Thumb Ossification Composite Index (TOCI) for Predicting Peripubertal Skeletal Maturity and Peak Height Velocity in Idiopathic Scoliosis: A Validation Study of Premenarchal Girls with Adolescent Idiopathic Scoliosis Followed Longitudinally Until Skeletal Maturity

BACKGROUND

Accurate skeletal maturity assessment is important to guide clinical evaluation of idiopathic scoliosis, but commonly used methods are inadequate or too complex for rapid clinical use. The objective of the study was to propose a new simplified staging method, called the thumb ossification composite index (TOCI), based on the ossification pattern of the 2 thumb epiphyses and the adductor sesamoid bone; to determine its accuracy in predicting skeletal maturation when compared with the Sanders simplified skeletal maturity system (SSMS); and to validate its interrater and intrarater reliability.

METHODS

Hand radiographs of 125 girls, acquired when they were newly diagnosed with idiopathic scoliosis prior to menarche and during longitudinal follow-up until skeletal maturity (a minimum of 4 years), were scored with the TOCI and SSMS. These scores were compared with digital skeletal age (DSA) and radius, ulna, and small hand bones (RUS) scores; anthropometric data; peak height velocity; and growth-remaining profiles. Correlations were analyzed with the chi-square test, Spearman and Cramer V correlation methods, and receiver operating characteristic curve analysis. Reliability analysis using the intraclass correlation (ICC) was conducted.

RESULTS

Six hundred and forty-five hand radiographs (average, 5 of each girl) were scored. The TOCI staging system was highly correlated with the DSA and RUS scores (r = 0.93 and 0.92, p < 0.01). The mean peak height velocity (and standard deviation) was 7.43 ± 1.45 cm/yr and occurred at a mean age of 11.9 ± 0.86 years, with 70.1% and 51.4% of the subjects attaining their peak height velocity at TOCI stage 5 and SSMS stage 3, respectively. The 2 systems predicted peak height velocity with comparable accuracy, with a strong Cramer V association (0.526 and 0.466, respectively; p < 0.01) and similar sensitivity and specificity on receiver operating characteristic curve analysis. The mean age at menarche was 12.57 ± 1.12 years, with menarche occurring over several stages in both the TOCI and the SSMS. The growth remaining predicted by TOCI stage 8 matched well with that predicted by SSMS stage 7, with a mean of <2 cm/yr of growth potential over a mean of <1.7 years at these stages. The TOCI also demonstrated excellent reliability, with an overall ICC of >0.97.

CONCLUSIONS

The new proposed TOCI could provide a simplified staging system for the assessment of skeletal maturity of subjects with idiopathic scoliosis. The index needs to be subjected to further multicenter validation in different ethnic groups.

[Factors correlated with height gain after posterior spinal correction surgery in lenke 1 adolescent idiopathic scoliosis]

Objective: To investigate the correlated factors of height gain (ΔSH) after posterior spinal correction surgery in Lenke 1 adolescent idiopathic scoliosis (AIS), and to propose the predictive model of ΔSH. Methods: From 2013 to 2015, a total of 150 Lenke 1 AIS patients undergoing posterior spinal correction surgery were included in the study, with the age of (14.3±2.9) years. The Cobb angle of major curve, thoracic kyphosis (TK) and lumbar lordosis (LL) were measured on both pre-op and post-op standing whole spine x-rays. The change in Cobb angle, TK and LL were calculated. The difference between pre-operation and post-operation was compared and the linear regression analysis was used for the predictive model of ΔSH. Results: The pre-op and post-op values were (41.6±3.0)cm and (43.9±2.7)cm for spinal height (SH)[ΔSH=(2.4±0.8)cm, P=0.000]; (50.5±10.4)° and (14.6±6.4)° for Cobb angle (P=0.000). The Pearson correlation analysis showed that ΔSH was significantly correlated with pre-op SH (P=0.000), pre-op Cobb angle (P=0.000), pre-op TK (P=0.000), post-op SH (P=0.020), post-op Cobb angle (P=0.000), change in Cobb angle (P=0.000) and change in TK (P=0.000). The linear regression model 1 revealed that ΔSH was linearly correlated with change in Cobb angle (P=0.000) as well as change in TK (P=0.000); the linear regression model 2 showed that the pre-op Cobb angle (P=0.000) and pre-op TK (P=0.020) could be used for the pre-op prediction of ΔSH. Conclusions: The positively correlated factors of ΔSH include pre-op and post-op Cobb angle, TK, change in Cobb angle and change in TK. High pre-op Cobb angle and TK indicates high height gain in Lenke 1 AIS patients.

[Tea, coffee intakes and risk of oral squamous cell carcinoma: a case-control study]

Objective: To evaluate the effects of tea and coffee intakes on oral squamous cell carcinoma (OSCC) stratified by milk intake. Methods: A case-control study involving 593 OSCC patients confirmed by pathological diagnoses and 1 128 gender-age frequency matched controls was conducted in Fujian province during September 2010-March 2016. Unconditional logistic regression was used to calculate adjusted odds ratios (aORs) and corresponding 95% confidence intervals (CIs) to assess the effects of coffee, tea intakes and related variables on OSCC. Additive interaction was estimated by relative excess risk interaction (RERI), attributable proportions interaction (API) and synergy index (SI). Results: Tea intake was significantly associated with decreased risk of OSCC: the adjusted ORs were 0.54 for all subjects (95%CI: 0.41-0.71), 0.47 for milk consumers (95%CI: 0.31-0.71) and 0.57 for non-milk consumers (95%CI: 0.40-0.81). Moreover, starting tea drinking at age ≥25 years, moderate tea concentration and water temperature, drinking green tea and oolong tea showed effects to decrease the risk for OSCC in three groups. Additionally, there was a tendency of a reduced risk with increased daily tea drinking and longer tea-drinking period (all trend P<0.05). No significant association was observed between coffee intake and OSCC. A multiplicative but not additive interactions was found between tea drinking and milk intake. Additionally, we did not observe multiplicative and additive interaction between coffee drinking and milk intake. Conclusion: Tea drinking is a protective factor for OSCC, and there is a multiplicative interaction between tea drinking and milk intake. Therefore, tea drinking and increasing intake of milk can reduce the risk of OSCC at certain extent.

