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Nonimmune hydrops fetalis.

Nonimmune hydrops fetalis (NIHF) is a term that defines an edematous fetus that does not have erythroblastosis fetalis from isoimmunization. All of the other reasons that a fetus develops NIHF are included in this category. The causes of NIHF range from diseases to structural anomalies to genetic abnormalities. The mere presence of NIHF is a poor prognostic indicator, even with the etiology unknown. Some causes of NIHF are treatable with intrauterine therapies. These currently include cordocentesis to administer intrauterine transfusions or medications and fetal surgery. Prenatal testing to establish an etiology or follow the progress of the fetus is extensive, expensive, and stressful. The mortality rate remains high. Education, counseling, and support of the patient and family are the work of the prenatal period. Delivery room management of the infant with NIHF requires a resuscitation team with a specific plan of care to maximize chances of survival.

Cordocentesis↗

Rho(D) immunoglobulin (RhoGAM): how it came into being.

The story of Rho(D) immunoglobulin (RhoGAM) begins in 1909 with Theobald Smith, Fabyan Professor of Comparative Pathology at Harvard, and ends in the 1960s with completion of the clinical trials. Important in the development of RhoGAM were the search for a safe diphtheria vaccine, an interest in butterfly mimicry, the discovery of the Rhesus factor, and the contribution of Sing Sing prison inmates--seemingly unrelated occurrences. But, when all were combined, the riddle of erythroblastosis fetalis was solved.

Diphtheria Toxoid↗

Dr. James A. Wolff. III. First pediatric hematologist at Babies Hospital.

Since there was no position for a full-time pediatric hematologist, Dr. Wolff practiced general pediatrics for 10 years while he volunteered as director of the hematology clinic at the Babies Hospital. He was appointed full-time Director of Pediatric Hematology in 1959. His early clinical studies were concerned with treatment of erythroblastosis fetalis and use of frequent transfusions and desferroxamine in children with thalassemia. The combined tumor clinic at the Babies Hospital, established in 1952, was one of the first to use the multidisciplinary approach to treatment of the child with cancer. In 1957, the Children's Leukemia Group A, later called the Children's Cancer Study Group, was established by Dr. Joseph Burchenal. Dr. Wolff was one of the first members. This group led to the establishment of various national intergroup committees for clinical study of cancers in children. In 1954, Farber began to use dactinomycin for treatment of Wilms' tumor. At first this drug was used only for treatment of metastatic tumors, but later it was also used to prevent metastases. Subsequently, other childhood tumors were found to be amenable to chemotherapy.

Hematology↗

The structure and function of the epidermal growth factor receptor studied by using antisynthetic peptide antibodies.

The human epidermal growth factor receptor has been purified and partial amino acid sequence obtained. A synthetic oligonucleotide was used to select complementary DNA clones from placental and A431 clone banks. The nucleotide sequence of a 5.8 kilobase transcript was determined and used to predict the total amino acid sequence of the receptor. We have predicted a model for the receptor which has an external ligand binding domain of 621 amino acids, a transmembrane region of 23 amino acids, and a cytoplasmic domain of 542 amino acids having protein tyrosine kinase activity. The kinase autophosphorylation sites have been mapped onto the primary amino acid sequence. Analysis of protein sequence databases have shown that the erb-B oncogene of avian erythroblastosis virus has acquired part of the avian EGF receptor gene. The hypothesis has been proposed that transformation by this virus is the result of expression of a truncated EGF receptor which lacks the majority of the EGF binding domain and delivers a continuous proliferation signal to transformed cells. We describe here the production of polyclonal and monoclonal antibodies to selected synthetic peptides from the EGF receptor and v-erb B sequences. Antisera to sequences encompassing the three major sites of autophosphorylation and the putative ATP binding site all recognize the native EGF receptor molecule. We have used these reagents to test our model of EGF receptor structure and v-erb B function.

Amino Acid Sequence↗

Derivation of mouse sarcoma virus (Kirsten) by acquisition of genes from heterologous host.

The technique of virus RNA-cellular DNA hybridization in solution with DNA excess was used to compared the nucleotide sequences of the 70 S RNA genome of the Kirsten mouse sarcoma virus (Ki-MSV) with that of mouse erythroblastosis virus (MEV) which gave rise to Ki-MSV after in vivo propagation in rat. It is suggested that a loss of about 30% of the genomic sequences of MEV with a concomitant gain of roughly equal amounts of rat-specific sequences in a genetically stable recombinant state led to the formation of Ki-MSV.

