Percutaneous Transatrial Access to the Pericardial Space for Epicardial Mapping and Ablation

Background-Puncture of the atrial appendage may provide access to the pericardial space. The aim of this study was to evaluate the feasibility of epicardial mapping and ablation through an endocardial transatrial access in a swine model. Methods and Results-An 8-F Mullins sheath was used to perforate the right (n=16) or left (n=1) atrial appendage in 17 pigs (median weight, 27.5 kg; first and third quartiles [Q1, Q3], 25.2, 30.0 kg). A 7-F ablation catheter was introduced into the pericardial space to perform epicardial mapping and deliver radiofrequency pulses on the atria. The pericardial space was entered in all 17 animals. In 15 (88%) animals, there was no hemodynamic instability (mean blood pressure monitoring, initial median, 80 mm Hg; Q1, Q3, 70, 86 mm Hg; final median, 88 mm Hg; Q1, Q3, 80, 96 mm Hg; P=0.426). In these 15, a mild hemorrhagic pericardial effusion was identified and aspirated (median, 20 mL; Q1, Q3, 15, 30 mL) during the procedure, and postmortem gross analysis revealed that the atrial perforation was closed in these animals. In 2 (12%) of the 17 animals, there was major pericardial bleeding with hemodynamic collapse. On gross examination, it was found that pericardial space was accessed through right ventricular perforation in 1 animal and the tricuspid annulus in the other. After the initial study, we used an occlusion device in 3 other animals to attempt to seal the puncture (2 at the right atrial appendage and 1 at the right ventricle). These 3 animals had no significant pericardial bleeding. Conclusions-Transatrial endovascular right atrial appendage puncture may provide a potential alternative route for pericardial access. Further studies are needed to evaluate its safety with longer and more-complex procedures before being applied in clinical settings. (Circ Arrhythm Electrophysiol. 2011;4:331-336.)

Genotoxic effect of Physalis angulata L. (Solanaceae) extract on human lymphocytes treated in vitro

Physalis angulata L (Solanaceae) is a medicinal plant from North of Brazil, whose different extracts and infusions are commonly used in the popular medicine for the treatment of malaria, asthma, hepatitis, dermatitis and rheumatism. However, the genotoxic effects of P. angulata on human cells is not well known. The main purpose of the present study was to evaluate the in vitro genotoxic effects of aqueous extract of P angulata using the comet assay and the micronucleus assay in human lymphocytes provided from 6 healthy donors. Treatments with P angulata extracts were performed in vitro in order to access the extent of DNA damage. The comet assay has shown that treatments with P angulata at 0.5, 1.0, 2.0, 3.0 and 6.0 mu g/mL in Culture medium were genotoxic. Lymphocytes treated with P angulata at the concentrations of 3.0 and 6.0 mu g/mL in culture medium showed a statistically significant increase in the frequency of micronucleus (p<0.05), however, the cytokinesis blocked proliferation index (CBPI) was not decreased after P angulata treatment. In conclusion, the present work demonstrated the genotoxic effects of P angulata extract on human lymphocytes in vitro.

Frequency of insertion/deletion polymorphism in exon 8 of HLA-G and kidney allograft outcome

Human leukocyte antigen-G (HLA-G) is a non-classical major histocompatibility complex (MHC) class Ib molecule predominantly expressed in cytotrophoblasts, where it acts as a specific immunosuppressor. Literature data have shown that grafts in some settings, such as cardiac and liver/kidney-associated transplantations, express HLA-G and this expression is associated with less severe rejection and also reduces the incidence of rejection. Fourteen-base pair deletion/insertion polymorphism has been reported in exon 8 of the 3`-untranslated region of HLA-G. This polymorphism within exon 8 of the HLA-G gene might influence transcription activity, which in turn may influence the stability of HLA-G transcripts. This influences the stability of the HLA-G protein and therefore is of potential functional relevance. In order to determine a possible correlation between the 14-bp insertion/deletion polymorphism and kidney allograft outcome, we isolated genomic DNA from 83 patients who had received isolated kidney allografts, and we classified the 83 specimens into two groups, grafts presenting Banff features of rejection group and a non-rejection group, and compared them with a control group of 97 healthy subjects. The 14-bp polymorphism at exon 8 was genotyped in all groups. There was no significant difference in allelic frequencies of 14-bp insertion/deletion polymorphism between normal controls and kidney transplant patients. In the RG, the homozygous genotype +14/+14 bp (P = 0.0238) was significantly increased in the group with acute rejection compared with the healthy control group. Analysis of other HLA-G polymorphisms and functional studies on immune regulation are essential to elucidate the role of HLA-G in kidney allografts.

