Biomechanical Comparisons of Different Reconstructive Techniques for Scapholunate Dissociation: A Cadaveric Study

There are many techniques for the treatment of chronic scapholunate dissociation. The three-ligament tenodesis (3LT) is used most widely, but reconstruction of the dorsal ligament alone may not provide sufficient stability. The Mark-Henry technique (MHT) compensates for the insufficient stability of 3LT by additional reconstruction of the volar ligament, but the procedure is complex. The SwiveLock technique (SWT), a recently introduced method, provides stability by using autologous tendons with synthetic tapes, but lacks long-term clinical results. To perform biomechanical comparisons of different reconstructive techniques for scapholunate dissociation using a controlled laboratory cadaveric model. Eleven fresh-frozen upper-extremity cadaveric specimens were prepared. The scapholunate distance, scaphoid rotation, and lunate rotation of the specimens were measured during continuous flexion-extension and ulnar-radial deviation movements. The data were collected using a wrist simulator with a linear guide rail system (tendon load/motion-controlled system) and a motion capture system. Results were compared in five conditions: (1) intact, (2) scapholunate dissociation, (3) SWT, (4) 3LT, and (5) MHT. Paired t-test was employed to compare the biomechanical characteristics of intact wrists to those of scapholunate dissociated wrists, and to those of wrists after each of the three reconstruction methods. SWT and MHT were effective solutions for reducing the widening in scapholunate distance. According to the radioscaphoid angle, all three reconstruction techniques were effective in addressing the flexion deformity of the scaphoid. According to the radiolunate angle, only SWT was effective in addressing the extension deformity of the lunate. In terms of scapholunate angle, only the results after SWT did not differ from those of the intact wrist. The SWT technique most effectively improved distraction intensity and rotational strength for the treatment of scapholunate dissociation. Taking into account the technical complexity of 3LT and MHT, SWT may be a more efficient technique to reduce operating time and minimize complications due to multiple incisions, transosseous tunnels, and complicated shuttling.

Impact of the COVID-19 Pandemic on Adolescent Self-Harm: Based on a National Emergency Department Information System

Republic of Korea's suicide rate is the highest among Organization for Economic Co-operation and Development countries. In Republic of Korea, suicide is the leading cause of death among young people aged 10-19 years. This study aimed to identify changes in patients aged 10-19 years who visited the emergency department in Republic of Korea after inflicting self-harm over the past five years and to compare the situations before and after the outbreak of the COVID-19 pandemic. Analysis of government data revealed that the average daily visits per 100,000 were 6.25, 8.18, 13.26, 15.31, and 15.71 from 2016 to 2020, respectively. The study formed four groups for further analysis, with the population divided by sex and age (10-14 and 15-19 years old). The late-teenage female group showed the sharpest increase and was the only group that continued to increase. A comparison of the figures 10 months before and after the outbreak of the pandemic revealed a statistically significant increase in self-harm attempts by only the late-teenage female group. Meanwhile, visits (per day) in the male group did not increase, but the rates of death and ICU admission increased. Additional studies and preparations that account for age and sex are warranted.

Biomechanical Analysis of Three Different Reconstruction Techniques for Scapholunate Instability: A Cadaveric Study

BACKGROUND

This study aimed to compare the biomechanical strength of 360° scapholunate interosseous ligament (SLIL) reconstruction only using an artificial material (AM), double dorsal limb (DDL) SLIL reconstruction only using AM, and the modified Brunelli technique (MBT) with ligament.

METHODS

Eight cadaver wrists were used for this study. The SL interval, SL angle, and radiolunate (RL) angle were recorded with MicroScribe. The SL distance was measured after dividing the volar and dorsal aspects. We utilized four different wrist postures (neutral, flexion, extension, and clenched fist) to compare five conditions: intact wrist, SLIL resection, 360° SLIL reconstruction using AM, DDL SLIL reconstruction using AM, and MBT SLIL reconstruction with ligament.

RESULTS

The dorsal SL distance in the SLIL resection was widened in all wrist positions. The dorsal SL distance was restored with all three techniques and in all wrist positions. The volar SL distance in the wrist extension position was widened in the SLIL resection condition. The volar SL distance was restored in the extension position after 360° SLIL reconstruction using AM condition. There were no statistically significant differences in SL and RL angles among the conditions.

CONCLUSIONS

All three reconstruction techniques could restore the dorsal SL distance. However, only the 360° SLIL reconstruction using AM restored the volar SL distance in the wrist extension position. DDL SLIL reconstruction using AM tended to overcorrect, whereas 360° SLIL reconstruction using AM effectively stopped volar SL interval widening.

Kinematic analysis of two scapholunate ligament reconstruction techniques

PURPOSE

This study compares the kinematic changes after the procedures for scapholunate interosseous ligament (SLIL) reconstruction-the modified Brunelli technique (MBT) and Mark Henry's technique (MHT).

METHODS

Ten cadaveric wrists were used. The scapholunate (SL) interval and angle and radiolunate (RL) angle were recorded using the MicroScribe system. The SL interval was measured by dividing the volar and dorsal portions. Four motions of the wrist were performed-neutral, flexion, extension, and clenched fist (CF) positions-and compared among five conditions: (1) intact wrist, (2) volar SLIL resection, (3) whole SLIL resection, (4) MBT reconstruction, and (5) MHT reconstruction.

RESULTS

Under the whole SLIL resection condition, the dorsal SL intervals were widened in all positions. In all positions, the dorsal SL intervals were restored after MBT and MHT. The volar SL interval widened in the extension position after volar SLIL resection. The volar SL interval was not restored in the extension position after MBT and MHT. The SL angle increased in the neutral and CF positions under the whole SLIL resection condition. The SL angle was not restored in the neutral and CF positions after MBT and MHT. The RL angle increased in the neutral and CF positions under the whole SLIL resection condition. The RL angle was not restored in the neutral and CF positions after MBT and MHT.

