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A simple conversion of the previously described (1) tricyclic ester 1into the pentacyclic songorine intermediate 21is described. The process is stereospecific and it operates in an overall yield of 7.8%.

Cerebral angiograms were performed on 14 dogs following various periods of cardiac arrest (3-15 min) produced by fibrillating (A.C fibrillator) the heart after opening the chest. The heart beat was restored to normal by means of cardiac defibrillation, massage, or injection of epinephrine and sodium bicarbonate directly into the heart. Each dog was followed 3 to 5 hr after resuscitation. When circulatory arrest lasted longer than 5 min, cerebral angiographic changes of no-reflow phenomenon began to occur between 3 and 4 hours after resuscitation. These findings were 1) marked prolongation of the arterial phase in both intracranial and extracranial arteries, followed by 2) dilatation of the proximal intracranial arteries with nonfilling of the distal intracranial arteries in some cases, and 3) faint visualization of the venous phase. During the period of abnormal angiographic findings the carotid pressure, jugular venous pressure, blood viscosity, arterial pH, and PCO2were normal. PO2was normal in most cases. The CSF pressure was normal or only slightly elevated. The carotid flow rate, however, was reduced by nearly 60 of the control level. No significant abnormalities were noted in 3 dogs in which less than 5 min of arrest was induced. Each dog was sacrificed when the angiographic findings were present. The histologic findings were congestion, endothclial proliferation, stasis of red blood cells in the vessels, and even early ischemic necrosis of the brain tissues.

A temperature-sensitive mutation in gene 32 was used to study the role of gene 32 protein in the repair of UV-damaged DNA of bacteriophage T4. It was possible to distinguish between repair and replication of DNA at 33 C. At this temperature, DNA replication continued, and the intracellular DNA was stable. In contrast, no significant repair of UV-damaged DNA was observed even 40 min after the irradiation. Therefore, it was concluded that the defect in the repair mechanism at this temperature is not a simple consequence of the defect in DNA replication but that gene 32 apparently has an independent role for DNA repair. It was reported previously that gene 32 product is required for both T4 DNA replication and genetic recombination. In addition to these findings, this study has given direct evidence that, in vivo, this protein is also essential for the UV repair mechanism.

Martin Joos once said: “In matters of language, Chao never goes wrong,” or words to that effect. I certainly appreciate this great compliment, but in many ways which Martin has not noticed, I did go wrong quite a number of times in matters of language.It goes without saying that in my pre-adult speech, which was of course way back in the pre-Martin Joos days, there were a number of things in which I deviated from the speech of my environment. In the form of Mandarin spoken around me retroflex initials were distinct from dental sibilants; I used dental sibilants for both. There was also final nafter front vowels, but I dropped all the final n’s. Thus, when I noticed that a cat had lapped up my bowl of noodles, I exclaimed: Mhautsy woode mieh!for Mhauchy woode miann!‘The cat is eating my noodles!’

Chronic feeding of rats with 1% boric acid impairs growth more in those on zero riboflavin than in those receiving 133 mcg. riboflavin/100g. diet. Guinea pigs on a diet containing 28 mcg. riboflavin/100g. diet show skin changes and a significant mortality when fed 1% boric acid. Toxicity is minimal in riboflavin-repleted animals (1.6 mg./100g. diet) fed the same level of boric acid. Chicks receiving riboflavin in excess of the accepted growth requirement show a decreased incidence of boric acid toxicity. Intraperitoneal injection of 2-14C-riboflavin results in a significantly greater urinary excretion of labeled riboflavin in boric acid-fed animals than in controls for both rats and guinea pigs. Studies in vitroshow that the binding of riboflavin to serum proteins is reduced by borate, even in very low concentrations. It is concluded that riboflavin depletion can be induced by borate.

Independently derived man-mouse somatic cell hybrids and their derivative subclones show a positive correlation between the expression of human lactate dehydrogenase A subunits and the occurrence of the human C-11 chromosome. Data are also presented that confirm the previously reported linkage of the thymidine kinase locus to the E-17 chromosome. A translocation of the E-17 chromosome provides presumptive evidence for the assignment of the thymidine kinase locus to the long arm segment of the E-17 chromosome. This translocation also provides evidence for translocation between man and mouse chromosomes in somatic cell hybrids. A presumptive association between the human phenotype for isocitrate dehydrogenase and the human F group is also described. Identification of specific human chromosomes was achieved by the application of several new cytological techniques: measurement of chromosome arm length, in situannealing with mouse satellite complementary RNA, constitutive heterochromatin staining with Giemsa, and quinacrine mustard fluorochromatic staining.

Five cases of significant asymmetry of the internal auditory canals as a normal variant are reported; these were proven normal by iophendylate injection tomographic study. The incidence of significant asymmetry of the canals between the two sides is 2% in our series. Even when significant asymmetry in size and configuration of the internal auditory canals is present, a conclusive diagnosis cannot by made without the benefit of iophendylate injection cisternography. The technique of cisternography using a small amount of iophendylate injection (1 to 3 ml) combined with polytomography is described briefly.

