Axial Area Research Articles

Epiglottis cross‐sectional area diminishes with increased severity of obstructive sleep apnea (LB70)

Obstructive sleep apnea (OSA) is a condition characterized by episodic upper airway collapse with continued diaphragmatic efforts during sleep. Significant cardiovascular and neurophysiological defects may result from brain injury accompanying repeated epochs of hypoxia. The majority of occlusions in OSA patients occur at the soft palate and uvula of the oropharynx. However, the extent of cross‐sectional area at the level of the epiglottis, between the oropharynx and hypopharynx, remains unclear. Morphological aspects at lower regions of the oropharynx, with different cranial nerve innervation from upper airway regions, may also contribute to obstruction. Using a 3.0 Tesla brain magnetic resonance imaging (MRI) scanner, we collected two high‐resolution T1‐weighted image series and measured axial cross‐sectional areas and oropharyngeal airway lengths for 13 mild or moderate OSA (mean age ± SD: 48.24 ± 8.28; AHI 5‐29.9 events/hr; 6 male), 11 severe OSA (48.81 ± 8.31; AHI 蠅 30 events/hr; 8 male) and 50 control subjects (47.17 ± 9.06; 28 male). Epiglottis cross‐sectional areas were significantly reduced in OSA over control subjects (p=0.005) and collapsible oropharyngeal airway lengths were significantly increased in OSA over control subjects (p <0.001). The diminished epiglottis cross‐sectional areas and increased airway lengths in OSA patients may contribute to a greater vulnerability for airway collapse.Supported by National Institutes of Health R01 HL‐113251.

Is echogenicity a viable metric for evaluating tendon properties in vivo?

Material properties of tissue in vivo present an opportunity for clinical analysis of healing progression and pathologies as well as provide an excellent research tool yielding quantified data for longitudinal and cross population studies. Echogenicity is a material׳s ability to reflect sound and, using ultrasound, it has been shown to increase with tendon tension in vitro, though this non-invasive measurement technique for determining mechanical properties has not been tested in vivo. The aim of this study was to establish if echogenicity, seen by the increase in image brightness, could be correlated to stress within a tissue. 18 Achilles tendons were imaged in the sagittal and transverse planes while producing a series of isometric contractions starting from rest and producing the torque equivalent of 0.5, 1.0, 1.5, and 2.0× body weights. Manual tracing identified the tendon in each of the images. The cross-sectional area determined from the transverse plane images in conjunction with the tendon force yielded the tendon stress. The echogenicity of the tendon was determined from the mean brightness change from rest to each of the contraction cases, measured from the sagittal plane images. A weak correlation existed between the echogenicity and stress (R=0.25) but it was found that there was no significant change in axial area during contraction (p=0.683) establishing the tendon as incompressible. Echogenicity proved to be non-functional for measuring the mechanical properties of the Achilles tendon due to the additional factors included with in vivo testing e.g. tendon twist and multi-axial loading.

Achnanthidium barbei sp. nov. and Achnanthidium costei sp. nov., two new diatom species from French rivers

Two new benthic freshwater species belonging to the genus Achnanthidium Kützing were found in French rivers located in the Languedoc-Roussillon region. Achnanthidium barbei and A. costei are described as new species based on light and scanning electron microscopy observations. These species belong to the ‘A. minutissimum complex’ based on the short, straight distal raphe fissures. Achnanthidium barbei and A. costei were found in rivers characterized by an alkaline pH and high phosphorus. Achnanthidium costei occurs in waters with very high conductivity and sulfate. The most characteristic morphological features of A. barbei are the bent frustule with recurved apices in girdle view, clearly lanceolate valves with convex margins and distinctly protracted apices, and the presence of up to six areolae per stria. Achnanthidium costei is characterized by a linear raphe valve outline and a wide axial area on the rapheless valve. Both species are compared with the most similar species: A. caravelense Novais & Ector, A. ennediense (Compère) Compère & Van de Vijver, A. eutrophilum (Lange-Bertalot) Lange-Bertalot, A. lineare W. Smith, A. minutissimun (Kützing) Czarnecki., A. pseudolineare Van de Vijver, Novais & Ector, A. sublineare Van de Vijver, Novais & Ector and A. tepidaricola Van de Vijver & M. de Haan. The ecological preferences of both species are assessed based on physicochemical analyses carried out on sites that are part of water quality monitoring networks.

