Diagnosis of Mycobacterium tuberculosis using palladium-platinum bimetallic nanoparticles combined with paper-based analytical devices

In this study, we demonstrate that palladium-platinum bimetallic nanoparticles (Pd@Pt NPs) as the nanozyme, combined with a multi-layer paper-based analytical device and DNA hybridization, can successfully detect Mycobacterium tuberculosis. This nanozyme has peroxidase-like properties, which can increase the oxidation rate of the substrate. Compared with horseradish peroxidase, which is widely used in traditional detection, the Michaelis constants of Pd@Pt NPs are fourteen and seventeen times lower than those for 3,3',5,5'-tetramethylbenzidine and H2O2, respectively. To verify the catalytic efficiency of Pd@Pt NPs, this study will execute molecular diagnosis of Mycobacterium tuberculosis. We chose the IS6110 fragment as the target DNA and divided the complementary sequences into the capture DNA and reporter DNA. They were modified on paper and Pd@Pt NPs, respectively, to detect Mycobacterium tuberculosis on a paper-based analytical device. With the above-mentioned method, we can detect target DNA within 15 minutes with a linear range between 0.75 and 10 nM, and a detection limit of 0.216 nM. These results demonstrate that the proposed platform (a DNA-nanozyme integrated paper-based analytical device, dnPAD) can provide sensitive and on-site infection prognosis in areas with insufficient medical resources.

The impact of over-distraction on adjacent segment pathology and cage subsidence in anterior cervical discectomy and fusion

Over-distraction has been shown to be a risk factor for cage subsidence and postoperative neck pain after anterior cervical discectomy and fusion (ACDF). Biomechanical studies have demonstrated increased adjacent segment intradiscal pressure after ACDF. The purpose of this study is to determine if over-distraction of the index disc has an effect on adjacent segment pathology. A consecutive series of 145 patients who received primary ACDF for cervical degenerative pathologies from January 2010 to December 2017 were retrospectively reviewed. The patients were divided into: (1) Over-distraction group (postoperative-preoperative index disc height ≥ 2 mm), and (2) No-distraction group (postoperative-preoperative index disc height < 2 mm). Outcome measures included radiographic parameters, Japanese Orthopaedic Association (JOA) score, and incidences of cage subsidence, radiological and clinical adjacent segment pathologies (RASP and CASP) were compared between the two groups preoperatively, postoperatively, and at the final follow-up. The two groups were comparable with respect to age, follow-up length, JOA score, incidence of CASP, and radiographic parameters. The Over-distraction group (83 patients; 115 levels) had smaller preoperative index disc height (4.5 vs. 5.2 mm, p < 0.001), but taller postoperative index disc height (7.7 vs. 6.6 mm, p < 0.001) than No-distraction group (62 patients; 90 levels) Furthermore, significantly higher incidences of cage subsidence (47% vs. 31%, p = 0.04) and RASP (any progression: 48% vs. 15%, p < 0.001; progress ≥ 2 grades: 25% vs. 7%, p = 0.001) were observed in the Over-distraction group. The multivariate analysis indicated that over-distraction and multilevel fusion were independent risk factors for RASP. There were no clinical outcome differences between the Over-distraction group and the No-distraction group in ACDF. Over-distraction of the index level of ≥ 2 mm should be avoided because it significantly increases the incidences of RASP and cage subsidence.

A flash signal amplification approach for ultrasensitive and rapid detection of single nucleotide polymorphisms in tuberculosis

In recent years, the demand for rapid, sensitive, and simple methods for diagnosing deoxyribonucleic acid (DNA) has grown due to the increase in the variation of infectious diseases. This work aimed to develop a flash signal amplification method coupled with electrochemical detection for polymerase chain reaction (PCR)-free tuberculosis (TB) molecular diagnosis. We exploited the slightly miscible properties of butanol and water to instantly concentrate a capture probe DNA, a single-stranded mismatch DNA, and gold nanoparticles (AuNPs) to a small volume to reduce the diffusion and reaction time in the solution. In addition, the electrochemical signal was enhanced once two strands of DNA were hybridized and bound to the surface of the gold nanoparticle at an ultra-high density. To eliminate non-specific adsorption and identify mismatched DNA, the self-assembled monolayers (SAMs) and Muts proteins were sequentially modified on the working electrode. This sensitive and specific approach can detect as low as attomolar levels of DNA targets (18 aM) and is successfully applied to detecting tuberculosis-associated single nucleotide polymorphisms (SNPs) in synovial fluid. More importantly, as this biosensing strategy can amplify the signal in only a few seconds, it possesses a great potential for point-of-care and molecular diagnosis applications.

Music Box-Inspired Semi-Automatic Hematocrit Validation Device

A high hematocrit (HCT) level is strongly associated with the risk of cardiovascular disease. For early diagnosis of cardiovascular disease, it is vital to regularly measure the HCT, which is typically achieved by centrifuging a blood sample to measure the percentage of red blood cells. However, the centrifugal modalities are usually bulky, expensive, and require a stable electric input, which restrict the availability. This research develops a semi-automatic and portable centrifugal device for HCT measurement. This torque-actuated semi-automatic centrifuge, which we call the tFuge, is inspired by a music box, allowing different operators to generate the same rhythm. It is electricity-free and can be controlled based on a constant torque mechanism. Repeatable test results can be received from among different users regardless of their age, sex, and activity. With the assistance of the Boycott effect on the tFuge, we proved that the HCT level is in high linearity to the length of the sedimentation of the blood cells in a tube (R2 = 0.99, sample HCT range 10-60%). The tFuge takes less than 4 min and requires no more than 10 μL of blood that can be obtained by a less-invasive finger prick to complete the testing procedure. Calibrated gradient numbers are printed onto the rotation disc for instant HCT results that can be read by the naked eye. We expect this proposed point-of-care testing device possesses the potential to replace the microhematocrit centrifuge in the regions with limited resources.

