bluuebunny/crossref_metadata_2025 huggingface dataset:
Oocyte–follicle cell interactions during ovarian follicle development, as seen by high resolution scanning and transmission electron microscopy in humans
Authors: Makabe Sayoko , Naguro Tomonori , Stallone Tiziana
Published: May 2006

The aim of this article is to summarize and update, through an integrated analysis by transmission electron microscopy (TEM) and high resolution scanning electron microscopy (SEM) after osmium‐dimethyl sulfoxide‐osmium (ODO) maceration, the studies of our research group on the morphodynamics of oocyte–follicle cell associations during follicle development in humans. In resting oocytes, follicular cells project few and short cytoplasmic processes in the perioocytic space. They often form bulbous terminals very close to the oolemma where zonulae adherentes, maculae adherentes, and gap junctions are present. The oolemma mostly appears smooth with short and scanty microvilli. In early growing follicles, follicular cell projections appear as (a) long and tortuous microvilli or (b) large and short extensions. The oolemma shows numerous short microvilli. By TEM, long and thin follicular “intraooplasmic processes” have been seen to penetrate deeply into some oolemma invaginations. In macerated samples, they are observed by SEM to come very close to the nucleus and contact different oocyte organelles. These processes are more likely involved in early oocyte growth. In late growing follicles, oocyte–somatic cell interactions—now established through the interposition of the zona pellucida (ZP)—preserve the general features of early growth stage, with the exceptions of “intraooplasmic processes,” which are no more present. In mature follicles subjected to a long ODO maceration, corona cells appear to contact the oocyte through an apical plume of numerous very long “curly hair‐like microvilli.” Corona cell microvilli, quite likely provide a sort of cytoplasmic skeleton for the ZP and they are possibly involved in (a) release of nutrients or removal catabolites to/from oocyte and vice versa and (b) transfer of substances to build up ZP. In conclusion, among oocyte and somatic cells a structural and functional association is revealed. This association, certainly highly dynamic in vivo, plays a key role in regulating the healthy folliculogenesis to assure a correct and timed oocyte maturation and ovulation. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Role of granulosa and theca cell interactions in ovarian follicular maturation
Authors: Tajima Kimihisa , Orisaka Makoto , Yata Hirotsugu , Goto Kenji , Hosokawa Kumiko , Kotsuji Fumikazu
Published: May 2006

We developed a culture system in which two types of ovarian follicular cells were allowed to attach to opposite sides of a collagen membrane. Using this in vitro cell culture system, we studied the effects of granulosa‐ and theca‐cell interaction on the morphology, structure, and function of bovine ovarian follicular cells. In the first part of the study, we explored how the interaction between theca and granulosa cells affects the morphology and structure of the cells. This study was done using follicular cells collected from bovine ovarian follicles at the early developmental stage. Granulosa cells cultured alone were flattened, and formed a monolayer sheet. By contrast, granulosa cells cultured with theca cells were convex, and formed multilayer sheets. Theca cells cultured alone were thin, flat, and spindle‐shaped. Theca cells cultured with granulosa cells were also spindle‐shaped; however, they appeared convex and more densely packed when compared with theca cells cultured alone. In the second part of the study, the possible role of the cellular interaction in the control of differentiation and growth of granulosa and theca cells was investigated. When follicular cells were isolated from the early stage of follicular development, theca cells reduced progesterone and inhibin production by granulosa cells and augmented the growth of granulosa cells. When the cells were isolated from the late stage of follicular development, by contrast, theca cells augmented hormonal production by granulosa cells, and did not affect the growth of granulosa cells. The growth and androstenedione production by theca cells were increased by the presence of granulosa cells, irrespective of the origin of follicular cells. These results demonstrated that communication between two types of follicular cells results in reciprocal modulation of their morphology, structure, growth, and function. Cellular interactions seem to be one of the major factors controlling the differentiation and growth of the follicular cells during the follicular maturation process. In contrast to granulosa and theca cells cultured alone, cells in the coculture seemed to possess morphological and functional characteristics more similar to those of cells in the growing follicular wall in vivo. Thus, we speculate that the interaction between these two types of follicular cells is essential for the maintenance of original structure and function of the bovine follicular wall. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Morphological patterns of angiogenesis in ovarian follicle capillary networks. A scanning electron microscopy study of corrosion cast
Authors: Macchiarelli Guido , Jiang Jin‐yi , Nottola Stefania A. , Sato Eimei
Published: May 2006