CONCLUSION

The MBT and MHT may restore the dorsal SL interval. No significant differences in restoration of the SL interval between MBT and MHT were found in the cadaveric models.

CLINICAL RELEVANCE

No significant differences between MBT and MHT were found in the cadaveric models for SLIL reconstruction. When considering the complications due to volar incision and additional procedures in MHT, MBT may be a more efficient technique in terms of operative time and injury of the anterior structures during surgery, but further research is needed.

Scapholunate and lunotriquetral interosseous ligament augmentation with internal bracing in perilunate dislocation: Case reports

RATIONALE

The goals of surgical treatment of the perilunate dislocation (PLD) are confirmation of reduction, ligament repair, and supplemental fixation of the bony architecture. Open reduction and direct repair of the torn ligament are recommended for acute PLD. However, repair of the scapholunate interosseous ligament (SLIL) and lunotriquetral interosseous ligament (LTIL) is often unreliable, and secure repair is challenging. Internal bracing (IB) is an augmentation method that uses high-strength non-absorbable tape and enhances strength and support during the critical period of ligamentous healing. However, there is a paucity of data on the application of IB for PLD in the wrist. We report 3 cases of PLD that were augmented with IB after SLIL and LTIL repair.

PATIENT CONCERNS

All 3 cases were men who visited our emergency department with wrist after falling off a ladder.

DIAGNOSES

Initial radiographs revealed a dorsal PLD.

INTERVENTIONS

Surgically, complete rupture of the SLIL and LTIL were confirmed. K-wires were placed into the scaphoid and lunate and used as joysticks to correct the intercalated segment instability pattern. This usually requires correcting scaphoid flexion and lunate extension and closing the scapholunate interval. Prior to SLIL and LTIL repair, temporary intercarpal fixation was performed with K-wires to maintain the carpal relationship. The dorsal SLIL and LTIL were carefully repaired using suture anchors. However, ligament repair was unreliable, and insecure. In view of the likelihood of insufficient repair, we performed IB augmentation using synthetic tape.

OUTCOMES

At the last follow-up, all cases were pain-free and had returned to all activities. The last follow-up radiographs showed good alignment of the carpal bones and no arthritic changes.

LESSONS

IB augmentation can reduce the period of K-wire fixation and cast immobilization and can enable early joint motion. We believe that interosseous ligament augmentation using IB is a reasonable treatment option for PLD.

Sympathetic predominance before tourniquet deflation is associated with a reduction in arterial blood pressure after tourniquet deflation during total knee arthroplasty

High dependency of arterial blood pressure (ABP) on enhanced sympathetic activity, which maintains vascular tone, leads to hypotension after hemodynamic insults that blunt the sympathetic activity. Therefore, we hypothesized that sympathovagal balance before tourniquet deflation (TD) determines the extent of a reduction in ABP after TD during total knee arthroplasty (TKA). Fifty-four hypertensive female patients undergoing TKA under spinal anesthesia were analyzed. The sympathovagal balance [low-to-high frequency ratio of heart rate variability (LF/HF)] before TD was defined as (LF/HF during 5 min before TD-preanesthetic LF/HF)/preanesthetic LF/HF (%). An increase in its value represents a shift in sympathovagal balance toward sympathetic predominance. The percent change in the mean ABP (MAP) after TD was defined as (minimum MAP during 10 min after TD-averaged MAP during 5 min before TD)/averaged MAP during 5 min before TD (%). Simple linear regression was performed to assess the correlation between the sympathovagal balance before TD and change in MAP after TD. The correlation was also assessed by multiple linear regression controlling for age, duration of tourniquet inflation, and spinal anesthesia-induced hypotension. Thirty-two minutes (on average) after tourniquet inflation, the MAP was decreased by 12.1 (-3.0 to 47.9) % [mean (range)] upon TD (P<0.001). The sympathovagal balance before TD was negatively proportional to the change in MAP after TD in both simple and multiple linear regression models (R2=0.323 and 0.340, P<0.001). A shift in sympathovagal balance toward sympathetic predominance before TD is associated with a decrease in ABP after TD.

Biceps Box Configuration for Superior Capsule Reconstruction of the Glenohumeral Joint Decreases Superior Translation but Not to Native Levels in a Biomechanical Study

Purpose

To quantitatively biomechanically assess superior stability, subacromial contact pressures, and glenohumeral kinematics of an in situ biceps tenodesis and a box-shaped long head of the biceps tendon (LHBT) superior capsule reconstruction (SCR) in a superior massive rotator cuff tear (MCT) model.

Methods

Eight cadaveric shoulders (mean age, 62 years; range, 46-70 years) were tested with a custom testing system used to evaluate range of motion, superior translation, and subacromial contact pressure at 0°, 20°, and 40° of abduction. Conditions tested included native state, MCT (complete supraspinatus and one-half of the infraspinatus), a box-shaped LHBT SCR, and an in situ biceps tenodesis. The box-shaped SCR was performed by maintaining the biceps origin, securing 2 corners to the greater tuberosity, and one corner to the posterior glenoid. The in situ tenodesis was performed anatomically at the top of the articular margin in the same shoulder after take-down of the box SCR.

Results

Range of motion was not impaired with either repair construct (P > .05). The box SCR decreased superior translation by approximately 2 mm compared with the MCT at 0°, but translation remained greater compared with the intact state in nearly every testing position. The in situ tenodesis had no effect on superior translation. Peak subacromial contact pressure was increased in the MCT at 0° and 20° abduction compared with the native state but not different between the native and box SCR at the same positions.