Association of epicardial adipose tissue and left atrial size on non-contrast CT with atrial fibrillation: The Heinz Nixdorf Recall Study

Epicardial adipose tissue (EAT) is increased in subjects with atrial fibrillation (AF). Likewise, EAT is associated with left atrial (LA) size, as itself is a strong predictor of AF. We aimed to determine the association of EAT and LA size as computed tomography (CT)-derived measures with prevalent and incident AF and investigated whether both measures independently predict AF. Participants from the Heinz Nixdorf Recall study without known cardiovascular disease were included. At baseline, EAT, defined as fat volume inside the pericardial sac, and LA size, defined as an axial area at the level of the mitral valve, were quantified from non-contrast enhanced cardiac CT. AF was determined from electrocardiogram at baseline and also at 5-year follow-up examination. Overall, 3467 participants (age: 58.9 ± 7.6 years, 47% male) were included. Ninety-six subjects had AF (46 prevalent and 50 incident). A 1-standard deviation (SD) change of EAT was associated with nearly two-fold increased prevalence of AF in univariate analysis, which persisted after adjustment for AF risk factors [odds ratio (OR) (95% confidence interval, 95% CI): 1.38 (1.11-1.72), P = 0.003]. Ancillary adjusting for LA reduced the effect [1.26 (0.996-1.60), P = 0.054]. For incident AF, no relevant effect was observed for EAT when adjusting for risk factors [1.19 (0.88-1.61), P = 0.26]. In contrast, a 1-SD chance of LA was strongly associated with AF independently of EAT and risk factors [2.70 (2.22-2.20), P < 0.0001]. LA but not EAT as non-contrast CT-derived measures improved the prediction of AF over risk factors (receiver operating characteristics: 0.810-0.845, P = 0.025). LA size from non-contrast CT is strongly associated with prevalent and incident AF and ultimately diminishes the link of EAT with AF.

Effect of increased axial rotation angle on bone mineral density measurements of the lumbar spine

Background contextOsteoporosis frequently occurs in elderly people and is commonly associated with neuromuscular diseases or severe cerebral palsy. Osteoporosis can cause pain via compression fractures or secondary neurologic deficits; thus, accurate evaluation of bone mineral density (BMD) is essential for the prevention and treatment of osteoporosis. However, spinal axial rotation caused by scoliosis may affect the outcome of BMD tests, such that BMD measurements may be significantly greater than actual BMD in patients with severe scoliosis of the spine. PurposeWe investigated the effect of axial rotation angle on BMD measurements of the phantom spine. Study design/settingInvestigation for the effect of axial rotation with aluminum phantom spine. MethodsA GE-Lunar Aluminum Spine Phantom was used to assess BMD. Bone mineral content (BMC), BMD, and cross-sectional area were measured 100 times at L1–L4 using a GE Lunar Prodigy Vision system. Dual-energy X-ray absorptiometry was performed at axial rotation angles of 0° to 25° (5° intervals). ResultsCross-sectional area decreased and BMD values increased as the axial rotation angle increased, whereas BMC did not change significantly. A fitting function was obtained to evaluate the relationships among axial rotation angle, cross-sectional area, and BMD. We obtained an equation to estimate BMD at L1–L4: 1.000−0.001674x+0.0001043x2−0.000005333x3, where x denotes the axial rotation angle. We found that the observed BMD needed adjustment when the angle was more than 5°. ConclusionsBone mineral density values may be overestimated in patients with even slight (>5°) axial rotation. When osteoporosis is suspected in a clinical setting, the degree of axial rotation should be measured on a lumbar spine X-ray.

