The arrangement of nucleotides in the coding regions of natural templates

Summary The relation of the nucleotide sequences in the coding regions of natural templates and of the short nucleotide sequence in 3 terminus of 16 S ribosomal RNA was found to differ from random pattern. The observation is interpreted in terms of both the ribosomal interactions and the molecular evolution.     

An autecological study of Palicourea riparia Bentham as related to rain forest disturbance in Puerto Rico

Summary The present study is an attempt to understand biology of Palicourea riparia Bentham relative to the process of recovery following disturbance in a tropical rain forest in Puerto Rico. In this species seed germination and seedling maintenance are favored by environmental conditions associated with disturbance, yet germination and seedling persistence are significant in undisturbed forest conditions. The pattern of seed germination indicates that (1) the seeds possess a dormancy mechanism, (2) dormany is not evenly distributed within a seed population, and (3) some seeds can remain viable if buried in the soil for at least three years. Results from reciprocal transplant studies indicate that there has been no differentiation into growth ecotypes in this species. Photosynthetic rates are very low under both field and laboratory conditions. In the laboratory, photosynthetic rates are consistently enhanced by increases in light intensity. It is concluded that P. riparia is a species of wide ecological amplitude that acts as a gap opportunist.     

Sympathetic control on salivary secretion by the parotid gland in rabbit. I. Effects on the unstimulated gland (author's transl)]

The sympathetic influences on the rabbit unstimulated parotid gland were studied. The experiments were carried out in anaesthetized rabbits with the Stenon aduct cannulated. Direct stimulation of the superior cervical ganglion elicits variable salivary flows. The high amylase content in the saliva points to a sympathetic secretory action upon acinar cells. The administration of alpha-adrenergic blocking agents (dihydroergotamine, phentolamine and phenoxybenzamine) clearly reduces and even abolishes the effect of the sympathetic stimulation upon flow. The administration of a beta-adrenergic blocking agent (propranolol) slightly reduces the sympathetic action. However the amylase activity is greatly reduced. All this suggests that the secretory effects on the fluid fraction should predominantly be alpha-adrenergic while on the secretion of enzymes the beta-receptors should play an important role.     

Biochemical evidence for the non-inactivation of the steroid sulfatase locus in human placenta and fibroblasts

Summary Steroid sulfatase activities are significantly higher in placentas obtained after the birth of girls than after the birth of boys, and also in female fibroblasts compared to male strains. This constitutes biochemical evidence for the non-inactivation of the X-linked sulfatase locus. No hydrolytic activity is found in the fibroblasts of ichthyotic boys. Heterozygosity is demonstrated in the fibroblasts of the four mothers studied, as they have steroid sulfatase activity of less or equivalent to the normal male value.     

A family with a satellited Yq chromosome

Summary A large pedigree with a satellited Yq chromosome is described, Q, C, and NOR banding were performed. Family C proband suffers from a Klinefelter syndrome.     

Frequency and types of induced and spontaneous chromosome aberrations in relation to cell kinetics

Summary Induced and spontaneous structural chromosome aberrations (SCA) were studied in a child accidentally radiated with a high dose of ¹⁹²Ir, and in three sibs with Fanconi's anemia, analyzing by separate first division metaphases (FDM) and second division metaphases (SDM). The results showed that the number of SCA, number of cells with aberrations, and SCA per cell were markedly higher in FDM in all patients.Furthermore, for some type of structural changes like dicentric chromosomes and chromatid interchanges, the differences were particularly striking. The importance of ascertaining FDM identified with proper techniques, for the study of the clastogenic effect of environmental agents and some aspects related to the differences in cytogenetic features found in diverse tissues in Fanconi's anemia are discussed.     

Retinoblastoma,gross internal malformations,and deletion 13q14→q31

Summary A male patient with an interstitial deletion 13q14q31 is described. Our necropsy findings included a left retinoblastoma and several gross internal malformations. In this paper we reaffirm that band 13q14 is involved in cases of retinoblastoma and we propose, after studying accompanying cases of total or partial long arm trisomies 13, that the loss of specific 13q bands, from 13q14 to 13q31 is responsible for the congenital defects we are describing.     

The deafness,onycho-osteo-dystrophy,mental retardation syndrome

Summary Two new cases of the D.O.O.R. syndrome are reported. The patients described showed most of the characteristics described by Cantwell (1975) and some others that may represent additional clinical findings of this rare syndrome.     

Further studies on mevalonate phosphorylation in neonatal chick brain

Mevalonate phosphorylation was studied in neonatal chick brain. Formation of phosphorylated derivatives of mevalonic acid increased with the pH in the range assayed (5.5–9.5). Phosphomevalonate kinase was completely inactivated after treatment at 50°C for 5–10 min, whereas mevalonate kinase was found to retain its activity under the same conditions. Exposure to 65°C for 5 min resulted in the inactivation of mevalonate kinase. Both mevalonate-activating enzymes from chick brain were located primarily in the soluble fraction. The amounts of phosphomevalonic acid and pyrophosphomevalonic acid did not show a significant diurnal variation to suggest the presence of a circadian rhythm in either kinase. Cholesterol feeding and fasting had no effect on mevalonate phosphorylation by neonatal chick brain.     

Activity of some enzymes of energy metabolism during denervation and reflex atrophy in rat slow and fast muscles

The loss of muscle weight in the soleus (SOL) and extensor digitorum longus (EDL) muscles was compared after denervation and in the course of reflex muscle atrophy induced by unilateral fracture of metatarsal bones of the paw and local injection of 0.02 ml turpentine oil subcutaneously. This so-called reflex atrophy is significantly greater after 3 days than that after denervation. Seven days after the nociceptive stimulus, reflex and denervation atrophy are grossly similar in both muscles. This also applies in case that the nociceptive stimulus had been repeated on the third day. The EDL:SOL enzyme activities of energy supply metabolism reflect the differences between a glycolytic-aerobic (EDL) and predominantly aerobic type (SOL) of muscle. No consistent changes were found in either type of atrophy after 3 days. In 7 days' denervation, the activity of hydroxyacetyl-CoA-dehydrogenase (HOADH) and citrate synthase (CS) was decreased in the SOL, while glycerolphosphate:NAD dehydrogenase (GPDH) was enhanced. In the EDL, the activity of triosephosphate dehydrogenase (TPDH), GPDH, malate dehydrogenase (MDH), CS and HOADH was decreased. Acid phosphatase (AcP) was greatly increased in both muscles. Seven days after application of the nociceptive stimulus, all enzyme activities were altered in a grossly analogous manner as after denervation.