Spatial Position and Anatomical Characteristics Associated with Impacted Third Molars Using a Map-Reading Strategy on Cone-Beam Computed Tomography Scans: A Retrospective Analysis

(1) Background: This study assessed the spatial position and anatomical features associated with impacted third molars through a map-reading strategy employing cone-beam computed tomography (CBCT). (2) Methods: The positioning of impacted third molars on CBCT was assessed using Winter's and Pell and Gregory's classifications. External root resorption in mandibular second molars was categorized according to Herman's classification. Additionally, the relationship between the mandibular third molar root apex and the mandibular canal was examined. Comparative statistical analysis was conducted using Fisher's exact test, with a significance level considered as 5%. (3) Results: The results indicated that, based on Winter's classification, 48.06 % of impacted teeth were positioned mesioangularly. Employing Pell and Gregory's classification, 43.22% of the impacted molars fell into positions B and C, with 54.2% classified as Class II. A notable 69.7% of teeth exhibited no contact between the root apex and the mandibular canal, and external root resorption in the distal aspect of the second molar was absent in 88.7% of cases. (4) Conclusions: Utilizing the map-reading strategy with CBCT scans to assess the anatomical positions and characteristics of impacted third molars enhances professional confidence and sets a standard for quality and safety in the surgical procedure for patients.

Method to determine the root canal spatial geometry using an algorithm of the e-Vol DX CBCT software

This study evaluated a method to determine the spatial geometry of root canal preparation (RCP) using navigation dynamics and a specific algorithm from a new CBCT software (e-Vol DX). CBCT scans of 168 root canals of mandibular molars were acquired before and after RCP, using nickel-titanium (NiTi) instruments (ProTaper Next, BioRace, Reciproc Blue, and WaveOne Gold). The spatial geometry of the root canals and the operative risk of disproportional wear of dentinal walls after RCP were evaluated using a new CBCT software. A 3-point scoring system was used after the measuring of cementum/dentin thickness before and after RCP in all root thirds. The root thirds were distributed into three parts of similar sizes, and the scores were categorized at three levels: 1. mild risk (1/3), 2. moderate risk (2/3), 3. severe risk (3/3). These levels were proposed according to the risk of creating disproportionate shapes, thin walls, or perforations. The data were analyzed statistically by Fischer's exact test (α = 5%). There were no significant differences in operative risk among the NiTi engine-driven systems, for the distal or mesial walls of all the root canal thirds (p>0.05). The spatial geometry method to assess operative risk allows clinical planning for a predictable enlargement of the root canal in all root thirds. Based on using a map-reading strategy on root canals in CBCT scans, NiTi engine-driven instruments did not present an increased operative risk during RCPs.

Evaluation in the danger zone of mandibular molars after root canal preparation using novel CBCT software

This study measured the thickness of cementum/dentin in the danger zone of the mandibular molars after root canal preparation using novel cone-beam computed tomography (CBCT) software. Eighty-four teeth were distributed into four groups: ProTaper Next, BioRace, Reciproc Blue, and WaveOne Gold. E-Vol DX® CBCT software was used to measure initial and final remaining cementum-dentin thicknesses after root canal preparation of the mesial root of mandibular molars at 1 and 3 mm from the furcation. The Kolmogorov-Smirnov test was used to test variable symmetry. The variables were described as mean and standard deviations, compared among the groups using analysis of variance (ANOVA), and within the groups using the Student t test. A generalized estimating equation model was used to compare the variation before and after root canal preparation. The level of significance was set at 5%. Differences between mean initial and final thicknesses of the mesiobuccal (MB) and mesiolingual (ML) canals were not statistically significant. The mean initial thickness was 3 mm (0.900 mm ± 0.191), considering that a mean lower than 1 mm (1.035 mm ± 0.184) indicates the danger zone. Although cementum/dentin is thinner at 3 mm from the furcation (0.715±0.186) after root canal preparation, the greatest amount of dentin removed was found at 1 mm (0.734 ± 0.191). The cementum-dentin remaining after preparation was thicker than 0.715 mm in root canals prepared using #35 (WaveOne Gold®) and #40 (ProTaper Next®, BioRace® and Reciproc Blue®) instruments. This confirms the safety of canal preparation in the danger zone using these systems.