Bupivacaine 0.25% and methylene blue spread with epidural anesthesia in dog

Objective To evaluate the extent sensory and motor blocks produced by the epidural injection of different volumes of 0.25% bupivacaine (Bu) with methylene blue (MB), in dogs. Study design Prospective experimental trial. Animals Twenty healthy adult mongrel dogs, weighing 9.9 +/- 1.9 kg. Methods Dogs were randomly allocated into one of four groups that received 0.2, 0.4, 0.6 or 0.8 mL kg-1 of an epidural solution containing 0.25% Bu and MB. Sensory block was evaluated against time by pinching the tail, hind limb interdigital web, toenail bases and the skin over the vertebral dermatomes. Motor block was assessed by ataxia, hind limb weight-bearing ability and by loss of muscle tone of the tail and pelvic limbs. Data were collected at 2, 5, 10, 15 and 30 minutes after the end of epidural injection. After the final time point, dogs were euthanatized and laminectomies were conducted to expose the extent of the dural dye staining. Results The volumes 0.2, 0.4, 0.6 and 0.8 mL kg-1 of 0.25% Bu and MB blocked a mean of 5, 14.2, 20.2 and 21 dermatomes, respectively. The extent of the senory block increased up to a volume of 0.6 mL kg-1. Motor block was longer-lasting and more intense than sensory block. Complete dyeing of the spinal cord with MB was achieved in some dogs at 0.4 mL kg-1 and all dogs at 0.6 mL kg-1. Conclusions The volume of anesthetic injected into the epidural space plays an important role in the quality of the epidural anesthesia. At 0.25%, bupivacaine provided an efficient sensory block at 0.6 mL kg-1. Clinical relevance Relatively high volumes (0.6 mL kg-1) of 0.25%, BU and MB were needed to produce an effective sensory and motor block caudal to the umbilicus, but all spinal cord segments were reached by MB at this dose.

A Novel Approach to Intraoral Mandibular Nerve Anesthesia: Changing Reference Planes in the Gow-Gates Block Technique

Purpose: The Gow-Gates technique is said to have several advantages over traditional techniques to achieve mandibular nerve anesthesia; however, its routine use is quite limited, mainly due to complications during visual alignment of reference landmarks. The purpose of this study was to verify the validity and accuracy of a new method to reach the injection site. Material and Methods: Fifteen magnetic resonance images were captured. Distances from the ideal injection point in the condylar neck (puncture ideal) to the injection points located in the a and 0 plane intersection (Puncture Gow-Gates and puncture modified) were measured and compared. Results: Positive and significant (P <= .003) Pearson correlations between landmarks and injection points confirmed the validity of the modified technique. Paired t test showed that the segment line puncture ideal-puncture modified, 5.17 mm, was 3 times shorter (P < .001) than the segment line puncture ideal-puncture Gow-Gates, 17.91 mm. As calculated by linear regression, establishing the injection point of the modified technique depended only on the anteroposterior and lateromedial condyle positions. Conclusions: The modified technique proved to be valid and precise and has a determined and an effective injection site. (C) 2009 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 67:2609-2616, 2009

Patients with oral squamous cell carcinoma are characterized by increased frequency of suppressive regulatory T cells in the blood and tumor microenvironment

Oral squamous cell carcinoma (OSCC) is a cancerous lesion with high incidence worldwide. The immunoregulatory events leading to OSCC persistence remain to be elucidated. Our hypothesis is that regulatory T cells (Tregs) are important to obstruct antitumor immune responses in patients with OSCC. In the present study, we investigated the frequency, phenotype, and activity of Tregs from blood and lesions of patients with OSCC. Our data showed that > 80% of CD4(+)CD25(+) T cells isolated from PBMC and tumor sites express FoxP3. Also, these cells express surface Treg markers, such as GITR, CD45RO, CD69, LAP, CTLA-4, CCR4, and IL-10. Purified CD4(+)CD25(+) T cells exhibited stronger suppressive activity inhibiting allogeneic T-cell proliferation and IFN-gamma production when compared with CD4(+)CD25(+) T cells isolated from healthy individuals. Interestingly, approximately 25% of CD4(+)CD25(-) T cells of PBMC from patients also expressed FoxP3 and, although these cells weakly suppress allogeneic T cells proliferative response, they inhibited IFN-gamma and induced IL-10 and TGF-beta secretion in these co-cultures. Thus, our data show that Treg cells are present in OSCC lesions and PBMC, and these cells appear to suppress immune responses both systemically and in the tumor microenvironment.

Bone repair and augmentation using block of sintered bovine-derived anorganic bone graft in cranial bone defect model

To histomorphometrically investigate the repair of critical size defects (CSDs) and bone augmentation in cranial walls using block of sintered bovine-derived anorganic bone (sBDAB) graft. Forty guinea-pigs were divided into test (n=20) and CSD control (n=20) groups. In each animal, a full-thickness bone defect with 9.5 mm diameter was made in the frontal bone. The defects were filled with an sBDAB block soaked in blood in the test group and with blood clot in the CSD control group. The skulls were collected at 0 h (n=2) and 30, 90 and 180 days (n=6/group and period) postoperatively. The volume density and total volume of newly formed bone, sBDAB, blood vessels and connective tissue, vertical thickness of removed bone plug, sBDAB block and graft area were evaluated. The vertical thickness of the adapted sBDAB block was 3.8 times higher than that of the removed bone plug and did not show significant difference between periods, filling in average 29.8% of the total graft region. The sBDAB block exhibited complete osseointegration with the borders of the defect at 90 days. At 90 and 180 days, the vertical thickness of the graft was 279% in the average, and the total volume of bone augmentation was, respectively, 78.8% and 148.5% higher compared with the removed bone plug. The defects of the CDS control group showed limited osteogenesis and filling by connective tissue plus tegument. The sBDAB block can be used to promote repair of CSDs and bone augmentation in the craniomaxillofacial region, due to its good osteoconductive and slow resorptive properties. To cite this article:Cestari TM, Granjeiro JM, de Assis GF, Garlet GP, Taga R. Bone repair and augmentation using block of sintered bovine-derived anorganic bone graft in cranial bone defect model.Clin. Oral Impl. Res. 20, 2009; 340-350.doi: 10.1111/j.1600-0501.2008.01659.x.

