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Reva Schneider1, Ayman Barakat1, John Pippen1,2,3, Cynthia Osborne1,2,3 1Medical Oncology, Baylor-Sammons Cancer Center, 2Texas Oncology PA, 3US Oncology, Dallas, TX, USA Abstract: Estrogen and its metabolites play a significant role in the proliferation of hormone receptor-positive breast cancer. In postmenopausal women, aromatase inhibitors can significantly reduce estrogen levels by blocking enzyme-mediated estrogen synthesis within tissues. Third-generation aromatase inhibitors have now surpassed tamoxifen as first-line therapy for postmenopausal women with metastatic, hormone receptor-positive, breast cancer, showing improved response rates and time to progression. Aromatase inhibitors have shown incremental improvements in disease-free survival, lower local recurrence rates, lower metastatic recurrence rates, and a lower incidence of contralateral breast cancer over tamoxifen when used in the adjuvant setting. Aromatase inhibitors are recommended to be used as adjuvant therapy within the first 5 years of hormonal therapy and may be used either upfront for 5 years or sequenced with tamoxifen. No superiority of one aromatase inhibitor over another has yet been shown. The side effect profiles of aromatase inhibitors have some key differences compared with tamoxifen. These differences may influence treatment choices as well as impact compliance. Keywords: aromatase inhibitor, breast cancer, postmenopausal, hormonal therapy

Apiculate yeasts from Hanseniaspora genus are predominant on the native flora of grapevines, while Hanseniaspora uvarum is well known for its abundant presence in grapes, it results generally, in detrimental quality effects on wine due to high production of acetic acid. By contrast, Hanseniaspora vineae is better adapted to fermentation, increasing flavor complexity in wines as it has been demonstrated in winemaking practices during the last decade. We obtained a collection of more than 22 different Hanseniaspora vineae strains from which we could detect, by a plating screening method, high and moderate protease activity. In this study, we tested these strains under real winemaking conditions on a Sauvignon blanc white wine must. Results obtained demonstrated that there is an interesting protease active diversity in all H. vineae strains when compared to conventional fermentations conducted by Saccharomyces cerevisiae. Four H. vineae strains showed a decrease in wine protein turbidity, up to three times lower than that observed in S. cerevisiae, which imply a significant decrease in the demand for bentonite before bottling. This attribute of some H. vineaestrains should be very attractive at the commercial level to reduce manipulations and flavor removal in the production of delicate white wines such as Sauvignon blanc.

Trauma, infection, malignancy--all can cause scrotal pain and swelling. Or symptoms may signal testicular torsion, a crisis that can destroy the gland within hours of onset. This is a diagnosis not to miss. [ABSTRACT FROM AUTHOR]

The first three causes to think of are obstruction, obstruction, and obstruction -- and you'll be on target in the vast majority of cases. But sometimes you may need to look a bit further. [ABSTRACT FROM AUTHOR]

Abstract Background Bioinformatics and high-throughput technologies such as microarray studies allow the measure of the expression levels of large numbers of genes simultaneously, thus helping us to understand the molecular mechanisms of various biological processes in a cell. Findings We calculate the Pearson Correlation Coefficient (r-value) between probe set signal values from Affymetrix Human Genome Microarray samples and cluster the human genes according to the r-value correlation matrix using the Neighbour Joining (NJ) clustering method. A hyper-geometric distribution is applied on the text annotations of the probe sets to quantify the term overrepresentations. The aim of the tool is the identification of closely correlated genes for a given gene of interest and/or the prediction of its biological function, which is based on the annotations of the respective gene cluster. Conclusion Human Gene Correlation Analysis (HGCA) is a tool to classify human genes according to their coexpression levels and to identify overrepresented annotation terms in correlated gene groups. It is available at: http://biobank-informatics.bioacademy.gr/coexpression/.

