Pattern of the insulin-like growth factor II gene expression during early mouse embryogenesis

The mouse insulin-like growth factor II (IGF-II) gene encodes a polypeptide that plays a role in embryonic growth. We have examined the temporal and spatial pattern of expression of this gene in sections of the mouse conceptus between embryonic days 4.0 and 8.5 by in situ hybridization. Abundant IGF-II transcripts were detected in all the trophectodermal derivatives, after implantation. Labeling was then observed in primitive endoderm, but was transient and disappeared after formation of the yolk sac. Expression was next detected in extraembryonic mesoderm at the early primitive streak stage. Labeling in the embryo proper appeared first at the late primitive streak/neural plate stage in lateral mesoderm and in anterior-proximal cells located between the visceral endoderm and the most cranial region of the embryonic ectoderm. The position of the latter cells suggests that their descendants are likely to participate in the formation of the heart and the epithelium of the ventral and lateral walls of the foregut, where intense labeling was observed at the neural fold stage. Hybridization was also detected in cranial mesenchyme, including neural crest cells. The intensity of hybridization signal increased progressively in paraxial (presomitic and somitic) mesoderm, while declining in the ectoplacental cone. The neuroectoderm and surface ectoderm did not exhibit hybridization at any stage. Immunohistochemical analysis indicated co-localization of IGF-II transcripts, translated pre-pro-IGF-II, and the cognate IGF-II/mannose-6-phosphate receptor. These correlations are consistent with the hypothesis that IGF-II has an autocrine function.

A polymorphic DNA sequence (174-3.7) on chromosome 19 [D19S58]

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Cytotoxic T lymphocytes specific for self tumor immunoglobulin express T cell receptor delta chain

CTL are thought to play a role in the elimination of transformed cells in vivo. The effectiveness of such CTL is in part dependent on recognition of tumor specific antigens. Among the best characterized tumor-specific antigens are the unique or idiotypic determinants on the Ig of B cell lymphomas. Here we describe the generation and properties of human CTL specific for the idiotype on autologous B cell tumors. These cells are CD3+,CD4-,CD8- and express the delta chain of the TCR. Such cells may prove useful in tumor-specific adoptive therapy.

A Bgl II polymorphism detected by LDR152 [D19S19]

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A new probe for the diagnosis of myotonic muscular dystrophy

Myotonic muscular dystrophy (DM) is the most common muscular dystrophy, affecting adults as well as children. It is inherited as an autosomal dominant trait and is characterized by variable expressivity and late age-of-onset. Linkage studies have established the locus on chromosome 19. In order to identify tightly linked probes for diagnosis as well as to define in detail the DM gene region, chromosome 19 libraries were constructed and screened for restriction fragment length polymorphisms tightly linked to DM. A genomic clone, LDR152 (D19S19), was isolated that is tightly linked to DM; recombination fraction = 0.0 (95% confidence limits 0.0-0.03); lod score, 15.4.

Hemifacial spasm due to cerebellopontine angle lipoma: case report

We report the unique case of a patient with hemifacial spasm caused by a lipoma of the cerebellopontine angle, which was identified preoperatively by CT and MRI. Surgery resulted in complete resolution of facial spasm.

Persistently elevated AFP and AChE in amniotic fluid from a normal fetus following demise of its twin

Intrauterine fetal demise (IUFD) in one of twins at 12 weeks of gestation was accompanied by markedly elevated maternal serum alpha-fetoprotein (AFP) at 17 and 18 weeks. Amniotic fluid AFP from the healthy surviving twin's sac at 18.5 and 23 weeks was also greatly increased along with a positive acetylcholinesterase (AChE) band. Persistently elevated AFP and positive AChE so long after fetal demise--6.5 and 11 weeks post IUFD--has not, to our knowledge, been previously described. In similar cases, high level ultrasound and careful placental examination at birth should be utilized to search for fetal abnormalities or multiple pregnancy with IUFD.

False-positive amniotic fluid acetylcholinesterase results: the need for a multifacet approach to the prenatal diagnosis of neural tube defects

Two cases are presented with false-positive amniotic fluid alpha-fetoprotein and acetylcholinesterase results for the prenatal diagnosis of neural tube defects. Stage II ultrasound revealed no lesions of the fetal spine in both cases. The alpha-fetoprotein and acetylcholinesterase results returned to normal on subsequent taps. Both pregnancies resulted in normal outcomes. A protocol is presented for managing pregnancies with abnormal alpha-fetoprotein and acetylcholinesterase results.

