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Iron stable isotopes (δ56Fe) are a useful tool for studying Earth processes, many of which involve redox transformations between Fe(III) and Fe(II). Here, we present two related experimental efforts, a study of the kinetic isotope effects (KIEs) associated with the reduction of Fe(III)‐ethylenediaminetetraacetic acid (EDTA) to Fe(II), and measurements of the biological fractionation of Fe isotopes by phytoplankton in culture. Reductants tested were ascorbate, hydroxylamine, Mn(II), dithionite, and photoreduction at pH between 5 and 9 and temperatures from 0 to 100°C. Isotope fractionations were very large, and included both normal and inverse KIEs, ranging from −4‰ to +5‰. Experiments were reproducible, yielding similar results for triplicate experiments run concurrently and for experiments run weeks apart. However, fractionations were not predictable, without a clear relationship to reaction rate, temperature, pH, or the reductant used. Acquisition of Fe by eukaryotic phytoplankton also often involves the reduction of Fe(III) to Fe(II). Several species of diatoms and a coccolithophore were tested for Fe isotope fractionation in culture using EDTA, NTA, and DFB as Fe(III) chelating ligands, yielding fractionations from −1.3‰ to +0.6‰. Biological isotope effects were also unpredictable, showing no clear relationship to species, growth rate, or Fe concentration. Variability in Fe isotope fractionation observed in culture may be explained in part by the sensitivity of KIEs. This work has implications for the industrial purification of isotopes, interpretation of natural δ56Fe, and the use of Fe isotopes as a tracer Fe source and biological processes in the ocean and other natural systems. Plain Language Summary: The stable isotopes of iron react at slightly different rates during natural processes, giving rise to variations in Fe stable isotope ratios (δ56Fe) on Earth's surface. We therefore designed two kinds of experiments with the goal of better understanding variations in δ56Fe on Earth. First, Fe(III) bound to the organic molecule ethylenediaminetetraacetic acid was reduced to Fe(II). It was found that under some conditions the lighter isotopes reacted more quickly and under some conditions heavier isotopes reacted more quickly, however there were no clear patterns which allowed us to predict these isotope fractionations. Second, phytoplankton were grown in the laboratory, and their Fe isotope ratios were measured and compared to the media in which they were grown. In these experiments too, a range of fractionations was observed but there were no clear patterns in the results. Though our experiments did not lead to easily predictable results, they contribute to our understanding of how Fe isotopes behave; for example, the large isotope fractionations observed here might have industrial applications for isotope purification, and our work suggests that determining the magnitude of biological Fe isotope fractionation might be better accomplished by in situ observation rather than additional laboratory experiments. Key Points: Iron isotope fractionation was tested during chemical reduction of Fe(III)‐ethylenediaminetetraacetic acid to Fe(II)‐(ferrozine)3Biological fractionation of Fe isotopes was tested for eukaryotic phytoplankton in cultureResults are not easily interpreted but have implications for understanding redox kinetic isotope effects in the laboratory and in nature [ABSTRACT FROM AUTHOR]

We studied the role of KATP channels in the infarct-limiting effect of short-term normobaric hypoxia. Male Wistar rats were subjected to a 45-min coronary artery occlusion followed by a 120-min reperfusion. Normobaric hypoxia was simulated 30 min before coronary artery occlusion: 6 sessions of hypoxia (8% O2, 10 min) and reoxygenation (21% O2, 10 min). The following drugs were administered to rats: glibenclamide, 5-hydroxydecanoate, and HMR1098. It was found that normobaric hypoxia contributes to a decrease in myocardial infarct size by 36%. Preliminary administration of glibenclamide or 5-hydroxydecanoate eliminated the infarct-reducing effect of normobaric hypoxia. Activator of mitochondrial KATP channel diazoxide limited the infarct size. These findings suggest that mitochondrial KATP channels are involved into the cardioprotective effect of normobaric hypoxia [ABSTRACT FROM AUTHOR]

The cardioprotective effect of chronic hypoxia (CH) is associated with the activation of inducible nitric oxide synthase (iNOS). Reactive oxygen species (ROS) are involved in the development of CH-induced cardiac tolerance to ischemia/reperfusion. The infarct-limiting effect of CH depends on the opening of mitochondrial ATP-sensitive potassium (mitoKATP) channels. Protein kinase C δ and ε isoforms are involved in the cardioprotective effect of adaptation to hypoxia. CH increases the expression of phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2), Ca2+/calmodulin-dependent protein kinase II (CaMKII), phosphorylated p38 (p-p38), phosphorylated AMP-activated protein kinase (p-AMPK), as well as hexokinase-1 (HK1) and hexokinase-2 (HK2). ERK1/2 and mitogen-activated protein kinases (MEK1/2) are involved in the cardioprotective effect of adaptation to hypoxia. The role of atrial natriuretic peptide (ANP), erythropoietin, endothelin-1, phosphoinositide 3-kinases (PI3K), protein kinase G (PKG), c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (p38 MAPK) in the protective effect of adaptation to hypoxia requires further research. [ABSTRACT FROM AUTHOR]

C57BL/6 is the most widely used mouse strain in the laboratories. Two substrains of C57BL/6, C57BL/6J (B6J), and C57BL/6N (B6N) are well-known backgrounds for genetic modification and have been shown difference in quite a few tests, including open field test, rotarod test, and Morris water maze. However, difference between these two substrains in olfaction-dependent behaviors remains unknown. Here, we used olfactory two-alternative choice task, which is modified to have two training stages, to evaluate animals' ability in instrumental learning and olfactory association. In the first (rule learning) stage, the mice were trained to use the operant chamber to collect water rewards. An odor cue was provided in the procedure, with no indication about reward locations. In the following (discrimination learning) stage, two odor cues were provided, with each indicating a specific water port. The animals were rewarded upon correct port choices following cue deliveries. We found that during young adulthood (7–10 weeks old), proportionally more B6J than B6N mice were able to pass rule learning (58.3% vs. 29.2%) and ultimately acquire this task (54.2% vs. 25%), with the two substrains showing similar pass rates in discrimination learning (92.9% vs. 85.7%). Surprisingly, at a more mature age (17 weeks old), this substrain difference disappeared. Mature B6N mice had a significant improvement in pass percentages of rule learning and overall task, whereas similar improvement was not observed in the B6J counterparts. Instead, mature B6J mice had an improved speed in rule learning and overall task. We further examined behavioral patterns of 8-week-old B6J and B6N mice in the olfactory habituation or dishabituation test. We observed normal olfactory habituation from subjects of both substrains, with the B6J mice exhibiting stronger investigative responses to newly presented odorants. These results reveal for the first time that B6J and B6N mice are different in acquisition processes of a behavioral task that requires instrumental learning and olfactory association, and that maturation appears to employ different effects on these two substrains during these processes. Furthermore, young adult B6J and B6N mice might be similar in olfactory habituation but different in the olfactory aspects of novelty seeking. [ABSTRACT FROM AUTHOR]

