Accidental displacement and migration of endosseous implants into adjacent craniofacial structures: A review and update

Objectives: Accidental displacement of endosseous implants into the maxillary sinus is an unusual but potential complication in implantology procedures due to the special features of the posterior aspect of the maxillary bone; there is also a possibility of migration throughout the upper paranasal sinuses and adjacent structures. The aim of this paper is to review the published literature about accidental displacement and migration of dental implants into the maxillary sinus and other adjacent structures. Study Design: A review has been done based on a search in the main on-line medical databases looking for papers about migration of dental implants published in major oral surgery, periodontal, dental implant and ear-nose-throat journals, using the keywords “implant,” “migration,” “complication,” “foreign body” and “sinus.” Results: 24 articles showing displacement or migration to maxillary, ethmoid and sphenoid sinuses, orbit and cranial fossae, with different degrees of associated symptoms, were identified. Techniques found to solve these clinical issues include Cadwell-Luc approach, transoral endoscopy approach via canine fossae and transnasal functional endoscopy surgery. Conclusion: Before removing the foreign body, a correct diagnosis should be done in order to evaluate the functional status of the ostiomeatal complex and the degree of affectation of paranasal sinuses and other involved structures, determining the size and the exact location of the foreign body. After a complete diagnosis, an indicated procedure for every case would be decided. Key words:Implant, oral surgery, foreign body, paranasal sinuses, displacement, migration.     

Lubricin immunohistochemical expression in human temporomandibular joint disc with internal derangement

J Oral Pathol Med (2011) 40 : 587–592 Lubricin is a chondroprotective, mucinous glycoprotein which contribute to joint lubrication, especially to boundary lubrication and maintains joint integrity. The present investigation aimed to study the immunolocalization of lubricin in TMJ discs from patients affected by anterior disc displacement with reduction (ADDwR) ADDwoR. Eighteen TMJ displaced disc affected by ADDwoR were processed immunohistochemically, with a polyclonal anti‐lubricin antibody, used at 1:50 working dilution. The percentage of lubricin immunopositive cells (extent score = ES) and the extent of lubricin staining of the disc extracellular matrix (ECM), were evaluated. Each sample was scored for histopathological changes. Percentage of immunostained surface disc cells was the same (ES = 4) in both control and ADDwOR cells, being this data not statistically significant (P < 0.05). In pathological specimens the percentages of lubricin‐stained cells was very high with an ES of 4 respect to control specimen, and this difference was statistically significant different (P > 0.05). The extracellular matrix (ECM) of discs at the disc surfaces of both pathological and normal specimens was very heavily stained (++++). Both the ES and ECM staining were not statistically correlated to the TMJ degeneration score according to the Spearman’s rank correlation coefficient. According to our findings, a longstanding TMJ disc injury, affects lubricin expression in the TMJ disc tissue and not its surfaces, moreover, lubricin immunostaining is not correlated to TMJ disc histopathological changes.     

Hepatocyte xenotransplantation for treating liver disease

Bonavita AG, Quaresma K, Cotta‐de‐Almeida V, Alves Pinto M, Magalhães Saraiva R, Anastácio Alves L. Hepatocyte xenotransplantation for treating liver disease. Xenotransplantation 2010; 17: 181–187. © 2010 John Wiley & Sons A/S. Abstract: The treatment of acute and chronic liver failure is still a challenge despite modern therapeutic innovations. While liver transplantation can restore liver function and improve patient survival, donor shortages limit this treatment to a small number of patients. Cellular xenotransplantation has emerged as an alternative for treating liver failure. Xenohepatocytes could be readily available in sufficient quantities to treat patients in critical condition and thereby reduce the donor shortage. The use of isolated encapsulated or non‐encapsulated cells can reduce the immunorejection response. Several studies using animal models of acute or chronic liver failure have demonstrated improved survival and recovery of liver function after xenotransplantation of adult hepatocytes. Porcine liver cells are a potential source of xenohepatocytes due to similarities with human physiology and the great number of hepatocytes that can be obtained. The recent development of less immunogenic transgenic pigs, new immunosuppressive drugs, and cellular encapsulation systems represents important advances in the field of cellular xenotransplantation. In this study, we review the work carried out in animal models that deals with the advantages and limitations of hepatocyte xenotransplantation, and we propose new studies needed in this field.     

Neuroprotective effect of a CNTF-expressing lentiviral vector in the quinolinic acid rat model of Huntington's disease.

Neurodegenerative diseases represent promising targets for gene therapy approaches provided effective transfer vectors. In the present study, we evaluated the effectiveness of LacZ-expressing lentiviral vectors with two different internal promoters, the mouse phosphoglycerate kinase 1 (PGK) and cytomegalovirus (CMV), to infect striatal cells. The intrastriatal injection of lenti-beta-Gal vectors lead to 207, 400 +/- 11,500 and 303,100 +/- 4,300 infected cells in adult rats, respectively. Importantly, the beta-galactosidase activity was higher in striatal extracts from PGK-LacZ-injected animals as compared to CMV-LacZ animals. The efficacy of the system was further examined with a potential therapeutic gene for the treatment of Huntington's disease, the human ciliary neurotrophic factor (CNTF). PGK-LacZ- or PGK-CNTF-expressing viruses were stereotaxically injected into the striatum of rats, 3 weeks later the animals were unilaterally lesioned with 180 nmol of quinolinic acid (QA). Control animals displayed 148 +/- 43 apomorphine-induced rotations ipsilateral to the lesion 5 days postlesion as compared to 26 +/- 22 turns/45 min in the CNTF-treated group. The extent of the striatal damage was significantly diminished in the CNTF-treated rats as indicated by the 52 +/- 9.7% decrease of the lesion volume and the sparing of DARPP-32, ChAT and NADPH-d neuronal populations. These results further establish that lentiviruses may represent an efficient gene delivery system for the screening of therapeutic molecules in Huntington's disease.     