The influence of over-distraction on biomechanical response of cervical spine post anterior interbody fusion: a comprehensive finite element study

Introduction: Anterior cervical discectomy and fusion (ACDF) has been considered as the gold standard surgical treatment for cervical degenerative pathologies. Some surgeons tend to use larger-sized interbody cages during ACDF to restore the index intervertebral disc height, hence, this study evaluated the effect of larger-sized interbody cages on the cervical spine with ACDF under both static and cyclic loading. Method: Twenty pre-operative personalized poro-hyperelastic finite element (FE) models were developed. ACDF post-operative models were then constructed and four clinical scenarios (i.e., 1) No-distraction; 2) 1 mm distraction; 3) 2 mm distraction; and 4) 3 mm distraction) were predicted for each patient. The biomechanical responses at adjacent spinal levels were studied subject to static and cyclic loading. Non-parametric Friedman statistical comparative tests were performed and the p values less than 0.05 were reflected as significant. Results: The calculated intersegmental range of motion (ROM) and intradiscal pressure (IDP) from 20 pre-operative FE models were within the overall ranges compared to the available data from literature. Under static loading, greater ROM, IDP, facet joint force (FJF) values were detected post ACDF, as compared with pre-op. Over-distraction induced significantly higher IDP and FJF in both upper and lower adjacent levels in extension. Higher annulus fibrosus stress and strain values, and increased disc height and fluid loss at the adjacent levels were observed in ACDF group which significantly increased for over-distraction groups. Discussion: it was concluded that using larger-sized interbody cages (the height of ≥2 mm of the index disc height) can result in remarkable variations in biomechanical responses of adjacent levels, which may indicate as risk factor for adjacent segment disease. The results of this comprehensive FE investigation using personalized modeling technique highlight the importance of selecting the appropriate height of interbody cage in ACDF surgery.

Quantitative lateral flow immunoassay for rapid detection of procollagen type I N-terminal propeptide in the monitoring of osteoporosis treatment

Appropriate follow-up after treatment initiation in patients with osteoporosis is challenging. Serum biomarkers may offer more efficient monitoring of bone mineral density (BMD) than the currently used dual X-ray absorptiometry; however, significant changes in BMD often occur over at least 12 months. During teriparatide treatment for osteoporosis, monitoring with markers such as procollagen type I propeptide (PINP), which is derived from osteoblasts, can provide clinically useful information for disease management. However, rapid and cost-effective methods for detecting serum PINP are lacking, necessitating a point-of-care test (POCT) for enhanced follow-up efficiency in osteoporosis management. For the quantitative detection of PINP, we developed a high-sensitivity lateral flow immunoassay with a stacking pad (sLFIA). We established a calibration equation based on the test line/control line ratio obtained from our PINP sLFIA results of various nonspiked serum samples to calculate the PINP concentrations in 40 serum samples and compared the result with those obtained using a fully automated electrochemiluminescence immunoassay. PINP concentrations between these two methods exhibited excellent correlation (R = 0.991). In addition, we assessed the serum PINP concentrations of patients with osteoporosis treated with teriparatide. At the 3-month follow-up, their PINP levels were nearly twice as high as those at baseline, thus implying that our method can be used for osteoporosis treatment monitoring. Our findings thus indicate that the PINP sLFIA can serve as a POCT for monitoring medication response and managing osteoporosis.

The surgical outcome of multilevel anterior cervical discectomy and fusion in myelopathic elderly and younger patients

The elderly population has an increased risk of degenerative cervical myelopathy due to multilevel disease, causing motor and sensory dysfunctions and a poor quality of life. Multilevel anterior cervical discectomy and fusion (ACDF) is an alternative surgical treatment option, but has a perceived higher risk of complications. The goal of this study is to report the outcome. We retrospectively reviewed patients from 2006 to 2019 undergoing multilevel ACDF for degenerative cervical myelopathy and compared outcomes and complications between elder patients (aged 70 and above) and younger patients (below 70). The patients' comorbidities, and postoperative complications, radiographic parameters such as C2-C7 Cobb angle, C2-C7 sagittal vertical axis, inter-body height of surgical levels and fusion rate were recorded. Japanese Orthopaedic Association (JOA) score and modified Odom's score were collected. Included were 18 elderly (mean age 74, range 70-87) and 45 young patients (mean age 56, range 43-65) with a follow-up of 43.8 and 55.5 months respectively. Three-level ACDF was the most common. The ratios of ASA class III patients were 94.4% and 48.9% (p < 0.001). The Charlson comorbidity indexes were 4.3 ± 1.03 and 2.1 ± 1.11 (p < 0.001). The average lengths of hospital stays were 4.9 and 4.6 days. Eleven patients (61.1%) in the elderly group experienced at least one short-term complication, compared with 16 patients (35.6%) in the younger group (p < 0.05). The middle-term complications were comparable (22.2% and 20.0%). The JOA score, recovery rate and modified Odom score showed comparable result between groups. Despite its extensiveness, multilevel ACDF is feasible for the elder patients with good clinical outcome and fusion rate. When compared to younger cohort, there is a trend of lower preoperative JOA score and recovery rate. The short-term complication rate is higher in the elderly group.

Better Functional Outcome and Pain Relief in the Far-Lateral-Outside-in Percutaneous Endoscopic Transforaminal Discectomy

Background

Even though percutaneous endoscopic transforaminal discectomy (PETD) has been widely used for the surgical treatment of lumbar herniated disc, there are only a few studies directly comparing the clinical outcomes between microdiscectomy (MD) and PETD. Therefore, further studies are needed in order to compare the clinical outcomes between PETD and MD on a single level more thoroughly.

Methods

We proposed a far-lateral-outside-in technique for PETD to get an entry point without complex planning and facet violation. From September 2017 to September 2019, a total of 155 patients (69 with PETD and 86 with MD) were enrolled for this retrospective study, with the inclusion criteria: single level between L2 and S1, clinical sciatica for at least 6 weeks, and failed attempts with non-surgical treatments. Patients were excluded due to cauda equina syndrome, progressive neurologic deficits, history of lumbar spinal surgery, endplate modic changes, severe disc degeneration and less than 24 months of follow-up.

Results

PETD showed significantly shorter surgery time and less intraoperative blood loss compared to MD. The difference between PETD and MD in VAS back pain (but not VAS leg pain) at follow-up time was significant. The ODI improvement in the follow-up time of 6 months between the 2 groups showed a significant difference (PETD: 31.23±6.59, MD: 39.85±7.81, p < 0.001). MD had a significantly higher chance of postoperative wound infection and poor healing, while PETD was more likely to have recurrence of the herniated disc.

Conclusion

MD has been the gold standard procedure for LDH. However, with the advanced endoscopic technology and surgical technique, PETD has emerged as an alternative method due to higher functional outcome and less wound problems.

