Use of early fetal tissues obtained from suction termination of pregnancy

Assessment of growth from foot length in Taiwanese neonates

BACKGROUND

Previous studies have demonstrated a positive correlation between foot length (FL) and birth body weight (BBW), birth body length (BBL), and head circumference (HC). However, there is no data on birth FL in Taiwan. The aim of this study was to evaluate FL measurement in Taiwanese neonates as a method of estimating other anthropometric indices.

METHODS

In this retrospective study, we enrolled 256 babies born at our hospital and Kaohsiung Veterans General Hospital from 2003-2005. Medical records were reviewed for sex, BBW, BBL, HC, gestational age, and birth FL. Ill newborns, small-for-gestational-age babies, or those with poor birth footprints were excluded. FL at birth was measured from the center of the back of the heel to the tip of the big toe. Linear regression analysis was used to investigate the relation of FL to BBW and BBL. The intraclass correlation coefficient was used to assess inter-rater reliability.

RESULTS

A total of 256 babies were reviewed. There were 136 male and 120 female neonates. The gestational age was 38.5+/-1.3 (mean+/-standard deviation) weeks, ranging from 35-42 weeks. The BBW was 3137+/-396g. The BBL was 51.1+/-2.1 cm. The HC was 33.5+/-1.7 cm. The FL was 7.4+/-0.46 cm. The regression equation for BBW (y) on FL (x) was as follows: y=486.2+360.4x (p<0.001, r=0.421). The regression equation for BBL (y) on FL (x) was as follows: y=40.1+1.45x (p<0.001, r= 0.305). The regression equation for HC (y) on FL (x) was as follows: y=14.8+2.53x (p<0.001, r=0.423). FL showed excellent reliability, with an intraclass correlation coefficient of 0.965 (p<0.001).

CONCLUSION

Our study demonstrated a significant degree of correlation between FL and BBW, BBL and HC. However, it did not reliably estimate BBW, BBL, or HC-the three anthropometric indices were weakly correlated (r<0.5) with FL.

Foot length, an accurate predictor of nasotracheal tube length in neonates

BACKGROUND

Existing guidelines for optimal positioning of endotracheal tubes in neonates are based on scanty data and relate to measurements that are either non-linear or poorly reproducible in sick infants. Foot length can be measured simply and rapidly and is related to a number of external body measurements.

OBJECTIVES

To evaluate the relation of foot length to nasotracheal length in direct measurements at post mortem examinations, and then compare its clinical relevance with traditional weight based estimates in a randomised controlled trial.

METHODS

The dimensions of the upper airway were measured at autopsy in 39 infants with median (range) postmenstrual age and birth weight of 32 (24-43) weeks and 1630 (640-3530) g. The regression equations with 95% prediction intervals were calculated to estimate the optimal nasotracheal length from foot length. In a randomised trial, 59 neonates were nasally intubated according to foot length and body weight based estimates to assess the achievement of "optimal" and "satisfactory" tube placements.

RESULTS

In the direct measurements of the airway at autopsy, foot length was a better predictor of nasotracheal distances (r(2) = 0.79) than body weight, gestational age, and head circumference (r(2) = 0.67, 0.58, and 0.60 respectively). Measurement of foot length was easy and highly reproducible. In the randomised controlled trial, there were no significant differences between the foot length and body weight based estimates in the rates of optimal (44% v 56%) and satisfactory (83% v 72%) endotracheal tube placements.

CONCLUSIONS

Foot length is a reliable and reproducible predictor of nasotracheal tube length and is at least as accurate as the conventional weight based estimation. This method may be particularly valuable in sick unstable infants.

FA1 immunoreactivity in endocrine tumours and during development of the human fetal pancreas; negative correlation with glucagon expression

Fetal antigen 1 (FA1) is a glycoprotein containing six epidermal growth factor (EGF)-like repeats. It is closely similar to the protein translated from the human delta-like (dlk) cDNA and probably constitutes a proteolytically processed form of dlk. dlk is homologous to the Drosophila homeotic proteins delta and notch and to the murine preadipocyte differentiation factor Pref-1. These proteins participate in determining cell fate choices during differentiation. We now report that FA1 immunoreactivity is present in a number of neuroectodermally derived tumours as well as in pancreatic endocrine tumours. A negative correlation between FA1 and glucagon immunoreactants in these tumours prompted a reexamination of FA1 immunoreactants during fetal pancreatic development. At the earliest stages of development, FA1 was expressed by most of the non-endocrine parenchymal cells and, with ensuing development, gradually disappeared from these cells and became restricted to insulin-producing beta cells. Throughout development FA1 was not detected in endocrine glucagon, somatostatin or pancreatic polypeptide cells. Moreover, developing insulin cells that coexpressed glucagon were negative for FA1. Thus, there was a negative correlation between FA1 and glucagon both in tumours and during development. These results, together with FA1/dlk's similarity with homeotic proteins, point to a role of FA1 in islet cell differentiation.

