Effects of hip joint kinematics on the effective pelvis stiffness and hip impact force during simulated sideways falls.

Improved understanding is required on how hip fracture risk is influenced by landing configuration. We examined how hip impact dynamics was affected by hip joint kinematics during simulated sideways falls. Twelve young adults (7 males, 5 females) of mean age 23.5 (SD = 1.5) years, participated in pelvis release experiments. Trials were acquired with the hip flexed 15° and 30° for each of three hip rotations: +15° ("external rotation"), 0°, and -15° ("internal rotation"). During falls, force-deformation data of the pelvis were recorded. Outcome variables included the peak hip impact force (Fexperimental) and effective stiffness of the pelvis (k1st, ksecant, and kms) determined with different methods suggested in literature, and predicted hip impact force during a fall from standing height (F1st, Fsecant and Fms). The two-way repeated-measures ANOVA was used to test whether these variables were associated with hip joint angles. The Fexperimental, ksecant and Fsecant were associated with hip rotation (F = 5.587, p = 0.005; F = 9.278, p < 0.0005; F = 5.778, p = 0.004, respectively), and 15 %, 31 % and 17 % smaller in 15° external than internal rotation (848 versus 998 N; 24.6 versus 35.6 kN/m; 2,637 versus 3,170 N, respectively). However, none of the outcome variables were associated with hip flexion (p > 0.05). Furthermore, there were no interactions between the hip rotation and flexion for all outcome variables (p > 0.05). Our results provide insights on hip impact dynamics, which may help improve a hip model to assess hip fracture risk during a fall.

Association between Sarcopenia and Survival in Patients Undergoing Gamma Knife Surgery for Brain Metastasis from Breast Cancer: A Retrospective Single-centre Cohort Study.

AIMS: Many recent studies related to cancer surgery have reported that sarcopenia influences mortality in surgical patients. However, few comprehensive studies have examined the associations between sarcopenia and short- and long-term surgical outcomes of metastatic cancer, especially breast cancer with brain metastasis. In the present study, we investigated the association between sarcopenia and mortality in patients who underwent gamma knife radiosurgery (GKRS) for brain metastasis with breast cancer. MATERIALS AND METHODS: This retrospective study analysed 157 patients who underwent GKRS for brain metastasis with breast cancer between January 2014 and December 2018. A Cox regression analysis was carried out to evaluate the association between sarcopenia and mortality at 90 days, 180 days, 1 year, 3 years and the overall period. RESULTS: In the Cox regression analysis, sarcopenia was significantly associated with high 90-day mortality (adjusted hazard ratio 3.46, 95% confidence interval 1.24-9.67, P = 0.018), 180-day mortality (adjusted hazard ratio 2.67, 95% confidence interval 1.37-5.22, P = 0.004), 1-year mortality (adjusted hazard ratio 2.39, 95% confidence interval 1.42-4.02, P = 0.001), 3-year mortality (adjusted hazard ratio 2.39, 95% confidence interval 1.53-3.74, P < 0.001) and overall mortality (adjusted hazard ratio 2.11, 95% confidence interval 1.37-3.26, P < 0.001). CONCLUSION: Sarcopenia could be a risk factor for short- and long-term mortality in patients undergoing GKRS for brain metastasis from breast cancer.

Punctuated growth of InAs quantum dashes-in-a-well for enhanced 2-µm emission.

InAs quantum dashes (Qdash) engineered to emit near 2 µm are envisioned to be promising quantum emitters for next-generation technologies in sensing and communications. In this study, we explore the effect of punctuated growth (PG) on the structure and optical properties of InP-based InAs Qdashes emitting near the 2-µm wavelength. Morphological analysis revealed that PG led to an improvement in in-plane size uniformity and increases in average height and height distribution. A 2 × boost in photoluminescence intensity was observed, which we attribute to improved lateral dimensions and structural stabilization. PG encouraged formation of taller Qdashes while photoluminescence measurements revealed a blue-shift in the peak wavelength. We proposed that the blue-shift originates from the thinner quantum well cap and decreased distance between the Qdash and InAlGaAs barrier. This study on the punctuated growth of large InAs Qdashes is a step toward realizing bright, tunable, and broadband sources for 2-µm communications, spectroscopy, and sensing.

Effects of hip muscle activation on the stiffness and energy absorption of the trochanteric soft tissue during impact in sideways falls.