The verification of exposure to nerve agents is a serious challenge, especially in cases of soman (GD) poisoning. Protein adducts are reliable biomarkers, that provide forensic information and evidence during incidents of terrorism or sporadic poisoning. Mass spectrometry, coupled with a proteomics approach, was established for the forensic analysis of GD-based protein adducts. The fragmentation pathways of GD-based protein adducts were investigated for the first time using electrospray ionization tandem mass spectrometry. Three abundant natural loss product ions, [M+2H-54]2+ (loss of two carbon cations), [M+2H-72]2+ (loss of tert -butyl and methyl moieties), and [M+2H-84]2+ (loss of the pinacolyl moieties), were observed in each of the GD-labeled adducts, and the product ions were independent of protein structure and exposure route. A unique mechanism for the formation of product ions involving GD-protein adducts is proposed here. These findings support the development of a simple and precise forensic analysis technique to rapidly verify GD poisoning using these three GD-related product ions. [ABSTRACT FROM AUTHOR]

The piriform cortex (PC) is a major cortical processing center for the sense of smell that receives direct inputs from the olfactory bulb. In mice, the PC consists of three neuronal layers, which are populated by cells with distinct developmental origins. One origin of PC neurons is the pool of Dbx1-expressing neural progenitors located in the ventral pallium at the pallial-subpallial boundary. Since the precise mechanisms of PC neuron development are largely unknown, we sought to define the distribution, timing of neurogenesis, morphology and projection patterns of PC neurons from the Dbx1 lineage. We found that Dbx1-lineage neurons are preferentially distributed in layer 2 and enriched in the ventral portion of the PC. Further, Dbx1 neurons are early-born neurons and contribute to most neuronal subtypes in the PC. Our data also revealed an enrichment of Dbx1-lineage neurons in the ventral anterior PC that project to the orbitofrontal cortex. These findings suggest a specific association between the developmental origin of PC neurons and their neuronal properties. [ABSTRACT FROM AUTHOR]

To date, the largest published studies on knee kinematics using biplane radiography included 74 patients who received knee arthroplasty [[13]] and 49 patients who received ACL-reconstruction [[1]]. Graph Much of what we know, or think we know, about knee kinematics and how injury and surgical intervention affect knee kinematics is based on biomechanical studies of cadavers [[11]]. Anatomic single- and double-bundle ACL reconstruction both restore dynamic knee function: a randomized clinical trial-part II: knee kinematics. [Extracted from the article]

The Lion Forest Garden was originally built in 1342, during Yuan Dynasty, and became one of the most famous gardens in Suzhou. In 2000, it was inscribed in the World Heritage List as an extensive property of the Classical Gardens of Suzhou. The Lion Forest Garden is famous for its stony artificial hills covering more than 4,000 square meters, which were continually built during Yuan, Ming, and Qing Dynasty. However, as a long time passed, stony artificial hills appear damaged showing stone cracking - which could be seen in many places-, gaping, weathering, water erosion, and subsidence. Besides, a new underground line will pass through the road west to the Garden. In 2018 and 2019, the Landscape Architecture Engineering Lab of the Beijing University of Civil Engineering and Architecture collaborated with the Lion Forest Garden Administration on a research to define the strategy to monitor these stony artificial hills. Multiple technologies were used, such as 3D Scanning, Ultrasonic Testing, Side-Scan Sonar, sensors, and so forth. During the monitoring, some technologies worked well while others did not. The paper, based on the mentioned research, will discuss the strategy and technologies used in monitoring historical rockeries, describe the procedure, analyse the outcomes, and find out the reasons causing the unsuccess of some technologies. [ABSTRACT FROM AUTHOR]

Background: The prognostic and clinical significance of single hormone receptor expression in breast cancer has not been clearly established. The goal of this study was to conduct a meta-analysis to compare the clinical outcomes of patients with ER+PR− tumours and ER−PR+ tumours to those of patients with ER+PR+ tumours. Methods: A systematic review of the literature was conducted to identify studies that compared the clinical outcome of patients with ER+PR− tumours or ER−PR+ tumours with those of patients with ER+PR+ tumours. A total of 18 studies met the inclusion criteria and included 217,485 women. Standard methods for meta-analysis were used, including fixed-effect models. Results: Patients with ER+PR− tumours or ER−PR+ tumours had significantly worse DFS (HR 1.60, 95% CI 1.44–1.77 and HR 2.27, 95% CI 1.67–3.09), BCSS (HR 1.43, 95% CI 1.33–1.53 and HR 1.82, 95% CI 1.68–1.98) and OS (HR 1.38, 95% CI 1.28–1.47 and HR 1.48, 95% CI 1.17–1.89) than those of patients with ER+PR+ tumours. In subgroup analyses, patients who had ER+PR− tumours experienced a higher risk of recurrence than patients with ER+PR+ tumours in the HER2− (HR 1.57, 95% CI 1.32–1.87), LN − (HR 2.07, 95% CI 1.44–2.86) and endocrine therapy (HR 1.65, 95% CI 1.45–1.89) subgroup. Patients who had HER2− and ER−PR+ tumours had an increased risk of recurrence compared with patients who had HER2− and ER+PR+ tumours (HR 3.10, 95% CI 1.92–5.10). Conclusions: Among patients with hormone receptor-positive breast cancer, patients with either ER+PR− tumours or ER−PR+ tumours have a higher risk of recurrence and a shorter survival time than those with ER+PR+ tumours. Patients with both types of breast cancer need additional or better treatments. [ABSTRACT FROM AUTHOR]

Background: Parkinson's disease (PD) features the motor control deficits resulting from irreversible, progressive degeneration of dopaminergic (DA) neurons of the nigrostriatal pathway. Although intracerebral transplantation of human fetal ventral mesencephalon (hfVM) has been proven effective at reviving DA function in the PD patients, this treatment is clinically limited by availability of hfVM and the related ethical issues. Homologous tissues to hfVM, such as porcine fetal ventral mesencephalon (pfVM) thus present a strong clinical potential if immune response following xenotransplantation could be tamed. Olfactory ensheathing cells (OECs) are glial cells showing immunomodulatory properties. It is unclear but intriuging whether these properties can be applied to reducing immune response following neural xenotransplantation of PD. Methods: To determine whether OECs may benefit neural xenografts for PD, different compositions of grafting cells were transplanted into striatum of the PD model rats. We used apomorphine‐induced rotational behavior to evaluate effectiveness of the neural grafts on reviving DA function. Immunohistochemistry was applied to investigate the effect of OECs on the survival of neuroxenografts and underlying mechanisms of this effect. Results: Four weeks following the xenotransplantation, we found that the PD rats receiving pfVM + OECs co‐graft exhibited a better improvement in apomorphine‐induced rotational behavior compared with those receiving only pfVM cells. This result can be explained by higher survival of DA neurons (tyrosine hydroxylase immunoreactivity) in grafted striatum of pfVM + OECs group. Furthermore, pfVM + OECs group has less immune response (CD3+ T cells and OX‐6+ microglia) around the grafted area compared with pfVM only group. These results suggest that OECs may enhance the survival of the striatal xenografts via dampening the immune response at the grafted sites. Conclusions: Using allogeneic OECs as a co‐graft material for xenogeneic neural grafts could be a feasible therapeutic strategy to enhance results and applicability of the cell replacement therapy for PD. [ABSTRACT FROM AUTHOR]

