“Inorganic and Organometallic Clusters and Polymers: Syntheses and Applications” Symposium

Conference Reports: This section contains reports on topical conferences. Reports are usually written at the request of the editorial office, but unsolicited contributions are also welcome. Suggestions should be sent to the editorial office of the Macromolecular journals, preferably by E‐mail to macromol@wiley‐vch.de.     

Polymer Reaction Engineering VI Halifax,Canada May 21–26, 2006

Conference Reports: This section contains reports on topical conferences. Reports are usually written at the request of the editorial office, but unsolicited contributions are also welcome. Suggestions should be sent to the editorial office of the Macromolecular journals, preferably by E‐mail to macromol@wiley‐vch.de.     

IUPAC International Symposium on Ionic Polymerization Goa,India, IP2005, October 23–28, 2005

Conference Reports: This section contains reports on topical conferences. Reports are usually written at the request of the editorial office, but unsolicited contributions are also welcome. Suggestions should be sent to the editorial office of the Macromolecular journals, preferably by E‐mail to macromol@wiley‐vch.de.     

Metal‐ and Metalloid‐Containing Macromolecules Symposium

Conference Report: This section contains reports on topical conferences. Reports are usually written at the request of the editorial office, but unsolicited contributions are also welcome. Suggestions should be sent to the editorial office of the Macromolecular journals, preferably by E‐mail to macromol@wiley‐vch.de.     

16th Polymer Networks Group Meeting

This section contains reports on topical conferences. Reports are usually written at the request of the editorial office, but unsolicited contributions are also welcome. Suggestions should be sent to the editorial office of the Macromolecular journals, preferably by E‐mail to macromol@wiley‐vch.de.     

Missions and Challenges of Polymer Science and Technology

This section contains reports on topical conferences. Reports are usually written at the request of the editorial office, but unsolicited contributions are also welcome. Suggestions should be sent to the editorial office of the Macromolecular journals, preferably by E‐mail to macromol@wiley‐vch.de .     

The “Ins” and “Outs” of the Depressive Disorders Section of DSM‐5

In this article, we review and evaluate changes in the depressive disorders section from DSM‐IV to DSM‐5. We describe characteristics of three new depressive disorders: disruptive mood dysregulation disorder, premenstrual dysphoric disorder, and persistent depressive disorder. We also discuss the controversial decision in DSM‐5 to remove the bereavement exclusion from the criteria for major depressive disorder. Next, we review the decision to replace the diagnosis of depressive disorder not otherwise specified with two new diagnoses: other specified depressive disorder and unspecified depressive disorder. Finally, we discuss the inclusion of two novel specifiers in the DSM‐5 depressive disorders section: “with anxious distress” and “with mixed features.” For each of these changes, we examine the relevant research and discuss implications of the changes for research and clinical practice.     

Synthesis and Characterization of Ethylene/1‐Olefin Copolymers Obtained by “Single Centre” Catalysis

The catalytic system rac‐Me₂Si(Ind)₂ZrCl₂/MAO was used to polymerize ethylene and to copolymerize ethylene with different 1‐olefins (copolymers containing 1‐olefins up to 1‐tetradecene were prepared). In the presence of the 1‐olefin, the catalytic activity increases. As expected, the amount of 1‐olefin inserted in the polymer chain depends on the monomers molar ratio in the polymerization bath. The molecular weight of the copolymer decreases as the concentration of the 1‐olefin increases owing to the relatively easy chain transfer reactions after primary and secondary 1‐olefin insertions and the effect depends on the length of the 1‐olefin. The average ethylene sequence length decreases as the amount of inserted 1‐olefin increases leading to a decrease of the melting temperature, T_m. The crystallinity of polymers with the same 1‐olefin content seems to be lower increasing the length of the 1‐olefin. The comonomer distribution is not influenced by the 1‐olefin length but depends only on the catalytic system.     

Short Portrait of Prof. Dr. Oskar Nuyken on the Occasion of his 65th Birthday

This section contains news of the macromolecular community all over the world. Articles about, for example, people, projects, and market trends are welcome. Suggestions should be sent to the editorial office of the Macromolecular journals, preferably by E‐mail to macromol@wiley‐vch.de. The editorial office decides which articles will be published.     

