Peritoneal Submesothelial Stromal Cells Support Hematopoiesis and Differentiate into Osteogenic and Adipogenic Cell Lineages.

The peritoneum is a thin membrane that covers most of the abdominal organs, composed of a monolayer of mesothelial cells and subjacent submesothelial loose connective tissue. Cells from the peritoneal wall are correlated with peritoneal fibrosis and epithelial-to-mesenchymal transition. However, the distinct involvement of mesothelial or submesothelial cells in such phenomena is still not clear. Here, we propose a new strategy to obtain stromal cells from anterior peritoneal wall explant cultures. These cells migrated from peritoneal tissues and proliferated in vitro for 4 weeks as adherent fibroblast-like cells. Optical and electronic microscopy analyses of the fragments revealed a significant submesothelial disorganization. The obtained cells were characterized as cytokeratin- vimentin+ laminin+ α-smooth muscle actin+, suggesting a connective tissue origin. Moreover, at the third passage, these stromal cells were CD90+CD73+CD29+Flk-1+CD45-, a phenotype normally attributed to cells of mesenchymal origin. These cells were able to support hematopoiesis, expressing genes involved in myelopoiesis (SCF, G-CSF, GM-CSF, IL-7 and CXCL-12), and differentiated into osteogenic and adipogenic cell lineages. The methodology demonstrated in this work can be considered an excellent experimental model to understand the physiology of the peritoneal wall in healthy and pathological processes. Moreover, this work shows for the first time that submesothelial stromal cells have properties similar to those of mesenchymal cells from other origins.

Three-dimensional clustered speckle fields: theory, simulations and experimental verification.

Clustered speckle patterns are a particular type of speckles that appear when a coherently illuminated diffuser is imaged through a multiple aperture pupil mask attached to a lens. The cluster formation is the result of the complex speckle modulations of the multiple interferences produced by the apertures. In this paper, a three-dimensional analytical approach to simulate cluster speckles everywhere after the lens is presented. This approach has the possibility of including multiple aperture masks at the lens and at the diffuser, in contrast to previous works which were also limited to the description of the patterns only at the image plane. This model contributes to the development of tailor made speckle patterns that can be used in diverse optical applications, including those lying in the focus region. The approach is validated under different conditions by comparing experimental results with simulations on a statistical basis. Some aspects of possible uses of these clusters are briefly revised, such as optical trapping, manipulation and metrology.

Impact of a multidimensional infection control strategy on central line-associated bloodstream infection rates in pediatric intensive care units of five developing countries: findings of the International Nosocomial Infection Control Consortium (INICC).

PURPOSE: To analyze the impact of the International Nosocomial Infection Control Consortium (INICC) multidimensional infection control strategy including a practice bundle to reduce the rates of central line-associated bloodstream infection (CLAB) in patients hospitalized in pediatric intensive care units (PICUs) of hospitals, which are members of the INICC, from nine cities of five developing countries: Colombia, India, Mexico, Philippines, and Turkey. METHODS: CLAB rates were determined by means of a prospective surveillance study conducted on 1,986 patients hospitalized in nine PICUs, over a period of 12,774 bed-days. The study was divided into two phases. During Phase 1 (baseline period), active surveillance was performed without the implementation of the multi-faceted approach. CLAB rates obtained in Phase 1 were compared with CLAB rates obtained in Phase 2 (intervention period), after implementation of the INICC multidimensional infection control program. RESULTS: During Phase 1, 1,029 central line (CL) days were recorded, and during Phase 2, after implementing the CL care bundle and interventions, we recorded 3,861 CL days. The CLAB rate was 10.7 per 1,000 CL days in Phase 1, and in Phase 2, the CLAB rate decreased to 5.2 per 1,000 CL days (relative risk [RR] 0.48, 95% confidence interval [CI] 0.29-0.94, P = 0.02), showing a reduction of 52% in the CLAB rate. CONCLUSIONS: This study shows that the implementation of a multidimensional infection control strategy was associated with a significant reduction in the CLAB rates in the PICUs of developing countries.

Subchronic effects of nasally instilled diesel exhaust particulates on the nasal and airway epithelia in mice.

