Postural proteinuria associated with left renal vein entrapment: a follow-up evaluation

Imaging studies show entrapment of the left renal vein in the fork between the aorta and proximal superior mesenteric artery in most cases of isolated postural proteinuria. Therefore, it has been postulated that partial obstruction to the flow in the left renal vein in the upright position is a cause of this form of proteinuria. In a girl with isolated postural proteinuria, kidney ultrasonic imaging and Doppler flow scanning showed left renal vein entrapment. Seven years later, a new evaluation showed resolution of both postural proteinuria and left renal vein entrapment. The longitudinal observation provides substantial additional support for entrapment of the left renal vein by the aorta and superior mesenteric artery as a cause of isolated postural proteinuria.

Mechanical non-surgical treatment of peri-implantitis: a single-blinded randomized longitudinal clinical study. II. Microbiological results

BACKGROUND: Peri-implantitis is common in patients with dental implants. We performed a single-blinded longitudinal randomized study to assess the effects of mechanical debridement on the peri-implant microbiota in peri-implantitis lesions. MATERIALS AND METHODS: An expanded checkerboard DNA-DNA hybridization assay encompassing 79 different microorganisms was used to study bacterial counts before and during 6 months following mechanical treatment of peri-implantitis in 17 cases treated with curettes and 14 cases treated with an ultrasonic device. Statistics included non-parametric tests and GLM multivariate analysis with p<0001 indicating significance and 80% power. RESULTS: At selected implant test sites, the most prevalent bacteria were: Fusobacterium nucleatum sp., Staphylococci sp., Aggregatibacter actinomycetemcomitans, Helicobacter pylori, and Tannerella forsythia. 30 min. after treatment with curettes, A. actinomycetemcomitans (serotype a), Lactobacillus acidophilus, Streptococcus anginosus, and Veillonella parvula were found at lower counts (p<0.001). No such differences were found for implants treated with the ultrasonic device. Inconsistent changes occurred following the first week. No microbiological differences between baseline and 6-month samples were found for any species or between treatment study methods in peri-implantitis. CONCLUSIONS: Both methods failed to eliminate or reduce bacterial counts in peri-implantitis. No group differences were found in the ability to reduce the microbiota in peri-implantitis.

Apical surgery of a maxillary molar creating a maxillary sinus window using ultrasonics: a clinical case

AIM: To describe a method of carrying out apical surgery of a maxillary molar using ultrasonics to create a lateral sinus window into the maxillary sinus and an endoscope to enhance visibility during surgery. SUMMARY: A 37-year-old female patient presented with tenderness to percussion of the maxillary second right molar. Root canal treatment had been undertaken, and the tooth restored with a metal-ceramic crown. Radiological examination revealed an apical radiolucency in close proximity to the maxillary sinus. Apical surgery of the molar was performed through the maxillary sinus, using ultrasonics for the osteotomy, creating a window in the lateral wall of the maxillary sinus. During surgery, the lining of the sinus was exposed and elevated without perforation. The root-end was resected using a round tungsten carbide drill, and the root-end cavity was prepared with ultrasonic retrotips. Root-end filling was accomplished with MTA(®) . An endoscope was used to examine the cut root face, the prepared cavity and the root-end filling. No intraoperative or postoperative complications were observed. At the 12-month follow-up, the tooth had no clinical signs or symptoms, and the radiograph demonstrated progressing resolution of the radiolucency. KEY LEARNING POINTS: When conventional root canal retreatment cannot be performed or has failed, apical surgery may be considered, even in maxillary molars with roots in close proximity to the maxillary sinus. Ultrasonic sinus window preparation allows more control and can minimize perforation of the sinus membrane when compared with conventional rotary drilling techniques. The endoscope enhances visibility during endodontic surgery, thus improving the quality of the case.

Normative data for lung function and exhaled nitric oxide in unsedated healthy infants

