Total intravenous anesthesia with superficial cervical block or morphine transition in patients undergoing carotid endarterectomy.

BACKGROUND: The aim of this study was compare the Aldrete score at 5 minutes of two groups of patients undergoing carotid endarterectomy with intravenous anesthesia, receiving either anesthetic superficial cervical plexus block or intravenous morphine as transition analgesia. METHODS: After Ethics Committee approval, this randomized, controlled, double-blind, single-center study was performed on patients undergoing carotid endarterectomy, who received total intravenous anesthesia with propofol and remifentanil infusion. After intubation, each patient was randomly assigned to Block (superficial cervical block with levobupivacaine before the surgical incision), or Morphine group (standardized dose of morphine 30 minutes before the end of surgery). In the recovery room, an investigator unaware of the patient randomization recorded time to extubation, Aldrete score, pain, nausea/vomiting, and shiver at T0 (time of extubation), and at 5 (T5), 10 (T10), and 30 minutes (T30) after extubation. RESULTS: Sixty-four patients were studied. Time to extubation was 11 ± 6 min for Block and 20 ± 10 min for Morphine group (P>0.001). Median Aldrete score at T0 was 9 in the Block and 6.5 in the Morphine group (P<0.001), at T5 it was 8.5 and 7.0 (P<0.001), respectively. At T5, 29 (90.6%) Block and 8 (25%) Morphine patients had an Aldrete score ≥ 8 (P<0.001). Systolic blood pressure was higher in the Block than in Morphine patients at T0 and T5. CONCLUSION: This study demonstrates shorter time to extubation and better emergence from anesthesia when total intravenous anesthesia is associated with superficial cervical block than with morphine as transition analgesia.

PI3K keeps the balance between metabolism and cancer.

Epidemiological studies have established a positive correlation between cancer and metabolic disorders, suggesting that aberrant cell metabolism is a common feature of nearly all tumors. To meet their demand of building block molecules, cancer cells switch to a heavily glucose-dependent metabolism. As insulin triggers glucose uptake, most tumors are or become insulin-dependent. However, the effects of insulin and of other similar growth factors are not only limited to metabolic control but also favor tumor growth by stimulating proliferation and survival. A key signaling event mediating these metabolic and proliferative responses is the activation of the phosphatidylinositol-3 kinases (PI3K) pathway. In this review, we will thus discuss the current concepts of tumor metabolism and the opportunity of PI3K-targeted therapies to exploit the "sweet tooth" of cancer cells.

Endothelial function in young subjects with vaso-vagal syncope.

BACKGROUND: The aim of this study was to determine whether endothelial function and inappropriate peripheral vasomotion have a significant role in the pathogenesis of neurally mediated syncope. METHODS: In 16 patients (mean age 28.2+/-5.8 years) with previous vaso-vagal syncope and in matched healthy subjects, endothelium-dependent flow-mediated dilation (FMD) and endothelium-independent response to glyceryl trinitrate (GTN), 25 mug, were measured in the brachial artery from high-resolution ultrasonography. Heart rate variability (HRV) analysis at rest and during tilt test was compared between two groups. RESULTS: In the subjects with positive tilt test, all HRV parameters were significant higher respect to subjects with negative tilt test (P<0.001). The patients with positive tilt test, showed persistent, marked variability of heart rate (HR), due to increased vagal activity with withdrawal sympathetic tone and consequently reduction of blood pressure (BP) (-30.4+/-4.2 mmHg, P<0.001) accompanied by a decrease in HR (-24.3+/-4.5 beats/min, P<0.001) compared to negative tilt test subjects. These findings prove the real presence of vagal hypertone in patients with syncope. In our study, HR reached values lower than 40 beats/min. FMD in patients with neurally mediated syncope were significantly greater than those in controls (respectively, 9.2+/-2.8% vs. 4.6+/-1.4%, P<0.01) whereas no differences were shown in the response to GTN (18.4+/-4.4% vs. 16.1+/-4.2%, n.s.). CONCLUSIONS: The augmented endothelial function and the abnormal vasodilation of peripheral arteries in association with bradycardia play an important role in the development of vaso-vagal syncope in young subjects.

