Dunn's Method Research Articles

Effects of ocean acidification on growth and feeding rates of spotted jellyfish Phyllorhiza punctata early life stage/polyps.

Effects of ocean acidification on growth and feeding rates of spotted jellyfish Phyllorhiza punctata early life stage/polyps.

Asymmetric faradaic assembly of Bi2O3 and MnO2 for a high-performance hybrid electrochemical energy storage device.

In the current study, we have explored the coupling of Bi2O3 negative electrode and MnO2 positive electrode materials as an asymmetric faradaic assembly for a high-performance hybrid electrochemical energy storage device (HEESD). Aiming at a low-cost device, both the electrodes have been synthesized by a simple, scalable, and cost-effective chemical synthesis method. After their requisite structure-morphological confirmation and correlation, these electrodes were separately examined for their electrochemical performance in a three-electrode configuration. The results obtained confirm that Bi2O3 and MnO2 exhibit 910 C g−1 and 424 C g−1 specific capacity, respectively, at 2 A g−1 current density. Notably, the performance of both electrodes has been analyzed using Dunn's method to highlight the distinct nature of their faradaic properties. Afterwards, the asymmetric faradaic assembly of both electrodes, when assembled as a HEESD (MnO2//Bi2O3), delivered 411 C g−1 specific capacity at 1 A g−1 current density due to the inclusive contribution from the capacitive as well as the non-capacitive faradaic quotient. Consequently, the assembly offers an excellent energy density of 79 W h kg−1 at a power density of 702 W kg−1, with a magnificent retention of energy density up to 21.1 W h kg−1 at 14 339 W kg−1 power density. Moreover, it demonstrates long-term cycling stability at 10 A g−1, retaining 85.2% of its initial energy density after 5000 cycles, which is significant in comparison with the previously reported literature. Additionally, to check the performance of the device in real time, two HEESDs were connected in series to power a light-emitting diode. The results obtained provide significant insight into hybrid coupling, where two different faradaic electrodes can be combined in a synergistic combination for a high-performance HEESD.

Chronic nail biting, orthodontic treatment and Enterobacteriaceae in the oral cavity.

BackgroundChronic nail biting is common in children and young adults. Auto inoculation of environmental pathogens can manifest as infection in distant organs. Multi-drug resistance gram negative bacteria are on the rise globally. Several of the foodborne bacteria fall within the Enterobacteriaceae family but very few studies have explored these microbes in the oral cavity of children with chronic nail-biting habit or orthodontic treatment. The study aims to investigate oral load of Enterobacteriaceae in children with chronic nail-biting habit and or those undergoing orthodontic treatment.Material and Methods150 children (no nail-biting n=30, nail biting n=60, fixed orthodontic treatment n =30 and a combination of fixed orthodontic appliance use and nail-biting habit n =30) were assessed for culture based microbiological investigation. The concentrated oral rinse technique was used. The rinse was inoculated in MacConkey’s and Blood Agar. The gram stained culture was subjected to biochemical tests for sub-species identification using Biomerieux Vitek 2 Compact Automated Microbiological Analyzer. Fisher’s exact and Kruskal Wallis with post hoc analysis using Dunn method was performed to test association and difference between groups.ResultsEnterobacteriaceae was positive for 72% of the children. Of them, nail biting or orthodontic treatment group comprised 89%. Those with a combination of nail biting and undergoing orthodontic treatment exhibited highest CFU/ml and those without nail biting or orthodontic treatment exhibited the lowest. Three of the four organisms isolated tested positive in the orthodontic treatment group. E. coli was positive in 38% of the children while Klebsiella and E. cloacae were isolated exclusively in the orthodontic treatment group.ConclusionsChronic nail biting or the use of fixed orthodontic appliances is associated with higher incidence of Enterobacteriaceae in the oral cavity. Oral health professionals play an important role in preventing multi drug resistance infectious diseases. Key words:Enterobacteriaceae, nail-biting, Onychophagia, orthodontic treatment.

Improved recovery of human islets from young donor pancreases utilizing increased protease dose to collagenase for digesting peri-islet extracellular matrix.