“Living” free radical ring‐opening polymerization of 2‐methylene‐4‐phenyl‐1,3‐dioxolane by atom transfer radical polymerization

The “living” free radical ring‐opening polymerization of 2‐methylene‐4‐phenyl‐1,3‐dioxolane (MPDO) in the presence of ethyl α‐bromobutyrate/CuBr/2,2′‐bipyridine at various temperatures has been investigated. In comparison with the conventional ring‐opening polymerization of MPDO, a lower content of ring‐opened unit in the polymer was found. The results of ln[M]₀/[M]) against polymerization time, (M_n)_th and (M_n)_NMR vs conversion, and GPC of the polymers are strongly indicative of the “living” polymerization process. Initiator efficiency was measured. The mechanism of polymerization, and the effect of pyridine on the polymerization mechanism were discussed.     

High frequency of false‐positive signals in a real‐time PCR‐based “Plus/Minus” assay

Molecular biological methods using real‐time polymerase chain reaction (RT‐PCR) for detection of bacterial and viral genes in different environments have been developed into assays from different commercial sources. Applied Biosystems include and support two applications with their TaqMan instrument: the “Plus/Minus” and the “Allelic Discrimination” assays. These approaches are RT‐PCR based, use short primers and fluorescent‐labeled TaqMan probes and include three processes: a pre‐read run, a PCR‐amplification run, and a post‐read run. In the “Plus/Minus” assay, samples and controls (distilled water) are loaded into the instrument, which calculates a positive or a negative outcome based on differences in signals between samples and the controls. When testing the “Plus/Minus” assay for detection of usp genes encoding a uropathogenic specific protein in Escherichia coli, an inordinately high proportion of false‐positive signals was observed. This was shown to be due to a serious methodological deficiency. Our observations indicate that an adequate no‐template control closely matching the target samples in all aspects, including amount of DNA, is required to establish a correct threshold in the pre‐read run that forms the basis for further calculations in the post‐read run of the “Plus/Minus” assay.     

Intrafamilial “DOA‐plus” phenotype variability related to different OMI/HTRA2 expression

Dominant Optic Atrophy and Deafness (DOAD) may be associated with one or more of the following disorders such as myopathy, progressive external ophthalmoplegia, peripheral neuropathy, and cerebellar atrophy (“DOA‐plus”). Intra‐ and interfamilial variability of the “DOA‐plus” phenotype is frequently observed in the majority of the patients carrying the same mutation in the OPA1 gene. We are describing two familial cases of “DOA‐plus” carrying the same c.1334G>A (p.Arg445His) mutation in OPA1 and disclosing different clinical, pathological and biochemical features. The two patients showed different expression levels of the mitochondrial OMI/HTRA2 molecule, which acts as a mitochondrial stress sensor and has been described to interplay with OPA1 in in vitro studies. Our data offer the cue to inquire the role of OMI/HTRA2 as a modifier gene in determining the “DOAplus” phenotype variability.     

LTBP2‐related “Marfan‐like” phenotype in two Roma/Gypsy subjects with the LTBP2 homozygous p.R299X variant

Recessive variants in LTBP2 are associated with eye‐restricted phenotypes including (a) primary congenital glaucoma and (b) microspherophakia/megalocornea and ectopia lentis with/without secondary glaucoma. Nosology of LTBP2 pathology in humans is apparently in contrast with the consolidated evidence of a wide expression of this gene in the developing embryo. Accordingly, in previously published patients with LTBP2‐related eye disease, additional extraocular findings have been occasionally reported and include, among others, high‐arched palate, tall stature, and variable cardiac involvement. Anyway, no emphasis was put on such systemic manifestations. Here, we report two unrelated Roma/Gypsy patients first ascertained for a multisystem disorder mainly characterized by primary congenital glaucoma, complex congenital heart defect, tall stature, long fingers, skin striae and dystrophic scarring, and resembling Marfan syndrome. Heart involvement was severe with polyvalvular heart dysplasia in one, and transposition of great arteries, thoracic arterial tortuosity, polyvalvular heart dysplasia, and neo‐aortic root dilatation in the other. Both patients were homozygous for the recurrent c.895C>T[p.(R299X)] variant, typically found in individuals of Roma/Gypsy descent with an eye‐restricted phenotype. Our findings point out LTBP2 as responsible of a systemic phenotype coherent with the community of syndromes related to anomalies in genes involved in the TGFβ‐pathway. Among these disorders, LTBP2‐related systemic disease emerges as a distinct condition with expanding prognostic implications and autosomal recessive inheritance.     

