widespread in some patients from the Love group. Abnormalities of the cauda equina attributed to surgical invasion were seen in 12.5% of the microscopic discectomy group and 15.4% of the Love group at 1 week after surgery.

CONCLUSIONS

Microendoscopic discectomy had an effect on the nerve roots and cauda equina that was comparable with that of Love's method. The magnetic resonance images of the route of entry failed to show that microendoscopic discectomy is appreciably less invasive with respect to the paravertebral muscles.

Characteristic features of the acetabular labrum in healthy children

Radial magnetic resonance images of the acetabular labrum were obtained on 40 hips of healthy children. There were no right-left or male-female differences. In children aged 11 years or younger, the labrum on the antero-superior weightbearing portion was triangular in shape, and there was an insular-shaped or linear high-intensity area inside; on the mid-superior portion, the labrum appeared as a regular triangular, low-intensity area; and on the postero-superior portion, it was flat. In children aged 12 and 13 years, the shape of the labrum in each portion was similar to that of the younger children, but the high signal intensity area on the antero-superior portion appeared less frequently. The size of the labrum relative to the femoral head was greater in younger children.

Immunohistochemical expression and pathogenesis of BLM in the human brain and visceral organs

Bloom syndrome (BS) involves the clinical features of telangiectatic erythema, immunodeficiency, and an increased risk for cancer. In order to clarify the pathogenetic significance of the responsible gene, BLM, which encodes a protein possessing homology to Escherichia coli RecQ helicase, the immunohistochemistry of BLM was examined in human brains and visceral organs from fetuses to adults and an adult with BS, using anti-BLM antibodies. Purkinje cells exhibited positive BLM immunoreactivity from 21 gestational weeks (GW), which transiently increased at approximately 40 GW. Neurons of the pontine tegmentum were immunolabeled from the early fetal period. In visceral organs, positive BLM immunoreactivity was observed in the Hassal corpuscles in the thymus from 24 GW, in beta-cells in the Langerhans islets of the pancreas from 36 GW, and in sperm cells and sperms of the testes from 11 years of age. But in a patient with BS, it was negative in the pancreas and testis tissues examined. The characteristic effect of BLM on specific cells in different periods suggests that the BLM gene product is closely related to neuronal development as well as immune, insulin secretory and sperm functions, which appear in different periods, and disorders of which are major symptoms of BS.

Significance of cathepsin B accumulation in synovial fluid of rheumatoid arthritis

We measured and compared the activities of various kinds of proteinases, such as cysteine, serine, aspartic, and metalloproteinases, in synovial fluids of 16 patients with rheumatoid arthritis (RA) and 18 patients with osteoarthritis (OA). More than 19-fold higher activity of cathepsin B and about 6-fold higher activity of prolylendopeptidase, compared to those of OA, were accumulated in RA fluid. Moreover, levels of cathepsins B and S using the corresponding sandwich enzyme immunoassays were statistically higher in RA fluid than those in OA. Significant amounts of 41-kDa and 35-kDa procathepsin L were detected in RA fluid using gelatin zymography, while 41-kDa enzyme alone was detected in OA. Cathepsin B in RA fluid could degrade collagen, and this degradation was suppressed by the addition of CA-074, a specific inhibitor of cathepsin B. Therefore, cathepsin B may participate in joint destruction of RA, and its inhibitor may be effective for RA care.