Abstract Background Elucidating the genotype-phenotype connection is one of the big challenges of modern molecular biology. To fully understand this connection, it is necessary to consider the underlying networks and the time factor. In this context of data deluge and heterogeneous information, visualization plays an essential role in interpreting complex and dynamic topologies. Thus, software that is able to bring the network, phenotypic and temporal information together is needed. Arena3D has been previously introduced as a tool that facilitates link discovery between processes. It uses a layered display to separate different levels of information while emphasizing the connections between them. We present novel developments of the tool for the visualization and analysis of dynamic genotype-phenotype landscapes. Results Version 2.0 introduces novel features that allow handling time course data in a phenotypic context. Gene expression levels or other measures can be loaded and visualized at different time points and phenotypic comparison is facilitated through clustering and correlation display or highlighting of impacting changes through time. Similarity scoring allows the identification of global patterns in dynamic heterogeneous data. In this paper we demonstrate the utility of the tool on two distinct biological problems of different scales. First, we analyze a medium scale dataset that looks at perturbation effects of the pluripotency regulator Nanog in murine embryonic stem cells. Dynamic cluster analysis suggests alternative indirect links between Nanog and other proteins in the core stem cell network. Moreover, recurrent correlations from the epigenetic to the translational level are identified. Second, we investigate a large scale dataset consisting of genome-wide knockdown screens for human genes essential in the mitotic process. Here, a potential new role for the gene lsm14a in cytokinesis is suggested. We also show how phenotypic patterning allows for extensive comparison and identification of high impact knockdown targets. Conclusions We present a new visualization approach for perturbation screens with multiple phenotypic outcomes. The novel functionality implemented in Arena3D enables effective understanding and comparison of temporal patterns within morphological layers, to help with the system-wide analysis of dynamic processes. Arena3D is available free of charge for academics as a downloadable standalone application from: http://arena3d.org/.

Abstract Background Keeping up-to-date with bioscience literature is becoming increasingly challenging. Several recent methods help meet this challenge by allowing literature search to be launched based on lists of abstracts that the user judges to be 'interesting'. Some methods go further by allowing the user to provide a second input set of 'uninteresting' abstracts; these two input sets are then used to search and rank literature by relevance. In this work we present the service 'Caipirini' (http://caipirini.org) that also allows two input sets, but takes the novel approach of allowing ranking of literature based on one or more sets of genes. Results To evaluate the usefulness of Caipirini, we used two test cases, one related to the human cell cycle, and a second related to disease defense mechanisms in Arabidopsis thaliana. In both cases, the new method achieved high precision in finding literature related to the biological mechanisms underlying the input data sets. Conclusions To our knowledge Caipirini is the first service enabling literature search directly based on biological relevance to gene sets; thus, Caipirini gives the research community a new way to unlock hidden knowledge from gene sets derived via high-throughput experiments.

Abstract Background Protein-Protein interactions (PPI) play a key role in determining the outcome of most cellular processes. The correct identification and characterization of protein interactions and the networks, which they comprise, is critical for understanding the molecular mechanisms within the cell. Large-scale techniques such as pull down assays and tandem affinity purification are used in order to detect protein interactions in an organism. Today, relatively new high-throughput methods like yeast two hybrid, mass spectrometry, microarrays, and phage display are also used to reveal protein interaction networks. Results In this paper we evaluated four different clustering algorithms using six different interaction datasets. We parameterized the MCL, Spectral, RNSC and Affinity Propagation algorithms and applied them to six PPI datasets produced experimentally by Yeast 2 Hybrid (Y2H) and Tandem Affinity Purification (TAP) methods. The predicted clusters, so called protein complexes, were then compared and benchmarked with already known complexes stored in published databases. Conclusions While results may differ upon parameterization, the MCL and RNSC algorithms seem to be more promising and more accurate at predicting PPI complexes. Moreover, they predict more complexes than other reviewed algorithms in absolute numbers. On the other hand the spectral clustering algorithm achieves the highest valid prediction rate in our experiments. However, it is nearly always outperformed by both RNSC and MCL in terms of the geometrical accuracy while it generates the fewest valid clusters than any other reviewed algorithm. This article demonstrates various metrics to evaluate the accuracy of such predictions as they are presented in the text below. Supplementary material can be found at: http://www.bioacademy.gr/bioinformatics/projects/ppireview.htm

Abstract Background Biological processes such as metabolic pathways, gene regulation or protein-protein interactions are often represented as graphs in systems biology. The understanding of such networks, their analysis, and their visualization are today important challenges in life sciences. While a great variety of visualization tools that try to address most of these challenges already exists, only few of them succeed to bridge the gap between visualization and network analysis. Findings Medusa is a powerful tool for visualization and clustering analysis of large-scale biological networks. It is highly interactive and it supports weighted and unweighted multi-edged directed and undirected graphs. It combines a variety of layouts and clustering methods for comprehensive views and advanced data analysis. Its main purpose is to integrate visualization and analysis of heterogeneous data from different sources into a single network. Conclusions Medusa provides a concise visual tool, which is helpful for network analysis and interpretation. Medusa is offered both as a standalone application and as an applet written in Java. It can be found at: https://sites.google.com/site/medusa3visualization.