To describe the morphological characteristics of the ovarian follicle (F) capillary neoformation and regression, the angiogenic figures were studied by means of scanning electron microscopy of corrosion casts in developing and mature F of rabbit, pig, and cow. Developing F showed gradual neoformation of thecal capillaries characterized by budding and then sprouting, likely from preexisting interstitial vessels. Postcapillary venules frequently showed vasoconstriction rings (sphincters). Vasodilation followed capillary elongation. Mature F, in addition to vessel elongation and dilation, also presented infolding of dilated capillary walls, followed by capillary duplication and sinusoidalization. Periovulatory F mainly showed functional changes, such as capillary dilation, signs of iperpermeabilization, and ischemia, the latter being limited to the apical follicular area. Vessel regression was characterized by thinning of capillaries and presence of avascular areas within the atretic F wall at any stage. This study showed two main types of angiogenic patterns. (a) longitudinal elongation (in series, sprouting angiogenesis) characterizing the initial phase of F development and (b) parallel duplication (in parallel, infolding or intussusceptive angiogenesis), ending in capillary lateral replication or splitting, secondary to functional microvascular changes. Indirect evidence of the establishment of postcapillary resistances contributing to capillary remodeling, was also shown. It is concluded that the sequence of capillary neoformation in mammalian ovarian F occurs in six steps: (1) budding, (2) sprouting (and elongation), (3) dilation, (4) infolding (intussusception), (5) duplication (splitting and elongation), and (6) sinusoidalization. Capillary regression hits F at any stage and characterizes F atresia. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Structural changes and cell properties of human ovarian surface epithelium in ovarian pathophysiology
Authors: Okamura Hitoshi , Katabuchi Hidetaka , Nitta Makoto , Ohtake Hideyuki
Published: May 2006

The surface epithelial cells of the ovary, which are modified peritoneal cells, form a single, focally pseudostratified layer. The Müllerian ducts differentiate after invagination of the coelomic mesothelium over the gonadal ridges during the 6th week of embryonic life. On the basis of the embryologically putative Müllerian potential of this epithelium, endometriosis can be explained by coelomic metaplasia from the peritoneum, including ovarian surface epithelium. Some pelvic endometriosis specimens have shown that epithelial cells on the ovary or pelvis are serially changed to endometriotic gland cells. Immunohistochemistry as well as scanning electron microscopy also reinforce the light‐microscopical findings. A three‐dimensional culture system demonstrated that human ovarian surface epithelial cells exhibited a glandular–stromal structure when they were cocultured with endometrial stromal cells in an estrogen‐rich environment. Ovarian carcinomas in the epithelial–stromal category are thought to arise from the surface epithelium and its inclusions. The ovarian surface epithelium is physiologically involved in follicular rupture, oocyte release, and the subsequent repair of follicle wall during reproductive age. Simultaneously, ovulation may cause a loss of integrity of the surface epithelium, followed by accumulation of multiple mutations. The cortical invagination, surface stromal proliferation, and Müllerian differentiation of these cells are likely not to be an early step in the cancer development. However, the inclusion cysts are closely related with carcinogenesis because they are significantly more common in ovaries contralateral to those containing epithelial cancers than in control ovaries. As an in vitro study, ovarian carcinoma cell lines were established from simian virus 40 large T antigen‐transformed human surface epithelial cells of the ovary. Further investigations of these cell lines may lead to insights into the preneoplastic and early stages of carcinomas. To clarify the pathogenesis of endometriosis and epithelial ovarian cancer, specifically designed studies of ovarian surface epithelium are required. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Ultrastructural characteristics of human granulosa cells in a coculture system for in vitro fertilization
Authors: Nottola Stefania A. , Heyn Rosemarie , Camboni Alessandra , Correr Silvia , Macchiarelli Guido
Published: May 2006

The use of somatic cells for cocultures during in vitro fertilization (IVF) is currently finalized to obtain a higher number of healthy and viable embryos with a high potential of implantation. Among the different cell lines that can be used as feeder cells for cocultures, granulosa cells (GCs) are autologous cells, safe and easy to recover. The aim of the present study was to analyze the fine structure of human GCs used in a coculture system to evaluate, from a morphodynamic point of view, their role in supporting embryo development. GCs were collected during oocyte pick‐up, 36 h after human chorionic gonadotropin administration, from patients undergoing IVF procedures, who had given their informed consent to be included in this protocol. After coculture, GCs were fixed and processed for light microscopy (LM) and transmission electron microscopy (TEM). By LM, GCs appeared as clusters of loosely packed cells, irregularly rounded or polyhedral in shape, varying in diameter from 18 to 25 μm. Mitotic cells, as well as regressing elements (with pyknotic nuclei or dense cytoplasm) and cell fragments were occasionally observed. By TEM, the plasma membrane was irregular due to the presence of cytoplasmic evaginations. Linear and annular gap junctions between neighboring GCs were found. GC nuclei, rounded and eccentrically located, contained finely dispersed chromatin, one (often two) prominent nucleoli and, infrequently, peripheral patches of heterochromatin. Numerous organelles populated the GC cytoplasm, among them, mitochondria were rod‐shaped or elongated, usually provided with tubular–vesicular cristae but occasionally showing atypical, longitudinally oriented cristae. Membranes of smooth endoplasmic reticulum, Golgi stacks and vesicles, secretory‐like granules, cisternae of rough endoplasmic reticulum (RER), free ribosomes and polysomes, lysosomal‐like bodies, microfilaments, and lipid droplets were also seen in the GC cytoplasm. In most cells, RER was scarcely represented and numerous lipid droplets filled the perinuclear space. On the contrary, some GCs contained an abundant RER and rare lipid droplets scattered in the cytoplasm. In conclusion, our data demonstrated the presence, in a coculture system, of GCs provided with ultrastructural characteristics typical of healthy, metabolically active, mostly steroidogenic cells. Protein‐synthetic cells have also been detected. These data, evaluated at the light of biochemical and clinical studies, sustain the capability of human GCs cocultures to positively affect early embryo development in vitro by the secretion of steroids and proteins, putative “embryotrophic” factors. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Histological changes in rat nasal epithelia after unilateral neonatal naris occlusion
Authors: Cámara José A. , Garrosa Manuel , Gayoso Manuel J.
Published: May 2006