In maize soybean intercropping-system maize plants significantly increase the shade density at soybean canopy, and few people studied the threshold level of shade for sustainable production of soybean in this system. This experiment was started to determine the effect of four different shade treatments T75 (75%); T50 (50%); T25 (25%); T0 (0%, control) on morphology, physiology and yield of soybean plants. Relative to T75, treatments T25 and T0 significantly increased the stem diameter and stem breaking strength while plant height was decreased. The chlorophyll a, chlorophyll b, and chlorophyll a + b, photosynthetic and chlorophyll fluorescence characteristics were improved as shade decreased, and maximum values were observed in T25 and T0. Similarly, enzymatic activity of Rubisco was accelerated from T75 to T0. However, genes related to sucrose synthesis (SS and SPS) were down-regulated by increasing shade (T75). Importantly, non-significant differences were measured for seed-yield between T25 and T0, and the plants of soybean under T25 produced 88% of T0 yield. Overall, these results implied that agronomist should develop an appropriate intercropping planting pattern where the maximum shade density ranges from 20 to 30 % to obtain higher seed yield of soybean crop under intercropping-system. [ABSTRACT FROM AUTHOR]

Presents a study which calculated acoustic power flow in a lithium niobium trioxide single crystal to find the optimal crystal cutting orientation and the wave of propagation direction for the efficient excitation of acoustic waves in the crystal. Wave propagation in lithium niobium trioxide; Crystal orientation.

A double-layer grid space structure is a conventional long span structure used where large column-free areas are required. Due to its’ large indeterminacy and the redundancy of its structural configuration, it is normally considered in design practice, that progressive collapse will not be triggered when the loss of an individual member occurs. However, research and several prior accidents have shown that progressive collapse could occur following the loss of some critical members when the structures are subject to abnormal loading such as heavy snow. To investigate the structural behavior of this type of structure, a 3D finite element model of a double-layer space structure grid was built by the authors, several collapse scenarios have been investigated using an implicit method which follows the alternative path method defined in GSA. In addition, case studies have been made using the explicit method which is to simulate the whole process of the structural collapse. In the analysis, different members failure or support collapses were studied. The response of the structure was investigated and the correspondent potential of progressive collapse was discussed in detail. Methods to mitigate the progressive collapse of this type of space structure have also been recommended. [ABSTRACT FROM AUTHOR]

Purpose: To compare the different types of ACL reconstructions in terms of knee dynamic laxity evaluated by acceleration.Methods: Sixteen fresh frozen cadaveric knees were used. Pivot shift test was manually performed while monitoring the tibial acceleration by use of a triaxial accelerometer. The test was repeated before and after the ACL resection and reconstruction. Three types of ACL reconstruction were tested: (1) Anatomic Single-Bundle reconstruction (n = 8), the graft was placed at the center of the ACL footprint for the both femoral and tibial sides (tunnel diameter: 8mm); (2) Conventional Single-Bundle reconstruction (n = 8), the graft was placed from the tibial PL footprint to femoral high AM position (tunnel diameter: 8mm) and (3) Anatomic Double-Bundle reconstruction (n = 8). The acceleration in each of three x-y-z directions and the overall magnitude of acceleration was calculated to evaluate dynamic rotational laxity and compared between different ACL reconstructions.Results: The overall magnitude of acceleration was significantly different between ACL intact and deficient knees (p < 0.0001). The acceleration was reduced by the DB ACL reconstruction to the intact level (n.s.), but the two SB ACL reconstruction failed to achieve the intact level of the acceleration (p = 0.0002non-anatomic SB, p < 0.0001 anatomic SB).Conclusion: The anatomic DB reconstruction better restores dynamic rotational laxity when compared to the SB ACL reconstructions no matter if the tunnel placement was anatomic. The anatomic DB reconstruction better restores dynamic rotational laxity when compared to both anatomic and non-anatomic SB ACL reconstruction. For this reason anatomic DB ACL reconstruction is recommended for cases where rotational laxity is an issue. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the diagnostic yield of prenatal whole exome sequencing (WES) for monogenic disorders in fetuses with structural malformations and normal results on cytogenetic testing, and to describe information on pathogenic variants that is provided by WES.Methods: Karyotyping, chromosomal microarray analysis (CMA) and WES were performed sequentially on stored samples from a cohort of 3949 pregnancies with fetal structural abnormalities detected on ultrasound and/or magnetic resonance imaging, referred between January 2011 and December 2015. Diagnostic rates of the three techniques were investigated overall, for phenotypic subgroups and for proband-only vs fetus-mother-father samples. Information on pathogenic variants was identified by WES.Results: Overall, 18.2% (720/3949) of fetuses had an abnormal karyotype. Pathogenic copy number variants were detected on CMA in 8.2% (138/1680) of fetuses that had a normal karyotype result. WES performed on a subgroup of 196 fetuses with normal CMA and karyotype results revealed the putative genetic variants responsible for the abnormal phenotypes in 47 cases (24%). The molecular diagnosis rates for fetus-mother-father and proband-only samples were 26.5% (13/49) and 23.1% (34/147), respectively. Variants of uncertain significance were detected in 12.8% (25/196) of fetuses, of which 22 were identified in the fetal proband-only group (15%; 22/147) and three in the fetus-mother-father group (6.1%; 3/49). The incidental finding rate was 6.1% (12/196).Conclusions: WES is a promising method for the identification of genetic variants that cause structural abnormalities in fetuses with normal results on karyotyping and CMA. This enhanced diagnostic yield has the potential to improve the clinical management of pregnancies and to inform better the reproductive decisions of affected families. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

The genus Echinochloa (Poaceae) includes numerous problematic weeds over a wide range of ecoregions in the world. To date, molecular markers for species identification and assessing phylogenetic relationship are still limited in the genus Echinochloa. In this study, we developed seven chloroplast molecular markers based on divergent chloroplast regions of E. crus-galli and E. oryzicola. Furthermore, Marker #1 ( psbA) was examined in more than 200 Echinochloa accessions and a phylogenetic tree grouped these Echinochloa accessions into four clades. Additionally, two different E. crus-galli varieties ( E. crus-galli var. crus-galli, E. crus-galli var. praticola) and E. colona were successfully distinguished by this marker. The developed molecular markers contribute to better identification of Echinochloa taxa. [ABSTRACT FROM AUTHOR]

Porcine circovirus type 3 ( PCV3) was detected in Shandong, China. One hundred and thirty-two of 222 (59.46%) samples were PCV3 positive, while 52 of 132 (39.39%) samples were co-infected with PCV2. There were no clinical signs of infection in either multiparous sows or live-born infants. Two strains of PCV3 were indentified from natural stillborn foetuses. Phylogenetic analysis showed the two strains of PCV3 are 96% identical to the known PCV3/Pig/ USA (KX778720.1, KX966193.1 and KX898030.1) and closely related to Barbel Circovirus. Further studies of the epidemiology of PCV3 and the co-infection with PCV2 are needed. [ABSTRACT FROM AUTHOR]

The effect of stirring rates in anodic area of sediment microbial fuel cell on its operating performance, in terms of variations in power generation and sludge properties, was investigated in this work. The power density under 100 r/min stirring rate amounted to the highest peak value (98.8 mW/m2for the 9th cycle). The volume average sizes of sludge flocs decreased with increasing the stirring rates, but the content of extracellular polymeric substances of sludge increased. According to cyclic voltammetry examination, significant improvement in electrochemical activity with microorganism growth was due to some kinds of mediating compounds produced in cell-associated form. [ABSTRACT FROM PUBLISHER]

