Compactibility study of calcium phosphate biomaterials

This study investigated the micromechanism responsible for the densification and consolidation of powders during dynamic compaction, an experimental process in which ceramic is formed without heating. Three calcium-deficient apatites (CDA: two powders and a fibrous compound) and a biphasic calcium phosphate (BCP) were studied to determine their aptitude (rheological and physical properties) for compactibility under various dynamic compaction pressures. Powders were investigated for their physicochemistry, particle size, and flow time, and compacts for their compaction rate, density, specific area, mechanical characteristics, and disintegration time. Powder particles showed different morphological features depending on the synthesis protocol used, specific area and rheological behaviour. Compacts were not obtained with BCP, regardless of the gas pressure used, whereas CDA produced compacts with good mechanical properties (high hardness and compression stress), particularly for the fibrous compound. The poor compressibility and compactibility of BCP powders were confirmed, whereas fibrous CDA powders showed good compactibility conducive to high-quality filling of biomaterials.     

Single-step transvenous extraction of a passive fixation lead with delayed perforation of the right ventricle

Delayed pacemaker lead perforation is a very rare complicationand most of the published reports involve active fixation leads.The authors report an uneventful transvenous extraction of apassive fixation lead, which had a delayed perforation of theright ventricle, disclosed two months after pacemaker implantation.     

Laparoendoscopic single‐site (LESS) vs laparoscopic living‐donor nephrectomy: a systematic review and meta‐analysis

The aim of this study was to provide a systematic review and meta‐analysis of reports comparing laparoendoscopic single‐site (LESS) living‐donor nephrectomy (LDN) vs standard laparoscopic LDN (LLDN). A systematic review of the literature was performed in September 2013 using PubMed, Scopus, Ovid and The Cochrane library databases. Article selection proceeded according to the search strategy based on Preferred Reporting Items for Systematic Reviews and Meta‐analyses criteria. Weighted mean differences (WMDs) were used to measure continuous variables and odds ratios (ORs) to measure categorical ones. Nine publications meeting eligibility criteria were identified, including 461 LESS LDN and 1006 LLDN cases. There were more left‐side cases in the LESS LDN group (96.5% vs 88.6%, P < 0.001). Meta‐analysis of extractable data showed that LLDN had a shorter operative time (WMD 15.06 min, 95% confidence interval [CI] 4.9–25.1; P = 0.003), without a significant difference in warm ischaemia time (WMD 0.41 min, 95% CI –0.02 to 0.84; P = 0.06). Estimated blood loss was lower for LESS LDN (WMD ?22.09 mL, 95% CI –29.5 to –14.6; P < 0.001); however, this difference was not clinically significant. There was a greater likelihood of conversion for LESS LDN (OR 13.21, 95% CI 4.65–37.53; P < 0.001). Hospital stay was similar (WMD –0.11 days, 95% CI –0.33 to 0.12; P = 0.35), as well as the visual analogue pain score at discharge (WMD –0.31, 95% CI –0.96 to 0.35; P = 0.36), but the analgesic requirement was lower for LESS LDN (WMD –2.58 mg, 95% CI –5.01 to –0.15; P = 0.04). Moreover, there was no difference in the postoperative complication rate (OR 1.00, 95% CI 0.65–1.54; P = 0.99). Renal function of the recipient, as based on creatinine levels at 1 month, showed similar outcomes between groups (WMD 0.10 mg/dL, –0.09 to 0.29; P = 0.29). In conclusion, LESS LDN represents an emerging option for living kidney donation. This procedure offers comparable surgical and early functional outcomes to the conventional LLDN, with a lower analgesic requirement. However, it is more technically challenging than LLDN, as shown by a greater likelihood of conversion. The role of LESS LDN remains to be defined.     

Robot-assisted Laparoscopic Adrenalectomy: Step-by-Step Technique and Comparative Outcomes

Background

Recent evidence supports the use of robotic surgery for the minimally invasive surgical management of adrenal masses.

Objective

To describe a contemporary step-by-step technique of robotic adrenalectomy (RA), to provide tips and tricks to help ensure a safe and effective implementation of the procedure, and to compare its outcomes with those of laparoscopic adrenalectomy (LA).

Design, setting, and participants

We retrospectively reviewed the medical charts of consecutive patients who underwent RA performed by a single surgeon between April 2010 and October 2013. LA cases performed by the same surgeon between January 2004 and May 2010 were considered the control group.

