bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tropical alluvial forest fragmentation in the eastern lowlands of Colombia (1939–1997)
Authors: Madriñán L. F. , Etter A. , Boxall G. D. , Ortega‐Rubio A. 
Published: August 2006

AbstractAlluvial forests are under high pressure from human activities because of their value as agricultural, wildlife, timber and recreational land. Despite this, spatial patterns of alluvial forest deforestation are not well known. We studied forest alterations in a 2800 ha alluvial ecosystem using aerial photographs. During the study period (1939–1997), forests with canopy heights greater than 15 m (high canopy mature forest; HCM forest) decreased by 70·4 per cent while forests with canopy heights less than 15 m (low canopy mature forest; LCM forest) forests decreased by 51 per cent, producing a highly fragmented landscape. Factors responsible for forest change included human activities and river dynamics. Although most of the deforestation was related to human disturbance, almost 27 per cent of forest losses were due to channel migration of the Meta River. HCM forests were the most affected land cover since they are easily accessed, viable for logging and occurred on fertile soils, which are valuable for agriculture. LCM forests were less affected since their soil fertilities and inundation regimes were unfavourable to human uses, and thus, less prone to anthropogenic disturbances. Copyright © 2006 John Wiley & Sons, Ltd.
Changing grazing systems in central north Namibia
Authors: Verlinden A. , Kruger A. S. 
Published: August 2006

AbstractCurrent and historical livestock movement patterns are explored in a semi‐arid communal environment in central–north Namibia, placed in context of increasing population, large‐scale enclosures, increased water supply and changing vegetation. Farmer's knowledge of movements, rangeland potential, vegetation condition and plant indicators was gathered and analysed with various methods such as Canonical Correspondence Analysis (CCA). Local rangeland units were mapped with Landsat TM imagery and analysed with a Geographical Information System (GIS). The data suggest that good grazing was previously maintained by low herbivore pressure and frequent fires in a management regime controlled by hunter‐gatherers and limited permanent water supply.Population increase in settled areas starts migration to more fertile land units in previous prime grazing areas causing a conflict between grazing and cropping and a decrease in grazing condition triggering further migration and need for new water supply. Recent large‐scale enclosures are targeting predominantly more fertile land units with the most palatable perennial grass species and water, causing further conflict for communal farmers.Having reached the frontier of the traditional land there is no space for further expansion, resulting in the need to adapt to uncertainty with annual grasses more dependent on rainfall. Livestock movement patterns have changed drastically for large herd owners from transhumance and migration to largely permanent cattle posts. Small herd owners face increasing longer movements between kraals, water points, depending on less suitable and decreased unfenced grazing lands. Copyright © 2006 John Wiley & Sons, Ltd.
Low‐level laser irradiation modulates matrix metalloproteinase activity and gene expression in porcine aortic smooth muscle cells
Authors: Gavish Lilach , Perez Louise , Gertz S. David 
Published: August 2006

AbstractBackground and ObjectivesThe vascular extracellular matrix is maintained by a dynamic balance between matrix synthesis and degradation. This equilibrium is disrupted in arterial pathologies such as abdominal aortic aneurysm. Low‐level laser irradiation (LLLI) promotes wound healing. However, its effect on smooth muscle cells (SMCs), a central player in these responses, has not been established. The current study was designed to determine the effects of LLLI on arterial SMC proliferation, inflammatory markers, and matrix proteins.Study Design/Materials and MethodsPorcine primary aortic SMCs were irradiated with a 780 nm laser diode (1 and 2 J/cm2). Trypan blue exclusion assay, immunofluorescent staining for collagen I and III, Sircol assay, gelatin zymography, and RT‐PCR were used to monitor proliferation; collagen trihelix formation; collagen synthesis; matrix metalloproteinase‐2 (MMP‐2) activity, and gene expression of MMP‐1, MMP‐2, tissue inhibitor of MMP‐1 (TIMP‐1), TIMP‐2, and IL‐1‐β, respectively.ResultsLLLI‐increased SMC proliferation by 16 and 22% (1 and 2 J/cm2, respectively) compared to non‐irradiated cells (P<0.01 and P<0.0005). Immediately after LLLI, trihelices of collagen I and III appeared as perinuclear fluorescent rings. Collagen synthesis was increased twofold (2 days after LLLI: 14.3±3.5 µg, non‐irradiated control: 6.6±0.7 µg, and TGF‐β stimulated control: 7.1±1.2 µg, P<0.05), MMP‐2 activity after LLLI was augmented (over non‐irradiated control) by 66±18% (2 J/cm2; P<0.05), and MMP‐1 gene expression upregulated. However, TIMP‐2 was upregulated, and MMP‐2 gene expression downregulated. IL‐1‐β gene expression was reduced.ConclusionsLLLI stimulates SMC proliferation, stimulates collagen synthesis, modulates the equilibrium between regulatory matrix remodeling enzymes, and inhibits pro‐inflammatory IL‐1‐β gene expression. These findings may be of therapeutic relevance for arterial diseases such as aneurysm where SMC depletion, weakened extracellular matrix, and an increase in pro‐inflammatory markers are major pathologic components. Lasers Surg. Med. 38:779–786, 2006. © 2006 Wiley‐Liss, Inc.
Side‐firing sealing caps for hollow optical fibers
Authors: Watanabe Tomonori , Matsuura Yuji 
Published: August 2006