Human islet isolation from young donor pancreases (YDP) utilizing the current purified standard dose of collagenase-protease enzyme mixtures often results in the release of a high percentage of mantled islets. Mantled islets are those surrounded by exocrine tissue and are difficult to purify by density gradient centrifugation, leading to poor islet recovery. Based on difference in extracellular matrix, and total collagen content between YDP and old donor pancreas (ODP, > 35 Y) led us to compare results from islet isolation using increased collagenase combination (ICC) or increased protease combination (IPC), to the standard enzyme combination (SEC) in a "trisected" pancreas model to overcome the donor-to-donor variability. These results showed a reduced percentage of mantled islets (17%±7.5%) and higher postpurification islet recovery (83.8%±5.6%) with IPC. Furthermore, these results were confirmed in 13 consecutive whole pancreas islet isolations utilizing IPC from VitaCyte, Roche, or SERVA collagenase-protease enzyme mixtures. Results obtained from in vitro and in vivo islet functional assessment indicated that islets isolated using IPC retained normal islet morphology, insulin secretion, and the ability to reverse diabetes after transplantation in diabetic nude mice. This is the first report utilizing trisected pancreas to assess the effectiveness of different enzyme combinations to improve islet recovery from young donor pancreases.

Ultra-thin occlusal veneers bonded to enamel and made of ceramic or hybrid materials exhibit load-bearing capacities not different from conventional restorations

ObjectivesThe objective of this study was to test whether or not the load-bearing capacity of occlusal veneers bonded to enamel and made of ceramic or hybrid materials does differ from those of porcelain-fused-to-metal or lithium disilicate glass ceramic crowns. Material and methodsIn 80 human molars occlusal enamel was removed without extending into the dentin in order to mimic substance defects caused by attrition. The restorations were digitally designed at a standardized thickness of either 0.5 mm or 1.0 mm. For each thickness, 4 test groups were formed each including a different restorative material: “0.5-ZIR”: 0.5 mm thick zirconia (Vita YZ HT); “1.0-ZIR”: 1.0 mm thick zirconia (Vita YZ HT); “0.5-LDC”: 0.5 mm thick lithium disilicate ceramic (IPS e.max Press); “1.0-LDC”: 1.0 mm thick lithium disilicate ceramic (IPS e.max Press); “0.5-HYC”: 0.5 mm thick PICN (Vita Enamic); “1.0-HYC”: 1.0 mm thick PICN (Vita Enamic); “0.5-COC”: 0.5 mm thick tooth shaded resin composite (Lava Ultimate) and “1.0-COC”: 1.0 mm thick tooth shaded resin composite (Lava ultimate). Each group consists of 10 specimens. Two additional groups of 10 specimens each were used as controls and exhibited conventional crown preparations. In one group the crowns were made of lithium-disilicate ceramic (“CLD”: IPS e.max CAD) and the other group consisted of porcelain-fused to metal crowns (“PFM”). All restorations were cemented onto the prepared teeth following the manufacturer's instruction of the corresponding luting cement. Subsequently, they were thermo-mechanically aged and then loaded until fracture. Load-bearing capacities (Fmax) between the groups were compared applying the Kruskal-Wallis test (p < 0.05) and pairwise group comparisons using the Dunn's method. ResultsMedian values (and quartiles) for the load-bearing capacity amounted to (Fmax) 2′407 (1′670; 2′490) N for the CLD group and to 2′033 (1′869; 2′445) N for the PFM group. For the 0.5 mm thick restorations Fmax reached the highest median value in group 0.5-HYC 2′390 (1′355; 2′490) N, followed by 0.5-COC 2′200 (1′217; 2′492) N and 0.5-LDC 1′692 (1′324; 2′355) N. No results were obtained for group 0.5-ZIR due to the impracticability to fabricate ultra-thin specimens. The distribution of the values for the 1.0 mm thick restorations was 2′489 (2′426; 2′491) N for 1.0-COC, 2′299 (2′156; 2′490) N for 1.0-ZIR, 2′124 (1′245; 2′491) N for 1.0-HYC, and 1′537 (1′245; 1′783) N for 1.0-LDC. The differences of the medians between the test and the control groups did not reach statistical significance for the 0.5 mm thick specimens (KW: p = 0.6952 and p = 0.6986). Within the groups exhibiting 1.0 mm thickness, however, significant different medians were found: 1.0-LDC < 1.0-ZIR and 1.0-LDC < 1.0-COC (KW: p < 0.0209). ConclusionsRegarding their maximum load-bearing capacity, minimally invasive occlusal veneers made of ceramic and hybrid materials can be applied to correct occlusal tooth wear and thus replace conventional crown restorations.

