Biomechanical Analysis of a Newly Developed Shape Memory Alloy Hook in a Transforaminal Lumbar Interbody Fusion (TLIF) In Vitro Model

Objective

The objective of this biomechanical study was to evaluate the stability provided by a newly developed shape memory alloy hook (SMAH) in a cadaveric transforaminal lumbar interbody fusion (TLIF) model.

Methods

Six human cadaveric spines (L1-S2) were tested in an in vitro flexibility experiment by applying pure moments of ±8 Nm in flexion/extension, left/right lateral bending, and left/right axial rotation. After intact testing, a TLIF was performed at L4-5. Each specimen was tested for the following constructs: unilateral SMAH (USMAH); bilateral SMAH (BSMAH); unilateral pedicle screws and rods (UPS); and bilateral pedicle screws and rods (BPS). The L3–L4, L4–L5, and L5-S1 range of motion (ROM) were recorded by a Motion Analysis System.

Results

Compared to the other constructs, the BPS provided the most stability. The UPS significantly reduced the ROM in extension/flexion and lateral bending; the BSMAH significantly reduced the ROM in extension/flexion, lateral bending, and axial rotation; and the USMAH significantly reduced the ROM in flexion and left lateral bending compared with the intact spine (p<0.05). The USMAH slightly reduced the ROM in extension, right lateral bending and axial rotation (p>0.05). Stability provided by the USMAH compared with the UPS was not significantly different. ROMs of adjacent segments increased in all fixed constructs (p>0.05).

Conclusions

Bilateral SMAH fixation can achieve immediate stability after L4–5 TLIF in vitro. Further studies are required to determine whether the SMAH can achieve fusion in vivo and alleviate adjacent segment degeneration.     

Treatment Results in the Different Surgery of Intradural Extramedullary Tumor of 122 Cases

Study Design

A retrospective study of intradural extramedullary tumor.

Objective

To compare the treatment results in the different surgeries of spinal intradural extramedullary tumor.

Methods

The study retrospectively reviewed 122 patients. The minimally invasive surgery (MIS) group was divided into Group A (hemilaminectomy + tumor microscopic excision) and Group B (laminectomy + tumor microscopic excision + pedicle screw fixation). Meanwhile, the non-MIS group was divided into Group C (hemilaminectomy + tumor excision), Group D (laminectomy + tumor excision), and Group E (laminectomy + tumor excision + pedicle screw fixation). In order to study postoperative spinal stability, we simultaneously divided all of the subjects into three categories, namely Group HE: hemilaminectomy + tumor excision; Group LE: laminectomy + tumor excision; and Group LEPSF: laminectomy + tumor excision + pedicle screw fixation.

Results

The MIS group exhibited fewer postoperative complications (p<0.05), better short-term clinical efficacy (p<0.05) and less non-surgical cost (p<0.05) than in non-MIS group. The rate of postoperative spinal instability in hemilaminectomy was lower than in laminectomy in a single spinal segment (p<0.05). The rate of postoperative spinal instability in laminectomy + pedicle screw fixation was lower than in hemilaminectomy and laminectomy in two or more spinal segments (p<0.05).

Conclusion

In the case of appropriate surgical indications, minimally invasive surgery for intradural extramedullary tumor is a useful method that can successfully produce good clinical results and reduce non-surgical cost. In addition, pedicle screw fixation helps avoid spinal postoperative instability.     

Inflammatory thresholds and the species-specific effects of colonising bacteria in stable chronic obstructive pulmonary disease

Background

There has been increasing interest in the use of newer, culture-independent techniques to study the airway microbiome of COPD patients. We investigated the relationships between the three common potentially pathogenic microorganisms (PPMs) Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis, as detected by quantitative PCR (qPCR), and inflammation and health status in stable patients in the London COPD cohort.

Methods

We prospectively collected sputum, serum and plasma samples for analysis of airway bacterial presence and load, and airway and systemic inflammation from 99 stable COPD patients between January 2011 and October 2012. Health status was measured with St George’s Respiratory Questionnaire and COPD Assessment Test.

