bluuebunny/crossref_metadata_2025 huggingface dataset:
An intelligent diabetes classification and perception framework based on ensemble and deep learning method
Authors: Waqas Khan Qazi , Iqbal Khalid , Ahmad Rashid , Rizwan Atif , Nawaz Khan Anam , Kim DoHyeun
Published: March 2024

Sugar in the blood can harm individuals and their vital organs, potentially leading to blindness, renal illness, as well as kidney and heart diseases. Globally, diabetic patients face an average annual mortality rate of 38%. This study employs Chi-square, mutual information, and sequential feature selection (SFS) to choose features for training multiple classifiers. These classifiers include an artificial neural network (ANN), a random forest (RF), a gradient boosting (GB) algorithm, Tab-Net, and a support vector machine (SVM). The goal is to predict the onset of diabetes at an earlier age. The classifier, developed based on the selected features, aims to enable early diagnosis of diabetes. The PIMA and early-risk diabetes datasets serve as test subjects for the developed system. The feature selection technique is then applied to focus on the most important and relevant features for model training. The experiment findings conclude that the ANN exhibited a spectacular performance in terms of accuracy on the PIMA dataset, achieving a remarkable accuracy rate of 99.35%. The second experiment, conducted on the early diabetes risk dataset using selected features, revealed that RF achieved an accuracy of 99.36%. Based on our experimental results, it can be concluded that our suggested method significantly outperformed baseline machine learning algorithms already employed for diabetes prediction on both datasets.
Password authenticated key exchange-based on Kyber for mobile devices
Authors: Seyhan Kübra , Akleylek Sedat , Dursun Ahmet Faruk
Published: March 2024

In this article, a password-authenticated key exchange (PAKE) version of the National Institute of Standards and Technology (NIST) post-quantum cryptography (PQC) public-key encryption and key-establishment standard is constructed. We mainly focused on how the PAKE version of PQC standard Kyber with mobile compatibility can be obtained by using simple structured password components. In the design process, the conventional password-based authenticated key exchange (PAK) approach is updated under the module learning with errors (MLWE) assumptions to add password-based authentication. Thanks to the following PAK model, the proposed Kyber.PAKE provides explicit authentication and perfect forward secrecy (PFS). The resistance analysis against the password dictionary attack of Kyber.PAKE is examined by using random oracle model (ROM) assumptions. In the security analysis, the cumulative distribution function (CDF) Zipf (CDF-Zipf) model is also followed to provide realistic security examinations. According to the implementation results, Kyber.PAKE presents better run-time than lattice-based PAKE schemes with similar features, even if it contains complex key encapsulation mechanism (KEM) components. The comparison results show that the proposed PAKE scheme will come to the fore for the future security of mobile environments and other areas.
Higher body condition with infection by Haemoproteus parasites in Bananaquits (Coereba flaveola)
Authors: Gutiérrez-Ramos Nicole A. , Acevedo Miguel A.
Published: March 2024

Parasite transmission is a heterogenous process in host-parasite interactions. This heterogeneity is particularly apparent in vector-borne parasite transmission where the vector adds an additional level of complexity. Haemosporidian parasites, a widespread protist, cause a malaria-like disease in birds globally, but we still have much to learn about the consequences of infection to hosts’ health. In the Caribbean, where malarial parasites are endemic, studying host-parasites interactions may give us important insights about energetic trade-offs involved in malarial parasites infections in birds. In this study, we tested the consequences of Haemoproteus infection on the Bananaquit, a resident species of Puerto Rico. We also tested for potential sources of individual heterogeneity in the consequences of infection such as host age and sex. To quantify the consequences of infection to hosts’ health we compared three complementary body condition indices between infected and uninfected individuals. Our results showed that Bananaquits infected by Haemoproteus had higher body condition than uninfected individuals. This result was consistent among the three body condition indices. Still, we found no clear evidence that this effect was mediated by host age or sex. We discuss a set of non-mutually exclusive hypotheses that may explain this pattern including metabolic syndrome, immunological responses leading to host tolerance or resistance to infection, and potential changes in consumption rates. Overall, our results suggest that other mechanisms, may drive the consequences of avian malarial infection.
First record of Apanteles hemara (N.) on Leucinodes orbonalis Guenée and biodiversity of Hymenoptera parasitoids on Brinjal
Authors: Saleh Hager M. M. , Al-Khalaf Areej A. , Alwaili Maha Abdullah , Dey Debjani
Published: March 2024

The brinjal fruit and shoot borer (BFSB), Leucinodes orbonalis Guenée (Lepidoptera: Crambidae), is a very detrimental pest that causes significant economic losses to brinjal crop worldwide. Infested brinjal fruits were collected from vegetable fields located at the ICAR-Indian Agricultural Research Institute (ICAR-IARI), New Delhi, India, during two consecutive seasons (2021–2022). The larvae of the pest were brought to the laboratory and reared under controlled conditions of 25 ± 0.5 °C and 70 ± 5% relative humidity, for the emergence of parasitoids. In addition, the survey of Hymenoptera parasitoids in brinjal was conducted utilizing a sweep net and yellow pan trap over the course of two seasons. The results reveal that five parasitoid species were emerged from L. orbonalis viz., Apanteles hemara Nixon, 1965, Bracon greeni Ashmead 1896 (Hymenoptera: Braconidae), Goryphus nursei (Cameron, 1907), Trathala flavoorbitalis (Cameron, 1907) (Hymenoptera: Ichneumonidae) and Spalangia gemina Boucek 1963 (Hymenoptera: Spalangiidae). Out of these, A. hemara and S. gemina were documented as new occurrences in Delhi. Additionally, A. hemara was recorded for the first time as a parasite on L. orbonalis. Trathala flavoorbitalis was observed during both seasons and exhibited higher parasitism reaching 15.55% and 18.46% in July and August 2022, respectively. However, the average parasitism (%) recorded by A. hemara, B. greeni, G. nursei, T. flavoorbitalis and S. gemina was 3.10%, 1.76%, 1.10%, 9.28% and 1.20% respectively. Furthermore, the findings showed a significant (p ≤ 0.01) strongly positive correlation between fruit infestation (%) by L. orbonalis and parasitism (%). The survey indicates the presence of a broad group (19 families and 60 species) of Hymenoptera parasitoids in the brinjal crop ecosystem in Delhi which could be valuable in biological control. In light of these results, this study revealed that A. hemara and other parasitoids identified in this study alongside T. flavoorbitalis would be ideal biocontrol agents within the integrated pest management (IPM) program of BFSB in Delhi.
In the social amoeba Dictyostelium discoideum, shortened stalks may limit obligate cheater success even when exploitable partners are available
Authors: Medina James , Larsen Tyler , Queller David C. , Strassmann Joan E.
Published: March 2024

