Reducing inflow occlusion,occlusion duration and blood loss during hepatic resections

Background

To assess the changes in blood loss during hepatic resection with improved haemostatic devices such as a bipolar sealing device and a topical haemostatic agent.

Methods

This retrospective clinical study of prospectively collected data will assess hepatic resections performed by a single surgeon between 2005 and 2013, with the introduction of the two haemostatic techniques in 2009.

Results

A total of 371 hepatic resections (214 from 2005 to 2008 and 157 from 2009 to 2013) were included in this study. Compared with the conventional hepatic resection (2005–2008), the use of haemostatic techniques (2009–2013) significantly reduced the need for inflow occlusion (OR: 0.37, 95% CI: 0.24–0.57, P < 0.001), overall occlusion time (20.8 min versus 25.9 min, P = 0.04) and transfusion requirement (4.6% versus 12%, OR: 0.35, 95% CI: 0.14–0.90, P = 0.02). Mean overall blood loss was reduced post‐2009; however, the decrease was not statistically different (401.3 mL versus 470.8 mL, P = 0.27). Subgroup analysis revealed that blood loss was more than halved post‐2009 compared with pre‐2009 for patients who received pre‐operative chemotherapy (324.6 mL versus 738.5 mL, P = 0.005).

Conclusion

The use of a bipolar sealing device and a topical haemostatic agent reduces the need for inflow occlusion, overall occlusion time and transfusions in all patients compared with conventional hepatic resections.     

Ultra violet-induced localized inflammatory hyperalgesia in awake rats and the role of sensory and sympathetic innervation of the skin

Exposure to mid range ultrat violet radiations (UVBs) has been shown to produce systemic inflammation and hyperalgesia in mice [Saadé, N.E., Nasr, I.W., Massaad, C.A., Safieh-Garabedian, B., Jabbur, S.J., Kanaan, S.A., 2000. Modulation of ultraviolet-induced hyperalgesia and cytokine upregulation by interleukins 10 and 13. Br. J. Pharmacol. 131, 1317-1324]. Our aim was to characterize a new rat model of localized exposure to UVB and to determine the role of skin innervation in the observed hyperalgesia and cytokine upregulation. In several groups of rats one hindpaw was exposed to UVB (250-350 mJ/cm(2)) and this was followed by the application, to the plantar area of the paw, of either Von Frey hairs or a few acetone drops to measure tactile and cold allodynia, respectively. Thermal hyperalgesia was assessed by the paw withdrawal latency and duration. Cytokine levels were determined, by ELISA, in processed samples of skin tissue isolated from the exposed and non-exposed paws. UVB induced a biphasic thermal hyperalgesia and cold and tactile allodynia with an early phase that peaked at 3-6h and disappeared at 24h and a late phase with a peak at 48 h and recovery at 72-h post-exposure. Tumor necrosis factor, interleukins 1 beta, 6, 8, 10 and NGF levels were significantly increased following the same biphasic temporal pattern. Chemical ablation of capsaicin sensitive afferents and guanethidine injection produced significant alteration of the hyperalgesia and allodynia. The increase in cytokine levels by UVB was also altered by both treatments. The present study describes a new animal model for localized UVB-induced inflammatory hyperalgesia and provides evidence about the involvement of neurogenic mechanisms in the observed hyperalgesia and upregulation of proinflammatory mediators.     

Glucocorticoids do not protect against the lethal effects of experimental heatstroke in baboons

The mortality and neurological morbidity in heatstroke have been attributed to the host's inflammatory responses to heat stress, suggesting that anti-inflammatory therapy may improve outcome. We tested the hypothesis that a high dose of dexamethasone protects baboons against the lethal effects of heatstroke. Ten anesthetized baboons (Papio hamadryas) were assigned randomly to dexamethasone (n = 5) or control group (n = 5). Dexamethasone (2 mg/kg i.v.) was administered in four divided doses every 6 h starting immediately before heat stress and continuing during cooling. All animals were heat-stressed in a prewarmed neonatal incubator at 44 degrees C to 47 degrees C until systolic blood pressure fell less than 90 mmHg and then cooled passively at the ambient temperature. Mortality and neurological morbidity were noted, and biochemical markers of tissue injury/organ dysfunction were determined. Circulating interleukin (IL) 6 and complement components (C3 and C4) were measured sequentially. All heat-stressed animals had systemic inflammation indicated by increased plasma IL-6 and decreased C3 and C4 levels. Dexamethasone attenuated the complement system activation and maintained a higher plasma concentration of IL-6, with a significant augmentation of arterial blood pressure. Dexamethasone did not prevent the occurrence of severe heatstroke but unexpectedly aggravated significantly the tissue injury and multiorgan system dysfunction. Two animals (40%) in the control group and one in the steroid group survived (P > 0.05). Dexamethasone failed to protect the baboons from the lethal effects of heatstroke. These results do not support clinical testing of corticosteroids as beneficial in preventive or therapeutic strategies for the treatment of heatstroke in humans.     

