Three new species of penicillium

Three new species of microfungi belonging to the genus Penicillium Link ex Fries are described and illustrated. All but one have been isolated from the atmosphere of las Palmas, capital city of the island of Gran Canaria (Canary Islands, Spain). They clearly differ from all species of the genus described so far and are, therefore, described and proposed as new species: Penicillium hispanicum sp. nov., Penicillium grancanariae sp. nov., and Penicillium palmensis sp. nov.     

Dose-Dependent Cytokinetic Changes Following 1-β-D-Arabinofuranosylcytosine and Hydroxyurea In L1210 and S-180 In Vivo

DNA synthesis inhibition and recovery in L1210 and S-180 ascites tumors following 1-β-D-arabinofuranosylcytosine (Ara-C) and hydroxyurea (HU) were measured autoradiographically as a basis for optimizing drug schedules. Tumor bearing mice, 10⁶ cells day O, were treated on day 4 with 20, 200 or 2000 mg/kg Ara-C or 50, 300 or 1800 mg/kg HU. At various intervals following drug, [³H]thymidine was administered i.p. and mice were killed 1 hr later. Tumor cells were analyzed for labeling index (LI) and grain count (GC) to determine the percentage of cells in S phase and the distribution of DNA synthesis rates among the labeled cells, respectively. Following each dose of HU, DNA synthesis was inhibited completely. Recovery of LI was rapid and approached control values by 6 hr. Following each dose of Ara-C, DNA synthesis was inhibited completely for at least 6 hr. Recovery of LI was first noted 6 hr following 20 mg/kg Ara-C and 9 hr following 200 mg/kg. Following both doses the LI reached 100% of the control value by 26 hr. GC analysis indicated that following Ara-C treatment, DNA synthesis was reinitiated first with cells with low GC from 6 to 12 hr followed by cells with increasing GC from 12 to 20 hr. the labeling intensity reached control values by 20 hr and an ‘overshoot’ occurred by 26 hr. These data suggest that the recovery of DNA synthesis rate is a gradual process. Survival data for mice receiving two doses of Ara-C indicated that the optimal interval for retreatment following the lower dose of Ara-C occurred by 6 hr as compared to 12–16 hr for the higher dose. These times coincided in both instances with recovery of LI to 33–50% of control values. Early recovery of LI may be the best method currently available for estimating the optimal time for retreatment with an S phase specific drug.     

Development,metamorphosis, and natural history of the nudibranch Doridella obscura Verrill (Corambidae: Opisthobranchia)

The doridacean nudibranch Doridella obscura Verrill was raised through one complete generation in laboratory culture, and spawning behavior monitored for a year at monthly intervals in Barnegat Bay, New Jersey.The nudibranch deposited egg masses throughout the year in Barnegat Bay, and the larvae remained viable at temperatures ranging from 1.5 to 28 °C. At 25 °C the eggs hatch 4 days after oviposition, and the planktotrophic veliger larvae swim and feed for 9 days before they metamorphose. Settlement occurs specifically on the bryozoan Electro crustulenta (Pallas). The spirally coiled larval shell grows rapidly until the dorsal mantle fold is retracted from the aperture 5–6 days after hatching. Although starved larvae grow only slightly and do not metamorphose, they resume normal development on introduction of suitable food. Newly metamorphosed juveniles consume algae and debris on the surface of the bryozoan until they grow large enough to attack the living zooids of E. crustulenta.The life cycle of Doridella obscura is short (26 days at 25 °C), allowing the nudibranchs to take advantage of short-lived Electra crustulenta colonies in unstable habitats in bays and estuaries.     

Physiological Adaptation to the Loss of Amino Acid Transport Ability

A strain of Neurospora crassa devoid of constitutive amino acid transport ability can utilize arginine as the sole nitrogen source. Nitrogen starvation, presence of arginine, and mutational inactivation of the general permease are key factors in signaling production of an extracellular enzyme which removes the alpha-amino group from the amino acid.     

Lysosomal proliferation in rachitic avian intestinal absorptive cells following 1,25-Dihydroxycholecalciferol

Lysosomes in chick intestinal absorptive cells from rachitic (vitamin D-deficient) and vitamin D-replete animals were studied utilizing transmission electron microscopic histochemistry and ultrastructural morphometry. Absorptive cells from rachitic animals, serum calcium = 7.3±0.3 mg%, contained an average of 4.0±0.3 supranuclear lysosomes. In rachitic chicks sacrificed 9 hr post-injection of 1,25-dihydroxycholecalciferol, the active metabolite of vitamin D, the values for both serum calcium, 9.8 ± 0.2 mg%, and the number of apical absorptive cell lysosomes, 12.9±0.6, were increased over non-injected or vehicle-only injected animals. Lysosomes in vitamin D-replete absorptive cells were characterized by their intense staining with pyroantimonate, indicative of their high calcium content. The same organelles also produced a positive reaction for acid phosphatase. Rachitic lysosomes, also acid phosphatase positive, were only lightly stained with pyroantimonate. The lysosomal proliferation apparently induced by 1,25-dihydroxycholecalciferol may be a further indication that these organelles play a role in intestinal calcium transport and/or intracellular calcium homeostasis within the absorptive cell.     

Biogenesis of mitochondria. 52

Summary The characteristics of recombination of several petite (rho ^-) mutants of S. cerevisiae that retain the -influenced region of the mitochondrial genome, identified by the markers cap1-r, ery1-r and tsr1, are described. The petites were derived from an ^– grande (rho ⁺) strain and those petites which retain all three markers show recombination properties similar to those of the ^- parental strain. However, other rho ^- mutants that retain the cap1 and ery1 loci but have lost the tsr1 locus, which is located between cap1 and ery1, show markedly different properties of mitochondrial transmission and recombination, consistent with the presence of ⁺ alleles. The association of an internal deletion between the cap1 and ery1 loci with a change in phenotype provides additional evidence for the location of between these two loci.Although the petites deleted for the tsr1 locus exhibited the recombination properties of ⁺ strains, it was not possible to transmit this characteristic to rho ⁺ recombinant cells. Experiments on the kinetics of elimination by ethidium bromide of the cap1 and eryl markers from the petites and measurements of the buoyant densities of their mtDNA species did not indicate major changes (such as selective sequence repetition) in the sequences of the mtDNAs. The possible nature of the changes in the mtDNAs of these petites is discussed in light of recent studies on the physical nature of the alleles.     

Sodium binding in Halobacterium halobium measured by the nuclear magnetic resonance technique

Relaxation time measurements T₁ and T₂ of sodium in Halobacterium halobium pellets were carried out at two frequencies. From those measurements, combined with intensity measurements of the sodium in the system, estimation of the properties of the sodium ions in the system was carried out. It is suggested that three types of sodium ions are present in the bacterial pellet. (A) The extracellular sodium with properties of free solution and (B) sodium which is in the pericellular volume between the cell wall and the cell membrane. There is an exchange between type A and type B sodium. The type B sodium has (e²qQ)/h = 3.7 · 10⁷ rad/s, τ_cB = 5.2 · 10⁻⁶ s and τ_B = 1 · 10⁻³ s. The sodium of type C is bound inside the cell and undetected. It's concentration inside the cell is assumed to be 1.9 M.     

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.