Percutaneous Endoscopic Interbody Debridement and Fusion for Pyogenic Lumbar Spondylodiskitis: Surgical Technique and the Comparison With Percutaneous Endoscopic Drainage and Debridement

Objective

Surgical treatment of severe infectious spondylodiskitis remains challenging. Although minimally invasive percutaneous endoscopic drainage and debridement (PEDD) may yield good results in complicated cases, outcomes of patients with extensive structural damage and mechanical instability may be unsatisfactory. To address severe infectious spondylodiskitis, we have developed a surgical technique called percutaneous endoscopic interbody debridement and fusion (PEIDF), which comprises endoscopic debridement, bonegraft interbody fusion, and percutaneous posterior instrumentation.

Methods

Outcomes of PEIDF in 12 patients and PEDD in 15 patients with infectious spondylodiskitis from April 2014 to July 2018 were reviewed retrospectively. Outcome were compared between 2 kinds of surgical procedures.

Results

Patients in PEIDF group had significantly lower rate of revision surgery (8.3% vs. 58.3%), better kyphosis angle (-5.73°±8.74 vs. 1.07°±2.70 in postoperative; 7.09°±7.23 vs. 0.79°±4.08 in kyphosis correction at 1 year), and higher fusion rate (83.3% vs. 46.7%) than those who received PEDD.

Conclusion

PEIDF is an effective approach for treating infectious spondylodiskitis, especially in patients with spinal instability and multiple medical comorbidities.

Self-assisted wound healing using piezoelectric and triboelectric nanogenerators

The complex process of wound healing depends on the coordinated interaction between various immunological and biological systems, which can be aided by technology. This present review provides a broad overview of the medical applications of piezoelectric and triboelectric nanogenerators, focusing on their role in the development of wound healing technology. Based on the finding that the damaged epithelial layer of the wound generates an endogenous bioelectric field to regulate the wound healing process, development of technological device for providing an exogenous electric field has therefore been paid attention. Authors of this review focus on the design and application of piezoelectric and triboelectric materials to manufacture self-powered nanogenerators, and conclude with an outlook on the current challenges and future potential in meeting medical needs and commercialization.

Minimal invasive fixation following with radiotherapy for radiosensitive unstable metastatic spine

BACKGROUND

Minimally invasive surgery (MIS) has become a feasible option for patients with spinal metastasis, but the effectiveness of percutaneous pedicle screw fixation (PPSF) without decompression in patients with severe cord compression remains unknown. We compared PPSF without decompression with debulking surgery in patients with radiosensitive, unstable, metastatic thoracolumbar spinal cord compression.

METHODS

A retrospective study of surgically treated spinal metastasis and spinal cord compression patients was conducted between October 2014 and June 2019. Demographic and pre- and postoperative data were collected and compared between patients treated with minimally invasive percutaneous fixation and external beam radiotherapy (EBRT) (the PPSF group) and those treated with debulking surgery (the debulking group).

RESULTS

We included 50 patients in this study. The PPSF group had a significantly shorter operative time (143.56 ± 49.44 min vs. 181.47 ± 40.77 min; p < .01), significantly lower blood loss (116.67 ± 109.92 mL vs. 696.55 ± 519.43 mL; p < .01), and significantly shorter hospital stay (11.90 ± 9.69 vs. 25.35 ± 20.65; p <0.01) than did the debulking group. No significant differences were observed between the groups in age, sex, spinal instability neoplastic score, ESCC, Tomita scores, numeric rating scale scores, American Spinal Injury Association Impairment Scale scores, survival rates, and complication rates. Postoperative neurologic function and decrease in pain were similar between the groups.

CONCLUSION

The PPSF group had a shorter operation time, shorter length of hospital stay, and less blood loss than did the debulking group. PPSF followed by EBRT is pain relieving, relatively safe and appropriate as palliative therapy.

Paper-based analytical devices for point-of-care blood tests

Blood can be a window to health, and as a result, is the most intensively studied human biofluid. Blood tests can diagnose diseases, monitor therapeutic drugs, and provide information about the health of an individual. Rapid response blood tests are becoming increasingly essential, especially when subsequent treatment is required. Toward this need, paper-based devices have been excellent tools for performing blood tests due to their ability to conduct rapid and low-cost diagnostics and analyses in a non-laboratory environment. In this Perspective, we review recent advances in paper-based blood tests, particularly focusing on the specific techniques and assays applied. Additionally, we discuss the future of these paper-based devices, such as how the signal intensity can be enhanced and how the in situ synthesis of nanomaterials can be used to improve the sensitivity, functionality, and operational simplicity. With these advances, paper-based devices are becoming increasingly valuable tools for point-of-care blood tests in various practical scenarios.

The comparison between anterior and posterior approaches for removal of infected lumbar interbody cages and a proposal regarding the use of endoscope-assisted technique

Background

In cases of postoperative deep wound infection after interbody fusion with cages, it is often difficult to decide whether to preserve or remove the cages, and there is no consensus on the optimal approach for removing cages. The aim of this study was to investigate the surgical management of cage infection after lumbar interbody fusion.

Methods

A retrospective study was conducted between January 2012 and August 2018. Patients were included if they had postoperative deep wound infection and required cage removal. Clinical outcomes, including operative parameters, visual analog scale, neurologic status, and fusion status, were assessed and compared between anterior and posterior approaches for cage removal.

Results

Of 130 patients who developed postoperative infection and required surgical debridement, 25 (27 levels) were diagnosed with cage infection. Twelve underwent an anterior approach, while 13 underwent cage removal with a posterior approach. Significant differences were observed between the anterior and posterior approaches in elapsed time to the diagnosis of cage infection, operative time, and hospital stay. All patients had better or stationary American Spinal Injury Association impairment scale, but one case of recurrence in adjacent disc 3 months after the surgery.

Conclusions

Both anterior and posterior approaches for cage removal, followed by interbody debridement and fusion with bone grafts, were feasible methods and offered promising results. An anterior approach often requires an additional extension of posterior instrumentation due to the high incidence of concurrent pedicle screw loosening. The use of an endoscope-assisted technique is suggested to facilitate safe removal of cages.

A Retrospective Analysis in 1347 Patients Undergoing Cement Augmentation for Osteoporotic Vertebral Compression Fracture: Is the Sandwich Vertebra at a Higher Risk of Further Fracture?