Diesel exhaust is the major source of ultrafine particles released during traffic-related pollution. Subjects with chronic respiratory diseases are at greater risk for exacerbations during exposure to air pollution. This study evaluated the effects of subchronic exposure to a low-dose of diesel exhaust particles (DEP). Sixty male BALB/c mice were divided into two groups: (a) Saline: nasal instillation of saline (n = 30); and (b) DEP: nasal instillation of 30 microg of DEP/10 microl of saline (n = 30). Nasal instillations were performed 5 days a week, over 30 and 60 days. Animals were anesthetized with pentobarbital sodium (50 mg/kg intraperitoneal [i.p.]) and sacrificed by exsanguination. Bronchoalveolar lavage (BAL) fluid was performed to evaluate the inflammatory cell count and the concentrations of the interleukin (IL)-4, IL-10, and IL-13 by enzyme-linked immunosorbent assay (ELISA). The gene expression of oligomeric mucus/gel-forming (Muc5ac) was evaluated by real-time polymerase chain reaction (PCR). Histological analysis in the nasal septum and bronchioles was used to evaluate the bronchial and nasal epithelium thickness as well as the acidic and neutral nasal mucus content. The saline group (30 and 60 days) did not show any changes in any of the parameters. However, the instillation of DEP over 60 days increased the expression of Muc5ac in the lungs and the acid mucus content in the nose compared with the 30-day treatment, and it increased the total leukocytes in the BAL and the nasal epithelium thickness compared with saline for 60 days. Cytokines concentrations in the BAL were detectable, with no differences among the groups. Our data suggest that a low-dose of DEP over 60 days induces respiratory tract inflammation.

Light-Emitting Diode (LED) Traps Improve the Light-Trapping of Anopheline Mosquitoes.

Numerous advantages over the standard incandescent lamp favor the use of light-emitting diodes (LEDs) as an alternative and inexpensive light source for sampling medically important insects in surveillance studies. Previously published studies examined the response of mosquitoes to different wavelengths, but data on anopheline mosquito LED attraction are limited. Center for Disease Control and Prevention-type light traps were modified by replacing the standard incandescent lamp with 5-mm LEDs, one emitting at 520 nm (green) and the other at 470 nm (blue). To test the influence of moon luminosity on LED catches, the experiments were conducted during the four lunar phases during each month of the study period. A total of 1,845 specimens representing eight anopheline species were collected. Anopheles (Nyssorhynchus) evansae (35.2%) was the most frequently collected, followed by An. (Nys.) triannulatus (21.9%), An. (Nys.) goeldii (12.9%), and An. (Nys.) argyritarsis (11.5%). The green LED was the most attractive light source, accounting for 43.3% of the individuals collected, followed by the blue (31.8%) and control (24.9%) lights. The LED traps were significantly more attractive than the control, independent of the lunar phase. Light trapping of anopheline mosquitoes was more efficient when the standard incandescent lamp was replaced with LEDs, regardless of the moon phase. The efficiency of LEDs improves light trapping results, and it is suggested that the use of LEDs as an attractant for anopheline mosquitoes should be taken into consideration when sampling anopheline mosquitoes.

The effects of urban particulate matter on the nasal epithelium by gender: An experimental study in mice.

Nose is the first portion of the respiratory system into contact with air pollution particles, including organic compounds that could act as endocrine releasers. The objective was to identify and quantify estrogenic receptor-ß (ERß), aryl hydrocarbon receptor (AhR), the cytochrome P450 enzymes CYP1A1, 1A2, 1B1, and mucus profile in the nasal epithelium of mice. BALB/c mice male (n = 32) and female (n = 82) in proestrus, estrus and diestrus were divided into two groups: 1) exposed to ambient air; 2) concentrated ambient particles (CAPs) to achieve an accumulated dose (concentration vs. time product) of 600 µg/m(3), the time of the exposure was controlled to ensure the same concentration for all groups (5 days per week for 40-51 days). RT-PCR (Erß-1, Erß-2, Ahr, Cyp1a1, Cyp1a2, Cyp1b1), immunohistochemistry and morphometry (ERß, AhR) were used to analyze. The mucus profiles were examined using acid (Alcian Blue) and neutral (periodic acid Schiff's) stains. Exposed females had significantly lower levels of Erß-2 mRNA than exposed males (p = 0.036). Cyp1b1 mRNA in diestrus females was significantly lower in the CAP-exposed group compared with the ambient air group (p ≤ 0.05). ERß expression in the epithelium and submucosa nucleus was lower in estrus exposed to CAPs compared with ambient air. CAPs increases AhR in the epithelium (p = 0.044) and submucosa (p = 0.001) nucleus of female when compared with male mice. Exposure to CAPs, also led to relatively increased acidic content in the mucus of males (p = 0.048), but decreased acidic content in that of females (p = 0.04). This study revealed sex-dependent responses to air pollution in the nasal epithelium that may partially explain the predisposition of females to airway respiratory diseases.

