Injectable semi rigid penile prosthesis: study in rabbits and future perspectives

BackgroundPenile prostheses are the third option in the treatment of erectile dysfunction, however, despite their proven effectiveness, the occurrence of infections, advanced age of patients and comorbidities are the main limiting factors for this treatment modality. In the continuous search for biointegrated, clinically durable and minimally invasive treatment options, a possible model of penile prosthesis was sought through the use of intracavernous bacterial cellulose (BC) gel, in an experimental model of orchiectomized rabbits.MethodsThirty adult New Zealand rabbits were equally distributed into three groups: BC; vehicle and control. Each group was then subdivided according to the follow-up time of 3 and 6 months. Bilateral orchiectomy was performed 3 weeks before injection in the BC and vehicle groups. Pachymetry measurements of the penile axis, diameter and length were performed in situ. Histomorphometry analyzes of the corpora cavernosa (CC), thickness of the tunica albuginea, cell density, collagen and elastic fibers post-injection were also performed, in addition to immunohistochemistry for newly formed vessels.ResultsThe implant of BC increased both the length and thickness of the penis three and six months after the last injection, with a consequent increase in the diameter of the CC. On the other hand, the filling effect was not observed in the control and vehicle groups, confirming the degradation of this tissue after orchiectomy and the effectiveness of BC as a filling agent. Histomorphometry analyzes corroborate the mass effect of BC integrated into the tissue, permeated by predominantly lymphomononuclear inflammatory infiltrate, multinucleated giant foreign body cells, fibroblasts, elastic fibers and newly formed vessels, without degradation or loss of volume, even after six months of implantation.ConclusionsBiocompatibility and biointegration to the host tissue make BC a prosperous penile filling material, with local application and minimally invasive.     

Diagnosis of vertical root fracture in teeth close and distant to implant: an in vitro study to assess the influence of artifacts produced in cone beam computed tomography

Objectives

To evaluate the influence of artifacts produced by zirconium implant on the diagnosis of vertical root fracture (VRF) in teeth close and distant to the implant in cone beam computed tomography (CBCT) images. We also determined if kilovoltage (kVp) and metal artifact reduction (MAR) tool could influence this diagnosis.

Materials and methods

Twenty single-root teeth were divided in control and fractured groups (n = 10). The teeth were randomly positioned in the first and second and right and left pre-molar alveoli of a dry human mandible. CBCT exams were acquired using a ProMax 3D unit with varying kVp (70, 80, or 90 kVp), with or without MAR, and with and without a zirconium implant placed in the alveolus of first right molar. The images were evaluated by five observers. The area under the receiver operating characteristic curve (ROC), sensitivity, and specificity were calculated and compared by analysis of variance with a significance level of 5%.

Results

In general, ROC and sensitivity were not affected by the factors studied (p > 0.05). The main effects occurred in specificity; when implant was used without MAR, the values were lower for tooth 45 for all kVps (p = 0.0001).

Conclusions

Artifacts produced in the vicinity of teeth with suspected VRF impair the diagnosis by decreasing the specificity, because they can mimic the VRF line generating false positives. However, MAR improves the specificity, being its use recommended when metallic objects are present near teeth with suspected VRF.

Clinical Relevance

Since nowadays, many patients who undergo CBCT show implants and they definitively produce artifacts, it is important to evaluate the influence of such artifacts in the diagnosis of teeth that are close to the generator-artifact object.

     

Is there an association between overweight/obesity and dental implant complications? A systematic review and meta-analysis

The aim of this systematic review was to test the following hypotheses: (1) that there is no difference in implant survival rate between individuals with overweight or obesity and those who are within the ideal weight range; (2) that there are no differences between these groups regarding indicators of peri-implant health. Two independent reviewers performed a literature search of the PubMed/MEDLINE, Scopus, and Cochrane Library databases for studies published up to April 1, 2018. A meta-analysis was performed to determine the risk difference for implant failure and mean difference for marginal bone loss, probing depth, and bleeding on probing. Six studies were selected for review, involving a total of 746 patients with 986 implants: 609 in overweight or obese individuals and 377 in individuals within the ideal weight range. The findings of this systematic review indicate that the first hypothesis should be accepted, since no statistically significant difference in implant survival rate was found between individuals with overweight/obesity and those within the ideal weight range (P = 0.64). The second hypothesis was rejected, as the review indicated a difference in marginal bone loss (P < 0.00001), probing depth (P < 0.00001), and bleeding around dental implants (P < 0.00001).     