Genetic investigation of 93 families with microphthalmia or posterior microphthalmos

Microphthalmia is a developmental eye defect that is highly variable in severity and in its potential for systemic association. Despite the discovery of many disease genes in microphthalmia, at least 50% of patients remain undiagnosed genetically. Here, we describe a cohort of 147 patients (93 families) from our highly consanguineous population with various forms of microphthalmia (including the distinct entity of posterior microphthalmos) that were investigated using a next‐generation sequencing multi‐gene panel (i‐panel) as well as whole exome sequencing and molecular karyotyping. A potentially causal mutation was identified in the majority of the cohort with microphthalmia (61%) and posterior microphthalmos (82%). The identified mutations (55 point mutations, 15 of which are novel) spanned 24 known disease genes, some of which have not or only very rarely been linked to microphthalmia (PAX6, SLC18A2, DSC3 and CNKSR1). Our study has also identified interesting candidate variants in 2 genes that have not been linked to human diseases (MYO10 and ZNF219), which we present here as novel candidates for microphthalmia. In addition to revealing novel phenotypic aspects of microphthalmia, this study expands its allelic and locus heterogeneity and highlights the need for expanded testing of patients with this condition.     

Effects of Sodium Hypochlorite Concentration and Temperature on the Cyclic Fatigue Resistance of Heat-treated Nickel-titanium Rotary Instruments

Introduction

We tested the cyclic fatigue resistance of heat-treated instruments immersed in sodium hypochlorite solution under different concentrations and temperature conditions.

Interactions of ventral tract and dorsal column inputs into the cat cuneate nucleus

In decerebrate- decerebellate cats with spinal lesions separating the dorsal column (DC) from the spinocervicothalamic and ventral tract (VT) pathways, conditioning VT stimulation activated a few, but inhibited most, of the cuneate neurons discharging to test DC stimulation. This VT input into the cuneate nucleus is mediated through the brain stem.     

Modulation of segmental mechanisms by activation of a dorsal column brainstem spinal loop

In decerebrate-decerebellate cats, dorsal column stimulation (DCst) rostral to selective dorsal funicular cuts, to prevent antidromic activation of afferent DC fibers, produced primary afferent depolarization and modulated reflexes at the lower spinal level. These findings indicate the importance of a DC-brainstem-spinal loop in explaining the effects of DC stimulation in man and experimental animals.     

Coagulant toxicity and effectiveness in a slaughterhouse wastewater treatment plant

Attempts were made in this study to examine the toxicity of polymer/alum addition to the aeration tank effluent prior to sludge flotation as practiced in a slaughterhouse wastewater treatment plant. Based on the Microtox toxicity assay, alum at concentrations 100-200 mg/L was found to slightly increase the toxicity level of slaughterhouse wastewater effluent. However, at higher concentrations (300-1000 mg/L), significant residual chronic toxicity remained in all slaughterhouse wastewater effluents, independent of the treatment process. Polymer, on the other hand, removed organics and solids, but polymer effluents are more toxic than alum at extremely low concentration. Results indicated that alum and polymer caused inhibitory effects to the system at soluble concentrations of approximately 400 and 60 mg/L and above, respectively. The data also indicated that the solids collected in both tests (polymer/alum) were much more toxic than those from the effluents. Sediment samples from the polymer tests were the most toxic. Furthermore, the effluent toxicity of the coagulants was dramatically more significant when used after the settlement of solids than when used in mixed liquor. In addition, strong correlations were observed between the observed toxicity for a series of supernatants and the coagulant concentrations of alum/polymer processes, and between supernatants and solids collected in both tests.     

Autozygome maps dispensable DNA and reveals potential selective bias against nullizygosity

PurposeCopy number variants are an important source of human genome diversity. The widespread distribution of hemizygous copy number variants in the DNA of healthy humans suggests that haploinsufficiency is largely tolerated. However, little is known about the extent to which corresponding nullizygosity (two-copy deletion) is similarly tolerated.MethodsWe analyzed a cohort of first cousin unions to enrich for shared parental hemizygous events and tested their Mendelian inheritance in offspring.ResultsAnalysis of autozygous DNA blocks (autozygome) in the offspring not only proved an efficient method of mapping “dispensable” DNA but also revealed potential selective bias against the occurrence of nullizygous changes. This bias was not restricted to genic copy number variants and was not accounted for by a high rate of miscarriages.ConclusionsThe autozygome is an efficient way to map dispensable segments of DNA and may reveal selective bias against nullizygosity in healthy individuals.Genet Med 2012:14(5):515–519