Haplotype analysis of VEGF gene polymorphisms in polycystic ovary syndrome

Abstract

This study evaluated the association of polymorphisms of VEGF (endothelial vascular growth factor) gene + 936C/T (rs3025039), 1154?G/A (rs 1570360) and ?2578?C/A (rs 699947) in patients with polycystic ovary syndrome (PCOS) and to perform the haplotypes formed by the alleles in the Brazilian population. A total of 110 women without PCOS and 112 women with PCOS were included in the study. Genotyping analyses were performed using the PCR-RFLP assays (rs 3025039 and rs 699947) and by allelic discrimination using the real-time PCR technique (rs 1570360). In the univariate analysis, we observed a significant difference between the groups for the polymorphism rs 1570360 and this polymorphism presented statistical differences between the groups for the recessive model (p?=?.04). The frequency of the T-G-C haplotype showed a statistically significant difference between women with PCOS and controls (p?=?.05). The ?2578?A/C polymorphism was more frequent in the control group, which may be associated with a protective characteristic for the PCOS manifestation. In the sample analysis, polymorphism rs 1570360 is associated with PCOS and the T-G-C haplotype could be associated with protective factors.     

Influence of indigenous microbiota on experimental toxoplasmosis in conventional and germ‐free mice

Toxoplasmosis represents one of the most common zoonoses worldwide. Its agent, Toxoplasma gondii, causes a severe innate pro‐inflammatory response. The indigenous intestinal microbiota promotes host animal homoeostasis and may protect the host against pathogens. Germ‐free (GF) animals provide an important tool for the study of interactions between host and microbiota. In this study, we assessed the role of indigenous microorganisms in disease development utilizing a murine toxoplasmosis model, which includes conventional (CV) and GF NIH Swiss mice. CV and GF mice orally inoculated with T. gondii had similar survival curves. However, disease developed differently in the two animal groups. In CV mice, intestinal permeability increased and levels of intestinal pro‐inflammatory cytokines were altered. In GF animals, there were discrete epithelial degenerative changes and mucosal oedema, but the liver and lungs displayed significant lesions. We conclude that, despite similar survival curves, CV animals succumb to an exaggerated inflammatory response, whereas GF mice fail to produce an adequate systemic response.     

Prevalence of sexually transmitted infections among HIV-infected women in Brazil

This study aimed to evaluate the prevalence of sexually transmitted infections (STIs) and associated risk factors in HIV-infected pregnant women followed for prenatal care in Salvador, Bahia. This was a cross-sectional study of 63 women seeking prenatal care at a reference center. Participants were interviewed regarding socio-epidemiological and clinical history, and were tested for HBsAg, anti-HCV, anti HTLV I/II, VDRL, Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma hominis, Ureaplasma urealyticum, CD4 count, and HIV plasma viral load. The main outcome variable was the presence of any STI. The mean age of patients was 28.2 years (16-40 years). 23 (36.5%) were diagnosed with at least one STI. The frequency of diagnoses was: HBV, 3.2%; HCV, 8.1%; HTLV I/II, 3.4%; syphilis, 9.5%; Chlamydia trachomatis, 11.1%; HPV, 15.0%; Mycoplasma hominis, 2.1%, and Ureaplasma urealyticum, 2.1%. No case of Neisseria gonorrhoeae was identified. No association was found between socio-epidemiological variables and the presence of an STI. CD4 T lymphocyte < 500 cells/μL (p = 0.047) and plasma viral load >1,000 copies (p = 0.027) were associated with the presence of STI. STIs are frequent in pregnant women infected with HIV, and all HIV-infected pregnant women should be screened to decrease transmission of these pathogens and to protect their own health.     

Cardiac dysfunction in rats prone to audiogenic epileptic seizures

PurposeCardiac dysfunction is one of the possible causes of sudden unexpected death in epilepsy (SUDEP). Therefore, the objective of this study was to evaluate cardiac and electrocardiographic parameters in rats with audiogenic epileptic seizures (WAR – Wistar audiogenic rats).MethodsIn vivo arterial pressure, heart rate (HR), autonomic tone and electrocardiography (ECG) were measured in awake animals in order to examine cardiac function and rhythm. Ex vivo, the Langendorff technique was used to analyze the cardiac function and the severity of reperfusion arrhythmias. In vitro, confocal microscopy was used to evaluate calcium transient parameters of isolated ventricular cardiomyocytes.ResultsIn vivo autonomic tone evaluation revealed enhanced sympathetic activity, changes in cardiac function with increased systolic arterial pressure and higher basal HR in WAR. In addition, ECG analysis demonstrated electrical alterations with prolongation of the QT interval and QRS complex in these animals. Ex vivo, we observed a decrease in systolic tone and HR and an increase in the duration of ischemia/reperfusion arrhythmias in WAR. Moreover, intracellular Ca²⁺ handling analysis revealed an increase in the peak of calcium and calcium transient decay in audiogenic rats. Treatment with atenolol (β1-adrenergic antagonist) normalized the systolic tone, reduced cardiac hypertrophy and the associated increase in the susceptibility to reperfusion arrhythmias observed in WAR.ConclusionWe present evidence that chronic disturbances in sympathetic tone in WAR cause increases the risk to life-threatening arrhythmias. Our results support a relationship between seizures, cardiac dysfunction and cardiac arrhythmias, which may contribute to the occurrence of SUDEP.