Primary tumor cells of myeloma patients induce interleukin-6 secretion in long-term bone marrow cultures

Long-term bone marrow cultures (LTBMC) from patients with multiple myeloma (MM) and normal donors were analyzed for immunophenotype and cytokine production. Both LTBMC adherent cells from myeloma and normal donor origin expressed CD10, CD13, the adhesion molecules CD44, CD54, vascular cell adhesion molecule 1, very late antigen 2 (VLA-2), and VLA- 5, and were positive for extracellular matrix components fibronectin, laminin, and collagen types 3 and 4. LTBMC from myeloma patients and normal donors spontaneously secreted interleukin-6 (IL-6). However, levels of IL-6 correlated with the stage of disease; highest levels of IL-6 were found in LTBMC from patients with active myeloma. To identify the origin of IL-6 production, LTBMC from MM patients and normal donors were cocultured with BM-derived myeloma cells and cells from myeloma cell lines. IL-6 was induced by plasma cell lines that adhered to LTBMC such as ARH-77 and RPMI-8226, but not by nonadhering cell lines U266 and FRAVEL. Myeloma cells strongly stimulated IL-6 secretion in cocultures with LTBMC adherent cells from normal donors and myeloma patients. When direct cellular contact between LTBMC and plasma cells was prevented by tissue-culture inserts, no IL-6 production was induced. This implies that intimate cell-cell contact is a prerequisite for IL-6 induction. Binding of purified myeloma cells to LTBMC adherent cells was partly inhibited by monoclonal antibodies against adhesion molecules VLA-4, CD44, and lymphocyte function-associated antigen 1 (LFA-1) present on the plasma cell. Antibodies against VLA-4, CD29, and LFA-1 also inhibited the induced IL-6 secretion in plasma cell-LTBMC cocultures. In situ hybridization studies performed before and after coculture with plasma cells indicated that LTBMC adherent cells produce the IL-6. These results suggest that the high levels of IL-6 found in LTBMC of MM patients with active disease are a reflection of their previous contact with tumor cells in vivo. These results provide a new perspective on tumor growth in MM and emphasize the importance of plasma cell-LTBMC interaction in the pathophysiology of MM.     

A placebo-controlled double-blind randomized study of venlafaxine in the treatment of depression in dementia

BACKGROUND/AIMS: To evaluate the efficacy and safety of venlafaxine in the treatment of major depression in dementia. METHODS: Thirty-one outpatients who had dementia and major depression participated in this randomized, double-blind, placebo-controlled, 6-week, flexible dose clinical trial. The screening measures were Cornell Scale for depression in dementia, DSM-IV for depression and dementia and Mini-Mental State Examination. The outcome measures were response rate, Montgomery-Asberg Depression Rating scale and Clinical Global Impressions. RESULTS: The percentage of patients defined as Montgomery-Asberg Depression Rating scale responders was approximately the same in the placebo and in the venlafaxine groups. Clinical Global Impressions showed no significant difference between the groups. The reasons for dropouts show borderline significance between the two groups. There was no statistically significant difference in the incidence of adverse events between the venlafaxine and placebo-treated groups. CONCLUSIONS: Our data do not support the hypothesis that venlafaxine improves mood in elderly demented patients.     

Lobar brain hemorrhages and white matter changes: Clinical, radiological and laboratorial profiles

BACKGROUND: White matter changes have several histopathologic correlates including cerebral amyloid angiopathy (CAA). The aim of this study was to characterize the clinical, laboratorial and neuroradiological profile of a CAA-related lobar hemorrhages case series. METHODS: A cohort of 50 consecutive patients with cerebral lobar hemorrhages was studied and clinical, radiological data and ApoE polymorphisms were analyzed. White matter changes were graded and microbleeds were characterized according to number and location using T2* MRI. RESULTS: A statistically significant association was found between the prestroke cognitive performance and poststroke dementia and between hemorrhage volume and mortality. More severe white matter changes were found in probable CAA when comparing to possible CAA. The most prominent white matter lesions are associated with the presence and the number of microbleeds. The frequency of APOE epsilon 2 and epsilon 4 alleles was higher in this cohort when compared to a Northern Portuguese population. CONCLUSION: White matter changes are frequent in lobar hemorrhage patients and are associated with cortical microbleeds, the radiological hallmark of CAA. Therefore, white matter changes may be the sole phenotype of CAA and, potentially, involved in the pre-stroke cognitive impairment presented by the patients, which are genetically distinct from the population in general.