Reliability of upper airway linear, area, and volumetric measurements in cone-beam computed tomography

Our objective was to assess the intraexaminer and interexaminer reliabilities of upper airway linear, area, and volumetric measurements in cone-beam computed tomography. Cone-beam computed tomography scans of 12 subjects were randomly selected from a pool of 132 orthodontic patients. An undergraduate student, an orthodontist, and a dental radiologist independently made linear, area, and volumetric measurements. Linear anteroposterior and transversal measurements, cross-sectional area, sagittal area, minimum axial area, and volume measurements were made. The intraclass correlation coefficient (ICC) was used to assess intraexaminer and interexaminer reliabilities, and measurement errors were assessed. Agreement was further assessed with the Bland-Altman method and 95% limits of agreement. Overall, the ICC values indicated good reliability for the measurements assessed. The ICC values were greater than 0.9 (excellent) for 93% of intraexaminer and 73% of interexaminer assessments. Transversal width measurements and cross-sectional area at the level of the vallecula, however, had only moderate reliability (minimum ICC, 0.63), large 95% limits of agreement, and the greatest mean measurement errors (as high as 16% and 13% of the mean measurements, respectively). Linear anteroposterior measurements; cross-sectional areas at the levels of the palatal plane, soft palate, and tongue; and sagittal area and volume were reliable measurements, with a minimum ICC of 0.93 and more restricted limits of agreement. Based on these results, airway assessments by examiners with different backgrounds might have reliable anteroposterior linear measurements; cross-sectional areas at the levels of the palatal plane, soft palate, and tongue; and sagittal area and volume. The unreliable measurements were linear width, cross-sectional area at the level of the vallecula, and minimum axial area.

Stenopterobia cataractarum sp. nov. (Bacillariophyta), a new benthic diatom from a waterfall in Zambia, Africa

Rivers, streams and associated habitats have been sampled for diatoms in the relatively understudied Congo and Zambezi sister basins. The primary purpose of the sampling effort was to collect samples for biological monitoring purposes and the establishment of a diatom-based monitoring programme. However, a large number of possibly endemic and novel taxa have been encountered in this region making the application of diatom-based indices at a species level difficult. In this paper we describe a new species of Stenopterobia from the Ntumbachushi Falls in the Luapula Province of Zambia. This taxon is closely related to Stenopterobia delicatissima but chiefly differentiated by a lower number of striae, a well-defined unornamented lanceolate axial area and shortened ribs which do not fuse with the fenestrae. This taxon also shows some similarity to Stenopterobia delicatissima var. ghanaensis but the valves are consistently narrower.

Four-Dimensional Magnetic Resonance Imaging Using Axial Body Area as Respiratory Surrogate: Initial Patient Results

