Liquid-crystalline polyethers and copolyethers based on conformational isomerism, 5. Thermotropic copolyethers based on 1-(4-hydroxyphenyl)-2-(2-methyl-4-hydroxyphenyl)ethane and flexible spacers containing odd and even numbers of methylene units

The synthesis and characterization of thermotropic main-chain liquid-crystalline copolyethers based on 3-methyl-4,4′-ethylenediphenol [1-(4-hydroxyphenyl)-2-(2-methyl-4-hydroxyhenyl)-ethane (MBPE)], which is a flexible rod-like mesogenic unit or a rod-like mesogenic unit based on conformational isomerism, and pairs of flexible spacers containing odd and even numbers of methylene units, X, Y, i.e., MBPE-X/Y, where X/Y = 5/12, 5/10, 5/8, 6/11, 6/9, 4/11 and 4/9, are described. Copolymerization decreases the rate of crystallization and subsequently transforms virtual or monotropic mesophases of homopolymers into monotropic or even enantiotropic mesophases. Both liquid-crystalline transition temperatures and enthalpy changes of the identical mesophases displayed by copolymers represent weight-averaged values of the similar parameters of the parent homopolymers. Their extrapolation leads to the determination of the virtual mesomorphic transition temperatures and enthalpy changes of the parent homopolymers.     

Liquid-crystalline polyethers and copolyethers based on conformational isomerism, 4. Thermotropic polyethers and copolyethers based on 1-(4-hydroxyphenyl)-2-(2-methyl-4-hydroxyphenyl)ethane and flexible spacers containing an even number of methylene units

The synthesis and characterization of thermotropic main-chain liquid-crystalline polyethers MBPE-X and copolyethers MBPE-X/Y based on 3-methyl-4,4′-ethylenediphenol [1-(4-hydroxyphenyl)-2-(2-methyl-4-hydroxyphenyl)ethane (MBPE)], which is flexible rod-like mesogenic unit or a rod-like mesogenic unit based on conformational isomerism, and flexible spacers containing an even number of methylene units, X, Y, are described. The particular examples presented in this paper refer to polyethers MBPE-4, MBPE-6, MBPE-8, MBPE-10, and MBPE-12, and copolyethers MBPE-X/Y; where X,Y = 4, 6, 8, 10, 12. MBPE-4, MBPE-6, MBPE-10 and MBPE-12 are crystalline. MBPE-8 displays an enantiotropic nematic mesophase. Copolymerization of MBPE with different pairs of spacers containing even numbers of methylene units leads to MBPE-X/Y copolymers displaying monotropic or enantiotropic nematic mesophases. Both liquid-crystalline transition temperatures and the corresponding enthalpy changes of the copolymers represent weight-averaged values of the similar parameters of the parent homopolymers. Extrapolation of the isotropic-nematic and nematic-isotropic transition temperatures and their corresponding enthalpy changes demonstrated that all homopolymers containing an even number of methylene units in the flexible spacer exhibit virtual nematic mesophases. The virtual isotropic-nematic transition temperatures and the corresponding enthalpy changes were determined for MBPE-4, MBPE-6, MBPE-10 and MBPE-12. The virtual nematic-isotropic transition and the corresponding enthalpy changes could be determined only for MBPE-10 and MBPE-12.     

Synthesis of simple main-chain type polyimides derived from aliphatic diamines and 4,4″-terphenyltetracarboxylic acid,and their thermotropic liquid crystalline behavior

We have synthesized a series of aliphatic-aromatic polyimides by high pressure polycondensation of monomer salts derived from diaminoalkanes and diethyl 4,4″-terphenyl-tetracarboxylates. The polyimides, designated as P-nTPE, were obtained with n, the number of methylene units in the spacer, ranging from 6 to 12. Among these, the P-nTPE polyimides with 8?n?12 from mesophases. The mesophases of P-8TPE and P-11TPE are enantiotropic, whereas those of the other polyimides are monotropic. The nematic phase was identified for all polyimides from X-ray and microscopic observations; only P-11TPE exhibits polymorphism, in which a nematic phase is followed by a smectic phase upon cooling. The ability for liquid crystal formation in main-chain polyimides is discussed.     