BACKGROUND

Multiple percutaneous vertebral cement augmentation may create sandwich vertebrae. Whether the sandwich vertebra is at higher risk of further fracture remains unknown.

OBJECTIVE

To compare the incidence of further fractures of sandwich vertebrae and adjacent vertebrae and to identify potential risk factors for sandwich vertebral fractures.

METHODS

Patients who underwent cement augmentation for osteoporotic vertebral compression fractures (OVCFs) in a single medical center between January 2012 and December 2015 were included. A sandwich vertebra was defined as an intact vertebra located between 2 previously cemented vertebrae. Demographic data and imaging findings were recorded. All patients were followed up for at least 24 mo postoperatively. During follow-up period, if the patient reported new-onset back pain with corresponding imaging findings, a diagnosis of sandwich vertebral fracture was made.

RESULTS

Among the 1347 patients who underwent vertebroplasty/kyphoplasty for OVCFs, 127 patients with 128 fracture levels met the criteria for sandwich vertebrae (females/males 100/27, mean age 77.8 ± 7.7 yr old). The fracture location was most common in the thoraco-lumbar junction (T10-L2), 68.5% (87/127). The incidence of sandwich vertebral fracture was 21.3%, whereas the incidence of adjacent level fracture of those with no sandwich vertebra was 16.4% (196/1194), P = .1879.

CONCLUSION

The incidence of sandwich vertebral fracture is not higher than that at the adjacent levels. The factor associated with further sandwich vertebral fracture was male gender. Once sandwich vertebral fracture occurred, patients may seek more surgical intervention than those with only adjacent fractures.

Minimally Invasive Surgery Combining Cortical Bone Trajectory Screws and Pedicle Screws to Treat Spondylodiskitis: Technical Notes and Preliminary Results

OBJECTIVE

Various surgical techniques for treating spondylodiskitis have been proposed, but the most appropriate surgical treatment remains controversial. In this study, we propose a new hybrid approach combining the use of cortical bone trajectory screws and pedicle screws with the technique of transforaminal lumbar interbody debridement and fusion. With this method, we can shorten the length of the segment that needs to be fixed, minimize the extent of surgical dissection, and reduce the risk of adjacent level degeneration.

METHODS

Patients with clinical and radiographic evidences of single-level lumbar spondylodiskitis seen between January and December of 2017 were included in the study. Demographic data, including age and sex, were recorded. The intraoperative details, results of culture, functional outcome, radiologic outcome, and length of hospital stay were recorded.

RESULTS

The mean age of 15 patients was 62.8 years. The mean operative time was 135 minutes, and the mean blood loss was 260 mL. The culture rate was 80%. The mean Numeric Rating Scale score and Oswestry Disability Index score significantly improved from 6.60 to 2.47 and from 21.20 to 10.20, respectively. No major perioperative complications occurred.

CONCLUSIONS

With the proposed hybrid approach using cortical bone trajectory and pedicle screws with the transforaminal lumbar interbody debridement and fusion technique, the damaged anterior column can be debrided and reconstructed, and spinal stabilization can also be achieved.

Risk factors of neurological deficit and pulmonary cement embolism after percutaneous vertebroplasty

Background

The risk factors, incidence, and clinical management of pulmonary cement embolism and neurological deficit during percutaneous vertebroplasty (PVP) were evaluated.

Methods

Three thousand one hundred and seventy-five patients with symptomatic osteoporotic vertebral compression fractures (OVCFs) treated with PVP were retrospectively reviewed in a single institution. Clinical parameters such as age, gender, number of fractures, and time from fracture to vertebroplasty were recorded at the time of surgery. Image and surgical parameters including the amount of cement, the vertebral level, uni- or bipedicle surgical approach, and leakage pattern were recorded.

Results

Type-C leakage, including paraspinal (25%), intradiscal (26%), and posterior (0.7%) leakage, was more common than type-B (11.4%) and type-S leaks (4.9%). Cement leakage into the spinal canal (type-C posterior) occurred in 26 patients (0.7%), and four patients needed surgical decompression. Three in nine patients with leakage into thoracic spine needed decompressive surgery, but only one of 17 patients into lumbar spine needed surgery (p < 0.01). Age, gender, number of fractures, and time from fracture to vertebroplasty were not risk factors of pulmonary cement embolism or neurological deficit. The risk factor of pulmonary cement embolism was higher volume of PMMA injected (p < 0.001) and risk factor of neurological deficit was type-C posterior cement leakage into thoracic spine. The incidence of pulmonary cement embolism was significantly high in the volume of PMMA injected (PMMA injection < 3.5 cc: 0%; 3.5–7.0 cc: 0.11%; > 7.0 cc: 0.9%; p < 0.01) which needed postoperative oxygen support.

Conclusions

Cement leakage is relatively common but mostly of no clinical significance. Percutaneous vertebroplasty in thoracic spine and high amount of PMMA injected should be treated with caution in clinical practice.

Surgical outcomes in thoracolumbar fractures with pure conus medullaris syndrome

Background

Pure conus medullaris syndrome is defined as a combination of signs and symptoms of bladder/bowel incontinence and impotence without the presence of lower limbs weakness. The purpose of the study is to assess the recovery of voiding, sexual, and sensory function in patients with isolated conus medullaris syndrome after surgical treatments.

Methods

From January 2005 to December 2012, patients with a single level burst fracture with pure conus medullaris syndrome were assessed. Level of injury, use of steroid, surgical time, surgical approach, preoperative radiographic parameters, and types of neurogenic bladder were recorded. Bladder function was evaluated using urodynamic study; sexual function was assessed by self-report questionnaire. The final outcomes were focused on the recovery of voiding, sexual, and sensory function.

Results

Eight patients met the criteria of pure conus medullaris syndrome with thoracolumbar burst fracture. The injury level were all located at L1 vertebra. There were 6 males and 2 females. Four patients had overactive neurogenic bladder, and the other 4 patients had underactive type. At final, five patients regained self-voiding function, and three required intermittent catheterization. Two male patients were sexually active, and four male patients had some sexual dysfunction. Two female patients could have normal sexual intercourse but the frequency decreased. One female patients had prolonged perineum numbness at final follow-up.

Conclusions

Although extremely rare, pure conus medullaris syndrome may occur with L1 burst fracture. Despite surgical treatment, only one half of the patients regained normal bladder and sexual function.

