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The activity of urea cycle enzymes was assayed in duodenal biopsy specimens obtained from a female infant who presented with neonatal hyperammonaemia. All enzyme levels were normal except N-acetyl glutamate-dependent carbamyl phosphate synthetase 1 (CPS1) which was half the mean activity in normal control specimens. A similar deficiency of CPS1 was also shown in duodenal specimens from the patient's mother who became slightly symptomatic after relatively high protein meals and during pregnancy, and had spontaneously modified her diet to one with protein restriction. The patient is growing normally on a dietary regimen similar to that spontaneously adopted by her mother. Urea cycle enzyme activity in the duodenal biopsy material from the controls was similar to that found in the normal human liver and appears to have distinct advantages as a means of assaying for urea cycle defects in patients with hyperammonaemia and their relatives. Show less

The language of spatial metaphor is both old and familiar: "You seem far away tonight," or "He stands head and shoulders above the crowd." It is vivid and evocative language. When put in the service of therapy, it is capable of clarifying and intensifying aspects of interpersonal relationships which ordinarily remain obscure. This paper explores the deliberate use of space as a metaphor representing interpersonal and emotional realities. Family sculpture, as pioneered by Kantor, Duhl, and Duhl (1973), and elaborated by Simon (1972), Papp (1976) and others, develops a spatial metaphor involving the entire family. This metaphor is both descriptive, clarifying emotional reality, and therapeutic, suggesting avenues for change and growth. We will illustrate the use of this vocabulary as it applies to two-person systems: therapist-patient interactions and the marriage relationship. Show less

Primary chick myoblast cultures demonstrate the ability to take up exogenously supplied polyadenylated RNA and express the encoded information in a specific manner. This expression is shown to exhibit tissue specificity. Analysis of creatine kinase activity monitored at various times of incubation in the presence of either polyadenylated or nonpolyadenylated RNA indicates that only the poly(A)+ mRNA is capable of being actively translated. Radioactively labled poly(A)+ mRNA is taken up by the cell cultures in a time-dependent manner and subsequently shown to be associated with polysomes. This association with polysomes does not occur in the presence of puromycin and is unaffected by actinomycin D. Thus, nonspecific interaction with polysomes and induction of new RNA synthesis are ruled out and the association of the exogenously supplied poly(A)+ mRNA with polysomes is indicative of its translation in the recipient cells. When heterologous mRNA (globin) is supplied to the myoblasts, it is also taken up and properly translated. In addition, exogenously supplied myosin heavy chain mRNA is found associated with polysomes consisting of 4-10 ribosomes in myoblast cell cultures while in myotubes it is associated with very large polysomes, thus reflecting the different translational efficiencies that this message exhibits at two very different stages of myogenesis. The results indicate that muscle cell cultures can serve as an in vitro system to study translational controls and their roles in development. Show less

Radioactively labeled myosin heavy chain messenger ribonucleic acid (MHC mRNA) synthesized during the pre-fusion stage of chick embryo breast muscle cell culture is transferred from messenger ribonucleic acid proteins (mRNPs) to the polysomal MHC mRNA during the period of rapid increase in the rate of MHC synthesis (mid-to late-fusion). This transfer constitutes a major contribution to the rate of incorporation of 3H-labeled transcripts into polysomal MHC mRNA at this time. As the increase in the rate of MHC synthesis levels off (late-to post-fusion) the contribution to the rate of incorporation of 3H-labeled transcripts into polysomal MHC mRNA from newly synthesized transcripts increases until it becomes predominant. In vivo, the level of MHC mRNP increases during early stages of embryonic development and then decreases when MHC synthesis and the level of polysomal MHC mRNA has been shown to increase. Show less

Mutations leading to decrease or absence of orthophosphate-repressible acid phosphatase activity have been studied. It is shown that these mutations can arise in three genes: acp1, acp2 and acp3, which are not linked. Genes acp1 and acp2 have been studied previously; the existence of the gene acp3 is demonstrated in this paper. It is established that all mutations in the acp3 gene are recessive, are leaky and epistatic to the constitutive mutations in all known regulatory genes for acid phosphatase II synthesis - acp4, acp80, acp81, acp82, acp83, and acp84. The gene acp3 is not linked with these regulatory genes, but it is closely linked with the structural gene for constitutive acid phosphatase - pho1 (D=0.33+/-0.20 cM). The pho1 gene has been recently located on the right arm of chromosome II on the left of the gene lys2. Mutations lacking activity of constitutive and repressible acid phosphatases simultaneously have been found. It is shown that these mutations are allelic to mutations in the gene acp3 and pho1 simultaneously. Two hypotheses are proposed about the role of the gene acp3: the gene controls the positive factor for the repressible acid phosphatase synthesis or the structure of the enzyme. Show less