Synthesis and Properties of Side‐Chain Liquid Crystalline Polypeptides Bearing Various Alkyl Spacers and Oligo‐Ethylene‐Glycol Tails

A series of polypeptides bearing various alkyl (i.e., propyl, hexyl, or octyl) spacers, biphenyl mesogens, and oligo‐ethylene‐glycol (OEG) tails (i.e., PPLG₂₆‐BPOEG _m, PHLG₃₄‐BPOEG_m, and POLG₃₂‐BPOEG_m [m = 3 or 7]) has been synthesized via 1,3‐dipolar cycloaddition reactions with quantitative grafting densities. Fourier transform infrared results reveal that the polypeptides adopted an α‐helical conformation in the solid‐state. Differential scanning calorimetry (DSC) analysis reveals that the glass transition temperatures (T_gs) of the polypeptides with OEG₃ tails decrease with the increasing length of the alkyl spacers. For the samples containing alkyl spacers of the same length, T_g significantly decreases with the increasing lengths of the OEG tails. Polarized optical microscope (POM) results reveal that all polypeptides exhibit strong birefringence at room temperature. Polypeptides with long alkyl spacers (i.e., hexyl or octyl) or OEG₇ tails show isotropic transitions, while PPLG₂₆‐BPOEG₃ show no clear point temperature before thermal decomposition. DSC, POM, and wide‐angle X‐ray scattering results collectively reveal that polypeptides with long alkyl spacers (i.e., hexyl or octyl) and OEG₃ tails undergo a reversible smectic E phase to isotropic phase transition, while polypeptides with OEG₇ tails undergo a reversible liquid crystalline phase to isotropic phase transition. The transition temperatures increase with the increasing length of alkyl spacers.

     

Semiflexible main-chain liquid crystal polymers — the influence of the chemical structure on liquid crystalline properties

Two new homologous series of semiflexible main-chain polyesters on the basis of 4-hydroxy-and 4-carboxycinnamic acid in conjugation with 2-tert-butylhydroquinone and alkylene spacers with 3 to 8 methylene groups were prepared by low-temperature solution condensation. The thermotropic properties were investigated by means of differential scanning calorimetry, polarising microscopy and X-ray diffraction analysis. The differences in enantiotropic behaviour and thermal stability of the mesophases influenced by the two different linkage groups between alkylene spacer and rigid moiety are discussed in comparison to related systems known from the literature.     

Mesomorphism — structure relationships in polyesters based on twin p-oxybenzoate mesogens

Three homologous series of semiflexible polyesters constituted by twin spaced p-oxybenzoyl diads were studied with respect to their mesomorphic behaviour as a function of the relative length of the two different spacers [oligo(oxyethylene) and polymethylene] connected in an alternating fashion in the repeating unit. Within each series the oligo(oxyethylene) segment was maintained constant (n = 2, 3, 4), whereas the polymethylene segment varied in steps of one methylene unit from pentamethylene to decamethylene (m = 5 to 10). Indications are gained of how the parity of both ether and hydrocarbon spacers may affect the phase diagrams of the samples. The parity of the oligo(oxyethylene) segments appears in particular very effective in maximizing the orientational correlation between the mesogenic p-oxybenzoyl diads.     

Synthesis of novel sulfonyl-containing liquid-crystalline side-chain poly(vinyl ethers)

The synthesis of some new liquid-crystalline polymers with sulfonyl-containing mesogenic groups is described. 4-[(S)-(-)-2-MethylbutyIsulfonyl]-4′-[(11-vinyloxy)undecyloxy]biphenyl ( 10 -11), 4-[(S)-(-)-2-methylbutylsulfonyl]-4′-[8-(vinyloxy)octyloxy]biphenyl ( 10 -8), 4-[(S)-(-)-2- methylbutylsulfonyl]biphenyl 4-[11-(vinyloxy)undecyloxy]benzoate ( 12 -11), 4-[(S)-(-)-2-methylbutylsulfonyl]biphenyl 4-[8-(vinyloxy)octyloxy]benzoate ( 12 -8), 4-[(S)-(-)-2-methylbutyloxy]-4′- [11-(vinyloxy)undecylsulfonyl]biphenyl ( 18 -11) and 2-[11-(vinyloxy)undecyloxy]-6-{4-[(S)-(-)-2- methylbutylsulfonyl]phenyl}naphthalene ( 23 -11) were all synthesized, and polymerized with the initiating system CF₃SO₃H/S(CH₃)₂ in CH₃Cl₃ at 0°C. Monomers 10 -11, 10 -8, 18 -11 and 23 -11 are crystalline, while both 12 -11 and 12 -8 show an enantiotropic smectic A phase. All polymers exhibit the same thermotropic behaviour as their corresponding monomers, except poly( 23 -11) which exhibits an enantiotropic smectic A (s_A) and a monotropic chiral smectic C phase (S*_C).     