The developing human biliary system at the porta hepatis level between 11 and 25 weeks of gestation: a way to understanding biliary atresia. Part 2

In biliary atresia, inflammation and destruction of extrahepatic and intrahepatic bile ducts with eventual fibrous obliteration occurs, causing neonatal obstructive jaundice. The onset of the disorder may start antenatally and progress after birth, and the porta hepatis is a constant site of involvement. To date, little is known about the intrauterine development of the bile ducts at the porta hepatis. The present work gives an account of the developmental pattern of bile ducts at the level of the porta hepatis in the normal human fetus from the 11th to the 25th weeks of gestation. It has been observed that the proximal portion of the hilar bile ducts derives from the intrahepatic biliary ductal plate. This occurs following a predictable remodeling sequence by which, from many ductal plate-derived ductules, those destined to become definitive bile ducts are enveloped in a concentric cuff of mesenchyma. Those which are not are deleted. The distal portions of the right and left main hepatic ducts develop from the extrahepatic bile duct. There was no gestational period in which the extrahepatic bile duct and the intrahepatic biliary system were separated. Furthermore, the developing intrahepatic bile ducts maintain luminal continuity with the common bile duct from the start of organogenesis. Biliary atresia may result from: (i) failure to establish a definitive type of bile duct; (ii) leakage of bile from primitive bile ducts resulting in an interstitial inflammatory reaction in the adjacent mesenchyma; and (iii) continuous proliferation of primitive bile ducts at the level of the porta hepatis beyond the 25th week of gestation, as a failed compensatory mechanism.

Extrahepatic biliary atresia: a first-trimester event? Clues from light microscopy and immunohistochemistry

Biliary atresia is an obliterative disorder of the bile ducts, causing obstructive jaundice in neonates. In this study, the developing biliary system of normal human embryos and fetuses was examined and compared with the resected extrahepatic biliary remnants from 205 cases of biliary atresia. At the porta hepatis level, it was found that the primary biliary ductal plate undergoes a specific sequence of remodelling, resulting in the formation of large tubular bile ducts surrounded by thick mesenchyme, between 11 and 13 weeks postfertilisation. These developing ducts are in luminal continuity with the extrahepatic biliary tree throughout gestation. Contrary to long-held belief, no "solid phase" was observed in the development of the extrahepatic bile duct. Examination of the biliary remnants in biliary atresia showed that the porta hepatis is encased in fibrous tissue, and a variable pattern of obliteration of the common hepatic and common bile ducts was observed. Anticytokeratin immunostaining showed similarities between the abnormal ductules within the porta hepatis in biliary atresia, and the developing bile ducts in the first trimester. Biliary atresia may be caused by failure of the remodelling process at the hepatic hilum, with persistence of fetal bile ducts poorly supported by mesenchyme. As bile flow increases perinatally, bile leakage from these abnormal ducts may trigger an intense inflammatory reaction, with subsequent obliteration of the biliary tree.

Human fetal tissue research: practice, prospects, and policy

Tissue from human fetal cadavers has long been used for medical research, experimental therapies, and various other purposes. Research within the last two decades has led to substantial progress in many of these areas, particularly in the application of fetal tissue transplantation to the treatment of human disease. As a result, clinical trials have now been initiated at centers around the world to evaluate the use of human fetal tissue transplantation for the therapy of Parkinson's disease, insulin-dependent diabetes mellitus, and a number of blood, immunological and, metabolic disorders. Laboratory studies suggest a much wider range of disorders may in the future be treatable by transplantation of various types of human fetal tissue. A combination of characteristics renders fetal tissue uniquely valuable for such transplantation, as well as for basic research, the development of vaccines, and a range of other applications. Although substitutes for human fetal tissue are being actively sought, for many of these applications there are at present no satisfactory alternatives. Important issues remain unresolved concerning the procurement, distribution, and use of human fetal cadaver tissue as well as the effects of such use on abortion procedures and incidence. These issues can be addressed by the introduction of appropriate guidelines or legislation, and need not be an impediment to legitimate research and therapeutic use of fetal tissue.