Two hyperandrogenic adolescent girls with congenital portosystemic shunt

We describe two adolescent girls with a congenital portosystemic shunt who exhibited hyperandrogenism in addition to insulin resistant hyperinsulinaemia. Case 1 was referred to our clinic to undergo a routine clinical work-up prior to tonsillectomy at 14 years of age. Mild liver dysfunction was identified and hypogenesis of the portal vein with a congenital portosystemic shunt diagnosed. Primary amenorrhoea and virilization were evident and an endocrinological evaluation revealed hyperandrogenism and insulin resistant hyperinsulinaemia. Case 2 was referred at 15 years of age because of cardiomegaly. Mild liver dysfunction and hyperbilirubinaemia led to a diagnosis of agenesis of the portal vein with a congenital portosystemic shunt. Virilization was evident and an endocrinological evaluation revealed hyperandrogenism and insulin resistant hyperinsulinaemia. The haemodynamics of these patients were similar to those of secondary portosystemic shunt due to liver cirrhosis, which is often associated with hyperinsulinaemia and/or non-insulin dependent diabetes mellitus. On the other hand, hyperandrogenism is associated with certain insulin-resistant conditions with hyperinsulinaemia, including the polycystic ovary syndrome (PCO). Hyperinsulinaemia is believed to cause hyperandrogenism in patients with PCO by stimulating androgen production in both the ovary and adrenal gland. Therefore, in congenital portosystemic shunts, hyperinsulinaemia is also thought to cause hyperandrogenism due to the same mechanism.

CONCLUSION

A certain percentage of female patients with hyperandrogenism, likely including those with polycystic ovary syndrome may also have congenital portosystemic shunts. Our results indicate that serum levels of total bile acids and ammonia are prognostic indicators of this hepatic vascular anomaly.

Early immunohistochemical detection of axonal damage and glial activation in extremely immature brains with periventricular leukomalacia

Extremely low birth weight (ELBW) infants, who died at 12 hours to 7 days after birth, with periventricular leukomalacia (PVL), were examined by means of neuropathological and immunohistochemical methods. Fourteen infants without PVL were used as controls. Anti-beta-amyloid precursor protein (APP), glial fibrillary acidic protein (GFAP), and ionized calcium-binding adaptor molecule 1 (Iba1) antibodies were used as markers for axonal damage, reactive astrocytes and activated microglia, respectively. Thirteen of 14 ELBW infants with PVL showed a widespread distribution of leukomalacia and 10 showed postnatal-onset of leukomalacia. In 12 of the 14 infants with PVL, regions of APP-reactive axons were found multifocally in the cerebral white matter, but 8 of them did not show coagulation necrosis on HE staining. GFAP-positive cells and Iba1-positive cells were markedly found in the white matter of all cases with PVL and slightly in all 14 controls. These results indicated that in ELBW infants, the distribution and formation of PVL foci are widespread and characteristic and so may involve motor and intellectual abilities in ELBW infants. Therefore, the perinatal management to maintain an appropriate cerebral circulation and oxygenation may be very important.

Radial-sequence magnetic resonance imaging in evaluation of acetabular labrum

We investigated the usefulness of a radial-sequence magnetic resonance imaging (MRI) technique in the visualization of the acetabular labrum, which surrounds the acetabulum. In 22 hip joints of 12 volunteers, T2-weighted images were obtained on 24 radial planes of the acetabular rim, set at 15 degrees -intervals, using the small tip angle gradient echo method. We examined 7 planes in the weight-bearing portion. The acetabular labrum in the weight-bearing portion was depicted in good contrast to the surrounding tissues. The shape of the labrum differed among individuals and also in the anterior and posterior portions of the labrum. The signal intensity of the labrum was low or partially moderate. There was a high signal intensity band on the base of the acetabular labrum in several portions, which should be carefully interpreted to avoid confusion with abnormality. We concluded that radial-sequence MRI could be a useful technique for evaluation of the condition of the acetabular labrum in the weight-bearing portion.

[Consent to enrollment in randomized clinical trials]

Multi-facility joint randomized clinical trials for cancer treatment are the most common method of current clinical study. However, the difference in the rate of participation in multi-facility randomized clinical trials may damage the resulting general validity. Therefore, we studied whether the rate of participation in randomized clinical trials is different between university hospitals and other general hospitals using a questionnaire (with anonymity preserved). There were 744 subjects from university hospitals and 339 from general hospitals participating in the study. The results showed that 10.9 percent of those from university hospitals were willing to participate, against 28.1 percent who were not. Of those from general hospitals (public hospitals in this study) 10.6 percent answered that they would participate and 27.4 percent that they would not. Little difference was found in the rate of participation in randomized clinical trials between university hospitals and other general hospitals. The focus is thus on doctors to solve the possible differences between the facilities in further multi-facility joint studies.

