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BACKGROUND: Hyperosmolar therapy is the mainstay of treatment to reduce brain bulk and optimize surgical exposure during craniotomy. This study investigated the effect of equiosmolar doses of 7.5% hypertonic saline (HTS) and 20% mannitol on intraoperative cerebral oxygenation and metabolic status, systemic hemodynamics, brain relaxation, markers of cerebral injury, and perioperative craniotomy outcomes. METHODS: A total of 51 patients undergoing elective supratentorial craniotomy were randomly assigned to receive 7.5% HTS (2 mL/kg) or 20% mannitol (4.6 mL/kg) at scalp incision. Intraoperative arterial and jugular bulb blood samples were collected at predefined time intervals for assessment of various indices of cerebral oxygenation; multiple hemodynamic variables were concomitantly recorded. S100B protein and neuron-specific enolase levels were determined at baseline, and at 6 and 12 hours after surgery for assessment of neuronal injury. Brain relaxation and perioperative outcomes were also assessed. RESULTS: Demographic and intraoperative data, brain relaxation score, and perioperative outcomes were comparable between groups. Jugular bulb oxygen saturation and partial pressure of oxygen, arterial-jugular oxygen and carbon dioxide differences, and brain oxygen extraction ratio were favorably affected by 7.5% HTS up to 240 minutes postinfusion ( P <0.05), whereas mannitol was associated with only a short-lived (up to 15 min) improvement of these indices ( P <0.05). The changes in cerebral oxygenation corresponded to transient expansion of intravascular volume and improvements of cardiovascular performance. Increases in S100B and neuron-specific enolase levels at 6 and 12 hours after surgery ( P <0.0001) were comparable between groups. CONCLUSIONS: The conclusion is that 7.5% HTS has a more beneficial effect on cerebral oxygenation than an equiosmolar dose of 20% mannitol during supratentorial craniotomy, yet no clear-cut clinical superiority of either solution could be demonstrated.

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Transnasal transsphenoidal (TNTS) pituitary surgery is associated with short-lived but intense nociceptive stimuli which cause substantial hemodynamic perturbations that may increase blood loss and impair visualization of the surgical field. This systematic review aimed to critically appraise the clinical evidence for the efficacy and safety of various anesthetic techniques, other pharmacological modalities, and supplementary interventions by assessing intraoperative systemic hemodynamics, use of adjunct medications, quality of the surgical field, intraoperative blood loss, and recovery profiles in patients undergoing TNTS pituitary surgery. Relevant randomized clinical trials and observational studies were identified in a systematic literature search; 16 studies (13 randomized clinical trials, 3 observational studies) enrolling a total of 907 patients were identified for inclusion in this review. Propofol provided more potent hemodynamic control compared with volatile anesthetics with a sparing effect on the need for additional drugs to blunt hemodynamic responses. Recovery profiles between propofol and sevoflurane were either equivalent or favored sevoflurane, but both agents were superior to isoflurane. Regarding intraoperative analgesia, remifentanil was associated with superior hemodynamic control and recovery profiles than fentanyl. Dexmedetomidine had beneficial effects on hemodynamics, surgical field quality, recovery characteristics, and nociceptive properties compared with placebo. Although there was no clear-cut superiority of other adjunct pharmacological modalities on hemodynamic responses during surgery, regional blocks were associated with beneficial impacts on both primary and secondary outcomes. In summary, short-acting anesthetics, analgesics and dexmedetomidine seem to improve intraoperative hemodynamics, blood loss, and recovery qualities during TNTS pituitary surgery. However, definitive conclusions cannot be drawn because of methodological heterogeneity in the identified studies.

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Continuous, real-time remote monitoring through medical point--of--care (POC) systems appears to draw the interest of the scientific community for healthcare monitoring and diagnostic applications the last decades. Towards this direction a significant merit has been due to the advancements in several scientific fields. Portable, wearable and implantable apparatus may contribute to the betterment of today's healthcare system which suffers from fundamental hindrances. The number and heterogeneity of such devices and systems regarding both software and hardware components, i.e sensors, antennas, acquisition circuits, as well as the medical applications that are designed for, is impressive. Objective of the current study is to present the major technological advancements that are considered to be the driving forces in the design of such systems, to briefly state the new aspects they can deliver in healthcare and finally, the identification, categorization and a first level evaluation of them.

