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Prenatal exposure to diethylstilbestrol (DES) is associated with reproductive tract abnormalities, subfertility and neoplasia in experimental animals and humans. Studies using experimental animals suggest that the carcinogenic effects of DES may be transmitted to succeeding generations. To further evaluate this possibility and to determine if there is a sensitive window of exposure, outbred CD-1 mice were treated with DES during three developmental stages: group 1 was treated on days 9-16 of gestation (2.5, 5 or 10 microg/kg maternal body weight) during major organogenesis; group II was treated once on day 18 of gestation (1000 microg/kg maternal body weight) just prior to birth; and group III was treated on days 1-5 of neonatal life (0.002 microg/pup/day). DES-exposed female mice (F(1)) were raised to maturity and bred to control males to generate DES-lineage (F(2)) descendants. The F(2) males obtained from these matings are the subjects of this report; results in F(2) females have been reported previously [Newbold et al. (1998) CARCINOGENESIS:, 19, 1655-1663]. Reproductive performance of F(2) males when bred to control females was not different from control males. However, in DES F(2) males killed at 17-24 months, an increased incidence of proliferative lesions of the rete testis and tumors of the reproductive tract was observed. Since these increases were seen in all DES treatment groups, all exposure periods were considered susceptible to perturbation by DES. These data suggest that, while fertility of the DES F(2) mice appeared unaltered, increased susceptibility for tumors is transmitted from the DES 'grandmothers' to subsequent generations.

We have used in situ hybridization to determine the regional distribution of mRNA encoding the neurotensin/neuromedin N (NT/N) precursor in the forebrain of the adult male rat. Cells containing NT/N mRNA are widely distributed in the forebrain. These areas include the septum, bed nucleus of the stria terminalis, preoptic area, hypothalamus, amygdala, accumbens nucleus, caudate-putamen, and piriform and retrosplenial cortex. In general, the regional distribution of NT/N mRNA corresponds to the previously determined distribution of neurotensin-immunoreactive cell bodies; however, several notable exceptions were observed. The most striking difference occurs specifically in the CA1 region of the hippocampus, where intense labeling is associated with the pyramidal cell layer despite the reported absence of neurotensin-immunoreactive cells in this region. Analysis of microdissected tissue by S1 nuclease protection assay confirmed the abundance of authentic NT/N mRNA in CA1. A second major discrepancy between NT/N mRNA abundance and neurotensin-immunoreactivity occurs in the intensely labeled subiculum, a region that contains only scattered neurotensin-immunoreactive cells in the adult. These results suggest that, in specific regions of the forebrain, NT/N precursor is processed to yield products other than neurotensin. In addition, these results provide an anatomical basis for studying the physiological regulation of NT/N mRNA levels in the forebrain.

Renal lithiasis, pyelonephritis, and glomerulonephritis were common in our colony of Brazilian phenotype squirrel monkeys (Saimiri sciureus), with glomerulonephritis being a major cause of mortality in adult animals. Squirrel monkey glomerulonephritis was divided into four major classifications, based on light and electron microscopy, similar to those of man: focal sclerosing glomerulonephritis, membranoproliferative glomerulonephritis, membranous glomerulonephritis, and a combination of membranoproliferative and membranous glomerulonephritis.

Prenatal exposure to diethylstilbestrol (DES) has been associated with the subsequent development of reproductive tract abnormalities, including poor reproductive outcome and neoplasia, in experimental animals and humans. Experimental animal studies with chemical carcinogens have raised the possibility that adverse effects of DES may be transmitted to succeeding generations. To evaluate this possibility and to determine if there is a sensitive window of developmental exposure, outbred CD-1 mice were treated with DES during three stages of development: group 1 was treated on days 9-16 of gestation (2.5, 5 or 10 μg/kg maternal body wt), the time of major organogenesis; group II was treated once on day 18 of gestation (1000 μg/kg maternal body wt) just prior to birth; group III was treated on days 1-5 of neonatal life (0.002 μg/pup/day). Female mice (F1) in each group were raised to sexual maturity and bred to control males. As previously reported, fertility of the F1 DES-exposed females was decreased in all groups. Female offspring (DES lineage or F2) from these matings were raised to maturity and housed with control males for 20 weeks. The fertility of these DES lineage female mice was not affected by DES exposure of their 'grandmothers'. DES lineage mice were killed at 17-19 and 22-24 months of age. An increased incidence of malignant reproductive tract tumors, including uterine adenocarcinoma, was seen in DES lineage mice but not in corresponding controls; the range and prevalence of tumors increased with age. Because uterine adenocarcinomas were seen in all three DES groups, all developmental exposure periods were considered susceptible to the adverse effects of DES. These data suggest that the reduced fertility observed in the DES F1 female mice was not transmitted to their descendants; however, increased susceptibility to tumor formation is apparently transmitted to subsequent generations.

