Pulmonary morphofunctional effects of mechanical ventilation with high inspiratory air flow

Objective: Uncertainties about the numerous degrees of freedom in ventilator settings leave many unanswered questions about the biophysical determinants of lung injury. We investigated whether mechanical ventilation with high air flow could yield lung mechanical stress even in normal animals. Design. Prospective, randomized, controlled experimental study. Setting: University research laboratory. Subjects. Thirty normal male Wistar rats (180-230 g). Interventions: Rats were ventilated for 2 hrs with tidal volume of 10 mL/kg and either with normal inspiratory air flow (V`) of 10 mL/s (F10) or high V` of 30 mL/s (F30). In the control group, animals did not undergo mechanical ventilation. Because high flow led to elevated respiratory rate (200 breaths/min) and airway peak inspiratory pressure (PIP,aw = 17 cm H2O), two additional groups were established to rule out the potential contribution of these variables: a) normal respiratory rate = 100 breaths/min and V` = 30 mL/sec; and b) PIP,aw = 17 cm H2O and V` 10 mL/sec. Measurements and Main Results: Lung mechanics and histology (light and electron microscopy), arterial blood gas analysis, and type III procollagen messenger RNA expression in lung tissue were analyzed. Ultrastructural microscopy was similar in control and F10 groups. High air flow led to increased lung plateau and peak pressures, hypoxemia, alveolar hyperinflation and collapse, pulmonary neutrophilic infiltration, and augmented type III procollagen messenger RNA expression compared with control rats. The reduction of respiratory rate did not modify the morphofunctional behavior observed in the presence of increased air flow. Even though the increase in peak pressure yielded mechanical and histologic changes, type III procollagen messenger RNA expression remained unaltered. Conclusions: Ventilation with high inspiratory air flow may lead to high tensile and shear stresses resulting in lung functional and morphologic compromise and elevation of type III procollagen messenger RNA expression.

A new morphological variant of uterine PEComas with sex-cord-like pattern and WT1 expression: more doubts about the existence of uterine PEComas

PEComas are rare neoplasms that are sometimes associated with the tuberous sclerosis complex. They typically contain perivascular epithelioid cells that coexpress muscle and melanocytic markers. However, apart from these classical features, considerable clinical, pathologic, and immunohistochemical variation has been reported. WT1, the Wilms tumor gene product, can be expressed in various tumors from different anatomical sites, including sex-cord and other ovarian tumors with a sertoliform pattern. Neither a sex-cord like pattern nor WT1 expression has been described in PEComas. Here, we describe a case of uterine PEComa with a pattern of infiltration into the myometrium that is similar to stromal sarcomas, characterized by tongues and endovascular growing. The architecture and cellular morphology were similar to sex-cord tumors, and the PEComa was diffusely and strongly positive for WT1. We reviewed, from our files, an additional 9 cases of PEComa from different sites, and found WT1 expression in one more soft tissue tumor. We discuss the relationship between PEComas and other uterine sarcomas. (C) 2010 Elsevier Inc. All rights reserved.

Flow-through peritoneal dialysis in neonatal enema-induced hyperphosphatemia

Fleet enemas are hypertonic solutions with an osmotic action and a high concentration of phosphate. When retained in the human body they have a great toxic potential, causing severe hydro-electrolyte disorders in children, especially in newborns. We report the case of a previously healthy 8-day-old newborn who needed neonatal intensive care treatment after the inadvertent administration of an osmotically active hypertonic phosphate enema. Taking into account that phosphate removal by peritoneal dialysis (PD) strongly depends on total dialysate turnover, we chose continuous flow PD (CFPD) as the treatment option, with a successful outcome. Clinical experience with this dialytic modality is limited to a few case reports in pediatric and adult patients. To the best of our knowledge, we report here the first description of CFPD in the setting of acute phosphate nephropathy in the neonatal period. The modality of PD described here has potential as an alternative management option as it is a highly efficient, methodologically simple, and low-cost method without any need for sophisticated equipment. Physicians and parents should be aware of the adverse effects of a hypertonic phosphate enema and should never use these medications in infants and newborns.