Efficacy of assisted balance training in chronic vestibular vertigo

Physicians are found to have a great and increasing amount of patients suffering of vertigo in their everyday practice. For the treatment of the balance disorders, a vestibular training was introduced which played an influential role based on our study. Our aim was to create an easy and comprehensible training program which can be performed even with a family member. Our clinical treatment consists of intravenous vasoactive medicine administration, combined with vestibular training. For the investigation of the improvement we used the Jacobson and Newman questionnaire, and ultrasound-computer-craniocorpography. The statistical evaluation was based on ANOVA, Kruskal-Wallis test and Dunn's post method (p<0.05). After the combined clinical treatment, the patients' average training results showed improvement. Following the eight-day training, the patients scored higher results from day to day due to the improvement of their abilities while doing the different tasks. Moreover, the questionnaire results also showed the improvement of their status. By improving the brain stem circulation, combined with an assisting training program, there is a significant decrease in the complaints and an overall improvement in the quality of life, even though the imbalance cannot be cured. Orv Hetil. 2018; 159(12): 470-477.

Association study of multiple antibiotic resistance and virulence: a strategy to assess the extent of risk posed by bacterial population in aquatic environment.

The present study explored the association between multiple antibiotic resistance (MAR) index and virulence index to determine what percent of environmental antibiotic-resistant (eARB) bacteria could pose threat as potential pathogen. 16srRNA-based sequencing of 113 non-duplicate isolates identified majority of them to be gram negative belonging to Enterobacter, Pseudomonas, Aeromonas, Proteus, Acinetobacter, and Klebsiella. Statistical comparison of MAR indices of the abovementioned genera indicated differences in the median values among the groups (p<0.001). Pair-wise multiple comparison by Dunn's method indicated significant difference in MAR indices (p<0.05), based on which multiple antibiotic resistance phenotype could be ranked in the order Pseudomonas>Klebsiella=Acinetobacter>Proteus>Aeromonas>Enterobacter. Association between MAR index and virulence index revealed that 25% of isolates in the population under study posed high threat to human/animal or both; out of which 75% isolates belonged to genus Pseudomonas. Based on observations of comparative analysis of the six gram-negative genera, it could be concluded that Pseudomonas isolates from environment pose significantly high threat as potential pathogens while Enterobacter isolates posed no threat.

Comparison of methods and formulas used in umbilical venous catheter placement.

Central venous access is frequently provided by way of umbilical venous catheter placement in critically ill newborns. This study compared the methods of Dunn, Shukla-Ferrara, and Revised Shukla-Ferrara in determining the appropriate insertion length of umbilical vein catheters. This prospective observational study was carried out in 121 newborns with umbilical venous catheter, group 1 (n=41) used Dunn method, group 2 (n=40) used the Shukla-Ferrara formula, and group 3 used revised Shukla-Ferrara formula (n=40). Catheter tip position was evaluated with an anterior-posterior chest radiograph after insertion of the umbilical venous catheter. The ideal position for the umbilical venous catheter was defined as the catheter tip being visible between the 9th and 10th thoracic vertebrae on an anterior-posterior chest radiograph. The position of the umbilical venous catheter was considered too high if the tip of the catheter was higher than the 9th thoracic vertebra and too low if the tip was below the 10th thoracic vertebra. The following data were collected: appropriate, inappropriate (low, high) placement, and complications of umbilical venous catheterization. In the Shukla-Ferrara group, 53% (17/32) of umbilical venous catheters were placed directly in the appropriate position, compared with 40% (12/30) in the revised Shukla-Ferrara group and 38% (11/29) in the Dunn method group. Umbilical venous catheter-related complications developed in two patients, thrombus in one, and catheter-related blood stream infection in the other. This study showed that the Shukla-Ferrara formula is more accurate in predicting the insertion length for umbilical venous catheters, though statistical significance was not found. Further studies with larger samples are needed on this topic.