Cooperation is widespread across life, but its existence can be threatened by exploitation. The rise of obligate social cheaters that are incapable of contributing to a necessary cooperative function can lead to the loss of that function. In the social amoeba Dictyostelium discoideum, obligate social cheaters cannot form dead stalk cells and in chimeras instead form living spore cells. This gives them a competitive advantage within chimeras. However, obligate cheaters of this kind have thus far not been found in nature, probably because they are often enough in clonal populations that they need to retain the ability to produce stalks. In this study we discovered an additional cost to obligate cheaters. Even when there are wild-type cells to parasitize, the chimeric fruiting bodies that result have shorter stalks and these are disadvantaged in spore dispersal. The inability of obligate cheaters to form fruiting bodies when they are on their own combined with the lower functionality of fruiting bodies when they are not represent limits on obligate social cheating as a strategy.
Predicting the current fishable habitat distribution of Antarctic toothfish (Dissostichus mawsoni) and its shift in the future under climate change in the Southern Ocean
Authors: Liu Jie , Zhu Ancheng , Wang Xitao , Zhou Xiangjun , Chen Lu
Published: March 2024

Global warming continues to exert unprecedented impacts on marine habitats. Species distribution models (SDMs) are proven powerful in predicting habitat distribution for marine demersal species under climate change impacts. The Antarctic toothfish, Dissostichus mawsoni (Norman 1937), an ecologically and commercially significant species, is endemic to the Southern Ocean. Utilizing occurrence records and environmental data, we developed an ensemble model that integrates various modelling techniques. This model characterizes species-environment relationships and predicts current and future fishable habitats of D. mawsoni under four climate change scenarios. Ice thickness, depth and mean water temperature were the top three important factors in affecting the distribution of D. mawsoni. The ensemble prediction suggests an overall expansion of fishable habitats, potentially due to the limited occurrence records from fishery-dependent surveys. Future projections indicate varying degrees of fishable habitat loss in large areas of the Amery Ice Shelf’s eastern and western portions. Suitable fishable habitats, including the spawning grounds in the seamounts around the northern Ross Sea and the coastal waters of the Bellingshausen Sea and Amundsen Sea, were persistent under present and future environmental conditions, highlighting the importance to protect these climate refugia from anthropogenic disturbance. Though data deficiency existed in this study, our predictions can provide valuable information for designing climate-adaptive development and conservation strategies in maintaining the sustainability of this species.
An adaptive data-driven architecture for mental health care applications
Authors: Sundaram Aishwarya , Subramaniam Hema , Ab Hamid Siti Hafizah , Mohamad Nor Azmawaty
Published: March 2024

Background

In the current era of rapid technological innovation, our lives are becoming more closely intertwined with digital systems. Consequently, every human action generates a valuable repository of digital data. In this context, data-driven architectures are pivotal for organizing, manipulating, and presenting data to facilitate positive computing through ensemble machine learning models. Moreover, the COVID-19 pandemic underscored a substantial need for a flexible mental health care architecture. This architecture, inclusive of machine learning predictive models, has the potential to benefit a larger population by identifying individuals at a heightened risk of developing various mental disorders.

Objective

Therefore, this research aims to create a flexible mental health care architecture that leverages data-driven methodologies and ensemble machine learning models. The objective is to proficiently structure, process, and present data for positive computing. The adaptive data-driven architecture facilitates customized interventions for diverse mental disorders, fostering positive computing. Consequently, improved mental health care outcomes and enhanced accessibility for individuals with varied mental health conditions are anticipated.

Method

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, the researchers conducted a systematic literature review in databases indexed in Web of Science to identify the existing strengths and limitations of software architecture relevant to our adaptive design. The systematic review was registered in PROSPERO (CRD42023444661). Additionally, a mapping process was employed to derive essential paradigms serving as the foundation for the research architectural design. To validate the architecture based on its features, professional experts utilized a Likert scale.