Phase structures,transition behavior and surface alignment in polymers containing rigid rod-like backbones with flexible side chains, 3. The even-odd effect on phase transitions in combined liquid crystal polyesters

A series of "combined" liquid crystal (LC) polyesters consisting of aromatic main-chain backbones and flexible aliphatic side chains with 4-cyanobiphenyl end groups was synthesized based on the polycondensation of 2,2′-bis(trifluoromethyl)-4,4′-biphenyldicarbonyl chloride with 2,2′-bis{ω-[4-(4-cyanophenyl)phenoxy]-n-alkoxycarbonyl]}-4,4′-biphenyldiol (PEFBP). In a recent study of PEFBP(n = 11) containing eleven methylene units in the side chains, four different phases were identified in addition to the isotropic melt (I). They are as follows: an orthorhombic crystalline (K_O) phase, two triclinic crystalline (K_T1 and K_T2) phases in the high temperature region, and a nematic (N) phase. In this report, we focus on the even-odd effect of the methylene units in the side chains on the phase structure and transition behavior of PEFBP(n = 8, 9, 10 and 11)s. Two even-numbered PEFBPs with either eight or ten methylene units in the side chains [PEFBP(n = 10 and 8)s] were studied. An odd-numbered PEFBP containing nine methylene units, PEFBP(n = 9), was also investigated in addition to PEFBP(n = 11) which was reported on previously. It was found that both of the PEFBPs with even-numbered methylene units in their side chains [PEFBP(n = 10 and 8)s] exhibit only a nematic and a smectic A (S_A) phase. Their phase transition sequence during heating and cooling is T_g (S_A LC glass) ↔ S_A ↔ N ↔ I Since only LC phases exist, this is a thermodynamically reversible transition sequence independent upon thermal history. For PEFBP(n = 9 and 11)s, crystalline phases with three-dimensional order are observed above the NLC glass transition temperature in addition to the N phase. In PEFBP(n = 9), the N and K_O phases are similar to those seen in the case of PEFBP(n = 11). However, this polymer presents only one triclinic crystalline phase, while two triclinic crystal phases are observed in PEFBP(n = 11). The phase transition sequence in these odd-numbered PEFBPs during heating between 2.5°C/min –10°C/min for a sample cooled from the isotropic melt at the same rate is T_g (N LC glass) → K_O → N → K_T(s) → N → I Nevertheless, this sequence does not represent a case of thermodynamic equilibrium. The K_O and K_T(s) phases in PEFBP(n = 9 and 11)s and the S_A phase in PEBFP(n = 8 and 10)s are characteristics of the even-odd effect observed in this series of combined LC polyesters. The number of methylene units in the side chains thus plays a critical role in the formation of phase order and transition behavior in a way quite different from the common even-odd effect seen in main-chain LC polymers. Furthermore, this effect also indicates that the 4-cyanobiphenyl groups in the side chains are incorporated with the main-chain backbones to form the liquid crystal and crystal phases.     

Recurrent copy number alterations in low‐grade and anaplastic pleomorphic xanthoastrocytoma with and without BRAF V600E mutation