Conclusions

A box-shaped SCR using the native biceps tendon partially restores increased superior translation and peak subacromial contact pressure due to MCT. The technique may have a role in augmentation of an irreparable MCT.

Clinical Relevance

The box-shaped LHBT SCR technique may have a role in augmentation of an irreparable MCT.

Biomechanics of tensor fascia lata allograft for superior capsular reconstruction

BACKGROUND

We hypothesized that in a cadaveric massive rotator cuff tear (MCT) model, a fascia lata (FL) allograft superior capsular reconstruction (SCR) would restore subacromial contact pressure and humeral head superior translation without limiting range of motion (ROM). Therefore, the objective of this study was to compare these parameters between an intact rotator cuff, MCT, and allograft FL SCR.

METHODS

Eight fresh cadavers were studied using a custom shoulder testing system. ROM, superior translation, and subacromial contact pressure were measured in each of 3 states: (1) intact rotator cuff, (2) MCT, and (3) MCT with SCR.

RESULTS

Total ROM was increased in the MCT state at 60° of abduction (P = .037). FL SCR did not restrict internal or external rotational ROM. Increased superior translation was observed in the MCT state at 0° and 30° of humeral abduction, with no significant difference between the intact cuff and FL SCR states. The MCT state significantly increased mean subacromial contact pressure at 0° of abduction with 30° and 60° of external rotation, and FL SCR restored this to intact levels. Peak subacromial contact pressure was increased for the MCT state at 0° of abduction with 30° and 60° of external rotation, as well as 30° of abduction with 30° of external rotation.

CONCLUSION

This study demonstrates a tensor FL allograft preparation technique for use in SCR. After MCT, FL SCR restores ROM, superior translation, and subacromial contact pressure to the intact state.

The effectiveness of vitamin D supplementation in functional outcome and quality of life (QoL) of lumbar spinal stenosis (LSS) requiring surgery

Study design

This is a retrospective cohort comparative study.

Background

Vitamin D supplementation is considered to be associated with good functional outcome. Thus, a few studies have proposed vitamin D supplementation is benefit to the functional outcome in LSS requiring surgery. The purpose of this study is to identify the prevalence of vitamin D deficiency in patients with LSS requiring surgery, and to compare the differences between the cases whether vitamin D is supplemented and vitamin D is not supplemented in terms of a QoL during postoperative 2 year.

Methods

All patients with LSS who underwent surgery from March 1, 2015 to August 31, 2016 were enrolled. Among them, 61 patients with vitamin D deficiency were divided into two groups (supplemented group (A) and non-supplemented group (B)). Functional outcomes using Oswestry Disability Index (ODI) and Rolland Morris Disability Index (RMDQ) and QoL using SF-36 were evaluated at 12-month and 24-month follow-up periods. Differences in functional score and SF-36 between the vitamin D supplemented and non-supplemented group were compared.

Results

Among the total 102 patients, 78 patients (76.5%) had vitamin D deficiency. Of the 78 patients, 61 patients were included, 27 patients were group A and 27 patients were group B. There was no difference in age and 25-OHD level between the two groups (all 0 > 0.05). Group A were better functional outcomes at 2 years after surgery (p < 0.05). On the QoL, group A were higher score than group B from 12 month later after surgery (p < 0.05).

Conclusions

Vitamin D deficiency was highly prevalent in LSS patients (76.5%). Assessment of serum 25-hydroxyvitamin D (25(OH)D) is recommended in LSS needing surgical intervention and active treatment vitamin D supplementation and maintenance of normal range should be considered for better postoperative functional outcome and QoL.

The Prevalence of Facet Tropism and Its Correlation with Low Back Pain in Selected Community-Based Populations

Background

The incidence of facet tropism (FT) and its correlation with low back pain (LBP) have, to our knowledge, not yet been investigated among selected community-based populations who visited departments unrelated to LBP with their chief complaints unrelated to LBP. In this study, we aimed to evaluate the prevalence of FT among selected patients in whom LBP was not the chief complaint and the correlation between FT and LBP among these patients.

Methods

Among patients who underwent computed tomography during 2014 for reasons unrelated to LBP, we enrolled 462 patients who satisfied the inclusion and exclusion criteria. The degree of tropism was defined as grade 0, 1, and 2 for FT, FT+, and FT++, respectively. LBP was evaluated using a modified version of the Nordic low back pain questionnaire. For additional evaluation of dynamic LBP, the question, "Did your pain go away when lying down still or standing up straight, and did it also intensify when you bend or stretch your back?," was included in the questionnaire.

Results

The L4-5 intervertebral area was most frequently and severely affected by FT with an incidence rate of 46.3%, and severe FT was observed in 24.7% of the patients. FT increased with age at L2-3 and L5-S1 levels. FT at L2-3 level was correlated with LBP (p = 0.035) and dynamic LBP (p = 0.033). The FT grade at L2-3 level was correlated with dynamic LBP (p = 0.022) but not with LBP (p = 0.077). The relative risk of FT at L2-3 level was 1.614 for LBP and 1.724 for dynamic LBP.

Conclusions

The prevalence of FT among community-based populations was 46.3% and its severe form was more frequently observed at L4-5 level (24.7%). LBP was correlated with FT at L2-3 level. The relative FT-associated risk of LBP was 1.6 at L2-3 level, and the relative L2-3 FT-associated risk of dynamic LBP was 1.724.

Prolonged pain reducing effect of sodium hyaluronate-carboxymethyl cellulose solution in the selective nerve root block (SNRB) of lumbar radiculopathy: a prospective, double-blind, randomized controlled clinical trial

BACKGROUND

The pattern of linear graph schematized by visual analogue scale (VAS) score displaying pain worsening between 2 days and 2 weeks after selective nerve root block (SNRB) is called rebound pain.