Results

Through the review, the authors identified six fundamental paradigms crucial for designing architecture. Leveraging these paradigms, the authors crafted an adaptive data-driven architecture, subsequently validated by professional experts. The validation resulted in a mean score exceeding four for each evaluated feature, confirming the architecture’s effectiveness. To further assess the architecture’s practical application, a prototype architecture for predicting pandemic anxiety was developed.
Transcranial magnetic stimulation enhances the specificity of multiple sclerosis diagnostic criteria: a critical narrative review
Authors: Snow Nicholas J. , Murphy Hannah M. , Chaves Arthur R. , Moore Craig S. , Ploughman Michelle
Published: March 2024

Background

Multiple sclerosis (MS) is an immune-mediated neurodegenerative disease that involves attacks of inflammatory demyelination and axonal damage, with variable but continuous disability accumulation. Transcranial magnetic stimulation (TMS) is a noninvasive method to characterize conduction loss and axonal damage in the corticospinal tract. TMS as a technique provides indices of corticospinal tract function that may serve as putative MS biomarkers. To date, no reviews have directly addressed the diagnostic performance of TMS in MS. The authors aimed to conduct a critical narrative review on the diagnostic performance of TMS in MS.

Methods

The authors searched the Embase, PubMed, Scopus, and Web of Science databases for studies that reported the sensitivity and/or specificity of any reported TMS technique compared to established clinical MS diagnostic criteria. Studies were summarized and critically appraised for their quality and validity.

Results

Seventeen of 1,073 records were included for data extraction and critical appraisal. Markers of demyelination and axonal damage—most notably, central motor conduction time (CMCT)—were specific, but not sensitive, for MS. Thirteen (76%), two (12%), and two (12%) studies exhibited high, unclear, and low risk of bias, respectively. No study demonstrated validity for TMS techniques as diagnostic biomarkers in MS.

Conclusions

CMCT has the potential to: (1) enhance the specificity of clinical MS diagnostic criteria by “ruling in” true-positives, or (2) revise a diagnosis from relapsing to progressive forms of MS. However, there is presently insufficient high-quality evidence to recommend any TMS technique in the diagnostic algorithm for MS.
Identification, validation and quantification of thymoquinone in conjunction with assessment of bioactive possessions and GC-MS profiling of pharmaceutically valuable crop Nigella (Nigella sativa L.) varieties
Authors: Y Ravi , Periyanadar Irene Vethamoni , Saxena Shailendra Nath , Muthurajan Raveendran , Sundararajan Velmurugan , Pridiuldi Santhanakrishnan Vichangal , Meena Sumer Singh , Naik Ashoka Narayana , Harisha C. B. , Asangi Honnappa , Choudhary Sharda , Singh Ravindra , Dengeru Yallappa , V Kavan Kumar , Meena Narottam Kumar , Meena Ram Swaroop , Verma Arvind Kumar
Published: March 2024

Background

Plants have been pivotal in traditional and modern medicine globally, with historical evidence supporting their therapeutic applications. Nigella (Nigella sativa L.) is an annual herbaceous plant of the Ranunculaceae family and is cultivated in the Middle East, Eastern Europe, and Western and Central Asia. The medicinal use of plants dates back thousands of years, documented in ancient writings from various civilizations. Alkaloids, phenolics, saponins, flavonoids, terpenoids, anthraquinones, and tannins found in plants exhibit antioxidant, immunomodulatory, anti-inflammatory, anticancer, antibacterial, and antidiabetic activities.

Methodology

This study specifically examines the pharmacological potential of Nigella sativa L., emphasizing thymoquinone—a compound with diverse nutraceutical benefits. The extraction, characterization, and quantification of thymoquinone, alongside other physicochemical parameters, were carried out using ethanol through Soxhlet extraction procedures on five nigella varieties. HPLC analysis was performed to determine the maximum accumulation of thymoquinone in the released variety of the plant and the chemical composition of the seed oil isolated from Nigella sativa L., varieties utilized in the study was determined through GC-MS analysis.

Results

The research revealed that the Ajmer nigella-20 variety stands out, exhibiting elevated levels of thymoquinone (0.20 ± 0.07%), antioxidants (76.18 ± 1.78%), and substantial quantities of total phenols (31.85 ± 0.97 mg GAEg−1 seed) and flavonoids (8.150 ± 0.360 mg QE 100 g−1 seed) compared to other varieties. The GC-MS profiling showed the presence of 11 major compounds in the studied varieties, with p-cymene, longifolene, and myristic acid identified as the major chemical compounds present in the oil.

Conclusion

The observed variations among Nigella varieties indicate the Ajmer nigella-20 variety as particularly promising for thymoquinone and bioactive compound extraction. This study underscores Nigella’s potential as a source of pharmacologically active compounds, highlighting the need for further exploration in therapeutic applications.
How tapeworms interact with cancers: a mini-review
Authors: Schreiber Manfred , Vajs Vojtěch , Horák Petr
Published: March 2024

Cancer is one of the leading causes of death, with an estimated 19.3 million new cases and 10 million deaths worldwide in 2020 alone. Approximately 2.2 million cancer cases are attributed to infectious diseases, according to the World Health Organization (WHO). Despite the apparent involvement of some parasitic helminths (especially trematodes) in cancer induction, there are also records of the potential suppressive effects of helminth infections on cancer. Tapeworms such as Echinococcus granulosus, Taenia crassiceps, and more seem to have the potential to suppress malignant cell development, although in a few cases the evidence might be contradictory. Our review aims to summarize known epidemiological data on the cancer-helminth co-occurrence in the human population and the interactions of tapeworms with cancers, i.e., proven or hypothetical effects of tapeworms and their products on cancer cells in vivo (i.e., in experimental animals) or in vitro. The prospect of bioactive tapeworm molecules helping reduce the growth and metastasis of cancer is within the realm of future possibility, although extensive research is yet required due to certain concerns.
Assessment of Knowledge and Compliance with Hand Hygiene among Health Personnel to Reduce Methicillin Resistant Staphylococcus aureus Nosocomial Infections: A Prospective Observational Study from a Tertiary Care Hospital in Southern India
Authors: Swathi Kalangari , Kandasamy SankaraRaman , Sangamithra V , Shankar Kandasamy Chitresh , Kushbu Dudekula
Published: March 2024