[Clinical application of three-dimensional O-arm navigation system in treating patients with dystrophic scoliosis secondary to neurofibromatosis type Ⅰ]

Objective: To investigate the clinical outcomes and the accuracy of O-arm-navigation system assisted pedicle screw insertion in dystrophic scoliosis secondary to neurofibromatosis type Ⅰ(NF-1). Methods: A retrospective study was conducted in 41 patients with dystrophic NF-1-associated thoracic scoliosis who were surgically treated at Department of Orthopaedics, Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School between June 2012 and October 2014 with more than 18 months follow-up. The patients were then divided into two groups: 18 patients were under the assistance of O-arm-navigation-based pedicle screw insertion (O-arm group) and the remaining 23 patients' pedicle screws insertion were conducted by free-hand (free-hand group). The X-ray and CT were analyzed to investigate the correction rate and safety of pedicle insertion. t-test was used to analyze measurement data and χ(2) test was used to analyze accuracy of screw insertion between the two groups. Results: The mean coronal Cobb angle was 63.2°±8.7° in the O-arm group and 66.9°±7.4° in the free-hand group (P>0.05), which was then corrected into 23.1°±6.8° and 30.2°±7.6°(t=2.231, P=0.031) after surgery respectively.Operation time was (265.0±70.3)minutes and estimated blood loss was (1 024±465)ml in the O-arm group. Operation time and estimated blood loss was (243.0±49.6)minutes and (1 228±521)ml respectively in the free-hand group, which had no significant difference between the two groups. However, the implant density was higher in the O-arm group than that in the free-hand group ((64.1±10.8)% vs.(44.3±15.3)%)(t=4.652, P=0.000). The O-arm group comprised 122 screws, of which 72.9% were excellent, 22.1% were good and 4.9% were bad. The free-hand group comprised 136 screws and 48.5% of them were excellent, 33.8% were good and 17.6% were bad.Accuracy of pedicle screw insertion was higher in the O-arm group than that in the free-hand group(χ(2)=10.140, P<0.05). By June 2016, the average follow-up period was (20.9±3.4)months(ranging from18 to 26 months), including (20.3±3.1)months in the O-arm group and (21.4±5.5)months in the free-hand group. At last follow-up point, coronal correction loss was significantly higher in the free-hand group than that in the O-arm group (6.3°±2.6° vs. 4.4°±1.6°)(t=2.719, P=0.009). Conclusions: Compared with free-hand technique, O-arm-navigation technique could enhance accuracy of pedicle insertion and implant density of dystrophic region in dystrophic NF-1-associated scoliosis patients, which result in a better correction rate and less correction loss. Besides, the advantage of O-arm-navigation do not increase operative time and estimate blood loss.

[Pickled food, fish, seafood intakes and oral squamous cell carcinoma: a case-control study]

Objective: To investigate the effects between fish, seafood and pickled food intakes on oral squamous cell carcinoma (OSCC). Methods: A case-control study was carried out in Fujian area during September 2010 to December 2016, in which 604 newly diagnosed primary OSCC cases confirmed by pathological diagnosis were collected from hospital and 1 343 control subjects were enrolled from community and healthy hospital population. Demographic data, history of smoking drinking and tea drinking, oral hygiene status and dietary behaviors (fish, seafood and pickled food intakes) were collected by in-person interviews using a standard questionnaire.Using unconditional logistic regression to estimate adjusted odds ratios (ORs) and corresponding 95% confidence intervals (CIs) to assess the effects of fish, seafood and pickled food intakes on OSCC. Analysis stratified by smoking, alcohol drinking and bad prosthesis to explore the possible difference in association between subgroups. Multiplicative interactions and additive interactions between fish and bad prosthesis, seafood and alcohol drinking, pickled food and bad prosthesis were assessed by unconditional logistic regression, relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP) and synergy index (S). Results: The average age of case group and control group were separately (58.69±13.92) years old and (59.27±11.37) years old (χ(2)=4.75, P=0.191). The people whose fish and seafood intakes ≥3 times/week had the lower risk of OSCC, the adjusted OR (95%CI) values were 0.63 (0.52-0.77) and 0.51 (0.41-0.64); The stratified analysis indicated that the people having bad prosthesis had the lower risk of OSCC if they eating fish ≥3 times/week, and the adjusted OR (95%CI) values was 0.53 (0.39-0.71); the people having bad prosthesis had the higher risk of OSCC if they eating pickled food ≥3 times/week, the adjusted OR (95%CI) values was 1.37 (1.02-1.88). Regularly eating seafood can decrease the risk of OSCC for non-smokers, smokers, non-drinkers, drinkers, people without bad prosthesis and had bad prosthesis, the adjusted OR (95%CI) values were 0.49 (0.36-0.68), 0.52 (0.37-0.73), 0.41 (0.31-0.55), 0.77 (0.51-0.96), 0.49 (0.36-0.67), 0.59 (0.42-0.83). Crossover analysis showed fish and bad prosthesis exist multiplication interaction relationship (adjusted OR=0.66, 95%CI: 0.44-0.97) and additional interaction relationship (RERI=-0.81, 95%CI:-1.43--0.19; AP=-0.76, 95%CI:-1.35--0.17; S=0.08, 95%CI: 0.01-0.98); pickled food and bad prosthesis exist multiplication interaction relationship (adjusted OR=1.63, 95%CI: 1.06-2.51) and addition interaction relationship (RERI=0.65, 95%CI:0.08-1.22; AP=0.36, 95%CI:0.10-0.62; S=5.19, 95%CI:1.32-54.49). Conclusion: Reducing the consumption of pickled food, quitting smoking and limiting alcohol consumption, and regularly eating fish and seafood can prevent the occurrence of OSCC.

Nonreciprocal Magnons and Symmetry-Breaking in the Noncentrosymmetric Antiferromagnet

Inelastic neutron scattering measurements were performed to study spin dynamics in the noncentrosymmetric antiferromagnet α-Cu_{2}V_{2}O_{7}. For the first time, nonreciprocal magnons were experimentally measured in an antiferromagnet. These nonreciprocal magnons are caused by the incompatibility between anisotropic exchange and antisymmetric Dzyaloshinskii-Moriya interactions, which arise from broken symmetry, resulting in a collinear ordered state but helical spin dynamics. The nonreciprocity introduces the difference in the phase velocity of the counterrotating modes, causing the opposite spontaneous magnonic Faraday rotation of the left- and right-propagating spin waves. The breaking of spatial inversion and time reversal symmetry is revealed as a magnetic-field-induced asymmetric energy shift, which provides a test for the detailed balance relation.