Results

Airway inflammation and plasma fibrinogen, but not C-reactive protein, were greater in samples with PPM detection (p < 0.001, p = 0.049 and p = 0.261, respectively). Increasing total bacterial load was associated with increasing airway (p < 0.01) but not systemic inflammation (p > 0.05). Samples with high total bacterial loads had significantly higher airway inflammation than both samples without PPM detection and those with lower loads. Haemophilus influenzae presence was associated with significantly higher levels of airway but not systemic inflammation for all given pathogen loads (p < 0.05), and was significantly greater than with other PPMs. No association was observed between inflammation and health status (p > 0.05).

Conclusions

Airway and systemic inflammation, as measured by fibrinogen, is greater in stable COPD patients with PPMs detected using the culture-independent qPCR technique. The airway, but not systemic inflammatory response, appears to have a total pathogen-load threshold and appears attributable to Haemophilus influenzae. However, discordance between inflammation and health status was observed.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-014-0114-1) contains supplementary material, which is available to authorized users.     

Trans-Endplate Pedicle Pillar System in Unstable Spinal Burst Fractures: Design,Technique, and Mechanical Evaluation

Background

Short-segment pedicle screw instrumentation (SSPI) is used for unstable burst fractures to correct deformity and stabilize the spine for fusion. However, pedicle screw loosening, pullout, or breakage often occurs due to the large moment applied during spine motion, leading to poor outcomes. The purpose of this study was to test the ability of a newly designed device, the Trans-Endplate Pedicle Pillar System (TEPPS), to enhance SSPI rigidity and decrease the screw bending moment with a simple posterior approach.

Methods

Six human cadaveric spines (T11-L3) were harvested. A burst fracture was created at L1, and the SSPI (Moss Miami System) was used for SSPI fixation. Strain gauge sensors were mounted on upper pedicle screws to measure screw load bearing. Segmental motion (T12-L2) was measured under pure moment of 7.5 Nm. The spine was tested sequentially under 4 conditions: intact; first SSPI alone (SSPI-1); SSPI+TEPPS; and second SSPI alone (SSPI-2).

Results

SSPI+TEPPS increased fixation rigidity by 41% in flexion/extension, 28% in lateral bending, and 37% in axial rotation compared with SSPI-1 (P<0.001), and it performed even better compared to SSPI-2 (P<0.001 for all). Importantly, the bending moment on the pedicle screws for SSPI+TEPPS was significantly decreased 63% during spine flexion and 47% in lateral bending (p<0.001).

Conclusion

TEPPS provided strong anterior support, enhanced SSPI fixation rigidity, and dramatically decreased the load on the pedicle screws. Its biomechanical benefits could potentially improve fusion rates and decrease SSPI instrumentation failure.     

Evaluation of Anterior Segment Parameters and Possible Influencing Factors in Normal Subjects Using a Dual Scheimpflug Analyzer

Purpose

To investigate normal anterior segment parameters and analyze the possible influencing factors using a dual Scheimpflug system.

Setting

Department of Ophthalmology, Affiliated Sixth People''s Hospital Shanghai Jiao Tong University, Shanghai, China.

Design

A prospective observational case series.

Methods

A total of 153 normal subjects (153 eyes) were studied. The anterior segment parameters, including the central corneal thickness (CCT), anterior chamber depth (ACD), pupil diameter (PD), keratoconus prediction index (KPI), simulated keratometry (SimK) values, anterior instantaneous curvature (AIC), posterior axial curvature (PAC), corneal eccentricity, total corneal power (TCP), axial curvature (AC), total corneal wavefront (TCW), high order aberration (HOA), and spherical aberration (SA), were determined using a dual Scheimpflug analyzer.

Results

The CCT and ACD were both negatively correlated with age (r = −0.203, p = 0.012; r = −0.589, p<0.001). There was no significant difference in the refractive indices of AIC and SimK. Compared with the negative correlation of HOA and SA (r = −0.358, p<0.001), a positive correlation was found between TCW and HOA (r = 0.561, p<0.001). Unlike the decreased tendency of AC, the TCP increased gradually from the center to the periphery in the central 8 mm diameter. TCP showed a significant correlation with AC in the analyzed area.

Conclusions

AIC and SimK provide different information in clinic, but the refractive indices of them showed no difference in this healthy study population, and age should be considered when using CCT and ACD values.     

