bluuebunny/crossref_metadata_2025_split huggingface dataset:
Blood platelet production: a novel approach for practical optimization
Authors: Van Dijk Nico , Haijema René , Van Der Wal Jan , Sibinga Cees Smit 
Published: January 2009

BACKGROUND: The challenge of production and inventory management for blood platelets (PLTs) is the requirement to meet highly uncertain demands. Shortages are to be minimized, if not to be avoided at all. Overproduction, in turn, leads to high levels of outdating as PLTs have a limited “shelf life.” Outdating is to be minimized for ethical and cost reasons.STUDY DESIGN AND METHODS: Operations research (OR) methodology was applied to the PLT inventory management problem. The problem can be formulated in a general mathematical form. To solve this problem, a five‐step procedure was used. This procedure is based on a combination of two techniques, a mathematical technique called stochastic dynamic programming (SDP) and computer simulation.RESULTS: The approach identified an optimal production policy, leading to the computation of a simple and nearly optimal PLT production “order‐up‐to” rule. This rule prescribes a fixed order‐up‐to level for each day of the week. The approach was applied to a test study with actual data for a regional Dutch blood bank. The main finding in the test study was that outdating could be reduced from 15‐20 percent to less than 0.1 percent with virtually no shortages. Blood group preferences and extending the shelf life of more than 5 days appeared to be of marginal effect.CONCLUSION: In this article the worlds of blood management and the mathematical discipline of OR are brought together for the optimization of blood PLT production. This leads to simple nearly optimal blood PLT production policies that are suitable for practical implementation.
Ontogenetic changes in the shelter site of a leaf‐folding caterpillar, Vanessa indica
Authors: Ide Jun‐Ya 
Published: January 2009

AbstractFactors responsible for ontogenetic habitat shifts were examined using larvae of the Indian red admiral butterfly, Vanessa indica (Herbst) (Lepidoptera: Nymphalidae). The larvae of V. indica fold leaves of China ramie, Boehmeria nipononivea Koidz. (Urticaceae), to form shelters that also serve as food. When constructing shelters, old larvae (usually third instar or older) frequently cut trenches at the bases of the leaves, whereas younger larvae do not. This trenching behaviour reduces the force required to fold large ramie leaves. Young larvae used small apical leaves as shelter sites. Once larvae were capable of cutting trenches, they moved proximally on the host plant and used middle leaves that either had completed or were about to complete expansion. Results of bioassays revealed that, for young larvae, apical and middle leaves did not differ in food quality. In contrast, for older larvae, the quality of middle leaves was higher than that of apical leaves. These observations suggest that young larvae decrease the risk of predation during shelter construction by using apical leaves that are relatively easy to fold, and that old larvae employ trenching to decrease the duration of leaf folding and improve growth rate by using middle leaves that are of high quality. Thus, the facilitation of leaf‐folding by trenching is considered to reduce the necessity of using apical leaves, and the acquisition of the trenching ability triggers an ontogenetic shift in the selection of larval shelter sites.
Effects of age and repeated mating on male sperm supply and paternity in a parasitoid wasp
Authors: Bressac Christophe , Thi Khanh Hong Do , Chevrier Claude 
Published: January 2009

AbstractPost‐copulatory paternity biases after female multiple mating are major constraints on both male and female reproductive systems. The outcome of paternity in certain situations is only controlled directly by male sperm stock. This was tested experimentally in the parasitoid wasp Anisopteromalus calandrae (Howard) (Hymenoptera: Pteromalidae), in which sperm stocks are small (several hundred) and the fertilizing efficiency of stored sperm is high (the ratio of sperm stored/fertilized eggs is about 0.75). Sperm in seminal vesicles and paternity of males of different status (virgin young, virgin old, or young previously mated) were measured after female single and double mating. The amount of sperm in the seminal vesicle differed according to male status (increasing from previously mated males to old males), but there was no difference in sperm stored by females after a single mating. In double mating experiments with two males of different status, paternity increased linearly with the relative amount of sperm in seminal vesicles. Paternity distribution conforms to ‘a fair raffle’ of sperm from both donors following complete mixing of sperm prior to fertilization. Thus, in a female multiple mating context, male fitness depends principally on their sperm stock, which in turn depends on life history parameters, such as age and previous mating.
Characterization and correlation of DC electrical penetration graph waveforms with feeding behavior of beet leafhopper, Circulifer tenellus
Authors: Stafford C. A. , Walker G. P. 
Published: January 2009