Animals↗

The viral envelope is a major determinant for the induction of lymphoid and myeloid tumours by avian leukosis virus subgroups A and J, respectively.

Among the six envelope subgroups of avian leukosis virus (ALV) that infect chickens, subgroups A (ALV-A) and J (ALV-J) are the most pathogenic and widespread among commercial chicken populations. While ALV-A is predominantly associated with lymphoid leukosis (LL) and less frequently with erythroblastosis (EB), ALV-J mainly induces tumours of the myeloid lineage. In order to examine the basis for the lineage specificity of tumour induction by these two ALV subgroups, we constructed two chimeric viruses by substituting the env genes into the reciprocal proviral clones. The chimeric HPRS-103(A) virus carrying the subgroup A env gene is identical to ALV-J prototype virus HPRS-103 except for the env gene, and the chimeric RCAS(J) virus carrying the subgroup J env gene is identical to the parent replication-competent ALV-A vector RCAS except for the env gene. In experimentally inoculated chickens, HPRS-103(A) virus induced LL and EB similar to ALV-A isolates such as RAV-1, while RCAS(J) virus induced myeloid leukosis (ML) and EB, similar to ALV-J, suggesting that the env gene is the major determinant for the lineage-specific oncogenicity. There were genetic differences in susceptibility to tumour induction between line 0 and line 15(I) chickens, indicating that in addition to the env gene, other viral or host factors could also serve as determinants for oncogenicity. Induction of both LL and ML by the two chimeric viruses occurred through the activation of c-myc, while the EB tumours were induced by activation of the c-erbB oncogene.

Alpharetrovirus↗

E (XSR) element contributes to the oncogenicity of Avian leukosis virus (subgroup J).

Among the six subgroups of Avian leukosis virus (ALV) that infect chickens, subgroup J (ALV-J) was isolated from meat-type chickens where it predominantly induces myeloid leukosis (ML) and erythroblastosis (EB). The sequence of HPRS-103, the ALV-J prototype virus, shows several distinct features, one of which is the presence of a distinct hairpin stem-loop structure called the E (also called XSR) element in the 3' untranslated region. In order to determine the role of the E element in ALV-induced pathogenicity, a comparison was made of the oncogenicity of viruses derived from the provirus clones of parental and E element-deleted HPRS-103 viruses in two genetically distinct lines of birds. In line 15I birds, deletion of the E element had profound effects on virus replication in vivo, as only 55 % of birds showed evidence of infection, compared with 100 % infection by the parental virus. Furthermore, none of the line 15I birds infected with this virus developed tumours, indicating that the E element does contribute to the oncogenicity of the virus. On the other hand, deletion of the E element had only a marginal effect on the incidence of tumours in line 0 birds. These results indicate that, although the E element per se is not absolutely essential for tumour induction by this subgroup of viruses, it does contribute to oncogenicity in certain genetic lines of chicken.

3' Untranslated Regions↗

Temperature-sensitive v-sea transformed erythroblasts: a model system to study gene expression during erythroid differentiation.

The isolation and characterization of a temperature-sensitive mutant (ts1 S13) of the avian erythroblastosis virus, S13, is described. The temperature-sensitive lesion in ts1 S13 was identified as affecting the tyrosine kinase activity but not the plasma membrane localization of the ts1 S13 v-sea gene product. Erythroblasts transformed by ts1 S13 can be induced to synchronously differentiate into erythrocytes in an erythropoietin (EPO)-dependent fashion. Analysis of erythrocyte-specific gene expression in ts1 S13 erythroblasts reveals that the transformed, self-renewing erythroblasts obtained at permissive temperature already express all erythrocyte genes tested for, although at a low level. Upon differentiation induction, expression of erythrocyte-specific genes is not coordinately regulated but rather involves complex regulatory mechanisms that appear to be specific for the individual genes.

Alpharetrovirus↗

Phosphorylation of the v-erbA protein is required for its function as an oncogene.