Influence of Body Mass Index (BMI) on Functional Improvements at 3 Years Following Total Knee Replacement: A Retrospective Cohort Study

Background

The number of patients presenting for total knee replacement who are classified as obese is increasing. The functional benefits of performing TKR in these patients are unclear.

Aim

To assess the influence pre-operative body mass index has upon knee specific function, general health status and patient satisfaction at 3 years following total knee replacement.

Design

Retrospective comparative cohort study using prospectively collected data from an institutional arthroplasty register.

Methods

1367 patients were assessed using the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and Medical Outcomes Trust Short Form-36 (SF-36) scores supplemented by a validated measure of satisfaction pre-operatively and subsequently at 1,2 and 3 year post-operatively. Comparisons were made by dividing the cohort into 4 groups based on body mass index (BMI) 18.5–25.0 kg/m² (n = 253);>25.0–30.0 kg/m² (n = 559);>30.0−35.0 kg/m² (n = 373);>35.0 kg/m² (n = 182).

Results

Despite lower pre-operative, 1 and 3 year WOMAC and SF-36 scores patients with the highest BMIs >35.0 kg/m² experienced similar improvements to patients with a ‘normal‘ BMI (18.5–25.0 kg/m²) at 1 year (Difference in WOMAC improvement = 0.0 (95%CI −5.2 to 5.2), p = 1.00) and this improvement was sustained at up to 3 years (Difference in 1 year to 3 year improvement = 2.2 (95%CI: −2.1 to 6.5), p = 1.00). This effect was also observed for the SF-36 mental and physical component scores. Despite equivalent functional improvements levels of satisfaction in the >35.0 kg/m² group were lower than for any other BMI group (>35.0 kg/m² = 84.6% satisfied versus 18.5–5.0 kg/m² = 93.3% satisfied,p = 0.01) as was the proportion of patients who stated they would have the operation again (>35.0 kg/m² = 69.6% versus 18.5–25.0 kg/m² = 82.2%,p = 0.01).

Conclusion

Obese and morbidly obese patients gain as much functional benefit from total knee replacement as patients with lesser body mass indexes. This benefit is maintained for up to 3 years following surgery. However, these patients are less satisfied with their knee replacement and almost a third would not have the operation again.     

Factors Determining Patient-Prosthesis Mismatch after Aortic Valve Replacement – A Prospective Cohort Study

Objective

“Patient-prosthesis mismatch” (PPM) after aortic valve replacement (AVR) has been reported to increase morbidity and mortality. Although algorithms have been developed to avoid PPM, factors favouring its occurrence have not been well defined.

Design and Setting

This was a prospective cohort study performed at the Medical University of Vienna.

Patients

361 consecutive patients who underwent aortic valve replacement for isolated severe aortic stenosis were enrolled.

Main Outcome Measures

Patient- as well as prosthesis-related factors determining the occurrence of moderate and severe PPM (defined as effective orifice area indexed to body surface area ≤ 0.8 cm²/m²) were studied.

Results

Postoperatively, 172 patients (48%) were diagnosed with PPM. The fact that predominantly female patients were affected (58% with PPM diagnosis in women versus 36% in men, p<0.001) was explained by the finding that they had smaller aortic root diameters (30.5±4.7 mm versus 35.3±4.2 mm, p<0.0001) and a higher proportion of bioprosthetic valves (82% versus 62%, p<0.0001), both independent predictors of PPM (aortic root diameter: OR 0.009 [95% CI, 0.004;0.013]; p = 0.0003, presence of bioprosthetic valve: OR 0.126 [95% CI, 0.078;0.175]; p<0.0001).

Conclusions

The occurrence of PPM is determined by aortic root diameter and prosthesis type. Novel sutureless bioprostheses with optimized hemodynamic performance or transcatheter aortic valves may become a promising alternative to conventional bioprosthetic valves in the future.     

Influence of Cervical Muscle Fatigue on Musculo-Tendinous Stiffness of the Head-Neck Segment during Cervical Flexion

Aim

The aim of this study is to determine if the fatigue of cervical muscles has a significant influence on the head-neck segment musculo-tendinous stiffness.

Methods

Ten men (aged 21.2 ± 1.9 years) performed four quick-release trials of flexion at 30 and 50% MVC before and after the induction of muscular fatigue on cervical flexors. Electromyographic activity was recorded on the sternocleidomastoids (SCM) and spinal erectors (SE), bilaterally. Musculo-tendinous stiffness was calculated through the quick-release method adapted to the head-neck segment.