Method to Identify Accessory Root Canals using a New CBCT Software

This study describes a methodology to identify accessory root canals using the e-Vol DX software in CBCT scans. Accessory root canals are strategic shelters for microorganisms present in root canal infections. The identification of these small canals in periapical radiographic exams has limitations, besides being markedly limited accessibility to the action of endodontic instruments and to the antimicrobial agents. A significant number of accessory canals have sufficient diameters to be visible on cone-beam computed tomography (CBCT) images of high spatial resolution. Therefore, it may go unnoticed or even confused when there is no specific training for this type of diagnosis. The methodology consists in establishing thin slices (0.1mm or smaller) obtained from coronal, sagittal and axial slices. The method consists of the following steps: during navigation along the long axis of a root canal when finding a possible hypodense line of main root canal in a tomographic section (axial, sagittal or coronal), the navigation software lines of the multiplanar reconstruction (MPR) must be adjusted so that they are parallel and perpendicular to the hypodense line (parallax correction). Then, after judiciously adjusted, the accessory canal image will invariably appear as a line on one of the MPR tomographic slices, another line on another slice, and a dot on the third slice. The three sections of the MPR present images with the "line-line-dot" sequence. In this way, it is possible to identify an accessory root canal and also visualize it in volumetric reconstruction in a specific filter. The application of this method is easy to employed and may benefit the diagnosis when you want to visualize accessory root canals and distinguish it from root fracture line.

Cone-beam computed tomography cinematic rendering: clinical, teaching and research applications

Cone-beam computed tomography (CBCT) is an essential imaging method that increases the accuracy of diagnoses, planning and follow-up of endodontic complex cases. Image postprocessing and subsequent visualization relies on software for three-dimensional navigation, and application of indexation tools to provide clinically useful information according to a set of volumetric data. Image postprocessing has a crucial impact on diagnostic quality and various techniques have been employed on computed tomography (CT) and magnetic resonance imaging (MRI) data sets. These include: multiplanar reformations (MPR), maximum intensity projection (MIP) and volume rendering (VR). A recent advance in 3D data visualization is the new cinematic rendering reconstruction method, a technique that generates photorealistic 3D images from conventional CT and MRI data. This review discusses the importance of CBCT cinematic rendering for clinical decision-making, teaching, and research in Endodontics, and a presents series of cases that illustrate the diagnostic value of 3D cinematic rendering in clinical care.

Differential diagnosis and clinical management of periapical radiopaque/hyperdense jaw lesions

Great attention has been given to the study of radiolucent periapical lesions to avert possible misdiagnosis of apical periodontitis associated with certain radiolucent non-endodontic lesions. However, there are a significant number of radiopaque lesions found in the periapical region, which could be equally relevant to endodontic practice. The diagnosis and management of these radiopaque/hyperdense lesions could be challenging to the endodontist. These bone alterations could be neoplastic, dysplastic or of metabolic origin. In the context of the more widespread use of cone-beam CT, a detailed review of radiopaque inflammatory and non-inflammatory lesions is timely and may aid clinicians perform a differential diagnosis of these lesions. Distinguishing between inflammatory and non-inflammatory lesions simplifies diagnosis and consequently aids in choosing the correct therapeutic regimen. This review discusses the literature regarding the clinical, radiographic, histological and management aspects of radiopaque/hyperdense lesions, and illustrates the differential diagnoses of these lesions.

Determination of Root Canal Cleanliness by Different Irrigation Methods and Morphometric Analysis of Apical Third

AIM

The aim of this study was to determine the root canal area before and after the instrumentation 1 mm short of the apical foramen by clinical and cone beam computed tomography (CBCT) methods, and to evaluate the cleanliness of the apical region in mesiodistal flattened teeth by using optical microscopy.