PURPOSE

The purpose of this study was to determine if sodium hyaluronate and carboxymethyl cellulose solution (HA-CMC sol) injection could reduce the occurrence of rebound pain at 3 days to 2 weeks after SNRB in patients with radiculopathy compared with injection with corticosteroids and local anesthetics alone.

STUDY DESIGN/SETTING

Double blinded randomized controlled clinical trial.

PATIENT SAMPLE

A total of 44 patients (23 of 24 patients in the Guardix group and 21 of 24 patients in the control group) who finished the follow-up session were subjects of this study.

OUTCOME MEASUREMENT

Patients were asked to write down their average VAS pain scores daily for 12 weeks. Functional outcomes were assessed by Oswestry Disability Index, Roland Morris Disability Questionnaire , and Short Form-36.

METHOD

A cocktail of corticosteroids, 1% lidocaine, 0.5% Bupivacaine, and 1 mL of normal saline was used for the control group whereas a cocktail of corticosteroids, 1% lidocaine, 0.5% Bupivacaine, and 1 mL of HA-CMC solution was used for the G group. Study participants were randomized into one of two treatment regimens. They were followed up for 3 months.

RESULTS

VAS score at 2 weeks after the procedure was 4.19±1.32 in the control group, which was significantly (p<.05) higher than that (2.43±1.24) in the G group. VAS score at 6 weeks after the procedure was 4.00±1.23 in the control group and 3.22±1.45 in the G group, showing no significant (p=.077) difference between the two groups. There were no significant differences in functional outcomes at 6 or 12 weeks after the procedure.

CONCLUSIONS

Compared with conventional cocktail used for SNRB, addition of HA-CMC sol showed effective control of rebound pain at 3 days to 2 weeks after the procedure.

Correlation between Short-Form 36 Scores and Neck Disability Index in Patients Undergoing Anterior Cervical Discectomy and Fusion

STUDY DESIGN

Case control study.

PURPOSE

To determine how the Neck Disability Index (NDI), a cervical spine-specific outcome, reflects health-related quality-of-life, and if NDI is correlated to the 36-item Short-Form Health Survey (SF-36) scores.

OVERVIEW OF LITERATURE

NDI is a useful tool for assessing health-related quality of life in patients with neck pain.

METHODS

We used the Pearson product-moment correlation coefficient to assess the validity of all items under NDI and SF-36, and the Pearson's correlation coefficient to assess the correlation between NDI and total SF-36 scores. The primary outcome measures were spine-specific health status- and general health status-measures after spine surgery, and these were evaluated every year for 2 years, using both NDI and SF-36 scores.

RESULTS

NDI had a strong linear correlation with SF-36 and its two scales, the Physical Component Score (PCS) and the Mental Component Score (MCS), attesting to the validity of these two instruments. Among the eight subscales of SF-36, there was a strong linear correlation between NDI and PCS-physical functioning, PCS-bodily pain, and MCS-role emotional. Further, a moderate linear correlation was observed between NDI and subscales of PCS-role physical, PCS-general health, and MCS-social functioning, and between NDI and MCS-vitality and MCS-mental health.

CONCLUSIONS

Our findings suggest that the NDI adequately reflects the patient's physical and mental quality of life, implying that the use of NDI to assess functional outcomes can also be ultimately used to evaluate the patient's quality of life.

Neutrophil-lymphocyte ratio predicts response to chemotherapy in triple-negative breast cancer

Background

The neutrophil-lymphocyte ratio (nlr) has been reported to correlate with patient outcome in several cancers, including breast cancer. We evaluated whether the nlr can be a predictive factor for pathologic complete response (pcr) after neoadjuvant chemotherapy (nac) in patients with triple-negative breast cancer (tnbc).

Methods

We analyzed the correlation between response to nac and various factors, including the nlr, in 87 patients with tnbc who underwent nac. In addition, we analyzed the association between the nlr and recurrence-free survival (rfs) in patients with tnbc.

Results

Of the 87 patients, 25 (28.7%) achieved a pcr. A high Ki-67 index and a low nlr were significantly associated with pcr. The pcr rate was higher in patients having a high Ki-67 index (≥15%) than in those having a low Ki-67 index (35.7% vs. 0%, p = 0.002) and higher in patients having a low nlr (≤1.7) than in those having a high nlr (42.1% vs. 18.4%, p = 0.018). In multiple logistic analysis, a low nlr remained the only predictive factor for pcr (odds ratio: 4.274; p = 0.008). In the survival analysis, the rfs was significantly higher in the low nlr group than in the high nlr group (5-year rfs rate: 83.7% vs. 66.9%; log-rank p = 0.016).

Conclusions

Our findings that the nlr is a predictor of pcr to nac and also a prognosticator of recurrence suggest an association between response to chemotherapy and inflammation in patients with tnbc. The pretreatment nlr can be a useful predictive and prognostic marker in patients with tnbc scheduled for nac.

Prevalence and Risk Factors of Neuropathic Pain in Patients with a Rotator Cuff Tear

BACKGROUND

Until now, few studies had investigated the neuropathic pain component in patients with a rotator cuff tear (RCT).

OBJECTIVES

The aim of the study was to identify the neuropathic pain component in patients with RCT and to determine the factors correlated with neuropathic pain in patients with RCT.

STUDY DESIGN

Prospective, cohort, prognostic study.

SETTING

Study patients who required arthroscopic rotator cuff repair were analyzed in a hospital setting.