Surgical procedure

The main steps of our current surgical technique for RA are described in this video tutorial: patient positioning, port placement, and robot docking; exposure of the adrenal gland; identification and control of the adrenal vein; circumferential dissection of the adrenal gland; and specimen retrieval and closure.

Outcome measurements and statistical analysis

Demographic parameters and main surgical outcomes were assessed.

Results and limitations

A total of 76 cases (RA: 30; LA: 46) were included in the analysis. Median tumor size on computed tomography (CT) was significantly larger in the LA group (3 cm [interquartile range (IQR): 3] vs 4 cm [IQR: 3]; p = 0.002). A significantly lower median estimated blood loss was recorded for the robotic group (50 ml [IQR: 50] vs 100 ml [IQR: 288]; p = 0.02). The RA group presented five minor complications (16.7%) and one major (Clavien 3b) complication (3.3%), whereas four minor complications (8.7%) and one major (Clavien 3b) complication (2.3%) were observed in the LA group. No significant difference was noted between groups in terms of malignant histology (p = 0.66) and positive margin rate (p = 0.60). Distribution of pheochromocytomas in the LA group was significantly higher than in the RA group (43.5% vs 16.7%; p = 0.02).

Conclusions

The standardization of each surgical step optimizes the RA procedure. The robotic approach can be applied for a wide range of adrenal indications, recapitulating the safety and effectiveness of open surgery and potentially improving the outcomes of standard laparoscopy.

Patient summary

In this report we detail our surgical technique for robotic removal of adrenal masses. This procedure has been standardized and can be offered to patients, with excellent outcomes.     

Prevalence of dental fluorosis in school children from Marinópolis,São Paulo

The purpose of this study was to determine the frequency and severity of dental fluorosis in 5 to 12 and 15 year-old school children in the city of Marinópolis, S?o Paulo, Brazil, with the purpose of obtaining a baseline data for the monitoring dental fluorosis in this population. All of the school children in the both sexes, in the mentioned ages, enrolled in educational institutions and having the pre-requirement condition of to live in Marinópolis from their birth were involved, totaling 320 school children. The exams were made by one examiner previously calibrated to use the Dean Index. According to the results, the frequency of dental fluorosis in the studied group was 17.2%, however just considering the fluorosis levels that determine aesthetic compromising (mild, moderate and severe), this percentile was 7.19%. The predominant level was the very mild (10.0%) followed for the mild (5.3%), moderate (1.3%) and severe (0.6%). Concluding that the dental fluorosis in the studied population doesn't constitute in a problem with wide dimensions, however, subsequent studies are necessary in the attempt of identifying the causes of moderate and severe fluorosis cases.     

Real-time quantitative RT-PCR identifies distinct c-RET, RET/PTC1 and RET/PTC3 expression patterns in papillary thyroid carcinoma

RET/PTC1 and RET/PTC3 are the markers for papillary thyroid carcinoma. Their reported prevalence varies broadly. Nonrearranged c-RET has also been detected in a variable proportion of papillary carcinomas. The published data suggest that a wide range in expression levels may contribute to the different frequency of c-RET and, particularly, of RET/PTC detection. However, quantitative expression analysis has never been systematically carried out. We have analyzed by real-time RT-PCR 25 papillary carcinoma and 12 normal thyroid samples for RET/PTC1, RET/PTC3 and for RET exons 10-11 and 12-13, which are adjacent to the rearrangement site. The variability in mRNA levels was marked and four carcinoma groups were identified: one lacking RET/PTC rearrangement with balanced RET exon levels similar to those of the normal samples (7/25 cases, 28%), the second (6/25 cases, 24%) with balanced RET expression and very low levels of RET/PTC1, the third with unbalanced RET exons 10-11 and 12-13 expression, high RET/PTC1 levels but no RET/PTC3 (7/25 cases, 28%), and the fourth with unbalanced RET expression, high RET/PTC1 levels and low levels of RET/PTC3 (5/25 cases, 20%). Papillary carcinomas with high RET/PTC1 expression showed an association trend for large tumor size (P=0.063). Our results indicate that the variability in c-RET and RET/PTC mRNA levels contributes to the apparent inconsistencies in their reported detection rates and should be taken into account not only for diagnostic purposes but also to better understand the role of c-RET activation in thyroid tumorigenesis.