Factors Predicting the Surgical Risk of Osteoporotic Vertebral Compression Fractures

The aim of our study was to investigate the association between global spinal alignment, spinopelvic parameters, and outcomes of osteoporotic vertebral compression fractures (OVCF). Patients with vertebral compression fractures seen at our hospital between October 2017 and November of 2018 with a bone mineral density (BMD) T-score < -2.5 were recruited for the study. Surgical intervention was performed after eight weeks of conservative treatment depending on clinical symptoms and the willingness of patients. Spinopelvic and sagittal alignment parameters were compared between patients who had surgery and those that did not. Seventy-nine patients were included in the study. Twenty-five patients (31.6%, mean age: 73.28 ± 9.78 years) received surgery, and 54 (68.3%, mean age: 73 ± 8.58 years) conservative treatment only. Pelvic tilt, pelvic incidence, and local kyphotic angle were statistically different between the groups (all p < 0.05). A sagittal vertical axis ≥ 50 mm, distance between the C7 plumb line and the center of the fractured vertebra (DSVA) ≥ 60 mm, pelvic incidence outside of the range of 44 to 62°), and pelvic tilt ≥ 27° were associted with the need for surgical intervention. Measurement of spinopelvic parameters can predict the need for surgery in patients with OVCF.

The application of nanogenerators and piezoelectricity in osteogenesis

Bone is a complex organ possessing both physicomechanical and bioelectrochemical properties. In the view of Wolff's Law, bone can respond to mechanical loading and is subsequently reinforced in the areas of stress. Piezoelectricity is one of several mechanical responses of the bone matrix that allows osteocytes, osteoblasts, osteoclasts, and osteoprogenitors to react to changes in their environment. The present review details how osteocytes convert external mechanical stimuli into internal bioelectrical signals and the induction of intercellular cytokines from the standpoint of piezoelectricity. In addition, this review introduces piezoelectric and triboelectric materials used as self-powered electrical generators to promote osteogenic proliferation and differentiation due to their electromechanical properties, which could promote the development of promising applications in tissue engineering and bone regeneration.

Surgical outcomes after instrumented lumbar surgery in patients of eighty years of age and older

BACKGROUND

In Taiwan, the life expectancy of an 80-year-old man is 88.4 years and the life expectancy of an 80-year-old woman is 89.8 years. Some of these people will develop symptomatic degenerative lumbar diseases that interfere with an active lifestyle. These older surgical candidates usually ask the surgeon whether it would be safe to undergo surgery. However, there is no literature assessing the outcomes of laminectomy, fusion and posterior fixation for degenerative lumbar diseases in patients older than 80 years. The purpose of this study was to report the surgical outcomes of patients 80 years of age and older who underwent spinal decompression and instrumented lumbar arthrodesis for degeneration lumbar diseases.

METHODS

We retrospectively reviewed patients with degenerative lumbar diseases and spinal stenosis who underwent surgery between January 2010 and December 2012. Inclusion criteria were age greater than or equal to 80 years, decompression with instrumented lumbar arthrodesis, and at least 2 years of follow-up. Totally 89 patients were studies. Clinical outcomes were evaluated according to the Oswestry Disability Index (ODI) and visual analogue scale (VAS) of leg and back pain. Plain radiographs (lateral, anteroposterior, and flexion-extension) were used to assess the status of fusion and implant-related complications. Every complication during admission and any implant-related or failed-back syndrome requiring a second surgery was documented. T test and Fisher's exact test were used for statistical analysis.

RESULTS

Five patients were lost to follow-up, and another 12 died during the follow-up period. One patient died due to cerebral stroke just 2 days after surgery, and the other 11 patients passed away 3 months to 4 years postoperatively. In all, 72 patients had an adequate follow-up: 44 were female and 28 were male. The average age at surgery was 82.5 ± 2.6 years (80 to 93); 63 patients underwent their first lumbar surgery, and nine patients received a second surgery. Patients underwent arthrodesis surgeries were from a single-level to a 7-level. Four patients developed complications (5.6 %, 4/72). At the final follow-up, the average ODI score was lower than the preoperative score (30.0 vs. 61.8) (p < 0.001). The average VAS score also showed improvement (leg: p < 0.001; back: p < 0.001). Forty-three patients were classified as "satisfied", and 29 were "dissatisfied". Longer operation time (p = 0.014) and development of complications (p = 0.049) were related to poor clinical results. Radiographic follow-up showed that 53 patients had solid union, ten had a probable union, and nine had pseudarthrosis. More surgical segments led to a greater chance of pseudarthrosis (2.0 ± 0.9 vs 3.0 ± 1.8, p = 0.003).

CONCLUSION

Longer instrumented segments and development of complications contributed to worse clinical and radiographic outcomes. With proper patient selection, posterior decompression with instrumented fusion can be safe and effective for patients 80 years of age and older with degenerative lumbar conditions.

A 'Yang-Invigorating' Chinese herbal formula protects against gentamicin-induced nephrotoxicity in rats

The effects of VI-28 (a Yang-invigorating Chinese herbal formula) treatment on the renal mitochondrial antioxidant system and susceptibility to gentamicin-induced nephrotoxicity were investigated in rats. VI-28 treatment (80 or 240 mg/kg/day x 12) enhanced the renal mitochondrial antioxidant system, as indicated by dose-dependent increases in the level/activities of reduced glutathione, Mn-superoxide dismutase, Se-glutathione peroxidase and glutathione S-transferases. VI-28 treatment protected against nephrotoxicity induced by gentamicin administration (100 mg/kg/day x 8) and the nephroprotection was associated with an enhancement in the renal mitochondrial antioxidant system. In conclusion, VI-28 treatment enhanced the renal mitochondrial antioxidant system, thereby protecting against gentamicin nephrotoxicity.