AbstractBackground and ObjectivesHollow optical fibers are useful for delivery of high‐energy infrared laser beam such as Er:YAG lasers. We propose side‐firing optics for hollow optical fibers for laser endoscopic applications mainly in oto‐rhino‐laryngology and urology.Study Design/Materials and MethodsTo produce a circular beam, cone‐shaped caps are designed and caps with slanted end are proposed for producing a spot beam in side direction. Both types of caps are fabricated by fusing and polished Pyrex and silica glass tubes.ResultsFor the both of the cone‐shaped and slanted‐end caps effectively deflect laser beam as designed and these caps show high durability for Er:YAG laser light with pulse energy higher than 100 mJ.ConclusionsBy choosing the proper shape of the cap ends, these caps deflect an input laser beam to a preferred direction at low insertion losses. By using these side‐firing optics, one can easily irradiate the inside of tubular organs. Lasers Surg. Med. 38:792–797, 2006. © 2006 Wiley‐Liss, Inc.
Novel Water‐Soluble Shape‐Regulatable Luminescent Nanoparticles by Non‐Covalently Bonded Self‐Assembly
Authors: Zhang Zhi‐Jian , Zheng Zhe , Qiang Liang‐Liang , Ma Zhun , Xie Shi‐Xiang , Peng Bo , Huang Wei , Wei Wei 
Published: August 2006

AbstractSummary: Novel non‐covalently connected water‐soluble nanoparticles that contain poly(fluorene‐co‐phenylene) with hydroxy‐capped alkoxy side chains (PF3BOH) and poly(acrylic acid) (PAA) have been obtained and characterized. With different proportions of PF3BOH and PAA, the shape and size of the nanoparticles can be regulated. The nanoparticles are quite stable in water with no precipitate being observed after weeks. Transmission electron microscopy and dynamic laser light scattering are used to confirm the morphology of the PF3BOH/PAA nanoparticles. Their optical properties have been investigated and show similar optoelectronic properties to a PF3BOH solid film although they do not undergo aggregation.TEM images of the nanoparticles obtained upon varying the PAA/PF3BOH content.magnified imageTEM images of the nanoparticles obtained upon varying the PAA/PF3BOH content.
Cysteinyl‐leukotrienes and their receptors in asthma and other inflammatory diseases: Critical update and emerging trends
Authors: Capra Valérie , Thompson Miles D. , Sala Angelo , Cole David E. , Folco Giancarlo , Rovati G. Enrico 
Published: August 2006