Reusable ZnO/Zn-Cr hydrotalcite-like anionic clays (ZnO/Zn-Cr HACs) were synthesized by a co-precipitation method and characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, N adsorption-desorption analysis, elemental mapping patterns, scanning electronic microscope, and UV-Vis diffuse reflectance spectra. Its adsorption and photocatalytic activity towards organic pollutant (congo red as a model pollutant) were evaluated. The Langmuir isotherm was used to fit the equilibrium experiments. Saturated adsorption capacity of ZnO/Zn-Cr HACs was 426.29 mg g at 308 K. The model pollutant exhibited fast and highly efficient removal from aqueous solution by ZnO/Zn-Cr HACs under simulated solar light irradiation. The experiments of cycles demonstrated that there was no evident change in the removal efficiency of Congo red (CR) solution by ZnO/Zn-Cr HACs the fifth time under simulated solar light irradiation, which indicates that ZnO/Zn-Cr HACs can be reused and will be favorable for effective elimination of toxic organic compounds in wastewater. Therefore, it is expected that ZnO/Zn-Cr HACs with layered structures and high surface areas can be potentially used as effective and reusable materials for large-scale environmental purification. [ABSTRACT FROM AUTHOR]

High-risk human papillomaviruses (HPVs) are highly prevalent worldwide, and HPV genotype distribution varies regionally. Molecular surveys of HPVs are important for effective HPV control and prevention. Fifteen high-risk HPV strains (16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 68) and six low-risk HPV strains (HPV6, 11, 42, 43, 44, CP8304) were detected by cervical cytology from 10 501 subjects. High-risk HPVs, low-risk HPVs, and both high- and low-risk HPVs were detected in 14·5%, 2·8%, and 2·4% of cases, respectively. Of 1782 subjects with high-risk HPV infection, 75·5%, 18·1%, and 6·4% were infected with one, two, and ⩾3 strains of high-risk HPVs, respectively. HPV52, HPV16, and HPV58 were the top three most dominant high-risk HPV genotypes in our population with positivity rates of 23·0%, 17·7% and 16·9%, respectively. Multiple infection was common, with significantly higher co-infection rates of HPV58/HPV33 (12·9%) and HPV58/HPV52 (11·3%). Further data comparisons showed that HPV genotype distribution varied markedly between domestic and international regions. In conclusion, a monolithic vaccination strategy is obviously impractical, and regional HPV surveillance is essential to optimize current HPV control and prevention. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the clinical performance of non-invasive prenatal testing (NIPT) in detecting fetal copy number variants (CNVs).Methods: NIPT of cell-free fetal DNA was performed retrospectively, using stored maternal plasma, at an average gestational age of 21.1 weeks in 117 pregnant women who had previously undergone invasive prenatal testing for chromosome microarray analysis (CMA). Among the fetal samples tested by CMA, 18 had positive results (CNVs > 1 megabase (Mb)) and 99 had negative results (CNVs < 1 Mb or without CNVs detected). The results of NIPT and CMA were then compared.Results: In the 11 CMA-positive samples with CNVs > 5 Mb, the detection rate of CNVs was 90.9%; the one case missed by NIPT had a fetal fraction of 4.7%. For the other seven CMA-positive samples with CNVs < 5 Mb, the detection rate was 14.3%; only one case with a 2.82-Mb duplication was detected, with a fetal fraction of 26.7%. For 35.7% (5/14) of CNVs detected by both NIPT and CMA, the differences in fragment length were within ± 1 Mb. In this study, the overall sensitivity and specificity of NIPT for detecting CNVs > 1 Mb were 61.1% and 95.0%, respectively, with a false-positive rate of 5.0%.Conclusions: Our results demonstrate that NIPT for common aneuploidies can detect fetal CNVs > 5 Mb with high sensitivity, provided that fetal fraction is high enough, without increasing sequencing depth. The detection power of NIPT is determined mostly by fetal fraction and CNV size. A positive NIPT screening result for CNVs must be interpreted with caution and validated by additional diagnostic study. [ABSTRACT FROM AUTHOR]

We report ultrafast relativistic electron diffraction operating at the megahertz repetition rate where the electron beam is produced in a superconducting radio-frequency (rf) photoinjector. We show that the beam quality is sufficiently high to provide clear diffraction patterns from gold and aluminium samples. With the number of electrons, several orders of magnitude higher than that from a normal conducting photocathode rf gun, such high repetition rate ultrafast MeV electron diffraction may open up many new opportunities in ultrafast science. [ABSTRACT FROM AUTHOR]

Purpose: The goal of individualized anatomic anterior cruciate ligament reconstruction (ACL-R) is to reproduce each patient's native insertion site as closely as possible. The amount of the native insertion site that is recreated by the tunnel aperture area is currently unknown, as are the implications of the degree of coverage. As such, the goals of this study are to determine whether individualized anatomic ACL-R techniques can maximally fill the native insertion site and to attempt to establish a crude measure to evaluate the percentage of reconstructed area as a first step towards elucidating the implications of complete footprint restoration. Methods: This is a prospective pilot study of 45 patients who underwent primary single-bundle anatomic ACL-R from May 2011 to April 2012. Length and width of the native insertion site were measured intraoperatively. Using published guidelines, reconstruction technique and graft choice were determined to maximize the percentage of reconstructed area. Native femoral and tibial insertion site area and femoral tunnel aperture area were calculated using the formula for area of an ellipse. On the tibial side, tunnel aperture area was calculated with respect to drill diameter and drill guide angle. Percentage of reconstructed area was calculated by dividing total tunnel aperture area by the native insertion site area. Results: The mean areas for the native femoral and tibial insertion sites were 83 ± 20 and 125 ± 20 mm, respectively. The mean tunnel aperture area for the femoral side was 65 ± 17, and 86 ± 17 mm for the tibial tunnel aperture area. On average, percentage of reconstructed area was 79 ± 13 % for the femoral side, and 70 ± 12 % for the tibial side. Conclusion: Anatomic ACL-R does not restore the native insertion site in its entirety. Percentage of reconstructed area serves as a rudimentary tool for evaluating the degree of native insertion site coverage using current individualized anatomic techniques and provides a starting point from which to evaluate the clinical significance of complete footprint restoration. Level of evidence: IV. [ABSTRACT FROM AUTHOR]

Objective: To retrospectively evaluate the radiopathological features of adult metanephric adenoma (MA) and explore whether MA can be differentiated on CT images, including the basis of their morphological features and enhancement patterns. Methods: 18 consecutive MA cases (age range, 18-66 years; 9 males and 9 females) were pathologically proven and recruited in our study between January 2004 and June 2014. Unenhanced and contrast-enhanced CT were performed and correlated with corresponding pathological findings to differentiate between MA and other renal tumours. The enhancement pattern, lesion contour and presence of calcifications were evaluated. RResults: On unenhanced CT scan, the most common (n =15, 83.3%) CT imaging characteristics were the presence of homogeneity and well-defined solid renal masses; the minority (n=3, 16.7%) were heterogeneous or centrally located low-attenuation masses. Contrast-enhanced CT image revealed hypoattenuating heterogeneous masses with varying degrees of contrast enhancement in 16 (88.9%) cases, in contrast to those without increased attenuation in 2 (11.1%) cases. Scattered calcification was found only in one case (5.6%). Pathological results revealed that a total of 6 (33.3%) cases had concomitant malignant carcinoma components; 2 (11.1%) patients had malignant MA; and pure MA was found in 10 cases, with a surprisingly high proportion of malignant tumours. Conclusion: The positive-predictive values of "high" enhancement seemed relatively characteristic for the diagnosis of malignant and composite MA. Advances in knowledge: Radiopathological features of adult MA and exploring whether MA can be differentiated on CT images, including the basis of their morphological features and enhancement patterns. [ABSTRACT FROM AUTHOR]

