Remodeling the Specificity of an Endosomal CORVET Tether Underlies Formation of Regulated Secretory Vesicles in the Ciliate Tetrahymena thermophila

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Rotating drum fermentor for plant cell suspension cultures

A rotating drum fermentor designed for plant cell suspension cultures was constructed and tested. The oxygen transfer coefficient (k(L)a) and power requirements in the fermentor were determined with the water system under various conditions and the relationship between them in the fermentor was clarified. Also, the relationship between k(L)a and the apparent viscosity in the fermentor was investigated in the cell suspension system. The rotating drum fermentor was found to be superior to the mechanically agitated fermentor in the capacity of oxygen supply under high viscosity and low hydrodynamic stress conditions. This finding was also confirmed by the experiments with plant cell suspension cultures.     

A fossil baboon skull from the lower Omo basin,southwest Ethiopia

A well-preserved fossil skull assignable to the genusPapio was discovered in the late Pliocene deposits at the “White Sands locality” of the lower Omo basin, southwest Ethiopia in November 1978. This skull obviously belongs to a male baboon which is morphologically somewhat different from the extant species ofPapio and closely resemblesPapio baringensis R. E. F. Leakey, 1969. Its muzzle is not only long but comparatively wide and robust with a very flat dorsum, an almost quadrate vertical cross section, short and obtuse maxillary ridges and virtually absent maxillary fossae, and its zygomatic portion flares laterally to widen the large temporal process of the zygomatic bone. The post-orbital constriction is very marked, the temporal fossa is squarish in basal view, and the sagittal crest is placed rather posteriorly and meets a large nuchal crest, all of which suggest heavy temporal musculature. The incisors are lacking but were probably not as small as inP. baringensis. As a result of morphological comparisons with extant and fossil species ofPapio, this newly discovered skull was considered to represent a new species,Papio quadratirostris.     

A bioeconomic study on a provisioned troop of Japanese monkeys (Macaca fuscata fuscata) at koshima islet,Miyazaki

The natural and provisioned (wheat) food intake of the Japanese monkeys on Koshima was measured by direct observation. It was found that the portion of wheat consumed reflects such social structures in Japanese monkeys as (a) the structure of cocentric circles composed of several classes, (b) female ranking orders, (c) social strictness in breeding or non-breeding seasons. The natural food intake forIcho (2–3 years old female) was estimated for three seasons (April, September and December) during 1971. Her daily caloric intake was estimated from a quantitative list of natural foods eaten and the quantity of wheat eaten by multiplying the appropriate caloric values, and digestibility of 70%. The kcal day per values were 411 in spring, 522 in summer and 559 in winter. Her daily energy consumption (DEC) was estimated to be 398, 423, and 447 kcal/day in the respective seasons derived from the equation DEC =153W^2/3 which was obtained from data on activity telemetry and basal metabolic rates. The two spring values are in agreement. The summer and winter values show considerable differences. The dependency on wheat was calculated for individuals of various ages and sexes. The dependency of juveniles (60%) is about double that of ordinary females (25%). The Koshima troop is largely dependent on the evergreen broad leaves through all seasons. The increase of the number of females was cumulatively simulated assuming constant age-specific fecundity and mortality. There appeared one stagnated period of increase during the years 1961–1964 due to external factors. It will be a future problem to relate the quality of nutrition to reproductive performance.     

A theory of learnability

A new theory of learning is presented. Learning has been discussed by philosophers as a problem of acquiring knowledge. Historically, we can distinguish empiricism and rationalism. The rationalist insists that the essential part of our knowledge is innately built in ourselves, while the empiricist asserts that all knowledge derives from experience. The statistical learning theory originating in Perceptron is conceptually based on the association psychology which is one of the schools of empiricism. A recent study of language learning, however, informs us that, only from the rationalist standpoint of view, we can interprete the evident fact that one knows a remarkable amount of matters which he has never learned before. From this standpoint, the present paper deals with the mystery: done can know all from hearing one, i.e., a word to the wise is enough, and mathematically demonstrates that such a possibility of knowledge acquisition manifests highly topological characteristics. This will give some new suggestions to the study of pattern recognition and learning.     