Dang-Gui Buxue Tang produces a more potent cardioprotective effect than its component herb extracts and enhances glutathione status in rat heart mitochondria and erythrocytes

The effects of pretreatment with Dang-Gui Buxue Tang (DBT, a decoction of Astragali and Angelica roots) and its component herb extracts on myocardial ischaemia-reperfusion (IR) injury were examined in rats ex vivo. DBT and its component herb extracts could protect against myocardial IR injury in a dose-dependent manner. The more potent cardioprotection afforded by DBT pretreatment than that of a mixture of Astragali and Angelica root extracts was associated with a much higher extraction yield of active ingredients from Angelica root in the herbal decoction. The high level of active ingredients might increase their bioavailability after oral administration. DBT pretreatment could enhance myocardial mitochondrial as well as red blood cell (RBC) glutathione status, thereby increasing their resistance to oxidative stress-induced injury in rats. The measurement of RBC glutathione status may serve as a useful index for the antioxidant effect produced by DBT treatment in human subjects.

Expression of divalent metal transporter 1 (DMT1) isoforms in first trimester human placenta and embryonic tissues

BACKGROUND

Divalent metal transporter 1 (DMT1) is a transmembrane glycoprotein which mediates the proton-coupled transport of a variety of divalent metal ions. Two isoforms, which differ by the presence (DMT1-IRE) or absence (DMT1-nonIRE) of an iron-responsive element (IRE) in their 3' untranslated region, are implicated in apical iron transport and endosomal iron transport respectively. Although the expression pattern of DMT1 isoforms is tissue specific in adult, data regarding its expression in embryonic tissues are lacking.

METHODS

Semiquantitative RT-PCR and immunohistochemistry were used to study the mRNA and protein expression of both DMT1 isoforms in embryonic tissues between 8 and 14 weeks gestational age.

RESULTS

DMT1-IRE and DMT1-nonIRE expressions were ubiquitous in embryonic tissues examined. In the lung, statistically significant correlations were found between the levels of DMT1 isoform expression and gestational age. In the placenta, DMT1-IRE was the predominantly expressed isoform. Both isoform proteins were localized in embryonic epithelial cellular membrane.

CONCLUSION

Both DMT1 isoforms are ubiquitously expressed in embryonic tissues in the first trimester. Predominant DMT1-IRE isoform expression in placenta suggests an iron-regulatory mechanism reminiscent of that in the adult duodenum. Epithelial distributions of both DMT1 isoforms are associated with the absorptive or excretory functions of the expressed tissues.

Pharmacological basis of 'Yin-nourishing' and 'Yang-invigorating' actions of Cordyceps, a Chinese tonifying herb

Cordyceps sinensis (Berk.) Sacc. (Cordyceps), a popular Chinese tonifying herb, was revered for being both 'Yin-nourishing' and 'Yang-invigorating' in Chinese medicine. In order to establish the pharmacological basis for the 'Yin-nourishing' and 'Yang-invigorating' action of Cordyceps, the effects of wild and cultured Cordyceps on concanavalin A (Con A)-stimulated splenocytes, an in vitro bioassay for 'Yin-nourishment', and myocardial ATP generation capacity, an ex vivo bioassay for 'Yang-invigoration', were investigated in mice. The results indicated that methanolic extracts of wild and cultured Cordyceps enhanced both the Con A-stimulated splenocyte proliferation in vitro and myocardial mitochondrial ATP generation ex vivo in mice, with no significant difference in potency of action between the two types of Cordyceps. While the immuno-potentiating effect was associated with the increase in interleukin II production, the stimulation of myocardial ATP generation was paralleled by an enhancement in mitochondrial electron transport. When compared with typical 'Yin' and 'Yang' tonifying Chinese herbs, Cordyceps was found to possess both 'Yin-nourishing' and 'Yang-invigorating' activities, with a lower potency in both modes of action. The pharmacological characterization of Cordyceps by means of contemporary bioassays is consistent with the time-honored clinical observation from Chinese herbalists.

A yang-promoting Chinese herbal suppository preparation enhances the antioxidant status of red cells in male human subjects

In the 16-week pilot study, the effect of a Yang-promoting Chinese herbal suppository preparation (VI-28) on the red cell antioxidant status was examined in 31 healthy male subjects aged 41-66 years old. VI-28 treatment for 12 weeks (one suppository (0.3 g) daily for week 1-4; one every 2 days for week 5-8; one every 3 days for week 9-12) produced a time/dose-dependent alteration in red cell antioxidant status. The VI-28-induced change is characterized by a slight depletion in cellular reduced glutathione (GSH) level and a decrease in susceptibility to peroxide-induced lipid peroxidation as well as increases in catalase (CAT) and Cu-Zn-superoxide dismutase (SOD) activities. While a reversal trend of change was observed in cellular GSH level, the susceptibility to lipid peroxidation as well as the CAT activity after the cessation of treatment for 4 weeks, the SOD activity exhibited a protracted increase. The results indicate that VI-28 treatment enhances red cell antioxidant status in male subjects. The beneficial effect of VI-28 treatment on red cells may re fl ect a corresponding change in antioxidant status of peripheral tissues.

An in-vitro study of ginsenoside Rb1-induced teratogenicity using a whole rat embryo culture model

BACKGROUND

Ginseng is a commonly used herbal medicine worldwide. However, there is limited information regarding its effects on the developing embryo.

METHODS

The effect of ginsenoside on the developing embryo during the critical period of organogenesis was investigated using a whole rat embryo culture model. Embryos were exposed to various concentrations of ginsenoside Rb(1) and scored for growth and differentiation at the end of the culture period.

RESULTS

Median total morphological scores in embryos exposed to 30 micro g/ml of ginsenoside Rb(1) was significantly lower (P < 0.05) than that in control embryos (35 versus 45). Morphological scores for flexion, forelimb and hindlimb were also significantly reduced. The median total morphological scores further decreased to 28 when the concentration of ginsenoside Rb(1) was increased to 50 micro g/ml. At this concentration, the embryonic crown-rump length and somite number were also significantly reduced compared with control embryos (2.8 versus 3.0 mm and 16.0 versus 21.0, respectively).

CONCLUSIONS

Our study has demonstrated that ginsenoside exerts direct teratogenic effects on rat embryos. Until more is known about the effects of ginsenoside in women of reproductive age, we suggest its use should be treated with caution.

Detecting abnormal regional cerebral blood flow in patients with primary Sjögren's syndrome by technetium-99m ethyl cysteinate dimer single photon emission computed tomography of the brain--a preliminary report

Technetium-99m ethyl cysteinate dimer (Tc-99m ECD) brain single photon emission computed tomography (SPECT) was used to detect abnormal regional cerebral blood flow (rCBF) in 32 female patients with primary Sjögren's syndrome (PSS) showing definite neuropsychiatric symptoms/signs and normal brain magnetic resonance imaging (MRI) findings. It demonstrated hypoperfusion brain lesions in 18 (56.3%) of the patients, most frequently in the parietal lobes, and appears to be a sensitive tool for this clinical application.