Introduction: Following a significant recovery from Coronavirus Disease-2019 (COVID-19) pandemic, the world has recognised that Hand Hygiene (HH) and facial masks are key preventive measures against various cross infections, particularly in hospital settings. Studying the incidence of Methicillin Resistant Staphylococcus aureus (MRSA) as a part of Healthcare Associated Infections (HAI) surveillance is crucial, as MRSA transmission can be effectively prevented through HH. Aim: To assess the knowledge and compliance of HH among health personnel using the World Health Organisation (WHO) HH questionnaire. Materials and Methods: A prospective observational study was conducted at Bhaarath Medical College and Hospital, Chennai, Tamil Nadu, India, over one year, from December 2020 to November 2021. The Hospital Infection Control Committee (HICC) team carried out an HH survey using the WHO HH questionnaire to evaluate knowledge and attitudes among 115 Healthcare Workers (HCWs), including doctors and nursing staff, in a tertiary care hospital in Kanchipuram, Southern India. The study also involved monitoring monthly MRSA incidence density rates in Intensive Care Unit (ICU) settings as part of HAI surveillance, followed by regular HH audits. MRSA infectivity rates were statistically analysed using paired t-tests with Statistical Package for Social Sciences (SPSS) software version 21.0 to determine p-values and address standard deviations. Results: In this study, 26 (65%) of doctors had undergone training, while 57 (76%) of nurses reported recent formal HH training. Only 16 (40%) of doctors and 21 (28%) of nurses used alcohol-based handrub. Doctors exhibited knowledge ranging from 60-77.5% on germ transmission and hand rub-related questions, while nurses demonstrated better knowledge ranging from 72-93.3%. HH adherence was 30% among doctors and 72% among nurses. The MRSA infectivity rate varied over the year, starting at 1.33 per 1000 resident days before HH audits and decreasing to 0.3. Each HH audit led to a significant improvement in MRSA rates, with a p-value <0.0001, indicating statistical significance. Conclusion: Present study evaluated HCWs knowledge and attitudes toward HH, along with the impact of HH audits on reducing MRSA rates, has proven to be beneficial for hospital infection control practices, particularly during the COVID-19 pandemic and its aftermath, when vigilance tends to decrease over time.
Health of women deprived of freedom: concepts of workers and health professionals in a criminal unit / Saúde de mulheres privadas de liberdade: concepções de trabalhadores e profissionais de saúde em unidade penal
Authors: Anversa Elenir Terezinha Rizzetti , Farias Alves Lidiane , Donaduzzi Daiany Saldanha da Silveira , Flores Gisela Cataldi
Published: March 2024

Objetivo: compreender como os trabalhadores e profissionais de saúde de uma unidade penal efetivam o cuidado de mulheres privadas de liberdade. Método: estudo qualitativo descritivo exploratório, realizado em uma unidade penal da Região Central do Rio Grande do Sul. A coleta de dados foi realizada por meio de entrevista semiestruturada. A Análise dos dados utilizado foi o referencial teórico de Bardin. Resultados: construída duas categorias: A invisibilidade das Mulheres Privadas de Liberdade: nas Redes de Atenção à Saúde e o cuidado as mulheres privadas de liberdade: a dor do isolamento, da solidão e da fragilidade no processo saúde doença. Considerações finais: a Atenção à Saúde dentro da unidade penal é fragmentada, necessitando de organização, comunicação efetiva e horizontalidade para a melhoria do cuidado, bem como, a necessidade do fortalecimento da rede de apoio e cuidados em relação ao gênero.
Spiritual/religious support for nursing in the treatment of breast cancer: integrative review / Aporte espiritual/religioso pela enfermagem no tratamento do câncer de mama: revisão integrativa
Authors: De Paula Silva Cremilson , Paula Alonso Reis Ana
Published: March 2024

Objetivo: analisar na literatura científica a importância da abordagem espiritual/religiosa pela equipe de enfermagem no tratamento do câncer de mama. Método: revisão integrativa, realizada na BDENF, LILACS e SCOPUS. Resultados: foram selecionados seis estudos, evidenciou-se que a abordagem espiritual/religiosa pelos profissionais de enfermagem auxilia para o enfrentamento positivo do câncer de mama. Assim, emergiu a categoria: Abordagem espiritual/religiosa na assistência de enfermagem e suas repercussões positivas para o enfrentamento do câncer de mama. Conclusão: a categoria da enfermagem integra a rede de apoio social para o alívio do sofrimento, por meio do aporte espiritual/religioso, auxiliando para a minimização de sentimentos negativos associados ao diagnóstico e aos eventos adversos dos tratamentos, sendo importante incluir discussões acerca desta temática na formação de nível técnico e graduação em enfermagem.
Self-care and lifestyle habits of nursing students during the Sars-Cov-2 pandemic / Autocuidado e hábitos de vida de acadêmicos de enfermagem durante a pandemia de Sars-Cov-2
Authors: Logullo Vitória Vasconcelos , Lino Iven Giovanna Trindade , Balestre Mariana Enumo , Gomes Beatriz Jorge Oliveira , Ramos Sabrina Rodrigues , Marcon Sonia Silva
Published: March 2024