Performance of nonparametric multiple comparison tests under heteroscedasticity, dependency, and skewed error distribution

ABSTRACTIn this article, an extensive Monte Carlo simulation study is conducted to evaluate and compare nonparametric multiple comparison tests under violations of classical analysis of variance assumptions. Simulation space of the Monte Carlo study is composed of 288 different combinations of balanced and unbalanced sample sizes, number of groups, treatment effects, various levels of heterogeneity of variances, dependence between subgroup levels, and skewed error distributions under the single factor experimental design. By this large simulation space, we present a detailed analysis of effects of the violations of assumptions on the performance of nonparametric multiple comparison tests in terms of three error and four power measures. Observations of this study are beneficial to decide the optimal nonparametric test according to requirements and conditions of undertaken experiments. When some of the assumptions of analysis of variance are violated and number of groups is small, use of stepwise Steel-Dwass procedure with Holm's approach is appropriate to control type I error at a desired level. Dunn's method should be employed for greater number of groups. When subgroups are unbalanced and number of groups is small, Nemenyi's procedure with Duncan's approach produces high power values. Conover's procedure successfully provides high power values with a small number of unbalanced groups or with a greater number of balanced or unbalanced groups. At the same time, Conover's procedure is unable to control type I error rates.

Nutritional content of bat-consumed fruits in a forest fragment in Southern Brazil.

The State Park Mata dos Godoy has 42 identified bat species, among which 21 are frugivorous and belong to the Phyllostomidae family. Current study investigated the concentrations of carbohydrate, lipid and protein in fruits consumed by Artibeus lituratus, Carollia perspicillata and Sturnira lilium to understand their potential differentiated food preferences. The Sampling effort it was from April/2013 to March/2014. Animals captured in mist nets were identified in the field and maintained in cotton bags for 30 minutes to defecate. The diet was inferred from fecal samples analyzed in the laboratory, the fruits whose seeds were found in the feces had the determinations of the nutrients accomplished by centesimal composition method. Kruskal-Wallis test and Dunn's multiple comparison method verified the most abundant nutrients for each species of bat. Whereas Carollia perspicillata and Sturnira lilium feeds mainly in food with carbohydrates that provide them with more energy, the diet of Artibeus lituratus is richer in carbohydrates and lipids. Only fruits considered scarcely represent a complete nutrition for the three bat species, however, the complementarity with other food items such as leaves, pollen, and insects, can provide a complete nutrient diet for these animals.

Ultrastructural evaluation of enamel surface morphology after tooth bleaching followed by the application of protective pastes.

The aim of the present in vitro study was to evaluate the morphology of bleached enamel surface followed by the application of different protective pastes. Specimens were prepared from 50 human incisors free of caries and defects. The bleaching procedure was performed with 35% hydrogen peroxide (Perfect Bleach Office+). For the remineralization treatment, different protective pastes (Tooth Mousse, MI Paste Plus, Remin Pro, and Profluorid Varnish) were evaluated. Specimens were randomly assigned to 10 groups of 5 specimens each. The specimens were analyzed under scanning electron microscopy. The superficial morphology of enamel was examined and scored as follows: 0, enamel with smooth surface morphology; 1, enamel with slight irregularities; 2, enamel with moderate irregularities; 3, enamel with accentuated irregularities. The photomicrographs were evaluated in a double-blind manner by three examiners, previously calibrated. Results were analyzed by a Kruskal-Wallis nonparametric test, at the significance level of 0.05. Dunn method posttest was applied for multiple comparisons. A different superficial morphology was observed among control group specimens and specimens treated with bleaching agent and protective pastes (p < 0.05). Enamel bleached showed pronounced surface changes and irregularities, significantly different from other groups except for groups 8 (enamel + Perfect Bleach Office+ + Remin Pro) and 10 (enamel + Perfect Bleach Office+ + Profluorid Varnish) (p > 0.05). The application of the tested pastes after bleaching is effective on repairing enamel surface morphology, demonstrating a higher efficacy for the CPP-ACP products compared to fluoridated ones. SCANNING 38:221-226, 2016. © 2015 Wiley Periodicals, Inc.

Characterizing zoonotic disease detection in the United States: who detects zoonotic disease outbreaks & how fast are they detected?