Oral Vitamin D Rapidly Attenuates Inflammation from Sunburn: An Interventional Study

The diverse immunomodulatory effects of vitamin D are increasingly being recognized. However, the ability of oral vitamin D to modulate acute inflammation in vivo has not been established in humans. In a double-blinded, placebo-controlled interventional trial, 20 healthy adults were randomized to receive either placebo or a high dose of vitamin D₃ (cholecalciferol) one hour after experimental sunburn induced by an erythemogenic dose of UVR. Compared with placebo, participants receiving vitamin D₃ (200,000 international units) demonstrated reduced expression of proinflammatory mediators tumor necrosis factor-α (P = 0.04) and inducible nitric oxide synthase (P = 0.02) in skin biopsy specimens 48 hours after experimental sunburn. A blinded, unsupervised hierarchical clustering of participants based on global gene expression profiles revealed that participants with significantly higher serum vitamin D₃ levels after treatment (P = 0.007) demonstrated increased skin expression of the anti-inflammatory mediator arginase-1 (P = 0.005), and a sustained reduction in skin redness (P = 0.02), correlating with significant expression of genes related to skin barrier repair. In contrast, participants with lower serum vitamin D₃ levels had significant expression of proinflammatory genes. Together the data may have broad implications for the immunotherapeutic properties of vitamin D in skin homeostasis, and implicate arginase-1 upregulation as a previously unreported mechanism by which vitamin D exerts anti-inflammatory effects in humans.

Field induced spontaneous quasiparticle decay and renormalization of quasiparticle dispersion in a quantum antiferromagnet

The notion of a quasiparticle, such as a phonon, a roton or a magnon, is used in modern condensed matter physics to describe an elementary collective excitation. The intrinsic zero-temperature magnon damping in quantum spin systems can be driven by the interaction of the one-magnon states and multi-magnon continuum. However, detailed experimental studies on this quantum many-body effect induced by an applied magnetic field are rare. Here we present a high-resolution neutron scattering study in high fields on an S=1/2 antiferromagnet C₉H₁₈N₂CuBr₄. Compared with the non-interacting linear spin–wave theory, our results demonstrate a variety of phenomena including field-induced renormalization of one-magnon dispersion, spontaneous magnon decay observed via intrinsic linewidth broadening, unusual non-Lorentzian two-peak structure in the excitation spectra and a dramatic shift of spectral weight from one-magnon state to the two-magnon continuum.

Spontaneous magnon decay in canted antiferromagnets has been theoretically investigated extensively, but experimental evidence is limited. Here the authors study the spin ½ antiferromagnet DLCB via neutron scattering, revealing field-induced spontaneous magnon decay associated with three-magnon interactions.

TLR3 preconditioning enhances the therapeutic efficacy of umbilical cord mesenchymal stem cells in TNBS-induced colitis via the TLR3-Jagged-1-Notch-1 pathway

Toll-like receptor-3 (TLR3) priming may enhance mesenchymal stem cell (MSC) immunosuppressive activity, but this mechanism has not been investigated in the context of inflammatory bowel disease. Thus, we assessed the immunosuppressive properties of TLR3-primed MSCs using a trinitrobenzene sulfonate (TNBS)-induced mouse model of colitis. Intraperitoneally injected polyribocytidylic acid (poly (I:C)- (a ligand of TLR3) primed human umbilical cord-derived MSCs (hUC-MSCs) migrated to the inflamed colon and effectively improved clinical and pathological manifestations in colitic mice compared with mice treated with unstimulated hUC-MSCs (UCMs). Poly (I:C)-MSCs decreased a wide range of inflammatory cytokines and increased systemic interleukin-10 (IL-10) levels in colonic tissues. Poly (I:C)-MSCs also impaired T-helper type 1/17 (Th1/17) cell expansion and enhanced the suppressive effects of regulatory T cells (Treg) in vitro and in vivo. Poly (I:C)-MSCs suppressed the proliferation of activated mesenteric lymph node (MLN) cells via the overproduction of prostaglandin E₂ (PGE₂) and upregulation of Jagged-1. PGE₂ produced by hUC-MSCs in response to poly (I:C) increased the production of IL-10 and promoted the differentiation of Treg, which could be reversed by inhibition of Notch-1. Collectively, preconditioning MSCs with poly (I:C) enhanced the therapeutic effects of hUC-MSCs in TNBS-induced colitis, and TLR3-activated Notch-1 signaling regulated the immune suppression of hUC-MSCs through the production of PGE₂.

Tamsulosin for treatment of lower urinary tract symptoms in women: a systematic review and meta-analysis

Tamsulosin has been used for the off-label treatment of lower urinary tract symptoms (LUTS) in women. Over the past few years, several randomized controlled trials (RCTs) have reported the clinical effectiveness and safety of tamsulosin for LUTS in women. Therefore, the aim of the present study was to perform a meta-analysis to evaluate the safety and efficacy of tamsulosin in treating LUTS in women, which may resolve some of the current controversies over use of the drug and provide more reliable evidence for the use of tamsulosin. A literature review was performed to identify all published RCTs of tamsulosin for the treatment of LUTS in women. The search included the following databases: PUBMED, EMBASE, the Cochrane Controlled Trail Register of Controlled Trials, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, Chinese Science and Technique Journals Database (VIP) and Wanfang Database. A systematic review and meta-analysis were conducted. Six RCTs studies involving 764 female participants were included in the analysis. Four out of the six RCTs compared tamsulosin with placebo, one RCT compared tamsulosin with prazosin and the other study compared tamsulosin with tamsulosin combined with tolterodine. Two RCTs evaluated total International Prostate Symptom Score (IPSS) and improved total IPSS compared with the placebo (standardized mean difference=-4.08, 95% confidence interval=-5.93 to -2.23, P<0.00001). IPSS (storage symptom score), IPSS (voiding symptom score) and quality-of-life score also showed the similar effects. In addition, tamsulosin improved the Overactive Bladder Questionnaire score when compared with placebo in only one RCT. For urodynamic parameters, tamsulosin improved the average flow rate and the post-void residual volume when compared with prazosin and tolterodine combined with tamsulosin, respectively. Beyond that, the other parameters showed no significant difference between the treatment and control groups. On the basis of the present evidence, tamsulosin is an effective treatment for the relief of LUTS in women when compared with placebo. However, the safety of the tamsulosin remains unknown. Further, well-conducted trials that examine long-term outcomes are required.

Disordered Route to the Coulomb Quantum Spin Liquid: Random Transverse Fields on Spin Ice in Pr_{2}Zr_{2}O_{7}

Inelastic neutron scattering reveals a broad continuum of excitations in Pr_{2}Zr_{2}O_{7}, the temperature and magnetic field dependence of which indicate a continuous distribution of quenched transverse fields (Δ) acting on the non-Kramers Pr^{3+} crystal field ground state doublets. Spin-ice correlations are apparent within 0.2 meV of the Zeeman energy. A random phase approximation provides an excellent account of the data with a transverse field distribution ρ(Δ)∝(Δ^{2}+Γ^{2})^{-1}, where Γ=0.27(1)  meV. Established during high temperature synthesis due to an underlying structural instability, it appears disorder in Pr_{2}Zr_{2}O_{7} actually induces a quantum spin liquid.