Pleomorphic xanthoastrocytoma (PXA) is a rare localized glioma characterized by frequent BRAF V600E mutation and CDKN2A/B deletion. We explored the association of copy‐number variants (CNVs) with BRAF mutations, tumor grade, and patient survival in a cohort of 41 PXA patients using OncoScan chromosomal microarray. Primary resection specimens were available in 38 cases, including 24 PXA and 14 anaplastic PXA (A‐PXA), 23 BRAF V600E mutant tumors (61%). CNVs were identified in all cases and most frequently involved chromosome 9 with homozygous CDKN2A/B deletion (n = 33, 87%), a higher proportion than previously detected by comparative genomic hybridization (50%–60%) (37). CDKN2A/B deletion was present in similar proportion of PXA (83%), A‐PXA (93%), BRAF V600E (87%), and wild‐type (87%) tumors. Whole chromosome gains/losses were frequent, including gains +7 (n = 15), +2 (n = 11), +5 (n = 10), +21 (n = 10), +20 (n = 9), +12 (n = 8), +15 (n = 8), and losses −22 (n = 11), −14 (n = 7), −13 (n = 5). Losses and copy‐neutral loss of heterozygosity were significantly more common in A‐PXA, involving chromosomes 22 (P = 0.009) and 14 (P = 0.03). Amplification of 8p and 12q was identified in a single tumor. Histologic grade was a robust predictor of overall survival (P = 0.003), while other copy‐number changes, including CDKN2A/B deletion, did not show significant association with survival. Distinct histologic patterns of anaplasia included increased mitotic activity in an otherwise classic PXA or associated with small cell, fibrillary, or epithelioid morphology, with loss of SMARCB1 expression in one case. In 10 cases, matched specimens were compared, including A‐PXA with areas of distinct low‐ and high‐grade morphology (n = 2), matched primary/tumor recurrence (n = 7), or both (n = 1). Copy‐number changes on recurrence/anaplastic transformation were complex and highly variable, from nearly identical profiles to numerous copy‐number changes. Overall, we confirm CDKN2A/B deletion as key a feature of PXA not associated with tumor grade or BRAF mutation, but central to the underlying genetics of PXA.     

Crystallinity of methylene-oxyethylene-methylene triblock oligomers derived from pentadeca(ethylene glycol)

Block oligomers of the general formula CH₃(CH₂)_nO[CH₂CH₂O]₁₅(CH₂)_nCH₃ where n + 1 = n_c = 1 to 18 and 21 have been prepared. Both the oxyethylene and the methylene blocks are monodisperse. Examination of their crystallinity (by differential scanning calorimetry (DSC); X-ray scattering; IR, Raman, and ¹H NMR spectroscopy) shows two important structures I and II. I: 3 ? n_c ? 6: oxyethylene blocks crystalline, methylene blocks non-crystalline; II: 13 ? n_c ? 18: oxyethylene and methylene blocks crystalline. Samples with n_c = 1 or 2 crystallise essentially as poly(oxyethylene). Samples with 7 ? n_c ? 12 are intermediate in structure between I and II. Structure II has 7/2 helical oxyethylene blocks in high density crystalline layers, with a structure closely related to that of monoclinic poly(oxyethylene), and planar zig-zag methylene blocks in low density crystalline layers. The oxyethylene helices are normal to the lamella end-planes, or almost so, and the methylene planar zig-zags are tilted. The enthalpies of fusion of the type II block oligomers show an even-odd effect. There is evidence of chain folding in the block oligomer with n_c = 21.     

Schutz zellfremder DNA vor wirtskontrollierter Restriktion in Bakterienzellen. II. Schutz des Plasmids pSF2124 durch die ocr+ Genfunktion der Bakteriophagen T3 und T7

When restriction-active Escherichia coli cells (rm) are transformed with the pSF2124 plasmid, a common vector in experimental gene transfer, the efficiency of transformation (e.o.t.) is lowered by 2 orders of magnitude compared with restriction-negative (rm or rm) recipient cells due to restriction of the pSF2124 DNA by endoR.EcoP1. Preinfection of rm cells with UV-inactivated ocr⁺ phages (T3, T7, T3sam^?) still able to express their early genes protects the plasmid DNA against restriction by endoR.EcoP1: The e.o.t. of rm recipient cells with pSF2124 attains the same high value as that of r^?m^? cells. The specific role of the ocr⁺ gene function was demonstrated by the use of ocr^? mutants (T3/R7, T7/ D111): Preinfection with such phage mutants does not increase the e.o.t. of rm cells. An unspecific e.o.t. alteration of restriction-negative (r^?m^?) recipient cells by ocr⁺ or ocr^? phages was excluded. The ocr^? gene function can be exploited to protect pSF2124 against DNA restriction. The recipient cells survive the process of phage preinfection and transformation and stably replicate themselves as well as the plasmid DNA.     