Aldehyde reductase [EC 1.1.1.2] and aldose reductase [EC 1.1.1.21] are monomeric NADPH-dependent oxidoreductases having wide substrate specificities for carbonyl compounds. These enzymes are implicated in the development of diabetic complications by catalyzing the reduction of glucose to sorbitol. Enzyme inhibition as a direct pharmacokinetic approach to the prevention of diabetic complications resulting from the hyperglycemia of diabetes has not been effective because of nonspecificity of the inhibitors and some appreciable side effects. To understand the structural and evolutionary relationship of these enzymes, we cloned and sequenced cDNAs coding for aldose and aldehyde reductases from human liver and placental cDNA libraries. Human placental aldose reductase (open reading frame of 316 amino acids) has a 65% identity (identical plus conservative substitutions) to human liver and placental aldehyde reductase (open reading frame of 325 amino acids). The two sequences have significant identity to 2,5-diketogluconic acid reductase from corynebacterium, frog ρ-crystallin, and bovine lung prostaglandin F synthase (reductase). Southern hybridization analysis of human genomic DNA indicates a multigene system for aldose reductase, suggesting the existence of additional proteins. Thus, the aldo-keto reductase superfamily of proteins may have a more significant and hitherto not fully appreciated role in general cellular metabolism.

Nine congenital defects were seen in six animals during necropsies of 27 aborted or stillborn and 25 neonatal squirrel monkeys (Saimiri sciureus) during a two-year period. The defects were left diaphragmatic hypoplasia with herniation; right renal aplasia in conjunction with a right cleft lip and primary palate; supernumerary left kidney; skeletal defects, hydrocephalus, and thyroid anomalies consistent with the campomelic syndrome; atresia ani; and ultimobranchial gland remnants. The high incidence of congenital anomalies (4.9% of births and 11.5% of nonsurviving births) is consistent with a previous report of congenital defects in squirrel monkeys.

The African green monkey has previously been found to be a promising model for the study of atherosclerosis. We have compared the plasma and HDL cholesterol response to dietary manipulation in the two subspecies of African green monkeys (vervets and grivets) most often imported for biomedical research purposes. Twenty vervets and 20 grivets were fed, in succession, diets containing safflower oil, butter, or lard as the principal dietary fat at a level of 40% of calories. Ten animals of each subspecies were fed the diets without added cholesterol (control groups) and 10 were fed diets with either added crystalline cholesterol (safflower oil and butter diets) or egg yolk (lard diet) to raise the diet cholesterol level at least five-fold. The effect of the type of dietary fat was that total plasma cholesterol (TPC) and HDL cholesterol concentrations were lowest while the safflower oil diet was fed, were significantly higher when butter fat diets were fed, and were highest when the egg yolk-lard based diets were fed. In addition, a significant effect of the elevated level of dietary cholesterol, independent of the type of dietary fat, was seen: a statistically significant negative correlation between TPC and HDL cholesterol concentrations was induced. In contrast, a positive correlation between TPC and HDL cholesterol concentrations was found at the lower dietary cholesterol level. Thus, the different factors (type of fat versus cholesterol) influenced lipoprotein metabolism in distinct yet related ways. Although average values for both plasma and HDL cholesterol concentrations were significantly higher in the grivet subspecies than in the vervet subspecies, the data for both subspecies fit the same regression lines. This outcome suggested that the subspecies differed in the magnitude of response rather than in the mechanism of response.

Recombinant DNA clones encoding the neurotensin/neuromedin N precursor protein have been isolated from both bovine hypothalamus cDNA and rat genomic libraries using a heterologous canine cDNA probe. Nucleotide sequence analysis of these clones and comparison with the previously determined canine sequence has revealed that 76% of the amino acid residues are conserved in all three species. The protein precursor sequences predicted from bovine hypothalamus and canine intestine cDNA clones vary at only 9 of 170 amino acid residues suggesting that within a species identical precursors are synthesized in both the central nervous system and intestine. The rat gene spans approximately 10.2 kilobases (kb) and is divided into four exons by three introns. The neurotensin and neuromedin N coding domains are tandemly positioned on exon 4. RNA blot analysis has revealed that the rat gene is transcribed to yield two distinct mRNAs, 1.0 and 1.5 kb in size, in all gastrointestinal and all neural tissues examined except the cerebellum. There is a striking variation in the relative levels of these two mRNAs between brain and intestine. The smaller 1.0-kb mRNA greatly predominates in intestine while both mRNA species are nearly equally abundant in hypothalamus, brain stem, and cortex. Sequence comparisons and RNA blot analysis indicate that these two mRNAs result from the differential utilization of two consensus poly(A) addition signals and differ in the extent of their 3' untranslated regions. The relative combined levels of the mRNAs in various brain and intestine regions correspond roughly with the relative levels of immunologically detectable neurotensin except in the cerebral cortex where mRNA levels are 6 times higher than anticipated.