MR imaging of perinatal brain damage: comparison of clinical outcome with initial and follow-up MR findings

BACKGROUND AND PURPOSE

The purpose of our study was to determine whether MR studies in the neonatal period are predictive of the neuroradiologic sequelae and clinical outcome in premature and term infants with perinatal brain injury.

METHODS

Thirty subjects (15 premature and 15 term infants) with abnormalities revealed by initial MR studies were reexamined approximately 1 year after birth with both MR imaging and a neurologic assessment. All initial MR studies were performed between 35 and 45 weeks corrected age in premature infants and within 28 days of life in term infants. The initial MR studies were evaluated for deep gray matter involvement, hemispheric parenchymal change, intracranial hemorrhage, and periventricular signal and/or morphologic changes. These MR findings were compared with the follow-up MR findings and with the neurologic outcome.

RESULTS

The development of cerebral palsy in premature infants was related to the following initial MR findings: subependymal hemorrhage associated with parenchymal destruction, periventricular signal alteration with irregularity of the ventricular wall, and widespread cerebral infarction. These MR findings were predictive of the subtypes of cerebral palsy. In term asphyxiated infants, T2 signal alterations of the deep gray matter rather than T1 shortening and diffuse involvement of the hemispheres were predictive of an unfavorable outcome. Both in term and premature infants, focal hemispheric parenchymal lesions alone (including infarction and intracerebral, subdural, intraventricular, and subarachnoid hemorrhage) did not produce poor outcomes.

CONCLUSION

MR studies performed at or near term in either premature or term infants with perinatal brain damage are effective in predicting both late neuroradiologic and clinical outcome.

Serum hyaluronic acid level reflects volume and ATP levels of the liver after extended hepatectomy with and without preoperative portal vein occlusion

The purpose of this study was to examine the hypothesis that the serum hyaluronic acid (HA) level reflects the volume and adenosine triphosphate (ATP) levels of the liver after extended hepatectomy (ExHx) with and without preoperative portal vein occlusion (PVO). Rats were randomly divided into two groups, PVO-ExHx and sham-ExHx. At the first stage, they underwent PVO or sham surgery by an occlusion of the portal vein supplying the left lateral and median lobes or by similar manipulation but without PVO, respectively. Seven days after first-stage surgery, both groups received ExHx exceeding portal vein-occluded lobes, which was the excision of the left lateral, median, and right lateral lobes of the liver reported as a 90% hepatectomy model. On Days 0, 1, 2, and 3 after ExHx, the serum HA concentrations, liver weights, and hepatic ATP levels were determined. Liver volumes were restored to similar levels in both groups, but restoration was faster in the PVO-ExHx group because preoperative PVO allowed the excised liver less volume. Lower serum HA levels were significantly associated with significantly higher hepatic ATP levels and with a lower mortality rate in the PVO-ExHx group. The serum HA level correlated significantly (P < 0.001) with the liver weight and hepatic ATP level. The serum HA level serves as a proxy for clinically important parameters following major hepatic surgery.

Hepatic adenine nucleotides and microsomal cholesterol 7 alpha-hydroxylase activity in the obstructed and freely draining lobes of the liver after selective bile duct obstruction

BACKGROUND

The effect of selective bile duct obstruction (SBDO) on hepatic reserve function of the bile duct obstructed (BDO) and nonobstructed freely draining (FD) lobes of the liver is obscure.

METHODS

The bile duct branches draining from the left lateral and median lobes of the liver were ligated for 4 and 10 days in rats, and hepatic reserve functions in BDO and FD lobes were assessed by microsomal cholesterol 7 alpha-hydroxylase activities and by hepatic adenine nucleotides and energy charge levels. The values were compared with those in the sham-operated control liver. Cholesterol 7 alpha-hydroxylase activities were determined by gas-liquid chromatography--mass spectrometry, and hepatic adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP) levels with high-pressure liquid chromatography.