METHODS

We prospectively studied 101 patients who were less than 60 years old with full-thickness tears requiring arthroscopic rotator cuff repair and met the inclusion and exclusion criteria. Multiple regression analysis was performed to identify variables that independently affected neuropathic pain in patients with a RCT. We use Douleur neuropathique 4 questionnaire (DN4) to assess neuropathic pain, which was >/= 4 points of the DN4 questionaire. The visual analog scale (VAS) for the most severe pain within 4 weeks before admission and mean pain level during the last 4 weeks were checked. The atrophy grades of the rotator cuff muscles were classified on magnetic resonance images according to the Goutallier classification. The size and medial retraction of the RCT were measured during arthroscopic repair for RCT.

RESULTS

Sixteen (15.8%) of the 101 patients had neuropathic pain according to the cut-off values on the DN4 questionnaire for diagnosing neuropathic pain. The neuropathic pain group had significantly higher prevalence of smoking (P = 0.042), more mean VAS during last 4 weeks (P = 0.008), larger cuff tear (P = 0.003), more medial retraction of cuff (P = 0.016), and severe fatty degeneration of rotator cuff muscles (supraspinatus, P < 0.001; subscapularis, P < 0.001; and infraspinatus, P = 0.003) than the nonneuropathic pain group. The multiple logistic regression analyses showed that more mean VAS during the last 4 weeks and tear size of a rotator cuff were independent of other factors for the neuropathic pain of the patients with a full-thickness RCT.

LIMITATIONS

Small sample size is the first limitation of this study.

CONCLUSIONS

The prevalence of neuropathic pain in patients with a full-thickness RCT requiring arthroscopic rotator cuff repair was 15.8 % according to the DN4 questionnaire. The neuropathic pain component was more relevant to the severity of pain and tear size in the patients with a full-thickness RCT. It is important to be aware of the existence of neuropathic pain when treating a patient presenting with pain due to a RCT because accompanying neuropathy with a RCT could have a worse effect on repair of a RCT. IRB approval and clinical trial registration number: CR-15-045.

KEY WORDS

Shoulder, rotator cuff tear, arthroscopic rotator cuff repair, neuropathic pain.

Comparison of the Extent of Degeneration among the Normal Disc, Immobilized Disc, and Immobilized Disc with an Endplate Fracture

BACKGROUND

This study attempts to prove a cause and effect relationship between spine immobilization following posterior fixation for unstable burst fractures and degeneration observed following hardware removal.

METHODS

We enrolled 57 patients (259 intervertebral discs [IVDs]) who underwent only posterior instrumentation without fusion for thoracolumbar and lumbar unstable burst fractures. We arbitrarily named the IVD that has an endplate fracture after immobilization using pedicle screws as the fractured endplate and immobilized disc (FEID), the IVD that has no endplate fracture after immobilization using pedicle screws as the nonfractured endplate and immobilized disc (NFEID), and the IVD that has no endplate fracture and no immobilization instrumentation as the normal disc (ND). At 2 years after implant removal, magnetic resonance imaging (MRI) was performed again for comparison. The extent of disc degeneration was classified using the Pfirrmann classification system.

RESULTS

FEIDs were present in 67 levels, NFEIDs in 78 levels, and NDs in 114 levels. According to the Pfirrmann classification, 7.9% of the NDs, 32.1% of the NFEIDs, and 43.3% of the FEIDs were more degenerated at 2 years after implant removal. The FEIDs and NFEIDs were more degenerated than the NDs and the FEIDs were more degenerated than the NFEIDs at statistically significant levels (p < 0.001 for both).

CONCLUSIONS

Spine immobilization with transpedicular screws has a significant influence on disc degeneration, and an endplate fracture accelerates the degeneration process.

Association between basal-like phenotype and BRCA1/2 germline mutations in Korean breast cancer patients

INTRODUCTION

BRCA mutation testing allows index patients and their families to be provided with appropriate cancer risk-reduction strategies. Because of the low prevalence of BRCA mutations in unselected breast cancer patients and the high cost of genetic testing, it is important to identify the subset of women who are likely to carry BRCA mutations. In the present study, we examined the association between BRCA1/2 germline mutations and the immunohistochemical features of breast cancer.

METHODS

In a retrospective review of 498 breast cancer patients who had undergone BRCA testing at Seoul National University Bundang Hospital between July 2003 and September 2012, we gathered immunohistochemical information on estrogen receptor (er), progesterone receptor (pr), her2 (human epidermal growth factor receptor 2), cytokeratin 5/6, egfr (epidermal growth factor receptor), and p53 status.

RESULTS

Among the 411 patients eligible for the study, 50 (12.2%) had germline mutations in BRCA1 or BRCA2. Of the 93 patients with triple-negative breast cancer (tnbc), 25 with BRCA1/2 mutations were identified (BRCA1, 20.4%; BRCA2, 6.5%). On univariate analysis, er, pr, cytokeratin 5/6, egfr, and tnbc were found to be related to BRCA1 mutations, but on multivariate analysis, only tnbc was significantly associated with BRCA1 mutations. Among patients with early-onset breast cancer or with a family history of breast or ovarian cancer, BRCA1 mutations were significantly more prevalent in the tnbc group than in the non-tnbc group.

CONCLUSIONS

In the present study, tnbc was the only independent predictor of BRCA1 mutation in patients at high risk of hereditary breast and ovarian cancers. Other histologic features of basal-like breast cancer did not improve the estimate of BRCA1 mutation risk.

Characteristic of InGaN/GaN Laser Diode Grown by a Multi-Wafer MOCVD System

InGaN/GaN multi-quantum well (MQW) laser diodes (LDs) were grown on c-plane sapphire substrates using a multi-wafer MOCVD system. The threshold current for pulsed lasing was 1.6 A for a gain-guided laser diode with a stripe of 10 × 800 μm2. The threshold current density was 20.3 kA cm−2 and the threshold voltage was 16.5 V. The optical power ratio of transverse electric mode to transverse magnetic mode was found to be greater than 50. The characteristic temperature measured from the plot of threshold current versus measurement temperature was between 130 and 150K.