The trochanteric soft tissue attenuates impact force or absorbs impact energy during a fall on the hip (thereby helps to reduce a risk of hip fracture). While the benefits should be affected by contractions of muscles spanning the hip joint, no information is available to date. We examined how the stiffness (force attenuation capacity) and energy absorption of the trochanteric soft tissue were affected by hip muscle activation during a fall. Thirteen healthy young individuals (5 males, 8 females) participated in the pelvis release experiment. Falling trials were acquired with three muscle contraction conditions: 0-20% ("relaxed"), 20-50% ("moderate"), and 60-100% ("maximal") of the maximal voluntary isometric contraction of the gluteus medius muscle. During trials, we measured real-time force and deformation behaviour of the trochanteric soft tissue. Outcome variables included the stiffness and energy absorption of the soft tissue. The stiffness and energy absorption ranged from 56.1 to 446.9 kN/m, and from 0.15 to 2.26 J, respectively. The stiffness value increased with muscle contraction, and 59% greater in "maximal" than "relaxed" condition (232.2 (SD = 121.4) versus 146.1 (SD = 49.9)). However, energy absorption decreased with muscle contraction, and 58.9% greater in "relaxed" than "maximal" condition (0.89 (SD = 0.63) versus 0.56 (SD = 0.41)). Our results provide insights on biomechanics of the trochanteric soft tissue ("natural" padding device) during impact stage of a fall, suggesting that soft tissues' protective benefits are largely affected by the level of muscle contraction.

Long-term outcomes of ablation, liver resection, and liver transplant as first-line treatment for solitary HCC of 3 cm or less using an intention-to-treat analysis: A retrospective cohort study.

Background: Curative-intent therapies for hepatocellular carcinoma (HCC) include radiofrequency ablation (RFA), liver resection (LR), and liver transplantation (LT). Controversy exists in treatment selection for early-stage tumours. We sought to evaluate the oncologic outcomes of patients who received either RFA, LR, or LT as first-line treatment for solitary HCC ≤ 3 cm in an intention-to-treat analysis. Materials and methods: All patients with solitary HCC ≤ 3 cm who underwent RFA, LR, or were listed for LT between Feb-2000 and Nov-2018 were analyzed. Cox regression analysis was then performed to compare intention-to-treat (ITT) survival by initial treatment allocation and disease-free survival (DFS) by treatment received in patients eligible for all three treatments. Results: A total of 119 patients were identified (RFA n = 83; LR n = 25; LT n = 11). The overall intention-to-treat survival was similar between the three groups. The overall DFS was highest for the LT group. This was significantly higher than RFA (p = 0.02), but not statistically significantly different from LR (p = 0.14). After multivariable adjustment, ITT survival was similar in the LR and LT groups relative to RFA (LR HR:1.13, 95%CI 0.33-3.82; p = 0.80; LT HR:1.39, 95%CI 0.35-5.44; p = 0.60). On multivariable DFS analysis, only LT was better relative to RFA (LR HR:0.52, 95%CI 0.26-1.02; p = 0.06; LT HR:0.15, 95%CI 0.03-0.67; p = 0.01). Compared to LR, LT was associated with a numerically lower hazard on multivariable DFS analysis, though this did not reach statistical significance (HR 0.30, 95%CI 0.06-1.43; p = 0.13). Conclusion: For treatment-naïve patients with solitary HCC ≤ 3 cm who are eligible for RFA, LR, and LT, adjusted ITT survival is equivalent amongst the treatment modalities, however, DFS is better with LR and LT, compared with RFA. Differences in recurrence between treatment modalities and equipoise in ITT survival provides support for a future prospective trial in this setting.

Effect of fall characteristics on the severity of hip impact during a fall on the ground from standing height.