RESULTS

The histological examination of the BDO lobes showed proliferation and formation of new bile ductules and fibrous connective tissues linking portal areas. Microsomal cholesterol 7 alpha-hydroxylase activities, hepatic energy charge and each adenine nucleotide level did not differ between FD and BDO lobes, and the values were similar to those in the sham-operated liver.

CONCLUSIONS

Selective bile duct obstruction shows no adverse effects on microsomal and mitochondrial functions in both the BDO and FD lobes of the liver.

Hepatic adenine nucleotides and microsomal cholesterol 7 alpha-hydroxylase activity in the obstructed and freely draining lobes of the liver after selective bile duct obstruction

BACKGROUND

The effect of selective bile duct obstruction (SBDO) on hepatic reserve function of the bile duct obstructed (BDO) and nonobstructed freely draining (FD) lobes of the liver is obscure.

METHODS

The bile duct branches draining from the left lateral and median lobes of the liver were ligated for 4 and 10 days in rats, and hepatic reserve functions in BDO and FD lobes were assessed by microsomal cholesterol 7 alpha-hydroxylase activities and by hepatic adenine nucleotide and energy charge levels. The values were compared with those in sham-operated control liver. Cholesterol 7 alpha-hydroxylase activities were determined by gas-liquid chromatography-mass spectrometry, and hepatic adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP) levels with high-pressure liquid chromatography.

RESULTS

The histological examination of the BDO lobes showed proliferation and formation of new bile ductules and fibrous connective tissue linking portal areas. Microsomal cholesterol 7 alpha-hydroxylase activities, hepatic energy charge and adenine nucleotide levels did not differ between FD and BDO lobes, and the values were similar to those in the sham-operated liver.

CONCLUSIONS

Selective bile duct obstruction shows no adverse effects on microsomal and mitochondrial functions in either BDO or FD lobes of the liver.

[A case of so-called carcinosarcoma of the lung]

A 69-year-old male was followed at our institute for the purpose of hemo-dialization. During follow-up, a tumor shadow (phi 6.5 x 7.0 cm) was found in rt. S5 by chest X-ray. This tumor was diagnosed as squamous cell carcinoma by TBLB. Right middle lobectomy (R 2 a) was performed. Histological staging was pT 2 N 2 M 0, stage IIIa. This tumor was cystic, filled with keratin like substance. Histologically, the cyst wall was composed of well differentiated squamous cell carcinoma and sarcomatous stroma which didn't differentiate into bone, cartilage, muscle, and etc. Immunohistologically, sarcomatous stroma was positively stained by vimentin, negatively by keratin and EMA. This patient survived 7 months with recurrence.

[Obesity and liver dysfunction in UOEH employees--multiple regression analysis of the annual physical checkup data of 1991]

For the purpose of evaluating the significance of obesity as a risk factor toward various chronic geriatric diseases, a multiple regression analysis was performed on the annual physical checkup data of UOEH employees in 1991. The following results were obtained. (1) The average obesity index of the UOEH employees showed a progressive and significant increase in the 10 years from 1981 to 1991. (2) A close relation between the obesity index and serum GPT was recognized by elevation of the standard partial regression coefficients of serum GPT to obesity index and that of the obesity index to serum GPT when the data from all 1591 UOEH employees were analysed in one group. This finding was derived from a significant contribution of obesity to the liver dysfunction in the young male obese population under 30 years of age. (3) Systolic blood pressure was related to age rather than the obesity index, indicating that the development of hypertension is more closely related to aging than obesity. (4) No significant relation was found between the serum total cholesterol level and the obesity index in any group analysed. From the above findings, it can be suggested that the obesity in young male employees is more closely related to liver dysfunction than other abnormalities.