Despite association with lung growth and long-term respiratory morbidity, there is a lack of normative lung function data for unsedated infants conforming to latest European Respiratory Society/American Thoracic Society standards. Lung function was measured using an ultrasonic flow meter in 342 unsedated, healthy, term-born infants at a mean ± sd age of 5.1 ± 0.8 weeks during natural sleep according to the latest standards. Tidal breathing flow-volume loops (TBFVL) and exhaled nitric oxide (eNO) measurements were obtained from 100 regular breaths. We aimed for three acceptable measurements for multiple-breath washout and 5-10 acceptable interruption resistance (R(int)) measurements. Acceptable measurements were obtained in ≤ 285 infants with high variability. Mean values were 7.48 mL·kg⁻¹ (95% limits of agreement 4.95-10.0 mL·kg⁻¹) for tidal volume, 14.3 ppb (2.6-26.1 ppb) for eNO, 23.9 mL·kg⁻¹ (16.0-31.8 mL·kg⁻¹) for functional residual capacity, 6.75 (5.63-7.87) for lung clearance index and 3.78 kPa·s·L⁻¹ (1.14-6.42 kPa·s·L⁻¹) for R(int). In males, TBFVL outcomes were associated with anthropometric parameters and in females, with maternal smoking during pregnancy, maternal asthma and Caesarean section. This large normative data set in unsedated infants offers reference values for future research and particularly for studies where sedation may put infants at risk. Furthermore, it highlights the impact of maternal and environmental risk factors on neonatal lung function.

Rapid Facilitation of Ultrasound Production and Lordosis in Female Hamsters by Horizontal Cuts Between the Septum and Preoptic Area

Horizontal cuts between the septum and preoptic area (anterior roof deafferentation, or ARD) dramatically affect sexual behavior, and in ways that could explain a variety of differences across behavioral categories (precopulatory, copulatory), species, and the sexes. Yet little is known about how these effects develop. Such information would be useful generally and could be pivotal in clarifying the mechanism for ultrasonic vocalization in female hamsters. Ultrasounds serve these animals as precopulatory signals that can attract males and help initiate mating. Their rates can be increased by either ARD or lesions of the ventromedial hypothalamus (VMN). If these effects are independent, they would require a mechanism that includes multiple structures and pathways within the forebrain and hypothalamus. However, it currently is not clear if they are independent: VMN lesions could affect vocalization by causing incidental damage to the same fibers targeted by ARD. Fortunately, past studies of VMN lesions have described a response with a very distinctive time course. This raises the possibility of assessing the independence of the two lesion effects by describing just the development of the response to ARD. To accomplish this, female hamsters were observed for levels of ultrasound production and lordosis before and after control surgery or ARD. As expected, both behaviors were facilitated by these cuts. Further, these effects began to appear by two days after surgery and were fully developed by six days. These results extend previous descriptions of the ARD effect by describing its development and time course. In turn, the rapid responses to ARD suggest that these cuts trigger disinhibitory changes in pathways that differ from those affected by VMN lesions. 2013

Tidal volume single breath washout of two tracer gases--a practical and promising lung function test

Background Small airway disease frequently occurs in chronic lung diseases and may cause ventilation inhomogeneity (VI), which can be assessed by washout tests of inert tracer gas. Using two tracer gases with unequal molar mass (MM) and diffusivity increases specificity for VI in different lung zones. Currently washout tests are underutilised due to the time and effort required for measurements. The aim of this study was to develop and validate a simple technique for a new tidal single breath washout test (SBW) of sulfur hexafluoride (SF6) and helium (He) using an ultrasonic flowmeter (USFM). Methods The tracer gas mixture contained 5% SF6 and 26.3% He, had similar total MM as air, and was applied for a single tidal breath in 13 healthy adults. The USFM measured MM, which was then plotted against expired volume. USFM and mass spectrometer signals were compared in six subjects performing three SBW. Repeatability and reproducibility of SBW, i.e., area under the MM curve (AUC), were determined in seven subjects performing three SBW 24 hours apart. Results USFM reliably measured MM during all SBW tests (n = 60). MM from USFM reflected SF6 and He washout patterns measured by mass spectrometer. USFM signals were highly associated with mass spectrometer signals, e.g., for MM, linear regression r-squared was 0.98. Intra-subject coefficient of variation of AUC was 6.8%, and coefficient of repeatability was 11.8%. Conclusion The USFM accurately measured relative changes in SF6 and He washout. SBW tests were repeatable and reproducible in healthy adults. We have developed a fast, reliable, and straightforward USFM based SBW method, which provides valid information on SF6 and He washout patterns during tidal breathing.