Asparaginase II (L-asparagine amidohydrolase, EC 3.5.1.1) activity of cells from stationary phase cultures of Saccharomyces cerevisiae is very low. When these cells are inoculated into minimal medium, asparaginase II specific activity rises rapidly and reaches a maximum after 9-10 h. During the next 2.5-3 h, a rapid decrease in asparaginase II specific activity occurs. The enzyme does not appear to be secreted into the medium or to be reabsorbed into the cell. Addition of protease inhibitors at the time of maximum activity partially or totally prevents the loss of asparaginase II. L-1-Tosylamide-2-phenylethyl chloromethyl ketone decreases the rate of loss. The sulfhydryl reagents p-hydroxymercuribenzoate and iodoacetamide inhibit the loss of asparaginase II. However, addition of EDTA causes a further increase in activity. This increase is due to de novo protein synthesis. The effect of EDTA can be reversed by the addition of Zn2+. The most likely explanation for the rapid loss of asparaginase II is proteolytic degradation by a Zn2+-dependent, thiol protease or peptidase. Show less

An unusual metastasis of adenocarcinoma of the lung to the gingival mucosa in a 75-year-old man is reported. The case presents an interesting differential clinical assessment as the gingival lesions seem to be of local nature and involve a combined endodontic-periodontic causation. Show less

Administration of FSH antiserum to adult rats for 14 or 30 days had no or little effect on body, testis or accessory sex gland weights, androgen-binding protein, testosterone levels, germ cell numbers or fertility, thus indicating a relative insensitivity of the testis to withdrawal of FSH. Unlike immature rats, therefore, which do require FSH to initiate spermatogenesis, adult rats do not need this hormone to maintain spermatogenesis. Show less

In the light of earlier work [1] which demonstrated the presence of a large number of myosin heavy chain (MHC) transcripts in chick myoblasts prior to cell fusion and the burst of MHC synthesis it was of great interest to determine the subcellular localization of the still inactive transcripts. It has been determined in differentiating muscle cells in culture. Two populations of cells were examined -- monucleated myoblasts just prior to cell fusion and myotubes where at least 80% of the cells were fused. Utilizing a myosin complementary DNA (cDNA) probe [2] it is observed that just prior to cell fusion, when the "burst" of myosin synthesis has not yet occurred, the vast majority of cytoplasmic myosin mRNA transcripts are found in a stored messenger RNA protein complex with a minimal amount found in the heavy polysome fraction. In differentiated myotube cultures, when myosin synthesis is progressing at a high rate, the reverse is found, i.e, the amount of stored myosin messenger RNA (mRNA) is minimal while the largest amount of myosin mRNA transcripts are localized in the polysome fraction. The number of total cytoplasmic myosin transcripts is found to decrease after cell fusion at a time when myosin synthesis is maximal suggesting that the efficiency of translation of myosin mRNA increases during terminal differentiation. Show less

Protein carboxyl-methylase (PCM), the enzyme that transfers methyl groups from S-adenosyl-methionine to free carboxyl groups on proteins, is highly localized in testes. The cellular distribution of PCM and its substrates, the methyl acceptor proteins, was investigated. Separation of testicular cells on an albumin gravity gradient revealed the preferential localization of both enzyme and substrates in spermatids. In young rats, PCM activity increases with age coincidently with germ cell maturation. Rats which are heterozygous for the Hre gene (Hre/+) are infertile as a result of germ cell depletion. In these animals, testicular PCM specific activity and total activity were, respectively, 4--6 and 40--50 times lower than in normal testes. Enzyme activity in testes from animals with x-ray-induced germ cell depletion was also very low. These observations suggest that PCM is located in germ cells. Show less

Double lip, an accessory fold of redundant mucous membrane inside the vermilion border, is differentiated from other chronic enlargements of the lip, and treatment for this congenital anomaly is outlined. Show less

A rat model to study the local effects of testicular vein ligation is described. One hour after unilateral testicular vein ligation, the testicular concentration of testosterone was significantly greater (P less than 0.01) on the side that was ligated than in the contralateral testis (177.1 +/- 19.7 [SEM] ng/gm of tissue as compared with 108.8 +/- 11.8 ng/gm of tissue, respectively). This effect was not seen 1 week after the testicular vein ligation. The testosterone concentration in the ligated testis was also higher than that in sham-operated animals. These differences in testicular testosterone concentration were not associated with changes in peripheral serum testosterone levels. ligation of the testicular vein causes an acute rise in the testicular concentration of testosterone and may thus mediate changes in testicular function. Show less