The magnitude of hip impact force during a fall on the ground (i.e., concrete surface) from standing height was determined. We found that this force decreases up to 59%, depending on how they land on the ground. INTRODUCTION: We determined the magnitude of hip impact force that humans may experience in the event of a fall from standing height on the ground, in order to examine how the hip impact force was affected by characteristics of a fall. METHODS: Twenty subjects mimicked a typical older adults' falls on a mat. Trials were acquired with three initial fall directions: forward, sideways, and backward. Trials were also acquired with three knee positions at the time of hip impact: knee together, knee on the mat, and free knee. During falls, attenuated vertical hip impact forces and corresponding depression of the mat were measured via a force plate placed under the mat and motion capture system, respectively. Using a mass-spring model, actual hip impact force and body stiffness during a fall on the ground were estimated. RESULTS: Hip impact force averaged 4.0 kN (SD = 1.7). The hip impact force was associated with knee condition (F = 25.6, p < 0.005), but not with fall direction (F = 0.4, p = 0.599). Compared with "knee on the mat," hip impact force averaged 59% and 45% greater in "free knee" and "knee together," respectively (4.6 versus 2.9 kN, p < 0.005; 4.3 versus 2.9 kN, p < 0.005). However, the hip impact force did not differ between "free knee" and "knee together (4.6 versus 4.3 kN, p = 0.554). CONCLUSION: Our results suggest that hip fracture risk during a fall decreases substantially, depending on how they land on the ground, informing the development of safe landing strategies to prevent fall-related hip fractures in older adults.

Effect of the proton irradiation on the thermally activated flux flow in superconducting SmBCO coated conductors.

We investigate changes in the vortex pinning mechanism caused by proton irradiation through the measurement of the in-plane electrical resistivity for H//c in a pristine and two proton-irradiated (total doses of 1 × 1015 and 1 × 1016 cm-2) SmBa2Cu3O7-δ (SmBCO) superconducting tapes. Even though proton irradiation has no effect on the critical temperature (Tc), the resulting artificial point defect causes an increase in normal state electrical resistivity. The electrical resistivity data around Tc shows no evidence of a phase transition to the vortex glass state but only broadens with increasing magnetic field due to the vortex depinning in the vortex liquid state. The vortex depinning is well interpreted by a thermally activated flux flow model in which the activation energy shows a nonlinear temperature change [Formula: see text] (q = 2). The field dependence of activation energy shows a [Formula: see text] with larger exponents above 4 T. This field dependence is mainly due to correlated disorders in pristine sample and artificially created point defects in irradiated samples. Compared with the vortex pinning due to correlated disorders, the vortex pinning due to the appropriate amount of point defects reduces the magnitude of Uo(H) in the low magnetic field region and slowly reduces Uo(H) in high magnetic fields.

Soft tissue stiffness over the hip increases with age and its implication in hip fracture risk in older adults.

Risk of hip fracture depends on the bone strength as well as the impact force delivered to the proximal femur during falls, and femoral soft tissue may help to reduce the hip fracture risk by attenuating the impact force. Femoral soft tissue stiffness was measured from a large sample, and compared how this was affected by age, gender and site. One hundred fifty healthy individuals (fifty-two young (aged between 19 and 29), forty-eight middle-aged (30-64), and fifty old (over 65)) participated. Each age group included an equal number of males and females. Using an automated hand-held indentation device, soft tissue stiffness was measured over twelve sites with respect to the greater trochanter (GT). For both left and right hips, the stiffness was associated with age (p < 0.0005), gender (p < 0.0005), and site (p < 0.0005). On average, the stiffness was 26% greater in older than young adults (321.5 versus 254.3 N/m). On average across twelve sites, the regression analysis indicated that the stiffness increases 1.33 N/m every year ("soft tissue stiffness over the hip = 1.33*age + 221.8"; R = 0.518, p < 0.0005). Furthermore, the stiffness was 18% greater in male than female (308.8 versus 262.6 N/m), and differed across twelve sites over the hip, being greatest (424.2 N/m) at the GT, and least (206.3 N/m) at the superior gluteal region. The results provide insights into the shock absorbing property of soft tissue over the hip, and inform the improvement of fall-related injury prevention interventions (i.e., hip protector, safe landing strategies) in older adults.

Evidence for a preformed Cooper pair model in the pseudogap spectra of a Ca10(Pt4As8)(Fe2As2)5 single crystal with a nodal superconducting gap.

For high-Tc superconductors, clarifying the role and origin of the pseudogap is essential for understanding the pairing mechanism. Among the various models describing the pseudogap, the preformed Cooper pair model is a potential candidate. Therefore, we present experimental evidence for the preformed Cooper pair model by studying the pseudogap spectrum observed in the optical conductivity of a Ca10(Pt4As8)(Fe2As2)5 (Tc = 34.6 K) single crystal. We observed a clear pseudogap structure in the optical conductivity and observed its temperature dependence. In the superconducting (SC) state, one SC gap with a gap size of Δ = 26 cm-1, a scattering rate of 1/τ = 360 cm-1 and a low-frequency extra Drude component were observed. Spectral weight analysis revealed that the SC gap and pseudogap are formed from the same Drude band. This means that the pseudogap is a gap structure observed as a result of a continuous temperature evolution of the SC gap observed below Tc. This provides clear experimental evidence for the preformed Cooper pair model.