The authors studied the extent of the different epithelia lining the nasal fossae of the albino rat after neonatal closure of one naris. Newborn pups were anesthetized by hypothermia and the external opening of their right naris cauterized, while littermates served as controls. Animals were sacrificed at 3 months, and the occluded (OCF) and nonoccluded (NOF) fossae of experimental animals as well as both fossae of control animals (CTF) were histologically studied. In both control and experimental animals, nasal fossae were lined by five different types of epithelia: squamous stratified, transitional, metaplastic, respiratory, and olfactory epithelia. It was found that closure of one naris provokes reorganization of the epithelial lining in both the occluded and nonoccluded side. In CTF airflow, physical conditions as well as pollutants and biological agents irritate the epithelial lining, causing squamous metaplasia as well as metaplastic epithelium showing inflammation in rostral levels. In CTF caudal levels, the metaplastic epithelium appears to a lesser degree and the respiratory epithelium prevails, except for the most caudal level where the olfactory epithelium is prevalent. In OCF, the protected environment created prevents the occurrence of metaplastic epithelium, the transitional, respiratory, and olfactory epithelia developing in the corresponding area instead. In NOF, where the airflow is double, the same pattern occurs as in CTF, although metaplastic epithelium values are approximately double, suggesting a clear linear effect. An outstanding feature observed was the increased extent of the olfactory epithelium in OCF regarding NOF, although changes in its morphological structure were not found. Airflow properties, including pressure, coldness, velocity, and turbulence, as well as biological and chemical hazards present in inflow, cause histological reorganization of the nasal epithelium lining during postnatal development. Results prove the need to consider airflow changes in nasal fossae surgery and point to the protective value of naris closure in ENT clinics, supporting it as a treatment of atrophic rhinitis. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Electronic structure analyses of BN network materials using high energy‐resolution spectroscopy methods based on transmission electron microscopy
Authors: Terauchi M.
Published: May 2006

Electronic structures of boron‐nitride (BN) nanotubes and a BN cone‐structure material were studied by using a high energy‐resolution electron energy‐loss spectroscopy (EELS) microscope. A trial of the whole electronic structure study of hexagonal BN (h‐BN), which consists of flat BN honeycomb layers, was conducted by a combination of EELS and X‐ray emission spectroscopy (XES) based on transmission electron microscopy (TEM) (TEM‐EELS/XES). The π and π+σ plasmon energies of BN nanotubes (BNT) were smaller than those of h‐BN. The π+σ energy was explained by the surface plasmon excitation. The spectrum of a two‐wall BNT of 2.7 nm in diameter showed a new spectral onset at 4 eV. The valence electron excitation spectra obtained from the tip region of the BN cone with an apex angle of 20° showed similar intensity distribution with those of BNTs. The B K‐shell electron excitation spectra obtained from the bottom edge region of the BN cone showed additional peak intensity when compared with those of h‐BN and BNT. The B K‐shell electron excitation spectra and B K‐emission spectra of h‐BN were compared with a result of a LDA band calculation. It showed that high symmetry points in the band diagram appear as peak and/or shoulder structures in the EELS and XES spectra. Interband transitions appeared in the imaginary part of the dielectric function of h‐BN experimentally obtained were assigned in the band diagram. The analysis also presented that the LDA calculation estimated the bandgap energy smaller than the real material by an amount of 2 eV. Those results of TEM‐EELS/XES analysis presented that high energy‐resolution spectroscopy methods combined with TEM is a promising method to analyze whole electronic structures of nanometer scale materials. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Determination of the propylene oxide–hemoglobin adduct by gas chromatography‐electron impact ionization mass spectrometry
Authors: Shin Ho‐Sang , Ahn Hye‐Sil
Published: May 2006

A gas chromatography‐mass spectrometry method was developed for the determination of the propylene oxide (PO)–hemoglobin adduct. The adduct was identified as hydroxy propyl valine (HPV), and released from globin by the modified Edman degradation and extracted with ethyl ether. HPV and deuterated HPV (d6‐HPV) were synthesized for identification and quality control. d6‐HPV was used as an internal reference standard. The dried extract was completely derivatized with N‐methyl‐N‐(trimethylsilyl) trifluoroacetamide (MSTFA). The method detection limit (MDL) of the assay was 10 pmole/g for HPV, based on assayed hemoglobin of 0.1 g. The method was applied to the determination of the PO–hemoglobin adduct formed in young female Sprague–Dawley rats after treatment for 4 and 5 weeks with 5 and 10 mM PO via drinking water. HPV was detected by the proposed procedure. After 4 weeks, the concentration of HPV was 6.75 nmole/g hemoglobin during treatment with 5 mM, and 80.26 nmole/g hemoglobin during treatment with 10 mM. The adduct level in 5 weeks increased up to about 51.47 nmole/g during treatment with 5 mM PO in the drinking water and up to about 120.27 nmole/g during treatment with 10 mM PO. This method was also applied to determine the concentrations of HPV in the blood of 20 persons living near the Ulsan petroleum industrial complex in Korea. As a result, HPV‐hemoglobin adduct was detected in the concentration range 0–1100 pmol/g in the human blood samples. Copyright © 2006 John Wiley & Sons, Ltd.
Determination of polycyclic aromatic hydrocarbons in olive oil by a completely automated headspace technique coupled to gas chromatography‐mass spectrometry
Authors: Arrebola Francisco J. , Frenich A. Garrido , González Rodríguez Manuel J. , Bolaños Patricia Plaza , Martínez Vidal José L.
Published: May 2006