Evaluation of impact of anti-idursulfase antibodies during long-term idursulfase enzyme replacement therapy in mucopolysaccharidosis II patients

OBJECTIVES

This 109-week, nonrandomized, observational study of mucopolysaccharidosis II (MPS II) patients already enrolled in the Hunter Outcome Survey (HOS) (NCT00882921), assessed the long-term immunogenicity of idursulfase, and examined the effect of idursulfase-specific antibody generation on treatment safety (via infusion-related adverse events [IRAEs]) and pharmacodynamics (via urinary glycosaminoglycans [uGAGs]).

METHODS

Male patients ≥ 5 years, enrolled in HOS regardless of idursulfase treatment status were eligible. Blood/urine samples for anti-idursulfase antibody testing and uGAG measurement were collected every 12 weeks.

RESULTS

Due to difficulties in enrolling treatment-naïve patients, data collection was limited to 26 enrolled patients of 100 planned patients (aged 5.1-35.5 years) all of whom were non-naïve to treatment. Fifteen (58%) patients completed the study. There were 11/26 (42%) seropositive patients at baseline (Ab +), and 2/26 (8%) others developed intermittent seropositivity by Week 13. A total of 9/26 patients (35%) had ≥ 1 sample positive for neutralizing antibodies. Baseline uGAG levels were low due to prior idursulfase treatment and did not change appreciably thereafter. Ab + patients had persistently higher uGAG levels at entry and throughout the study than Ab - patients. Nine of 26 (34%) patients reported IRAEs. Ab + patients appeared to have a higher risk of developing IRAEs than Ab - patients. However, the relative risk was not statistically significant and decreased after adjustment for age.

CONCLUSIONS

50% of study patients developed idursulfase antibodies. Notably Ab + patients had persistently higher average uGAG levels. A clear association between IRAEs and antibodies was not established.

Coronal imbalance in degenerative lumbar scoliosis: Prevalence and influence on surgical decision-making for spinal osteotomy

AIMS

There is a paucity of information on the pre-operative coronal imbalance in patients with degenerative lumbar scoliosis (DLS) and its influence on surgical outcomes.

PATIENTS AND METHODS

A total of 284 DLS patients were recruited into this study, among whom 69 patients were treated surgically and the remaining 215 patients conservatively Patients were classified based on the coronal balance distance (CBD): Type A, CBD < 3 cm; Type B, CBD > 3 cm and C7 Plumb Line (C7PL) shifted to the concave side of the curve; Type C, CBD > 3 cm and C7PL shifted to the convex side.

RESULTS

A total of 99 of the 284 (34.8%) patient presented with a pre-operative coronal imbalance (mean CBD: 48.5, standard deviation 18.7 mm). More patients with a Type B malalignment were observed than with a Type C malalignment (62 versus 37). A total of 21 pf the 69 (30.4%) surgically treated patients had a post-operative coronal imbalance, which was found to be more prevalent in Type C patients (p < 0.001). At follow-up, less improvement was observed in terms of Short Form-36 Physical Component Score and visual analogue score for back pain (p = 0.034 and 0.025, respectively) in Type C patients.

CONCLUSION

This study shows that patients with Type C coronal malalignment may be at greater risk of post-operative coronal imbalance following posterior osteotomy. Cite this article: Bone Joint J 2016;98-B:1227-33.

Do environmental pollutants increase obesity risk in humans?

OBJECTIVES

Obesity has become a global epidemic and threat to public health. A good understanding of the causes can help attenuate the risk and spread. Environmental pollutants may have contributed to the rising global obesity rates. Some research reported associations between chemical pollutants and obesity, but findings are mixed. This study systematically examined associations between chemical pollutants and obesity in human subjects.

METHODS

Systematic review of relevant studies published between 1 January 1995 and 1 June 2016 by searching PubMed and MEDLINE®.

RESULTS

Thirty-five cross-sectional (n = 17) and cohort studies (n = 18) were identified that reported on associations between pollutants and obesity measures. Of them, 16 studies (45.71%) reported a positive association; none reported a sole inverse association; three (8.57%) reported a null association only; six (17.14%) reported both a positive and null association; seven (20.00%) reported a positive and inverse association; and three studies (8.57%) reported all associations (positive, inverse and null). Most studies examined the association between multiple different pollutants, different levels of concentration and in subsamples, which results in mixed results. Thirty-three studies reported at least one positive association between obesity and chemicals, such as polychlorinated biphenyls, biphenyl A, dichlorodiphenyltrichloroethane, dichlorodiphenyldichloroethylene and more. Certain chemicals, such as biphenyl A, were more likely to have high ORs ranging from 1.0 to 3.0, whereas highly chlorinated polychlorinated biphenyls were more likely to have negative ORs. Effects of chemicals on the endocrine system and obesity might vary by substance, exposure level, measure of adiposity and subject characteristics (e.g. sex and age).

CONCLUSIONS

Accumulated evidences show positive associations between pollutants and obesity in humans. Future large, long-term, follow-up studies are needed to assess impact of chemical pollutants on obesity risk and related mechanisms.

Influence of oral hygiene and its interaction with standard of education on the risk of oral cancer in women who neither smoked nor drank alcohol: a hospital-based, case-control study

We know of only limited data about the role of oral hygiene and the risk of oral cancer with different standards of education. The aim of this study was to assess the association between oral hygiene and risk of oral cancer, with stratification by standard of education, in Chinese women. We organised a case-control study with 250 women with oral cancer and 996 age-matched controls in Fujian, China. Data were collected by personal interview using a structured questionnaire. We used unconditional logistic regression with stratification by educational standard to estimate the odds ratios (OR) and 95% CI. Tooth-brushing twice a day or more was inversely related to the risk of oral cancer in women with high school education or above (OR 0.50; 95% CI 0.25 to 0.98), but not in those who were illiterate or had primary-middle school education. Wearing dentures showed an increased risk only in less well-educated women: the OR were 2.23 (95% CI 1.14 to 4.34) for the illiterate and 1.68 (95% CI 1.08 to 2.62) for the primary-middle school group. The loss of more than five teeth and oral ulceration were associated with increased risks of oral cancer in all three groups. There was also a multiplicative interaction between oral hygiene and standard of education for risk of oral cancer (p=0.001). Our results suggest that oral hygiene seems to have a critical role in the risk of oral cancer in Chinese women, but this effect may be modified by their educational standard.