There have been many calls for improved detection of zoonoses; research has not yet characterized zoonotic disease detection in the United States, in humans or animals. This research reviewed "who detects" zoonotic disease outbreaks and "how fast" they are detected. Definitions were operationalized based on existing literature and current practice. An outbreak database was created from publicly available records: Morbidity and Mortality Weekly Reports and ProMed-Mail. Univariate and bivariate statistics--including chi-square tests, Kruskal-Wallis tests, and Dunn's method were used for analysis. From an n = 101, results showed that laboratories (human health) detected 32.7% (n = 33) of the outbreaks; physicians/clinicians (human health) detected 18.8% (n = 19). The median time to was 13 days; mean was 31.7 (range = 0-492). There was a relationship between the type of the entity (laboratory, practitioner, or state agency) and how fast the outbreak was detected; state agencies were slower in detection. There was also a significant relationship between how fast an outbreak was detected and whether the outbreak occurred in multiple regions. This research provides important empirical evidence regarding U.S. zoonotic disease outbreak detection, highlighting the difficulty in rapid detection of multi-state outbreaks and the need for rapid, sensitive diagnostic testing and astute practitioners.

Comparison of Wright's Formula and the Dunn Method for Measuring the Umbilical Arterial Catheter Insertion Length

Umbilical artery catheterization is the standard procedure for arterial access in neonatal intensive care units. An umbilical arterial catheter (UAC) needs to be placed accurately during the initial insertion because malpositioning increases catheter-related complications and subsequent repositioning exposes newborns to unnecessary handling, further radiologic exposure, and an increased risk of infection. To measure the UAC insertion length in newborns, we compared the conventional practice (i.e., the Dunn method) with a new formula: Wright's formula. The study enrolled 119 newborns. A nomogram derived from Dunn was used during the first study period and the new formula devised by Wright (4×birth weight+7cm) was used during the second study period. The catheter tip position on the initial radiograph was evaluated as correct (i.e., T6-T10), overinsertion (i.e., <T6), or underinsertion (i.e.,>T10). The demographic profiles were not different between the two groups, which included sex; birth weight; and the number of preterm births, low-birth-weight (LBW) newborns,and very-low-birth-weight (VLBW) newborns. When using Wright's formula and the Dunn method, 83% of newborns and 61% of newborns, respectively, received a correct insertion (p<0.05). The success rate for positioning the UAC tip between T7 and T8 was approximately two-fold higher when using Wright's formula than when using the Dunn method. In particular, the rateof correct insertion was significantly higher with Wright's formula in term newborns, LBW newborns, VLBW newborns, and small for gestational age (SGA) newborns (p<0.05); however,the rate of overinsertion with the Dunn method was much higher in term newborns, LBW newborns, VLBW newborns, and SGA newborns (p<0.05). The use of Wright's formula overall results in superior correct placement of the UAC tip. It may be a more accurate and practical method than the conventional practice for measuring the UAC insertion length in newborns.

Acute, unstable, slipped capital femoral epiphysis: is there a role for in situ fixation?

Slipped capital femoral epiphysis, a common disorder in adolescents, may be increasing in incidence in North America because of the obesity epidemic. In most cases, the slip is mild and can be treated with in situ fixation. Even in more severe cases of a stable slip, in situ fixation remains a widely accepted choice. When the slip is acute and unstable, treatment remains controversial. We reviewed the orthopaedic literature and our personal experience in managing acute, unstable slipped capital femoral epiphysis. The reported range of avascular necrosis (AVN) is high and the literature shows no clear recommendations for the best treatment choice. Treatment choices include: in situ stabilization with possible later corrective osteotomy, formal manipulative closed reduction plus screw fixation, partial reduction through an open approach with the hip joint decompressed (Parsch method), and anatomic reduction by the modified Dunn method. Review of the literature and our experience suggests a high AVN rate in acute unstable slips no matter what treatment method is selected. Most North American reports suggest an AVN rate with in situ screw fixation ranging from 20% to 50%. The method described by Parsch, which includes an urgent, open capsulotomy, joint decompression, and gentle partial reduction, shows a low AVN rate as reported from his institution (<10%). The AVN rate reported for anatomic reduction (modified Dunn procedure) performed through an open surgical hip dislocation was initially quite low, but after being restudied in North American centers appears to be about 25%. Safe treatment of an acute unstable slip remains problematic. The literature suggests that these patients should be treated urgently; however, simple in situ stabilization results in a high AVN rate. A likely safer modification is to open the hip anteriorly to decompress the joint and to stabilize after partial reduction as described by Parsch. The modified Dunn method is becoming more widely used, but results in North American centers cite a significant AVN rate.