A new and completely automated method for the determination of ten relevant polycyclic aromatic hydrocarbons (PAHs) in olive oil is proposed using an extraction by the headspace (HS) technique. Quantification and confirmation steps are carried out by gas chromatography‐mass spectrometry (GC‐MS) combining simultaneously selected‐ion monitoring (SIM) and tandem mass spectrometry (MS/MS). This combination offers on one hand an increased sensitivity and on the other hand, selective and reliable qualitative information. Sample pretreatment or clean‐up are not necessary because the olive oil sample is put directly into an HS vial, automatically processed by HS and introduced into the GC‐MS instrument for analysis. Because of its high selectivity and sensitivity, a triple‐quadrupole (QqQ) detector coupled with the gas chromatograph allows us to limit handling. Each sample is completely processed in approximately 63 min (45 min for HS isolation and 18 min for GC‐MS determination), a reduced time compared with previously published methods. The chemical and instrumental variables were preliminarily optimized using uncontaminated olive oil samples spiked with 25 µg kg−1 of each target compound. The final method was validated to ensure the quality of the results. The precision was satisfactory, with relative standard deviation (RSD) values in the range 3–9%. Recovery rates ranged from 96 to 99%. Limits of detection (LOD) were calculated as 0.02–0.06 µg kg−1 and the limits of quantification (LOQ) were obtained as 0.07–0.26 µg kg−1. It must be mentioned that the LOD and LOQ are much lower than the maximum levels established by the European Union (EU) in oils and fats intended for direct human consumption or for use as an ingredient in foods, which are set at 2 µg kg−1. All the figures of merit are completely in accordance with the latest EU legislation. This fact makes it possible to consider the proposed method as a useful tool for the control of PAHs in olive oils. Copyright © 2006 John Wiley & Sons, Ltd.
Combining ability and heritability for vitamin C and total soluble solids in pepper (Capsicum annuum L.)
Authors: Geleta Legesse F , Labuschagne Maryke T
Published: May 2006

Twenty‐one F1 hybrids and seven parental genotypes were used to assess combining ability and heritability for vitamin C and total soluble solids in pepper (Capsicum annuum L.). The mean squares for general (GCA) and specific (SCA) combining abilities were highly significant for the two traits, suggesting the importance of both additive and non‐additive gene effects. However, additive gene action was more important, as GCA estimates were much higher than SCA effects. Among the parental genotypes, ‘Mareko Shote’ and ‘PBC 142A’, and ‘PBC 142A’ were good general combiners for vitamin C and total soluble solids, respectively, and could be used to improve these traits in pepper breeding programmes for the accumulation of favourable genes. They also showed the highest per se performance (315.3 mg 100 g−1 and 18.5 Brix, respectively) for the two quality traits. The narrow sense heritability estimate for vitamin C was relatively high (54.8%) indicating that the environment had a less pronounced effect on this trait. The heritability for total soluble solids was low (15%). Copyright © 2006 Society of Chemical Industry
Occurrence of acetic acid and formic acid in breakfast cereals
Authors: Rufián‐Henares José A , Delgado‐Andrade Cristina , Morales Francisco J
Published: May 2006

Breakfast cereals are usually manufactured by extrusion followed by drying and toasting steps in which thermal treatments are applied. In addition, owing to the low water activity and the content in cereals of proteins and carbohydrates, precursors of the Maillard reaction, this reaction and degradation of sugars are favoured during processing. Acetic and formic acids have been identified as final products of Maillard reaction (MR) and sugar caramelisation. Acetic and formic acid contents have been determined by ion exchange high‐performance liquid chromatography in 56 commercial breakfast cereals. Results were evaluated taking into account the sample formulation. Acetic and formic acids were detected in all samples, and significant variations were observed for acetic acid depending on the protein and fibre content. Acetic acid, originating from 1‐deoxyglucosone cleavage during MR, proved to be a good indicator of processing in cereals enriched with or based on wheat flour because of their high protein content. Fibre addition increased acetic acid concentration. The application of acetic acid as a chemical marker of processing in breakfast cereals and its possible generation pathways are discussed. Copyright © 2006 Society of Chemical Industry
Inactivation kinetics of pectin methylesterase in orange juice as a function of pH and temperature/time process conditions
Authors: Tribess Tatiana B , Tadini Carmen C
Published: May 2006