Liver granulomas in schistosomiasis: mast cell-dependent induction of SCF expression in hepatic stellate cells is mediated by TNF-alpha.

Mast cell proliferation, survival, and differentiation are under control of the surrounding stroma and are largely mediated by the stem cell factor (SCF). Mast cells are abundant in liver fibrosis and are proposed to be causally related with its persistence and intensity through secretion of fibrogenic cytokines. In normal adult liver, local connective tissue cells (stellate cells) do not constitutively express SCF. We studied primary cultures of stellate cells obtained from fibrogranulomatous reactions elicited in mouse liver by schistosomal infection. We have shown that the SCF expression can be induced in vitro by co-culture with mast cells and this induction was dependent on the release of tumor necrosis factor alpha (TNF-alpha). Because SCF induces in mast cells proliferation and release of both fibrogenic factors and TNF-alpha, the described interaction between liver stroma and mast cells represents an auto-stimulatory loop, which may explain the progressive and persistent character of liver fibrosis associated with chronic inflammations or infections. Granulomatous reactions in liver elicited by chronic schistosomiasis sustain a local production of inflammatory cells, and this extramedular myelopoiesis is potentially also dependent on the induction of SCF expression in the liver stellate cells.

The Influence of Weather and Lunar Phases on the Flight Activity of Paederus Rove Beetles (Coleoptera: Staphylinidae).

Despite the medical importance of Paederus beetles, no studies have studied the influence of the abiotic factors on the flight activity and nighttime dispersal of these insects in Brazil. Therefore, the influence of both climatic factors and moon phase on black-light catches of Paederus rove beetles was investigated. Paederus beetles were attracted to a black light source hourly from 1800 to 0600 hours, and data on weather conditions as well as moon phase data were taken for every sampling date. Overall, 543 individuals of Paederus beetles belonging to four species were captured: P. protensus, P. columbinus, P. brasiliensis, and P. mutans. Paederus beetles were mostly active in the warmest parts of the studied nights. Variations in nighttime temperature, relative humidity, wind speed, cloud cover, and moon phases appear not to affect Paederus flight. The diurnal temperature was observed to affect the night hourly dispersal of Paederus rove beetles as well as their distribution pattern during the entire period of study. The true environmental condition responsible for Paederus beetles seasonal pattern and daily night dispersal in northeastern Brazil were the annual moisture and drought cycles and the diurnal maximum temperatures, respectively. Significant trap catches were observed in the earliest hours after sunset (1800-2100), and people must be aware of this fact, as it can notably increase the risk of acquiring linearis dermatitis from the contact with large numbers of active Paederus.

Transposition of the great arteries with ventricular septal defects. Surgical considerations concerning the Rastelli operation.

We studied the anatomy of the ventricular septal defect in 20 heart specimens and eight operated patients with transposition of the great arteries regarding the feasibility of the Rastelli operation. They were divided into three groups. In Group I, comprising eight cases, creation of a left ventricle-aorta connection was not prevented by interposition of the atrioventricular valve tissue, and the ventricular septal defect was large or could be enlarged sufficiently. Thus, the Rastelli operation was feasible in all cases. In Group II, comprising 12 cases, interposition of the atrioventricular valves was not present, but the ventricular septal defect was inadequate in size for a good left ventricle-aorta connection. Small or even medium-sized ventricular septal defects were not enlargeable because of surrounding structures or inadequate septum for resection. In all cases, the ventricular septal defect was a tunnellike structure with two orifices; attempted enlargement would be more difficult at the left ventricular end (not obvious to the surgeon's view) than at the right one. The Rastelli operation was judged inadvisable in these cases. In Group III, comprising eight cases, the Rastelli operation was considered inadvisable because of interposition of atrioventricular valve tissue. The size of the ventricular septal defect and the presence of interposed atrioventricular valves can be diagnosed preoperatively. The presence of enough available space for resection, especially at the left ventricular end, should be determined preoperatively and/or intraoperatively in patients with medium-sized ventricular septal defects requiring enlargement. The anatomy of the ventricular septal defect may significantly alter the surgical approach for patients with transposition of the great arteries and ventricular septal defect.