MATERIALS AND METHODS

Forty-two human single-canal mandibular incisors were instrumented using the Free Tip Preparation technique up to three, four or five instruments from the initial. Cone beam computed tomography scans were acquired of the samples before and after root canal preparation (RCP). Irrigation was performed by conventional or hydrodynamic means, using 2.5% sodium hypochlorite. The samples were prepared for observation under an optical microscope. Images were digitally obtained, analyzed and the results were submitted to statistical analysis (two-way ANOVA complemented by Bonferroni's post-test).

RESULTS

There was no significant difference between the studied anatomical areas with both CBCT and clinical methods. There were no differences between irrigation methods. It was verified differences between instrumentation techniques. Instrumentation with four instruments from the initial instrument determined a significant increase in the contact area when compared to preparation with three instruments, but RCP with 5 instruments did not result in a better cleanliness.

CONCLUSION

The analysis with CBCT was not capable to determine the precise shape of surgical apical area comparing to the clinical method.

CLINICAL SIGNIFICANCE

Both the conventional and hydrodynamic irrigation techniques were not able to promote root canals debris-free. The instruments action in root canal walls was proportional to the number of instruments used from the initial apical instrument.

Using cone beam computed tomography images to diagnose multiple taurodontisms

Taurodontism is a developmental anomaly that manifests as an alteration in a patient's internal morphology and is characterized by the lack of constriction at the level of the cementoenamel junction, which results in an apical extension of the pulp chamber that extends into the root area of a multiradicular tooth. This report presents a case of an otherwise healthy patient with 12 hypertaurodontic teeth, which were detected by using cone beam computed tomography (CBCT). It is essential to emphasize the importance of routine imaging examinations for diagnosing developmental dental anomalies such as taurodontism, as this condition is generally not found by routine oral examination, and is not necessarily restricted to syndromic patients. CBCT images contribute to the diagnosis of and treatment plan for taurodontism.

Detection of Root Canal Isthmuses in Molars by Map-Reading Dynamic using CBCT images

The aim of this study was to detect root isthmuses in maxillary and mandibular molars and evaluate their frequencies using map-reading dynamics in CBCT images. Two hundred extracted human maxillary and mandibular molars were used in ex vivo assay. A consecutive sample of two hundred maxillary and mandibular molars (first and second) was selected from CBCT exams. The isthmuses were detected from the pulp orifice to the apex and were recorded according to their beginning and their end, into categories: 1. begin and end in cervical third; 2. beginning in cervical third and end in middle third; 3. beginning in cervical third and end in apical third; 4. beginning and end in middle third; 5. begin in middle third and end in apical third; 6. beginning and end in apical third; 7. no isthmus. The scans were obtained in different planes with map-reading in axial slices of 0.5 mm/0.5 mm involved the coronal to apical direction. The frequencies of isthmus were analyzed according to the level of root and evaluated by Chi-square test. The level of significance was set at α=0.05. The presence of isthmus detected in maxillary molars was 86% in ex vivo assay and 62% in vivo assay, whereas in mandibular molars was observed 70% in ex vivo assay and 72% in vivo assay. The frequency of isthmus was high in both study models. The map-reading dynamics in CBCT images was found to be precise to detect the localization of isthmus.

Effect of root canal filling materials on dimensions of cone-beam computed tomography images

Objective

To evaluate the discrepancy of root canal filling (RCF) measurements obtained from original root specimens and cone-beam computed tomography (CBCT) images.

Material and Methods

Seventy-two human maxillary anterior teeth were prepared up to an ISO #50 K-File 1 mm short of the apical foramen. Thus, the teeth were randomly divided into 8 groups, according to the root canal filling material: Sealapex^®, Sealapex^®+gutta-percha points, Sealer 26^®, Sealer 26^®+gutta-percha points, AH PlusTM, AH PlusTM+gutta-percha points, Grossman Sealer, and Grossman Sealer+gutta-percha points. After root canal preparation and RCF, CBCT scans were acquired and the specimens were sectioned in axial, sagittal and coronal planes. The RCF measurements were obtained in different planes and thicknesses to determine the discrepancy between the original root specimens (using a digital caliper) and the CBCT images (using the scanner's proprietary software). One-way analysis of variance and Tukey tests were used for statistical analyses. The significance level was set at α=5%.