Pasteurisation of orange juice (OJ) is necessary to prevent spoilage due to microorganisms and enzymes, mainly pectin methylesterase (PME). PME has a higher thermal resistance than the bacteria and yeasts existing in OJ and therefore its inactivation is used as a parameter to define the time/temperature combination of the thermal process. The enzyme has isoforms with different activities and thermal resistances. A three‐parameter model can be used to describe the kinetics of PME inactivation, where the more and less thermally resistant fractions are represented. In this study the thermal inactivation kinetics was evaluated at six pH values (3.6, 3.7, 3.8, 3.9, 4.0 and 4.1), three minimal temperatures (82.5, 85.0 and 87.5 °C) and at least six holding times for each condition. It was found that the thermolabile PME fraction (a) was influenced by pH and processing temperature. A slower reaction rate constant (k1) was found for juices with pH values of 3.8 and 3.9 at the studied temperatures. The highest inactivation levels were obtained in juices with pH values of 3.6 and 3.7. Copyright © 2006 Society of Chemical Industry
Effect of garlic powder on the performance, egg traits and blood parameters of laying hens
Authors: Yalçın Sakine , Onbaşılar E Ebru , Reisli Zehra , Yalçın Suzan
Published: May 2006

This study was conducted to investigate the effects of garlic powder on the performance, egg traits and blood parameters of laying hens. One hundred and sixty‐two SHSY‐type brown layers aged 21 weeks were chosen at random from a large flock. They were allocated to three dietary treatments. Each treatment comprised six replicates of nine layers in groups of three. The diets were supplemented with 0, 5 and 10 g kg−1 garlic powder. The experimental period lasted 22 weeks. Garlic powder addition did not significantly affect body weight, egg production, feed consumption, feed efficiency, egg shell index, egg breaking strength, egg shell thickness, egg albumen index, egg yolk index, egg Haugh unit, egg yolk weight and serum protein concentration. Egg weight increased (P < 0.01) with garlic powder supplementation. There was a significant (P < 0.01) reduction in egg cholesterol concentration as mg g−1 yolk when the dietary level of garlic powder was increased from 0 to 10 g kg−1. Hen serum triglyceride (P < 0.05) and total cholesterol (P < 0.01) concentrations decreased with garlic powder supplementation. This study demonstrated that garlic powder addition increased egg weight and decreased egg yolk cholesterol concentration (mg g−1 yolk) and serum triglyceride and cholesterol concentrations without adverse effects on performance and egg traits. Copyright © 2006 Society of Chemical Industry
A systematic approach for extraction of phenolic compounds using parsley (Petroselinum crispum) flakes as a model substrate
Authors: Luthria Devanand L , Mukhopadhyay Sudarsan , Kwansa Albert L
Published: May 2006

The impact of extraction methodology and polarity of extraction solvents on the assay of phenolic compounds was investigated using parsley (Petroselinum crispum) flakes as a model substrate. This systematic study was undertaken to address substantial variations in the extraction procedures, solvents and conditions as described in the recent literature. Five different extraction procedures [shaking, vortex mixing, sonication, stirring and pressurized liquid extraction (PLE)] and three different solvents (methanol, ethanol and acetone), with five different solvent to water ratios per solvent, were used for extraction. Extracts were analyzed for phenolic content by high‐performance liquid chromatography and Folin–Ciocalteu assays. The yields of phenolic compounds extracted with a pressurized liquid extractor were comparable to or better than those of four classical extraction procedures. Optimum extraction efficiency with PLE was obtained when extractions were performed with four extraction cycles using ethanol–water (50:50, v/v). The amount of apiin (4,5,7‐trihydroxyflavone 7‐apiosylglucoside) and malonylapiin (apigenin malonylapiosylglucoside) isolated from parsley varied with the composition of extraction solvent. Apiin extractability was found to be a maximum when the solvent (ethanol, methanol or acetone) to water ratio was 30:70 (v/v), whereas higher amounts of malonylapiin were isolated with a reverse solvent to water ratio (70:30, v/v). Malonylapiin was not detected when parsley samples were extracted with organic solvent to water ratios of 10:90 (v/v) and 30:70 (v/v). Published in 2006 by John Wiley & Sons, Ltd
Synthesis of Substituted Polyacetylenes Grafted with Polystyrene Chains by the Macromonomer Method and Their Characterization
Authors: Zhang Wei , Shiotsuki Masashi , Masuda Toshio
Published: May 2006

Summary: A macromonomer (1) consisting of a polystyrene chain and an acetylenic chain end ($\overline M _{\rm n}$ = 2 500, $\overline M _{\rm w} /\overline M _{\rm n}$ = 1.20) was prepared by atom transfer radical polymerization. Macromonomer 1 was copolymerized with phenylacetylene (2) and propargyl 2‐bromopropionate (3) by using Rh catalysts at varying feed ratios from 10 to 50 wt.‐% to produce graft copolymers 4 and 5, respectively. The synthesized copolymers 4 and 5 possessed a conjugated polyene main‐chain and polystyrene grafts, and contained 11–34 and 16–77 wt.‐% of polystyrene with $\overline M _{\rm n}$ of 61 400–144 000 and 19 300–22 500, respectively. Graft copolymer 4 was a yellow solid and thermally stable up to 225 °C, whereas 5 was a brown solid with weight loss beginning at 175 °C. Graft copolymers 4 and 5 exhibited UV‐vis absorption edges at 525 and 425 nm, respectively, which are attributable to the conjugated main‐chain structure.