Two isomeric Mn(II) complexes, [Mn(IDP)SO · 2HO] ( I) and {[Mn(IDP)SO · HO] · HO} ( II), have been prepared by solvo-thermal reactions of imidazo-[4,5-f]-1,10-phenanthroline (IDP) ligand with manganese sulfate. The crystal structures of IDP, complexes I and II are characterized by single-crystal X-ray diffusion analyses (CIF files CCDC nos. 988128 (IDP), 988129 ( I), and 988130 ( II)). The structural analyses show that there are H-bonds and π-π stacking interactions resulting in the 3D supramolecular structure for IDP. Complex I exhibits 1D chain-like structure featuring the left- and right-handed helical chains, while in II, the 1D structure is a ladder-like structure. The π-π stacking interactions take an important role in the formation of supramolecule structures for complexes HL, I, II due to the large conjugated system of IDP ligand. The IR and UV-Vis absorption spectra of complexes I and II exhibit the difference, but the liquid-state photoluminescence of I and II is similar attributing to the intraligand π-π* transition. [ABSTRACT FROM AUTHOR]

Long-acting injectable formulations of antipsychotics have been an important treatment option to increase the compliance of the patient with schizophrenia by monitoring drug administration and identifying medication noncompliance and to improve the long-term management of schizophrenia. Risperidone, a serotoninergic 5-HT2 and dopaminergic D2 receptor antagonist, was developed to be a long-acting sustained-release formulation for the treatment of schizophrenia. In this study, 12-week subchronic toxicity study of risperidone-loaded microspheres (RMs) in rats by intramuscular injection with an 8-week recovery phase was carried out to investigate the potential subchronic toxicity of a novel long-acting sustained-release formulation. The results indicated that the dosage of 10–90 mg/kg of RM for 2 weeks did not cause treatment-related mortality. The main drug-related findings were contributed to the dopamine D2 receptor and α1-adrenoceptor antagonism of risperidone such as elevation of serum and pituitary prolactin levels and ptosis and changes in reproductive system (uterus, ovary, vagina, mammary gland, testis, seminal vesicle, epididymis, and prostate). In addition, foreign body granuloma in muscle at injection sites caused by poly-lactide-co-glycolide was observed. At the end of the recovery phase, these changes mostly returned to normal. The results indicated that RM had a good safety profile in rats. [ABSTRACT FROM AUTHOR]

The piriform cortex (PCX) is the largest component of the olfactory cortex and is hypothesized to be the locus of odor object formation. The distributed odorant representation found in PCX contrasts sharply with the topographical representation seen in other primary sensory cortices, making it difficult to test this view. Recent work in PCX has focused on functional characteristics of these distributed afferent and association fiber systems. However, information regarding the efferent projections of PCX and how those may be involved in odor representation and object recognition has been largely ignored. To investigate this aspect of PCX, we have used the efferent pathway from mouse PCX to the orbitofrontal cortex (OFC). Using double fluorescent retrograde tracing, we identified the output neurons (OPNs) of the PCX that project to two subdivisions of the OFC, the agranular insula and the lateral orbitofrontal cortex (AI-OPNs and LO-OPNs, respectively). We found that both AI-OPNs and LO-OPNs showed a distinct spatial topography within the PCX and fewer than 10% projected to both the AI and the LO as judged by double-labeling. These data revealed that the efferent component of the PCX may be topographically organized. Further, these data suggest a model for functional organization of the PCX in which the OPNs are grouped into parallel output circuits that provide olfactory information to different higher centers. The distributed afferent input from the olfactory bulb and the local PCX association circuits would then ensure a complete olfactory representation, pattern recognition capability, and neuroplasticity in each efferent circuit. [ABSTRACT FROM AUTHOR]

Background and Purpose Previously, a systems pharmacology model was developed characterizing drug effects on the interrelationship between mean arterial pressure ( MAP), cardiac output ( CO) and total peripheral resistance ( TPR). The present investigation aims to (i) extend the previously developed model by parsing CO into heart rate ( HR) and stroke volume ( SV) and (ii) evaluate if the mechanism of action ( MoA) of new compounds can be elucidated using only HR and MAP measurements. Experimental Approach Cardiovascular effects of eight drugs with diverse MoAs (amiloride, amlodipine, atropine, enalapril, fasudil, hydrochlorothiazide, prazosin and propranolol) were characterized in spontaneously hypertensive rats ( SHR) and normotensive Wistar- Kyoto ( WKY) rats following single administrations of a range of doses. Rats were instrumented with ascending aortic flow probes and aortic catheters/radiotransmitters for continuous recording of MAP, HR and CO throughout the experiments. Data were analysed in conjunction with independent information on the time course of the drug concentration following a mechanism-based pharmacokinetic-pharmacodynamic modelling approach. Key Results The extended model, which quantified changes in TPR, HR and SV with negative feedback through MAP, adequately described the cardiovascular effects of the drugs while accounting for circadian variations and handling effects. Conclusions and Implications A systems pharmacology model characterizing the interrelationship between MAP, CO, HR, SV and TPR was obtained in hypertensive and normotensive rats. This extended model can quantify dynamic changes in the CVS and elucidate the MoA for novel compounds, with one site of action, using only HR and MAP measurements. Whether the model can be applied for compounds with a more complex MoA remains to be established. [ABSTRACT FROM AUTHOR]

High-performance thermoelectric BiCuSeO ceramics have been prepared by solid state reaction combined with plasma activated sintering (PAS). Phase compositional and microstructural studies indicate composites having refined grain sizes (600-700 nm) with nanostructured ZnSe secondary phase. Our results reveal that Zn doping can lead to a large change in the carrier concentration (from 0.036 × 1020 cm−3 to 1.50 × 1020 cm−3), thus resulting in an increased electrical conductivity of three orders of magnitude at room temperature. The highest power factor of 4.21 µWcm−1K−2 at 873 K has been achieved by 10% Zn doping. On the other hand, the lattice thermal conductivity has been suppressed significantly due to refined grains, point defects and the nano-inclusions of ZnSe phase. The dimensionless figure of merit ( ZT) could reach up to 0.90 at 873 K in the BiCuSeO oxyselenides by the 10% Zn doping, which makes Zn-doped BiCuSeO to be a promising candidate for thermoelectric applications. [ABSTRACT FROM AUTHOR]