Different types of human germ cells show unusual features of the nuclear envelope. Spermatogonial nuclei demonstrate two kinds of modifications. The first one is a series of intranuclear flattened cisterns, parallel to each other and to the inner aspect of the nuclear envelope. The second one is a nuclear envelope protrusion into the cytoplasm occupied by a double membrane-limited vesicle. Pores are found on the membrane of the vesicle facing the interior of the nucleus. In spermatocytes the nuclear pores are concentrated over certain areas and completely absent from others. In the regions where they are absent a single cytoplasmic cistern of rough endoplasmic reticulum is closely apposed to the outer membrane of the nuclear envelope. Early modifications of the nuclear surface appear in spermatids before the attachment of the acrosomic vesicle and may indicate an active role of the nuclear envelope in the morphogenesis of the acrosome. In round spermatids nuclear pores are absent from the area which is first related to the Golgi and later covered by the acrosomal cap. Single or multiple layers of cytoplasmic annulate lamellae are closely associated with the nuclear envelope over the pore rich areas. Frequently there are intranuclear accumulations of dense material adjacent to the annulate lamellae-nuclear pore complex. The chromatoid body is usually present on the cytoplasmic side of this complex. In the elongating spermatids most annulate lamellae are free in the cytoplasm, often in relation with Golgi and chromatoid body remnants near the axial filament. Few stacks of annulate lamellae are noted adjacent to the pore rich nuclear regions. It is suggested that the described modifications are related to an active nuclear-cytoplasmic interaction. Show less

Monochromatic targets presented at 30 degrees excentricity on orange, magenta and blue backgrouds are used. A small monochromatic light, 476 nm on orange, 551 nm on magenta and 621 nm on blue, is flashed at 3 cps-1 on the centre of the targets. The size of the targets is varied and their luminance adjusted using neutral filters until the flashing light is just not visible. This method allows the study of chromatic mechanism sensitivity and of retinal interactions (summation and inhibition). Some observations in normal as well as in pathological conditions are presented. Show less

A clone panel containing various segments of human chromosome 11 has been selected and use for regional assignment of the gene for human lysosomal acid phosphatase (ACP2) to the short arm of chromosome 11, in the region 11p11 leads to 11p12. Further evidence has also been presented to update the regional assignment of the gene for lactate dehydrogenase A (LDHA) to 11p12 leads to 11p13, and to support a previous assignment of the genes for the two components of the human cell-surface antigens of the SA11 (previously designated AL) group, SA11-1 and SA11-3 (previously designated AL-a1 and AL-a3), to 11pter leads to 11p13. This regional clone panel will be useful for rapid regional mapping of other genes assigned to chromosome 11. Show less

Techniques of quantitative stereology have been utilized to determine the relative volume occupied by the Sertoli cells and germ cells in two particular stages (I and VII) of the cycle of the seminiferous epithelium. Sertoli cell volume ranged from 24% in stage I of the cycle to 32% in stage VII. Early germ cells occupied 3.4% in stage I (spermatogonia) and 8.7% in stage VII (spermatogonia and preleptotene spermatocytes). Pachytene spermatocytes occupied 15% (Stage I) and 24% (stage VII) of the total volume of the seminiferous epithelium. In stage I the two generations of spermatids comprised 58% of the total epithelium by volume, whereas in stage VII, after spermiation, the acrosome phase spermatids occupied 35% of the total seminiferous epithelial volume. Show less

A reliable and uniform vascular perfusion fixation method for the testis has been developed by using an initial washout solution containing a vasodilator and an anticoagulant. This is followed by a brief fixation with a sodium phosphate buffered formaldehyde-glutaraldehyde solution of conventional strenght, and then a second more concentrated aldehyde fixative solution containing picric acid. The method takes into account some of the unique features of the vascular supply of the male genital tract for its favorable perfusion and fixation. The advantages of this method are: (1) consistently favorable preservation of the testis; (2) simple and inexpensive apparatus; and (3) stable and relatively innocuous stock solutions. Show less

A procedure is described which permits the isolation from the prepuberal mouse testis of highly purified populations of primitive type A spermatogonia, type A spermatogonia, type B spermatogonia, preleptotene primary spermatocytes, leptotene and zygotene primary spermatocytes, pachytene primary spermatocytes and Sertoli cells. The successful isolation of these prepuberal cell types was accomplished by: (a) defining distinctive morphological characteristics of the cells, (b) determining the temporal appearance of spermatogenic cells during prepuberal development, (c) isolating purified seminiferous cords, after dissociation of the testis with collagenase, (d) separating the trypsin-dispersed seminiferous cells by sedimentation velocity at unit gravity, and (e) assessing the identity and purity of the isolated cell types by microscopy. The seminiferous epithelium from day 6 animals contains only primitive type A spermatogonia and Sertoli cells. Type A and type B spermatogonia are present by day 8. At day 10, meiotic prophase is initiated, with the germ cells reaching the early and late pachytene stages by 14 and 18, respectively. Secondary spermatocytes and haploid spermatids appear throughout this developmental period. The purity and optimum day for the recovery of specific cell types are as follows: day 6, Sertoli cells (purity>99 percent) and primitive type A spermatogonia (90 percent); day 8, type A spermatogonia (91 percent) and type B spermatogonia (76 percent); day 18, preleptotene spermatocytes (93 percent), leptotene/zygotene spermatocytes (52 percent), and pachytene spermatocytes (89 percent), leptotene/zygotene spermatocytes (52 percent), and pachytene spermatocytes (89 percent). Show less