Ethylene/4‐Methyl‐1‐pentene Copolymers by a “Constrained Geometry Catalyst”: Advances in 13C NMR Assignment

Ethylene/4‐methyl‐1‐pentene (E/4M1P) copolymers were synthesized by [Me₂Si(η₅‐Me₄C₅)‐(η₁‐N‐^tBu)TiCl₂] and methylalumoxane (MAO) catalyst ( CG ) and analyzed by ¹³C NMR. The low regio‐ and stereoregularity of CG leads to spectral multiplicities which can be ascribed not only to differences in comonomer sequences but also to the presence of regio‐ and stereoirregularities. The tendency of CG to give a nearly random comonomer distribution gives rise to so far undetectable alternating sequences. The complete set of assignments proposed allows a satisfactory characterization of variously microstructured E/4M1P copolymers and the evaluation of the amount of regioirregular sequences in addition to the full determination of dyad and triad copolymer composition.

     

N‐Acylisoindigo Derivatives as Polymer Acceptors for “All‐Polymer” Bulk‐Heterojunction Solar Cells

Polymer acceptors are a class of “non‐fullerene” electron‐transporting materials that can replace [6,6]‐phenyl C61/71 butyric acid (PC61/71BM) in bulk‐heterojunction (BHJ) solar cells. In this contribution is reported the use of N‐acyl‐substituted isoindigo (IID) motifs (IID(CO)) as electron‐deficient units in the design of polymer acceptors for “all‐polymer” BHJ solar cells. While IID motifs are commonly used in the design of polymer donors for efficient BHJ solar cells with the fullerene PC61/71BM acceptors, here it is shown that IID(CO) building units used in conjunction with suitable co‐monomers represent a practical avenue for polymer acceptors with electron affinity values comparable to that of PC61/71BM (i.e., 4.2 eV).     

Ethylene Polymerization with “Constrained‐Geometry” Titanium Catalysts over Borate‐Modified Silica Supports

Two different mesoporous silica materials, Sylopol® 948 and MPS5, were used as substrates for the preparation of silica‐bound trityl tris(pentafluorophenyl)borate activators. The borate‐modified silica supports, B‐Sylopol and B‐MPS5, were characterized by solid‐state NMR spectroscopy and ICP mass spectrometry, and applied as activators for slurry polymerization of ethylene using “constrained‐geometry” titanium complexes of the formula Ti(η⁵ : η¹‐C₅Me₄SiMe₂NR)X₂ (R = Me, ⁱPr, ^tBu; X = Me, Bz, Cl) in the presence of triisobutylaluminium (TIBA). The activity of the B‐Sylopol system was higher than that of the corresponding homogeneous catalysts Ti(η⁵ : η¹‐C₅Me₄SiMe₂NR)X₂/Ph₃C⁺ [B(C₆F₅)₄]^–, whereas that of the B‐MPS5 system was lower. These supported catalysts produced polyethylenes with higher molecular weights (M̄_w in the range of 10⁶), narrower molecular weight distributions (M̄_w/M̄_n = 1.5–2.3) and higher bulk densities (up to 0.4 g/cm³) compared to those of polyethylenes obtained with the homogeneous system. The resulting polyethylenes were found to replicate the shapes of the supported borate activators. Fine polyethylene particles due to the cracking of the support were observed with the B‐Sylopol system, while well‐shaped polyethylene spheres were formed with the B‐MPS5 system.     