Results

We noticed a significant linear increase of the head-neck segment musculo-tendinous stiffness with the increase of exertion level both before (P < 0.0001) and after the fatigue procedure (P < 0.0001). However, this linear relationship was not different before and after the fatigue procedure. EMG analysis revealed a significant increase of the root mean square for the right SCM (P = 0.0002), the left SCM (P < 0.0001), the right SE (P < 0.0001), and the left SE (P < 0.0001) and a significant decrease of the median power frequency only for the right (P = 0.0006) and the left (P = 0.0003) SCM with muscular fatigue.

Discussion

We did not find significant changes in the head-neck segment musculo-tendinous stiffness with fatigue of cervical muscles. We found a significant increase in EMG activity in the SCM and the SE after the induction of fatigue of the SCM. Our findings suggest that with fatigue of cervical flexors, neck muscle activity is modulated in order to maintain the musculo-tendinous stiffness at a steady state.     

Use of Liver Stiffness Measurement for Liver Resection Surgery: Correlation with Indocyanine Green Clearance Testing and Post-Operative Outcome

Background

Liver stiffness measurement (LSM) using transient elastography has recently become available for the assessment of liver fibrosis. Whether LSM can predict the functional liver reserve in patients undergoing liver resection is not certain.

Aim

To correlate liver stiffness measurement (LSM) with indocyanine green (ICG) clearance test and liver biochemistry, and to determine its usefulness in predicting postoperative outcomes in patients undergoing liver resection.

Patients and Methods

Transient elastography and ICG clearance test were performed pre-operatively in 44 patients with hepatocellular carcinoma. The LSM and ICG retention rate at 15 minutes (R15) were correlated with pre-operative factors and post-operative outcomes.

Results

There was significant correlation between ICG R15 and LSM. In patients with LSM ≥11 kPa vs <11 kPa, there was significantly higher ICG R15 (17.1% vs 10.0% respectively, p = 0.025). For patients with ICG R15≥10% compared to those <10%, there was significantly higher LSM (12.0 vs 7.6 kPa respectively, p = 0.015). Twenty-eight patients proceeded to resection. There was a significant correlation between LSM and the peak INR after liver resection (r = 0.426, p = 0.024). There was a significant correlation between ICG R15 and the post-operative peak AST level (r = −0.414, p = 0.029) and peak ALT level (r = −0.568, p = 0.002). The operative time was a significant independent factor associated with post-operative complications and peak INR.

Conclusion

LSM correlated well with ICG R15 in patients undergoing liver resection, and predicted early post-operative complications. Addition of LSM to ICG R15 testing may provide better prognostic information for patients undergoing resection.     

Biomechanical Comparison of Osteoporotic Distal Radius Fractures Fixed by Distal Locking Screws with Different Length

Objectives

To evaluate the postoperative stability of osteoporotic distal radius fractures fixed with distal locking screws with different length.

Methods

A comminuted extra-articular dorsally unstable distal radius fracture, treated with volar locking plate system, was created. The 18 specimens were randomized into 3 groups based on distal locked screws with different length: Group A had unicortical screws with 50% length to the dorsal cortex. Group B had unicortical screws with 75% length to the dorsal cortex. Group C had bicortical screws. Axial compression and bending loads were imposed on the models before and after cycling testing as well as load to clinical and catastrophic failure.

Results

Minimum change in stiffness was observed before and after fatigue for all groups. The final stiffness to bending forces was statistically similar in all groups, but stiffness to axial compression was statistically significant different: Group A approached significance with respect to groups B and C (P = 0.017, 0.009), whereas stiffness in group B and C was statistically similar (P = 0.93). Load to clinical failure was significantly less for group A (456.54±78.59 N) compared with groups B (580.24±73.85 N) and C (591.07±38.40 N). Load to catastrophic failure was statistically similar between groups, but mean values for Group A were 18% less than means for Group C.

Conclusions

The volar locking plate system fixed with unicortical locking screws with at least 75% length not only produced early stability for osteoporotic distal radius fractures, but also avoided extensor tendon complications due to dorsal screw protrusion.     