Effects Of The Flash Welding Process On Mechanical And Microstructural Properties Of Structural Steel Joints Assessed Using Dest

ASTM A529 carbon¿manganese steel angle specimens were joined by flash butt welding and the effects of varying process parameter settings on the resulting welds were investigated. The weld metal and heat affected zones were examined and tested using tensile testing, ultrasonic scanning, Rockwell hardness testing, optical microscopy, and scanning electron microscopy with energy dispersive spectroscopy in order to quantify the effect of process variables on weld quality. Statistical analysis of experimental tensile and ultrasonic scanning data highlighted the sensitivity of weld strength and the presence of weld zone inclusions and interfacial defects to the process factors of upset current, flashing time duration, and upset dimension. Subsequent microstructural analysis revealed various phases within the weld and heat affected zone, including acicular ferrite, Widmanstätten or side-plate ferrite, and grain boundary ferrite. Inspection of the fracture surfaces of multiple tensile specimens, with scanning electron microscopy, displayed evidence of brittle cleavage fracture within the weld zone for certain factor combinations. Test results also indicated that hardness was increased in the weld zone for all specimens, which can be attributed to the extensive deformation of the upset operation. The significance of weld process factor levels on microstructure, fracture characteristics, and weld zone strength was analyzed. The relationships between significant flash welding process variables and weld quality metrics as applied to ASTM A529-Grade 50 steel angle were formalized in empirical process models.

A new double-tracer gas single-breath washout to assess early cystic fibrosis lung disease

In cystic fibrosis (CF), tests for ventilation inhomogeneity are sensitive but not established for clinical routine. We assessed feasibility of a new double-tracer gas single-breath washout (SBW) in school-aged children with CF and control subjects, and compared SBW between groups and with multiple-breath nitrogen washout (MBNW). Three SBW and MBNW were performed in 118 children (66 with CF) using a side-stream ultrasonic flowmeter setup. The double-tracer gas containing 5% sulfur hexafluoride and 26.3% helium was applied during one tidal breath. Outcomes were SBW phase III slope (SIII(DTG)), MBNW-derived lung clearance index (LCI), and indices of acinar (S(acin)) and conductive (S(cond)) ventilation inhomogeneity. SBW took significantly less time to perform than MBNW. SBW and MBNW were feasible in 109 (92.4%) and 98 (83.0%) children, respectively. SIII(DTG) differed between children with CF and controls, mean±sd was -456.7±492.8 and -88.4±129.1 mg·mol·L(-1), respectively. Abnormal SIII(DTG) was present in 36 (59%) children with CF. SIII(DTG) was associated with LCI (r= -0.58) and S(acin) (r= -0.58), but not with S(cond). In CF, steeply sloping SIII(DTG) potentially reflects ventilation inhomogeneity near the acinus entrance. This tidal SBW is a promising test to assess ventilation inhomogeneity in an easy and fast way.

Endobronchial donor pre-treatment with ventavis: is a second administration during reperfusion beneficial to optimize post-ischemic function of non-heart beating donor lungs?

BACKGROUND: Lung retrieval from non-heart-beating donors (NHBD) has been introduced into clinical practice successfully. However, because of potentially deleterious effects of warm ischemia on microvascular integrity, use of NHBD lungs is limited by short tolerable time periods before preservation. Recently, improvement of NHBD graft function was demonstrated by donor pre-treatment using aerosolized Ventavis (Schering Inc., Berlin, Germany). Currently, there is no information whether additional application of this approach in reperfusion can further optimize immediate graft function. MATERIAL AND METHODS: Asystolic pigs (n = 5/group) were ventilated for 180-min of warm ischemia (groups 1-3). In groups 2 and 3, 100 microg Ventavis were aerosolized over 30-min using an ultrasonic nebulizer (Optineb). Lungs were then retrogradely preserved with Perfadex and stored for 3-h. After left lung transplantation and contralateral lung exclusion, grafts were reperfused for 6-h. Only in group 3, another dose of 100 microg Ventavis was aerosolized during the first 30-min of reperfusion. Hemodynamics, pO2/FiO2 and dynamic compliance were monitored continuously and compared to controls. Intraalveolar edema was quantified stereologically, and extravascular-lung-water-index (EVLWI) was measured. Statistics comprised ANOVA analysis with repeated measurements. RESULTS: Dynamic compliance was significantly lower in both Ventavis groups, but additional administration did not result in further improvement. Oxygenation, pulmonary hemodynamics, EVLWI and intraalveolar edema formation were comparable between groups. CONCLUSIONS: Alveolar deposition of Ventavis in NHBD lungs before preservation significantly improves dynamic lung compliance and represents an important strategy for improvement of preservation quality and expansion of warm ischemic intervals. However, additional application of this method in early reperfusion is of no benefit.

