Time- and Dose-Dependent Effects of Chronic Wound Fluid on Human Adult Dermal Fibroblasts

BACKGROUND Wound healing is a biologic process that is altered in patients affected by chronic venous ulcers. The wound microenvironment is reflected in the chronic wound fluid (CWF), an exudate containing serum components and tissue-derived proteins.
OBJECTIVES We investigated the effects of increasing doses of CWF collected from patients suffering from chronic venous ulcers on human adult dermal fibroblasts cultured in vitro and the relationship among CWF effects and treatment length.
METHODS Fibroblasts were treated with 60, 240, and 720 μg/mL CWF for 3 and 7 days. We evaluated cell proliferation and viability by MTT and Trypan blue assay, cell morphology by light microscopy, F-actin microfilaments organization by tetramethylrhodamine B isothiocyanate-conjugated phalloidin, α-smooth muscle actin expression by immunofluorescence, and senescence-associated β-galactosidase activity.
RESULTS CWF induced an increase in cell proliferation in the first 3 days of treatment. In contrast, at 7 days, a strong decrease in cell viability was observed. These changes were related to a cytoskeletal F-actin reorganization and not to fibroblast–myofibroblast differentiation nor to changes in cellular senescence.
CONCLUSIONS This study shows a dose-dependent and biphasic effect of CWF on dermal fibroblasts, suggesting that a continuous exposure to chronic wounds microenvironment may induce late cellular dysfunctions possibly involved in the delayed wound healing.     

Near‐infrared spectroscopy correlates with continuous superior vena cava oxygen saturation in pediatric cardiac surgery patients

Background: Cerebral regional oxygen saturation (rSO₂) measured with near‐infrared spectroscopy (NIRS) has a well‐proven clinical utility. A goal‐oriented treatment based on the rSO₂ resulted in a significant reduction in major morbidity and in a shortening of postoperative hospital stay in patients undergoing coronary revascularization. In this study, we have compared the values of superior vena cava saturation (ScvO₂) continuously measured with a Pediasat catheter and the corresponding NIRS rSO₂ values obtained during cardiac operations in pediatric patients. Methods: This was a prospective observational study enrolling fifteen pediatric patients (age: 6 days–7 years) undergoing cardiac operations. ScvO₂ data obtained with the Pediasat during the operation were compared with simultaneously recorded NIRS rSO₂ values. Results: One hundred and seventeen matched sets of data were obtained during the operation. ScvO₂ continuously measured with the Pediasat was significantly correlated with the corresponding NIRS rSO₂ values. However, there was a constant positive bias (ScvO₂ values were higher than NIRS rSO₂ values) of 5.6%, with a precision of 10.4%. Time‐related percentage changes of NIRS rSO₂ were significantly correlated with the corresponding ScvO₂ percentage changes. A decrease in ScvO₂ is predictive for a decrease in rSO₂ with a sensitivity of 73.7% and a specificity of 85.7%. Conclusions: The continuous measurement of ScvO₂ values obtained by the Pediasat may provide useful information about the metabolic conditions of the brain during cardiac operations in pediatric patients if considered as percentage changes. Absolute values of ScvO₂ tend to overestimate the correspondent rSO₂ values.     

Surgical closure of patent ductus arteriosus reduces the cerebral tissue oxygenation index in preterm infants: a near-infrared spectroscopy and Doppler study