Chromosome microarray analysis ( CMA) has proven to be a powerful tool in postnatal patients with intellectual disabilities, and it is increasingly used in prenatal diagnosis. However, its diagnostic capabilities in prenatal diagnosis vary, and clinical experiences have failed to establish a consensus regarding CMA indications, the design and resolution of microarrays, and the notification and interpretation of copy number variations ( CNVs). We present our 5 years of clinical experience using whole-genome high-resolution single nucleotide polymorphism ( SNP) arrays to investigate 446 fetuses that had structural malformations detected with ultrasound but for which standard karyotyping analysis showed normal karyotypes. CMA revealed genomic CNVs in 323 (72.4%) cases and clinically significant CNVs in 11.4% of the fetuses (51/446), including 2 cases of uniparental disomy ( UPD) as well as 1 case of cryptic mosaic monosomy of chromosome X. Variants of unknown significance ( VOUS) existed in 2.0% of the tested fetuses (9/446). Our results demonstrate the value of whole-genome high-resolution SNP arrays in fetuses with congenital malformations and give a higher detection rate of clinically significant genomic imbalance, especially for detecting UPD. Sufficient communication between technicians and genetic counselors, along with parental testing and comparison with data from in-house or international sources, can significantly reduce VOUS. [ABSTRACT FROM AUTHOR]

The relationship between optical behaviour and microstructure of pearl was studied by laser scanning confocal microscopy, high resolution scanning electron microscopy and atomic force microscopy. There are three optical effects in pearls, namely, the reflection-diffraction effect, a chromatic diffusion halo and the whispering gallery effect. From the structure observation for pearls, we proposed that the first optical effect exhibited by pearls is dominated by the surface diffuse reflection. In addition, the multilayer interference and diffraction have little contribution. With delicate observation for the structure of pearl by an atomic force microscope, it is revealed that the polygon platelets of pearl are not single crystals but nanograins of aragonite in the network of organic matrix, which is responsible for the chromatic diffusion halo. As for the third optical effect, it originates from the stratification structure, which is composed of aragonite platelets. When the light falls on the surface of the pearl, it will travel along the laminations of its structure rather than through the whole pearl, so the rim of the pearl is bright even if no light falls on the surface directly. [ABSTRACT FROM AUTHOR]

Malignant transformation of normal hematopoietic transplants induced by residual leukemia cells is considered as a pivotal mechanism of donor cell leukemia (DCL). The effects of leukemia cell-derived microvesicles (MVs) in this transformation were examined. We found that MVs derived from K562 leukemia cells contained the breakpoint cluster region-Abelson leukemia gene human homolog 1 (BCR-ABL1) mRNA. Following incubation with BCR-ABL1-positive MVs, mononuclear cells derived from normal transplants exhibited a leukemia-like malignant phenotype both in vitro and in vivo. Horizontal transfer of BCR-ABL1 mRNA from MVs into the recipient cells was critical to the transformation. Relative genomic instability was observed and considered the main mechanism in the recipient cells. MVs contributed to genomic instability by two distinct pathways: via consequent overexpression of activation-induced cytidine deaminase and reactive oxygen species, which mediated DNA breakage and recombination; and via upregulation of methyltransferases and global DNA hypermethylation. We demonstrated that BCR-ABL1-positive MVs could initiate malignant transformation of normal hematopoietic transplants through genomic instability, which might serve as a convenient and operable model for investigating leukemogenesis, especially for DCL. Furthermore, MVs themselves could act as an early warning indicator and a novel tool to detect and prevent the occurrence of DCL. [ABSTRACT FROM AUTHOR]

Malignant transformation of normal hematopoietic transplants induced by residual leukemia cells is considered as a pivotal mechanism of donor cell leukemia (DCL). The effects of leukemia cell-derived microvesicles (MVs) in this transformation were examined. We found that MVs derived from K562 leukemia cells contained the breakpoint cluster region-Abelson leukemia gene human homolog 1 (BCR-ABL1) mRNA. Following incubation with BCR-ABL1-positive MVs, mononuclear cells derived from normal transplants exhibited a leukemia-like malignant phenotype both in vitro and in vivo. Horizontal transfer of BCR-ABL1 mRNA from MVs into the recipient cells was critical to the transformation. Relative genomic instability was observed and considered the main mechanism in the recipient cells. MVs contributed to genomic instability by two distinct pathways: via consequent overexpression of activation-induced cytidine deaminase and reactive oxygen species, which mediated DNA breakage and recombination; and via upregulation of methyltransferases and global DNA hypermethylation. We demonstrated that BCR-ABL1-positive MVs could initiate malignant transformation of normal hematopoietic transplants through genomic instability, which might serve as a convenient and operable model for investigating leukemogenesis, especially for DCL. Furthermore, MVs themselves could act as an early warning indicator and a novel tool to detect and prevent the occurrence of DCL. [ABSTRACT FROM AUTHOR]

Purpose: In August 2011, orthopaedic surgeons from more than 20 countries attended a summit on anatomic anterior cruciate ligament (ACL) reconstruction. The summit offered a unique opportunity to discuss current concepts, approaches, and techniques in the field of ACL reconstruction among leading surgeons in the field. Methods: Five panels (with 36 panellists) were conducted on key issues in ACL surgery: anatomic ACL reconstruction, rehabilitation and return to activity following anatomic ACL reconstruction, failure after ACL reconstruction, revision anatomic ACL reconstruction, and partial ACL injuries and ACL augmentation. Panellists' responses were secondarily collected using an online survey. Results: Thirty-six panellists (35 surgeons and 1 physical therapist) sat on at least one panel. Of the 35 surgeons surveyed, 22 reported performing 'anatomic' ACL reconstructions. The preferred graft choice was hamstring tendon autograft (53.1 %) followed by bone-patellar tendon-bone autograft (22.8 %), allograft (13.5 %), and quadriceps tendon autograft (10.6 %). Patients generally returned to play after an average of 6 months, with return to full competition after an average of 8 months. ACL reconstruction 'failure' was defined by 12 surgeons as instability and pathological laxity on examination, a need for revision, and/or evidence of tear on magnetic resonance imaging. The average percentage of patients meeting the criteria for 'failure' was 8.2 %. Conclusions: These data summarize the results of five panels on anatomic ACL reconstruction. The most popular graft choice among surgeons for primary ACL reconstructions is hamstring tendon autograft, with allograft being used most frequently employed in revision cases. Nearly half of the surgeons surveyed performed both single- and double-bundle ACL reconstructions depending on certain criteria. Regardless of the technique regularly employed, there was unanimous support among surgeons for the use of 'anatomic' reconstructions using bony and soft tissue remnant landmarks. Level of evidence: V. [ABSTRACT FROM AUTHOR]

Purpose: To describe the concept of individualized anatomic anterior cruciate ligament (ACL) reconstruction. Methods: The PubMed/Medline database was searched using keywords pertaining to ACL reconstruction. Relevant articles were reviewed in order to summarize important concepts of individualized surgery in ACL reconstruction. Surgical experiences with case examples are also highlighted. Results: Individualized ACL surgery allows for the customization of surgery to each individual patient. Accounting for graft selection and other characteristics such as anatomy, lifestyle and activity preferences may provide the patient with the best potential for a successful outcome. The surgeon should be comfortable with a variety of graft harvests and surgical techniques when practicing individualized surgery. Conclusion: Individualized anatomic ACL reconstruction is founded on the objective evaluation of functional anatomy and individual characteristics, thereby restoring the ACL as closely as possible to the native anatomy and function. The adoption and subsequent use of individualized surgery may facilitate improved clinical as well as objective outcomes, particularly in the long term. Level of evidence: V. [ABSTRACT FROM AUTHOR]