AbstractFeeding behavior of beet leafhopper, Circulifer tenellus (Baker) (Homoptera: Cicadellidae), was studied with a DC electrical penetration graph. Nine different electrical penetration graph waveforms associated with feeding were identified and characterized. Waveforms were correlated with specific feeding behaviors using a number of techniques, including high magnification video recording, honeydew analysis, stylectomy, and histological processing. Waveforms were grouped into three phases based on feeding behavior: pathway phase (waveforms A, B1, B2, and C), non‐phloem ingestion phase (waveform G), and phloem phase (waveforms D1, D2, D3, and D4). No ingestion was found to occur during waveforms A, B1, B2, and C. Waveform G was associated primarily with ingestion of xylem sap and occasionally with ingestion of mesophyll sap. Stylet tips were located in phloem during waveforms D1, D2, and D3, and waveforms D2 and D3 were correlated with ingestion of phloem sap. Waveform D4 probably also plays a role in phloem ingestion, because D4 is very brief and always occurs embedded in either waveform D2 or D3. In contrast to most other homopteran insects, rate of honeydew production (and hence rate of ingestion) was much lower on phloem than on xylem. More rapid rates of ingestion are expected on phloem, because its high turgor pressure drives sap into the feeding insect whereas the negative pressure of xylem sap is expected to cause a slow rate of ingestion. The very slow ingestion rate of beet leafhopper feeding on phloem suggests that it is not able to exploit the high turgor pressure of phloem to achieve the high rate of ingestion that is typical of phloem ingestion by other insects.
The Kazal motifs of RECK protein inhibit MMP‐9 secretion and activity and reduce metastasis of lung cancer cells in vitro and in vivo
Authors: Chang Chong‐Keng , Hung Wen‐Chun , Chang Hui‐Chiu 
Published: January 2009

AbstractRECK is a membrane‐anchored glycoprotein which may negatively regulate matrix metalloproteinase (MMP) activity to suppress tumor invasion and metastasis. In this study, recombinant proteins corresponding to the residues 285–368 (named as CKM which contained cysteine knot motif), 605–799 (named as K123 which contained three Kazal motifs), 676–799 (named as K23 which contained the last two Kazal motifs) and full‐length RECK were produced and their anti‐cancer effects were tested. Full‐length RECK and K23 but not K123 and CKM inhibited MMP9 secretion and activity. In addition, RECK and K23 inhibited invasion but not migration of metastatic lung cancer cells in vitro. Protein binding and kinetic study indicated that K23 physically interacted with MMP‐9 and inhibited its activity by a non‐competitive manner. Moreover, K23 reduced metastatic tumor growth in lungs of nude mice. Taken together, our results suggest that the K23 motifs of RECK protein can inhibit MMP‐9 secretion and activity and attenuate metastasis of lung cancer cells.
ZHX2 is a repressor of α‐fetoprotein expression in human hepatoma cell lines
Authors: Shen H. , Luan F. , Liu H. , Gao L. , Liang X. , Zhang L. , Sun W. , Ma C. 
Published: January 2009

AbstractThe zinc‐fingers and homeoboxes 2 (ZHX2) protein was shown previously to be involved in postnatal repression of α‐fetoprotein (AFP) in mice. More recently, loss of ZHX2 expression was often found in human hepatcellular carcinoma (HCC), where AFP is frequently reactivated. Using HepG2 and HepG2.2.15, which express high AFP levels, we show that ZHX2 overexpression significantly decreases of AFP secretion in a dose dependent manner. Furthermore, using LO2 and SMMC7721 cells, which express low AFP levels, we use siRNA inhibition to show that AFP is de‐repressed when ZHX2 levels are reduced. This represents the first direct evidence that ZHX2 represses AFP. Co‐transfections of ZHX2 and AFP‐luciferase reporter genes demonstrate ZHX2 repression is governed by the AFP promoter and requires intact HNF1 binding sites. These data support the idea that ZHX2 contributes to AFP repression in the liver after birth and may also be involved in AFP reactivation in liver cancer.
Experimental melanoma metastasis in lungs of mice with congenital coagulation disorders
Authors: Brüggemann Lois W. , Versteeg Henri H. , Niers Tatjana M. , Reitsma Pieter H. , Spek C. Arnold 
Published: January 2009