Abstract Understanding complex systems often requires a bottom-up analysis towards a systems biology approach. The need to investigate a system, not only as individual components but as a whole, emerges. This can be done by examining the elementary constituents individually and then how these are connected. The myriad components of a system and their interactions are best characterized as networks and they are mainly represented as graphs where thousands of nodes are connected with thousands of vertices. In this article we demonstrate approaches, models and methods from the graph theory universe and we discuss ways in which they can be used to reveal hidden properties and features of a network. This network profiling combined with knowledge extraction will help us to better understand the biological significance of the system.

Abstract The quantities of data obtained by the new high-throughput technologies, such as microarrays or ChIP-Chip arrays, and the large-scale OMICS-approaches, such as genomics, proteomics and transcriptomics, are becoming vast. Sequencing technologies become cheaper and easier to use and, thus, large-scale evolutionary studies towards the origins of life for all species and their evolution becomes more and more challenging. Databases holding information about how data are related and how they are hierarchically organized expand rapidly. Clustering analysis is becoming more and more difficult to be applied on very large amounts of data since the results of these algorithms cannot be efficiently visualized. Most of the available visualization tools that are able to represent such hierarchies, project data in 2D and are lacking often the necessary user friendliness and interactivity. For example, the current phylogenetic tree visualization tools are not able to display easy to understand large scale trees with more than a few thousand nodes. In this study, we review tools that are currently available for the visualization of biological trees and analysis, mainly developed during the last decade. We describe the uniform and standard computer readable formats to represent tree hierarchies and we comment on the functionality and the limitations of these tools. We also discuss on how these tools can be developed further and should become integrated with various data sources. Here we focus on freely available software that offers to the users various tree-representation methodologies for biological data analysis.

Abstract Background Biological knowledge is represented in scientific literature that often describes the function of genes/proteins (bioentities) in terms of their interactions (biointeractions). Such bioentities are often related to biological concepts of interest that are specific of a determined research field. Therefore, the study of the current literature about a selected topic deposited in public databases, facilitates the generation of novel hypotheses associating a set of bioentities to a common context. Results We created a text mining system (LAITOR: Literature Assistant for Identification of Terms co-Occurrences and Relationships) that analyses co-occurrences of bioentities, biointeractions, and other biological terms in MEDLINE abstracts. The method accounts for the position of the co-occurring terms within sentences or abstracts. The system detected abstracts mentioning protein-protein interactions in a standard test (BioCreative II IAS test data) with a precision of 0.82-0.89 and a recall of 0.48-0.70. We illustrate the application of LAITOR to the detection of plant response genes in a dataset of 1000 abstracts relevant to the topic. Conclusions Text mining tools combining the extraction of interacting bioentities and biological concepts with network displays can be helpful in developing reasonable hypotheses in different scientific backgrounds.

Abstract The analysis and interpretation of relationships between biological molecules, networks and concepts is becoming a major bottleneck in systems biology. Very often the pure amount of data and their heterogeneity provides a challenge for the visualization of the data. There are a wide variety of graph representations available, which most often map the data on 2D graphs to visualize biological interactions. These methods are applicable to a wide range of problems, nevertheless many of them reach a limit in terms of user friendliness when thousands of nodes and connections have to be analyzed and visualized. In this study we are reviewing visualization tools that are currently available for visualization of biological networks mainly invented in the latest past years. We comment on the functionality, the limitations and the specific strengths of these tools, and how these tools could be further developed in the direction of data integration and information sharing.

Abstract Background Modern proteomes evolved by modification of pre-existing ones. It is extremely important to comparative biology that related proteins be identified as members of the same cognate group, since a characterized putative homolog could be used to find clues about the function of uncharacterized proteins from the same group. Typically, databases of related proteins focus on those from completely-sequenced genomes. Unfortunately, relatively few organisms have had their genomes fully sequenced; accordingly, many proteins are ignored by the currently available databases of cognate proteins, despite the high amount of important genes that are functionally described only for these incomplete proteomes. Results We have developed a method to cluster cognate proteins from multiple organisms beginning with only one sequence, through connectivity saturation with that Seed sequence. We show that the generated clusters are in agreement with some other approaches based on full genome comparison. Conclusion The method produced results that are as reliable as those produced by conventional clustering approaches. Generating clusters based only on individual proteins of interest is less time consuming than generating clusters for whole proteomes.