Objetivo: compreender de que maneira a pandemia de Covid-19 interferiu no autocuidado e estilo de vida de universitários. Método: pesquisa descritiva exploratória realizada com acadêmicos de enfermagem de quatro instituições de ensino superior do estado do Paraná. Os dados foram coletados mediante formulário eletrônico disponibilizado no google forms; os de natureza quantitativa foram submetidos à análise descritiva e inferencial, e as respostas às questões abertas analisadas no Software Iramuteq. Resultados: participaram do estudo 58 estudantes de enfermagem, sendo a maioria do sexo feminino (82,76%), com idade média de 22 anos, a maioria residia com sua família. Observada associação estatisticamente significativa entre Idade e “Fez amizade durante aulas remotas”; Sexo e “uso de substância’’; e Ano da graduação com hábito alimentar e “Fez amizade durante aulas remotas”. Conclusão: a pandemia influenciou, especialmente, os hábitos alimentares, de autocuidado, qualidade do sono e uso álcool e tabaco entre os acadêmicos de enfermagem.
Microwave‐Assisted Asymmetric Intermolecular Heck Reaction using Phosphine‐Thiazole Ligands
Authors: Kaukoranta Päivi , Källström Klas , Andersson Pher G.
Published: November 2007

A series of new phosphine‐thiazole compounds has been synthesized and used as efficient ligands in the palladium‐catalyzed asymmetric intermolecular Heck coupling of 2,3‐dihydrofuran with aryl triflates and cyclohexenyl triflate. Microwave heating was used to accelerate the reactions and gave complete conversions in as little as one hour. Products were obtained with good to excellent enantioselectivities.
In vitro release of salicylic acid through poly(vinyl alcohol‐g‐itaconic acid) membranes
Authors: Asman Gülsen , Şanlı Oya , Tuncel Didem
Published: November 2007

In this study, itaconic acid (IA) was grafted on poly(vinyl alcohol) (PVA) at two different grafting percentages, 7.0% (w/w) and 14.0% (w/w), and membranes were prepared from the grafted copolymer (PVA‐g‐IA). Performances of PVA and PVA‐g‐IA membranes for the transdermal release of salicylic acid (SA) at in vitro conditions were investigated by using 2.0 mg/mL SA solutions. Effect of the pH on the release of SA was studied by keeping pH of donor and acceptor solutions in a range of (2.1–7.4). Permeation studies were also carried on at different SA concentrations. Effect of temperature on the release of SA was investigated in the temperature range of (32–39) (±1)°C. Results showed that presence of IA decreased the release of SA from the PVA membranes and 73% SA was released at the end of 48 h at (32 ± 1)°C from the IA‐1 membranes. pH affected the release of SA through the grafted membranes and studies showed that release of SA was high with donor solution pH of 2.1. When the pH of donor and receiver solutions were kept at the same pH value, the overall SA% in permeate increased. Increase in concentration of SA decreased the release of SA for the studied membranes. Release of SA from PVA‐g‐IA membranes was temperature sensitive and increase in temperature from (32 ± 1)°C to (39 ± 1)°C increased the release percentage of SA by 24% (w/w). The overall activation energy for the permeation of SA through IA‐1 membrane was found to be 22.97 kJ/mol. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Ca2+ responses to thyrotropin‐releasing hormone and angiotensin II: the role of plasma membrane integrity and effect of G11α protein overexpression on homologous and heterologous desensitization
Authors: Ostasov Pavel , Krusek Jan , Durchankova Dana , Svoboda Petr , Novotny Jiri
Published: November 2007

The molecular mechanisms involved in GPCR‐initiated signaling cascades where the two receptors share the same signaling cascade, such as thyrotropin‐releasing hormone (TRH) and angiotensin II (ANG II), are still far from being understood. Here, we analyzed hormone‐induced Ca2+ responses and the process of desensitization in HEK‐293 cells, which express endogenous ANG II receptors. These cells were transfected to express exogenously high levels of TRH receptors (clone E2) or both TRH receptors and G11α protein (clone E2M11). We observed that the characteristics of the Ca2+ response, as well as the process of desensitization, were both strongly dependent on receptor number and G11α protein level. Whereas treatment of E2 cells with TRH or ANG II led to significant desensitization of the Ca2+ response to subsequent addition of either hormone, the response was not desensitized in E2M11 cells expressing high levels of G11α. In addition, stimulation of both cell lines with THR elicited a clear heterologous desensitization to subsequent stimulation with ANG II. On the other hand, ANG II did not affect a subsequent response to TRH. ANG II‐mediated signal transduction was strongly dependent on plasma membrane integrity modified by cholesterol depletion, but signaling through TRH receptors was altered only slightly under these conditions. It may be concluded that the level of expression of G‐protein‐coupled receptors and their cognate G‐proteins strongly influences not only the magnitude of the Ca2+ response but also the process of desensitization and resistance to subsequent hormone addition. Copyright © 2007 John Wiley & Sons, Ltd.
XML Metadata Services
Authors: Aktas Mehmet S. , Fox Geoffrey C. , Pierce Marlon , Oh Sangyoon
Published: November 2007

As service‐oriented architecture principles have gained importance, an emerging need has appeared for methodologies to locate desired services that provide access to their capability descriptions. These services must typically be assembled into short‐term service collections that, together with code execution services, are combined into a meta‐application to perform a particular task. To address the metadata requirements of these problems, we introduce a hybrid Information Service to manage both stateless and stateful (transient) metadata. We leverage the two widely used Web Service standards: Universal Description, Discovery and Integration (UDDI) and Web Services Context (WS‐Context), in our design. We describe our approach and experiences when designing ‘semantics’. We report the results from a prototype of the system that is applied to a mobile environment for optimizing Web Service communications. Copyright © 2007 John Wiley & Sons, Ltd.
Different Reactivity Patterns in the Reactions of the Homologous Trimethylelement Compounds EMe3 (E = Al, Ga, In) with Methylhydrazine
Authors: Uhl Werner , Abel Thomas , Hepp Alexander , Grimme Stefan , Steinmetz Marc
Published: November 2007