[Dihydrotestosterone inhibits foam cell formation via a lectin-like ox-low-density lipoprotein receptor mediated mechanism in J774.1 cell line]

Objective: To investigate the effect of dihydrotestosterone (DHT) on lectin-like ox- low-density lipoprotein (LDL) receptor(LOX-1)expression and foam cell formation in the female macrophage cell line J774.1. Methods: In cultured J774.1 cells, after pretreated with DHT at concentrations of 1×10^-9 mol/L and 1×10^-8 mol/L, ox-LDL-induced LOX-1 expression and foam cell formation were investigated by quantitative real-time PCR, Western blotting, and oil-red O staining. Results: DHT at concentrations of 1×10^-9 mol/L and 1×10^-8 mol/L inhibited ox-LDL-induced LOX-1 mRNA (2.81±0.46 and 2.29±0.21 vs 4.71±0.31, both P<0.01) and protein expression (1.35±0.06 and 1.09±0.04 vs 1.75±0.11, both P<0.05). The effect was partly reversed by the androgen receptor (AR) blocker flutamide (87.6%, P=0.004). Oil-red O staining also revealed that DHT at concentrations of 1×10^-9 mol/L and 1×10^-8 mol/L suppressed ox-LDL-induced foam cell formation as quantified by the number of foam cells per high-power field (HPF) (36.0±3.0 and 29.1±1.3 vs 45.9±3.7, both P<0.05) and by the area of oil-red O stained particles per HPF (7 983±1 035 and 4 060±390 vs 14 750±2 489, both P<0.05). Conclusion: DHT at concentrations of 1×10^-9 mol/L and 1×10^-8 mol/L decreases LOX-1 expression and foam cell formation via AR.

Production of Human ATG Proteins for Lipidation Assays

Humans express several orthologs of yeast Atg8, in the LC3 and GABARAP families, which play crucial roles in autophagy through their covalent ligation to lipids, typically phosphatidylethanolamine (PE), in a process known as lipidation. Lipidation of LC3 and GABARAP regulates numerous facets of the autophagy process, including regulating expansion of the phagophore membrane, recruiting selected cargoes for degradation, and providing an autophagosome membrane-bound platform mediating dynamic interactions with other regulatory proteins. LC3 and GABARAP are families of related ubiquitin-like proteins (UBLs) (referred to here collectively as LC3/GABARAP), and their lipidation involves a divergent UBL conjugation cascade including ATG7, ATG3, and ATG12~ATG5-ATG16L1 acting as E1, E2, and E3 enzymes, respectively. ATG7 initiates LC3/GABARAP conjugation by catalyzing their C-terminal adenylation and conjugation to the catalytic cysteine of ATG3. Ultimately, the ATG12~ATG5-ATG16L1 complex catalyzes LC3/GABARAP ligation to a primary amino group on PE or other acceptor lipids. This chapter describes methods for expressing and purifying human LC3 or GABARAP, ATG7, ATG3, and the ATG12~ATG5-ATG16L1 complex for in vitro studies of LC3/GABARAP lipidation.

Crystallographic Characterization of ATG Proteins and Their Interacting Partners

Autophagosome formation and specific substrate recruitment during autophagy require ligation of the ubiquitin-like protein (UBL) Atg8 to the head group of the lipid phosphatidylethanolamine. Atg8 lipidation is mediated by distinctive UBL cascades involving autophagy-specific E1, E2, and E3 enzymes that differ substantially in sequence from components of other UBL conjugation cascades. Structural studies are important for elucidating the roles of Atg proteins that regulate multiple steps involved in autophagy. This chapter describes methods to prepare and crystallize selected proteins and complexes involved in autophagy UBL conjugation pathways, as a guide for strategies for structural and biochemical characterization of Atg proteins.

Aerosol synthesis of phase-controlled iron-graphene nanohybrids through FeOOH nanorod intermediates

Iron-based nanoparticles form the basis for a host of sustainable alternative technologies based on this earth-abundant, low-toxicity element that can adopt a variety of oxidation states, crystal phases, and functions. Control of size, shape, and phase stability is a challenge for many nano-iron-based technologies, especially those involving Fe0 that is susceptible to oxidation under ambient conditions. This article presents a continuous method for hybridizing Fe-based nanoparticles with carbon in the form of graphene-encapsulated Fe-based particles with core-shell symmetry that allows flexible control of iron particle size, shape, and phase stability. The method uses FeOOH nanorods and graphene oxide as precursors, and subjects them to an aerosol-phase microdroplet drying and annealing process to yield a range of Fe/C nanohybrids whose structure can be controlled through adjustment of aerosol process temperature and post-synthesis thermal treatment conditions. We demonstrate that FeOOH nanorods can be successfully encapsulated in graphene, and transform during annealing into encapsulated Fe3O4 or Fe0 nanoparticles by reductive fragmentation, where the graphene nanosack acts as a carbothermic reductant. The hybrids are characterized by vibrating sample magnetometry and Cr(VI) reduction rates in aqueous media. The Fe0-graphene hybrids show high activity, good stability, and good recyclability in aqueous Cr(VI) removal due to the effect of graphene encapsulation. The present work suggests this rapid and continuous synthesis method can produce stable Fe-based materials, and can be extended to other metal systems, where graphene encapsulation can induce in situ reduction of metal oxide precursors into zero-valent metal-graphene hybrids.

microRNA-21 mediates the TGF-β1-induced migration of keratinocytes via targeting PTEN

OBJECTIVE

The aim of this study was to investigate the molecular mechanism into the keratinocyte migration, which is promoted by Transforming growth factor-β1 (TGF-β1) during wound healing.

MATERIALS AND METHODS

In the present study, we investigated the regulation by TGF-β1 on phosphatase and tensin homolog (PTEN) expression, and microRNA-21 (miR-21) level with real-time quantitative PCR or/and Western blotting, and then examined the regulatory role of miR-21 on the PTEN expression and the mesenchymal transition, with real-time quantitative PCR, western blotting and luciferase reporter assay, and the migration of keratinocytic HaCaT cells with scratch assay.

RESULTS

It was demonstrated that miR-21 was upregulated by TGF-β1 treatment in HaCaT cells; and the upregulated miR-21 targeted the 3' UTR of PTEN gene and downregulated the PTEN expression, along with the Smad3/4 upregulation. Moreover, the miR-21 manipulation with miR-21 mimics or miR-21 inhibitor not only upregulated or downregulated the miR-21 level, but also associated with the mesenchymal transition and the migration of HaCaT cells via promoting or downregulating the FSP1 and Collagen I and the E-cadherin, and via upregulating or downregulating the migration of HaCaT cells.