Abstract Background Aseptic loosening of hip prosthesis as it occurs in clinical cases in human patients was attributed to wear particles of the implants, the response of the tissue dominated by macrophages and the production of inflammatory mediators and matrix degrading enzymes; however, the cascade of events initiating the process and their interaction regarding the time course is still open and discussed controversially. Therefore, the goal of this study was to establish an experimental animal model in sheep allowing to follow the cascade of early mechanical and biochemical events within the interface membrane and study the sequence of how they contribute to the pathological bone resorption necessary for aseptic loosening of the implant. Methods A cemented modular system (Biomedtrix) was used as a hip replacement in 24 adult Swiss Alpine sheep, with one group receiving a complete cement mantle as controls (n = 12), and the other group a cement mantle with a standardized, lateral, primary defect in the cement mantle (n = 12). Animals were followed over time for 2 and 8.5 months (n = 6 each). After sacrifice, samples from the interface membranes were harvested from five different regions of the femur and joint capsule. Explant cell cultures were performed and supernatant of cultures were tested and assayed for nitric oxide, prostaglandin E2, caseinolytic and collagenolytic activity. RNA extraction and quantification were performed for inducible nitric oxide synthase, cyclooxygenase-2, interleukin 1, and interleukin 6. Overall differences between groups and time periods and interactions thereof were calculated using a factorial analysis of variance (ANOVA). Results The development of an interface membrane was noticed in both groups at both time points. However, in the controls the interface membrane regressed in thickness and biological activity, while both variables increased in the experimental group with the primary cement mantle defect over time. Nitric oxide (NO) and PGE2 concentrations were higher in the 8.5 months group (P < 0.0001) compared to the 2 months group with a tendency for the unstable group to have higher concentrations. The same was true for collagenolytic activity (P = 0.05), but not for caseinolytic activity that decreased over time (P < 0.0001). Conclusion In this study, a primary cement mantle defect of the femoral shaft elicited biomechanical instability and biochemical changes over time in an experimental animal study in sheep, that resembled the changes described at the bone cement-interface in aseptic loosening of total hip prosthesis in humans. The early biochemical changes may well explain the pathologic bone resorption and formation of an interface membrane as is observed in clinical cases. This animal model may aid in future studies aiming at prevention of aseptic loosening of hip prosthesis and reflect some aspects of the pathogenesis involved.

Background: Advanced maternal age is associated with higher frequencies of antenatal and perinatal conditions, as well as a higher risk of cerebral palsy in offspring. We explore the association between maternal age and specific cerebral palsy risk factors., Methods: Data were extracted from the Canadian Cerebral Palsy Registry. Maternal age was categorized as ≥35 years of age and less than 20 years of age at the time of birth. Chi-square and multivariate logistic regressions were performed to calculate odds ratios and their 95% confidence intervals., Results: The final sample consisted of 1391 children with cerebral palsy, with 19% of children having mothers aged 35 or older and 4% of children having mothers below the age of 20. Univariate analyses showed that mothers aged 35 or older were more likely to have gestational diabetes (odds ratio 1.9, 95% confidence interval 1.3 to 2.8), to have a history of miscarriage (odds ratio 1.8, 95% confidence interval 1.3 to 2.4), to have undergone fertility treatments (odds ratio 2.4, 95% confidence interval 1.5 to 3.9), and to have delivered by Caesarean section (odds ratio 1.6, 95% confidence interval 1.2 to 2.2). These findings were supported by multivariate analyses. Children with mothers below the age of 20 were more likely to have a congenital malformation (odds ratio 2.4, 95% confidence interval 1.4 to 4.2), which is also supported by multivariate analysis., Conclusions: The risk factor profiles of children with cerebral palsy vary by maternal age. Future studies are warranted to further our understanding of the compound causal pathways leading to cerebral palsy and the observed greater prevalence of cerebral palsy with increasing maternal age., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The human pathogen Trichomonas vaginalis lacks conventional mitochondria and instead contains divergent mitochondrial-related organelles. These double-membrane bound organelles, called hydrogenosomes, produce molecular hydrogen. Phylogenetic and biochemical analyses of hydrogenosomes indicate a common origin with mitochondria; however identification of hydrogenosomal proteins and studies on its metabolism have been limited. Here we provide a detailed proteomic analysis of the T. vaginalis hydrogenosome. The proteome of purified hydrogenosomes consists of 569 proteins, a number substantially lower than the 1,000-1,500 proteins reported for fungal and animal mitochondrial proteomes, yet considerably higher than proteins assigned to mitosomes. Pathways common to and distinct from both mitochondria and mitosomes were revealed by the hydrogenosome proteome. Proteins known to function in amino acid and energy metabolism, Fe-S cluster assembly, flavin-mediated catalysis, oxygen stress response, membrane translocation, chaperonin functions, proteolytic processing and ATP hydrolysis account for ∼30% of the hydrogenosome proteome. Of the 569 proteins in the hydrogenosome proteome, many appear to be associated with the external surface of hydrogenosomes, including large numbers of GTPases and ribosomal proteins. Glycolytic proteins were also found to be associated with the hydrogenosome proteome, similar to that previously observed for mitochondrial proteomes. Approximately 18% of the hydrogenosomal proteome is composed of hypothetical proteins of unknown function, predictive of multiple activities and properties yet to be uncovered for these highly adapted organelles., (Copyright © 2011. Published by Elsevier Ltd.)