The trimethylelement compounds EMe3 (E = Al, Ga, In) followed three different reaction courses upon treatment with methylhydrazine, H2N–N(H)Me. AlMe3 reacted at room temperature by releasing 1.5 equiv. methane to yield the sesquihydrazide (Me2Al)3[μ‐NH–N(H)Me]6Al (1), which in the solid state has a hexacoordinate central aluminum atom and six hydrazido groups in the bridging positions to the three terminally arranged AlMe2 groups. Dissociation occurred upon dissolution, and the dialuminum compound Me2Al[μ‐NH–N(H)Me]2Al(Me)[NH–N(H)Me] (2), containing one terminal hydrazido group, was identified unambiguously by NMR spectroscopy. GaMe3 gave a simple adduct, Me3Ga←N(H)Me–NH2 (3), under the same reaction conditions. Boiling toluene was required to initiate a secondary reaction with the release of methane. A bicyclic tetragallium compound, 4, in which a twofold deprotonated hydrazide, [HN–NMe]2–, bridges four gallium atoms, was the result. Each pair of gallium atoms on both sides of the central hydrazinediide ligand is further bridged by the monoanionic hydrazide [HN–N(H)Me]– to yield two annelated, five‐membered Ga2N3 heterocycles. A similar compound, 5, was directly obtained from the reaction of InMe3 with methylhydrazine at room temperature.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Breaking Infinite CuI Carboxylate Helix Held by Cuprophilicity into Discrete Cun Fragments (n = 6, 4, 2)
Authors: Sevryugina Yulia , Petrukhina Marina A.
Published: November 2007

A new copper(I) carboxylate complex with 3,5‐bis(trifluoromethyl)benzoate ligands, [Cu(O2C(3,5‐CF3)2C6H3)] (1), has been prepared in high yield and fully characterized. An X‐ray diffraction study revealed a remarkable infinite double‐helical chain motif held together by cuprophilic interactions ranging from 2.69 to 3.14 Å. Both left‐ and right‐handed helices are present in the unit cell of the centrosymmetric structure of 1 thus making the crystalline compound racemic. Complex 1 shows bright emission at ca. 594 nm upon UV/Vis radiation in the solid state (λex = 350 nm). The Cu···Cu contacts in 1 are easily broken in the gas phase to afford copper clusters of ascertained nuclearity upon sublimation with various polyaromatic hydrocarbons. Several polyarenes such as fluoranthene (C16H10), pyrene (C16H10), and coronene (C24H12) were selected to cover a broad temperature range from 130 to 220 °C for the gas‐phase co‐deposition reactions. As a result of the successive temperature increase, cleavage of the infinite copper(I) chain into [Cun(O2C(3,5‐CF3)2C6H3)n] fragments of decreasing nuclearity, n = 6, 4, and 2, has been achieved. The isolation of these units represents the first instance where various polynuclear copper(I) complexes are prepared and structurally characterized for the same carboxylate ligand.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Sensitivity analysis of low Reynolds number channel flow using the finite volume method
Authors: Kirkman R. D. , Metzger M.
Published: November 2007

An unsteady finite volume‐based fractional step algorithm solved on a staggered grid has been developed for computing design sensitivity parameters in two‐dimensional flows. Verification of the numerical code is performed for the case of low Reynolds number, pressure‐driven flow through a straight channel, which has an exact steady‐state solution to the Navier–Stokes equations. Sensitivity of the flow to the channel height, fluid viscosity, and imposed pressure gradient is considered. Three different numerical techniques for computing the design sensitivity parameters: finite difference, complex‐step differentiation, and sensitivity equation method (SEM), are compared in terms of numerical error (relative to the exact solution), computational expense, and ease of implementation. Results indicate that, of all the three methods, complex step is the most accurate and requires the least computational time. In addition, treatment of the boundary conditions in SEM is addressed, within the framework of the present finite volume approach, with special attention given to parameter dependence in the boundary conditions. Error estimation based on the Grid Convergence Index provides a good indication of the exact error in the SEM solutions. An example of application of the use of sensitivity parameters to estimate the propagation of input uncertainty through the numerical simulation is also provided. Copyright © 2007 John Wiley & Sons, Ltd.
Interference effect of two equal‐sized square cylinders in tandem arrangement: With planar shear flow
Authors: Lankadasu A. , Vengadesan S.
Published: November 2007

Numerical simulations have been performed for flow past two equal‐sized square cylinders in tandem arrangement subjected to incoming planar shear flow. Effect of L/d ratio and the shear parameter has been studied. The range of L/d ratio (ratio of center‐to‐center distance (L) to cylinder width (d)) is varied from 2 to 7 and the non‐dimensional shear parameter (K) is varied from 0.0 to 0.4 in steps of 0.1. For all the cases the Reynolds number (Re) based on centerline velocity and cylinder width is fixed at 100. The results are compared with that of isolated square cylinder with uniform flow. Strouhal number decreases with increasing shear parameter. There are more than one shedding frequency at high shear parameters and L/d ratios. The mean drag coefficient is decreased with shear parameter and lesser than that of the single cylinder. The root mean square (RMS) value of both lift and drag coefficients is higher for the downstream cylinder for all values of shear parameter. With increasing L/d ratio, for both lift and drag, the RMS value increases and then decreases for upstream cylinder, whereas it continuously increases for the downstream cylinder. The stagnation point is moved towards the top leading edge with increasing shear. The critical L/d ratio, which is defined as the distance between two cylinders, beyond which the vortex shedding from the upstream cylinder occurs, decreases with increasing shear parameter. Copyright © 2007 John Wiley & Sons, Ltd.
The peroxisome proliferator‐activated receptor‐γ agonist 1,1‐bis(3′‐indolyl)‐1‐(p‐trifluoromethylphenyl)methane suppresses manganese‐induced production of nitric oxide in astrocytes and inhibits apoptosis in cocultured PC12 cells
Authors: Tjalkens Ronald B. , Liu Xuhong , Mohl Brianne , Wright Tyler , Moreno Julie A. , Carbone David L. , Safe Stephen
Published: November 2007