Results

Measurements of the different endodontic filling materials were 9% to 100% greater on the CBCT images than on the original root specimens. Greater RCF dimensions were found when only sealers were used, with statistically significant difference among the groups.

Conclusions

RCF dimensions were greater on CBCT images than on the original root specimens, especially when only sealer was used.

Differential diagnosis of apical periodontitis and nasopalatine duct cyst

INTRODUCTION

An accurate differential diagnosis of apical periodontitis (AP) and nasopalatine duct cyst (NPDC) should be established to define the best treatment for endodontically treated maxillary anterior teeth with apical periodontitis. Three-dimensional cone beam computed tomography (CBCT) images help to plan treatment and to define an initial diagnostic hypothesis. However, endodontic treatment or retreatment may be unnecessarily prescribed when radiographs show a superimposition of the incisor foramen over the apex of maxillary central incisors, mimicking AP. Diseases of nonendodontic origin that affect the tooth apex, such as NPDC, should be included in the differential diagnosis.

METHODS AND RESULTS

Four clinical cases of patients with large periapical radiolucencies and similar radiographic features are described. AP is usually a consequence of endodontic infection; in cases of NPDC, however, spontaneous epithelial proliferation, in addition to bacterial infection and trauma, may also contribute to cyst formation. The frequency and recurrence rates of NPDC are low, and its behavior is less aggressive. Surgical enucleation of the periapical lesion is recommended after nonsurgical treatment does not heal AP.

CONCLUSIONS

The use of new diagnostic tools, such as CBCT imaging, may provide detailed high-resolution images of oral structures, which help to make an initial diagnostic hypothesis and to plan surgery. Histopathology is mandatory for the differential diagnosis.

Alterações dimensionais do côndilo mandibular em indivíduos de 3 a 20 anos de idade usando tomografia computadorizada de feixe cônico: um estudo preliminar

INTRODUÇÃO: o exame de tomografia computadorizada de feixe cônico (TCFC) oferece excelente representação dos tecidos duros da articulação temporomandibular (ATM). OBJETIVO: investigar as alterações morfológicas do côndilo mandibular, da infância à idade adulta, utilizando a TCFC. MÉTODOS: um estudo transversal foi conduzido envolvendo 36 côndilos de 18 indivíduos com idades variando entre 3 e 20 anos. As imagens dos côndilos foram obtidas por meio do sistema i-CAT e medidas com uma ferramenta do programa específica para ATM, que permite cortes perpendiculares à cabeça do côndilo, com correção individual em função das diferenças angulares de cada um. As maiores distâncias nas vistas lateral e frontal foram consideradas tanto para os côndilos do lado direto como para os do lado esquerdo. RESULTADOS: a dimensão lateral do côndilo mandibular parece ser estabelecida de maneira precoce, sofrendo poucas alterações com o passar dos anos, enquanto a dimensão frontal tende a aumentar. Assimetrias entre o côndilo esquerdo e o direito foram comumente observadas; no entanto, tais diferenças não apresentaram significância estatística para as vistas lateral (P=0,815) e frontal (P=0,374). CONCLUSÕES: os côndilos apresentaram simetria com relação ao tamanho, sendo observado crescimento apenas na dimensão frontal Os resultados sugerem que a TCFC constitui-se numa ferramenta útil na mensuração e avaliação das dimensões condilares.

Medidas lineares dos estágios de desenvolvimento da dentição permanente humana usando Tomografia Computadorizada de Feixe Cônico: um estudo preliminar