To evaluate the feasibility of a retrospective binning technique for 4-dimensional magnetic resonance imaging (4D-MRI) using body area (BA) as a respiratory surrogate. Seven patients with hepatocellular carcinoma (4 of 7) or liver metastases (3 of 7) were enrolled in an institutional review board-approved prospective study. All patients were simulated with both computed tomography (CT) and MRI to acquire 3-dimensional and 4D images for treatment planning. Multiple-slice multiple-phase cine-MR images were acquired in the axial plane for 4D-MRI reconstruction. Image acquisition time per slice was set to 10-15 seconds. Single-slice 2-dimensional cine-MR images were also acquired across the center of the tumor in orthogonal planes. Tumor motion trajectories from 4D-MRI, cine-MRI, and 4D-CT were analyzed in the superior-inferior (SI), anterior-posterior (AP), and medial-lateral (ML) directions, respectively. Their correlation coefficients (CC) and differences in tumor motion amplitude were determined. Tumor-to-liver contrast-to-noise ratio (CNR) was measured and compared between 4D-CT, 4D-MRI, and conventional T2-weighted fast spin echo MRI. The means (± standard deviations) of CC comparing 4D-MRI with cine-MRI were 0.97 ± 0.03, 0.97 ± 0.02, and 0.99 ± 0.04 in SI, AP, and ML directions, respectively. The mean differences were 0.61 ± 0.17 mm, 0.32 ± 0.17 mm, and 0.14 ± 0.06 mm in SI, AP, and ML directions, respectively. The means of CC comparing 4D-MRI and 4D-CT were 0.95 ± 0.02, 0.94 ± 0.02, and 0.96 ± 0.02 in SI, AP, and ML directions, respectively. The mean differences were 0.74 ± 0.02 mm, 0.33 ± 0.13 mm, and 0.18 ± 0.07 mm in SI, AP, and ML directions, respectively. The mean tumor-to-tissue CNRs were 2.94 ± 1.51, 19.44 ± 14.63, and 39.47 ± 20.81 in 4D-CT, 4D-MRI, and T2-weighted MRI, respectively. The preliminary evaluation of our 4D-MRI technique results in oncologic patients demonstrates its potential usefulness to accurately measure tumor respiratory motion with improved tumor CNR compared with 4D-CT.

A Comparative Evaluation of the Effect of Resin based Sealers on Retention of Crown Cemented with Three Types of Cement - An In Vitro Study.

In an effort to control postoperative sensitivity, dentin sealers are being applied following crown preparations, with little knowledge of how crown retention might be affected. A previous study demonstrated no adverse effect when using a gluteraldehyde-based sealer, and existing studies have shown conflicting results for resin-based products. This study determined the retention of the casting cemented with three types of cement, with and without use of resin sealers and it determined the mode of failure. Extracted human molars (n=60) were prepared with a flat occlusal, 20-degree taper, and 4-mm axial length. The axial surface area of each preparation was determined and specimens were distributed equally among groups (n=10). A single-bottle adhesive system (one step single bottle adhesive system) was used to seal dentin, following tooth preparation. Sealers were not used on the control specimens. The test castings were prepared by using Ni-Cr alloy for each specimen and they were cemented with a seating force of 20 Kg by using either Zinc Phosphate (Harvard Cement), Glass Ionomer (GC luting and lining cement,GC America Inc.) and modified-resin cement (RelyXTMLuting2). Specimens were thermocycled for one month and were then removed along the path of insertion by using a Universal Testing Machine at 0.5 mm/min. A single-factor ANOVA was used with a p value of .05. The nature of failure was recorded and the data was analyzed by using Chi-square test. Mean dislodgement stress for Zinc phosphate (Group A) was 24.55±1.0 KgF and that for zinc phosphate with sealer (Group D) was 14.65±0.8 KgF. For glass ionomer (Group B) without sealer, the mean value was 32.0±1.0 KgF and mean value for glass ionomer with sealer (Group E) was 37.90±1.0 KgF. The mean value for modified resin cement (Group C) was 44.3±1.0KgF and that for modified resins with sealer (Group F) was 57.2±1.2 KgF. The tooth failed before casting dislodgement in 8 to 10 specimens cemented with modified-resin cement. Resin sealer decreased casting retentive stress by 46% when it was used with Zinc phosphate. However, sealer use resulted in 60% increased retention when it was used with Glass ionomer cement. The modified-resin cement produced the highest mean dislodgement stress, which nearly always exceeded the strength of the tooth.