Acid etching concentration as a strategy to improve the adhesive performance on Er:YAG laser and bur-prepared demineralized enamel.

This study investigated the effect of phosphoric acid concentration on microshear bond strength (μSBS) of an etch-and-rinse adhesive system to demineralized irradiated enamel. Er:YAG laser irradiation may increase acid resistance of enamel; however, its use is associated with reduced bonding effectiveness. Three experimental etching agents and one bonding agent were fabricated. Enamel pretreatment was tested in two levels (bur and laser) and phosphoric acid was tested in four levels (control and at 35, 45, or 55%). Commercially available phosphoric acid and a bonding agent were used as control. Enamel samples were submitted to a pH-cycling model to induce demineralization. Half of the exposed demineralized enamel area was prepared with diamond bur and half was prepared with an Er:YAG laser (λ=2.94 μm, 300 mJ, 2 Hz). Specimens were randomly allocated to receive different acid etching concentrations and either the experimental or the commercial adhesive system. Microshear bond strength and the adhesive remnant index (ARI) scores were determined. μSBS's data were evaluated by two way analysis of variance (ANOVA) and Tukey's test. Kruskal-Wallis followed by Dunn's method and Mann-Whitney test were used for ARI comparisons (α=5%). For μSBS, no significant difference among the groups was found, either for phosphoric acid concentration or surface preparation. For ARI scores, statistically higher resin retention was found for lased groups (p<0.001). The increase of phosphoric acid concentration did not impair bond strength regardless of surface preparation; however, increased retention was found when demineralized enamel was prepared with laser.

Coefficient of energy balance, a new parameter for basic investigation of the cerebrospinal fluid

The concentrations of glucose and lactate in cerebrospinal fluid (CSF) provide important information about energy metabolism in the CSF compartment. To improve our understanding of this information we introduced a new parameter resulting from a formula for calculating the fictitious production of adenosine triphosphate, i.e., the coefficient of energy balance (KEB). We evaluated cytology, the concentrations of glucose and lactate and the KEB in the CSF of 948 patients, who were divided into five groups. For statistical analysis we used the Kruskal-Wallis test with post-hoc analysis using the Dunn method and multinomial regression analysis. We determined the specificities and sensitivities of the cytological pictures and the KEB. A KEB>28.0 corresponded to normal energy metabolism in the CSF. A KEB<28.0 corresponded to an increased level of anaerobic metabolism in the CSF during inflammation in the CNS. A KEB<10.0 corresponded to a high level of anaerobic metabolism in the CSF during severe inflammation with an oxidative burst of professional phagocytes in the CNS. The KEB parameter increased the specificities of cytological examinations of the CSF in all cases. The KEB represents an equation for calculating the fictitious average number of ATP molecules produced in the CSF compartment from one molecule of glucose, and we used it successfully as a new parameter for evaluating energy metabolism status in the CSF.

The influence of cervical spinal cord compression and vertebral displacement on somatosympathetic reflexes in the rat

Background contextOne theory within chiropractic proposes that vertebral subluxation in the upper cervical region induces spinal cord compression sufficient to alter spinal cord efferent output. We report on the feasibility of three different experimental approaches to test this theory. MethodsA high threshold electrical-evoked somatosympathetic reflex was recorded in adrenal or renal nerves of 10 anaesthetized adult male rats before and after (1) graded pressure was applied directly to the C1/C2 spinal cord segment in eight rats by the use of either direct compression or inflation of an extradural balloon and (2) displacement, less than a dislocation applied posterior to anterior, to the C2 vertebra in two rats. The latency and amplitude of the pre- and postintervention reflex responses were compared. ResultsThe reflex amplitude was not significantly changed by pressure (26 mmHg) from an extra-dural balloon or direct compression of the dura mater onto the dorsal spinal cord. Additional pressure, at least sufficient to occlude the dorsal vessels, induced a significant reduction in the amplitude of the reflex, and this reduction persisted for 20 minutes after removal of the pressure (Dunn's method for all pairwise multiple comparison Q stat=3.437; critical value for k=6 with α=0.05 is 2.936). Maximal vertebral (C2) displacement (4 mm), without dislocation did not induce significant changes compared with the control period. ConclusionsAlthough this feasibility study suggests it is unlikely that upper cervical vertebral subluxation, displacement less than a dislocation, compromises the sympathetic outflow in the adrenal or renal nerves, further vertebral displacement studies are necessary to formally test this.