The v-erbA oncogene of avian erythroblastosis virus (AEV) encodes a ligand-independent mutated version of the chicken c-erbA alpha-encoded thyroid hormone receptor. The v-erbA gene product, a 75-kD gag/v-erbA fusion protein, is phosphorylated on Ser-16/17 of its v-erbA-encoded domain, and phosphorylation at this site is increased in vivo after activation of either the PKA or PKC signal transduction pathways. To test the hypothesis that phosphorylation of Ser-16/17 regulates gag/v-erbA protein function, mutant proteins in which Ser-16/17 had been changed to alanine or threonine residues were analyzed for their ability to inhibit erythroid differentiation of ts v-erbB or ts v-sea-transformed erythroblasts at nonpermissive temperature. Conversion of Ser-16/17 into alanine, although not affecting nuclear localization or DNA binding of the gag/erbA protein, prevented phosphorylation of the v-erbA-encoded domain of the protein both in unstimulated cells or after stimulation by PKA and PKC activators. The nonphosphorylatable AA-gag/v-erbA protein proved unable to inhibit temperature-induced differentiation of ts v-erbB and ts v-sea-transformed erythroblasts and to block expression of the erythrocyte-specific genes band 3 and carbonic anhydrase II. Back mutation of these alanine residues to serine resulted in the recovery of both normal phosphorylation levels and wild-type biological activity. In contrast, substitution of Ser-16/17 for threonine, which preserved phosphorylation in unstimulated cells but not PKA- and PKC-enhanced phosphorylation, resulted in a partially active gag/v-erbA protein. These results, together with the fact that the protein kinase inhibitor H7 resulted in both a dose-dependent inhibition of gag/v-erbA protein phosphorylation and the induction of terminal differentiation of AEV-transformed erythroblasts show that phosphorylation of gag/v-erbA protein is required for full biological activity. These results support the hypothesis that phosphorylation of the gag/v-erbA protein is important for transcriptional repression of at least some of its target genes in erythroid cells.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

Expression and characterization of kinase-active v-erbB protein using a baculovirus vector system.

The v-erbB gene is an oncogene of the avian erythroblastosis virus encoding a protein that is a truncated version of the epidermal growth factor receptor. The v-erbB protein was expressed alone or as polyhedrin-erbB fusion proteins using the Bombyx mori nuclear polyhedrosis virus vector. The expression level of the fusion protein whose polyhedrin portion consisted of only 8 amino-terminal amino acids was more than ten times higher than that of the non-fusion protein. Studies with tunicamycin showed that the recombinant v-erbB proteins were glycosylated. The recombinant protein autophosphorylated tyrosine residues, and phosphorylated a synthetic tyrosine-containing peptide and lipocortin I. These observations indicate that functional v-erbB protein can be expressed in silkworm-derived cells, and furthermore, that this system can be used for large-scale production.

Amino Acid Sequence↗

Expression of embryonic haemoglobin in tsAEV-transformed embryonic erythroid cells during temperature-induced differentiation.

Cells prepared from 1-day-old chick blastoderms were infected with a temperature-sensitive mutant of avian erythroblastosis virus (tsAEV). Clonal strains of transformed erythroblasts were isolated from the infected blastoderm cells. By shift to the nonpermissive temperature, these cells could be induced to differentiate into erythrocyte-like cells which expressed embryonic haemoglobins. Embryonic haemoglobins could not be detected in tsAEV-transformed erythroblasts from adult bone marrow when induced to differentiate under the same conditions. In contrast to normal primitive erythrocytes, tsAEV-infected embryonic erythroblasts differentiated in vitro expressed also adult haemoglobin. These results suggest an influence of the haematopoietic environment on the switch from embryonic to adult erythrocytes.

Alpharetrovirus↗

Antibodies to the ATP-binding site of the human epidermal growth factor (EGF) receptor as specific inhibitors of EGF-stimulated protein-tyrosine kinase activity.

A region of the primary amino acid sequence of the epidermal growth factor receptor (EGF) protein-tyrosine kinase, which is involved in ATP binding, was identified using chemical modification and immunological techniques. EGF receptor was 14C-labelled with the ATP analogue 5'-p-fluorosulphonylbenzoyladenosine and from a tryptic digest a single radiolabelled peptide was isolated. The amino acid sequence was determined to be residues 716-724 and hence lysine residue 721 is located within the ATP-binding site. Antisera were elicited in rabbits to a synthetic peptide identical to residues 716-727 of the EGF receptor and the homologous sequence in v-erb B transforming protein from avian erythroblastosis virus. The affinity-purified antibodies precipitated human ECF receptor from A431 cells and placenta, and the v-erb B protein from erythroblasts. The antibodies inhibited EGF-stimulated receptor protein-tyrosine kinase autophosphorylation and phosphorylation of an exogenous peptide substrate containing tyrosine. The antibodies did not immunoprecipitate the transforming proteins pp60v-src or P120gag-abl or cAMP-dependent protein kinase, proteins which have homologous but not identical sequences surrounding the lysine residue within the ATP-binding site, nor did they react with the platelet-derived growth factor receptor. The antibodies had no effect on the kinase activity of purified v-abl protein in solution. The antibodies may therefore be a specific inhibitor of the tyrosine kinase of the EGF receptor.