AbstractExperimental animal studies as well as clinical trials have shown that interventions targeting the blood coagulation cascade inhibit cancer cell metastasis. These data support the hypothesis that congenital prothrombotic disorders, like factor V Leiden, facilitate metastasis whereas bleeding disorders, like haemophilia impede metastasis. To test this hypothesis, we subjected factor V Leiden and factor VIII deficient mice to a murine model of experimental lung metastasis. In this model, B16F10 murine melanoma cells are injected into the tail vein resulting in multiple lung metastases within 20 days. Both hemi‐ and homozygous factor VIII deficient mice were protected against lung metastasis compared to wild‐type littermate controls. In contrast, homozygous factor V Leiden mice developed more metastases than wild‐type littermates, whereas heterozygous carriers showed an intermediate number of pulmonary foci. Overall, these data show that a congenital susceptibility to either bleeding or thrombosis modifies the metastatic capacity of cancer cells in the bloodstream and suggest that procoagulant phenotypes are a risk factor for tumour metastasis.
Human gingival fibroblasts are critical in sustaining inflammation in periodontal disease
Authors: Ara Toshiaki , Kurata Kazuyuki , Hirai Kaname , Uchihashi Takayuki , Uematsu Takashi , Imamura Yasuhiro , Furusawa Kiyohumi , Kurihara Saburo , Wang Pao‐Li 
Published: January 2009

Background and Objective:  A major factor in the pathogenesis of periodontal disease, which is one of the biofilm infectious diseases, is thought to be lipopolysaccharide (LPS), owing to its ability to cause inflammation and promote tissue destruction. Moreover, the elimination of pathogens and their component LPSs is essential for the successful treatment of periodontal disease. Lipopolysaccharide tolerance is a mechanism that prevents excessive and prolonged responses of monocytes and macrophages to LPS. Since persistence of inflammation is necessary for inflammatory cytokine production, cells other than monocytes and macrophages are thought to maintain the production of cytokines in the presence of LPS. In this study, we investigated whether human gingival fibroblasts (HGFs), the most abundant structural cell in periodontal tissue, might be able to maintain inflammatory cytokine production in the presence of LPS by not displaying LPS tolerance.Material and Methods:  Human gingival fibroblasts were pretreated with LPS (from Porphyromonas gingivalis and Escherichia coli) and then treated with LPS, and the amounts of interleukin (IL)‐6 and IL‐8 in the cell culture supernatants were measured. The expression of negative regulators of LPS signalling (suppressor of cytokine signalling‐1, interleukin‐1 receptor‐associated‐kinase M and SH2 domain‐containing inositol‐5‐phosphatase‐1) was also examined in LPS‐treated HGFs.Results:  Human gingival fibroblasts did not display LPS tolerance but maintained production of IL‐6 and IL‐8 when pretreated with LPS, followed by secondary LPS treatment. Lipopolysaccharide‐treated HGFs did not express negative regulators.Conclusion:  These results demonstrate that HGFs do not show LPS tolerance and suggest that this characteristic of HGFs sustains the inflammatory response in the presence of virulence factors.
Effects of smoking on the ex vivo cytokine production in periodontitis
Authors: Torres de Heens G. L. , Kikkert R. , Aarden L. A. , Van Der Velden U. , Loos B. G. 
Published: January 2009

Background and Objective:  Smoking is associated with increased severity of periodontitis. The underlying mechanisms of this phenomenon are not well understood. The purpose of the present study was to compare the monocyte‐derived T cell directing (Th1/Th2) response and pro‐inflammatory cytokine production in ex vivo whole blood cell cultures (WBCC) of smoking and non‐smoking chronic periodontitis patients.Material and Methods:  Venous blood was collected from 29 periodontitis patients (18 non‐smokers and 11 smokers) receiving supportive periodontal treatment, and diluted 10‐fold for WBCC. The WBCC were stimulated for 18 h with Neisseria meningitidis lipo‐oligosaccharide (LOS) orPorphyromonas gingivalis sonic extract (Pg‐SE). The production of the T cell directing cytokines interleukin (IL)‐12 p40 and IL‐10, as well as the pro‐inflammatory cytokines IL‐1β, IL‐6 and IL‐8, was measured in the culture supernatants.Results:  After LOS stimulation of WBCC, smokers showed a lower IL‐12 p40/IL‐10 ratio than non‐smokers (P < 0.05). Interleukin‐1β production was significantly lower in smokers compared with non‐smokers after stimulation with either LOS or Pg‐SE (P < 0.05). Interleukin‐6 and IL‐8 production was similar in WBCC from both smokers and non‐smokers, for both LOS and Pg‐SE.Conclusion:  A more pronounced Th2 response in smoking periodontitis patients may be related to increased severity of the disease.
Tumor necrosis factor‐α‐stimulated membrane type 1‐matrix metalloproteinase production is modulated by epidermal growth factor receptor signaling in human gingival fibroblasts
Authors: Smith P. C. , Guerrero J. , Tobar N. , Cáceres M. , González M. J. , Martínez J. 
Published: January 2009