Decreasing gut wall glucose as an early marker of impaired intestinal perfusion

OBJECTIVE: The aim of this study was to assess the microcirculatory and metabolic consequences of reduced mesenteric blood flow. DESIGN: Prospective, controlled animal study. SETTING: The surgical research unit of a university hospital. SUBJECTS: A total of 13 anesthetized and mechanically ventilated pigs. INTERVENTIONS: Pigs were subjected to stepwise mesenteric blood flow reduction (15% in each step, n = 8) or served as controls (n = 5). Superior mesenteric arterial blood flow was measured with ultrasonic transit time flowmetry, and mucosal and muscularis microcirculatory perfusion in the small bowel were each measured with three laser Doppler flow probes. Small-bowel intramucosal Pco2 was measured by tonometry, and glucose, lactate (L), and pyruvate (P) were measured by microdialysis. MEASUREMENTS AND MAIN RESULTS: In control animals, superior mesenteric arterial blood flow, mucosal microcirculatory blood flow, intramucosal Pco2, and the lactate/pyruvate ratio remained unchanged. In both groups, mucosal blood flow was better preserved than muscularis blood flow. During stepwise mesenteric blood flow reduction, heterogeneous microcirculatory blood flow remained a prominent feature (coefficient of variation, approximately 45%). A 30% flow reduction from baseline was associated with a decrease in microdialysis glucose concentration from 2.37 (2.10-2.70) mmol/L to 0.57 (0.22-1.60) mmol/L (p < .05). After 75% flow reduction, the microdialysis lactate/pyruvate ratio increased from 8.6 (8.0-14.1) to 27.6 (15.5-37.4, p < .05), and arterial-intramucosal Pco2 gradients increased from 1.3 (0.4-3.5) kPa to 10.8 (8.0-16.0) kPa (p < .05). CONCLUSIONS: Blood flow redistribution and heterogeneous microcirculatory perfusion can explain apparently maintained regional oxidative metabolism during mesenteric hypoperfusion, despite local signs of anaerobic metabolism. Early decreasing glucose concentrations suggest that substrate supply may become crucial before oxygen consumption decreases.

Deadspace estimation from CO2 versus molar mass measurements in infants

BACKGROUND: Estimation of respiratory deadspace is often based on the CO2 expirogram, however presence of the CO2 sensor increases equipment deadspace, which in turn influences breathing pattern and calculation of lung volume. In addition, it is necessary to correct for the delay between the sensor and flow signals. We propose a new method for estimation of effective deadspace using the molar mass (MM) signal from an ultrasonic flowmeter device, which does not require delay correction. We hypothesize that this estimation is correlated with that calculated from the CO2 signal using the Fowler method. METHODS: Breath-by-breath CO2, MM and flow measurements were made in a group of 77 term-born healthy infants. Fowler deadspace (Vd,Fowler) was calculated after correcting for the flow-dependent delay in the CO2 signal. Deadspace estimated from the MM signal (Vd,MM) was defined as the volume passing through the flowhead between start of expiration and the 10% rise point in MM. RESULTS: Correlation (r = 0.456, P < 0.0001) was found between Vd,MM and Vd,Fowler averaged over all measurements, with a mean difference of -1.4% (95% CI -4.1 to 1.3%). Vd,MM ranged from 6.6 to 11.4 ml between subjects, while Vd,Fowler ranged from 5.9 to 12.0 ml. Mean intra-measurement CV over 5-10 breaths was 7.8 +/- 5.6% for Vd,MM and 7.8 +/- 3.7% for Vd,Fowler. Mean intra-subject CV was 6.0 +/- 4.5% for Vd,MM and 8.3 +/- 5.9% for Vd,Fowler. Correcting for the CO2 signal delay resulted in a 12% difference (P = 0.022) in Vd,Fowler. Vd,MM could be obtained more frequently than Vd,Fowler in infants with CLD, with a high variability. CONCLUSIONS: Use of the MM signal provides a feasible estimate of Fowler deadspace without introducing additional equipment deadspace. The simple calculation without need for delay correction makes individual adjustment for deadspace in FRC measurements possible. This is especially important given the relative large range of deadspace seen in this homogeneous group of infants.

Influence of beveling and ultrasound application on marginal adaptation of box-only Class II (slot) resin composite restorations