Adenosine↗

Structure and expression of the chicken epidermal growth factor receptor gene locus.

Similarity between the carboxyl-terminal portion of the human epidermal growth factor (EGF) receptor and the deduced protein sequence of the chicken-derived oncogene v-erbB, of avian erythroblastosis virus strain H, has suggested that the chicken cellular erbB locus, c-erbB, might be part of a longer EGF-receptor gene in the chicken, whose entire coding capacity remained to be defined. The c-erbB locus spans more than 20 X 10(3) base pairs (20 kbp) of DNA and contains at least 1.8 kbp homologous to the v-erbB oncogene. We show here that human EGF receptor cDNA and chicken genomic DNA share homology not only within the c-erbB locus but also within a 25.1-kbp DNA region situated 5' to this locus. The 3' region of the EGF receptor overlaps, in sequence homology, the c-erbB locus. The EGF receptor/c-erbB locus in chicken generates six related but distinctly different mRNAs of sizes 12, 9, 5, 3.6, 3.2 and 2.6 kb. The transcripts of 12, 9, and 3.6 kb contain sequences coding for both the extracellular EGF-binding domain of the receptor and the intracellular tyrosine kinase domain. The 12-kb and 9-kb transcripts, which have already been shown to contain the sequences coding for the v-erbB, were found to possess, in addition, sequences that encode the entire chicken EGF receptor. The 3.2-kb and 2.6-kb mRNAs are homologous only to the 5' portion of the EGF receptor gene. These results therefore indicate that the c-erbB locus, initially defined by homology to the viral transforming gene, corresponds to the 3' region of the EGF receptor gene in the chicken genome. The multiple, related, chicken EGF receptor RNA transcripts reported here are reminiscent of the various human EGF receptor RNA transcripts observed in normal and transformed cells.

Alpharetrovirus↗

Alternative initiation of transcription of the human presenilin 1 gene in SH-SY5Y and SK-N-SH cells. The role of Ets factors in the regulation of presenilin 1.

We have identified DNA sequences required for the expression of the presenilin 1 (PS1) gene. A promoter region has been mapped in SK-N-SH cells and includes sequences between -118 and +178 flanking the major initiation site (+1). The PS1 gene is also efficiently transcribed in the SH-SY5Y subclone of SK-N-SH cells. However the promoter appears to be utilized in alternative ways in both cell types. Sequences both upstream as well as downstream from the initiation site mapped in SK-N-SH cells were shown by 5'- and 3'-deletion analysis to play a crucial role in both cell lines. However, in SH-SY5Y cells either upstream or downstream sequences are sufficient to direct transcription, whereas in SK-N-SH cells 5'-deletions past the +1 site eliminate over 95% of transcription. Several Ets motifs (GGAA) as well as Sp1 motifs [(G/T)GGCGGRRY] are juxtaposed both upstream and downstream from +1. To understand how the promoter may be utilized alternatively in different cell types we have examined the effect of point mutations in these elements. Altering an Ets motif at -10 eliminates 80% of transcription in SK-N-SH cells whereas the same mutation has only a minor effect in SH-SY5Y cells. Conversely, mutation of the Ets element at +90, which eliminates 70% of transcription in SH-SY5Y cells, has a lesser effect in SK-N-SH cells. In both cell types a promoter including mutations at both -10 and +90 sites loses over 90% transcription activity indicating the crucial importance of these two Ets motifs. The effect of Sp1 mutations appears to be similar in both cell types. Hence the differential expression in each cell type may be at least partially determined by Ets factors and the -10/+90 sites. We have identified several Ets factors that recognize specifically the -10 Ets motif by the yeast one-hybrid selection including avian erythroblastosis virus E26 oncogene homologue 2, Ets-like gene 1, Ets translocation variant 1 and Ets related molecule (ERM). We show here that ERM specifically recognizes Ets motifs on the PS1 promoter located at -10 as well as downstream at +90, +129 and +165 and activates PS1 transcription with promoter fragments containing or not the -10 Ets site.