AbstractCysteinyl‐leukotrienes (cysteinyl‐LTs), that is, LTC4, LTD4, and LTE4, trigger contractile and inflammatory responses through the specific interaction with G protein‐coupled receptors (GPCRs) belonging to the purine receptor cluster of the rhodopsin family, and identified as CysLT receptors (CysLTRs). Cysteinyl‐LTs have a clear role in pathophysiological conditions such as asthma and allergic rhinitis (AR), and have been implicated in other inflammatory conditions including cardiovascular diseases, cancer, atopic dermatitis, and urticaria. Molecular cloning of human CysLT1R and CysLT2R subtypes has confirmed most of the previous pharmacological characterization and identified distinct expression patterns only partially overlapping. Interestingly, recent data provide evidence for the immunomodulation of CysLTR expression, the existence of additional receptor subtypes, and of an intracellular pool of CysLTRs that may have roles different from those of plasma membrane receptors. Furthermore, genetic variants have been identified for the CysLTRs that may interact to confer risk for atopy. Finally, a crosstalk between the cysteinyl‐LT and the purine systems is being delineated. This review will summarize and attempt to integrate recent data derived from studies on the molecular pharmacology and pharmacogenetics of CysLTRs, and will consider the therapeutic opportunities arising from the new roles suggested for cysteinyl‐LTs and their receptors. © 2006 Wiley Periodicals, Inc. Med Res Rev, 27, No. 4, 469–527, 2007
Molecular aspects on the interaction of protoberberine, benzophenanthridine, and aristolochia group of alkaloids with nucleic acid structures and biological perspectives
Authors: Maiti Motilal , Kumar Gopinatha Suresh 
Published: August 2006

AbstractAlkaloids occupy an important position in chemistry and pharmacology. Among the various alkaloids, berberine and coralyne of the protoberberine group, sanguinarine of the benzophenanthridine group, and aristololactam‐β‐d‐glucoside of the aristolochia group have potential to form molecular complexes with nucleic acid structures and have attracted recent attention for their prospective clinical and pharmacological utility. This review highlights (i) the physicochemical properties of these alkaloids under various environmental conditions, (ii) the structure and functional aspects of various forms of deoxyribonucleic acid (DNA) (B‐form, Z‐form, HL‐form, protonated form, and triple helical form) and ribonucleic acid (RNA) (A‐form, protonated form, and triple helical form), and (iii) the interaction of these alkaloids with various polymorphic DNA and RNA structures reported by several research groups employing various analytical techniques like absorbance, fluorescence, circular dichroism, and NMR spectroscopy; electrospray ionization mass spectrometry, thermal melting, viscosity, and DNase footprinting as well as molecular modeling and thermodynamic studies to provide detailed binding mechanism at the molecular level for structure–activity relationship. Nucleic acids binding properties of these alkaloids are interpreted in relation to their biological activity. © 2006 Wiley Periodicals, Inc. Med Res Rev, 27, No. 5, 649–695, 2007
Preparation of enzymatically active human Myc‐tagged‐NCre recombinase exhibiting immunoreactivity with anti‐Myc antibody
Authors: Watanabe Satoshi , Honma Daisuke , Furusawa Tadashi , Sakurai Takayuki , Sato Masahiro 
Published: August 2006

AbstractThe Cre‐loxP system has been recognized as a tool for conditional gene targeting in mice. However, most anti‐Cre antibodies fail to react with Cre expressed in vivo. In an attempt to directly detect Cre by antibodies in vivo, we constructed the tagged‐NCre (NCreMH) gene by connecting the human Myc and His tag sequences to the 3′ end of the NCre gene carrying a nuclear localizing signal (NLS) sequence. The production of NCre protein and the recombinase activity were detected after co‐transfection with pCMV‐NCreMH and pCETZ‐17 carrying the loxP‐flanked lacZ gene into NIH3T3 cells. This activity was also confirmed in vivo after gene transfer of pCMV‐NCreMH and pCRTEIL‐6 carrying loxP‐flanked HcRed1 and EGFP cDNAs, into oviductal epithelium by electroporation. Immunohistochemical staining using anti‐Myc antibody demonstrated that the area positive for enhanced green fluorescent protein (EGFP) fluorescence was immunostained with the antibody. These findings indicate that NCreMH is useful as an alternative to NCre for gene targeting. Mol. Reprod. Dev. 73: 1345–1352, 2006. © 2006 Wiley‐Liss, Inc.
Induction of alpha‐caveolin‐1 (αCAV1) expression in bovine granulosa cells in response to an ovulatory dose of human chorionic gonadotropin
Authors: Diouf Mame Nahé , Lefebvre Réjean , Silversides David W. , Sirois Jean , Lussier Jacques G. 
Published: August 2006

