Cardiovascular, respiratory, and metabolic changes produced by pressure-supported ventilation in intensive care unit patients

The cardiovascular, respiratory and metabolic effects of pressure-supported ventilation with 7, 14 and 21 cm H2O were studied in 16 spontaneously breathing patients convalescing from severe illness. No statistically significant changes occurred in the hemodynamic variables, although CVP and urine output were increased at the higher levels of pressure support. Minute volume and blood gases did not change. Pressure-supported ventilation was associated with a statistically significant decrease in respiratory rate (p less than .002), a significant increase in tidal volume (p less than .01) and in mean airway pressure (p less than .001). Oxygen consumption, CO2 production, and resting energy expenditure were reduced by 14% to 20%, 17% to 25% and 10% to 18%, respectively, the decrease being proportional to the level of pressure support. These changes of the metabolic variables were not found to be statistically significant.     

Transcranial Doppler monitoring of middle cerebral flow velocity in a patient with a ventriculoperitoneal shunt undergoing laparoscopy

Laparoscopic surgery is possibly associated with a risk of intracranial pressure (ICP) increase due to pneumoperitoneum in patients with ventriculoperitoneal shunts (VPS). Invasive techniques for shunt pressure monitoring are not routinely used because of the possible complications. Transcranial Doppler (TCD) is a non-invasive, safe method which gives accurate information about blood-flow velocities in basal cerebral arteries and indirectly about the ICP. Moreover it is inexpensive and simple in use. We report the use of TCD for middle cerebral flow velocity monitoring in a patient with a VPS who underwent laparoscopic surgery. In the case we present, during 60?min of pneumoperitoneum, TCD showed a sustained, but not clinically significant increase of the Pulsatility Index, with a recorded maximum change of 31?%. We consider that the use of TCD may increase the safety of laparoscopic procedures in patients with preexisting VPS.     

High‐frequency p16INK4A promoter methylation is associated with histone methyltransferase SETDB1 expression in sporadic cutaneous melanoma

Epigenetic mechanisms participate in melanoma development and progression. The effect of histone modifications and their catalysing enzymes over euchromatic promoter DNA methylation in melanoma remains unclear. This study investigated the potential association of p16^INK4A promoter methylation with histone methyltransferase SETDB1 expression in Greek patients with sporadic melanoma and their correlation with clinicopathological characteristics. Promoter methylation was detected by methylation‐specific PCR in 100 peripheral blood samples and 58 melanoma tissues from the same patients. Cell proliferation (Ki‐67 index), p16^INK4A and SETDB1 expression were evaluated by immunohistochemistry. High‐frequency promoter methylation (25.86%) was observed in tissue samples and correlated with increased cell proliferation (P = 0.0514). p16^INK4A promoter methylation was higher in vertical growth‐phase (60%) melanomas than in radial (40%, P = 0.063) and those displaying epidermal involvement (P = 0.046). Importantly, p16^INK4A methylation correlated with increased melanoma thickness according to Breslow index (P = 0.0495) and marginally with increased Clark level (I/II vs III/IV/V, P = 0.070). Low (1–30%) p16^INK4A expression was detected at the majority (19 of 54) of melanoma cases (35.19%), being marginally correlated with tumor lymphocytic infiltration (P = 0.078). SETDB1 nuclear immunoreactivity was observed in 47 of 57 (82.46%) cases, whereas 27 of 57 (47.37%) showed cytoplasmic immunoexpression. Cytoplasmic SETDB1 expression correlated with higher frequency of p16^INK4A methylation and p16^INK4A expression (P = 0.033, P = 0.011, respectively). Increased nuclear SETDB1 levels were associated with higher mitotic count (0–5/mm² vs >5/mm², P = 0.0869), advanced Clark level (III‐V, P = 0.0380), epidermal involvement (P = 0.0331) and the non‐chronic sun exposure‐associated melanoma type (P = 0.0664). Our data demonstrate for the first time the association of histone methyltransferase SETDB1 with frequent methylation of the euchromatic p16^INK4A promoter and several prognostic parameters in melanomas.     