Beta-glucuronidase deficiency. A heterogeneous mucopolysaccharidosis

We studied two cases of beta-glucuronidase deficiency. One patient's disease was present at birth and the other patient's disease appeared in early childhood. The symptoms observed in both patients, although of differing severity, included peculiar facies, cloudy cornea, hepatosplenomegaly, hernia, kyphosis, recurrent infections, short stature, and developmental delay, as well as increased excretion of urinary chondroitin sulfate A/C and decreased levels of beta-glucuronidase activity. We reviewed all of the reported cases and examined the biochemical and clinical heterogeneity observed in this disorder.

Early precursors of site-specific cancers in college men and women

Physical and social characteristics recorded at college physical examination and reported in subsequent questionnaires to alumni in 1962 or 1966 by 50,000 former students from Harvard University and the University of Pennsylvania were reviewed for their relationship to major site-specific cancer occurrence. The records of 1,359 subjects who died with a major site-specific cancer in a 16- to 50-year follow-up period and of 672 subjects who reported such a cancer by mail questionnaire in 1976 or 1977 were compared with those of 8,084 matched classmates who were known to be alive and free of cancer at the time subjects with cancer had died or had been diagnosed. Cigarette smoking, as reported both in student years and years as alumni, predicted increased risk for cancers of the respiratory tract, pancreas, and bladder. Student coffee consumption was associated with elevated risk for leukemia, but it was unrelated to cancers of the pancreas and bladder. Male students with a record of proteinuria at college physical examination experienced increased risk of kidney cancer, and those with a history of tonsillectomy experienced increased risk of prostate cancer. Students who at college entrance reported occasional vague abdominal pain were at elevated risk for pancreatic and colorectal cancers in later years. Increased body weight during college was associated with increased risks of kidney and bladder cancers, whereas for alumni this index was associated only with kidney cancer. Increased weight-for-height during college (but not in 1962 or 1966) predicted increased occurrence of female breast cancer. Jewish students experienced elevated risk for subsequent cancers of the female breast, colon, and combined colorectum. These and other findings are presented as clues deserving further exploration for any etiologic significance that they may hold for the cancer sites studied.

Early precursors of urogenital cancers in former college men

Physical and social characteristics recorded at college physical examination or reported at subsequent alumni questionnaire in 1962 or 1966 by 47,271 male former students from Harvard University and the University of Pennsylvania were reviewed for their relationship to risk for cancers of the kidney, bladder, prostate and testis. The records of 213 subjects who died with 1 of these cancers in a 16-50 year followup period and of 280 subjects who reported such a cancer by mail questionnaire in 1976 or 1977 were compared with those of 1,972 matched classmates who were known to be alive and cancer-free at the time subjects with cancer had died or were diagnosed. Students with a record of proteinuria at college physical examination experienced increased risk of kidney cancer. Higher levels of body weight during college were associated with elevated risks of kidney and bladder cancers; however, increased weight in 1962/1966 related only to kidney cancer. A history of cigarette smoking as reported by questionnaire in 1962/1966 predicted increased occurrence of bladder cancer. Students with a history of tonsillectomy at college entrance experienced increased risk of prostate cancer, and those who reported cancer history in 1 or both parents were at increased risk for testicular cancer. These and other findings are presented as clues deserving further exploration for any etiological significance they may hold for the cancer sites studied.

Solubilization of the carcinogen nickel subsulfide and its interaction with deoxyribonucleic acid and protein

Significant concentrations (1-10 mM) of nickel(II) were found in solution after incubation of the potent carcinogen nickel subsulfide in 0.05 M Tris-HCl, pH 7.4, solutions containing DNA, rat liver microsomes, and NADPH. The presence of NADPH decreased the rate of solubilization of nickel subsulfide. The solubilized nickel exhibited electronic absorption spectra and magnetic moments characteristic of octahedral nickel(II). The solubilized nickel(II) bound to DNA with an apparent equilibrium constant of 730 M-1 and with a saturation binding value of one nickel per 2.4 nucleotides. Microsomes lowered the saturation binding of nickel to DNA but dramatically increased the amount of nickel-DNA complex stable to precipitation with salt and poly-(ethylene glycol). The amount of protein associated with DNA precipitated from protein-extracted solutions correlated with the amount of nickel bound to DNA. These results suggest that microsomes mediate the binding of nickel to DNA by forming a stable ternary protein-nickel(II)-DNA complex.