AbstractCaveolins are implicated in endocytosis, cholesterol trafficking and signal transduction. A cDNA fragment corresponding to caveolin‐1 (CAV1) was identified in a mRNA profiling expression study in bovine granulosa cells (GC) following human chorionic gonadotropin (hCG)‐induced ovulation. Thus, we have characterized CAV1 cDNA and studied its spatio‐temporal expression pattern in bovine ovarian follicles. The full‐length bovine αCAV1 cDNA was cloned and encodes a putative 22 kDa protein. Expression of αCAV1 was studied in bovine GC obtained from follicles at different developmental stages: small follicles (SF: 2–4 mm), dominant follicles (DF), ovulatory follicles (OF: 24 hr post‐hCG), and corpus luteum (CL). Semiquantitative RT‐PCR analysis showed a 6.5‐fold increase in αCAV1 mRNA in GC of OF versus DF (P < 0.0001), whereas CAV2 mRNA was increased by only twofold (P < 0.0007). Temporal expression of αCAV1 mRNA from OF recovered at 0, 6, 12, 18, and 24 hr after hCG injection showed an 8.5‐fold increase of αCAV1 mRNA after 24 hr compared to 0 hr (P < 0.0018) whereas no significant variation was detected for CAV2. Immunoblot demonstrated an initial increase in αCAV1 protein level 12 hr post‐hCG, reaching a maximum at 24 hr. Immunohistochemical localization of CAV1 was observed in GC of OF isolated 18 and 24 hr after hCG injection, whereas no signal was detected in GC of DF and SF. The induction of αCAV1 in GC of OF suggests that αCAV1 likely contributes to control the increase in membrane signaling that occurs at the time of ovulation and luteinization. Mol. Reprod. Dev. 73: 1353–1360, 2006. © 2006 Wiley‐Liss, Inc.
The transcription factor CREMτ and cAMP regulate promoter activity of the Na,K‐ATPase α4 isoform
Authors: Rodova Marianna , Nguyen Anh‐Nguyet , Blanco Gustavo 
Published: August 2006

AbstractThe Na,K‐ATPase is an essential enzyme of the plasma membrane that plays a key role in numerous cell processes that depend on the transcellular gradients of Na+ and K+. Among the various isoforms of the catalytic subunit of the Na,K‐ATPase, α4 exhibits the most limited pattern of expression, being restricted to male germ cells. Activity of α4 is essential for sperm function, and α4 is upregulated during spermatogenesis. The present study addressed the transcriptional control of the human Na,K‐ATPase α4 gene, ATP1A4. We describe that a 5′ untranslated region of the ATP1A4 gene (designated −339/+480 based on the ATP1A4 transcription initiation site) has promoter activity in luciferase reporter assays. Computer analysis of this promoter region revealed consensus sites (CRE) for the cyclic AMP (cAMP) response element modulator (CREM). Accordingly, dibutyryl cAMP (db‐cAMP) and ectopic expression of CREMτ, a testis specific splice variant of CREM were able to activate the ATP1A4 promoter driven expression of luciferase in HEK 293 T, JEG‐3 and GC‐1 cells. Further characterization of the effect of db‐cAMP and CREMτ on deleted constructs of the ATP1A4 promoter (−339/+80, and +25/+480), and on the −339/+480 region carrying mutations in the CRE sites showed that db‐cAMP and CREMτ effect required the CRE motif located 263 bp upstream the transcription initiation site. EMSA experiments confirmed the CRE sequence as a bonafide CREMτ binding site. These results constitute the first demonstration of the transcriptional control of ATP1A4 gene expression by cAMP and by CREMτ, a transcription factor essential for male germ cell gene expression. Mol. Reprod. Dev. 73: 1435–1447, 2006. © 2006 Wiley‐Liss, Inc.
Hyperactivation is the mode conversion from constant‐curvature beating to constant‐frequency beating under a constant rate of microtubule sliding
Authors: Ohmuro Junko , Ishijima Sumio 
Published: August 2006

AbstractFlagellar beating of hyperactivated golden hamster spermatozoa was analyzed in detail using digital image analysis and was compared to that of nonhyperactivated (activated) spermatozoa in order to understand the change in flagellar beating during hyperactivation and the active microtubule sliding that brought about the change in flagellar beating. Hyperactivated flagellar beating, which was characterized by a sharp bend in the proximal midpiece and low beat frequency, was able to alter the waveform with little change in beat frequency (constant‐frequency beating), whereas activated flagellar beating, which was characterized by a slight bend in the proximal midpiece and high beat frequency, was able to alter beat frequency with little change in the waveform (constant‐curvature beating). These results demonstrate that flagellar beating of hyperactivated and activated spermatozoa were essentially different modes and that hyperactivation was the mode conversion from constant‐curvature beating to constant‐frequency beating. Detailed analysis of flagellar bends revealed that the increase in curvature in the proximal midpiece during hyperactivation was due to the increase in total length of microtubule sliding in a nearly straight region between bends, while the rate of microtubule sliding remained almost constant. Mol. Reprod. Dev. 73: 1412–1421, 2006. © 2006 Wiley‐Liss, Inc.
Developmental expression of pluripotency determining factors in caprine embryos: Novel pattern of NANOG protein localization in the nucleolus
Authors: He Shuyang , Pant Disha , Schiffmacher Andrew , Bischoff Steve , Melican David , Gavin William , Keefer Carol 
Published: August 2006