Pancreatic Duct Patterns in Acute Pancreatitis: A MRI Study

Objectives

To study the MRI findings of the pancreatic duct in patients with acute pancreatitis.

Materials and Methods

A total of 239 patients with acute pancreatitis and 125 controls were analyzed in this study. The severity of acute pancreatitis was graded using the MR severity index (MRSI) and the Acute Physiology And Chronic Healthy Evaluation II(APACHE II) scoring systems. The number of main pancreatic duct (MPD) segments visualized, and both MPD diameter and pancreatic duct disruption were noted and compared with the severity of acute pancreatitis.

Results

The frequency of MPD segment visualization in the control group was higher than that in the acute pancreatitis group (p<0.05). The number of MPD segments visualized was negatively correlated with the MRSI score (p<0.05) and the APACHE II score (p<0.05). There was no difference in the MPD diameter between the acute pancreatitis and control groups or among the patients with different severities of acute pancreatitis (p>0.05). The prevalence of pancreatic duct disruption was 7.9% in the acute pancreatitis group. The prevalences of pancreatic duct disruption were 4.8% and 15.3% in the mild and severe acute pancreatitis groups based on the APACHE II score, respectively, and were 0%, 5.7% and 43.5% in the mild, moderate and severe acute pancreatitis groups according the MRSI score, respectively. The prevalence of pancreatic duct disruption was correlated with the severity of acute pancreatitis based on the APACHE II score (p<0.05) and MRSI score (p<0.05).

Conclusion

The pancreatic duct in acute pancreatitis patients was of normal diameter. The number of MPD segments visualized and visible pancreatic duct disruption on MRI may be supplementary indicators for determining the severity of acute pancreatitis.     

Complaints of Poor Sleep and Risk of Traffic Accidents: A Population-Based Case-Control Study

Introduction

This study aimed to determine the sleepiness-related factors associated with road traffic accidents.

Methods

A population based case-control study was conducted in 2 French agglomerations. 272 road accident cases hospitalized in emergency units and 272 control drivers matched by time of day and randomly stopped by police forces were included in the study. Odds ratios were calculated for the risk of road traffic accidents.

Results

As expected, the main predictive factor for road traffic accidents was having a sleep episode at the wheel just before the accident (OR 9.97, CI 95%: 1.57–63.50, p<0.05). The increased risk of traffic accidents was 3.35 times higher in subjects who reported very poor quality sleep during the last 3 months (CI 95%: 1.30–8.63, p<0.05), 1.69 times higher in subjects reporting sleeping 6 hours or fewer per night during the last 3 months (CI 95%: 1.00–2.85, p<0.05), 2.02 times higher in subjects reporting symptoms of anxiety or nervousness in the previous day (CI 95%: 1.03–3.97, p<0.05), and 3.29 times higher in subjects reporting taking more than 2 medications in the last 24 h (CI 95%: 1.14–9.44, p<0.05). Chronic daytime sleepiness measured by the Epworth Sleepiness Scale, expressed heavy snoring and nocturnal leg movements did not explain traffic accidents.

Conclusion

Physicians should be attentive to complaints of poor sleep quality and quantity, symptoms of anxiety-nervousness and/or drug consumption in regular car drivers.     

Target renal damage: the microvascular associations of increased aortic stiffness in patients with COPD

Background

Although renal impairment has been described in COPD, there is opportunity to evaluate further to determine nature and consider optimal management. Increased aortic stiffness, as seen in COPD, leads to reduced buffering of pulsatile flow. We hypothesised that urinary albumin creatinine ratio (UACR) would reflect glomerular damage related to aortic stiffness.

Methods

Patients with COPD and controls underwent spirometry, blood pressure, arterial stiffness - aortic pulse wave velocity (PWV) and provided a spot urine sample for UACR, with other renal biomarkers measured.

Results

The UACR was increased in patients (n = 52): 0.80 mg/mmol compared to controls (n = 34): 0.46 mg/mmol, p < 0.05. Aortic PWV was related to log₁₀ UACR in all subjects (r = 0.426, p < 0.001) and COPD patients alone. Aortic PWV was a significant variable for UACR with oxygen saturations, after accounting for potential confounders. Eight subjects (7 patients) reached a defined clinical microalbuminuria threshold, with aortic PWV greater in these patients compared to those patients without, although albuminuria is a continuum. Proximal tubular damage biomarkers, unlike the glomerular marker, were not different between patients and controls.