A laboratory study was performed to assess the influence of beveling the margins of cavities and the effects on marginal adaptation of the application of ultrasound during setting and initial light curing. After minimal access cavities had been prepared with an 80 microm diamond bur, 80 box-only Class II cavities were prepared mesially and distally in 40 extracted human molars using four different oscillating diamond coated instruments: (A) a U-shaped PCS insert as the non-beveled control (EMS), (B) Bevelshape (Intensiv), (C) SonicSys (KaVo) and (D) SuperPrep (KaVo). In groups B-D, the time taken for additional bevel finishing was measured. The cavities were filled with a hybrid composite material in three increments. Ultrasound was also applied to one cavity per tooth before and during initial light curing (10 seconds). The specimens were subjected to thermomechanical stress in a computer-controlled masticator device. Marginal quality was assessed by scanning electron microscopy and the results were compared statistically. The additional time required for finishing was B > D > C (p < or = 0.05). In all groups, thermomechanical loading resulted in a decrease in marginal quality. Beveling resulted in higher values for "continuous" margins compared with that of the unbeveled controls. The latter showed better marginal quality at the axial walls when ultrasound was used. Beveling seems essential for good marginal adaptation but requires more preparation time. The use of ultrasonic vibrations may improve the marginal quality of unbeveled fillings and warrants further investigation.

Vasopressin in septic shock: effects on pancreatic, renal, and hepatic blood flow

INTRODUCTION: Vasopressin has been shown to increase blood pressure in catecholamine-resistant septic shock. The aim of this study was to measure the effects of low-dose vasopressin on regional (hepato-splanchnic and renal) and microcirculatory (liver, pancreas, and kidney) blood flow in septic shock. METHODS: Thirty-two pigs were anesthetized, mechanically ventilated, and randomly assigned to one of four groups (n = 8 in each). Group S (sepsis) and group SV (sepsis/vasopressin) were exposed to fecal peritonitis. Group C and group V were non-septic controls. After 240 minutes, both septic groups were resuscitated with intravenous fluids. After 300 minutes, groups V and SV received intravenous vasopressin 0.06 IU/kg per hour. Regional blood flow was measured in the hepatic and renal arteries, the portal vein, and the celiac trunk by means of ultrasonic transit time flowmetry. Microcirculatory blood flow was measured in the liver, kidney, and pancreas by means of laser Doppler flowmetry. RESULTS: In septic shock, vasopressin markedly decreased blood flow in the portal vein, by 58% after 1 hour and by 45% after 3 hours (p < 0.01), whereas flow remained virtually unchanged in the hepatic artery and increased in the celiac trunk. Microcirculatory blood flow decreased in the pancreas by 45% (p < 0.01) and in the kidney by 16% (p < 0.01) but remained unchanged in the liver. CONCLUSION: Vasopressin caused marked redistribution of splanchnic regional and microcirculatory blood flow, including a significant decrease in portal, pancreatic, and renal blood flows, whereas hepatic artery flow remained virtually unchanged. This study also showed that increased urine output does not necessarily reflect increased renal blood flow.

Methodical study of nitrous oxide eddy covariance measurements using quantum cascade laser spectrometery over a Swiss forest

Nitrous oxide fluxes were measured at the Lägeren CarboEurope IP flux site over the multi-species mixed forest dominated by European beech and Norway spruce. Measurements were carried out during a four-week period in October–November 2005 during leaf senescence. Fluxes were measured with a standard ultrasonic anemometer in combination with a quantum cascade laser absorption spectrometer that measured N2O, CO2, and H2O mixing ratios simultaneously at 5 Hz time resolution. To distinguish insignificant fluxes from significant ones it is proposed to use a new approach based on the significance of the correlation coefficient between vertical wind speed and mixing ratio fluctuations. This procedure eliminated roughly 56% of our half-hourly fluxes. Based on the remaining, quality checked N2O fluxes we quantified the mean efflux at 0.8±0.4 μmol m−2 h−1 (mean ± standard error). Most of the contribution to the N2O flux occurred during a 6.5-h period starting 4.5 h before each precipitation event. No relation with precipitation amount could be found. Visibility data representing fog density and duration at the site indicate that wetting of the canopy may have as strong an effect on N2O effluxes as does below-ground microbial activity. It is speculated that above-ground N2O production from the senescing leaves at high moisture (fog, drizzle, onset of precipitation event) may be responsible for part of the measured flux.

Left renal vein entrapment: a frequent feature in children with postural proteinuria

In most Asian subjects with postural proteinuria, ultrasonic imaging and Doppler flow scanning disclose entrapment of the left renal vein in the fork between the aorta and the superior mesenteric artery. Little information is available on the possible occurrence of left venal rein entrapment in European subjects with postural proteinuria. Renal ultrasound with Doppler flow imaging was therefore performed on 24 Italian or Swiss patients with postural proteinuria (14 girls and ten boys, aged between 5.2 years and 16 years). Signs of aorto-mesenteric left renal vein entrapment were noted in 18 of the 24 subjects. In conclusion, aorto-mesenteric left renal vein entrapment is common also among European subjects with postural proteinuria.