AbstractTranscription factors, POU5F1/OCT4 and NANOG, whose expression is restricted to the inner cell mass (ICM) in mouse and human blastocysts, are used to characterize undifferentiated embryonic stem cells (ESC) in vitro. However, POU5F1 may not be a useful marker in domestic animals due to its expression in both ICM and trophectoderm (TE), while NANOG mRNA and protein expression have only been described fully in mice. In an effort to identify ESC markers for domestic animals, expression patterns of NANOG, POU5F1, and the cell surface markers (SSEA1, SSEA4, TRA‐1‐60, TRA‐1‐81) were examined in preimplantation goat embryos, a species that has proven to be a superior choice for the production of transgenic proteins in milk (biopharming). Our results indicate that while goat embryos express POU5F1, SSEA1, and SSEA4 proteins, their expression is not strictly restricted to the ICM. In a unique staining pattern, NANOG protein was localized to the nucleoplasm and nucleoli in ICM cells, but was localized strictly to nucleoli in TE. This pattern may reflect down‐regulation of protein by sequestration/degradation utilizing a nucleolar mechanism known to operate in stem cells. Furthermore, NANOG mRNA in TE was also significantly down‐regulated as compared with that in ICM. Taken together, this novel expression pattern of NANOG in goat preimplantation embryos suggests that NANOG could serve as marker of pluripotency in goats and may be useful in derivation and characterization of caprine ESC. This study is the first to characterize both NANOG mRNA and protein expression in any species other than the mouse. Mol. Reprod. Dev. 73: 1512–1522, 2006. © 2006 Wiley‐Liss, Inc.
Gamete interaction: Is it species‐specific?
Authors: Vieira Ana , Miller David J. 
Published: August 2006

AbstractReproductive isolation is pivotal to maintain species separation and it can be achieved through a plethora of mechanisms. In addition, the development of barriers to gamete interaction may drive speciation. Such barriers to interspecific gamete interaction can be prezygotic or postzygotic. Considering the great diversity in animal species, it is easy to assume that regulation of the early steps of fertilization is critical to maintain species identity. One prezygotic mechanism that is often mentioned in the literature is that gamete interaction is limited to gametes of the same species. But do gametes of all animals interact in a species‐specific way? Are gamete interactions completely species‐specific or perhaps just species‐restricted? In species in which species‐restrictions have been described, is the interspecies barrier at one major step in the fertilization process or is it a combination of partially restricted steps that together lead to a block in interspecific fertilization? Are the mechanisms used to avoid interspecific crosses different between free‐spawning organisms and those with internal fertilization? This review will address these questions, focusing on prezygotic barriers, and will describe what is known about the molecular biology that may account for species‐limited gamete recognition and fertilization. Mol. Reprod. Dev. 73: 1422–1429, 2006. © 2006 Wiley‐Liss, Inc.
The mammalian acrosome as a secretory lysosome: New and old evidence
Authors: Moreno Ricardo D , Alvarado Carlos P 
Published: August 2006

AbstractThe morphological and biochemical characteristics of the acrosome depart well from any other vesicles in somatic cells, making it one of a kind amongst secretory vesicles. The components of the acrosome include a mixture of unique enzymes like acrosin and other enzymes that when present in somatic cells are commonly found in lysosomes, peroxisomes, and even in the cytoplasm. Several observations have pointed out that acrosomal biogenesis has unique features not previously described in secretory vesicle biogenesis of somatic cells. In this review we discuss the evidence supporting a molecular link between the machinery involved in lysosome and acrosome biogenesis, link which may help account for the acrosome unique composition. Mol. Reprod. Dev. 73: 1430–1434, 2006. © 2006 Wiley‐Liss, Inc.