Copolymerization of the acetylene‐terminated polystyrene‐based macromonomer with monosubstituted acetylenes.

magnified image

Copolymerization of the acetylene‐terminated polystyrene‐based macromonomer with monosubstituted acetylenes.
Quantitative Analysis of Dielectric Constants from EFM Images of Multicomponent Polymer Blends
Authors: Krayev Andrey V. , Shandryuk Georgy A. , Grigorov Leonid N. , Talroze Raisa V.
Published: May 2006

Summary: A simple quantitative model for the analysis of EFM images of three‐ or more‐component polymer blends is applied to determine the dielectric constants of the blend constituents. The value of the dielectric constant of PIPA calculated from the EFM images of POMA‐PIPA‐APP blend is determined in good agreement with the literature value.

magnified image
RAFT Polymerization of N‐Isopropylacrylamide and Acrylic Acid under γ‐Irradiation in Aqueous Media
Authors: Millard Pierre‐Eric , Barner Leonie , Stenzel Martina H. , Davis Thomas P. , Barner‐Kowollik Christopher , Müller Axel H. E.
Published: May 2006

Summary: The ambient temperature (20 °C) reversible addition fragmentation chain transfer (RAFT) polymerization of N‐isopropylacrylamide (NIPAAm) and acrylic acid (AA) conducted directly in aqueous media under γ‐initiation (at dose rates of 30 Gy · h−1) proceeds in a controlled fashion (typically, $\overline M _{\rm w} /\overline M _{\rm n}$ < 1.2) to near quantitative conversions and up to number‐average molecular weights of 2.5 × 105 g · mol−1 for PNIPAAm and 1.1 × 105 g · mol−1 for PAA via two water‐soluble trithiocarbonate chain transfer agents, i.e., S,S‐bis(α,α′‐dimethyl‐α″‐acetic acid)trithiocarbonate (TRITT) and 3‐benzylsulfanylthiocarbonylsulfanyl propionic acid (BPATT). The generated polymers are successfully chain extended, which suggests that the RAFT agents are stable throughout the polymerization process so that complex and well‐defined architectures can be obtained.

An increase of the monomer/CTA ratio leads to an increase of the molecular weight for the RAFT polymerization of NIPAAm under γ‐radiation in water using TRITT at ambient temperature.

image

An increase of the monomer/CTA ratio leads to an increase of the molecular weight for the RAFT polymerization of NIPAAm under γ‐radiation in water using TRITT at ambient temperature.
First Successful Post‐Synthetic Self‐Assembly of Polyaniline with Poly(N‐vinylpyrrolidone) into Aqueous Nanocolloids
Authors: Li Guorong , Li Bogeng
Published: May 2006

Summary: Polyaniline (PANI) is successfully self‐assembled with poly(N‐vinylpyrrolidone) (PVP) into aqueous nanocolloids. The typical morphology of the colloids is studied by atomic force microscopy (AFM), which reveals spherical nanoparticles with a diameter of 80–150 nm. A possible mechanism for such a post‐synthetic self‐assembly process is proposed.

AFM micrograph of PANI aqueous nanocolloids stabilized by PVP via a novel post‐synthetic self‐assembly method.

image

AFM micrograph of PANI aqueous nanocolloids stabilized by PVP via a novel post‐synthetic self‐assembly method.
Amplification and diversity analysis of ketosynthase domains of putative polyketide synthase genes in Aspergillus ochraceus and Aspergillus carbonarius producers of ochratoxin A
Authors: Atoui Ali , Phong Dao Huy , Mathieu Florence , Lebrihi Ahmed
Published: May 2006

The diversity of polyketide synthase (PKS) genes in Aspergillus ochraceus NRRL 3174 and Aspergillus carbonarius 2Mu134 has been investigated using different primer pairs previously developed for the ketosynthase (KS) domain of fungal PKSs. Nine different KS domain sequences in A. ochraceus NRRL 3174 as well as five different KS domain sequences in A. carbonarius 2Mu134 have been identified. The identified KS fragments were distributed in five different clusters on the phylogenetic tree, indicating that they most probably represent PKSs responsible for different functions.
Sampling: the weak link in the sanitary quality control system of agricultural products
Authors: Blanc Michel
Published: May 2006

To ensure a high level of consumer protection, the European Union has in the past years published several regulations setting very low limits for a given number of food contaminants (pesticides, mycotoxins, heavy metals) in many agricultural products (cereals, oilseeds, dry fruits, coffee, spices, etc). These new regulations regarding the sanitary quality of agricultural products, compel both economic operators and officials of different EU member states to set up sampling plans and rigorous analyses aimed at checking whether a product lot complies with the required standards prior to its release on the market. While the laboratory analysis management today is outstanding thanks to the validated and efficient detection methods and procedures available for quality assurance in laboratories (accreditation), this is not necessarily true of the sampling operation, which seems to be the weak link in the sanitary control system for agricultural products. The sampling operation is often the main source of error when assessing the sanitary quality of a lot of agricultural commodities, with both commercial (downgrading of the product) and sanitary (marketing of a product which poses a health risk for the consumer) consequences. Therefore, it is essential for the operators involved to be aware of the significance and difficulties of the sampling operation, which requires important equipment and human resources. Furthermore, drawing up specific standards and guidelines, as well as setting up quality assurance procedures, at the level in charge of carrying out this delicate and important operation, are necessary.
Detection of small‐fiber neuropathy by sudomotor testing
Authors: Low Victoria A. , Sandroni Paola , Fealey Robert D. , Low Phillip A.
Published: May 2006