CONCLUSIONS

Our results demonstrate that miR-21 mediates the TGF-β1-promoted mesenchymal transition and migration of keratinocytes during skin wound healing via targeting PTEN. This study implies that miR-21 might be an important target to promote the skin wound healing.

Conversion From Calcineurin Inhibitors to Mammalian Target-of-Rapamycin Inhibitors in Heart Transplant Recipients: A Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

Conversion from calcineurin inhibitors (CNIs) to mammalian target-of-rapamycin inhibitors (mTORi) was systematically evaluated in heart transplant recipients (HTRs) for the first time.

METHODS

MEDLINE (PUBMED), EMBASE, Cochrane Library, and clinical trial registries were searched comprehensively. After screening for eligibility, the randomized controlled trials (RCTs) comparing continuation of CNI with conversion to mTORi therapy underwent review, quality assessment, and data extraction. Outcomes analyzed including creatinine clearance, serum creatinine level, rejection, adverse effects, and triglyceride levels were expressed as mean differences (MDs) or as risk ratios (RRs) with 95% confidence intervals (CIs).

RESULTS

This is the first systematic review evaluating converting from CNI to mTORi therapy in HTRs. A total of 4 RCTs (231 HTRs, 117 vs 114) were included in our analysis. Patients converted to mTORi had a higher creatinine clearance (MD, 19.31; 95% CI [11.16, 27.46]; P < .00001) and lower serum creatinine levels (MD, -0.15; 95% CI [-0.25, -0.05]; P = .002). Patients converted to mTORi had a significantly higher occurrence of adverse effects, which included skin diseases, gastrointestinal side effects, bone marrow suppression, and infections. There was no significant difference between the 2 groups regarding graft rejection and triglyceride levels (RR, 2.61; 95% CI [0.08, 81.25]; P = .58; MD, 22.89; 95% CI [-21.86, 67.63]; P = .32).

CONCLUSIONS

Conversion from CNI to mTORi therapy may improve the renal function in HTRs, but the patients may suffer from a high incidence of mTORi-associated adverse events. Therefore, conversion to mTORi must be carefully assessed for the benefits and risks.

Meta-analysis of alkaline phosphatase and prognosis for osteosarcoma

Many studies have evaluated the relationships between alkaline phosphatase (ALP) levels and the prognosis for osteosarcoma. However, a consensus has yet to be reached. We completed a meta-analysis to assess the significance of ALP and prognosis for osteosarcoma. We retrieved eligible documents from the PubMed and Embase databases and extracted related data from those documents. The overall survival (OS), hazard ratio (HR) and event-free survival (EFS) HR were obtained after combination to evaluate the impacts of ALP levels on prognosis for osteosarcoma. After screening, a total of 12 documents published between 1999 and 2013 were included. The ALP levels on OS were evaluated in nine documents. The pooled HRs was 1.78 (95% CI: 1.52-2.07, p < .05). The ALP levels on EFS were determined in eight documents. The pooled HRs was 1.58 (95% CI: 1.37-1.82, p < .05). Begg's test (OS, p > .754; EFS, p > .386) and Egger's test (OS, p > .649; EFS, p > .274) showed that there was no significant publication bias during analytic process. In summary, our meta-analysis shows that a higher level of ALP can decrease the OS and EFS in patients with osteosarcoma and ALP is an important biological indicator for patients with osteosarcoma.

[A novel self-growing rod technique for early onset scoliosis: an experimental study based on a porcine scoliosis model]

OBJECTIVE

To evaluate the efficacy of a growth-guidance growing rod in an established porcine scoliosis model via the Cobb angle correction and the continued spinal growth.

METHODS

Immature pigs (age: 6 weeks old, weight: 6-8 kg) were instrumented and tethered using a three separate incisions fashion.After considerable scoliosis was induced, the pigs were randomly assigned to an experiment group (EG) and a sham group (SG). In EG, the growing rod was implanted and the pigs were euthanized 8 weeks postoperatively; while in SG, the whole instrumentations were only removed and the pigs were followed up over a 8-week period.Dorsoventral (DV) X-ray radiographs were taken prior to and immediately after the growing rod implanting surgery, and at 4-week intervals to assess the Cobb angle orrection and instrumentation positioning.The continued spinal growth and the rod sliding were also assessed from the radiographs.

RESULTS

Of the 16 pigs, one pig encountered infection during the inducement of the experimental scoliosis and thus was excluded from analysis.Of the remaining 15 pigs, all animals developed progressive, structural scoliosis.The 15 pigs were randomized into EG(n=10) and SG(n=5). Two pigs in EG encountered infection and were also excluded from analysis.Of the remaining 8 pigs in EG, no neurologic complications, implant failure or infection were observed.In EG, the Cobb angle of the scoliosis before the growing rod implanted was (52.1 ±14.1)° and it decreased to (25.4±15.2)° postoperatively.After 8 weeks, the Cobb angle was (20.2±11.4)°.In SG, the Cobb angle of the scoliosis after 8-week tethering period was (55.2±15.7)° and it decreased to (53.6±15.8)° after removal of the tethering.The curvature remained stable (51.2°) during the subsequent 8 weeks.During the 8-16th week, the spinal height increased 14.2 cm and radiographic analysis of the growing rod sliding revealed an average distraction of 39.8 mm in EG; while in SG, the increased spinal height was 14.9 cm.The difference of the increased spinal height between EG and SG was not significant (P=0.821).

CONCLUSION

The novel growing rod system can provide substantial correction of deformity, and additionally, allow for continually spinal growth without significant growing disturbance.

Ultrathin lensed fiber-optic probe for optical coherence tomography

We investigated and validated a novel method to develop ultrathin lensed fiber-optic (LFO) probes for optical coherence tomography (OCT) imaging. We made the LFO probe by attaching a segment of no core fiber (NCF) to the distal end of a single mode fiber (SMF) and generating a curved surface at the tip of the NCF using the electric arc of a fusion splicer. The novel fabrication approach enabled us to control the length of the NCF and the radius of the fiber lens independently. By strategically choosing these two parameters, the LFO probe could achieve a broad range of working distance and depth of focus for different OCT applications. A probe with 125μm diameter and lateral resolution up to 10μm was demonstrated. The low-cost, disposable and robust LFO probe is expected to have great potential for interstitial OCT imaging.