Subclassification of “atypia of undetermined significance” in thyroid fine‐needle aspirates

To identify the subtypes of atypia of undetermined significance (AUS) that confers a different magnitude for the risk of malignancy (RM), thyroid fine‐needle aspiration (FNA) cases carrying a diagnosis of “atypical follicular cells” or “follicular lesion” with surgical pathology followup were included in this study. The direct smears of the aspirates were rereviewed and subclassified into four subgroups based on cytomorphology: AUS cannot exclude follicular neoplasm (AUS‐FN), AUS cannot exclude Hürthle cell neoplasm (AUS‐HCN), AUS cannot exclude papillary carcinoma (AUS‐PTC) and AUS, not otherwise specified (AUS‐NOS). Based on the followup histopathologic findings, RM not including papillary microcarcinoma (PMC), RM including PMC and the risk of neoplasm (RN) were calculated for each of the four AUS subgroups. A total of 138 AUS cases were subclassified into AUS‐NOS (48), AUS‐PTC (41), AUS‐FN (32), and AUS‐HCN (17). RM not including PMC was 32% for AUS‐PTC (P < 0.001), 25% for AUS‐FN, 8% for AUS‐NOS, 0% for AUS‐HCN, and 18% for all AUS cases. RM including PMC was 54% for AUS‐PTC (P < 0.001), 34% for AUS‐FN, 19% for AUS‐NOS, 18% for AUS‐HCN, and 33% for all AUS cases. RN was 63% for AUS‐PTC (P = 0.05), 81% for AUS‐FN (P < 0.01), AUS‐HCN 53%, AUS‐NOS 44% and 59% for all cases. In our study, subclassification enabled us to further divide AUS cases into high‐ and low‐risk groups. The high‐risk group includes AUS‐PTC with a significantly higher risk of malignancy and AUS‐FN with a significantly higher risks of neoplasm. AUS‐HCN and AUS‐NOS subgroups demonstrate a lower risk of malignancy of <10%. Diagn. Cytopathol. 2014;42:23–29. © 2013 Wiley Periodicals, Inc.     

Does increase in DNA repair allow “Tolerance‐to‐Insult” in chemical carcinogenesis? Skin tumor experiments with MGMT‐overexpressing mice

Several genotoxicity endpoints have been evaluated to define nonlinear dose‐responses for S_N1 and S_N2 alkylating genotoxicants. Dose‐response studies acknowledging the process of multistage tumorigenesis are important; however, data pertaining nonlinearity are not yet available. In this communication, the role of DNA repair in the dose‐response relationship for benign papillomas was examined using the two‐stage skin carcinogenesis protocol. The data obtained with O⁶‐methylguanine‐DNA methyltransferase (MGMT) overexpressing mice in which papillomas were induced by a single topical treatment with N‐methyl‐N‐nitrosourea (MNU) followed by promotion with 12‐O‐tetradecanoylphorbol‐13‐acetate are reported. As MGMT efficiently protects cells from mutations by repairing O⁶‐methylguanine, a miscoding lesion induced by MNU, the question whether MGMT is able to nullify carcinogenic lesions to an extent where they would be considered nonhazardous has been addressed. It is shown here that MGMT overexpression significantly protects against, but does not completely nullify, the effect of MNU in tumor initiation. The possible mechanisms involved have also been discussed. Environ. Mol. Mutagen. 55:145–150, 2014. © 2013 Wiley Periodicals, Inc.     

The “Grafting‐to” of Well‐Defined Polystyrene on Graphene Oxide via Nitroxide‐Mediated Polymerization

The grafting of well‐defined polystyrene to graphene oxide (GO) using nitroxide‐mediated polymerization (NMP) is demonstrated by a two‐step reaction. In the first step, GO is functionalized with glycidyl methacrylate (GMA) to yield GO‐GMA. Polystyrene (PS), previously synthesized via SG1‐based NMP, is then grafted to GO‐GMA by a simple reaction between the SG1 end group and the GMA double bond to yield GO‐GMA‐g‐PS. ¹H, heteronuclear single‐quantum correlation (HSQC), nuclear magnetic resonance (NMR), X‐ray photoelectron spectroscopy (XPS), Raman, Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), and thermogravimetric analysis (TGA) are consistent with attachment of the GMA group to the GO surface and with polystyrene being grafted to the GO surface to form the GO‐GMA‐g‐PS nanocomposite (NC). GPC analysis shows a number‐average molecular weight of 3330 g mol^?1 for the PS with molecular weight dispersity (Ð) of 1.13. Up to 28 mass% of PS has been introduced into the GO NC. The present “grafting‐to” methodology holds promise for the facile and clean synthesis of graphene oxide polymer NCs.