Physical Properties of Basmati Varieties of Paddy

Physical properties of two varieties (PB1 and PB1121) of basmati paddy were determined at moisture contents ranging between 22.5 and 9.5% (w.b.). Moisture content was found to have significant effect on the properties of both the varieties. Axial dimensions, sphericity and surface area of both varieties decreased with decrease in moisture content. The thousand grain mass, bulk density and angle of repose decreased from 27.83 to 19.72 g, 378 to 322 kg.m-3 and 48.54 to 30.06 degrees, respectively while true density and porosity increased from 1266 to 1298 kg.m-3 and 70.17 to 75.19%, respectively, with decrease in moisture content in PB1. In case of PB1121 variety, the corresponding values were 29.94 to 22.24 g, 464 to 429 kg.m-3, 36.06 to 28.06 degrees, 1366 to 1398 kg.m-3 and 60.03 to 69.31%, respectively. Terminal velocity and coefficient of friction decreased with decrease in moisture content, while hardness of paddy increased.

The morphotectonics and its evolutionary dynamics of the central Southwest Indian Ridge (49° to 51°E)

The morphotectonic features and their evolution of the central Southwest Indian Ridge (SWIR) are discussed on the base of the high-resolution full-coverage bathymetric data on the ridge between 49 degrees-51 degrees E. A comparative analysis of the topographic features of the axial and flank area indicates that the axial topography is alternated by the ridge and trough with en echelon pattern and evolved under a spatial-temporal migration especially in 49 degrees-50.17 degrees E. It is probably due to the undulation at the top of the mantle asthenosphere, which is propagating with the mantle flow. From 50.17 degrees to 50.7 degrees E, is a topographical high terrain with a crust much thicker than the global average of the oceanic crust thickness. Its origin should be independent of the spreading mechanism of ultra-slow spreading ridges. The large numbers of volcanoes in this area indicate robust magmatic activity and may be related to the Crozet hot spot according to RMBA (residual mantle Bouguer anomaly). The different geomorphological feature between the north and south flanks of the ridge indicates an asymmetric spreading, and leading to the development of the OCC (oceanic core complex). The tectonic activity of the south frank is stronger than the north and is favorable to develop the OCC. The first found active hydrothermal vent in the SWIR at 37 degrees 47'S, 49 degrees 39'E is thought to be associated with the detachment fault related to the OCC.

In vitro evaluation of the marginal and internal discrepancies of different esthetic restorations

ObjectiveThis study examined the fit of two types of all-ceramic single crowns and indirect composite resin full coverage crowns. Material and MethodsThirty intact human mandibular first premolars were selected for this study and prepared using a machine to standardize the dimensions and randomly divided into 3 groups. Slip cast (IC) (In-Ceram Zirconia, Vita Zahnfabrik), copy-milled zirconia (CM) (ICE, Zirkonzahn) and indirect composite resin crowns (NECO, HeraeusKulzer, Hanau, Germany), (N=30, 10 per group) were fabricated according to each manufacturer's recommendations. Before cementation, discrepancies were measured at the marginal zone in each crown. Crowns were then cemented with G-Cem capsule self-adhesive luting cement (GC Corporation, Tokyo, Japan). Four positions were marked for each zone (mid-facial, mid-mesial, mid-distal, and mid-lingual) and three measurements were made at each of the four positions yielding to a total of 12 measurements per crown before and after cementation. The measurements were performed at a different magnification using a stereo microscope (SZ11, Olympus, Japan). Marginal, axial and occlusal zone discrepancies (µm) were evaluated after cementation. The data were statistically analyzed using two-way ANOVA and Tukey's test. ResultsBefore cementation, significantly less marginal discrepancies were noted compared with after cementation in all groups (p<0.05). No significant differences were found within each zone (Marginal= IC: 84.2, NECO: 95.22, CM: 84.22; Axial= IC: 54.22, NECO: 64.2, CM: 55.22; Occlusal= IC: 119.97, NECO: 129.18, CM: 121.15) in the three crown systems (p>0.05). Occlusal zone discrepancies were significantly higher than those of the marginal and axial zones in all groups (p<0.05). ConclusionsSlip cast and copy-milled zirconia crowns showed comparable fit to composite resin crowns in all marginal, axial and occlusal areas.