Influence of nicotine on healing process of autogenous bone block grafts in the mandible: A histomorphometric study in rats

Purpose: The aim of this study was to perform qualitative and quantitative analyses of the effect of nicotine on autogenous bone block grafts and to describe events in the initial healing phase and the differences in the repair processes between animals exposed to nicotine and controls. Materials and Methods: Forty-eight female Wistar rats were randomly divided into 2 groups, the nicotine group and the saline group. All animals received either nicotine (3 mg/kg) or saline 4 weeks before the surgical procedure and continued to receive nicotine from surgery to sacrifice at 7, 14, or 28 days. The autogenous bone block graft was harvested from the calvaria and stabilized on the external cortical area near the angle of the mandible. Results: The histologic analyses of the nicotine group depicted a delay in osteogenic activity at the bed-graft interface, as well as impairment of the organization of the granulation tissue that developed instead of blood clot. Nicotine-group specimens exhibited less bone neoformation, and the newly formed bone was poorly cellularized and vascularized. The histometric analysis revealed significantly less bone formation in the nicotine group at both 14 days (23.75% +/- 6.18% versus 51.31% +/- 8.31%) and 28 days (42.44% +/- 8.70% versus 73.00% +/- 4.99%). Conclusion: Nicotine did jeopardize the early healing process of autogenous bone block grafts in rats but did not prevent it.

Influence of Orthognathic Surgery on Voice Fundamental Frequency

Considering that orthognathic surgery promotes changes in orofacial structures constituting the resonating system, functional changes secondary to surgery are expected to affect speech, leading to the need for further speech and voice adjustments. Thus, understanding the possible relationships of these structures with voice production is important. Therefore, this Study aimed to describe the changes in voice fundamental frequency of a patient submitted to orthognathic surgery and observe if there is a relationship with hyoid bone positioning at the different treatment periods. The results revealed that voice fundamental frequency increased after surgery, returning to values close to the preoperative condition, which corresponded to vertical movement of the hyoid bone.

Anesthetic efficacy of inferior alveolar nerve block plus buccal infiltration or periodontal ligament injections with articaine in patients with irreversible pulpitis in the mandibular first molar

Objective. We compared the anesthetic efficacy of inferior alveolar nerve block (IANB) plus buccal infiltration (BI) and IANB plus periodontal ligament (PDL) articaine injections in patients with irreversible pulpitis in the mandibular first molar. Study design. Fifty-seven volunteers, patients with irreversible pulpitis in the mandibular first molar admitted to the Department of Stomatology, Second Affiliated Hospital, Sun Yat-Sen University, randomly received conventional IANB, containing 1.7 mL 4% articaine/HCl with 1:100,000 epinephrine, plus either BI or PDL injections containing 0.4 mL articaine/HCl with 1: 100,000 epinephrine. The patients recorded the pain of the injections and endodontic access on a Heft-Parker visual analog scale (VAS). Results. According to the VAS scores, all patients experienced no or mild pain with BI and PDL injections after the application of IANB. Anesthetic success occurred in 81.48% for IANB plus BI (IANB/BI) compared with 83.33% for IANB plus PDL injection (IANB/PDL injection). None of the observed differences between the 2 groups was significant (P > .05). Conclusion. Both injection combinations resulted in high anesthetic success in patients with irreversible pulpitis in the mandibular first molar. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009;108:e89-e93)

Resin cement thickness in oval-shaped canals: Oval vs. circular fiber posts in combination with different tips/drills for post space preparation

Purpose: To evaluate the cement thickness around oval and circular posts luted in oval post spaces prepared with different drills/tips. Methods: Extracted premolars were endodontically treated and obturated, then randomly divided into three groups (n = 5) according to the tips/drills used for post-space preparation and to the type of fiber post luted: medium grit oval tip + oval posts, fine grit oval tip + oval posts, Mtwo Post File drill + circular posts. The specimens were sectioned in horizontal slices; one slice per canal third was chosen for each post-space, resulting in three slices for each specimen. The distances between the canal wall and the post perimeter were measured on SEM images of each slice. Results: The fine grit tip + oval post group obtained statistically significant lower cement thicknesses than the other groups (P < 0.05), in particular in the apical third. The MtwoPF + circular post group showed the highest cement thickness, comparable to that of the medium tip + oval post group. A good post fitting in oval-shaped canals can be obtained using a fine grit oval tip combined with oval posts. (Am J Dent 2009;22:290-294).