Background and Objectives:  Membrane type 1‐matrix metalloproteinase (MT1‐MMP) is a collagenolytic enzyme involved in connective tissue remodeling. In periodontal tissues, either cytokines or growth factors regulate the production of proteolytic enzymes. Mice deficient in epidermal growth factor receptor (EGFR) show a reduced expression of MT1‐MMP, suggesting that this receptor may play an important role in MT1‐MMP production. The present study evaluated the role of the inflammatory cytokine tumor necrosis factor‐α (TNF‐α) and EGFR in the production of MT1‐MMP in gingival fibroblasts.Material and Methods:  Primary cultures of human gingival fibroblasts were cultured over plastic or a type I collagen matrix and stimulated with TNF‐α and EGF. A selective EGFR inhibitor (AG1478) was used to interfere with this signaling pathway. Production of MT1‐MMP and activation of proMMP‐2 were studied using Western blot and gelatin zymography, respectively. Activation of EGFR signaling was assessed through immunoprecipitation and Western blot. Expression of EGFR ligands was determined through reverse transcriptase‐polymerase chain reaction.Results:  Treatment of gingival fibroblasts cultured over a collagen matrix with TNF‐α stimulated proMMP‐2 activation and MT1‐MMP production. However, after using AG1478, both responses were inhibited. Tumor necrosis factor‐α induced EGFR transactivation and stimulated the expression of the mRNA for the EGFR ligands heparin binding‐epidermal growth factor (HB‐EGF) and transforming growth factor‐α (TGF‐α).Conclusions:  The present study shows that TNF‐α may stimulate MT1‐MMP production through transactivation of EGFR. Tumor necrosis factor‐α may also modulate the expression of the EGFR ligands TGF‐α and HB‐EGF. Production of MT1‐MMP by TNF‐α requires interaction with EGFR, suggesting that tissue remodeling is controlled by cross‐communication between diverse signaling pathways in gingival fibroblasts.
Human leukocyte histocompatibility antigen class II‐induced cytokines from human gingival fibroblasts promote proliferation of human umbilical vein endothelial cells: potential association with enhanced angiogenesis in chronic periodontal inflammation
Authors: Okada Y. , Meguro M. , Ohyama H. , Yoshizawa S. , Takeuchi‐Hatanaka K. , Kato N. , Matsushita S. , Takashiba S. , Nishimura F. 
Published: January 2009

Background and Objective:  The role of human leukocyte histocompatibility antigen (HLA) class II molecules on non‐antigen‐presenting cells has been a matter of controversy. We previously reported that HLA‐II molecules on human gingival fibroblasts (GF) do not present antigens, but transduce signals into the cells, resulting in the expression of several cytokines, such as interleukin‐6 (IL‐6), monocyte chemoattractant protein‐1 (MCP‐1), regulated upon activation, normal T‐cell expressed and secreted (RANTES) and IL‐8. However, the exact role of these cytokines, as well as other cytokines which are potentially secreted from GF, in the pathogenesis of chronic periodontal inflammation is not fully understood. The aim of this study was to observe the effects of HLA‐II‐induced cytokines on the proliferation of human umbilical vein endothelial cells (HUVEC).Material and Methods:  Antibody‐based cytokine‐microarray analyses were performed to detect potential cytokines associated with angiogenesis. Next, cytokine productivity was confirmed by quantitative methods. Then, cell proliferation assay was performed to see whether these cytokines promoted the proliferation of HUVEC.Results:  Besides IL‐6, MCP‐1, RANTES and IL‐8, growth‐related gene product (GRO) was newly identified as an HLA‐II‐induced cytokine released from GF. This was confirmed by a quantitative method. Cell culture supernatant from HLA‐II‐stimulated GF cultures promoted the growth of HUVEC. Addition of anti‐IL‐8 neutralizing antibody, anti‐CXC receptor (CXCR)1 antibody and anti‐MCP‐1 antibody inhibited the growth of HUVEC in a dose‐dependent manner, while addition of anti‐GROα antibody did not.Conclusion:  The HLA‐II‐induced IL‐8, via CXCR1, as well as MCP‐1 from GF, promotes endothelial cell proliferation, which is possibly associated with enhanced angiogenesis in chronic periodontal lesions.
Increased expression of extracellular matrix metalloproteinase inducer is associated with matrix metalloproteinase‐1 and ‐2 in gingival tissues from patients with periodontitis
Authors: Dong W. , Xiang J. , Li C. , Cao Z. , Huang Z. 
Published: January 2009