The effects of 20 days bed rest on serum lipids and lipoprotein concentrations in healthy young subjects

The effects of 20 days bed rest (BR) on serum lipids and lipoprotein concentrations were investigated in 23 healthy young subjects (13 males and 10 females, aged 19 to 25 yr.). After 20 days BR, VO2max was reduced in both genders, but body composition did not change. The ratio of glucose area to insulin area during an oral glucose tolerance test decreased gradually throughout BR, which suggested a decrease in insulin sensitivity. Estimated changes in plasma volume from the beginning of BR were largest at day 3 of BR (-9.1% in females and -3.4% in males) and seemed to return the initial level at the end of BR in both genders. The increase in serum triglycerides and the decrease in high density lipoprotein (HDL) cholesterol, and apolipoprotein AI were observed in both genders during BR. In a smaller study of 4 males and 5 females, 20 days BR was associated with a decrease in HDL, cholesterol, a decrease in apolipoprotein AI and apolipoprotein AII, decrease in a plasma postheparin lipoprotein lipase activity and an increase in very low density lipoprotein triglyceride. Overall, the data suggested that the decrease in lipoprotein lipase activity and insulin sensitivity may contribute to the impairment in HDL metabolism.     

Mixed-ligand rhenium(V) oxo monomers with triphenylphosphine oxide and lopsided and symmetrical heterocyclic ligands. Putative intermediates in rhenium(V) oxo synthetic chemistry

Normally, ReOCl₃ (Me₂S) (OPPh₃) (1) serves as a useful source of ReO³⁺ or ReOCl_x^(3−x)+ for the synthesis of Re complexes by ligand exchange. Complexes of the type ReOCl₃(OPPh₃)(L) (L = 1,5,6-trimethylbenzimidazole (Me₃Bzm) (2); 3,5-lutidine (3,5-lut) (3); pyridine (py) (4)) were prepared from 1 and one equivalent of L. Formation of these mixed-ligand complexes is unsual because the normally labile OPPh₃ in 1 was retained. Addition of non-coordinating triethylamine (NEt₃) gave [HNEt₃][ReOCl₄(OPPh₃] (5). The anion in 5 has been populated to be an intermediate in some synthetic schemes. ReOCl₃(OPPh₃)(Me₃Bzm) (2) was characterized by X-ray crystallography. Crystallographic data are: C₂₈H₂₇Cl₃N₂O₂PRe, P2₁/c, A = 18.503(3), B = 9.780(2), C = 15.735(4) Å, β = 97.56(2)°, D_calc = 1.76 g cm⁻³, Z = 4, R = 0.041, R_w = 0.066 for 3193 independent reflections. In 2, the pseudo-octahedral Re has the OPPh₃ ligand trans to the oxo ligand, and one of the OPPh₃ phenyl rings lies nearly over the five-membered ring of Me₃Bzm. Reaction of ReOCl₃(OPPh₃)(Me₃Bzm) (2) with one equivalent of 3,5-lut or py resulted in the precipitation of mixed-ligand species best formulated as Re₂O₃Cl₄(Me₃Bzm)₂(3,5-lut)₂ (6) and Re₂O₃Cl₄(Me₃Bzm)₂(py)₂ (7), respectively.     

Functional expression of human and mouse low density lipoprotein receptors in hybridomas

Though a mouse.human-human heterohybridoma, N12-16.63, secreting an antitetanus toxoid human monoclonal antibody grew well in a serum-free medium, its high producing subclone N12-69 required SSGF-I, a low density lipoprotein (LDL) from swine serum, or human-LDL (h-LDL) for growth. The growth-promoting action of SSGF-I was caused by its lipid fraction, and SSGF-I could be replaced completely with cholesterol in the presence of bovine serum albumin (BSA). Thus, cell line N12-69 is a cholesterol auxotroph of the heterohybridoma. N12-69 cells express both mouse and human LDL receptors on the cell surface in a ratio of 1:4. SSGF-I bound to both receptors with the same binding affinity, and h-LDL was also take up by the same receptors, though the affinity constant of the receptors for SSGF-I was 1.5 times stronger than that for h-LDL. The growth of N12-69 cells was completely inhibited by the addition of dextran sulfate, which is known to inhibit the binding of LDL to LDL receptors, to an SSGF-I or h-LDL containing medium but was not inhibited at all when dextran sulfate was added to a serum-free medium supplemented with cholesterol and BSA. Furthermore, an anti-human LDL receptor monoclonal antibody partially inhibited the growth of N12-69 cells in an SSGF-I or h-LDL containing medium. These findings suggest that N12-69 cells express both biologically active mouse and human LDL receptors on their cell surfaces and that SSGF-I or h-LDL is taken up by the both receptors to be utilized as a cholesterol source for the growth.