BACKGROUND: The aim of this study was to investigate the effects of patent ductus arteriosus (PDA) ligature on cerebral oxygen saturation, cerebral blood volume (CBV) and cerebral blood flow velocity by means of near-infrared spectroscopy (NIRS) and transcranial Doppler simultaneous examinations. METHODS: This is an observational study considering 16 babies of gestational age 24-34 weeks diagnosed with PDA who underwent surgical ligation. The cerebral oxygen saturation, CBV and blood gases values were obtained 35 min before ligation, so also around the 14th and 27th min after the clip's insertion. RESULTS: Cerebral oxygen saturation, measured as tissue oxygenation index (TOI), decreased significantly after PDA ligation from a basal value of 61.1 (3.8) before surgery to 56.6 (3.3) and 55.8 (2.6)%, for the 14th and 27th min, respectively (P<0.04). CBV before and after clipping was unvaried. A negative correlation was found between DeltapH and DeltaCBV after ligation (R=0.52, P=0.03), whilst a positive correlation was found between DeltaCBV and DeltaP(aCO2) (R=0.62, P=0.009). pH increased at the 27th min post-ligation. CONCLUSIONS: NIRS is a tool for obtaining information on cerebral oxygen saturation and CBV changes during surgical PDA ligation at the bedside. A fall in TOI suggests an increased oxygen extraction during PDA surgery. The lack of increase in DeltaCBV or in diastolic flow velocity show that the PDA before the clipping did not limit cerebral blood flow, the drop in TOI suggests increased oxygen consumption over the clip and the need for accurate monitoring of oxygen utilization after the surgical treatment.     

Transient sputum eosinophilia may occur over time in non‐eosinophilic asthma and this is not prevented by salmeterol

Background and Objective: Symptomatic, steroid‐naïve asthmatic patients may have low sputum eosinophil numbers. The aim of the study was to determine whether low sputum eosinophil numbers persisted over time, during treatment with salmeterol monotherapy. Methods: Forty steroid‐naïve, symptomatic asthmatic patients, with sputum eosinophils <3%, were randomized to receive open‐label salmeterol (50 µg twice a day, n = 30) or fluticasone (125 µg twice a day, n = 10) and were then assessed at 1, 3 and 6 months. All patients underwent spirometry, a methacholine challenge test and sputum induction at each visit. Symptom scores and peak expiratory flow were recorded throughout the study. Patients were permitted to withdraw from the study at any time, if they experienced exacerbations or deterioration of symptoms. Results: The average sputum eosinophil percentage remained normal (≤1.9%) in both groups over the study period. The eosinophil percentages were ≤1.9% in 65 of the 80 samples obtained from salmeterol‐treated patients throughout the study period. Eight patients had an asthma exacerbation or deterioration, during which one developed sputum eosinophilia. Twelve patients, 11 of whom were randomized to salmeterol and one to fluticasone, developed transient sputum eosinophilia at least once during the study. This was not associated with asthma exacerbation (except for one patient). Sputum neutrophil percentage did not change in either group. Conclusions: Low sputum eosinophil numbers persisted over 6 months in a majority of patients with non‐eosinophilic asthma who received salmeterol monotherapy. However, transient sputum eosinophilia occurred in 40% indicating that non‐eosinophilic asthma may not be a stable phenotype.     

Hand movements at 3 months predict later hemiplegia in term infants with neonatal cerebral infarction

Aim The aim of this study was to explore the predictive value of quantitative assessment of hand movements in 3‐month‐old infants after neonatal stroke. Method Thirteen infants born at term (five females, eight males; mean gestational age 39.4wks, SD 1.19, range 37–41wks; mean birthweight 3240g, SD 203, range 2900–3570g) with neonatal arterial ischaemic cerebral infarction, and 13 healthy infants (mean gestational age 39.1wks, range 37–41wks, SD 1.26; mean birthweight 3190g, SD 259, range 2680–3490g) were enrolled in the study. The absolute frequency and the asymmetry of global hand opening and closing, wrist segmental movements, and independent digit movements were assessed from videotapes recorded at around 12 weeks. Neurological outcome was assessed when the infants were at least 18 months old using Touwen’s neurological examination. Results Five of the 13 infants with neonatal stroke had normal neurological development, and eight had hemiplegia. Asymmetry of wrist segmental movements and the absolute frequency of independent digit movements were significantly different between infants with and without hemiplegia (p=0.006 and p=0.008, respectively). No differences were found in global hand movements. Interpretation We propose that the observed abnormalities of hand movements are the result of two different mechanisms: direct disruption of the corticospinal projection to the spinal cord, and altered modulation of the central pattern generators of general movements.