New surgical approach to palliate tricuspid atresia in infants.

An experimental surgical technique is proposed to increase pulmonary blood flow in tricuspid atresia with normally related great arteries. The method consists of the creation of ventricular septal defect in the infundibular septum by means of a closed surgical procedure. The expected advantage would be the growth of the right ventricular cavity. This would permit performance of a Fontan's procedure later, using the right atrium and the right ventricle. Microscopic sections from the hearts of 4 infants showed no damage in the conduction system. When performed in the beating hearts of dogs, the feasibility of the procedure was tested repeatedly without production of rhythm disturbances.

Mast cells can revert dexamethasone-mediated down-regulation of stem cell factor.

Mast cell hyperplasia can be causally related with chronic inflammation and liver fibrosis. Their survival and proliferation is dependent upon locally produced growth factors, the major one being the stem cell factor (SCF). Glucocorticoids can decrease mastocytosis, down-regulating the mast cell production of pro-inflammatory factors or inhibiting the expression of SCF in stroma. We compared dexamethasone effect on SCF expression in co-cultures of mast cells with NIH/3T3 fibroblasts or with primary cultures of activated hepatic stellate cells. Dexamethasone abrogated the NIH/3T3 stroma capacity to sustain mast cell proliferation, but not of hepatic stellate cells, at the post-transcriptional level. Mast cells reverted completely dexamethasone effect on hepatic stellate cells, increasing their SCF synthesis and transport. In both models, dexamethasone inhibited the mast cell spreading on the stroma, which was thus not required for mast cell survival and proliferation. Liver pathologies associated with mast cell hyperplasia are not expected to be sensitive to glucocorticoid treatments.

Complete atrioventricular canal and tetralogy of Fallot: surgical management.

Between 1982 and 1989, nine patients with complete atrioventricular (AV) canal and tetralogy of Fallot underwent successful repair of both anomalies. Seven patients had Down's syndrome. One or more previous palliative shunts had been used in six patients. Associated cardiovascular lesions included persistent left superior vena cava (two patients), patent ductus arteriosus with marked stenosis of the left pulmonary artery (one patient). The diagnosis was confirmed by cardiac catheterization and cineangiography. Closure of the ventricular septal defect was performed through a combined right atrial and ventricular approach in each patient. The right ventricular outflow obstruction was relieved with the use of a transannular patch (4), right ventricular infundibular patch (4) or a valved external conduit (1). There were no hospital deaths. One patient died as a result of meningitis 2 years after repair. Progressive left AV valve incompetence developed in one patient requiring valve replacement. A single atrial approach may not provide the best exposure of the subaortic end of the defect. In this regard, we recommend an additional right ventriculotomy in order to ensure safe closure of the septal defect. Although an adequately shaped isolated patch could be sufficient to close the anterior VSD, we favour a separate patch to minimize the possibility of producing subaortic obstruction. A further method to avoid this subaortic stenosis consists of dividing the common anterior leaflet to the right towards the lateral extent of the infundibular septum.

Rhabdomyoma of the heart: surgical treatment.

Rhabdomyoma of the heart may cause severe hemodynamic obstruction specially in infants. Medical treatment carries a 100% mortality, but there are no clear surgical indications for these patients. Accordingly we reviewed the world literature (30 operated patients) adding our own experience (1 successfully operated patient) Based on our data and that of other we conclude: (1) Severely ill patients with rhabdomyoma should be operated upon. Age or associated tuberous sclerosis are not surgical contraindications. (2) Removal of the hemodynamic obstruction should be the main surgical goal. Radical resection of the tumor is not necessary and may be dangerous. (3) Surgical mortality is acceptable and it is becoming lower with time. (4) Long-term outcome for successfully operated patients is unknown.