OBJETIVO: determinar as medidas lineares dos estágios de desenvolvimento da dentição permanente humana, usando tomografia computadorizada de feixe cônico (TCFC). MÉTODOS: este estudo foi desenvolvido a partir de bancos de dados de clínicas radiológicas privadas, envolvendo 18 pacientes (13 do sexo masculino, 5 do sexo feminino, com idades variando entre 3 e 20 anos). As imagens das TCFC foram obtidas por meio do sistema i-CAT e medidas com uma função específica do programa desse mesmo sistema. Duzentos e trinta e oito dentes foram analisados, em diferentes estágios de desenvolvimento, nos planos coronal e sagital. O método foi baseado na delimitação e mensuração das distâncias entre pontos anatômicos correspondentes ao desenvolvimento das coroas e raízes dentárias. A partir dos valores obtidos, pôde-se desenvolver um modelo quantitativo para se avaliar os estágios inicial e final de desenvolvimento para todos os grupos dentários. RESULTADOS E CONCLUSÕES: as medidas obtidas dos diferentes grupos dentários estão de acordo com as estimativas das investigações publicadas previamente. As imagens por TCFC dos diferentes estágios de desenvolvimento podem contribuir no diagnóstico, planejamento e resultado dos tratamentos em diversas especialidades odontológicas. As dimensões das coroas e das raízes dentárias podem ter importantes aplicações clínicas e em pesquisas, constituindo uma técnica não invasiva que contribui com estudos in vivo. Entretanto, mais estudos são recomendados a fim de minimizar possíveis variáveis metodológicas.

Influence of intracanal post on apical periodontitis identified by cone-beam computed tomography

The determination of the success of endodontic treatment has been often discussed based on outcome obtained by periapical radiography. The aim of this study was to verify the influence of intracanal post on apical periodontitis detected by cone-beam computed tomography (CBCT). A consecutive sample of 1020 images (periapical radiographs and CBCT scans) taken from 619 patients (245 men; mean age, 50.1 years) between February 2008 and September 2009 were used in this study. Presence and intracanal post length (short, medium and long) were associated with apical periodontitis (AP). Chi-square test was used for statistical analyses. Significance level was set at p<0.01. The kappa value was used to assess examiner variability. From a total of 591 intracanal posts, AP was observed in 15.06%, 18.78% and 7.95% using periapical radiographs, into the different lengths, short, medium and long, respectively (p=0.466). Considering the same posts length it was verified AP in 24.20%, 26.40% and 11.84% observed by CBCT scans, respectively (p=0.154). From a total of 1,020 teeth used in this study, AP was detected in 397 (38.92%) by periapical radiography and in 614 (60.19%) by CBCT scans (p<0.001). The distribution of intracanal posts in different dental groups showed higher prevalence in maxillary anterior teeth (54.79%). Intracanal posts lengths did not influenced AP. AP was detected more frequently when CBCT method was used.

A new periapical index based on cone beam computed tomography

The purpose of this study was to evaluate a new periapical index based on cone beam computed tomography (CBCT) for identification of apical periodontitis (AP). The periapical index proposed in this study (CBCTPAI) was developed on the basis of criteria established from measurements corresponding to periapical radiolucency interpreted on CBCT scans. Radiolucent images suggestive of periapical lesions were measured by using the working tools of Planimp software on CBCT scans in 3 dimensions: buccopalatal, mesiodistal, and diagonal. The CBCTPAI was determined by the largest lesion extension. A 6-point (0-5) scoring system was used with 2 additional variables, expansion of cortical bone and destruction of cortical bone. A total of 1014 images (periapical radiographs and CBCT scans) originally taken from 596 patients were evaluated by 3 observers by using the CBCTPAI criteria. AP was identified in 39.5% and 60.9% of cases by radiography and CBCT, respectively (P < .01). The CBCTPAI offers an accurate diagnostic method for use with high-resolution images, which can reduce the incidence of false-negative diagnosis, minimize observer interference, and increase the reliability of epidemiologic studies, especially those referring to AP prevalence and severity.

Accuracy of cone beam computed tomography and panoramic and periapical radiography for detection of apical periodontitis

The aim of this study was to evaluate the accuracy of imaging methods for detection of apical periodontitis (AP). Imaging records from a consecutive sample of 888 imaging exams of patients with endodontic infection (1508 teeth), including cone beam computed tomography (CBCT) and panoramic and periapical radiographs, were selected. Sensitivity, specificity, predictive values, and accuracy of periapical and panoramic radiographs were calculated. Receiver operating characteristic (ROC) analysis was performed to assess the diagnostic accuracy of the panoramic and periapical images. Prevalence of AP was significantly higher with CBCT. Overall sensitivity was 0.55 and 0.28 for periapical and panoramic radiographs, respectively. ROC curves and area under curve (AUC) with periapical radiography showed a high accuracy for the cutoff value of 5 for both periapical (AUC, 0.90) and panoramic (AUC, 0.84) radiographs. AP was correctly identified with conventional methods when showed advanced status. CBCT was proved to be accurate to identify AP.