Effect of L-thyroxine treatment on left ventricular function in subclinical hypothyroidism.

Aim of this study was to investigate the effects of thyroxine treatment on myocardial regional left ventricular (LV) systolic and diastolic function in patients with subclinical hypothyroidism (SH) by tissue Doppler imaging (TDI). Forty-two patients (29 women and 13 men; mean age 52.2+/-15.1 years) with SH, as judged by elevated serum thyroid-stimulating hormone (TSH) levels (>3.6 mIU/l; range, 3.8-12.0) and free thyroid hormones (FT4 and FT3) within the normal range, and 30 euthyroid volunteers (21 women and nine men; mean age 50.4+/-17.1 years) underwent standard echocardiography and TDI-derived early (Em) and late (Am) diastolic velocities, systolic (Sm) velocity, and isovolumetric relaxation time (IVRTm). Patients were randomly assigned to receive or not L-thyroxine replacement therapy. All patients returned after 6 months to repeat thyroid function tests and the evaluation of all parameters. No significant differences were seen in the Sm peak between SH and control groups. Respect to controls, SH patients exhibited a lower Em, a higher Am, and, subsequently, a reduced Em/Am ratio of both lateral wall (LW) and interventricular septum (IVS) (P<0.001 for both). The IVRTm was distinctly longer in SH patients, as compared to controls (P<0.001). At 6 months, L-thyroxine-treated patients showed a significant increase of Em (P<0.01) and a subsequent increase of the Em/Am ratio (P<0.01), whereas IVRTm significantly reduced (P<0.05). No significant change in any of these parameters was observed in the untreated group. Our data suggest that SH is associated with a subtle, reversible impairment of myocardial function. TDI analysis detects and extends these functional defects by displaying alterations in regional myocardial function. L-T4 replacement therapy should be advised for these patients with the aim to correct preclinical cardiac dysfunction and prevent the development of clinically significant myocardial dysfunction.

The QDE-3 homologue RecQ-2 co-operates with QDE-3 in DNA repair in Neurospora crassa.

The post-transcriptional gene silencing mechanism in Neurospora crassa, called quelling, was shown to involve the products of three genes termed quelling-defective. A homologue to the qde-3 gene encoding a putative RecQ-type DNA helicase was isolated and was named RecQ-2. Characterisation of the RecQ-2 gene has revealed that it is not involved in quelling, but may co-operate with the qde-3 gene product in a pathway that repairs damage to DNA caused by the chemical mutagens methyl methanesulfonate and N-methyl- N'-nitro- N-nitrosoguanidine. These results indicate that the qde-3 RecQ helicase may have a dual role in N. crassa, either acting alone as an essential component of the quelling mechanism or together with the RecQ-2 RecQ helicase, as part of a process to repair DNA lesions during replication.

Coupling of a DNA piezoelectric biosensor and polymerase chain reaction to detect apolipoprotein E polymorphisms.

In this paper we report the coupling of the Polymerase Chain Reaction (PCR) with a piezoelectric biosensor to detect a point mutation in a human gene. Biotinylated 23-mer probes were immobilised on the streptavidin coated gold surface of a quartz crystal; streptavidin was covalently bound to the thiol/dextran modified gold surface. The hybridisation of the immobilised probes with a short sequence (23 mer) complementary, non-complementary and mismatched DNA was investigated: the device was able to distinguish the different synthetic oligonucleotides. Many cycles of measurements can be performed on the same crystal surface regenerating the single strand of DNA with 1 mM of HCl. The same hybridisation reaction was then performed using real samples of human DNA extracted from blood and amplified by PCR, following a standard procedure for genetic detection of the polymorphism of the apolipoprotein E (apoE) gene. The procedure was able to distinguish the sequences present in the different samples, which differ only in one base: in this way it was possible distinguish between different groups of genotypes with apoE typing. Experiments with 'blank' samples confirmed the absence of adsorption or non-specific effects on the quartz crystal treated with the reported procedure.