The symptoms of burning sensation affecting the feet, thought to be due to a distal small‐fiber neuropathy (DSFN) affecting somatic unmyelinated fibers, are usually accompanied by vasomotor or sudomotor changes suggestive of involvement of autonomic fibers. We therefore examined the relationship between pattern of anhidrosis and DSFN and its etiology, comparing patients with “pure” DSFN (with normal nerve conduction) to those with clinical DSFN (minor conduction abnormalities). We reviewed 125 cases with a clinical phenotype of DSFN. These patients had distal burning discomfort, variable sensory deficits, and intact motor function. All had undergone assessment with thermoregulatory sweat test (TST), autonomic reflex screen (ARS), and nerve conduction studies and electromyography (NCS/EMG). TST showed a distal pattern of anhidrosis in 74%. The quantitative sudomotor axon reflex test (QSART) was abnormal in 74%, with 80% of those having a length‐dependent pattern of anhidrosis/hypohidrosis. In total, 93% of patients had a distal pattern of abnormality on QSART or TST. The Composite Autonomic Severity Score (CASS) was used to quantify the severity and distribution of autonomic deficits: 98% had CASS abnormality (sudomotor, 98%; adrenergic, 43%; cardiovagal, 35%). EMG was normal or showed unrelated abnormalities in 75%. The most common etiologies of DSFN were idiopathic (73%), presumed hereditary (18%), and diabetes (10%). Sudomotor examination is thus a highly sensitive detection tool in DSFN. Autonomic involvement is mainly distal, and additionally may involve adrenergic and the long cardiovagal fibers. Muscle Nerve, 2006
Alterations in the gastrocnemius muscle of undernourished suckling rats
Authors: Silvado Carlos Eduardo , Werneck Lineu Cesar
Published: May 2006

Protein‐energy undernutrition (PEU) during both the gestational and suckling periods causes a reduction in muscle fiber cross‐section and a delay in fiber type differentiation. Such changes are not found when PEU occurs after the suckling period. To elucidate the consequences of PEU on muscle during the suckling period, we undernourished (UND) newborn rats by reducing their food intake, including a 6‐hour fast every day, and doubling the number of pups suckled by the nursing rat. At day 24 of life, the gastrocnemius muscle showed a discrete reduction in lipids in the fibers of 5 control rats, and in 15 UND rats (P < 0.001). The type 2a and 2b fibers of the UND rats showed a smaller cross‐sectional area than control rats (P < 0.05). The distribution frequency histogram for the muscle fibers was skewed to the left in the undernourished rats, and this was significant for type 2a and 2b fibers. PEU during the suckling period may thus induce a delay in muscle fiber maturation but does not produce significant structural alterations. Muscle Nerve, 2006
Prenatal diagnosis of free sialic acid storage disorders (SASD)
Authors: Aula Nina , Aula Pertti
Published: May 2006

Free sialic acid storage disorders, Salla disease (SD) and Infantile sialic acid storage disease (ISSD), are lysosomal storage diseases due to impaired function of a sialic acid transporter, sialin, at the lysosomal membrane. Several mutations of the sialin gene, SLC17A5, are known, leading either to the severe neonatal/infantile disease or to the milder, adult‐type developmental disorder, Salla disease. Free sialic acid accumulation in lysosomes causes increased tissue concentration and consequently elevated urinary excretion. Prenatal diagnosis of SASD is possible either by determination of free sialic acid concentration or by mutation analysis of the SLC17A5 gene in fetal specimen, in chorionic villus biopsy particularly. Both techniques have been successfully applied in several cases, sialic acid assay more often in ISSD cases but mutation analysis preferentially in SD. Sialic acid assay of amniotic fluid supernatant or cultured amniotic fluid cells may give erroneous results and should not be used for prenatal diagnosis of these disorders. The present comments are mainly based on our experience of prenatal diagnosis of SD in Finnish families. A founder mutation in SLC17A5 gene, 115C‐> T, represents 95% of the disease alleles in the Finnish SD patients, which provides a unique possibility to apply mutation analysis. Therefore, molecular studies have successfully been used in 17 families since the identification of the gene and the characterization of the SD mutations. Earlier, eight prenatal studies were performed by measuring the free sialic acid concentration in chorionic villus samples. Copyright © 2006 John Wiley & Sons, Ltd.
Prenatal diagnostic indicators of paternal uniparental disomy 14
Authors: Curtis Logos , Antonelli Eric , Vial Yvan , Rimensberger Peter , Le Merrer Martine , Hinard Christine , Bottani Armand , Fokstuen Siv
Published: May 2006

Objectives

To present clinical findings of a child with paternal uniparental isodisomy 14 (pat UPD14) focusing on relevant prenatal characteristics.

Methods/Results

Ultrasonography at 23 weeks of gestation of a 37‐year‐old multigravid woman revealed a fetus with polyhydramnios, small thorax, and short, distinctively angled ribs. Fetal karyotype was 46,XY. The child was born spontaneously at 35 weeks with poor neonatal adaptation. From birth, he presented with severe respiratory insufficiency due to severe thoracic malformation. Clinical examination revealed a small, bell‐shaped thorax, redundant lax skin, mild contractures of the fingers and dysmorphic facial features. Chest X rays showed short, abnormally curved ribs that suggested the possibility of pat UPD14, which was confirmed by molecular analysis.