Effects of a modified live CSFV vaccine on the development of PMWS in pigs infected experimentally with PCV-2

The objective of this study was to determine the effect of vaccination against classical swine fever virus (CSFV) on the development of postweaning multisystemic wasting syndrome (PMWS) in conventional pigs infected experimentally with porcine circovirus type 2 (PCV-2). The pigs infected with PCV-2 and immunised with modified live CSFV developed mild to moderate PMWS, whereas none of the pigs infected with PCV-2 alone or immunised with modified live CSFV alone developed PMWS. Lesions histologically characteristic of PMWS were observed in lymph nodes from the pigs infected with PCV-2 and immunised with modified live CSFV vaccine, and extensive replication of PCV-2 was detected in the nodes by in situ hybridisation.

Efficient taste and odour removal by water treatment plants around the Han River water supply system

Seven major water treatment plants in Seoul Metropolitan Area, which are under Korea Water Resources Corporation (KOWACO)'s management, take water from the Paldang Reservoir in the Han River System for drinking water supply. There are taste and odour (T&O) problems in the finished water because the conventional treatment processes do not efficiently remove the T&O compounds. This study evaluated T&O removal by ozonation, granular activated carbon (GAC) treatment, powder activated carbon (PAC) and an advanced oxidation process in a pilot-scale treatment plant and bench-scale laboratory experiments. During T&O episodes, PAC alone was not adequate, but as a pretreatment together with GAC it could be a useful option. The optimal range of ozone dose was 1 to 2 mg/L at a contact time of 10 min. However, with ozone alone it was difficult to meet the T&O target of 3 TON and 15 ng/L of MIB or geosmin. The GAC adsorption capacity for DOC in the three GAC systems (F/A, GAC and O3 + GAC) at an EBCT of 14 min is mostly exhausted after 9 months. However, substantial TON removal continued for more than 2 years (>90,000 bed volumes). GAC was found to be effective for T&O control and the main removal mechanisms were adsorption capacity and biodegradation.

Variations in the behaviors to novel objects among five inbred strains of mice

Novelty stimuli cause various behavioral responses, such as exploration and avoidance, and contextual variables may contribute to the behavioral outputs. Here, we tried to compare the behavioral responses to novel objects of five inbred strains of mice (C57BL/6J, 129/svJae, C3H/HeJ, BALB/cJ and DBA/2J) by using a modified novel object test where a small light-weight cube wrapped with paper was presented to mice in a home cage without beddings. In response to these objects, the C57BL/6J, 129/svJae and C3H/HeJ mice showed mild exploratory behaviors, such as approaching, sniffing or brief contact. In striking contrast, the BALB/cJ and DBA/2J mice, which have been known to show high avoidance/low exploration in other behavioral paradigms, exhibited play-like secondary reactions toward the objects after initial primary exploratory behaviors. Specifically, DBA/2J mice would move the object around in the cage, holding it with their mouths, and BALB/cJ mice would gnaw the object, eventually stripping off the wrapping paper. Such behaviors decreased when similar objects were presented repeatedly. The present results suggest that active manipulations of novel objects may be a relevant parameter for measuring novelty-induced behaviors in mice and appear to be strongly influenced by genetic factors.

Blockade of p38 mitogen-activated protein kinase pathway inhibits interleukin-6 release and expression in primary neonatal cardiomyocytes

The induction of interleukin-6 (IL-6) using combined proinflammatory agents (LPS/IFN-gamma or TNF-alpha/IFN-gamma) was studied in relation to p38 mitogen-activated protein kinase (MAPK) and NF-kappaB transcriptional factor in primary neonatal cardiomyocytes. When added to cultures of cardiomyocytes, the combined agents (LPS/IFN-gamma or TNF-alpha/IFN-gamma) had stimulatory effect on the production of IL-6 and the elevation was significantly reduced by SB203580, a specific p38 MAPK inhibitor. SB203580 inhibited protein production and gene expression of IL-6 in a concentration-dependent manner. In this study, IFN-gamma enhancement of TNF-alpha-induced NF-kappaB binding affinity as well as p38 MAP kinase activation was observed. However, a specific inhibitor of p38 MAPK, SB203580, had no effect on TNF-alpha/IFN-gamma or LPS/IFN-gamma-induced NF-kappaB activation. This study strongly suggests that these pathways about TNF-alpha/IFN-gamma or LPS/IFN-gamma-activated IL-6 release can be primarily dissociated in primary neonatal cardiomyocytes.

Pyrrolidine dithiocarbamate inhibits serum-induced NF-κB activation and induces apoptosis in ROS 17/2.8 osteoblasts

Nuclear factor-kappaB (NF-kappaB) activity affects cell survival in ROS 17/2.8 osteoblasts. Preventing NF-kappaB transcription activity with a potent NF-kappaB inhibitor, pyrrolidine dithiocarbamate (PDTC), results in apoptosis. Thus, we explored the effect of pyrrolidine dithiocarbamate (PDTC), which potently blocks the activation of nuclear factor-kappaB (NF-kappaB) in serum-exposed condition, on the activation of mitogen activated protein kinase (MAPK), especially, JNK/SAPK and p38 MAPK induction. PDTC transiently increased the phosphotransferase activity of c-Jun N-terminal Kinase1 (JNK1), which might in turn activates transcriptional activity of activating protein-1 (AP-1). The activation of JNK was completely decreased in dominant negative JNK1 transfected cells and the PDTC-induced cell death was attenuated in these cells. In addition, AP-1 activation was decreased in the JNK1 transfected cells, compared with vector-transfected cells. The NF-kappaB inhibitor also transiently activates p38 MAPK but SB203580, a specific p38 MAPK inhibitor, does not have any regulatory effect on PDTC-induced cell death, suggesting that the cell death is mediated by JNK not by p38 MAPK. Thus, overall, these results show that PDTC induces apoptosis and suggest that JNK/SAPK and subsequent AP-1 activation may be involved in the apoptotic pathway in ROS 17/2.8 osteoblasts.