BACKGROUND Although black patients experience worse outcomes after treatment for squamous cell carcinoma of the head and neck (HNSCC), these conclusions were based on populations in which blacks comprised a minority of patients. The objective of the current study was to determine the impact of race on outcomes in patients with HNSCC who received radiotherapy at an institution in which blacks comprised the majority of patients. METHODS In this retrospective cohort study, the authors reviewed 366 black patients and 236 white patients who had nonmetastatic HNSCC for which they received radiotherapy between 1990 and 2012. The primary study outcome measures were locoregional control, freedom from distant metastasis, progression-free survival, and overall survival. RESULTS The median follow-up was 18.3 months for all patients. The 2-year locoregional control rate was 71.9% for black patients compared with 64.2% for white patients (hazard ratio, 0.72; P = .03). There was no difference between blacks and whites regarding 2-year freedom from distant metastasis, progression-free survival, or overall survival. Among the patients who had stage III through IVB disease, blacks and whites had similar outcomes. On multivariate analysis, race was not statistically significant for locoregional control, freedom from distant metastasis, progression-free survival, or overall survival. Despite these similar outcomes, black patients had worse socioeconomic factors and increased comorbidities but had similar treatment compliance compared with white patients. CONCLUSIONS With more adverse prognostic factors, black patients experienced oncologic outcomes similar to the outcomes of white patients after receiving radiotherapy for HNSCC. The current data suggest that centers that treat large percentages of minority patients who receive radiotherapy for HNSCCs may overcome existing health care disparities through improved treatment compliance. Cancer 2014;120:244-252. © 2013 American Cancer Society. [ABSTRACT FROM AUTHOR]

Purpose/Objective(s): To determine if intensity modulated radiation therapy (IMRT) in the post-operative setting for gastric cancer was associated with reduced toxicity compared to 3D conformal radiation therapy (3DCRT). Materials/Methods: This retrospective study includes 24 patients with stage IB-IIIB gastric cancer consecutively treated from 2001–2010. All underwent surgery followed by adjuvant chemoradiation. Concurrent chemotherapy consisted of 5-FU/leucovorin (n = 21), epirubicin/cisplatin/5FU (n = 1), or none (n = 2). IMRT was utilized in 12 patients and 3DCRT in 12 patients. For both groups, the target volume included the tumor bed, anastomosis, gastric stump, and regional lymphatics. Results: Median follow-up for the entire cohort was 19 months (range 0.4–8.5 years), and 49 months (0.5–8.5 years) in surviving patients. The 3DCRT group received a median dose of 45 Gy, and the IMRT group received a median dose of 50.4 Gy (p = 0.0004). For the entire cohort, 3-year overall survival (OS) was 40% and 3-year disease free survival (DFS) was 41%. OS and DFS did not differ significantly between the groups. Acute toxicity was similar. Between 3DCRT and IMRT groups, during radiotherapy, median weight lost (3.2 vs. 3.3 kg, respectively; p = 0.47) and median percent weight loss were similar (5.0% vs. 4.3%, respectively; p = 0.43). Acute grade 2 toxicity was experienced by 8 patients receiving 3DCRT and 11 receiving IMRT (p = 0.32); acute grade 3 toxicity occurred in 1 patient receiving 3DCRT and none receiving IMRT (p = 1.0). No patients in either cohort experienced late grade 3 toxicity, including renal or gastrointestinal toxicity. At last follow up, the median increase in creatinine was 0.1 mg/dL in the IMRT group and 0.1 mg/dL in the 3DCRT group (p = 0.78). Conclusion: This study demonstrates that adjuvant chemoradiation for gastric cancer with IMRT to 50.4 Gy was well-tolerated and compared similarly in toxicity with 3DCRT to 45 Gy. [ABSTRACT FROM AUTHOR]

Macroalgal blooms have occurred worldwide frequently in coastal areas in recent decades, which dramatically modify phosphorus (P) cycle in water column and the sediments. Rongcheng Swan Lake Wetland, a coastal wetland in China, is suffering from extensive macroalgal blooms. In order to verify the influence of macroalgal growth on sediment P release, the sediments and filamentousChaetomorphaspp. were incubated in the laboratory to investigate the changes of water quality parameters, P levels in overlying water, and sediments during the growth period. In addition, algal biomass and tissue P concentration were determined. In general,Chaetomorphabiomasses were much higher in high P treatments than in low P treatments. Compared with algae+low P water treatment, the addition of sediments increased the algal growth rate and P accumulation amount. During the algal growth, water pH increased greatly, which showed significant correlation with algal biomass in treatments with high P (P < 0.05). P fractions in the sediments showed that Fe/Al–P and organic P concentrations declined during the algal growth, and great changes were observed in algae+low P water+sediment treatment for both. As a whole, the sediments can supply P forChaetomorphagrowth when water P level was low, and the probable mechanism was the release of Fe/Al–P at high pH condition induced by intensiveChaetomorphablooms. [ABSTRACT FROM PUBLISHER]

For the orthopedic sports medicine physician soft tissue injuries often present the greatest clinical problems. Not only do many of the most frequently injured tissues, such as the cruciate ligaments and articular cartilage, have very limited capabilities for spontaneous repair, but they also respond poorly to surgical or nonsurgical intervention. In this article we try to define the role of growth factors in these conditions and to outline concepts for future treatment based upon modulation of the native repair response. We suggest that gene transfer could improve the management of such injuries, particularly when used as vehicles for the targeted delivery of growth factors. The concept of gene therapy in orthopedic sports medicine can be extended to include disorders that present as laxity or mechanical weakness of ligaments. We speculate that subtle genetic differences between individuals may account for those who appear to be injury prone. In these cases it is likely that genes encoding the structural macromolecules of the matrix are defective. Local gene supplementation in such cases could be useful in the future. [ABSTRACT FROM AUTHOR]

The role of proprioception as a protective mechanism has gained interest in recent years. From the clinical standpoint, several studies have dealt with ways to enhance proprioception following surgery and during rehabilitation. If kinesthesia (ability to detect passive motion) can be enhanced as a consequence of long-term athletic training, such training must be included as a part of the rehabilitation process to protect the patient from reinjury. Consequently, the purpose of this study was to compare the kinesthetic knee pattern between trained gymnasts and healthy nongymnasts. The proprioception testing device (PTD) was used to evaluate knee kinesthesia. From 45 degrees of flexion, the knee was passively extended with the PTD. The device was stopped by the subject when this passive motion was detected. Fifteen healthy college-age female gymnasts (mean age 19.3 years) and 30 normal volunteers (mean age 20.7 years) comprised our study sample. A one-way analysis of variance (ANOVA) was used to compare the mean values of the dominant gymnastic knee to the dominant knee in the control group. Results revealed statistically significant mean differences between the trained gymnastic group and the untrained control group (F1.34(.95) = 7.17, P = 0.011). The results of this study suggest that extensive training has a positive influence on knee kinesthesia in addition to increasing muscle tone. According to the findings of this and other studies, highly trained athletes possess enhanced neurosensory pathways which are speculated to develop as a result of long-term athletic training. Although definite conclusions cannot be made from our investigation, prospective studies can determine the true role of athletic training in proprioceptive patterns. [ABSTRACT FROM AUTHOR]