Incidence,aetiology, treatment outcome and complications of maxillofacial fractures. A retrospective study from Northern Greece

AimTo analyse the pattern of maxillofacial injuries and treatment outcomes in Northern Greece.MethodsA tertiary referral single centre hospital; retrospective chart review. Demographics, aetiology, fixation technique (Rigid Internal Fixation: RIF; Maxillomandibular Fixation: MMF) post-surgical infections, aesthetics and occlusion were recorded.ResultsOne thousand and ten males and 229 females were operated between 1998 and 2008. Mean age was 29.6 ± 13. Mean number of plates per patient was 3.96 ± 2.28. For those with midfacial fractures (n = 379) mean was 4.02 ± 2.05. For those with mandibular fractures (n = 333), mean was 2.74 ± 0.94 while those with combined mandible and midface fractures (n = 216) were treated using 5.74 ± 2.87 plates per patient. Among those treated with plates, an unadjusted 22% increased risk for post-surgical infection per plate used (OR = 1.22, 95%CI: 1.13–1.32) was found. Patients with mandibular fractures were more satisfied with their post-surgical facial appearance in contrast to those with midfacial or combined midfacial and mandibular fractures. Female patients were less satisfied with their post-surgical facial appearance than males.DiscussionThis study verified a young males predominance, a shift towards more assault related fractures –especially in females– and similar post-surgical results for MMF and RIF modalities in mandibular fractures. In those patients treated with RIF, placement of fewest plates possible to obtain stability better serves aesthetics at the same time reducing risk for post-surgical infections and malocclusion.     

Decomposition of Ag-based soldering alloys used in space maintainers after intra-oral exposure. A retrieval analysis study

Objective. The aim of this study was to evaluate the elemental alterations of Ag soldering alloys used in space maintainers after intra-oral exposure. Materials and methods. Twenty devices were fabricated by using two different soldering alloys; US (Dentaurum Universal Silver Solder, n = 10) and OS (Leone Orthodontic Solder, n = 10). All devices were manufactured by the same technician. Surface morphology and elemental quantitative analysis of the soldering alloys before and after intra-oral placement in patients was determined by scanning electron microscopy and energy-dispersive X-ray microanalysis (SEM/EDX). Statistical analysis was performed by t-test, Mann Whitney tests and Pearson's correlation. For all tests a 95% confidence level was used (α = 0.05). Results. Both soldering alloys demonstrated substantially increase in surface roughness after intra-oral aging. Statistical analysis illustrated a significant decrease in the Cu and Zn content after treatment. OS demonstrated higher Cu release than US (p < 0.05). The remaining relative concentrations of Cu and Zn after the treatment did not show any correlation (p > 0.05) with intra-oral exposure time, apart from Zn in OS (r = 0.840, p = 0.04). Conclusions. Both soldering alloys demonstrated a significant Cu and Zn reduction after intra-oral exposure that may raise biocompatibility concerns.     

A somatic mutation in the thyrotropin receptor gene in a patient with an autonomous nodule within a multinodular goiter

Thyrotropin (TSH) is the prime regulator of thyroid cell growth and function and acts through the thyrotropin receptor (TSHR) located on the surface membrane of thyrocytes. Somatic heterozygous mutations that cause TSHR activation in the absence of TSH have been found in toxic adenomas and in hot nodules of multinodular goiters. Clinically and histologically heterogeneous nodules can share common gain-of-function mutations. Mutation prevalence varies greatly and is inversely related to iodine intake of the population. We report a Greek patient presenting with subclinical hyperthyroidism due to a fast-growing autonomous hyperplastic nodule in a long-standing multinodular goiter. Direct DNA sequencing showed that the hot nodule harbored a somatic heterozygous activating TSHR mutation: substitution of glutamine for leucine in the third transmembrane helix. This mutation (L512Q) was recently described in two solitary toxic adenomas. This report expands the spectrum of mutations shared by dissimilar hot nodules, supporting a common mechanism for nonautoimmune thyroid autonomy. The identification of the L512Q substitution demonstrates that gain-of-function TSHR mutations are encountered in Greece, although iodine deficiency has been significantly corrected over the last three decades.