Resin yield in Pinus pinaster is related to tree dendrometry, stand density and tapping-induced systemic changes in xylem anatomy

Pinus pinaster Ait. is the most widespread conifer in Spain and is now the only species tapped for its oleoresin. The role of tree size and xylem anatomy at distal parts (⩾10cm) aside from the tapping wound in the resin yield potential of this species was evaluated. Twenty-six tapped trees with contrasting resin yield classes and 12 non-tapped (control) trees, growing in two locations with the same climate conditions but different stand density and soil characteristics, were selected for the study. In tissues not affected by the tapping wound, the number of radial resin canals per mm2 and resin canal volume per growth ring unit are related to resin yield. The number of radial canals per mm2 and resin yield are strongly related to tree diameter and percentage of live crown. The area per mm2 of axial resin canals is related to high yielding trees, but only in the location with higher plant density and poorer soil quality. In tapped trees, an increase in axial canal frequency and area was found during the three years following the start of tapping activity, suggesting that canal formation is a systemic induced response to wounding. Tree diameter and percentage of live crown and radial resin canal frequency could be useful criteria for estimating resin yields in P. pinaster and could be applied to improve tapping management and breeding programs. The systemic defense system of trees should be taken into account to improve tapping techniques and resin yield.

Validation Study of the Accuracy of Echocardiographic Measurements of Systemic Blood Flow Volume in Newborn Infants

BackgroundThe echocardiographic assessment of circulatory function in sick newborn infants has the potential to improve patient care. However, measurements are prone to error and have not been sufficiently validated. Phase-contrast magnetic resonance imaging (MRI) provides highly validated measures of blood flow and has recently been applied to the newborn population. The aim of this study was to validate measures of left ventricular output and superior vena caval flow volume in newborn infants.MethodsEchocardiographic and MRI assessments were performed within 1 working day of each other in a cohort of newborn infants.ResultsExaminations were performed in 49 infants with a median corrected gestational age at scan of 34.43 weeks (range, 27.43–40 weeks) and a median weight at scan of 1,880 g (range, 660–3,760 g). Echocardiographic assessment of left ventricular output showed a strong correlation with MRI assessment (R2 = 0.83; mean bias, −9.6 mL/kg/min; limits of agreement, −79.6 to +60.0 mL/kg/min; repeatability index, 28.2%). Echocardiographic assessment of superior vena caval flow showed a poor correlation with MRI assessment (R2 = 0.22; mean bias, −13.7 mL/kg/min; limits of agreement, −89.1 to +61.7 mL/kg/min; repeatability index, 68.0%). Calculating superior vena caval flow volume from an axial area measurement and applying a 50% reduction to stroke distance to compensate for overestimation gave a slightly improved correlation with MRI (R2 = 0.29; mean bias, 2.6 mL/kg/min; limits of agreement, −53.4 to +58.6 mL/kg/min; repeatability index, 54.5%).ConclusionsEchocardiographic assessment of left ventricular output appears relatively robust in newborn infant. Echocardiographic assessment of superior vena caval flow is of limited accuracy in this population, casting doubt on the utility of the measurement for diagnostic decision making.

CT angiography in the detection of carotid body enlargement in patients with hypertension and heart failure

The carotid body (CB) has previously been found to be enlarged and hyperactive in various disease states such as heart failure (HF), hypertension (HTN), and respiratory disease. Evaluation of CB size in these disease states using imaging has not been performed. The purpose of this case-control study was to compare CB sizes in patients with HF and HTN with those of controls using CT angiography. A retrospective review was performed on 323 consecutive patients who had neck computed tomography angiography (CTA) exams in 2011. Following extensive review, 17 HF and HTN patients and 14 controls were identified. Two radiologists blinded to the patient disease status made consensus bilateral carotid body (CB) measurements on the CTA exams using a previously described standardized protocol. CB axial cross-sectional areas were compared between HF and HTN cases and controls using a paired t test. The right CB demonstrated a mean cross-sectional area of 2.79 mm(2) in HF and HTN patients vs. 1.40 mm(2) in controls (p = 0.02). The left CB demonstrated a mean cross-sectional area of 3.13 mm(2) in HF and HTN patients vs. 1.53 mm in controls (p = 0.03). Our results provide imaging evidence that the carotid bodies are enlarged in patients with HF and HTN. Our case-control series suggests that this enlargement can be detected on neck CTA.