Conclusions

There is glomerular damage in patients with COPD evidenced by increased UACR, related to increased aortic stiffness. Besides the macrovascular prognostic implications of increased aortic stiffness, the microvascular state in COPD management should be considered.     

Effects of Acute Exposure to Moderate Altitude on Vascular Function,Metabolism and Systemic Inflammation

Background

Travel to mountain areas is popular. However, the effects of acute exposure to moderate altitude on the cardiovascular system and metabolism are largely unknown.

Objectives

To investigate the effects of acute exposure to moderate altitude on vascular function, metabolism and systemic inflammation.

Methods

In 51 healthy male subjects with a mean (SD) age of 26.9 (9.3) years, oxygen saturation, blood pressure, heart rate, arterial stiffness, lipid profiles, low density lipoprotein (LDL) particle size, insulin resistance (HOMA-index), highly-sensitive C-reactive protein and pro-inflammatory cytokines were measured at 490 m (Zurich) and during two days at 2590 m, (Davos Jakobshorn, Switzerland) in randomized order. The largest differences in outcomes between the two altitudes are reported.

Results

Mean (SD) oxygen saturation was significantly lower at 2590 m, 91.0 (2.0)%, compared to 490 m, 96.0 (1.0)%, p<0.001. Mean blood pressure (mean difference +4.8 mmHg, p<0.001) and heart rate (mean difference +3.3 bpm, p<0.001) were significantly higher at 2590 m, compared to 490 m, but this was not associated with increased arterial stiffness. At 2590 m, lipid profiles improved (median difference triglycerides −0.14 mmol/l, p = 0.012, HDL +0.08 mmol/l, p<0.001, total cholesterol/HDL-ratio −0.25, p = 0.001), LDL particle size increased (median difference +0.45 nm, p = 0.048) and hsCRP decreased (median difference −0.18 mg/l, p = 0.024) compared to 490 m. No significant change in pro-inflammatory cytokines or insulin resistance was observed upon ascent to 2590 m.

Conclusions

Short-term stay at moderate altitude is associated with increased blood pressure and heart rate likely due to augmented sympathetic activity. Exposure to moderate altitude improves the lipid profile and systemic inflammation, but seems to have no significant effect on glucose metabolism.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01130948","term_id":"NCT01130948"}}NCT01130948     

Sputum IgE and Cytokines in Asthma: Relationship with Sputum Cellular Profile

Background

Local IgE production may play a role in asthma pathogenesis. The aim of the study was to assess sputum total IgE and cytokines in asthmatics according to sputum cellular phenotype.

Methods

We studied 122 subjects including 22 non atopic healthy subjects, 41 eosinophilic (sputum eosinophils ≥3%), 16 neutrophilic (sputum neutrophils >76%) and 43 pauci-granulocytic asthmatics (sputum eosinophils <3% and sputum neutrophils ≤76%) recruited from the asthma clinic at CHU Liege.Sputum supernatant total IgE (tIgE) was measured by ImmunoCAP and sputum supernatant cytokines (IL-4, IL-5, IL-6, IL-10, IL-13, IL-17, IFN-γ and TNF-α) were measured with the Luminex xMAP Technology by using commercially available Fluorokine MAP kits.

Results

After concentrating sputum samples, total IgE was detectable in the majority of subjects. Sputum IgE was raised in asthmatics when compared to healthy subjects. Overall, asthmatics did not significantly differ from healthy subjects with respect to cytokine levels. The eosinophilic asthma phenotype, however, was characterised by raised sputum tIgE, IL-5 and IL-13 compared to healthy subjects (p<0.001, p<0.001 and p<0.05 respectively) and pauci-granulocytic asthma (p<0.01, p<0.001 and p<0.05 respectively) and raised IL-5 compared to neutrophilic asthma (p<0.01). When patients were classified according to sputum IgE levels, it appeared that IL-5, IL-6, IL-17 and TNF-α sputum supernatant levels were raised in the “IgE high” asthmatics (IgE ≥0.1 kU/l) when compared to “IgE low” asthmatics (IgE<0.1 kU/l).