Background: Roux-en-Y gastric bypass (RYGB) restricts food intake, and when the Roux limb is elongated to 150 cm, the procedure is believed to induce malabsorption., Objective: Our objective was to measure total reduction in intestinal absorption of combustible energy after RYGB and the extent to which this was due to restriction of food intake or malabsorption of ingested macronutrients., Design: Long-limb RYGB was performed in 9 severely obese patients. Dietary intake and intestinal absorption of fat, protein, carbohydrate, and combustible energy were measured before and at 2 intervals after bypass. By using coefficients of absorption to measure absorptive function, equations were developed to calculate the daily gram and kilocalorie quantities of ingested macronutrients that were not absorbed because of malabsorption or restricted food intake., Results: Coefficients of fat absorption were 92 ± 1.3% before bypass, 72 ± 5.5% 5 mo after bypass, and 68 ± 8.7% 14 mo after bypass. There were no statistically significant effects of RYGB on protein or carbohydrate absorption coefficients, although protein coefficients decreased substantially in some patients. Five months after bypass, malabsorption reduced absorption of combustible energy by 124 ± 57 kcal/d, whereas restriction of food intake reduced energy absorption by 2062 ± 271 kcal/d. Fourteen months after bypass, malabsorption reduced energy absorption by 172 ± 60 kcal/d compared with 1418 ± 171 kcal/d caused by restricted food intake., Conclusion: On average, malabsorption accounted for ≈6% and 11% of the total reduction in combustible energy absorption at 5 and 14 mo, respectively, after this gastric bypass procedure.

Cystic fibrosis (CF) is now an adult disease. Approximately 30,000 children and adults are affected by this disease. CF, an autosomal recessive disease, is considered to be the most lethal inherited trait among Caucasians. The median age for the CF patient has significantly increased over the past 60 years. Today's oral and maxillofacial surgery practice is likely to include patients with CF with varying surgical needs. This article will review diagnosis, pathophysiology, and systemic complications of CF, and discuss relevant information for management of the CF patient for the oral and maxillofacial surgeon. Recommendations will be made for preoperative, perioperative, and postoperative care of these patients.

An abundant integral membrane protein, Hmp35, has been isolated from hydrogenosomes of Trichomonas vaginalis. This protein has no known homologue and exists as a stable 300-kDa complex, termed HMP35, in membranes of the hydrogenosome. By using blue native gel electrophoresis, we found the HMP35 complex to be stable in 2 m NaCl and up to 5 m urea. The endogenous Hmp35 protein was largely protease-resistant. The protein has a predominantly beta-sheet structure and predicted transmembrane domains that may form a pore. Interestingly, the protein has a high number of cysteine residues, some of which are arranged in motifs that resemble the RING finger, suggesting that they could be coordinating zinc or another divalent cation. Our data show that Hmp35 forms one intramolecular but no intermolecular disulfide bonds. We have isolated the HMP35 complex by expressing a His-tagged Hmp35 protein in vivo followed by purification with nickel-agarose beads. The purified 300-kDa complex consists of mostly Hmp35 with lesser amounts of 12-, 25-27-, and 32-kDa proteins. The stoichiometry of proteins in the complex indicates that Hmp35 exists as an oligomer. Hmp35 can be targeted heterologously into yeast mitochondria, despite the lack of homology with any yeast protein, demonstrating the compatibility of mitochondrial and hydrogenosomal protein translocation machineries.