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Tumor necrosis factor α (TNFα) is a multifunctional cytokine that regulates various cellular processes related to spermatogenesis. Two types of cell receptors, TNFR1 and TNFR2, mediate TNFα activity. In the present study, we sought to explore the association of TNFα -857C→T, TNFR1 36A→G, and TNFR2 676T→G polymorphisms with sperm concentration and motility. Two hundred ninety men were examined during infertility investigation; of those, 170 men were normozoospermic and 120 were oligospermic. Polymerase chain reaction analysis revealed significant differences in genotype distribution of the TNFR1 36A→G polymorphism between normozoospermic and oligospermic men. Men with oligozoospermia presented TNFR1 36A/A genotypes less frequently than normozoospermic men (P < .001). The presence of the TNFR1 36G allele was significantly increased in oligospermic men (P < .001). Furthermore, the presence of the TNFR1 36G allele was associated with lower sperm concentration in normozoospermic men (P < .03) and in the total study population (P < .001), and with lower sperm motility in normozoospermic men (P < .007) and in the total study population (P < .001). No significant associations were found between TNFα -857C→T and TNFR2 676T→G polymorphisms and semen quality. The TNFR1 36A allele is associated with increased sperm concentration and motility in our series, supporting the significance of TNFR1 gene in semen quality.

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Nowadays, providing healthcare personalized services in user's intelligent space is an important issue for improving personal health, supporting predictive care and saving medical costs. In this paper, we propose an architecture for the Next Generation Service Delivery Platform (NG-SDP), suitable for composing and delivering personalized healthcare services. The core component of NG-SDP is a Context Decision Making Enabler (CDME) that assesses user contextual and bio information to yield personalized services. A prototype implementation of the proposed NG-SDP is also demonstrated. Finally a real case study demonstrates the CDME performance.

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We present what we believe is a new class of composite electromagnetic materials characterized by the concept of metamorphism, which we define in general terms. Metamorphic materials exhibit bulk electromagnetic transitions among states characterized by distinct ranges of values of their reflection coefficient. Each such state has unique physical properties induced by the corresponding values of the reflection coefficient. We present a variety of physical realizations of the concept of metamorphic materials in microwave frequencies, showing with specific metallodielectric designs how transitions among metamorphic states can be obtained at the same frequency, for fixed material geometries, by electronic reconfigurability. We further show how a given material exhibiting certain metamorphic states at a given frequency can transform into a different combination of metamorphic states at different frequencies; i.e., metamorphic materials have a useful dispersive degree of freedom.

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BACKGROUND: To evaluate whether histopathologic findings of skin in sepsis by Pseudomonas aeruginosa correlate with the clinical course. METHODS: Histological alterations after bacterial challenge by one susceptible (A) and two multidrug-resistant isolates (B and C) of P. aeruginosa were studied in 18 rabbits. Sepsis was induced by the intravenous infusion of 1 x 10(8) CFU by a catheter in the right jugular vein; blood was sampled for the estimation of tumor necrosis factor alpha (TNF-alpha) and malondialdehyde (MDA). Skin biopsies were collected along with a subcutaneous fat specimen for culture. RESULTS: The mean survival was 0.85, 1.75 and 11.00 days after challenge by isolates A, B and C, respectively. The main histologic findings of skin were: inflammation and swelling of the dermis; thickening of the endothelium and infiltration of vessel wall and lumen by polymorphonuclear leukocytes; extravasation of red blood cells, and necrobiotic changes of the hair follicles. Serum TNF-alpha was elevated in animals challenged by isolate A compared to challenge by isolates B and C. Concentrations of MDA were similar for all isolates. Mean log(10) of viable cells isolated from subcutaneous fat were 5.74, 2.74 and 1.40 after challenge by isolates A, B and C, respectively. CONCLUSIONS: Prolongation of survival was accompanied by lower serum TNF-alpha, decreased viable cells from subcutaneous fat and intensified inflammatory response in the dermis and subcutaneous tissue. These findings might be of importance for immunomodulatory intervention.

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We present the case of a patient with a hemangioma, a benign heart tumor, that is revealed incidentally during cardiac catheterization. The patient had coexisting coronary artery disease. This rare tumor remained unchanged in size, and the patient has been asymptomatic for a period of 20 years.