Desflurane reduces intraoperative remifentanil requirements more than sevoflurane: comparison using surgical pleth index-guided analgesia.

BACKGROUND: Sevoflurane and desflurane are widely used in balanced anaesthesia in combination with opioid analgesics. The opioid remifentanil is frequently chosen because of its extremely rapid pharmacokinetics. However, intraoperative high-dose remifentanil is associated with increased postoperative pain and rescue analgesic use owing to acute tolerance and opioid-induced hyperalgesia. This study aimed to compare intraoperative remifentanil requirements during equi-minimum alveolar concentration (MAC) sevoflurane and desflurane anaesthesia via surgical pleth index-guided remifentanil administration. METHODS: Eighty-two subjects undergoing laparoscopic cholecystectomy were randomly allocated to two groups receiving either sevoflurane (n=40) or desflurane (n=42). Anaesthesia was maintained with the assigned inhaled anaesthetics and remifentanil. End-tidal anaesthetic concentration was maintained at age-corrected 1.0 MAC, and remifentanil infusion was continuously adjusted to achieve a surgical pleth index of 20-50. Mean remifentanil infusion rate, which was the primary outcome of the study, was calculated as the total infused remifentanil dose per kg body weight per minute of total operative time. RESULTS: Mean remifentanil infusion rate [mean (standard deviation)] was significantly higher in the sevoflurane group than in the desflurane group [0.192 (0.064) vs. 0.099 (0.033) µg kg-1 min-1; difference, 0.093 (95% confidence interval, 0.071-0.115); P<0.001]. CONCLUSIONS: During equi-MAC anaesthesia of 1.0 MAC, sevoflurane and desflurane did not show similar intraoperative remifentanil consumption under surgical pleth index-guided opioid administration. Further studies using other monitors with different measuring mechanisms are warranted to determine the cause of this difference. CLINICAL TRIAL REGISTRATION: NCT02830243 (ClinicalTrials.gov).

Anisotropy dependence of the fluctuation spectroscopy in the critical and gaussian regimes in superconducting NaFe1-xCo x As single crystals.

We investigate thermal fluctuations in terms of diamagnetism and magnetotransport in superconducting NaFe1-xCo x As single crystals with different doping levels. Results show that in the case of optimal doped and lightly overdoped (x = 0.03, 0.05) crystals the analysis in the critical as well as in the Gaussian fluctuation regions is consistent with the Ginzburg-Landau 3D fluctuation theory. However, in the case of strongly overdoped samples (x ≥ 0.07) the Ullah-Dorsey scaling of the fluctuation induced magnetoconductivity in the critical region confirms that thermal fluctuations exhibit a 3D anisotropic nature only in a narrow temperature region around T c (H). This is consistent with the fact that in these samples the fluctuation effects in the Gaussian region above Tc may be described by the Lawrence-Doniach approach. Our results indicate that the anisotropy of these materials increases significantly with the doping level.

Effect of pelvis impact angle on stresses at the femoral neck during falls.

Improved understanding is required of how the mechanics of the fall affect hip fracture risk. We used a hip impact simulator to determine how peak stresses at the femoral neck were affected by pelvis impact angle, hip abductor muscle force, and use of a wearable hip protector. We simulated falls from standing (2 m/s impact velocity) involving initial hip abductor muscle forces of 700 or 300 N. Trials were acquired for impact to the lateral aspect of the greater trochanter, and impact to the pelvis rotated 5°, 10° and 15° anteriorly (positive) or posteriorly (negative). Measures were acquired with and without a commercially available hip protector. During trials, we measured three-dimensional forces with a load cell at the femoral neck, and derived peak compressive and tensile stresses. Peak compressive stress increased 37% (5.91 versus 4.31 MPa; p < 0.0005) and peak tensile stress increased 209% (2.31 versus 0.75 MPa; p < 0.0005) when the pelvis impact angle changed from 15° anterior to -15° posterior. For lateral impacts, the peak tensile and compressive stresses averaged 73% and 8% lower, respectively, in the 700 N than 300 N muscle force condition, but the effect was reversed for anteriolateral or posteriolateral impacts. The attenuation in peak compressive stress from the hip protector was greatest for posteriolateral impacts (-15 to -5°; 36-41%), and least for anteriolateral (+15°; 10%). These results clarify the effects on hip fracture risk during a fall of pelvis impact angle and muscle forces, and should inform the design of improved hip protectors.