Reactive astrogliosis is a prominent neuropathologic feature of manganism, a neurodegenerative disorder caused by excessive accumulation of manganese (Mn) in the basal ganglia. Activation of astrocytes has been linked to neuronal injury in manganism resulting from overproduction of inflammatory mediators, including tumor necrosis factor‐α (TNFα), interferon‐γ (IFNγ), interleukin‐1β (IL‐1β), and nitric oxide (NO), but the signaling mechanisms by which Mn regulates these factors remain poorly understood. We previously reported that Mn enhances production of NO in activated astrocytes that promotes apoptosis in cocultured neuronal cells by a mechanism involving the transcription factor nuclear factor‐κB (NF‐κB) (Liu et al., 2005). Because NF‐κB‐dependent expression of inducible nitric oxide synthase (NOS2) can be antagonized by the nuclear orphan receptor peroxisome proliferator‐activated receptor‐γ (PPARγ), we postulated that a novel agonist of this receptor, 1,1‐bis(3′‐indolyl)‐1‐(p‐trifluoromethylphenyl)methane (cDIM1), would suppress expression of NOS2 in astrocytes and protect cocultured neuronal cells from apoptosis. Submicromolar concentrations of cDIM1 potently suppressed production of NO and expression of NOS2 in cultured astrocytes exposed to Mn and IFNγ/TNFα and prevented apoptosis in cocultures of differentiated PC12 cells, but this neuroprotective effect was lost in the absence of astrocytes. By using fluorescence reporter and chromatin immunoprecipitation (ChIP) assays, we found that cDIM1 prevented activation of NF‐κB in astrocytes by a mechanism involving stabilization of the nuclear corepressor 2 (NCoR2) on the proximal NF‐κB binding site of the NOS2 promoter. These data suggest that PPARγ may be an effective target for limiting inflammatory activation of astrocytes during neurologic injury. © 2007 Wiley‐Liss, Inc.
Fabrication of Poly(L‐lactide)‐block‐Poly(ethylene glycol)‐block‐Poly(L‐lactide) Triblock Copolymer Thin Films with Nanochannels: An AFM Study
Authors: Choi Sung‐Wook , Kim Yongwoo , Cheong In Woo , Kim Jung‐Hyun
Published: November 2007

This paper aims to report the fabrication of biodegradable thin films with micro‐domains of cylindrical nanochannels through the solvent‐induced microphase separation of poly(L‐lactide)‐block‐poly(ethylene glycol)‐block‐poly(L‐lactide) (PLA‐b‐PEG‐b‐PLA) triblock copolymers with different block ratios. In our experimental scope, an increase in each of the block lengths of the PLA and PEG blocks led to both a variation in the average number density (146 to 32 per 100 µm2) and the size of the micro‐domains (140 to 427 nm). Analyses by atomic force microscopy (AFM) and fluorescence microscopy indicated that the hydrophilic PEG nanochannels were dispersed in the PLA matrix of the PLA‐b‐PEG‐b‐PLA films. We demonstrated that the micro‐domain morphology could be controlled not only by the block length of PEG, but also by the solvent evaporation conditions.

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FGF‐1‐induced matrix metalloproteinase‐9 expression in breast cancer cells is mediated by increased activities of NF‐κB and activating protein‐1
Authors: Lungu Gina , Covaleda Lina , Mendes Odete , Martini‐Stoica Heidi , Stoica George
Published: November 2007

Matrix metalloproteinase‐9 (MMP‐9) plays a critical role in tumor invasion and metastasis. Here, we investigate the effect of fibroblast growth factor‐1 (FGF‐1) on the expression of MMP‐9 in ENU1564, an ethyl‐N‐nitrosourea‐induced rat mammary adenocarcinoma cell line. We observed that FGF‐1 induces a dose‐dependent increase in MMP‐9 mRNA, protein, and activity in ENU1564 cells. To gain insight into the molecular mechanism of MMP‐9 regulation by FGF‐1, we investigated the role of components of PI3K‐Akt and MEK1/2‐ERK signaling pathways in our system since NF‐κB and AP‐1 transcription factor binding sites have been characterized in the upstream region of the MMP‐9 gene. We demonstrated that FGF‐1 increases Akt phosphorylation, triggers nuclear translocation of NF‐κBp65, and enhances degradation of cytoplasmic IκBα. Pretreatment of cells with LY294002, a PI3K inhibitor, significantly inhibited MMP‐9 protein expression in FGF‐1‐treated cells. Conversely, our data show that FGF‐1 increases ERK phosphorylation in ENU1564 cells, increases c‐jun and c‐fos mRNA expression in a time‐dependent manner, and triggers nuclear translocation of c‐jun. Pretreatment of cells with PD98059, a MEK1/2 inhibitor significantly inhibited MMP‐9 protein expression in FGF‐1 treated cells. Finally, we observed increased DNA binding of NF‐κB and AP‐1 in FGF‐1‐treated cells and that mutation of either NF‐κB or AP‐1 response elements prevented MMP‐9 promoter activation by FGF‐1. Taken together, these results demonstrated that FGF‐1‐induced MMP‐9 expression in ENU1564 cells is associated with increasing DNA binding activities of NF‐κB and AP‐1 and involve activation of a dual signaling pathway, PI3K‐Akt and MEK1/2‐ERK. © 2007 Wiley‐Liss, Inc.
Woody debris stocks in different secondary and primary forests in the subtropical Ailao Mountains, southwest China
Authors: Lipan Yang , Wenyao Liu , Wenzhang Ma
Published: November 2007