Suppression of the growth/differentiation transition in Dictyostelium development by transient expression of a novel gene, dia1

In Dictyostelium discoideum Ax-2 cells, a specific checkpoint (PS point) from which cells enter the differentiation phase in response to starvation has been specified in the cell cycle. Using the differential display method, we isolated a novel gene, dia1 (differentiation-associated gene 1), that is specifically expressed in cells differentiating from the PS point. The dia1 mRNA has an open reading frame of 1,368 bp and is deduced to code for a 48.6 kDa protein (DIA1). The DIA1 protein is highly serine-rich and the serine residues are predominantly located in the C-terminal region. After the PSORT II search, the protein is predicted to be GPI-anchored at the plasma membrane. Unexpectedly, dia1 overexpression rather impaired the progression of differentiation, possibly coupled with the reduced expression of early genes such as cAMP receptor1 (car1). The inhibitory effect of dia1 expression on early differentiation was almost completely nullified by externally applied cAMP pulses. In contrast to dia1 overexpression, antisense RNA-mediated dia1 inactivation was found to enhance the initial step of cell differentiation, as exemplified by precocious expression of car1 and other early genes. We discuss the unique structure and function of DIA1 in relation to the cooperative development of cells during the establishment of multicellular organization.

An antigen reacting with das-1 monoclonal antibody is ontogenically regulated in diverse organs including liver and indicates sharing of developmental mechanisms among cell lineages

The monoclonal antibody designated mAb Das-1, which was generated against a colon epithelial protein, reacts with the normal biliary epithelium and keratinocytes, which are among targets of tissue injury in ulcerative colitis. Moreover, mAb Das-1 reacts with abnormal cells in Barrett's esophagus and chronic cystitis profunda, as well as so-called 'oval cells' in the adult liver, which are considered oncogenic progenitor cells. To establish ontogenic regulation of mAb Das-1 reactivity, we studied 7- to 24-week-old human fetuses by immunohistochemistry. In liver, mAb Das-1 reactivity was further correlated with glycogen, dipeptidyl peptidase IV, glucose-6-phosphatase and gamma-glutamyl transpeptidase expression. mAb Das-1 reacted with cells in organs arising from the pharyngeal cleft (thymus), primitive gut (oral cavity, pharynx, lung, esophagus, stomach, biliary tree, pancreas, liver, colon), ureteric bud (renal tubules, collecting duct), mesonephros (kidney, testis), mesoderm (muscle) and elsewhere (skin, adrenal cortex). In distinction from the adult liver, mAb Das-1 staining was more pronounced in hepatoblasts compared with biliary cells. In adult tissues, however, mAb Das-1 reactivity was restricted to the colon, biliary epithelium, keratinocytes, and ciliary body. These data indicated that the mAb Das-1 recognized epitopes in fetal cells of diverse ectodermal, mesodermal and endodermal origin, compatible with sharing of lineage mechanisms in tissues. Reactivation of mAb Das-1 staining in epithelial precancerous conditions, including carcinomas arising in these organs, is compatible with oncofetal regulation of the antigen, which will facilitate analysis of cell subpopulations during organ development, regeneration and oncogenesis.

Analysis of the C-terminal region of Arabidopsis thaliana APETALA1 as a transcription activation domain

APETALA1 (AP1) of Arabidopsis thaliana is a transcription factor controlling flower development. AP2 is a member of the MADS (MCM1, AGAMOUS, DEFICIENS, SRF) superfamily, which plays important roles in differentiation in plants and animals. MADS domains, which function most importantly in DNA binding, are found in all major eukaryotic kingdoms. In plants, MADS domain-containing proteins also possess a region of moderate sequence similarity named the K domain, which is involved in protein-protein interaction. Little is known about the function of a third, highly variable, domain designated the C domain, as it resides at the C terminus of the MADS proteins of plants. Here we report that the C-terminal domain of Arabidopsis thaliana AP1 and its homologues perform a transcriptional activation function. The C-terminal region of AP1 is composed of at least two separable transcriptional activation domains that function synergistically.

Analysis of the C-terminal region of Arabidopsis thaliana APETALA1 as a transcription activation domain

APETALA1 (AP1) of Arabidopsis thaliana is a transcription factor controlling flower development. AP2 is a member of the MADS (MCM1, AGAMOUS, DEFICIENS, SRF) superfamily, which plays important roles in differentiation in plants and animals. MADS domains, which function most importantly in DNA binding, are found in all major eukaryotic kingdoms. In plants, MADS domain-containing proteins also possess a region of moderate sequence similarity named the K domain, which is involved in protein-protein interaction. Little is known about the function of a third, highly variable, domain designated the C domain, as it resides at the C terminus of the MADS proteins of plants. Here we report that the C-terminal domain of Arabidopsis thaliana AP1 and its homologues perform a transcriptional activation function. The C-terminal region of AP1 is composed of at least two separable transcriptional activation domains that function synergistically.