A study of teratogenicity of hydrosalpinx fluid using a whole rat embryo culture model

BACKGROUND

Hydrosalpinx fluid may be toxic to sperm and early embryo growth. Information concerning the effect of hydrosalpinx fluid on embryo development during organogenesis is lacking.

METHODS

Rat embryos at gestational day 9.5 were cultured for 48 h with 80% rat serum and 20% of either hydrosalpinx fluid (study group) or lactated Ringer's solution (control group). Embryos were scored for growth and development at the end of the culture period.

RESULTS

Hydrosalpinx fluid, collected from 10 patients, was tested for embryotoxicity individually. Median total morphological scores were significantly lower in embryos exposed to hydrosalpinx fluid from three of the 10 patients (43.0 versus 47.0, P = 0.01; 36.0 versus 45.0, P < 0.001; 36.0 versus 46.5, P = 0.003). This was accompanied by a significant reduction in median yolk sac diameter (4.0 versus 5.2 mm, P < 0.001 and 4.0 versus 5.0 mm, P < 0.001) and somite number (17.5 versus 22.5, P < 0.001 and 17.0 versus 21.5, P = 0.008) in the latter two patients.

CONCLUSIONS

Hydrosalpinx fluid in some patients may contain toxin(s) that is potentially teratogenic.

Synergistic effects of corticosterone and kainic acid on neurite outgrowth in axotomized dorsal root ganglion

Corticosterone is the main adrenal glucocorticoids induced by stress in rats. Therapeutic use of high concentration of synthetic glucocorticoids in clinical treatment of spinal cord injury suggests that pharmacological action of glucocorticoids might be beneficial for nerve repair. In this article we cultured axotomized rat dorsal root ganglion neurons to investigate the effects of corticosterone and a glutamate receptor agonist kainic acid on neurite outgrowth. Our results revealed a synergistic effect of corticosterone and kainic acid in promoting neurite outgrowth when applied as early as one and two days in vitro, but not effective at three and four days in vitro. In addition, applied corticosterone and kainic acid were neurotoxic at three and four days in vitro but not at one and two days in vitro. The minimal concentrations of corticosterone and kainic acid to be effective were 10 microM and 1 mM, respectively. The neurotrophic effect of corticosterone and kainic acid was attenuated by the receptor tyrosine kinase A (TrkA) inhibitor AG-879. Western blot analysis and immunocytochemical studies revealed an increase of expressions of both TrkA and growth-associated protein GAP-43 in dorsal root ganglion neurons with combined treatment of corticosterone and kainic acid. Immunocytochemistry showed that corticosterone+kainic acid increase nerve growth factor immunoreactivity in dorsal root ganglion neurites and enhance GAP-43 immunointensity in dorsal root ganglion neurons. These results suggest that the neurotrophic effect of glucocorticoids on axonal regeneration might require facilitation of excitatory stimulation at an early stage of nerve injury, and nerve growth factor may mediate a growth signaling to accomplish the effect.

In vivo antioxidant action of a lignan-enriched extract of Schisandra fruit and an anthraquinone-containing extract of Polygonum root in comparison with schisandrin B and emodin

The in vivo antioxidant action of a lignan-enriched extract of the fruit of Schisandra chinensis (FS) and an anthraquinone-containing extract of the root of Polygonum multiflorum (PME) was compared with their respective active constituents schisandrin B (Sch B) and emodin by examining their effect on hepatic mitochondrial glutathione antioxidant status in control and carbon tetrachloride (CCl 4 )-intoxicated mice. FS and PME pretreatments produced a dose-dependent protection against CCl 4 hepatotoxicity, with the effect of FS being more potent. Pretreatment with Sch B, emodin or alpha-tocopherol (alpha-Toc) also protected against CCl 4 hepatotoxicity, with the effect of Sch B being more potent. The extent of hepatoprotection afforded by FS/Sch B and PME/emodin pretreatment against CCl 4 toxicity was found to correlate well with the degree of enhancement in hepatic mitochondrial glutathione antioxidant status, as evidenced by increases in reduced glutathione level and activities of glutathione reductase, glutathione peroxidase as well as glutathione S-transferases, in both control and CCl 4 -intoxicated mice. alpha-Toc, which did not enhance mitochondrial glutathione antioxidant status, seemed to be less potent in protecting against CCl 4 hepatotoxicity. The ensemble of results indicates that FS/PME produced a more potent in vivo antioxidant action than alpha-Toc by virtue of their ability to enhance hepatic mitochondrial glutathione antioxidant status and that the differential potency of FS and PME can be attributed to the difference in in vivo antioxidant potential between Sch B and emodin. Abbreviations. ALT:alanine aminotransferases CCl 4 :carbon tetrachloride FS:lignan-enriched extract of Schisandra fruit GRD:glutathione reductase GSH:reduced glutathione GSH-Px: Se-glutathione peroxidase GST:glutathione S-transferases mt:mitochondrial MDA:malondialdehyde PME:anthraquinone-containing fraction of Polygonum root Sch B:schisandrin B SDH:sorbitol dehydrogenase alpha-Toc:alpha-tocopherol

Objective evidence of abnormal regional cerebral blood flow in patients with systemic lupus erythematosus on Tc-99m ECD brain SPECT

Technetium-99m ethyl cysteinate dimer (Tc-99m ECD) brain single photon emission computed tomography (SPECT) was used to detect abnormal regional cerebral blood flow (rCBF) in 78 SLE patients with neuropsychiatric manifestations. These patients were separated into two subgroups: group 1 including 48 cases with definite neuropsychiatric symptoms/signs and group 2 with 30 cases having no neuropsychiatric symptoms/signs. Tc-99m ECD brain SPECT demonstrated hypoperfusion brain lesions in 90% and 20% of patients in groups 1 and 2, respectively. In both groups, parietal lobe and cerebellum are the most and least common areas with hypoperfusion lesions, respectively. This study suggests that Tc-99m ECD brain SPECT may provide objective information for detection of hypoperfusion brain lesions in SLE patients.