Abstract 285: Renal Inflammation and Injury Markers Correlate Directly With Cortical and Fractional Hypoxia Measured With Blood Oxygen Level Dependent (BOLD) MR in Human Atherosclerotic Renal Artery Stenosis

Background: Atherosclerotic renal artery stenosis (ARAS) reduces renal blood flow (RBF) and amplifies regional kidney hypoxia, but their relationship to tissue inflammation and injury markers is poorly understood. We tested the hypothesis that renal injury, reflected by renal vein levels of neutrophil gelatinase associated lipocalin (NGAL) and inflammatory cytokines monocyte chemoattractant protein-1 (MCP-1) would be magnified with severe occlusive vascular disease in humans with ARAS. Methods: Inpatient studies performed in patients with ARAS (n=40, 71.3±11% occlusion by CT angiography) or essential hypertension (EH) (n=30), during fixed Na+ intake and ACE/ARB Rx. Single-kidney cortical and medullary perfusion and RBF were measured using multidetector CT, and glomerular filtration rate (GFR) by iothalamate clearance. Tissue deoxyhemoglobin levels (R2*) and fractional kidney hypoxia (% of axial area with R2*&gt;30/s) were measured by BOLD-MRI at 3T. Results: Single kidney RBF, cortical and medullary perfusion were reduced in the post-stenotic kidney, as was GFR. Renal vein NGAL, MCP-1 and fractional hypoxia were higher in patients with ARAS than EH. NGAL and MCP-1 levels correlated directly with cortical R2* and fractional hypoxia (r = 0.52, P &lt;0 .0001 and r = 0.4, P = 0.0006) and with the degree of artey stenosis (r = 0.37, P = 0.04 and r = 0.35, P = 0.05). GFR correlated inversely with NGAL (r= - 0.5, P &lt;0.0001). Conclusions: Our results demonstrate that elevated renal venous markers of kidney inflammation (MCP-1) and injury (NGAL) in ARAS are correlated with the severity of tissue hypoxia as measured by BOLD MR, suggesting a possible link between kidney inflammation and hypoxia.

Achnanthidium palmeti (Bacillariophyta, Achnanthidiaceae), a new freshwater species from Réunion Island

Recent survey of the epilithic diatoms in the running waters of Réunion Island led to the discovery of a new species of Achnanthidium. Achnanthidium palmeti sp. nov. belongs to the group of Achnanthidium taxa with terminal raphe fissures curved to the same side of the valve. The new species differs from other taxa in this group by a higher stria density and the areolae morphology along the axial area; moreover, apart from Achnanthidium latecephalum H. Kobayasi, A. palmeti sp. nov. is the only species having raphe vestiges. The new species was found in oligotrophic waters with very low conductivity and circumneutral pH.

Stent Revascularization Restores Cortical Blood Flow and Reverses Tissue Hypoxia in Atherosclerotic Renal Artery Stenosis but Fails to Reverse Inflammatory Pathways or Glomerular Filtration Rate