Method for determination of root curvature radius using cone-beam computed tomography images

This article describes and discusses a method to determine root curvature radius by using cone-beam computed tomography (CBCT). The severity of root canal curvature is essential to select instrument and instrumentation technique. The diagnosis and planning of root canal treatment have traditionally been made based on periapical radiography. However, the higher accuracy of CBCT images to identify anatomic and pathologic alterations compared to panoramic and periapical radiographs has been shown to reduce the incidence of false-negative results. In high-resolution images, the measurement of root curvature radius can be obtained by circumcenter. Based on 3 mathematical points determined with the working tools of Planimp® software, it is possible to calculate root curvature radius in both apical and coronal directions. The CBCT-aided method for determination of root curvature radius presented in this article is easy to perform, reproducible and allows a more reliable and predictable endodontic planning, which reflects directly on a more efficacious preparation of curved root canals.

Prevalence of endodontically treated teeth in a Brazilian adult population

This cross-sectional study examined the prevalence of endodontically treated teeth in 1,401 Brazilian adults. Panoramic radiographs were selected at the Radiological Center of Orofacial Images (CRIOF, Cuiabá, MT, Brazil) between August 2002 and September 2007. Three independent endodontists discussed interpretation criteria and classified specimens according to the following data: presence of root canal treatment, which was defined as partially or completely filled canal space, regardless of whether filling ended at the radiographic apex or not; presence of intracanal post; and associated apical periodontitis. Odds ratio, logistic regression and a chi-square test were used for statistical analyses. Significance level was set at p<0.05. Of 29,467 teeth evaluated, 6,313 (21.4%) were treated endodontically. Endodontic treatment was most frequent in maxillary premolars and molars, whereas mandibular incisors showed the lowest prevalence. Most endodontically treated teeth were found in people aged 46 to 60 years (47.6%, p<0.001) and the prevalence increased with age in this age range. Females (61.9%, p<0.001) showed a higher prevalence of teeth with root fillings than males. The present study found a higher prevalence of endodontically treated teeth in a Brazilian adult population compared to the prevalence reported in epidemiological studies conducted in other countries.

Cholestasis-induced fibrosis is reduced by interferon alpha-2a and is associated with elevated liver metalloprotease activity

BACKGROUND/AIM

Several drugs have been tested for the treatment of hepatic cirrhosis induced by various etiologic agents. Although interferon (IFN)alpha-2a has mostly been used to treat viral hepatitis, its anti-fibrogenic properties remain to be established.

METHODS

An experimental model of cholestasis-induced cirrhosis was used to test the effect of IFNalpha-2a. Cirrhosis was induced in rats via ligation of the common bile duct. IFNalpha-2a (100,000 IU/rat, s.c.) was administered daily throughout the experiment. Collagens and TIMP-1 mRNA transcripts were determined by semi-quantitative reverse transcriptase-polymerase chain reaction in liver tissue samples. Activity of metalloproteases (MMPs) was measured using gelatin (denatured collagen) as substrate and the specific size of the enzymes was estimated by zymograms. Histology was performed using Sirius red as a specific stain for collagenous material, and computer-assisted morphometric analyses were carried out. A polyclonal mouse anti-plasminogen activator inhibitor (PAI-1) antibody was used to evaluate the distribution during treatment with IFNalpha-2a.