Sagittal alignment of the spine-pelvis-lower extremity axis in patients with severe knee osteoarthritis: A radiographic study

Objectives

Normal sagittal spine-pelvis-lower extremity alignment is crucial in humans for maintaining an ergonomic upright standing posture, and pathogenesis in any segment leads to poor balance. The present study aimed to investigate how this sagittal alignment can be affected by severe knee osteoarthritis (KOA), and whether associated changes corresponded with symptoms of lower back pain (LBP) in this patient population.

Methods

Lateral radiograph films in an upright standing position were obtained from 59 patients with severe KOA and 58 asymptomatic controls free from KOA. Sagittal alignment of the spine, pelvis, hip and proximal femur was quantified by measuring several radiographic parameters. Global balance was accessed according to the relative position of the C7 plumb line to the sacrum and femoral heads. The presence of chronic LBP was documented. Comparisons between the two groups were carried by independent samples t-tests or chi-squared test.

Results

Patients with severe KOA showed significant backward femoral inclination (FI), hip flexion, forward spinal inclination, and higher prevalence of global imbalance (27.1% versus 3.4%, p < 0.001) compared with controls. In addition, patients with FI of 10° (n = 23) showed reduced lumbar lordosis and significant forward spinal inclination compared with controls, whereas those with FI > 10° (n = 36) presented with significant pelvic anteversion and hip flexion. A total of 39 patients with KOA (66.1%) suffered from LBP. There was no significant difference in sagittal alignment between KOA patients with and without LBP.

Conclusions

The sagittal alignment of spine-pelvis-lower extremity axis was significantly influenced by severe KOA. The lumbar spine served as the primary source of compensation, while hip flexion and pelvic anteversion increased for further compensation. Changes in sagittal alignment may not be involved in the pathogenesis of LBP in this patient population.

Cite this article: W. J. Wang, F. Liu, Y.W. Zhu, M.H. Sun, Y. Qiu, W. J. Weng. Sagittal alignment of the spine-pelvis-lower extremity axis in patients with severe knee osteoarthritis: A radiographic study. Bone Joint Res 2016;5:198–205. DOI:10.1302/2046-3758.55.2000538.

Naringenin prevents TGF-β1 secretion from breast cancer and suppresses pulmonary metastasis by inhibiting PKC activation

BACKGROUND

Targeting the TGF-β1 pathway for breast cancer metastasis therapy has become an attractive strategy. We have previously demonstrated that naringenin significantly reduced TGF-β1 levels in bleomycin-induced lung fibrosis and effectively prevented pulmonary metastases of tumors. This raised the question of whether naringenin can block TGF-β1 secretion from breast cancer cells and inhibit their pulmonary metastasis.

METHODS

We transduced a lentiviral vector encoding the mouse Tgf-β1 gene into mouse breast carcinoma (4T1-Luc2) cells and inoculated the transformant cells (4T1/TGF-β1) into the fourth primary fat pat of Balb/c mice. Pulmonary metastases derived from the primary tumors were monitored using bioluminescent imaging. Spleens, lungs and serum (n = 18-20 per treatment group) were analyzed for immune cell activity and TGF-β1 level. The mechanism whereby naringenin decreases TGF-β1 secretion from breast cancer cells was investigated at different levels, including Tgf-β1 transcription, mRNA stability, translation, and extracellular release.

RESULTS

In contrast to the null-vector control (4T1/RFP) tumors, extensive pulmonary metastases derived from 4T1/TGF-β1 tumors were observed. Administration of the TGF-β1 blocking antibody 1D11 or naringenin showed an inhibition of pulmonary metastasis for both 4T1/TGF-β1 tumors and 4T1/RFP tumors, resulting in increased survival of the mice. Compared with 4T1/RFP bearing mice, systemic immunosuppression in 4T1/TGF-β1 bearing mice was observed, represented by a higher proportion of regulatory T cells and myeloid-derived suppressor cells and a lower proportion of activated T cells and INFγ expression in CD8(+) T cells. These metrics were improved by administration of 1D11 or naringenin. However, compared with 1D11, which neutralized secreted TGF-β1 but did not affect intracellular TGF-β1 levels, naringenin reduced the secretion of TGF-β1 from the cells, leading to an accumulation of intracellular TGF-β1. Further experiments revealed that naringenin had no effect on Tgf-β1 transcription, mRNA decay or protein translation, but prevented TGF-β1 transport from the trans-Golgi network by inhibiting PKC activity.

CONCLUSIONS

Naringenin blocks TGF-β1 trafficking from the trans-Golgi network by suppressing PKC activity, resulting in a reduction of TGF-β1 secretion from breast cancer cells. This finding suggests that naringenin may be an attractive therapeutic candidate for TGF-β1 related diseases.

New pathways for improved quantification of energy-dispersive X-ray spectra of semiconductors with multiple X-ray lines from thin foils investigated in transmission electron microscopy

Theoretical approaches to quantify the chemical composition of bulk and thin-layer specimens using energy-dispersive X-ray spectroscopy in a transmission electron microscope are compared to experiments investigating (In)GaAs and Si(Ge) semiconductors. Absorption correctors can be improved by varying the take-off angle to determine the depth of features within the foil or the samples thickness, or by definition of effective k-factors that can be obtained from plots of k-factors versus foil thickness or, preferably, versus the K/L intensity ratio for a suitable element. The latter procedure yields plots of self-consistent absorption corrections that can be used to determine the chemical composition, iteratively for SiGe using a set of calibration curves or directly from a single calibration curve for InGaAs, for single X-ray spectra without knowledge of sample thickness, density or mass absorption coefficients.

One Dimensional(1D)-to-2D Crossover of Spin Correlations in the 3D Magnet ZnMn2O4

We report on the intriguing evolution of the dynamical spin correlations of the frustrated spinel ZnMn₂O₄. Inelastic neutron scattering and magnetization studies reveal that the dynamical correlations at high temperatures are 1D. At lower temperature, these dynamical correlations become 2D. Surprisingly, the dynamical correlations condense into a quasi 2D Ising-like ordered state, making this a rare observation of two dimensional order on the spinel lattice. Remarkably, 3D ordering is not observed down to temperatures as low as 300 mK. This unprecedented dimensional crossover stems from frustrated exchange couplings due to the huge Jahn-Teller distortions around Mn³⁺ ions on the spinel lattice.