Objectives: Rapid-sequence intubation (RSI) is an active airway intervention used frequently in emergency medicine (EM). The authors hypothesized that RSI can be performed safely in the setting of an EM training program at a tertiary care center., Methods: Observational study of RSI at an urban ED/Level 1 trauma center with annual census of 100,000 patients. Consecutive patients who underwent RSI during a two-year period were studied. Data included age, gender, type of patient (medical/trauma), indication for intubation, number of intubation attempts (laryngoscope passes), training level of operator, and major immediate adverse events (clinical deterioration within 10 minutes of RSI)., Results: RSI was used in 417 of 596 (70%) critically ill patients requiring emergent intubation. The patient demographic distribution was the following: adults 89.7%, male 58%, and trauma 44%. Primary indications for intubation among RSI patients were as follows: mechanical ventilation 57.4%, airway protection 41.3%, and cardiac arrest 1.3%. Distribution of intubations by level of EM training was PGY1, 5%; PGY2, 52%; PGY3, 40%; and attendings, 3%. Intubations were successfully completed within two attempts in 97% of the patients. Major immediate adverse events were encountered in six patients (1.4%) (hypotention=2, hypoxemia=1, dysrhythmia=3). There was no death attributable to RSI. The rate of intubations requiring two or fewer attempts and without major immediate adverse events was 96%. Three patients required cricothyrotomy., Conclusion: In the setting of an EM residency at a tertiary care ED, RSI can be performed successfully with few major immediate adverse events.

The purpose of this article is to describe the neural anatomy of the temporalis muscle as dissected along the intramuscular temporal fascial plane. This sagittal plane is a natural cleavage plane of the muscle, which is explored along with its relationship to the deep temporal nerve. Eight temporalis muscle specimens were removed in their entirety from 8 preserved cadavers. The muscles were selected based on whether they were grossly intact prior to procurement for processing. The muscle specimens were then processed over a 3-month period using Sihler's staining technique. Muscle dissection was performed along the intramuscular fascial plane under an operating microscope, taking care to preserve the underlying nerve and arterial anatomy. Dissections demonstrated an anterior and posterior division of the deep temporal nerve running within the deep portion of the muscle below the intramuscular fascial plane. This fascial layer provided a natural dissection plane to expose and evaluate the underlying nerve and arterial anatomy. In all specimens the deep temporal artery originated with the anterior temporal nerve and then branched into an anterior and posterior division. The innervation density and nerve caliber of the anterior portion of the muscle was much greater than that of the posterior, correlating with a greater anterior muscle bulk. This may have implications in differences in fiber type and functional regionalization of the muscle. The results of this anatomic study support the finding of an anterior and posterior division of the deep temporal nerve within the deep portion of the temporalis muscle. In addition, differences in the innervation density and muscle bulk lend credence to the possibility of regional muscle specialization. The natural cleavage plane of the intramuscular temporal fascia may have clinical ramifications for temporalis myofascial flaps while preserving the underlying neural anatomy to allow for normal residual temporalis muscle function.

Purpose: The purpose of this study was to compare the biomechanical stability of rigidly fixed condylar neck fractures using either a conventional four-hole miniplate system or the Wurzburg lag screw plate system., Materials and Methods: Ten identical synthetic mandibles were used for this study. Simulated bilateral condylar neck fractures were fixed with the lag screw plate system on one side and the miniplate system on the other. The mandibles were loaded with an MTS servohydraulic testing machine at a rate of 1 cm/min until failure was reached. Data for resistance to motion and ultimate strength for each fixation device were compared by paired Student t-tests., Results: The mean resistance to motion for the four-hole miniplate was 64.0 kg/mm (SD = 10.1; range = 52-94) and for the lag screw system was 80.2 kg/mm (SD = 24.0; range = 55 to 126). The mean failure strength was 4.0 kg (SD = 0.9) (range = 2.6 to 5.5) for the miniplate system and 5.0 kg (SD = 2.5; range = 3.4 to 7.2) for the lag screw system. The lag screw system was significantly (P < .05) better than the miniplate for both parameters measured., Conclusion: In laboratory testing using synthetic mandibles, the Wurzburg lag screw-plate fixation system proved superior to a four-hole miniplate system in regard to resistance to motion and failure strength. Clinical trials are necessary to substantiate these laboratory data and determine whether the system can be effectively applied by the surgeon.