RESULTS/CONCLUSIONS

MMP-activity was up-regulated in bile duct ligated rats treated with IFNalpha-2a. MMP-activity in homogenates of total liver was minimal as compared with activity in non-parenchymal cells isolated from the same parental perfused liver, indicating a cryptic MMP activity which was completely abolished by EDTA and 1,10 phenanthroline. Three bands of gelatin degradation were detected by zymography, corresponding to 95, 75 and 65 kDa. IFNalpha-2a decreased PAI-1 immunoreactivity in liver tissue slices as well as biochemical activity in non-parenchymal cell extracts (3.3+/-0.08 vs 7.4+/-1.1 U/mg protein). Procollagen alpha1 (III) and alpha1 (IV) genes expression were also down-regulated 1.5 and 4-fold, respectively. Interestingly, TIMP-1 gene expression did not change. Functional hepatic tests: alanine aminotransferase, aspartate aminotransferase, bilirubins and alkaline phosphatase were significantly lower in IFNalpha-2a treated animals. Analysis of histology demonstrated that IFNalpha-2a promoted resolution of fibrosis and decreased bile duct proliferation.

The genome sequence of the plant pathogen Xylella fastidiosa. The Xylella fastidiosa Consortium of the Organization for Nucleotide Sequencing and Analysis

Xylella fastidiosa is a fastidious, xylem-limited bacterium that causes a range of economically important plant diseases. Here we report the complete genome sequence of X. fastidiosa clone 9a5c, which causes citrus variegated chlorosis--a serious disease of orange trees. The genome comprises a 52.7% GC-rich 2,679,305-base-pair (bp) circular chromosome and two plasmids of 51,158 bp and 1,285 bp. We can assign putative functions to 47% of the 2,904 predicted coding regions. Efficient metabolic functions are predicted, with sugars as the principal energy and carbon source, supporting existence in the nutrient-poor xylem sap. The mechanisms associated with pathogenicity and virulence involve toxins, antibiotics and ion sequestration systems, as well as bacterium-bacterium and bacterium-host interactions mediated by a range of proteins. Orthologues of some of these proteins have only been identified in animal and human pathogens; their presence in X. fastidiosa indicates that the molecular basis for bacterial pathogenicity is both conserved and independent of host. At least 83 genes are bacteriophage-derived and include virulence-associated genes from other bacteria, providing direct evidence of phage-mediated horizontal gene transfer.

[Preliminary study of the relationship between the cardiopulmonary arrest time and its consequences in trauma patients]

The proposal of this research was to obtain parameters to start or maintain cardiopulmonary resuscitation (CPR) in victims of trauma. The duration of the cardiac arrest and the CPR of the survivors was described, as well as the cerebral performance and the mortality of these victims 24, 48 and 72 hours after these events had happened. With the results of this characterization the relation between duration of cardiac arrest time, CPR and mortality were described. Data for this report were collected in Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo emergency department. A big amount of the victims (93.4%) presents severe trauma and main cause of death was brain injury. Survival at 72 hours after CPR was 10%. The assessment, during the 72 hour period, of the survivors from cardiac arrest of traumatic cause has shown bad cerebral performance of those victims in that period of time. The survivor after the first episode of CPR was strongly related to cardiac arrest time when compared with CPR time. The time of cardiac arrest < or = 4 minutes and CPR < or = 20 minutes was related to survival more than 72 hours.

A common missense mutation in the adhalin gene in three unrelated Brazilian families with a relatively mild form of autosomal recessive limb-girdle muscular dystrophy

Autosomal recessive limb-girdle muscular dystrophies (AR LGMD) represent a heterogeneous group of diseases with a wide spectrum of clinical variability, classified phenotypically into two main groups, the most severe forms (Duchenne-like muscular dystrophy, DLMD, or severe childhood autosomal recessive muscular dystrophy, SCARMD) and the milder forms. Four genes causing AR LGMD have been mapped: the 15q (LGMD2a), the 2p (LGMD2b), the 13q locus (LGMD2c) and the adhalin gene on chromosome 17q (LGMD2d). In the present report we have performed linkage analysis with 17q markers in three mild AR LGMD and in four DLMD families with adhalin deficiency and unlinked to 2p, 15q or 13q genes. Linkage was observed only among the mild cases. Patients from these three 17q-linked families showed near or total deficiency of adhalin in muscle biopsies. An identical missense mutation was identified in all three 17q-linked unrelated families. These results indicate that AR LGMD with a mild phenotype is caused by mutations in the adhalin gene. In addition, they demonstrate that there is at least one other locus for DLMD associated with adhalin deficiency.