Preoperative Computed Tomography-Determined Sarcopenia and Postoperative Outcome After Surgery for Non-Small Cell Lung Cancer.

BACKGROUND: Sarcopenia, reduced skeletal muscle mass, is associated with frailty, injuries, and mortality. The purpose of this study was to evaluate the impact of computed tomography-determined sarcopenia on surgical complications and outcomes after resection of non-small cell lung cancer. METHODS: For a total 272 non-small cell lung cancer patients that underwent surgery between 2011 and 2016, cross-sectional area of muscle at the third lumbar vertebra (L3) was retrospectively measured using preoperative chest computed tomography images. Sarcopenia was defined as an L3 muscle index of <55 cm2/m2 for men and of <39 cm2/m2 for women. Clinical characteristics, postoperative complications, disease-free survival, and overall survival of patients with or without sarcopenia were compared. RESULTS: A total of 60.3% ( n = 164) were male, and mean patient age was 62.9 ± 9.6 years. The prevalence of sarcopenia was 22.4% for all study subjects, 32.9% for men, and 6.5% for women. No significant difference was observed between patients with or without sarcopenia in terms of intensive care unit or hospital stay ( p = 0.502 and p = 0.378, respectively), and the presence of sarcopenia was not associated with postoperative complications. Furthermore, no significant difference was observed between the 3-year disease-free survival rate (74.3% vs 66.7%, p = 0.639) or 3-year overall survival rate (83.9% vs 87.7%, p = 0.563) of patients with or without sarcopenia. CONCLUSION: Sarcopenia as determined by preoperative computed tomography does not appear to have a negative impact on surgical outcome or overall survival for resected non-small cell lung cancer patients.

Thermal activation energy of 3D vortex matter in NaFe1-x Co x As (x = 0.01, 0.03 and 0.07) single crystals.

We report on the thermally activated flux flow dependency on the doping dependent mixed state in NaFe1-x Co x As (x = 0.01, 0.03, and 0.07) crystals using the magnetoresistivity in the case of B//c-axis and B//ab-plane. It was found clearly that irrespective of the doping ratio, magnetoresistivity showed a distinct tail just above the T c,offset associated with the thermally activated flux flow (TAFF) in our crystals. Furthermore, in TAFF region the temperature dependence of the activation energy follows the relation [Formula: see text] with q = 1.5 in all studied crystals. The magnetic field dependence of the activation energy follows a power law of [Formula: see text] where the exponent α is changed from a low value to a high value at a crossover field of B = ∼2 T, indicating the transition from collective to plastic pinning in the crystals. Finally, it is suggested that the 3D vortex phase is the dominant phase in the low temperature region as compared to the TAFF region in our series samples.

Effect of neck flexor muscle activation on impact velocity of the head during backward falls in young adults.

Falls are a common cause of traumatic brain injuries (TBI) across the lifespan. A proposed but untested hypothesis is that neck muscle activation influences impact severity and risk for TBI during a fall. We conducted backward falling experiments to test whether activation of the neck flexor muscles facilitates the avoidance of head impact, and reduces impact velocity if the head contacts the ground. Young adults (n=8) fell from standing onto a 30cm thick gymnastics mat while wearing a helmet. Participants were instructed to fall backward and (a) prevent their head from impacting the mat ("no head impact" trials); (b) allow their head to impact the mat, but with minimal impact severity ("soft impact" trials); and (c) allow their head to impact the mat, while inhibiting efforts to reduce impact severity ("hard impact" trials). Trial type associated with peak magnitude of electromyographic activity of the sternocleidomastoid (SCM) muscles (p<0.017), and with the vertical and horizontal velocity of the head at impact (p<0.001). Peak SCM activations, expressed as percent maximal voluntary isometric contraction (%MVIC), averaged 75.3, 67.5, and 44.5%MVIC in "no head impact", "soft impact", and "hard impact" trials, respectively. When compared to "soft impact" trials, vertical impact velocities in "hard impact" trials averaged 87% greater (3.23 versus 1.73m/s) and horizontal velocities averaged 83% greater (2.74 versus 1.50m/s). For every 10% increase in SCM %MVIC, vertical impact velocity decreased 0.24m/s and horizontal velocity decreased 0.22m/s. We conclude that SCM activation contributes to the prevention and modulation of head impact severity during backward falls.