Amino Acid Motifs↗

Neuroblastoma in situ.

Two cases of neuroblastoma in situ incidentally found in young infants at autopsy are reported. One was an 8-day-old female infant of large for dates clinically diagnosed as fetal erythroblastosis. Histologically, several foci of tumor were scattered within the medulla of the left adrenal gland. This case was thought to be multiple neuroblastoma in situ. The other was a 34-day-old male infant who was born premature and associated with patent ductus arteriosus (PDA). Grossly, a solitary small nodule was seen in the right adrenal gland. Microscopically, the lesion was located within the medulla. In both cases, the tumor was composed of lymphocyte-like small and dark cells with rosette formations. Local infiltrations were observed, but not metastasis. The review of 611 autopsy cases of neuroblastoma reported in the Annual of the Pathological Autopsy Cases in Japan, vol. 11 (1968) to vol. 20 (1977)2 revealed 7 cases of neuroblastoma in situ including one of our cases. The peculiar features of neuroblastoma were described.

Adrenal Gland Neoplasms↗

Etiological factors in cerebral palsy: an historical review.

The etiological factors in 1503 patients with cerebral palsy seen since 1947 are listed. Prematurity was the most prominent factor, being present in 27.8 per cent of cases. 38.5 per cent of the causes were prenatal in origin, 46.3 per cent natal, and 15.2 per cent postnatal. Since 1947, the number of patients seen rose to a maximum in the 1950s and has fallen since. A steadily increasing percentage of the patient population has been children with spasticity, especially paraplegia and quadriplegia. Although small, the atonic group has shown a marked increase, from 0.8 per cent in the 1950s to 3.4 per cent in the 1970s. There has been a dramatic decrease in the incidence of athetosis, from 38 per cent to about 3 per cent, and a slight decrease in the rigidities. The incidence of some of the etiological factors has increased, such as hydrocephalus, prematurity, trauma and multiple birth. There has been a striking decrease in the incidence of erythroblastosis as a factor, which dropped to nil in the 1970s. There have been lesser decreases in encephalitis, dystocia and idiopathic factors.

Birth Injuries↗

The significance of anti-c alloimmunization in pregnancy.

In an 8-year period, 177 of 280,000 pregnancies were complicated by maternal anti-c alloimmunization. Although there was one neonatal death associated with anti-c haemolytic disease of the newborn, only two infants were severely anaemic at birth. A total of 11 babies required exchange transfusion, but nine of these developed hyperbilirubinaemia alone. The remaining c positive infants were either unaffected or only mildly affected by erythroblastosis fetalis. A strategy for management of these pregnancies is outlined, and proposed methods of prevention and serological control are discussed.

Blood Group Incompatibility↗

Serum ferritin and cobalamin in growth retarded fetuses.

OBJECTIVE: To examine fetal and maternal serum cobalamin and ferritin concentrations in pregnancies complicated by fetal growth retardation. SETTING: Harris Birthright Research Centre for Fetal Medicine, King's College Hospital Medical School, London. DESIGN: Cross sectional study. SUBJECTS: Fetal blood samples obtained by cordocentesis from 20 growth retarded fetuses at 26 to 36 weeks of gestation. Maternal venous blood was also collected and serum ferritin and cobalamin concentrations were measured by radio-immunoassay in the fetal and maternal samples. RESULTS: In the growth retarded group, the mean fetal serum concentration of cobalamin was higher than the normal mean for gestation (t = 3.27, P < 0.01), and this increase was significantly associated with fetal acidaemia (r = -0.686, P < 0.001) and erythroblastosis (r = 0.731, P < 0.001). In contrast, the fetal to maternal ferritin ratio was significantly reduced; there was a nonsignificant decrease in fetal serum and an increase in maternal serum ferritin concentration. There was an association between fetal serum ferritin concentration and erythrocyte count (r = -0.612, P < 0.01). CONCLUSIONS: In placental insufficiency, as in postnatal starvation and Kwashiorkor syndrome, uptake and storage of cobalamin by the fetal liver may be impaired. The decrease in fetal to maternal ratio of ferritin could be the consequence of impaired placental perfusion.

Acidosis↗