Crystal structure and mesophase morphology of MBPE polyethers containing odd-number methylene spacers

A series of polyethers was synthesized from 4-[2-(4-hydroxyphenyl)ethyl]-3-methylphenol and α, ω-dibromoalkenes, MBPE-n. The polymers with odd-numbered methylene spacers show a monotropic mesophase behavior during cooling from the isotropic melt before crystallization. The crystal structures of MBPE (n = odd) polyethers have been investigated through wide angle X-ray diffraction fiber patterns. Two crystallographic periods along the c-axis are found, one of which corresponds to the length of methylene spacers, and the other is close to an integral number times the length of the repeating unit. Polarized light microscopy observations of the uniaxially oriented samples obtained through mechanical shear show a banded texture, which is a typical morphology found in liquid crystal polymers. Transmission electron microscopy experiments provide morphological evidence to identify that this mesophase is a nematic liquid crystal state based on the disclination defect patterns defined by Frank. A relationship between splay elastic constant k₁₁ and bend elastic constant k₃₃ is discussed through lamellar decoration of disclination defects.     

Chromosomal aberrations associated with invasion in papillary superficial bladder cancer

Non-invasive and invasive papillary transitional cell carcinomas of stages pTa and pT1 represent the first steps of tumour progression in bladder cancer. In order to analyse different chromosomal alterations of pTa and pT1 superficial bladder cancer, 46 tumour specimens were examined by comparative genomic hybridization (CGH). Losses of chromosome 9 material (11/20) and gains of chromosome 17 material (6/20) were frequently found in pTa tumours. Stage pT1 tumours were characterized by gains of chromosome 1q (14/26; including amplification at 1q21–q24 in three cases) and chromosome 17 material (15/26), as well as by losses of 11p (15/26) and 11q (13/26). Other loci frequently showing losses in pT1 tumours were 2q (9/26), 4q (10/26), 5q (9/26), 8p (10/26), 9p (9/26), 9q (12/26), 10q (8/26), 17p (7/26), and 18q (8/26). Amplifications were detected at 8q21/22, 5q21, 7q36, 10p14, 10p12, 10q25, 12q12, and 12q14. The most striking differences between grade 2 pTa and pT1 tumours were gains of 1q (P<0·01) and losses at 2q (P<0·025), 10q (P<0·05), 11p (P<0·01), 11q (P<0·01), and 17p (P<0·05), as well as the total number of aberrations (pTa grade 2: 4·1; pT1 grade 2: 8·6 aberrations per tumour). These data show characteristic chromosomal aberrations associated with invasion in superficial bladder cancer. © 1998 John Wiley & Sons, Ltd.     

T cell receptor Vβ repertoire in mice lacking endogenous mouse mammary tumor provirus

When endogenous mouse mammary tumor virus (MMTV) superantigens (SAg) are expressed in the first weeks of life an efficient thymic deletion of T cells expressing MMTV SAg-reactive T cell receptor (TcR) Vβ segments is observed. As most inbred mouse strains and wild mice contain integrated MMTV DNA, knowing the precise extent of MMTV influence on T cell development is required in order to study T cell immunobiology in the mouse. In this report, backcross breeding between BALB.D2 (Mtv-6, ?7, ?8 and ?9) and 38CH (Mtv^?) mice was carried out to obtain animals either lacking endogenous MMTV or containing a single MMTV locus, i.e. Mtv-6, ?7, ?8 or ?9. The TcR Vβ chain (TcR Vβ) usage in these mice was analyzed using monoclonal antibodies specific for TcR Vβ2,Vβ3, Vβ4,β5,Vβ6,Vβ7,Vβ8,Vβ11,Vβ12 and Vβ14 segments. Both Mtv-8⁺ mice and Mtv-9⁺ mice deleted TcR Vβ5⁺ and Vβ11⁺ T cells. Moreover, we also observed the deletion of TcR Vβ12⁺ cells by Mtv-8 and Mtv-9 products. Mtv-6⁺ and Mtv-7⁺ animals deleted TcR Vβ3⁺ and Vβ35⁺ cells, and TcR Vβ6⁺,Vβ7⁺ and Vβ8.1⁺ cells, respectively. Unexpectedly, TcR Vβ8.2⁺ cells were also deleted in some backcross mice expressing Mtv-7. TcR Vβ8.2 reactivity to Mtv-7 was shown to be brought by the 38CH strain and to result from an amino acid substitution (Asn → Asp) in position 19 on the TcR Vβ8.2 fragment. Reactivities of BALB.D2 TcR Vβ8.2 and 38CH TcR Vβ8.2 to the exogenous infectious viruses, MMTV(SW) and MMTV(SHN), were compared. Finally, the observation of increased frequencies of TcR Vβ2⁺, Vβ4⁺ and Vβ8⁺ CD4⁺ T cell subsets in Mtv-8⁺ and Mtv-9⁺ mice, and TcR Vβ4⁺ CD4⁺ T cells in Mtv-6⁺ and Mtv-7⁺ mice, when compared with the T cell repertoire of Mtv^? mice, is consistent with the possibility that MMTV products contribute to positive selection of T cells.     

