Dexamethasone decreases contraction to electrical field stimulation in mesenteric arteries from spontaneously hypertensive rats through decreases in thromboxane A2 release

Glucocorticoids play a role in the control of vascular smooth muscle tone through the alteration of vasoconstrictor and vasodilator factor production. We studied the effect of dexamethasone on vasoconstriction induced by electrical field stimulation (EFS) in rat mesenteric arteries (MAs) and the role of hypertension in this effect. Endothelium-denuded MAs were obtained from Wistar-Kyoto rats and spontaneously hypertensive rats (SHRs). EFS response was analyzed by isometric tension recordings and cyclooxygenase (COX-1 and COX-2) expression by Western blot. Noradrenaline (NA) release was evaluated in segments incubated with [(3)H]NA. Dexamethasone (0.1 and 1 microM; 2-8 h) reduced vasoconstriction to EFS (200 mA, 0.3 ms, 1-16 Hz), in a dose- and time-dependent manner only in SHRs. However, the EFS-induced release of [(3)H]NA was increased in SHR arteries preincubated with dexamethasone (1 microM; 6 h). The thromboxane A(2) (TxA(2)) synthase inhibitor furegrelate (10 microM), the selective COX-2 inhibitor NS-398 (N-[2-cyclohexyloxy-4-nitrophenyl] methanesulfonamide; 10 microM), or the TxA(2) receptor antagonist SQ 29548 (1 microM), reduced EFS and NA induced vasoconstrictor responses. However, the effect of these drugs was abolished in arteries preincubated with dexamethasone. Both dexamethasone and phentolamine (1 microM) inhibited the increased thromboxane B(2) levels observed after EFS. COX-2 protein expression was reduced by dexamethasone in SHR arteries. Results suggest that dexamethasone reduces vasoconstriction to EFS in MAs from SHRs by decreasing COX-2 expression, thereby decreasing the smooth muscle TXA(2) release induced by alpha-adrenoceptor activation. The undetectable COX-2 expression in MAs from normotensive animals explains the noneffect of dexamethasone in their arteries.     

Gingival neurofibroma in a neurofibromatosis type 1 patient

Neurofibroma is a benign peripheral nerve sheath tumour. It is one of the most frequent tumours of neural origin and its presence is one of the clinical criteria for the diagnosis of type 1 neurofibromatosis (NF-I). Neurofibromatosis type 1 is an autosomal dominantly inherited disease due to an alteration in the long arm of chromosome 17. About 50% of NF-I patients have no family history of the disease. NF-I patients have skin lesions (cafe au lait spots and neurofibromas) as well as bone malformations and central nervous system tumours. Diagnosis is based on a series of clinical criteria. Gingival neurofibroma in NF-I is uncommon. Treatment of neurofibromas is surgical resection. The aim of this paper is to report a case of NF-I with gingival involvement and to review the literature.     

Non-oncotic properties of albumin. A multidisciplinary vision about the implications for critically ill patients

Introduction: Effective resuscitation with human albumin solutions is achieved with less fluid than with crystalloid solutions. However, the role of albumin in today’s critical care unit is also linked to its multiple pharmacological effects.

Areas covered: The potential clinical benefits of albumin in select populations of critically ill patients like sepsis seem related to immunomodulatory and anti-inflammatory effects, antibiotic transportation and endothelial stabilization. Albumin transports many drugs used in critically ill patients. Such binding to albumin is frequently lessened in critically ill patients with hypoalbuminemia. These changes could result in sub-optimal treatment. Albumin has immunomodulatory capacity by binding several bacterial products. Albumin also influences vascular integrity, contributing to the maintenance of the normal capillary permeability. Moreover, the albumin molecule encompasses several antioxidant properties, thereby significantly reducing re-oxygenation injury, which is especially important in sepsis. In fact, most studies of albumin administration are a combination of a degree of resuscitation with a degree of maintenance or supplementation of albumin.

Expert commentary: The potential clinical benefits of the use of albumin in selected critically ill patients such as sepsis seem related to its immunomodulatory and anti-inflammatory effects, antioxidant properties, antibiotic transportation and endothelial stabilization. Additional studies are warranted to further elucidate the underlying physiologic and molecular rationale.     

Custom designed radial forearm free flap for reconstruction of nasomaxillary defects: Report of two cases

Nasal amputation and nasomaxillary defects, need to reconstruct the internal lining, osteochondral structure, and external coating of the nose. Authors report a 70-year-old male and a 65-year-old female treated for nasomaxillary defects (Brown JS, Shaw RJ. The Lancet Oncology 2010;11:1001–1008) due to squamous cell carcinoma (SCC) where the tip of the nose was preserved. A new custom design of the radial forearm free flap (RFFF) consisting on a subcutaneous tissue (SCT) component, a skin paddle for the internal nasal vault lining, and a skin paddle for the external nasal skin coating was raised to treat both total thickness nasal defects. The dimension of each skin paddle corresponds to the defect measurements. The skin incisions of the custom design correspond to those of a conventional RFFF. The SCT component was harvested in a subcutaneous plane continuously with the skin island for the internal nasal lining which is drawn on the ulnar skin of the forearm. The component for the external nasal coating was drawn on the radial skin area of the flap. No postoperative complications and a satisfactory outcome was reported after 1 year of follow-up. This new custom design of the RFFF is described for reconstruction of nasomaxillary defects when the tip of the nose is preserved.     