Atherosclerotic renal artery stenosis (ARAS) is known to reduce renal blood flow, glomerular filtration rate (GFR) and amplify kidney hypoxia, but the relationships between these factors and tubulointerstitial injury in the poststenotic kidney are poorly understood. The purpose of this study was to examine the effect of renal revascularization in ARAS on renal tissue hypoxia and renal injury. Inpatient studies were performed in patients with ARAS (n=17; >60% occlusion) before and 3 months after stent revascularization, or in patients with essential hypertension (n=32), during fixed Na(+) intake and angiotensin converting enzyme/angiotensin receptors blockers Rx. Single kidney cortical, medullary perfusion, and renal blood flow were measured using multidetector computed tomography, and GFR by iothalamate clearance. Tissue deoxyhemoglobin levels (R(2)*) were measured by blood oxygen level-dependent MRI at 3T, as was fractional kidney hypoxia (percentage of axial area with R(2)*>30/s). In addition, we measured renal vein levels of neutrophil gelatinase-associated lipocalin, monocyte chemoattractant protein-1, and tumor necrosis factor-α. Pre-stent single kidney renal blood flow, perfusion, and GFR were reduced in the poststenotic kidney. Renal vein neutrophil gelatinase-associated lipocalin, tumor necrosis factor-α, monocyte chemoattractant protein-1, and fractional hypoxia were higher in untreated ARAS than in essential hypertension. After stent revascularization, fractional hypoxia fell (P<0.002) with increased cortical perfusion and blood flow, whereas GFR and neutrophil gelatinase-associated lipocalin, monocyte chemoattractant protein-1, and tumor necrosis factor-α remained unchanged. These data demonstrate that despite reversal of renal hypoxia and partial restoration of renal blood flow after revascularization, inflammatory cytokines and injury biomarkers remained elevated and GFR failed to recover in ARAS. Restoration of vessel patency alone failed to reverse tubulointerstitial damage and partly explains the limited clinical benefit of renal stenting. These results identify potential therapeutic targets for recovery of kidney function in renovascular disease.

Cavinula lilandae (Bacillariophyta), a new diatom species from the Congo Basin, Central Africa

Cavinula lilandae, a small new diatom from the Congo Basin in Central Africa, was observed in acid riverine habitats in an almost pristine tropical rain forest. It occurred in a periphytic diatom community dominated by Eunotia spp. and Fragilariforma strangulata (Zanon) Williams & Round. Beside the type locality in the Baomba Stream, and the closely located Lilanda River, in the Democratic Republic of Congo, this taxon was also observed in a small river in Zambia, north of the Bangweulu swamps. Cavinula lilandae is distinguished from other taxa within the genus Cavinula D.G. Mann & A.J. Stickle by the following characteristics: uniseriate striae becoming irregularly biseriate near the poles; irregularly formed areolae; and irregular depressions in the valve face close to the axial area which are not perforating the valve face.

Matched-pair analyses of resting and dynamic morphology between Monarc and TVT-O procedures by ultrasound

ObjectiveTo determine morphologic differences between Monarc and TVT-O procedures in axial and coronal planes by three- and four-dimensional (3D and 4D) ultrasound. Study designRetrospective chart audits and ultrasound analyses were conducted on 128 women who had undergone either Monarc or TVT-O procedures for urodynamic stress incontinence. Thirty matched pairs of the two successful procedures were randomly selected and compared. Matched variables were age, parity, body mass index, cesarean status, menopausal status, and primary surgeries. Six-month postoperative 3D and 4D ultrasound results obtained at rest, on straining, and during coughing in these 60 women were analyzed. Assessed ultrasound parameters included the axial tape urethral distance (aTUD), axial central urethral echolucent area (aUCEA), axial tape angle (aTA), and coronal tape angle (cTA), all of which were measured at three equidistant points along the tapes. Paired t-tests were used to compare differences in ultrasound parameters between women after the two procedures and a P value <0.004 was considered significant after Bonferroni correction. ResultsAt rest, women subjected to Monarc procedures had a significantly wider aTA at one-fourth of the tape and a wider cTA at one-, two-, and three-fourths of the tape than did those subjected to TVT-O procedures. There were no significant differences in other resting ultrasound parameters between these two procedures. Additionally, after both procedures women had comparable straining and coughing ultrasound manifestations as well as respective dynamic changes. ConclusionDespite flatter resting tape angulations in women following Monarc procedures, both Monarc and TVT-O tapes had equivalent dynamic patterns and changes assessed by 4D ultrasound.