Iliac-hepatic arterial bypass for compromised collateral flow during modified Appleby operation for advanced pancreatic cancer

Involvement of the celiac trunk and common hepatic artery are two of the most common forms of vascular invasion by tumours of the distal pancreas, and until recently this finding was considered a contra-indication to resection. We described a modified Appleby operation for locally advanced distal pancreatic cancer with compromised hepatic collateral flow that needed hepatic arterial revascularization, successfully accomplished by left external iliac-hepatic arterial bypass with Dacron prosthesis. Patient recovery was uneventful and he was discharged on the 10th postoperative day. Postoperative angio-CT disclosed a patent arterial bypass. Patient is well and asymptomatic 13 months after operation. At the time of this writing, postoperative CT scan showed no evidence of disease and CA 19-9 level is normal. There is a well established rationale to perform extended resection of pancreatic carcinomas that compromise vascular structures. Modified Appleby procedure can safely be performed, has oncological advantages to palliative procedures and provides relief of pain but is reserved for selected patients. Preservation of hepatic arterial flow has utmost importance to avoid hepatobiliary complications as liver necrosis, liver abscess, gallbladder necrosis or cholecystitis. In this case, hepatic revascularization was particularly challenging, but was successfully accomplished by left external iliac-hepatic arterial bypass. To our knowledge this type of arterial bypass has never been described so far in the English literature and its description may be important for surgeons dealing with advanced pancreatic cancer. (C) 2009 Elsevier Ltd. All rights reserved.

Comparative Study of the Standard Fluorescent Antibody to Membrane Antigen (FAMA) Assay and a Flow Cytometry-Adapted FAMA Assay To Assess Immunity to Varicella-Zoster Virus

A flow cytometry-adapted fluorescent antibody to membrane antigen (FAMA) assay to detect IgG antibodies against varicella-zoster virus (VZV) was developed and tested in 62 serum samples, showing 90.32% accuracy obtained from a receiver operating characteristic (ROC) curve with a 0.9125 (95% confidence interval [CI], 0.829 to 1.00) area below the curve compared to the result with standard FAMA.

Eruptive xanthoma with unexpected granuloma annulare-like microscopic appearance - Case report

Eruptive xanthoma with unexpected granuloma annulare-like microscopic appearance - Case report Abstract: Eruptive xanthoma and granuloma annulare are dermatological diseases with different clinical findings that, sometimes, exhibit histopathological similarities with potential for misinterpretation. We report a case of an eruption of yellow-orange papules with erythematous borders in a 34-year-old male with high levels of serum triglycerides and cholesterol. The skin biopsy specimen has diagnosed granuloma annulare. Review of the histologic material revealed eruptive xanthoma. Remission of the eruption after treatment of dyslipidemia confirmed the diagnosis of the eruptive xanthoma and motivated research about the histological similarities and differences between these diseases.

Toll-like receptor activity in Recurrent Aphthous Ulceration

Toll-like receptors (TLR) are membrane proteins that recognize conserved molecules derived from bacterial, virus, fungal or host tissues. Activation of TLRs causes the production of cytokines that mediate inflammatory responses and drive T helper (Th) 1 and 2 cell development. As an exaggerated Th1 immune response is supposed to be involved in pathogenesis of Recurrent Aphthous Ulceration (RAU), we suggest that RAU patients may have an imbalance in TLR pathways. To study the function of TLR activation ex vivo, peripheral blood mononuclear cells (PBMCs) from RAU patients (n = 17) and controls (n = 17) were exposed to TLR2 [lipoteichoic acid (LTA), heat-killed Listeria monocytogenes (HKLM) and PamC3CSK4], TLR3 [Poly(I:C)], TLR4 [lipopolysaccharide (LPS)], TLR5 (flagellin) and TLR7 (imiquimod) ligands, and the time course of supernatant tumor necrosis factor-alpha (TNF-alpha) levels was quantified by enzyme-linked immunosorbent assay. In addition, serological and salivary TNF-alpha and soluble CD14 levels were quantified. The TNF-alpha produced by PBMCs in contact with each TLR ligand and autologous serum or saliva at the same time was also investigated. The data were analyzed by statistical multivariate tests. The control group had a higher response to LTA, whereas RAU had a higher response to HKLM. LTA and LPS interfered with the salivary stimulation of the RAU PBMC and HKLM with the stimulation of the control. Autologous serum was capable of inhibiting TLR2 responsiveness to LTA and enhancing LPS stimulation. Salivary and serological levels of sCD14 and TNF-alpha were not significantly different. Recurrent Aphthous Ulceration patients have an anomalous activity of the TLR2 pathway that probably influences the stimulation of an abnormal Th1 immune response.