Expressed sequence tags of radish flower buds and characterization of a CONSTANS LIKE 1 gene

Expressed sequence tag (EST) analysis was conducted for young flower buds of radish plants. Among a total of 66 ESTs examined, 40 showed a significant similarity to previously identified genes. Twenty-eight ESTs were similar to proteins identified in other plants, 11 were similar to eukaryotic proteins other than plants, and one was similar to a prokaryotic protein. Four clones were selected for further studies. EST clone 81, which showed a homology to germin-like proteins was expressed more abundantly in leaves and roots as compared to flower buds. Clone 105 was highly homologous to the translation inhibitor protein and was expressed in all three organs, but the expression level was higher in flower buds and roots. Another EST clone, 133, which shared a significant similarity with the Ran-binding protein, hybridized to two different size transcripts that were detectable only in flower buds. Clone 39 was a homolog of CONSTANS, which is a gene involved in controlling the flowering time in Arabidopsis. The cDNA clone of EST clone 39 containing the entire open reading frame was obtained and designated as RsCOL1 (Raphanus sativus CONSTANS LIKE 1). It was 1049 bp long and contained an open reading frame of 307 amino acid residues (calculated molecular mass = 33.1 kDa). The RsCOL1 protein contained two putative zinc finger motifs in the amino terminal region which were 59% identical to the corresponding region of the Arabidopsis CO protein. The radish protein also contained a predicted nuclear localization domain in the carboxyl terminal region which was 87% identical to the corresponding region of CO. DNA blot analysis revealed that the radish genome contained several genes similar to RsCOL1. RNA blot analysis showed that RsCOL1 was strongly expressed in flower buds at the early bolting stage, and the expression level declined as the flower bud matured. The transcript was also detectable in leaves and roots. In mature flowers, the RsCOL1 transcript was present primarily in carpels.

Controlling the judge variable in grading essay-type items: an application of Rasch analyses to the recruitment exam for Korean public school teachers

The purpose of this paper is to show how the Rasch measurement model can be used to control the effects of judge variable on the grading of essay-type items in the recruitment test for Korean teachers. Special attention is given to two aspects of judges' involvement in the grading. One is to identify a way to minimize the variation of grading due to judge severity. The other concern is to figure out a way to reduce the number of judges without threatening objectivity of ability estimates. Results from the FACETS analyses tell us not only how much grading standards vary among judges and how to adjust them but also it produces comparably reliable ability estimates with fewer judges.

Cloning and sequence analysis of the cDNA encoding the elongation factor-1 beta of Dictyostelium discoideum

A cDNA encoding elongation factor-1 beta (DdEF-1 beta) for protein synthesis was isolated from Dictyostlium discoideum cells by the differential display (DD) method. The DdEF-1 beta cDNA sequence with a length of 733 bp encodes a protein (M(r) 24.1 kDa) consisting of 214 amino acids. Comparison of the predicted amino acid sequence revealed relatively high homology to that of DdEF-1 beta from silkworm (59%), human (57%) and Xenopus (55%). Northern analysis showed that the DdEF-1 beta mRNA is maximally expressed during the vegetative growth phase, followed by marked decrease in response to cell differentiation induced by starvation.

Uvula-nodulus and gravity direction (a study on vertical optokinetic-oculomotor functions)

Some characteristics of vertical optokinetic nystagmus and after-nystagmus, in particular, its up/down gain asymmetry, are known to be influenced by gravity direction, which is basically perceived by otolith organs. However, how such an information of gravity direction is processed within the central nervous system is not well understood, even though the role of cerebellar uvula and nodulus in vertical eye movements has been identified for some time. Accordingly, in this study, vertical optokinetic nystagmus and after-nystagmus were studied in squirrel monkeys both in the upright and side-lateral positions (different gravity direction to the head), before and after uvulonodulectomy. When the optokinetic stimulus was given, the slow phase eye velocity of optokinetic nystagmus was significantly higher in the side-lateral position than that obtained in the upright position. This difference disappeared after uvulonodulectomy. When the initial slow phase eye velocity of optokinetic after-nystagmus was compared, the one obtained in the side-lateral position was significantly higher than that acquired in the upright position. This difference also disappeared after the uvulonodular ablation. Thus, in this study of vertical optokinetic nystagmus and after-nystagmus, the role of uvula and nodulus in relaying the information of gravity direction was confirmed.

Lymphoid development in mice congenitally lacking T cell receptor alpha beta-expressing cells

Vertebrate T cells express either an alpha beta or gamma delta T cell receptor (TCR). The developmental relatedness of the two cell types is unresolved. alpha beta + T cells respond to specific pathogens by collaborating with immunoglobulin-producing B cells in distinct lymphoid organs such as the spleen and Peyer's patches. The precise influence of alpha beta + T cells on B cell development is poorly understood. To investigate the developmental effects of alpha beta + T cells on B cells and gamma delta + T cells, mice homozygous for a disrupted TCR alpha gene were generated. The homozygotes showed elimination of alpha beta + T cells and the loss of thymic medullae. Despite this, gamma delta + T cells developed in normal numbers, and there was an increase in splenic B cells.

Compensation of vertical vestibulo-ocular functions in squirrel monkeys after unilateral labyrinthectomy

Modifications in the vertical vestibulo-ocular reflex (VVOR) were studied in four squirrel monkeys (Saimiri sciureus) over time after unilateral labyrinthectomy. In the dark, with head upright, animals were exposed to sinusoidal rotation in the pitch plane. The magnetic field-pericorneal search coli technique was used to detect eye movement. The upward and downward slow-phase eye velocity (SPEV) of the VVOR and the maximum SPEV of the vertical component of spontaneous nystagmus (SPN) were studied. The mean preoperative gain of VVOR was symmetric. After unilateral labyrinthectomy, the maximum reduction of VVOR gain showed an asymmetry. The recovery of VVOR gain to the preoperative level took about 2 weeks, and the vertical component of SPN was present for about 3 weeks.