Long-term Survival Outcomes of Primary Breast Cancer in Women With or Without Preoperative Magnetic Resonance Imaging: A Matched Cohort Study.

AIMS: To investigate whether preoperative magnetic resonance imaging (MRI) in patients with primary breast cancer is predictive of disease-free (DFS) and overall survival and to determine the prognostic factors indicating survival. MATERIALS AND METHODS: This retrospective study was approved by the institutional review board and the requirement for informed consent was waived. From 2009 to 2010, 828 women with primary breast cancer and preoperative MRI were matched with 1613 women without such imaging. Patients were matched with regards to 25 patient and tumour-related covariates. A Cox proportional hazards model was used to investigate the time to recurrence and to estimate the hazard ratio for preoperative MRI. Log-rank tests and Cox proportional hazards survival analysis were carried out on total recurrence DFS and overall survival in the unmatched datasets. RESULTS: In total, 799 matched pairs were available for survival analysis. The MRI group showed a tendency towards better survival outcome; however, there were no significant differences in DFS and overall survival. Age at diagnosis (DFS hazard ratio = 0.98; overall survival hazard ratio = 1.04), larger tumour size (DFS hazard ratio = 1.01; overall survival hazard ratio = 1.02), triple negative breast cancer (DFS hazard ratio = 2.64; overall survival hazard ratio = 3.44) and the presence of lymphovascular invasion (DFS hazard ratio = 2.12; overall survival hazard ratio = 2.70) were independent significant variables for worse DFS and overall survival. CONCLUSION: Preoperative MRI did not result in an improvement in a patient's outcome. Age at diagnosis, tumour size, molecular subtype and lymphovascular invasion were significant independent factors affecting both DFS and overall survival.

Inhibition of microRNA-449a prevents IL-1ß-induced cartilage destruction via SIRT1.

OBJECTIVE: SIRT1 has anti-inflammatory as well as protective effects in chondrocytes. The object of this study was to investigate whether microRNA-449a regulates expression of SIRT1, which inhibits expression of catabolic genes in IL-1ß-induced cartilage destruction. MATERIALS AND METHODS: MicroRNA-449a expression was determined in OA chondrocytes and IL-1ß-induced chondrocytes by real-time PCR. MicroRNA-449a binding sites on the 3'-UTR of SIRT1 mRNA and binding site conservation were examined using microRNA target prediction tools. SIRT1-overexpressing or knockdown chondrocytes were transfected with microRNA-449a or anti-microRNA-449a mimic and stimulated by IL-1ß. Expression of catabolic and anabolic genes was examined by real-time PCR and western blotting. Finally, positive effects of anti-microRNA-449a on expression of these genes were confirmed by western analysis of OA chondrocytes. RESULTS: Expression of microRNA-449a was increased in OA chondrocytes and IL-1ß-induced chondrocytes. MMP-13 expression was enhanced, whereas type II collagen and SIRT1 expression were decreased in IL-1ß-induced chondrocytes. SIRT1 overexpression resulted in decreased expression of catabolic genes such as MMPs and ADAMTSs in response to IL-1ß, but these effects were moderated by microRNA-449a. Suppression of microRNA-449a by anti-microRNA-449a inhibited expression of catabolic genes despite IL-1ß stimulation, but these effects were abolished in SIRT1 knockdown chondrocytes. Furthermore, expression of catabolic genes was decreased and expression of type II collagen as well as SIRT1 was restored by anti-microRNA-449a in OA chondrocytes as well as in IL-1ß-induced chondrocytes. CONCLUSION: Silencing of microRNA-449a had a protective effect, inhibiting catabolic gene expression and restoring anabolic gene expression, by targeting SIRT1 in IL-1ß-induced cartilage destruction.

A randomised controlled trial comparing continuous supraclavicular and interscalene brachial plexus blockade for open rotator cuff surgery.