Background and Objective:  Extracellular matrix metalloproteinase inducer (EMMPRIN), an immunoglobulin‐like cell surface glycoprotein, could promote collagenolytic balance in favor of the expression and activation of matrix metalloproteinases (MMPs). This study was to investigate the expression of EMMPRIN in gingival tissues from different periodontal conditions and to correlate it with the production of MMP‐1 and MMP‐2.Material and Methods:  Gingival biopsies were collected from 15 patients with untreated advanced chronic periodontitis and 15 patients with aggressive periodontitis (AgP). The control group consisted of 12 subjects diagnosed either as periodontally healthy individuals or as individuals with a gingival index of one (H/G1). The peptides and mRNA of EMMPRIN, MMP‐1 and MMP‐2 were detected by immunohistochemistry and semi‐quantitative reverse transcriptase‐polymerase chain reaction, respectively.Results:  The expression of EMMPRIN, MMP‐1 and MMP‐2 peptides in periodontally healthy tissues was mainly confined to the gingival epithelium. The EMMPRIN was strongly expressed in the cell membrane of the basal layer. Immunoreactivity for EMMPRIN was more intensive and more widespread in periodontitis, extended from the epithelial layers to the underlying connective tissues, and was essential in both inflammatory and fibroblast‐like cells. In addition, MMP‐1 and MMP‐2 showed the same localized expression. The chronic periodontitis group had a significantly higher mRNA expression of EMMPRIN and MMP‐2 compared with the H/G1 subjects (p < 0.05). Production of MMP‐1 and MMP‐2 by gingival tissues was correlated with the mRNA level of EMMPRIN (r = 0.463, p = 0.013 for MMP‐1 and r = 0.404, p = 0.033 for MMP‐2).Conclusion:  The expression of EMMPRIN in human normal and diseased gingiva might contribute to periodontal physiological and pathological processes; moreover, its increased production might be associated with MMP‐1 and MMP‐2 expression.
Comparative gender differences in local and systemic concentrations of pro‐inflammatory cytokines in rats with experimental periodontitis
Authors: Bain J. L. , Lester S. R. , Henry W. D. , Bishop C. M. , Turnage A. A. , Naftel J. P. , Johnson R. B. 
Published: January 2009

Background and Objective:  There have been few studies of gender differences in response to periodontitis. Thus, we compared gender‐specific differences in systemic cytokine concentrations in rats with and without ligature‐induced periodontitis.Material and Methods:  Experimental periodontal disease was initiated in Sprague–Dawley rats by placing a ligature around the crowns of the second right maxillary molar tooth. Sham‐operated control groups were also created. Two weeks later, the right and left maxillary quadrants of teeth, liver and serum were collected from all the rats, and uterine horns were collected from the female rats. Liver and uterine samples were ground in phosphate‐buffered saline (10 mg of tissue/mL of phosphate‐buffered saline + protease inhibitor) containing a protease inhibitor, and cytokine concentrations were determined by enzyme‐linked immunosorbent assay. Digital radiographs were made of maxillary quadrants, and the distance from cemento–enamel junction to alveolar crest was measured using image analysis software. Data were compared by factorial analysis of variance and a post‐hoc Tukey test.Results:  Female rats with ligatures had greater, but not significantly different, alveolar bone loss than males with ligatures. However, they had higher serum concentrations of interleukin‐6, tumor necrosis factor‐α and C‐reactive protein, and liver C‐reactive protein (p < 0.05). These females also had higher interleukin‐6, tumor necrosis factor‐α and vascular endothelial growth factor concentrations within the uterine horn, compared to female controls (p < 0.05). Male animals with ligatures had lower serum concentrations of C‐reactive protein and higher interleukin‐6 and tumor necrosis factor‐α concentrations within serum, compared to male controls (p < 0.05).Conclusion:  Our study suggests that females with periodontal disease have a greater risk for inflammatory‐based systemic diseases than males.