Disproportionate growth between the spine and pelvis in patients with thoracic adolescent scoliosis

A self-control ratio, the spine-pelvis index (SPI), was proposed for the assessment of patients with adolescent idiopathic scoliosis (AIS) in this study. The aim was to evaluate the disproportionate growth between the spine and pelvis in these patients using SPI. A total of 64 female patients with thoracic AIS were randomly enrolled between December 2010 and October 2012 (mean age 13 years, standard deviation (sd) 2.17; 9 to 18) and a further 73 healthy female patients with a mean age of 12.4 years (mean age 12.4 years, sd 2.24; 9 to 18), were randomly selected from a normal control database at our centre. The radiographic parameters measured included length of spine (LOS), height of spine (HOS), length of thoracic vertebrae (LOT), height of thoracic vertebrae (HOT), width of pelvis (WOP), height of pelvis (HOP) and width of thorax (WOT). SPI was defined as the ratio LOS/HOP. The SPI and LOT/HOP in patients with AIS showed a significant increase when compared with normal girls (p < 0.001 and p < 0.001 respectively), implying an abnormal pattern of growth of the spine relative to the pelvis in patients with AIS.

No significant difference in SPI was found in different age groups in the control group, making the SPI an age-independent parameter with a mean value of 2.219 (2.164 to 2.239). We also found that the SPI was not related to maturity in the control group.

This study, for the first time, used a self-control ratio to confirm the disproportionate patterns of growth of the spine and pelvis in patients with thoracic AIS, highlighting that the SPI is not affected by age or maturity.

Cite this article: Bone Joint J 2015;97-B:1668–74.

Analysis of Factors Affecting the Length of Hospital Stay for Patients with Diabetes

OBJECTIVE

The sharp rise in health expenditure of diabetes has become a huge financial and medical burden. A retrospective study was conducted to investigate the length of hospitalization for patients with diabetes and the control methods of the length of hospitalization, so as to improve the social and economic benefits of the hospital.

METHODS

Data of patients with diabetes who were admitted in the Guangdong Shantou Central Hospital from 2011 to 2013 were collected. Descriptive statistics and logistic regression analysis were used to explore the factors influencing the length of hospitalization for patients with diabetes such as sociological factors, disease factors, and clinical factors.

RESULTS

Univariate analysis results indicated that there were factors influencing the length of hospitalization for patients with diabetes, which were as follows: sociological factors including age (P<0.001), occupation (P=0.001), payment method (P<0.001), and the number of hospitalizations (P<0.001); disease factors including comorbidity (P<0.001) and initial glycated hemoglobin levels (P<0.001); and clinical factors including hospital-acquired infection (P<0.001), surgery (P<0.001), diagnoses within 3 days (P<0.001), department transfers (P=0.007), and treatment efficacy (P=0.003). In logistic regression analysis, 7 factors including surgery, hospital-acquired infections, comorbidities, age, payment methods, number of hospitalizations, and treatment efficacy had significant impacts on the length hospitalization for patients with diabetes.

CONCLUSION

The results of this study will be provided as a reference for a reasonable length of hospitalization of patients with diabetes.

Progression to insulin therapy among patients with type 2 diabetes treated with sitagliptin or sulphonylurea plus metformin dual therapy

AIM

To assess time to insulin initiation among patients with type 2 diabetes mellitus (T2DM) treated with sitagliptin versus sulphonylurea as add-on to metformin.

METHODS

This retrospective cohort study used GE Centricity electronic medical records and included patients aged ≥18 years with continuous medical records and an initial prescription of sitagliptin or sulphonylurea (index date) with metformin for ≥90 days during 2006-2013. Sitagliptin and sulphonylurea users were matched 1 : 1 using propensity score matching, and differences in insulin initiation were assessed using Kaplan-Meier curves and Cox regression. We used conditional logistic regression to examine the likelihood of insulin use 1-6 years after the index date for each year.

RESULTS

Propensity score matching produced 3864 matched pairs. Kaplan-Meier analysis showed that sitagliptin users had a lower risk of insulin initiation compared with sulphonylurea users (p = 0.003), with 26.6% of sitagliptin users initiating insulin versus 34.1% of sulphonylurea users over 6 years. This finding remained significant after adjusting for baseline characteristics (hazard ratio 0.76, 95% confidence interval 0.65-0.90). Conditional logistic regression analyses confirmed that sitagliptin users were less likely to initiate insulin compared with sulphonylurea users [odds ratios for years 1-6: 0.77, 0.79, 0.81, 0.57, 0.29 and 0.75, respectively (p < 0.05 for years 4 and 5)].

CONCLUSIONS

In this real-world matched cohort study, patients with T2DM treated with sitagliptin had a significantly lower risk of insulin initiation compared with patients treated with sulphonylurea, both as add-on to metformin.

Decay and Fission Hindrance of Two- and Four-Quasiparticle K Isomers in ^{254}Rf

Two isomers decaying by electromagnetic transitions with half-lives of 4.7(1.1) and 247(73) μs have been discovered in the heavy ^{254}Rf nucleus. The observation of the shorter-lived isomer was made possible by a novel application of a digital data acquisition system. The isomers were interpreted as the K^{π}=8^{-}, ν^{2}(7/2^{+}[624],9/2^{-}[734]) two-quasineutron and the K^{π}=16^{+}, 8^{-}ν^{2}(7/2^{+}[624],9/2^{-}[734])⊗8^{-}π^{2}(7/2^{-}[514],9/2^{+}[624]) four-quasiparticle configurations, respectively. Surprisingly, the lifetime of the two-quasiparticle isomer is more than 4 orders of magnitude shorter than what has been observed for analogous isomers in the lighter N=150 isotones. The four-quasiparticle isomer is longer lived than the ^{254}Rf ground state that decays exclusively by spontaneous fission with a half-life of 23.2(1.1) μs. The absence of sizable fission branches from either of the isomers implies unprecedented fission hindrance relative to the ground state.

Epitaxial diamond-hexagonal silicon nano-ribbon growth on (001) silicon

Silicon crystallizes in the diamond-cubic phase and shows only a weak emission at 1.1 eV. Diamond-hexagonal silicon however has an indirect bandgap at 1.5 eV and has therefore potential for application in opto-electronic devices. Here we discuss a method based on advanced silicon device processing to form diamond-hexagonal silicon nano-ribbons. With an appropriate temperature anneal applied to densify the oxide fillings between silicon fins, the lateral outward stress exerted on fins sandwiched between wide and narrow oxide windows can result in a phase transition from diamond-cubic to diamond-hexagonal Si at the base of these fins. The diamond-hexagonal slabs are generally 5-8 nm thick and can extend over the full width and length of the fins, i.e. have a nano-ribbon shape along the fins. Although hexagonal silicon is a metastable phase, once formed it is found being stable during subsequent high temperature treatments even during process steps up to 1050 ºC.