Continuous interscalene block is an approved modality for postoperative pain control, but it may cause hemidiaphragmatic paresis. In this study we aimed to determine whether continuous supraclavicular block would provide postoperative analgesia comparable to that of continuous interscalene block and reduce the incidence of hemidiaphragmatic paresis. Patients scheduled for open rotator cuff repair were randomly allocated to receive continuous interscalene (n = 38) or supraclavicular block (n = 37). Both participants and assessing clinicians were blinded to the group allocation. The primary endpoint was the mean pain intensity 24 h after the surgery. Postoperative mean (SD) pain scores at 24 h were similar in the supraclavicular and interscalene groups (2.57 (1.71) vs 2.84 (1.75) respectively; p = 0.478). The incidence of complete or partial hemidiaphragmatic paresis was lower in the supraclavicular group at 1 h after admission to the postanaesthetic care unit and 24 h after the surgery [25 (68%) vs 38 (100%); p = 0.001 and 14 (38%) vs 27 (71%) respectively; p = 0.008]. Continuous supraclavicular block provided comparable analgesia compared with interscalene block with a reduced incidence of complete or partial hemidiaphragmatic paresis for 24 h following surgery.

The effects of prophylactic bolus phenylephrine on hypotension during low-dose spinal anesthesia for cesarean section.

BACKGROUND: Continuously infused phenylephrine is frequently used to reduce the incidence of hypotension in women undergoing cesarean section under spinal anesthesia, but less is known about the prophylactic bolus method. We evaluated three prophylactic bolus doses of phenylephrine during low-dose spinal anesthesia for cesarean section. METHODS: One-hundred-and-eighty-four patients were randomized to receive 0.9% saline 2mL (Control Group) or phenylephrine 1.0µg/kg (PHE1 Group), 1.5µg/kg (PHE1.5 Group), or 2.0µg/kg (PHE2 Group) immediately after induction of combined spinal-epidural anesthesia. Maternal blood pressure and heart rate were recorded at 1-min intervals until delivery. Hypotension, defined as systolic blood pressure <80% of baseline, was treated with rescue doses of phenylephrine 100µg at 1-min intervals until hypotension resolved. The incidence of nausea, vomiting, bradycardia, and hypertension, as well as Apgar scores and umbilical blood gases, were recorded. RESULTS: The incidence of hypotension was 71.7% (33/46) in the Control Group, 68.9% (31/45) in the PHE1 Group, 37.0% (17/46) in the PHE1.5 Group and 45.7% (21/46) in the PHE2 Group (P=0.001). The total rescue dose of phenylephrine was greater in the Control Group than those in the PHE1.5 Group (P<0.05) and PHE2 Group (P<0.05). The incidence of hypertension increased as the dose of prophylactic phenylephrine increased (P<0.001) and was highest in the PHE2 group (37%). Other variables did not differ among the four groups. CONCLUSIONS: Under the conditions of this study, prophylactic bolus injection of phenylephrine 1.5µg/kg was a suitable alternative method for reducing the incidence of hypotension during low-dose spinal anesthesia for cesarean section.

Spinal Accessory Nerve: Ultrasound Findings and Correlations with Neck Lymph Node Levels.

Purpose: To evaluate the ultrasound characteristics of the spinal accessory nerve (SAN) and correlate nerve location with neck lymph node level. Materials and Methods: 50 participants with 100 SANs were enrolled in this study. The SAN was traced from the trapezius muscle to the upper neck and was identified by a hypoechoic linear structure without color Doppler flow. The ultrasound characteristics of the SAN, such as visibility, diameter, relationship with adjacent structures, and its correlation with lymph node levels, were evaluated. Results: The SAN was identified in 96 %-100 % of segments. The mean diameter of the SAN was 0.54 ±â€Š0.09 mm. The SANs was located between the trapezius and levator scapulae muscles and 90.8 % were traced into the trapezius muscle. In the upper neck, the SAN passed deep into the sternocleidomastoid (SCM) muscle in 38 % of cases and between the two heads of the SCM muscle in 62 % of cases. The SAN was found at neck lymph node levels II, III, IV, and V, but not I or VI. Conclusion: Continuous ultrasound monitoring of the SAN and its correlation with lymph node levels is possible in most patients. Our current findings may assist in the future prevention of SAN injury during ultrasound-guided procedures.