Oscillatory resistance measured during noninvasive proportional assist ventilation.

Setting proportional assist ventilation (PAV) requires the measurement of patient resistance and elastance. To avoid patient sedation/paralysis or the use of an esophageal balloon, noninvasive PAV is indirectly set by the "runaway" method or in accordance with patient comfort. The aim of this study was to ascertain whether the forced oscillation technique (FOT) applied by the ventilator during noninvasive PAV is useful in assessing patient respiratory resistance. Nasal PAV was applied to 14 patients with severe chronic obstructive pulmonary disease. During PAV a modified ventilator applied a 5-Hz pressure oscillation to noninvasively assess FOT resistance (Rrs). Lung resistance (RL) was measured in seven of the patients by using an esophageal balloon. Moreover, measurements were also performed in five of the patients when PAV was applied through the mouth. Rrs was close to RL both during nasal (Rrs = 8.9 +/- 3.1, RL = 9.0 +/- 2.6; cm H(2)O x s/L; n = 7, p > 0.05) and mouth (Rrs = 5.6 +/- 2.1, RL = 5.8 +/- 1.4; cm H(2)O x s/L; n = 5, p > 0.05) breathing. Rrs was slightly greater than the maximum value of flow assistance applied during the setting of PAV (FAmax): 11.1 +/- 5.4 and 9.5 +/- 2.9 cm H(2)O x s/L, respectively (n = 14, p > 0.05), both variables being significantly correlated (r = 0.72, p < 0.05). FOT applied by the PAV ventilator allowed the assessment of patient resistance. These results suggest that FOT could be useful in setting PAV flow assistance and in automatically and continuously updating this setting in accordance with patient resistance.     

Effectiveness of continuous positive airway pressure in mild sleep apnea-hypopnea syndrome

The aim of this trial was to evaluate the effectiveness of continuous positive airway pressure (CPAP) in patients with mild sleep apnea- hypopnea syndrome (SAHS). One hundred forty-two consecutive patients with mild SAHS (apnea-hypopnea index 10-30, without severe sleepiness) were randomly assigned to receive conservative treatment (CT)-sleep hygiene and weight loss-(65 patients) or CT plus CPAP (77 patients), and 125 patients (86% males, age: 54 +/- 9 yr, BMI: 29 +/- 4 kg/m(2), AHI: 20 +/- 6, ESS: 12 +/- 4) completed the follow-up. The following outcomes were assessed at inclusion and after 3 and 6 mo of treatment: sleepiness (Epworth scale, multiple sleep latency test [MSLT]), other symptoms related to SAHS, cognitive function, and perceived health status (Functional Outcomes of Sleep Questionnaire [FOSQ], Nottingham Health profile). The relief of SAHS-related clinical symptoms was significantly greater in the CPAP group than in the CT group; the Epworth scale and FOSQ also showed more improvement in the CPAP group but did not reach significance. There were no significant differences in the other tests performed probably because the baseline values were normal. CPAP compliance was 4.8 +/- 2.2 h and treatment continuation was accepted by 62% of the patients at the end of the study. These results suggest that CPAP can be considered in treating patients with mild SAHS on the basis of an improvement in symptoms.     

Detection of carbapenemases and other mechanisms of enzymatic resistance to β-lactams in Enterobacteriaceae with diminished susceptibility to carbapenems in a tertiary care hospital

Introduction

Our objective was to characterize the enzymatic β-lactam resistance in clinical Enterobacteriaceae isolates with diminished susceptibility to carbapenems from 2013 to 2014 at Hospital Universitario Miguel Servet.

Hypertransaminasemia: indication for the diagnosis of celiac disease

A high percentage of diagnosed cases of coeliac disease are oligosymptompatic. Various atypical manifestations such as hypertransaminasemia may guide diagnosis when the disease is suspected. We present two cases of coeliac disease, which were diagnosed on the basis of hypertransaminasemia of unknown origin. One of the patients lacked the gastrointestinal symptoms suggestive of disease. We also retrospectively review (January 1990-December 1998) all the cases of coeliac disease diagnosed in our center in order to establish the frequency of liver enzyme alterations in patients with coeliac disease and their evolution on a gluten-free diet. The importance of sprue suspicion in guiding diagnosis in patients with cryptogenic hypertransaminasemia is highlighted as is the need to rule out underlying liver disease in coeliac patients with persistent hypertransaminasemia after withdrawing gluten from the diet.