Fetal hemodynamic changes following maternal betamethasone administration in pregnancies with fetal growth restriction and absent end-diastolic flow in the umbilical artery

Objectives. To examine the effects of betamethasone administration on umbilical artery (UA), middle cerebral artery (MCA) and ductus venosus (DV) Doppler flow. Design. Longitudinal prospective study. Setting: Fetal Surveillance Unit, Department of Obstetrics and Gynecology, University of Sao Paulo, Sao Paulo, Brazil. Population. Thirty-two singleton pregnancies complicated by fetal growth restriction with absent end-diastolic flow in the UA. Methods. Pulsatility index (PI) of the UA, MCA and DV was measured from 26 to 34 weeks prior to and within 24 or 48 hours after starting betamethasone treatment course. Analysis of variance for repeated measures was used to determine the changes in the fetal hemodynamic Doppler flow following maternal corticosteroid administration. Main outcome measures. Improvement of UA-PI within 24 hours and DV-PIV (venous pulsatility) within 48 hours from the first betamethasone dose. Results. Mean gestational age at delivery was 29.3 (1.8) weeks and birthweight was 806.6 (228.2) g. A reduction in the UA-PI was observed in 29 (90.6%) cases, with return of end-diastolic flow in 22 (68.7%). The mean UA-PI were 2.84 (0.52) before corticosteroid administration, 2.07 (0.56) within 24 hours and 2.42 (0.75) after 48 hours, with a significant difference along the evaluations (p0.001). No significant changes in the MCA Doppler were observed. DV-PIV decreased from 1.06 (0.23) prior corticosteroids administration to 0.73 (0.16) within 24 hours and 0.70 (0.19) after 48 hours (p0.001). Conclusions. There was reduction in the umbilical artery and in the DV pulsatility indices within 24 hours from betamethasone administration that was maintained up to 48 hours.

Initial hepatosplanchnic blood flow distribution and oxygen metabolism in experimental model of hypotensive brain death

Background: Organs from the so-called marginal donors have been used with a significant higher risk of primary non function than organs retrieved from the optimal donors. We investigated the early metabolic changes and blood flow redistribution in splanchnic territory in an experimental model that mimics marginal brain-dead (BD) donor. Material/Methods: Ten dogs (21.3 +/- 0.9 kg), were subjected to a brain death protocol induced by subdural balloon inflation and observed for 30 min thereafter without ally additional interventions. Mean arterial and intracranial pressures, heart rate, cardiac output (CO), portal vein and hepatic artery blood flows (PVBF and HABF, ultrasonic flowprobe), and O(2)-derived variables were evaluated. Results: An increase in arterial pressure, CO, PVBF and HABF was observed after BD induction. At the end, an intense hypotension with normalization in CO (3.0 +/- 0.2 VS. 2.8 +/- 2.8 L/min) and PVBF (687 +/- 114 vs. 623 +/- 130 ml/min) was observed, whereas HABF (277 33 vs. 134 28 ml/min, p<0.005) remained lower than baseline values. Conclusions: Despite severe hypotension induced by sudden increase of intracranial pressure, the systemic and splanchnic blood flows were partially preserved without signs of severe hypoperfusion (i.e. hyperlactatemia). Additionally, the HABF was mostly negatively affected in this model of marginal BD donor. Our data suggest that not only the cardiac output, but the intrinsic hepatic microcirculatory mechanism plays a role in the hepatic blood flow control after BD.