Conclusion

Pat UPD14 is associated with a distinct clinical phenotype. Prognosis is poor because of severe respiratory insufficiency and neurodevelopmental retardation. Our report confirms salient postnatal signs of previous descriptions, especially the characteristic radiological abnormalities with ribs showing a ‘coat‐hanger’ configuration. Retrospective fetal ultrasound of our case allowed the identification of this pathognomonic feature prenatally, which makes it possible to consider pat UPD14 at routine prenatal sonography, in particular in combination with a small bell‐shaped thorax and polyhydramnios. Copyright © 2006 John Wiley & Sons, Ltd.
Prenatal diagnosis of Freeman–Sheldon syndrome and usefulness of an ultrasound fetal lip width normogram
Authors: Vimercati Antonella , Scioscia Marco , Burattini Maria Gabriella , Pontrelli Giovanni , Selvaggi Luigi E.
Published: May 2006

Objectives

Freeman–Sheldon syndrome (FSS) is a rare genetic condition with facial and joint abnormalities. Here we report the first case of prenatal diagnosis in a fetus with negative familial history for this syndrome. A chart of the fetal mouth length was generated and its usefulness verified.

Methods

A cross‐sectional study was carried out to derive standard charts for fetal lip lengths. The study population was made up of 371 fetuses between 15 and 38 weeks of gestation examined only once for this purpose. A statistical analysis previously recommended to derive normal ranges in fetal growth charts was employed.

Results

A 34‐year‐old woman was referred at 28 weeks of gestation for polyhydramnios and clubfeet. A detailed scan confirmed those findings and showed joint contractures of hands, a severe microstomia with a ‘whistling’ mouth, and an H‐shaped mark over the chin. FSS was suspected, though there was no family history for this genetic syndrome. After emergency delivery at 32 weeks, the syndrome was confirmed. The infant died two months later from pneumonia. Upon construction of a standard mouth length chart, it was found that the fetal lip width in this case of FSS was well below the 5th centile.

Conclusion

Here we present a standard chart for fetal lip width. We demonstrated its usefulness in cases with fetal face anomalies. Specific charts are fundamental for an objective assessment of the fetal parameters. Copyright © 2006 John Wiley & Sons, Ltd.
Antidepressant prevalence for youths: a multi‐national comparison
Authors: Zito Julie M. , Tobi Hilde , de Jong‐van den Berg Lolkje T.W. , Fegert Joerg M. , Safer Daniel J. , Janhsen Katrin , Hansen Dorte Gilså , Gardner James F. , Glaeske Gerd
Published: May 2006

Objective

To compare antidepressant prevalence data in youths across three western European countries (Denmark, Germany, and the Netherlands) with US regional data in terms of age and gender and to show proportional subclass antidepressant (ATD) use.

Method

A population‐based analysis of administrative claims data for the year 2000 was undertaken in 0 to 19‐year‐old enrollees who were part of the insured populations from four countries having a total of from 72,570 to 480,680 members.

Results

ATD medication utilization in the US dataset (1.63%) exceeded that of three Western European countries (prevalence ranged from 0.11 to 0.54%) by at least 3‐fold. There were major variations in the use of subclasses: tricyclic antidepressants (TCAs) predominated in Germany while selective serotonin reuptake inhibitors (SSRIs) predominated in the US, Denmark and the Netherlands.

Conclusions

Cross‐national variations should be further explored to understand the factors related to these differences and how prevalence differences relate to effectiveness and safety. Community‐based cohorts should be followed to establish outcomes in the usual practice setting. Copyright © 2006 John Wiley & Sons, Ltd.
Adapting the sample size planning of a phase III trial based on phase II data
Authors: Wang Sue‐Jane , Hung H. M. James , O'Neill Robert T.
Published: May 2006

Traditionally, in clinical development plan, phase II trials are relatively small and can be expected to result in a large degree of uncertainty in the estimates based on which Phase III trials are planned. Phase II trials are also to explore appropriate primary efficacy endpoint(s) or patient populations. When the biology of the disease and pathogenesis of disease progression are well understood, the phase II and phase III studies may be performed in the same patient population with the same primary endpoint, e.g. efficacy measured by HbA1c in non‐insulin dependent diabetes mellitus trials with treatment duration of at least three months. In the disease areas that molecular pathways are not well established or the clinical outcome endpoint may not be observed in a short‐term study, e.g. mortality in cancer or AIDS trials, the treatment effect may be postulated through use of intermediate surrogate endpoint in phase II trials. However, in many cases, we generally explore the appropriate clinical endpoint in the phase II trials. An important question is how much of the effect observed in the surrogate endpoint in the phase II study can be translated into the clinical effect in the phase III trial. Another question is how much of the uncertainty remains in phase III trials. In this work, we study the utility of adaptation by design (not by statistical test) in the sense of adapting the phase II information for planning the phase III trials. That is, we investigate the impact of using various phase II effect size estimates on the sample size planning for phase III trials. In general, if the point estimate of the phase II trial is used for planning, it is advisable to size the phase III trial by choosing a smaller alpha level or a higher power level. The adaptation via using the lower limit of the one standard deviation confidence interval from the phase II trial appears to be a reasonable choice since it balances well between the empirical power of the launched trials and the proportion of trials not launched if a threshold lower than the true effect size of phase III trial can be chosen for determining whether the phase III trial is to be launched. Published in 2006 by John Wiley & Sons, Ltd.