Phrenic nerve paralysis following pediatric cardiac surgery. Role of diaphragmatic plication.

Eighteen children sustained unilateral phrenic nerve paralysis (PNP) after cardiac surgical procedures. Ten (Group I), under 7 months (mean: 2.9 +/- 2.2), required long-term ventilatory assistance (mean: 23.9 +/- 13.0 days); they failed to be weaned from the ventilator. All underwent diaphragmatic plication (DP). DP was performed late in 7 cases (Group Ia) with a mean time of 30.8 days between surgery and DP, and early in 3 others (Group Ib) with a mean time of 10.2 days. Eight children (Group II), older than 1 year, tolerated PNP better and could be extubated early without diaphragmatic plication. In Group Ia severe lung infections were recorded in 5 before or/and after DP, and two died at 3 and 30 days after plication. Five children from Group Ia and all 3 from Group Ib were late survivors. They could be weaned from ventilatory support in a mean time of 3 days after DP, although those with severe lung infection (Group Ia) took the longest time. All from Group II were late survivors. We conclude: PNP is well tolerated without plication in children older than 1 year. However early DP offers excellent and immediate results in infants with PNP. Early DP in these children avoids or reduces severe lung infections and death.

Aortopulmonary window with anomalous origin of the right coronary artery from the pulmonary trunk.

A case of aortopulmonary window associated with an anomalous origin of the right coronary artery from the pulmonary artery in a 3-month-old boy is reported. Angiographic diagnosis could be difficult because of the simultaneous filling of both great arteries that obscure the origin of the anomalous vessel; however, a careful evaluation of the angiogram may contribute to an accurate diagnosis. The surgical correction of this association of defects requires the connection of the aorta with the anomalous coronary ostium. An intrapulmonary tunneling procedure by means of a baffle is described.

[The angiographic diagnosis of the connection of the persistent left vena cava superior to the left atrium by the absence of the roof of the coronary sinus in a child with a Holmes' heart]. / Diagnóstico angiográfico de la conexión de la vena cava superior izquierda persistente a la aurícula izquierda por ausencia de techo del seno coronario en un niño con corazón de Holmes.

We describe a patient with angiographic findings of a left superior persistent vena cava draining in the left atrium with absence of the coronary sinus' roof and coexisting with Holmes' heart. The diagnosis can be made by selective angiography in the left atrium, pulmonary vein or at the left superior vena cava. We want to emphasize the importance of knowing this sort of anomaly before surgical treatment.

[Surgery of congenital cardiopathies without previous catheterization. Preoperative evaluation and surgical indication using bidimensional echocardiography and Doppler]. / Cirugía de las cardiopatías congénitas sin cateterismo previo. Valoración preoperatoria e indicación quirúrgica por ecocardiografía bidimensional y Doppler.

With the non-invasive devices available nowadays, many congenital heart diseases may be diagnosed with a definition comparable and even perhaps superior to catheterization and angiography. According to this issue, from January 1983 to December 1987, 239 children underwent operations for palliation or correction of different cardiopathies based on an echo-Doppler assessment without prior catheterization. Preoperative echo-Doppler diagnoses had an adequate correlation with the surgical findings in 234 cases (97.9 percent), so there was no correlation in 5 cases. In general, we consider that echo-Doppler provides a complete and definitive diagnosis in most cases, thus eliminating the need for further invasive procedures, although we still have to rely on catheterization to obtain the necessary information or reassurance in some cases. Progressive increase of reliance in echo-Doppler techniques by the surgeon and self confidence of the cardiologist in his accurate state of the art will considerably increase the performance of cardiac operations without prior catheterization in the future. At present, this is our current policy, as day after day, we are increasing the diagnoses in which we consider unnecessary the catheterization to indicate surgery.

[Complete atrioventricular canal and tetralogy of Fallot: surgical considerations]. / Canal atrioventricular completo y tetralogía de Fallot: consideraciones quirúrgicas.