Woody debris (WD), including coarse woody debris (CWD) and fine woody debris (FWD), is an essential structural and functional component of many ecosystems, particularly in montane forests. CWD is considered to be the major part in forest WD and it is primarily composed of logs, snags, stumps and large branches, while FWD mainly consists of small twigs. Attributes of dead woody material may change in accordance with trends in stand dynamics. The primary forest (primary montane moist evergreen broad‐leaved forest) in Ailao Mountain National Nature Reserve (NNR) preserves the largest tract of natural vegetation in China. The Alnus nepalensis (D. Don) association, Populus bonatii (Levl.) association and secondary Lithocarpus association represent the secondary and chronological types following human disturbance by fires and logging under different intensity. The mass and composition of coarse woody debris (CWD, ≥10 cm in diameter) and fine woody debris (FWD, 2.5–10 cm in diameter) were inventoried in a primary forest and its three secondary counterparts. Estimates of total mass of woody debris across secondary types to primary forest ranged from 2.4 to 74.9 Mg ha−1. The lowest value was found in the A. nepalensis association and the highest values were in the primary forest of which logs are the considerable differences. The ratios of CWD to FWD were low in the secondary types (about 1–4) but high in the primary forest (above 15). Our results suggested that for the recovery of woody debris in the secondary forest, it might last longer than the age of the oldest successional stage studied.
PPARα‐dependent induction of the energy homeostasis‐regulating nuclear receptor NR1i3 (CAR) in rat hepatocytes: Potential role in starvation adaptation
Authors: Wieneke Nadine , Hirsch-Ernst Karen I. , Kuna Manuela , Kersten Sander , Püschel Gerhard P.
Published: November 2007

A tight hormonal control of energy homeostasis is of pivotal relevance for animals. Recent evidence suggests an involvement of the nuclear receptor NR1i3 (CAR). Fasting induces CAR by largely unknown mechanisms and CAR‐deficient mice are defective in fasting adaptation. In rat hepatocytes CAR was induced by WY14643, a PPARα‐agonist. A DR1 motif in the CAR promoter was necessary and sufficient for this control. The PPARα‐dependent increase in CAR potentiated the phenobarbital‐induced transcription of the prototypical CAR‐dependent gene CYP2B1. Since free fatty acids are natural ligands for PPARα, a fasting‐induced increase in free fatty acids might induce CAR. In accordance with this hypothesis, CAR induction by fasting was abrogated in PPARα‐deficient mice.
Histological and immunological features of non‐eosinophilic nasal polyps
Authors: Kim Jeong‐Whun , Hong Sung‐Lyong , Kim Yoon‐Keun , Lee Chul Hee , Min Yang‐Gi , Rhee Chae‐Seo
Published: November 2007

Objective

The aim of this study was to investigate the his‐toimmunological features of non‐eosinophilic nasal polyps (NPs).

METHODS

Thirty patients with chronic rhinosinusitis and NPs were included in this study. NPs were grouped into eosinophilic and non‐eosinophilic types according to the amount of eosinophils in the NPs. The amount of serum total IgE and peripheral blood eosinophils were measured. Basement membrane (BM) thickness was measured, along with the expression of chemokine receptor 5 (CCR5) and chemokine receptor 3 (CCR3) in NP lymphocytes.

RESULTS

Non‐eosinophilic NPs comprised 66.7% of the total NPs included in this study. The amount of eosinophils in NPs was related to eosinophilia of the peripheral blood, but not to elevated serum IgE. BM was significantly thinner in non‐eosinophilic than in eosinophilic NPs. Lymphocytes expressing CCR5 or CCR3 were less frequently found in non‐eosinophilic than in eosinophilic NPs.

CONCLUSION

Histoimmunological characteristics of non‐eo‐sinophilic NPs differ from those of eosinophilic NPs; non‐eosino‐philic NPs may be featured by thinner BM and fewer CCR5‐ and CCR3‐positive lymphocytes.
Quantitative and qualitative dermal change with microfat grafting of facial scars
Authors: Sardesai Maya G. , Moore Corey C.
Published: November 2007

Objective

To evaluate changes in dermal characteristics with subdermal fat grafting of cutaneous scars.

DESIGN

Prospective cohort.

METHODS

Fourteen patients with various scar types were treated with subdermal fat grafting over 30 months. Dermal elasticity, vascularity, pigmentation, patient perception and satisfaction, and observer assessment of scar characteristics were evaluated preoperatively and 1 year after treatment with validated objective and subjective measures.

RESULTS

Significant improvements were observed in dermal elasticity, patient and observer perception of scar thickness, patient perception of stiffness, and observer perception of relief and pliability (P < 0.05). A trend toward significance was seen in observer assessment of height as evaluated by the Vancouver Scar Scale (P < 0.1). No significant differences were seen in quantitatively and qualitatively measured vascularity and pigmentation (P > 0.1). No significant difference in pain, pruritis, and irregularity were reported (P > 0.1).

CONCLUSION

Although fat grafting represents a subdermal process, it appears to improve certain quantitative and qualitative dermal characteristics. Fat grafting does not appear to affect skin color, vascularity, or patient symptoms.