Dentigerous cysts are commonly encountered in the practice of dentistry and oral and maxillofacial surgery. Treatment modalities range from enucleation to marsupialization, and are based on the premise that the pathological process can be controlled locally with minimal injury to the adjacent host structures. In a child, however, loss of permanent tooth buds in the management of a large dentigerous cyst can be devastating. This article describes the technique of fenestration, which removes this entity and preserves the developing dentition.

The purpose of this study is to demonstrate an intramuscular fascial layer within the temporalis muscle. This can be used as an inferior plane when developing a temporalis myofascial flap for temporomandibular joint reconstruction. The advantages of using this plane include relatively bloodless zone, adequate thickness of flap for reconstructive purposes, and residual temporalis muscle to prevent the temporal concavity deformity. Cadaveric and clinical examples are presented.

From 1990 to 1992 there was a 43% increase in the number of carotid endarterectomies (CEAs) performed at our institution. Not coincidentally the North American Symptomatic Carotid Endarterectomy Trial study was published in August 1991. To determine whether CEAs could be performed safely at community medical centers, records of 181 consecutive CEAs performed during a 30-month period at a suburban community medical center were reviewed. CEAs were performed by 14 surgeons: six vascular, three thoracic, and five general surgeons. Among all patients 87% had lesions with > or = 70% stenosis. Seventy percent of CEAs were performed on symptomatic patients, 84% of whom had stenoses > or = 70%. Among asymptomatic patients 96% had stenoses > or = 70%. There were five instances of neurologic complications in the perioperative period--two transient ischemic attacks, two reversible ischemic neurologic deficits, and one permanent neurologic deficit. One patient died. The mortality rate was 0.6%, the combined major stroke/mortality rate was 1.2%, and the any stroke/mortality rate was 2.2%. There were five patients with nonfatal major complications--one with myocardial infarction, one with pulmonary edema, one with congestive heart failure, and two with postoperative arrhythmia. Thirteen minor complications included eight cases of cranial nerve dysfunction. These data demonstrate that CEAs can be performed safely at community medical centers.

Evaluation of genitourinary trauma can be confusing. This article discusses identifying the significant injuries, those patients at risk for developing these injuries, and the radiographic procedures that will effectively stage these injuries so that appropriate management can be proposed.

A multicomponent pheromone produced by male cabbage looper moths that is attractive to female moths in a flight tunnel bioassay was isolated and identified. Based on analyses of hairpencil extracts of male cabbage loopers and volatiles emitted by males, the pheromone has been identified as a blend consisting of (S)-(+)-linalool,p-cresol, andm-cresol. The chirality of the major component, (S)-(+)-linalool, is important for behavioral response of females. These pheromonal compounds were also identified as volatiles released by males when males were exposed to the principal pheromone component of female cabbage loopers, (Z)-7-dodecen-1-ol acetate. The amount of male pheromone released was increased significantly when males were exposed to a combination of (Z)-7-dodecen-1-ol acetate and the odor from cabbage. Neither linalool nor the cresols were detected in volatiles from cabbage or from males exposed to cabbage odor.

Pulse oximetry is a noninvasive, accurate, and safe method for the measurement of oxygen saturation during intravenous sedation or general anesthesia. Several factors should be considered with its use, since these variables will either alter the accuracy of the readings or may cause harm to the patient. These factors include changes in the strength of the arterial pulse, body movements, dyshemoglobinemias, plasma lipids and bilirubin, color interferences, venous pulsations, and several physical factors. Awareness of these variations will help the clinician become more knowledgeable in the use of the pulse oximeter.

Previous work has shown that after a single oral dose, plasma propranolol concentrations in patients with active inflammatory disease are significantly higher than those in healthy subjects. After oral administration of propranolol (2 mg) to arthritic rats, the area under the mean drug concentration-time curve in plasma was approximately 10 times greater than that in control animals. After intravenous administration (0.25 mg) the area in arthritic rats was approximately doubled compared with that in controls. The mechanisms causing these changes are not known, but it is probable that increased drug binding to an acute phase reactant in plasma, together with decreased first-pass hepatic clearance in arthritic rats after oral dosing, are involved.