Synthesis of Amorphous Hydrophobic Telechelic Hydrocarbon Diols via ADMET Polymerization

Amorphous, hydrophobic telechelic hydrocarbon diols were synthesized using acyclic diene metathesis (ADMET) polymerization. These diols can be used in hydrolysis and UV resistant polyurethanes. The hydrocarbon backbone is based on a mimic of an ethylene/isobutylene polymer, made by the ADMET polymerization of a gem‐dimethyl substituted α,ω‐diene followed by hydrogenation of the polymer's repeat unit unsaturation. Chain termination reactants (CTR's) having one, three, and nine methylene “spacers,” respectively, between their olefin and alcohol precursor group were used to cap the polymer chain ends to yield 2.0 functional telechelics. Use of the medium length CTR in a polymerization–depolymerization scheme, resulted in amorphous (T_g = ?56 °C) telechelic diols with good molecular weight control.

     

Copolymerization of styrene with Zn(II), Co(II), Ni(II) and Cu(II) acrylates

The radical copolymerization of styrene with Zn(II), Co(II), Ni(II) and Cu(II) acrylates in methanol at 60°C was studied and that of styrene with Cu(II) acrylate also in acetonitrile at 80°C. In a given period of time an increase of conversion was observed with increasing concentration of the first three metal acrylates in mixtures with styrene. With Cu(II) acrylate, however, a decrease of conversion was found. The monomer reactivity ratios were determined as follows: r_St = 1,10, r = 0,90; r_St = 1,74, r = 0,56; r_St = 1,83, r = 0,53; r_St = 5,94, r = 0,12 (in acetonitrile). The products of the reactivity ratios, almost equal to one, reflect an “ideal” copolymerization and therefore a very little alternating tendency in propagation reactions. The Alfrey-Price Q-e parameters for the metal acrylates were calculated and discussed.     

Characterization and kinetics of mesophase transition for naphthalene-based thermotropic polyesters with polymethylene spacers

Main-chain thermotropic polyesters containing naphthalene rings and flexible spacers with 2 ≤ n ≤ 10 methylene groups were prepared in this study. Their thermotropic properties were investigated by means of differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The nematic mesophase dominates the anisotropy of the prepared polymers except for the polymers with n = 7 and n = 9. Moreover, the nematic domain size depends upon the number n. On the other hand, the naphthalene ring in the mesogen has a strong effect on the mesomorphic properties of the prepared polyesters. The polymers with n = 7 and n = 9 exhibit cooling rate-dependent anisotropic behavior of nematic and smectic phases. The crystallization for the investigated polymers is strongly influenced by the anisotropic behavior. The kinetics of crystallization at higher temperatures does not satisfy the Ozawa theory, while it does at lower temperatures. Nucleation begins to occur in the nematic shreads and the crystal growth proceeds toward liquid-crystalline domains from the observation by POM. Thus, the Avrami exponent a is dependent upon the polymethylene spacer with n being even or odd and high or low. In addition, the parameters of crystallization obtained from DSC and X-ray diffraction were consistent with the results of non-isothermal crystallization kinetics and the observation by POM.     