Conclusion

The eosinophilic asthma phenotype was associated with raised sputum IgE and a Th2 cytokine profile. Raised sputum IgE was associated with a heterogeneous cytokine overproduction.     

Muscle MR Imaging in Tubular Aggregate Myopathy

Purpose

To evaluate with Magnetic Resonance (MR) the degree of fatty replacement and edematous involvement in skeletal muscles in patients with Tubular Aggregate Myopathy (TAM). To asses the inter-observer agreement in evaluating muscle involvement and the symmetry index of fatty replacement.

Materials and Methods

13 patients were evaluated by MR to ascertain the degree of fatty replacement (T1W sequences) according to Mercuri''s scale, and edema score (STIR sequences) according to extent and site.

Results

Fatty replacement mainly affects the posterior superficial compartment of the leg; the anterior compartment is generally spared. Edema was generally poor and almost only in the superficial compartment of the leg. The inter-observer agreement is very good with a Krippendorff''s coefficient >0.9. Data show a total symmetry in the muscular replacement (McNemar-Bowker test with p = 1).

Conclusions

MR reveals characteristic muscular involvement, and is a reproducible technique for evaluation of TAM. There may also be a characteristic involvement of the long and short heads of the biceps femoris. It is useful for aimed biopsies, diagnostic hypotheses and evaluation of disease progression.     

Effect of Meal Ingestion on Liver Stiffness in Patients with Cirrhosis and Portal Hypertension

Background and Aims

Liver stiffness is increasingly used in the non-invasive evaluation of chronic liver diseases. Liver stiffness correlates with hepatic venous pressure gradient (HVPG) in patients with cirrhosis and holds prognostic value in this population. Hence, accuracy in its measurement is needed. Several factors independent of fibrosis influence liver stiffness, but there is insufficient information on whether meal ingestion modifies liver stiffness in cirrhosis. We investigated the changes in liver stiffness occurring after the ingestion of a liquid standard test meal in this population.

Methods

In 19 patients with cirrhosis and esophageal varices (9 alcoholic, 9 HCV-related, 1 NASH; Child score 6.9±1.8), liver stiffness (transient elastography), portal blood flow (PBF) and hepatic artery blood flow (HABF) (Doppler-Ultrasound) were measured before and 30 minutes after receiving a standard mixed liquid meal. In 10 the HVPG changes were also measured.

Results

Post-prandial hyperemia was accompanied by a marked increase in liver stiffness (+27±33%; p<0.0001). Changes in liver stiffness did not correlate with PBF changes, but directly correlated with HABF changes (r = 0.658; p = 0.002). After the meal, those patients showing a decrease in HABF (n = 13) had a less marked increase of liver stiffness as compared to patients in whom HABF increased (n = 6; +12±21% vs. +62±29%,p<0.0001). As expected, post-prandial hyperemia was associated with an increase in HVPG (n = 10; +26±13%, p = 0.003), but changes in liver stiffness did not correlate with HVPG changes.

Conclusions

Liver stiffness increases markedly after a liquid test meal in patients with cirrhosis, suggesting that its measurement should be performed in standardized fasting conditions. The hepatic artery buffer response appears an important factor modulating postprandial changes of liver stiffness. The post-prandial increase in HVPG cannot be predicted by changes in liver stiffness.     

Lipidomic Assessment of Plasma and Placenta of Women with Early-Onset Preeclampsia

Introduction

Adipose tissue is responsible for triggering chronic systemic inflammatory response and these changes may be involved in the pathophysiology of preeclampsia.

Objective

To characterize the lipid profile in the placenta and plasma of patients with preeclampsia.

Methodology

Samples were collected from placenta and plasma of 10 pregnant women with preeclampsia and 10 controls. Lipids were extracted using the Bligh–Dyer protocol and were analysed by MALDI TOF-TOF mass spectrometry.