Purification and chemical characterization of human acidic alpha-D-mannosidase

The acidic alpha-D-mannosidase (EC 3.2.1.24) has been purified from human placentae. Milligram quantities of the enzyme were obtained from several placentae, using a step-wise purification procedure which includes Con A-Sepharose treatment, acetone precipitation, heat treatment, DEAE-cellulose column chromatography and preparative disc electrophoresis. A high degree of purity of the purified enzyme was demonstrated by acrylamide gel electrophoresis, isoelectric focusing, and sedimentation equilibrium centrifugation. Immunological homogeneity of the preparation was demonstrated by a single precipitin line between the antiserum and purified, or partially purified enzyme preparation. The amino acid and carbohydrate composition of the enzyme was determined. The enzyme was found to be a glycoprotein containing 13.5% carbohydrate. The molecular weight of the enzyme was estimated at 205,000 +/- 18,400.

Structural comparison of hexosaminidases in primates

1. beta-Hexosaminidase (hex) structure was compared in various primates, using thin-layer isoelectric focusing on polyacrylamide gels and quantitative microcomplement fixation. 2. Isoelectric focusing revealed no intraspecies differences and similar interspecies patterns. 3. Hex A and B are evolving at a moderate, but equal, rate and in a manner consistent with accepted phylogenetic patterns. 4. Quantitative microcomplement fixation revealed a closer homology between human hex A and chimpanzee A or human hex B and chimpanzee hex B than between human hex A and human hex B.

The subunits of human hexosaminidase A

Previous studies of the subunit structure of hexosaminidase gave ambiguous results, but suggested that the enzyme was composed of six equally sized subunits. Dissociation of hexosaminidase A with p-chloromercuribenzoate produces an alkylated fragment with mol.wt. approx. 50000, which is converted into hexosaminidase S by treatment with dithiothreitol. Treatment of native hexosaminidase A with sodium dodecylsulphate results in the formation of a large and a small fragment. However, although the native enzyme has a sedimentation coefficient of 5.8S, dissociation by S-carboxymethylation and maleic anhydride treatment results in subunits exhibiting a single schlieren boundary on analytical ultracentrifugation with a sedimentation coefficient of 2.18S. These results indicate that the enzyme is composed of four subunits, each with molwt. approx. 25000-27000. The mol.wt. of the native enzymes is calculated to be approx. 110000. Our data are consistent with the subunit structures of hexosaminidases A, B and S as being alpha2beta2, beta4 and alpha4 respectively.

Purification and chemical characterization of human hexosaminidases A and B

N-Acetyl-beta-hexosaminidases A and B were purified to homogeneity from human placenta. In the initial step of purification, the enzymes were adsorbed on concanavalin A-Sepharose 4B and eluted from the column with alpha-methyl D-mannosides. Subsequent purification steps included DEAE-cellulose column chromatography, QAE-Sephadex [diethyl-(2-hydroxypropyl)aminoethyl-Sephadex] column chromatography, Sephadex G-200 gel filtration and preparative disc polyacrylamide-gel electrophoresis, followed by another QAE-Sephadex chromatography for the hexosaminidase A preparation, and DEAE-cellulose column chromatography, calcium phosphate gel chromatography, Sephadex G-200 gel filtration, QAE-Sephadex chromatography and CM-cellulose chromatography for the hexosaminidase B preparation. The purified preparations, particularly hexosaminidase A, had significantly higher specific enzyme activities than previously reported. The preparations moved on polyacrylamide-gel electrophoresis as single protein bands, which also stained for enzyme activity. Sedimentation-equilibrium centrifugation indicated homogenous dispersion of the enzymes, and the molecular weight was estimated as about 110000 for both enzymes. Complete amino acid and carbohydrate compositions of the two isoenzymes were determined, and, in contrast with previous suggestions, no sialic acid was found in the enzymes.

Propranolol treatment of essential tremor

Propranolol treatment of patients with essential tremor, selected for chronic, nonresting tremor of hands and head causing functional impairment, benefited only one of nine patients during a double-blind study (320 mg per day). No serious cardiorespiratory complications occurred in this screened patient group, but an elderly man became agitated and depressed. We conclude that propranolol does not benefit all patients with essential tremor and that this disorder may be caused by several biochemical mechanisms.