Nine patients with complete atrioventricular canal and tetralogy of Fallot underwent intracardiac repair of both anomalies between 1982 and 1989. The ages of the patients ranged from 6 months to 7 years. Six of the 9 had one or more previous systemic-pulmonary artery shunts. Two-dimensional echocardiography showed diagnostic characteristics of both malformations in all patients. The diagnosis was confirmed by cardiac catheterization and cineangiography. The ventricular septal defect was repaired by a combined right atrial and ventricular approach in every patient. Outflow tract reconstruction was performed with the use of a transannular patch (4), infundibular patch (4), and a valved conduit (1). There were no hospital deaths. Meningitis was responsible for the death of a patient 2 years after repair. We recommend early palliation, complete repair in those older than 4 or 5 years, surgical technique depending on the anatomical findings, combined atrial and ventricular approach, 2 separate patches to close the ventricular septal defect in required cases, adjusted correction of the right ventricular outflow tract, and careful postoperative care.

[Atrioventricular septal defect with associated tetralogy of Fallot. Clinico-morphological aspects and surgical considerations]. / Defecto del septo atrioventricular con tetralogía de Fallot asociada. Aspectos clinicomorfológicos y consideraciones quirúrgicas.

In this work the clinical features, diagnostic methods, surgical procedures and postoperative follow-up are reviewed in 19 cases of atrioventricular septal defect with associated tetralogy of Fallot. The clinical situation was always related to the degree of pulmonary ischemia, that pointed out the urgency and need for a palliative surgical procedure before corrective surgery. There was no data in the ECG for the differential diagnosis of isolated forms of atrioventricular septal defect. In 50% of the cases the cardio-thoracic index was increased by right atrial enlargement. The diagnosis of the malformation was made in every case by means of 2D echocardiography. In 16 cases palliative surgery was done (aortic-pulmonary shunts), with one death (6.2%) due to facts unrelated to the technique. Of the 6 cases with corrective surgery (5 cases with previous shunts), one needed a mitral valve replacement (St Jude prosthesis). There was no mortality in this group and the functional status in the long-term follow-up was: 3 cases were in the functional class I and 3 cases in class II. The overall mortality for all surgical procedures carried out was 4.3%. In conclusion, we consider the use of the corrective surgery adequate to the clinical stability of the patients with atrioventricular septal defect with associated Fallot's tetralogy.

[The role of the stent in non-coronary cardiopathies]. / Papel del stent en las cardiopatías no coronarias.

INTRODUCTION: The stent has demonstrated to be a useful device in the prevention of postangioplasty coronary restenosis and it is expected to have a favourable effect as an alternative or complementary treatment of stenotic lesions in arteries or veins associated with congenital defects. The aim of this study is to analyze our experience in this setting. MATERIAL AND METHODS: From February 1992 to March 1996, 28 stenting procedures were performed in 26 patients (mean age: 8.6 +/- 0.7 years; mean weight: 26.2 +/- 3 kg). In 12 patients, stenting was single, and a iliac Palmaz stents were always used. Stenting location was: pulmonary artery branches in 17 patients, right ventricular outflow in 2 patients, in the junction of right atrium with pulmonary artery in 2 patients, systemic veins in 2 patients and in post Mustard intratrial channel stenosis in 2 patients. 25 patients had previously undergone at least one surgical procedure. RESULTS: The stenotic diameter of the treated lesions increased significantly after the procedure (4.4 +/- 0.3 mm before stenting vs 11.6 +/- 0.3 mm after stenting, p < 0.0001) and the transtenotic gradient decreased from 38.1 +/- 5 to 12 +/- 3.8 mmHg. Those changes were associated with a diminution of right ventricular pressure (81.6 +/- 3 vs 56.7 +/- 6 mmHg, p < 0.0001) in patients with pulmonary branch stenosis without septal defects. There was no mortality among the percutaneously treated patients and only one patient needed surgery. Nevertheless, one patient died after bilateral intraoperative stenting. CONCLUSION: The treatment of proximal or distal stenotic lesions in the pulmonary tree, systemic veins, and obstructed intraatrial channels with stents, can replace or complement conventional balloon angioplasty. It also offers a useful and effective alternative to surgery, when it is impossible or carries a risk.