Comparison of the accuracy for three dental impression techniques and index: An in vitro study

ObjectivesThis in vitro study compared the dimensional accuracy of stone index (I) and three impression techniques: tapered impression copings (T), squared impression copings (S) and modified squared impression copings (MS) for implant-supported prostheses. MethodsA master cast, with four parallel implant abutment analogs and a passive framework, were fabricated. Vinyl polysiloxane impression material was used for all impressions with two metal stock trays (open and closed tray). Four groups (I, T, S and MS) were tested (n=5). A metallic framework was seated on each of the casts, one abutment screw was tightened, and the gap between the analog of implant and the framework was measured with a stereomicroscope. The groups’ measurements (80 gap values) were analyzed using software (LeicaQWin – Leica Imaging Systems Ltd.) that received the images of a video camera coupled to a Leica stereomicroscope at 100× magnification. The results were statistically analyzed with Kruskal–Wallis One Way ANOVA on Ranks test followed by Dunn's Method, 0.05. ResultsThe mean values of abutment/framework interface gaps were: Master Cast=32μm (SD 2); Group I=45μm (SD 3); Group T=78μm (SD 25); Group S=134μm (SD 30); Group MS=143μm (SD 27). No significant difference was detected among Index and Master Cast (P=.05). ConclusionUnder the limitations of this study, it could be suggested that a more accurate working cast is possible using tapered impression copings techniques and stone index.

The K + channel GIRK2 is both necessary and sufficient for peripheral opioid‐mediated analgesia

The use of opioid agonists acting outside the central nervous system (CNS) is a promising therapeutic strategy for pain control that avoids deleterious central side effects such as apnea and addiction. In human clinical trials and rat models of inflammatory pain, peripherally restricted opioids have repeatedly shown powerful analgesic effects; in some mouse models however, their actions remain unclear. Here, we investigated opioid receptor coupling to K+ channels as a mechanism to explain such discrepancies. We found that GIRK channels, major effectors for opioid signalling in the CNS, are absent from mouse peripheral sensory neurons but present in human and rat. In vivo transgenic expression of GIRK channels in mouse nociceptors established peripheral opioid signalling and local analgesia. We further identified a regulatory element in the rat GIRK2 gene that accounts for differential expression in rodents. Thus, GIRK channels are indispensable for peripheral opioid analgesia, and their absence in mice has profound consequences for GPCR signalling in peripheral sensory neurons.GIRK channels are indispensable for peripheral opioid analgesia. The absence of GIRK channels from mouse dorsal root ganglion neurons questions the predictive validity of mice as a model organism for investigating peripheral GPCRmediated analgesia.

Potential of coconut water and soy milk for use as storage media to preserve the viability of periodontal ligament cells: an in vitro study

There is no consensus regarding the ability of coconut water and soy milk to maintain long-term cell viability. This study investigated the ability of pH-adjusted coconut water and soy milk to maintain the viability of periodontal ligament cells over a short and a longer period and compared these abilities with those of other solutions. Dog premolar teeth were extracted, dried for 30min, and stored in the following media for 50min or 24h: long shelf-life whole milk (SWM), long shelf-life skim milk (SSM), Hank's Balanced Salt Solution (HBSS), soy milk (SM), and pH-adjusted coconut water (CW). The positive and two negative control groups corresponded to 0-min, 30-min (short-term), and 24-h (long-term) dry times, respectively. Cell viability was analyzed by trypan blue exclusion. Data were statistically analyzed using the Kruskal-Wallis test with post-analysis using the Dunn method. In the short-term experiment, the SSM resulted in significantly lower cell viability than SM and CW. At 24h, SM and CW resulted in higher viability than HBSS and SSM and in comparable performance with the positive control group. Cell viability decreased over time, except in SM and CW. Soy milk and pH-adjusted coconut water showed promising results as storage solutions for avulsed teeth, preserving the viability for up to 24h.