The size of low density lipoproteins (LDL) is strongly correlated with LDL cholesteryl ester (CE) content and coronary artery atherosclerosis in monkeys fed cholesterol and saturated fat. African green monkeys fed 11% (weight) fish oil diets have smaller LDL and less CE per LDL particle than lard-fed animals. We hypothesized that this might be due to a lower plasma lecithin:cholesterol acyltransferase (LCAT) activity in fish oil-fed animals. Using recombinant particles made of egg yolk lecithin-[14C]cholesterol-apoA-I as exogenous substrate, we found no difference in plasma LCAT activity (27 versus28 nmol CE formed per h/ml) of fish oil- versuslard-fed animals, respectively; furthermore, no diet-induced difference in immunodetectable LCAT was found. However, plasma phospholipids from fish oil-fed animals were over 4-fold enriched in n-3 fatty acids in the sn-2 position compared to those of lard-fed animals. Additionally, the proportion of n-3 fatty acid-containing CE products formed by LCAT, relative to the available n-3 fatty acid in the sn-2 position of phospholipids, was less than one-tenth of that for linoleic acid. The overall rate of LCAT-catalyzed CE formation with phospholipid substrates from fish oil-fed animals was lower (5–50%) than with phospholipid substrates from lard-fed animals. These data show that n-3 fatty acids in phospholipids are not readily utilized by LCAT for formation of CE; rather, LCAT preferentially utilizes linoleic acid for CE formation. The amount of linoleic acid in the sn-2 position of plasma phospholipids is reduced and replaced with n-3 fatty acids in fish oil-fed animals. As a result, LCAT-catalyzed plasma CE formation in vivois likely reduced in fish oil-fed animals contributing to the decreased cholesteryl ester content and smaller size of LDL particles in the animals of this diet group.

Adult male african green monkeys (vervets) had diurnal fluctuations in serum androgen and estradiol-17βconcentrations. Peak values for total androgen were obtained between 2100 and 0600 h while peak values for estradiol were found between 2400 and 0600 h.

A rapid scanning spectrometer for oscillographic presentation has been built for use in the “photo-conductive” infra-red region. It is designed to present spectra from 0.36μ to better than 5μ using a PbTe cell. The CO_2 doublet at 4.2μ is resolved with a scanning rate of 120 cycles per second and a scanned interval of better than 1.5μ with fluorite optics. A wave-length calibrating device has been incorporated into the instrument; this presents a fiduciary scale, synchronized with the spectrum, on the second beam of the twin-beam cathode-ray oscillograph. Adequate solutions have been found for the problems of synchronizing oscilloscope sweep and scanning drive, and for the problems of amplifier design for the sensitive cells.

The emission spectrum of the hydrogen-fluorine flame has been studied with prism resolution in the fundamental, as well as in the first and second overtone regions. Flame temperatures of approximately 4000°K are estimated from the spectroscopic data, and although due to insufficient resolution and difficulties of self-absorption, it is not possible to determine whether there is equipartition of energy between vibrational and rotational modes of excitation. However, the present experiments, together with previous high resolution absorption studies, do permit new and improved values of the molecular constants to be determined, namely, B_0=20.569 cm^−1, α=0.751cm^−1, D_0=2.42×10^−3 cm^−1, v_1=3961.31cm^−1, and v_2=7751.84 cm^−1.

A Perkin-Elmer Model 83 Monochromator covering a spectral range from the ultraviolet to 5.5μ is used for determining the light intensity as a function of time of an explosion in a bomb. [ Bullock Hornbeck Silverman , J. Chem. Phys.18, 1114 ( 1950)]. The radiation entering the spectrometer is chopped to allow ac amplification of the detector output with provision to allow transmission as well as emission measurements. A frequency modulated pressure gauge is used to determine the pressure change in the bomb. Time resolution of the order of magnitude of 10^−3 sec may be obtained for both spectral and pressure observations. Results for typical carbon monoxide-oxygen explosions are shown. These preliminary results seem to indicate that there is equilibrium for approximately 0.02 sec after the flame front reaches the vessel wall.