Change in blood flow velocity demonstrated by Doppler ultrasound in upper limb after axillary dissection surgery for the treatment of breast cancer

The aim of this study was to evaluate the arterial and venous blood flow in women who underwent upper limb axillary dissection surgery for the treatment of breast cancer. Sixty women were divided into two groups: group 1 (G1)-30 women who underwent breast surgery with axillary dissection level II or III (55.6 +/- A 8.6 years); group 2 (G2)-control, 30 women with no breast cancer (57.4 +/- A 7.0 years). Blood flow profile was evaluated by a continuous wave ultrasound Doppler device (Nicolet Vascular Versalab SE(A (R))) with an 8 MHz probe. Axillary, brachial arteries and veins, arm circumference, volumes, and the ankle-brachial index (ABI) were examined. Wilcoxon test and Mann-Whitney tests were applied to analyze blood flow velocity intra-group and between G1 and G2, respectively. The G1 results showed no lymphedema and no peripheral arterial disease (ABI > 0.9). Moreover, the mean blood flow velocity of the vessels ipsilateral to the surgery was significantly higher than the contralateral ones for all vessels examined (P < 0.05). The mean velocity of blood flow of the vessels contralateral to surgery was significantly higher than the axillary artery in G2 (P < 0.05). It can be concluded that women who underwent axillary dissection due to breast cancer showed probable stenosis in the arterial and venous axillary and brachial vessels of the upper limb ipsilateral to the surgery, confirmed by the increase of blood flow velocity, and such obstruction might affect the limb contralateral to the operation site.

Mesenchymal Stem Cell Properties of Periodontal Ligament Cells From Deciduous and Permanent Teeth

Background: Human postnatal stem cells have been identified in periodontal ligaments (PDLs). In this study, the in vitro biologic properties of CD105(+) enriched cell subsets from PDLs harvested from deciduous (DePDL) and permanent (PePDL) teeth are comparatively assessed. Methods: PDL tissue was obtained from 12 teeth (six primary and six permanent) from which CD105(+) CD34(-) CD45(-) cells were isolated by magnetic cell sorting. To identify and quantitatively compare the stem cell markers, DePDL and PePDL cells were assessed for CD166 surface antigen expression by flow cytometry, real-time polymerase chain reaction, and immunostaining for Stro-1 and Oct-4, osteogenic and adipogenic differentiation, and proliferation rate by trypan blue method. Results: Magnetic cell sorting isolated cell populations containing 23.87% (+/- 11.98%) and 11.68% (+/- 6.27%) of CD105(+) expressing cells from PePDL and DePDL, respectively. Flow cytometric analysis demonstrated a higher proportion of CD105(+) cells coexpressing CD166 surface antigen in PePDL, whereas immunostaining and real-time polymerase chain reaction analysis demonstrated that both cell subsets expressed Stro-1 and Oct-4. DePDL-CD105(+) subsets were more proliferative compared to PePDL subsets, and both cell populations showed multipotential capabilities to differentiate in vitro to osteoblast/cementoblast- and adipocyte-like cells. However, a higher expression of adipogenic-related genes was observed in DePDL cells, whereas PePDL-CD105(+) cell subset presented a more homogeneous osteoblast/cementoblast response. Conclusion: These findings demonstrate that highly purified mesenchymal progenitor cell subsets can be obtained from the PDLs of both deciduous and permanent teeth, and further indicate phenotype dissimilarities that may have an impact on their clinical applications. J Periodontol 2010;81:1207-1215.

Insulin-like peptide genes in honey bee fat body respond differently to manipulation of social behavioral physiology

Nutrient sensitive insulin-like peptides (ILPs) have profound effects on invertebrate metabolism, nutrient storage, fertility and aging. Many insects transcribe ILPs in specialized neurosecretory cells at changing levels correlated with life history. However, the major site of insect metabolism and nutrient storage is not the brain, but rather the fat body, where functions of ILP expression are rarely studied and poorly understood. Fat body is analogous to mammalian liver and adipose tissue, with nutrient stores that often correlate with behavior. We used the honey bee (Apis mellifera), an insect with complex behavior, to test whether ILP genes in fat body respond to experimentally induced changes of behavioral physiology. Honey bee fat body influences endocrine state and behavior by secreting the yolk protein precursor vitellogenin (Vg), which suppresses lipophilic juvenile hormone and social foraging behavior. In a two-factorial experiment, we used RNA interference (RNAi)-mediated vg gene knockdown and amino acid nutrient enrichment of hemolymph (blood) to perturb this regulatory module. We document factor-specific changes in fat body ilp1 and ilp2 mRNA, the bee`s ILP-encoding genes, and confirm that our protocol affects social behavior. We show that ilp1 and ilp2 are regulated independently and differently and diverge in their specific expression-localization between fat body oenocyte and trophocyte cells. Insect ilp functions may be better understood by broadening research to account for expression in fat body and not only brain.