Results

Approximately 200 lipid signals were quantified. The most prevalent lipid present in plasma of patients with preeclampsia was the main class Glycerophosphoserines-GP03 (PS) representing 52.30% of the total lipid composition, followed by the main classes Glycerophosphoethanolamines-GP02 (PEt), Glycerophosphocholines-GP01 (PC) and Flavanoids-PK12 (FLV), with 24.03%, 9.47% and 8.39% respectively. When compared to the control group, plasma samples of patients with preeclampsia showed an increase of PS (p<0.0001), PC (p<0.0001) and FLV (p<0.0001). Placental analysis of patients with preeclampsia, revealed the PS as the most prevalent lipid representing 56.28%, followed by the main class Macrolides/polyketides-PK04 with 32.77%, both with increased levels when compared with patients control group, PS (p<0.0001) and PK04 (p<0.0001).

Conclusion

Lipids found in placenta and plasma from patients with preeclampsia differ from those of pregnant women in the control group. Further studies are needed to clarify if these changes are specific and a cause or consequence of preeclampsia.     

Efficacy of Single and Multiple Injections of Human Umbilical Tissue-Derived Cells following Experimental Stroke in Rats

Introduction

Human umbilical tissue-derived cells (hUTC) are a promising source of cells for regenerative treatment of stroke. In this study, we tested the efficacy of hUTC in experimental stroke and whether multiple injections of hUTC provide additional therapeutic benefits as compared to a single injection.

Methods

Adult male Wistar rats were subjected to 2 hours of middle cerebral artery occlusion (MCAo), and randomly selected animals were injected (i.v) with 3×10⁶ hUTC or with vehicle control (at day: 1, 1&3 or 1&7 after MCAo, n = 8–9/group). A battery of functional outcome tests was performed at days 1, 7, 14, 21, 28, 35, 42, 49, 56 and 63 after MCAo. Rats were sacrificed at 63 days after MCAo and lesion volumes were measured. To investigate the underlying mechanism of hUTC treatment of stroke, Von Willebrand Factor (vWF), and Synaptophysin immunostaining were performed.

Results

All hUTC treated groups, single or multiple injections, had better functional recovery compared to control (p<0.01). There was no statistically significant difference between a single and multiple injections of hUTC (p = 0.23) or between different multiple injections groups (p>0.07) in functional outcome. All hUTC treatment groups showed significant increases in Synaptophysin, vascular density and perimeter compared to the control group (p<0.05). There was no statistically significant difference between a single and multiple injections of hUTC or between the two groups of multiple injections in all immunohistochemical measurements (p>0.1).

Conclusion

hUTC treatment significantly improves long term functional outcome after stroke and promotes vascular density and synaptic plasticity. At the proscribed doses, multiple injections of hUTC were not superior to single injection therapy in both functional outcome and histological assessments.     

Gray Matter Abnormalities in Schizophrenia Patients with Tardive Dyskinesia: A Magnetic Resonance Imaging Voxel-Based Morphometry Study

Objective

The pathophysiological mechanism of TD remains unknown. All previous studies, using the region-of-interest method, focused on basal ganglion areas, were with inconsistent results. This whole-brain voxel-based morphometry (VBM) study investigate the grey matter abnormality of TD and its correlates with clinical ratings.

Method

High resolution T1-weighted brain volumetric MRI from 25 schizophrenia patients with TD (TD group), 25 age-, gender-, and handedness-matched schizophrenia patients without TD (non-TD group), and 25 matched healthy subjects (NC group) were analyzed using a VBM approach. Clinical ratings included the Positive and Negative Symptom Scale (PANSS), Abnormal Involuntary Movement Scale (AIMS), and the Simpson-Angus Scale (SAS).

Results

The TD group had significantly smaller total gray matter volumes than the NC group (p = 0.05). Compared to the non-TD group, the TD group had significantly higher PANSS negative (p<0.001), SAS (p<0.001), and AIMS (p<0.001) scores; and smaller bilateral inferior frontal gyrus, which correlated negatively with the PANSS negative scores (r = −0.366, p<0.05); and smaller right superior frontal gyrus, which correlated negatively with AIMS scores (r = −0.399, p<0.001), and PANSS general score (r = −0.338, p<0.05).

Limitations

The cross-section design can’t separate the gray matter change to TD from the context of the illness of schizophrenia, although TD with more severe clinical psychopathology could be a phenotype.

Conclusions

The schizophrenia patients with TD had significantly reduced gray matter, mostly at the bilateral inferior frontal gyrus and the right superior frontal gyrus, which correlated with severity of clinical symptoms and involuntary movement, respectively.