What is important?

Central venous access is an essential part of perioperative management for infants and children undergoing cardiac surgery for congenital heart disease. In addition, a thorough knowledge of the techniques for cannulation and placement of venous lines from the various percutaneously accessible sites is an important aspect of cardiac catheterization in this patient population. In the first of a series of papers describing the various approaches to venous access, we describe percutaneous cannulation of the subclavian vein. The standard approach, as well as potential difficulties, and how to overcome them, are described, as also the complications associated with this approach.peer-reviewe

Palliative balloon dilation of native coarctation of the aorta in a preterm infant

The role of balloon dilation for native coarctation in neonates is controversial, due to the relatively high recurrence rate. Balloon dilation may however provide adequate palliation in preterm infants, by relieving symptoms and allowing somatic growth until definitive surgical repair can be performed. We report successful balloon angioplasty, on 2 occasions, in a preterm neonate with coarctation of the aorta and associated left ventricular cardiomyopathy.peer-reviewe

Access via the internal jugular vein

Central venous access via the internal jugular vein (IJV) is safe, relatively easy and very commonly used in infants and children undergoing cardiac surgery for congenital heart disease. Because of the wide range of anatomical variations an ultrasound-guided technique is advantageous in many cases, in particular in patients who have had previous punctures or those in whom difficulties are anticipated for various reasons. The right internal jugular vein is the preferred vein for central venous access as it offers straight access to the superior vena cava. The rate of complications - insertion-related as well as long term - are lower compared to the femoral and the subclavian access.peer-reviewe

Access via the femoral vein

Central venous access via the femoral vein (FV) is safe, relatively easy and very usual in infants and children undergoing cardiac surgery for congenital heart disease. It has a low insertion-related complication rate. It is therefore a good choice for short-term central venous lines and a preferred insertion site for less experienced staff. The maintenance-related complications of thrombus formation and infections are higher compared to the internal jugular and the subclavian venous access. Some of these complications are reduced by the use of heparin bonded catheters, routine use of antibiotics, and timely removal of these lines in patients with persistent signs of infection but without another focus being defined.peer-reviewe

Transcription in amphibia in relation to the C-value Paradox : an electron microscopic study

CHAPTER I. The ultrastructure of transcription in cultured cells of T.c. carnifea was compared with, that of cultured cells from X. laevis using the "Miller spreading technique". Primary RHA transcripts of nonribosomal origin, up to 10 mum in length, and arranged in long transcription complexes were observed in T.c. camifex; whereas the maximum length of primary transcripts in S. laevis was about 2 mum. In both cell lines transcription was sparse and predominantly visualised as isolated RNP fibrils. CHAPTER II. Patterns of transcription in liver cells of X, laevis. T.c. carnifex and N. maculosus were compared, using the "Miller" technique. Chromatin had a nucleosomal structure and transcription complexes occurred on beaded chromatin. N. maculosus with the largest C-value (52 pg) synthesised the longest primary transcripts. Transcription complexes of two or more RNP fibrils were rare in the chromatin of these species. The percentages of different types of transcription complex (l RNP fibril, 2 RNP fibrils, 3 or more RNP fibrils) were similar for the three species. CHAPTER III. The ultrastructure of transcription in T.c. carnifex neurula cells was investigated, using the Miller technique. Transcription occurred predominantly in the form of isolated RNP fibrils whose median length was greater than for T.c. carnifex liver cells or cultured cells, in that order. The percentage of transcription complexes of two or more RNP fibrils was greater in T.c. carnifex liver (33.8%) than in T.c. carnifex embryos (17.3%). CHAPTER IV. The Miller technique was used to investigate the ultrastructure of transcription in X. laevis and T.c. carnifex' culture cells treated with cortisol or thyrozine. After cortisol treatment of X. laevis the median lengths of isolated nonrihosomal RNA fibrils, and the terminal fibrils of multifibril complexes, increased twofold, as did the percentage of multifibril transcription completes (from 5.6% to 28.1%), The DNA packing ratio of transcriptionally inactive regions of the chromatin was slightly less than that of untreated cells spread under the same conditions. There was also a decrease in the DNA packing ratio of transcriptionally active regions of the chromatin of treated cells as compared to the value for inactive regions. The results were inconclusive but were not sufficient to eliminate the possibility that an increase in the amount of transcription causes an increase in the size of the nucleus. The results were similarly inconclusive for T.c. carnifex cultured cells treated with cortisol. (Abstract shortened by ProQuest.

Investigating the seasonal variability in source contribution to PM(2.5)and PM(10)using different receptor models during 2013-2016 in Delhi, India

The present work deals with the seasonal variations in the contribution of sources to PM(2.5)and PM(10)in Delhi, India. Samples of PM(2.5)and PM(10)were collected from January 2013 to December 2016 at an urban site of Delhi, India, and analyzed to evaluate their chemical components [organic carbon (OC), elemental carbon (EC), water-soluble inorganic components (WSICs), and major and trace elements]. The average concentrations of PM(2.5)and PM(10)were 131 +/- 79 mu g m(-3)and 238 +/- 106 mu g m(-3), respectively during the entire sampling period. The analyzed and seasonally segregated data sets of both PM(2.5)and PM(10)were used as input in the three different receptor models, i.e., principal component analysis-absolute principal component score (PCA-APCS), UNMIX, and positive matrix factorization (PMF), to achieve conjointly corroborated results. The present study deals with the implementation and comparison of results of three different multivariate receptor models (PCA-APCS, UNMIX, and PMF) on the same data sets that allowed a better understanding of the probable sources of PM(2.5)and PM(10)as well as the comportment of these sources with respect to different seasons. PCA-APCS, UNMIX, and PMF extracted similar sources but in different contributions to PM(2.5)and PM10. All the three models extracted 7 similar sources while mutually confirmed the 4 major sources over Delhi, i.e., secondary aerosols, vehicular emissions, biomass burning, and soil dust, although the contribution of these sources varies seasonally. PCA-APCS and UNMIX analysis identified a less number of sources (besides mixed type) as compared to the PMF, which may cause erroneous interpretation of seasonal implications on source contribution to the PM mass concentration