The gaschromatographic behavior of perhaloalkanes containing one or two carbon atoms and different kinds of halogen atoms in a molecule was investigated. The logarithm of the specific retention volume was correlated well with the halogen composition, the boiling point, the estimated volume of molecule and the molar refractivity of these compounds.

Based on an empirically extended Landau roton formula and on the fact that3He atoms participate in the movement of the normal component of liquid4He, the variation of the ? temperature with3He concentration is obtained at the saturated vapor pressure. The results are in good agreement with experiment. The present approach can also be applied to higher pressures.

The temperature dependence of Landau's ? parameter is obtained from the assumption thatp0 and µ are temperature independent. The density derivative of various parameters has also been estimated.

The ES-2 esterase is a kidney-associated esterase and is expressed in a cloned mouse renal adenocarcinoma cell line. Somatic cell hybridization of the mouse renal adenocarcinoma with either mouse or human fibroblasts leads to the marked reduction of ES-2 esterase titer. The extinction of ES-2 esterase activity in mouse×human hybrids is reversible. Extinction correlates with the presence of the human C10chromosome in the somatic cell hybrids; whereas reexpression of the ES-2 esterase is observed in hybrids which have lost C10. Thus, the proposed regulator element involved is probably structurally linked to C10; however, linkage to a member of the D or G groups cannot be completely excluded.

The relation of the symmetry of the thermodynamic functions with respect to the critical density ρcto the analyticity of the chemical potential above the critical temperature is discussed with the aid of thermo-dynamic considerations. Special consideration is given to the differential coefficients ([unk]2μ/[unk]T2)ρ and ([unk]2P/[unk]T2)ρ. The discussion is extended to the two-phase region, and some of the relations between critical exponents are analyzed. A proof is given that the vapor-pressure curve joins smoothly with the critical isochore. The behavior of the entropy along the coexistence curve is considered. Finally, an argument is presented that the Griffiths-Liberman inequality γ′ ≥ β(δ - 1) is an equality.

R?sum?Depuis la fin de l'invasion de la tenthr?de europ?enne de l'?pinette vers 1945, la population de cet insecte s'est maintenue ? un niveau relativement bas dans la province de Qu?bec. Une ?tude conduite de 1956 ? 1960 aux environs de la ville de Qu?bec a r?v?l? qu'aucun changement important n'est survenu dans la biologie de l'insecte et dans les facteurs naturels susceptibles de limiter sa pullulation. Les conditions de climat sont sensiblement les m?mes qu'au temps de l'invasion, et contribuent annuellement ? ?liminer une partie importante de la population au d?but du d?veloppement larvaire. Les parasites exercent une l?g?re influence et une seule esp?ce, Drino bohemicaMesn., semble s'?tre d?finitivement adapt?e dans la r?gion ?tudi?e. Les pr?dateurs au contraire continuent ? pr?lever une forte partie de la population en hivernement. La virose larvaire qui a provoqu? le d?clin de l'invasion, constitue le facteur r?gulateur et son action est particuli?rement efficace au cours de la g?n?ration estivale.

The radiolysis products from liquid CF2Cl2, CFCl3, CF2ClCF2Cl and their mixtures with bromine were analyzed by gas chromatography. The C–Cl and C–C bonds appear to be broken far more readily than the C–F bond in the γ radiolysis of these chlorofluorocarbons.

The techniques described permit the controlled production of large numbers of proliferating somatic cell hybrids in a relatively short period of time. Sendai virus is used to promote cell hybridization. ß-propriolactone is employed as the inactivating agent of Sendai virus since it produces complete loss of viral infectivity while preserving viral fusion capacity. Cells are fused in monolayer, instead of in suspension, since fixing cells in two dimensions permits one to control cell contacts during the fusion event through the expedient of varying multiplicities of the parental cells and the total cell density. Under the conditions described, a several hundred fold increase in the number of hybrid clones obtained is seen as compared to the controls.

γ-Induced hydrostannation of ethyl acrylate, allyl acetate, and vinyl acetate with triethyltin and tri-n-butyltin hydrides was attempted. The hydrostannation of ethyl acrylate and allyl acetate gave the corresponding adducts in almost quantitative yield. (2-Acetoxyethyl)-tri-n-butyltin expected from hydrostannation of vinyl acetate with tri-n-butyltin hydride could not be isolated. However, NMR and IR spectra indicated the formation of the adduct, which was found to decompose into ethylene and tri-n-butyltin acetate. The decomposition of the adduct was discussed in comparison with other adducts.

The retention indices of perhaloalkanes (perbromochlorofluoroalkanes, etc.) were measured by using a gas chromatograph with a squalane, Silicone DC 550, or Methoxy polyethylene glycol 350 column, and the correlation of the retention index with various physicochemical parameters was investigated. The retention index was found to correlate linearly with the composition of the halogen atoms in the perhaloalkane molecules; the correlation diagram appears to be of special analytical importance. The relationship between the retention index and the boiling point was also studied. The retention index was correlated linearly with the molar refractivity of the perhaloalkanes, irrespective of the polarity of the columns. The molar refractivity appears to be the inherent parameter which is most adequate for considering the regularity of the retention index. The effect of the polarity of the stationary phase on the retention index was also investigated.