[A case of advanced breast cancer with multiple lung metastases responding well to postoperative combined administration of doxifluridine (5'-DFUR) and tamoxifen]

A 72-year-old female with right breast cancer having multiple lung metastases was treated by combined administration of 5'-DFUR at 800 mg/day, and tamoxifen, at 20 mg/day, after standard radical mastectomy. Plain chest X-ray and computed tomography examinations have shown complete disappearance of the multiple lung tumor since the therapy. No serious side effects have been observed during the treatment course, and there has been no definite evidence of tumor recurrence.

Vasogenic edema induced by compression injury to the spinal nerve root. Distribution of intravenously injected protein tracers and gadolinium-enhanced magnetic resonance imaging

The function of the blood-nerve barrier appears quite unique in the nerve root. Protein tracers that were injected into the subarachnoid space passed through the nerve root sheath and entered into the capillary lumen in the endoneurial space but tracers that were injected intravenously did not appear in the endoneurial space. Marked extravasation of protein tracers in the nerve root was induced at the compressed part by strong compression (60 gram force, 30 gram force) and capillaries in the nerve root showed opening of the tight junction accompanied by an increase in vesicular transport under the electron microscope. This situation was reflected as high intensity on Gadolinium-enhanced magnetic resonance imaging. In twenty-one of fifty patients with lumbar disc herniation, the affected nerve root was strongly enhanced by Gadolinium-diethylene-triaminepentaacetic acid, indicating that the blood-nerve barrier in the affected nerve root was broken and intraradicular edema was produced in these cases.

[Comparison of the casual serum triglyceride levels at health check-up with the values during fasting]

Since higher levels of serum triglycerides were frequently found during the UOEH physical check-up for employees and students in 1989, we analysed subjects with higher triglyceride levels and discussed ways of handling them. Blood sampling to determine serum lipids was done between 13:00-15:00. Of the total (males 1257, females 1267), 272 had higher serum triglyceride levels (over 200 mg/dl) (males 246, females 26) (1st TG). One hundred and twenty-one of the group with higher TG levels in the 1st examination were reevaluated by blood sampling the morning after overnight fasting (2nd TG). There was a significant positive correlationship between the TG levels from the 1st examination and those from the 2nd examination (r = 0.62, n = 121, P < 0.0001). The predictive value calculated from the equation between the TG in the first and second measurements was 341.7 mg/dl. There was a 14.9% rate of false negatives in subjects under 341.7 mg/dl on the first TG measurement. However, there were only 6.3% false negatives in the subjects under 250 mg/dl on the first TG measurement. Age, body mass index and serum cholesterol level were significantly higher in the group with the higher TG level on reevaluation (more than 160 mg/dl) than those in the group with the lower TG level on reevaluation (less than 160 mg/dl). We concluded from these results that the casual serum TG levels above 250 mg/dl might be a suitable cut off level in physical check-ups.

[The significance of obesity in UOEH medical students--multiple regression analysis of the annual physical checkup data in 1991]

For the purpose of evaluating the significance of obesity in a young population as a risk factor toward various chronic diseases, a multiple regression analysis was performed on the data from the annual physical checkup of medical students of UOEH in 1991. The following results were obtained. (1) The average obesity index of the students showed a progressive and significant increase in the past 13 years from 1979 to 1991. (2) A close correlation between the obesity index and serum GPT was recognized by elevation of the standard partial regression coefficient of serum GPT to obesity index and that of obesity index to serum GPT when the data from all 617 students was analysed in one group. This finding was intensified in 142 obese students with an obesity index of over 10%, but it was not seen in the remaining non-obese students. (3) The correlation between the obesity index and serum GPT was found solely in the group of students with constant obesity; i.e., whose obesity index was always more than 10% during a maximum of 9 years in the past. (4) Systolic blood pressure was related to the red blood cell count rather than to the obesity index in this young population. (5) No particularly close correlation to serum cholesterol was found with any of 10 representative items examined in this physical checkup, including the obesity index, indicating that the other factors should be related to serum cholesterol levels. From the above findings, it can be concluded that constant obesity in students is related to liver dysfunction, probably due to fatty liver frequently seen in the precise examination of these individuals.