A study of diclofenac-induced teratogenicity during organogenesis using a whole rat embryo culture model

BACKGROUND

Diclofenac is a non-steroidal anti-inflammatory drug, commonly used by reproductive age women for the treatment of a variety of conditions. However, there is limited information regarding the teratogenic effects of this drug.

METHODS

The effect of diclofenac on the developing embryo during the critical period of organogenesis was investigated by using a whole rat embryo culture model. Embryos were exposed to various concentrations of diclofenac and scored for growth and differentiation at the end of the culture period.

RESULTS

Total developmental score and score for caudal neural tube, flexion and hindlimb were significantly lower in embryos exposed to high concentrations of diclofenac (7.5 and 15.0 microg/ml), but no difference in these parameters was observed when embryos were exposed to low concentration of diclofenac (1.5, 2.5 and 5.0 microg/ml). No significant differences in yolk sac diameter, crown-rump length and number of somites was found between embryos in the experimental and the control group.

CONCLUSIONS

Our study has demonstrated that diclofenac exerts direct teratogenic effects on rat embryos. Until more is known about the effects of diclofenac (especially in moderate to high doses) in women of reproductive age, we suggest its use should be treated with caution.

Levels of cord blood thyroid stimulating hormone after external cephalic version

OBJECTIVE

To investigate the relationship between breech presentation, external cephalic version and levels of cord blood thyroid stimulating hormone.

DESIGN

Case-control study.

SETTING

University teaching hospital.

POPULATION

The study group consisted of 289 consecutive singleton deliveries at term over a four-year period, all of whom had an attempt at external cephalic version performed near term for breech presentation. The control group included 23,001 singleton term deliveries during the same four-year period.

METHODS

Between group differences were compared with the Mann-Whitney U test or chi2 test when appropriate.

MAIN OUTCOME MEASURES

Levels of cord blood thyroid stimulating hormone and the incidence of false positive screening results for congenital hypothyroidism.

RESULTS

Babies who were born vaginally after prior successful external cephalic version had significantly higher median levels of cord blood thyroid stimulating hormone (6.4 vs 6.0 mlU/L, P = 0.034) and the incidence of false positive screening for thyroid stimulating hormone (12.9% vs 7.2%, P = 0.016, OR 1.9) compared with babies with spontaneous cephalic presentation. In babies with a breech presentation born by elective caesarean section, previous attempts at external cephalic version had no effect on cord blood thyroid stimulating hormone levels. There was also no difference in the levels of cord blood thyroid stimulating hormone between cephalic and breech-presenting fetuses born by elective caesarean section. However, breech-presenting babies born by emergency caesarean section after onset of labour had higher median levels of cord thyroid stimulating hormone than those with cephalic presentation (5.1 vs 4.5 mIU/L, P= 0.008).

CONCLUSION

Levels of cord blood thyroid stimulating hormone are elevated in babies born vaginally after a successful external cephalic version. This finding may represent a biological difference in fetal response to the stress of labour in breech-presenting fetuses, which is not correctable by a successful external cephalic version.

Expression of c-met and WT-1

Protooncogenes and tumor-suppressor genes are two types of genes associated with cancer development.

Porcine somatotrophin differentially down-regulates expression of the GLUT4 and fatty acid synthase genes in pig adipose tissue

The present study was conducted to determine whether porcine somatotropin (pST) differentially regulates expression of the GLUT4 and fatty acid synthase (FAS) genes in pig adipose tissue. Three different experiments were conducted in which pigs were treated daily with different doses of pST for different time periods (7 or 14 d and from 60 to 90 kg of body wt). In these experiments, pST significantly and consistently decreased FAS mRNA levels (80%, 66% and 85%, respectively); however, GLUT4 mRNA was not affected by pST in two of the three experiments, and in the one showing an effect (Experiment 2), the decrease was less than observed for FAS (44%). Because of these results, we conducted subsequent experiments to see if the effects of pST on glucose metabolism in cultured pig adipose tissue (48 h) differed when glucose concentrations were changed from 1 to 5 mmol/L. These studies revealed that the antagonistic effect of pST on insulin action was more potent when glucose transport was saturated (5 mmol/L) than when glucose concentration limited glucose entry into the cell (1 mmol/L). In summary, these results suggest that the effects of pST on glucose transport in pig adipocytes are secondary to changes elicited by the hormone on intracellular glucose use for lipogenesis. When considered in the context of the decrease previously observed in glucose transport in pig adipocytes, the findings reported herein suggest that pST acts to decrease GLUT4 protein activity and/or distribution between the plasma membrane and the intracellular pool with little alteration in GLUT4 gene expression or total cell GLUT4 protein.

Cloning of a pig glucose transporter 4 cDNA fragment: use in developing a sensitive ribonuclease protection assay for quantifying low-abundance glucose transporter 4 mRNA in porcine adipose tissue

A 246-bp fragment of porcine glucose transporter 4 (GLUT4) cDNA was cloned by polymerase chain reaction (PCR) from porcine adipose tissue RNA. Nucleotide sequences 1-138 and 139-246 of the GLUT4 cDNA share 78% sequence identity with exon 4a and 91% sequence identity with exon 4b of the human GLUT4 gene, respectively. The GLUT4 cDNA fragment was subcloned into pGEM-4Z vector to synthesize a highly specific riboprobe that hybridized only to human GLUT4 cDNA but not to human glucose transporter 1 (GLUT1) cDNA. Northern blot analysis of total RNA revealed the presence of a single transcript of 2.8 kb in porcine adipose tissue. Cloning a fragment of the GLUT4 cDNA enabled us to develop a ribonuclease protection assay for detecting porcine GLUT4 mRNA. The ribonuclease (RNase) protection assay is highly reproducible and retains a sensitivity level to as little as 2 pg of GLUT4 mRNA. The standard curve was linear between 2 and 128 pg of sense-strand GLUT4 RNA (r = .994). The ability to detect small quantities of GLUT4 mRNA is important when the abundance of GLUT4 mRNA is low and the quantity of tissue is limiting (e.g., when RNA is extracted from cultured adipose tissue). When porcine adipose tissue explants were cultured in the presence of insulin (10 ng/mL), GLUT4 mRNA abundance was increased. Development of a sensitive assay to quantify GLUT4 mRNA in porcine adipose tissue will enable us to conduct studies to increase our understanding of the molecular mechanisms by which porcine somatotropin (pST) regulates GLUT4 gene expression.