The macrophage-derived neutrophil chemotactic factor, MNCF: A lectin with TNF-alpha-like activities on neutrophils

The macro phage-derived neutrophil chemotactic factor (MNCF) is an alpha-galactoside-binding lectin, known to induce dexamethasone-insensitive neutrophil recruitment. We further characterized MNCF effects on neutrophils and showed that it shares with TNF-alpha the ability to delay apoptosis and to trigger degranulation. MNCF and TNF-alpha effects show similar kinetics and involve Src kinases and MAPKinases dependent pathways. They were, however, clearly distinguished, since the soluble TNF-receptor etanercept prevented TNF but not MNCF effects, while melibiose disaccharide inhibited MNCF but not TNF effects. Absorption of MNCF on detoxi-gel did not alter its properties, precluding an LPS contamination effect. By contrast, galectin-3 required LPS to activate neutrophils. Specific antibodies allowed to further demonstrate that MNCF and galectin-3 are two distinct molecules. Finally, MNCF- and IL-8-induced neutrophil activation differed by their kinetic and sensitivity to pertussis toxin. In conclusion, MNCF is a distinct neutrophil agonist, with pro-inflammatory activities involving its carbohydrate recognition domain. (C) 2008 Elsevier Inc. All rights reserved.

The insulin signaling pathway in honey bee (Apis mellifera) caste development - differential expression of insulin-like peptides and insulin receptors in queen and worker larvae

The insulin/insulin-like signaling (IIS) pathway is an evolutionarily conserved module in the control of body size and correlated organ growth in metazoans. In the highly eusocial bees, the caste phenotypes differ not only in size and several structural features but also in individual fitness and life history. We investigated the developmental expression profiles of genes encoding the two insulin-like peptides (AmILP-1 and AmILP-2) and the two insulin receptors (AmInR-1 and AmInR-2) predicted in the honey bee genome. Quantitative PCR analysis for queen and worker larvae in critical stages of caste development showed that AmILP-2 is the predominantly transcribed ILP in both castes, with higher expression in workers than in queens. Expression of both InR genes sharply declined in fourth instar queen larvae, but showed little modulation in workers. On first sight, these findings are non-intuitive, considering the higher growth rates of queens, but they can be interpreted as possibly antagonistic crosstalk between the IIS module and juvenile hormone. Analyzing AmInR-1 and AmInR-2 expression in ovaries of queen and worker larvae revealed low transcript levels in queens and a sharp drop in AmInR-2 expression in fifth instar worker larvae, indicating relative independence in tissue-specific versus overall IIS pathway activity. (C) 2008 Elsevier Ltd. All rights reserved.

Turbulent blood flow plays an essential localizing role in the development of atherosclerotic lesions in experimentally induced hypercholesterolaemia in rats

Taking into account that atherosclerosis is a focal disease and high levels of plasma cholesterol are closely correlated with its pathogenesis, it is a challenge to explain how equal concentrations of cholesterol bathing the endothelium can produce local, rather than global, effects on arteries. The focal distribution of atherosclerotic lesions has been considered to be dependent, at least in part, on hydrodynamic factors. The present study was carried out to further test the hypothesis that these forces are an important localizing factor in rats feeding a hypercholesterolaemic diet and submitted to infra-diaphragmatic aortic constriction. These animals develop a normotensive prestenotic region with laminar blood flow that serves as control for a normotensive poststenotic region with turbulent blood flow. Our findings clearly demonstrated that the combination of turbulent blood flow and low wall shear stress (WSS) in the presence of hypercholesterolaemia and oxidative stress creates conditions to the formation of focally distributed incipient atherosclerotic lesions observed in the poststenotic segment. In contrast, only diffuse fatty streaks could be observed in the normotensive prestenotic segment with laminar blood flow and normal WSS in the presence of hypercholesterolaemia and oxidative stress. Although haemodynamic forces are not by themselves responsible for the pathogenesis of atherosclerosis, they prime the local vascular wall in which the lesion develop. Further studies are required to establish how haemodynamic forces are detected and transduced into chemical signalling by the cells of the artery wall and then converted into pathophysiologically relevant phenotypic changes.