Fine‐mapping scan of bipolar disorder susceptibility loci in Latino pedigrees

We previously identified bipolar disorder (BD) susceptibility loci on 8q24, 14q32, and 2q12‐14 in a genome‐wide nonparametric linkage screen in a Latino cohort. We now perform a fine mapping analysis using a dense map of additional SNPs to identify BD susceptibility genes within these regions. One thousand nine hundred and thirty‐eight individuals with Latino ancestry (880 individuals with BD Type I or Schizoaffective, Bipolar Type) from 416 Latino pedigrees from the United States, Mexico, Costa Rica, and Guatemala were genotyped with 3,074 SNPs to provide dense coverage of the 8q24 (11.5 cM), 14q32 (7.5 cM), and 2q12‐14 (6.5 cM) chromosomal loci. Single‐marker association tests in the presence of linkage were performed using the LAMP software. The top linkage peak (rs7834818; LOD = 5.08, p = 3.30E ? 5) and associated single marker (rs2280915, p = 2.70E ? 12) were located within FBXO32 on 8q24. On chromosome 2, the top linkage peak (rs6750326; LOD = 5.06, p = 3.50E ? 5) and associated single marker (rs11887088, p = 2.90E ? 6) were located in intragenic regions near ACTR3 and DPP10. None of the additional markers in the region around chromosome 14q32 met significance levels for linkage or association. We identified six SNPs on 2q12‐q14 and one SNP in FBXO32 on 8q24 that were significantly associated with BD in this Latino cohort.     

Enzymatic Synthesis and Chemical Recycling of Polythiocaprolactone

High‐molecular‐weight polythiocaprolactone (PTCL) was prepared in a green process via lipase‐catalyzed ROP of a cyclic 6‐mercaptohexanoic acid (6MH) oligomer. PTCL was readily depolymerized by lipase to cyclic 6MH in dilute toluene solution, which was then readily repolymerized by the same lipase to produce PTCL with the same $\overline {M} _{{\rm w}} $ as the initial PTCL in a chemical recycling process. The T_m of PTCL was higher than that of the corresponding PCL. A P(TCL‐co‐CL) copolymer with 60 mol‐% TCL (6MH) units showed a higher T_m as the PCL homopolymer. Similar apparent K_m values were obtained for the cyclic 6MH oligomers and caprolactone oligomers, however, the V_max of cyclic 6MH oligomers was significantly lower than that of the corresponding caprolactone oligomers.

     

The characterization of VP7 (G type) and VP4 (P type) genes of bovine group A rotaviruses from field samples using RT-PCR and RFLP analysis

Summary Characterization of the VP7 (G type) and VP4 (P type) genes of bovine group A rotaviruses (BRV) from field samples was performed using RT-PCR and RFLP analysis. After RT-PCR amplification of the full length VP7 genes and partial length VP4 genes (nucleotides 1 to 1096), four enzymes,EcoRV,NlaIV,BamHI andHpaII were used for digestion analysis. For VP7, four RFLP profiles were observed after analysis of the digests: they were designated as G6, G6s (subtype, showed about 86% nucleotide and 90% amino acid identity to reference G6 strains), G8 and G10. For VP4, three RFLP profiles were observed: designated as P[1], P[5] and P[11].The G typing analysis of 86 BRV fecal samples from 5 states, representing at least 11 different herds revealed that 60.5% (52/86) were G6, which included G6s (9/52); 19.8% (17/86) were G10; 7% (6/86) were G8; 10.4% (9/86) were G6 and G10 mixtures including two G6s samples; and 2.3% (2/86) were G6 and G6s mixtures. The P typing analysis of the same 86 fecal samples revealed that 64% (55/86) were P[5]; 28% (24/86) were P[11]; 1.2% (1/86) were P[1] and 6 samples (7%) were mixtures of either P[11] or P[5]. When the same samples were analyzed according to G and P type specificity, all possible combinations of G and P types existed in the field. The G6P[5] type was most prevalent and accounted for 46.7% (41/86) of the samples; 12.8% (11/86) were G10P[11]; 7% (6/86) were G10P[5] and an equal number were G6sP[11]. The G6P[11] (n=2), G8P[1] (n=1), G8P[5] (n=1) and G8P[11] (n=3) combinations were also observed. The following mixed BRV infections were observed in the field samples; G6sP[5+11] (n=1), G8P[5+11] (n=1), G6+G10P[5] (n=1) G6+G10P[5+11] (n=2), G6+G6sP[11] (n=1), G6+G6sP[1+11] (n=1), G6s+G10P[11] (n=1) and G6s+G10P[5+11] (n=1). Information on the G and P types and G/P combinations in the field samples should be useful for understanding the epidemiology of BRV and designing vaccination strategies to control BRV in the field.