In this study, the geometric and mechanical properties of the long head of the biceps tendon were determined in order to elucidate its role in shoulder stability. We used a laser-micrometer system to measure the cross-sectional area and shape of seven fresh-frozen tendons at three levels: proximal, middle, and distal levels. The cross-sectional areas were found to be 22.7 +/- 9.3 mm2, 22.7 +/- 3.5 mm2, and 10.8 +/- 2.7 mm2, respectively. While statistically significant differences could not be demonstrated between the magnitudes of the areas, a consistent difference in shape was noted between the proximal and middle levels, the tendon being flatter as it progressed over the humeral head and more triangular as it passed through the bicipital groove. We then performed cyclic relaxation tests and uniaxial tensile testing of the tendons which revealed a cyclic stress relaxation of 18 +/- 4% over ten cycles. All tensile failures occurred within the mid-portion of the tendon substance. Additionally, the modulus was calculated between 3% and 6% strain and found to be 421 +/- 212 MPa, while the ultimate tensile strength, ultimate strain, and strain energy density were 32.5 +/- 5.3 MPa, 10.1 +/- 2.7 %, and 1.9 +/- 0.4 MPa, respectively. These mechanical properties of the long head of the biceps tendon are of the same order of magnitude as tendons from other joints. The high stiffness of this tendon indicates that it has an ability to support the large load transferred to it by the muscle and to act as a humeral head depressor. [ABSTRACT FROM AUTHOR]

The Bankart lesion of the shoulder has long been associated with anterior instability. Our laboratory has developed a biomechanical model of the human shoulder which was used to determine the effects of creating a Bankart lesion on cadaveric specimens and then to compare the effects of two repair techniques. The model simulates the abducted, externally rotated position of the glenohumeral joint and uses pneumatic cylinders to simulate the rotator cuff forces. Specimens were tested intact following a partial Bankart lesion, following a complete Bankart lesion, and after performing a Bankart repair using three Mitek suture anchors. Finally, both the traditional and Mitek repairs were tested until failure. Strain in the inferior glenohumeral ligament (IGHL) and torque resistance was measured as an indication of instability of the joint. Strain was noted to decrease with increasing depth of lesion of the IGHL. Torsional rigidity of the shoulder decreased with increasing depth of lesion as well. Repairing the shoulder restores the strain and rigidity to control conditions. The mean load until failure was greater with the traditional repair than with the suture anchor technique. This study quantitates the effects of a Bankart lesion of the shoulder, and demonstrates that repairing the lesion with a suture anchor technique restores the biomechanics of the shoulder. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the effect of applied load on the magnitude, direction, and point of tibial intersection of the in situ forces of the anteromedial (AM) and posterolateral (PL) bands of the human anterior cruciate ligament (ACL) at 30 degrees and 90 degrees of knee flexion. An Instron was used to apply a 100 N anterior shear force to 11 human cadaver knees, 6 at 30 degrees of knee flexion and 5 at 90 degrees of knee flexion. A Universal Force Sensor (UFS) recorded the resultant 6 degree-of freedom (DOF) forces/moments. Each specimen then underwent serial removal of the AM and PL bands. With the knee limited to 1 DOF (anteroposterior), tests were performed before and after each structure was removed. Because the path was identical in each test, the principle of superposition was applied. Thus, the difference between the resultant forces could be attributed to the force carried by the structure just removed. The magnitudes of force in the ACL at 30 degrees and 90 degrees of knee flexion were 114.1 +/- 7.4 N and 90.8 +/- 8.3 N, respectively (P < 0.05). At 30 degrees, the AM and PL bundles carried 95% and 4% of the total ACL force, respectively. At 90 degrees, the AM and PL bands carried 85% and 13%, respectively (P < 0.05). The direction of the in situ force in the whole ACL as well as its two bands correlated with the anatomic orientation of the ligament.(ABSTRACT TRUNCATED AT 250 WORDS) [ABSTRACT FROM AUTHOR]

Approximately 44% of patients develop osteoarthritis (OA) following rupture of the anterior cruciate ligament (ACL) if the injury is left unrepaired. Restoring knee stability through reconstruction, while providing symptomatic relief, has not been shown to reduce the incidence of degenerative changes. In fact, recent studies have shown that 50%-60% of ACL-reconstructed patients go on to develop degenerative changes or frank osteoarthritis. In light of these data, our group suggests that the cause of post-traumatic osteoarthritis is not biomechanical but biochemical. To test this hypothesis, we measured levels of nine cytokines which are important in modulating physiological and pathophysiological metabolism of cartilage in knee joint synovial fluid following ACL rupture. Our patient population contained both acute and chronic ACL ruptures. A total of 84 samples were collected and analyzed by enzyme-linked immunosorbent assay. On the basis of the data collected, we were able to identify subgroups of patients who, on the basis of their synovial fluid cytokine profile, may be at greater or lesser risk of developing post-traumatic OA. In general, patients displayed concentrations of interleukin-1 alpha (IL-1 alpha), basic fibroblastic growth factor (bFGF), transforming growth factor-beta (TGF-beta), granulocyte/macrophage-colony stimulating factor (GM-CSF), IL-6, and IL-8 that we interpreted as being consistent with an inflammatory reaction. Of great interest is the fact that the levels of these cytokines were very similar in patients 4 weeks after injury and in chronic patients, leading us to hypothesize that a chronic smoldering inflammatory reaction persists after resolution of the acute effusion.(ABSTRACT TRUNCATED AT 250 WORDS) [ABSTRACT FROM AUTHOR]

Background and Purpose The homeostatic control of arterial BP is well understood with changes in BP resulting from changes in cardiac output ( CO) and/or total peripheral resistance ( TPR). A mechanism-based and quantitative analysis of drug effects on this interrelationship could provide a basis for the prediction of drug effects on BP. Hence, we aimed to develop a mechanism-based pharmacokinetic-pharmacodynamic (PKPD) model in rats that could be used to characterize the effects of cardiovascular drugs with different mechanisms of action ( MoA) on the interrelationship between BP, CO and TPR. Experimental Approach The cardiovascular effects of six drugs with diverse MoA, (amlodipine, fasudil, enalapril, propranolol, hydrochlorothiazide and prazosin) were characterized in spontaneously hypertensive rats. The rats were chronically instrumented with ascending aortic flow probes and/or aortic catheters/radiotransmitters for continuous recording of CO and/or BP. Data were analysed in conjunction with independent information on the time course of drug concentration using a mechanism-based PKPD modelling approach. Key Results By simultaneous analysis of the effects of six different compounds, the dynamics of the interrelationship between BP, CO and TPR were quantified. System-specific parameters could be distinguished from drug-specific parameters indicating that the model developed is drug-independent. Conclusions and Implications A system-specific model characterizing the interrelationship between BP, CO and TPR was obtained, which can be used to quantify and predict the cardiovascular effects of a drug and to elucidate the MoA for novel compounds. Ultimately, the proposed PKPD model could be used to predict the effects of a particular drug on BP in humans based on preclinical data. [ABSTRACT FROM AUTHOR]