bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differential pH-dependent cellular uptake pathways among foamy viruses elucidated using dual-colored fluorescent particles
Authors: Stirnnagel Kristin , Schupp Dorothee , Dupont Aurélie , Kudryavtsev Volodymyr , Reh Juliane , Müllers Erik , Lamb Don C , Lindemann Dirk 
Published: August 2012

Abstract

Background
It is thought that foamy viruses (FVs) enter host cells via endocytosis because all FV glycoproteins examined display pH-dependent fusion activities. Only the prototype FV (PFV) glycoprotein has also significant fusion activity at neutral pH, suggesting that its uptake mechanism may deviate from other FVs. To gain new insights into the uptake processes of FV in individual live host cells, we developed fluorescently labeled infectious FVs.

Results
N-terminal tagging of the FV envelope leader peptide domain with a fluorescent protein resulted in efficient incorporation of the fluorescently labeled glycoprotein into secreted virions without interfering with their infectivity. Double-tagged viruses consisting of an eGFP-tagged PFV capsid (Gag-eGFP) and mCherry-tagged Env (Ch-Env) from either PFV or macaque simian FV (SFVmac) were observed during early stages of the infection pathway. PFV Env, but not SFVmac Env, containing particles induced strong syncytia formation on target cells. Both virus types showed trafficking of double-tagged virions towards the cell center. Upon fusion and subsequent capsid release into the cytosol, accumulation of naked capsid proteins was observed within four hours in the perinuclear region, presumably representing the centrosomes. Interestingly, virions harboring fusion-defective glycoproteins still promoted virus attachment and uptake, but failed to show syncytia formation and perinuclear capsid accumulation. Biochemical and initial imaging analysis indicated that productive fusion events occur predominantly within 4–6 h after virus attachment. Non-fused or non-fusogenic viruses are rapidly cleared from the cells by putative lysosomal degradation. Quantitative monitoring of the fraction of individual viruses containing both Env and capsid signals as a function of time demonstrated that PFV virions fused within the first few minutes, whereas fusion of SFVmac virions was less pronounced and observed over the entire 90 minutes measured.

Conclusions
The characterized double-labeled FVs described here provide new mechanistic insights into FV early entry steps, demonstrating that productive viral fusion occurs early after target cell attachment and uptake. The analysis highlights apparent differences in the uptake pathways of individual FV species. Furthermore, the infectious double-labeled FVs promise to provide important tools for future detailed analyses on individual FV fusion events in real time using advanced imaging techniques.
Anaplasma phagocytophilum in horses and ticks in Tunisia
Authors: M’ghirbi Youmna , Yaïch Hèla , Ghorbel Abderazek , Bouattour Ali 
Published: August 2012

AbstractBackgroundAnaplasma phagocytophilum, the causative agent of granulocytic anaplasmosis, affects several species of wild and domesticated mammals, including horses. We used direct and indirect methods to compare and evaluate exposure toA. phagocytophilumin horses in northern Tunisia.MethodsSerum from 60 horses was tested by IFA for antibodies toA. phagocytophilum, and whole blood was tested forA. phagocytophilum16S rRNA gene using a nested-PCR. To examine the risk ofA. phagocytophilumtransmission, 154 ticks that had been collected from horses were examined for the presence ofA. phagocytophilumby nested-PCR targeting 16S rRNA gene.ResultsThis is the first time thatA. phagocytophilumhas been detected in horses in Tunisia, with an overall seroprevalence of 40/60 (67%). Six of the seroreactive samples (10%) had an IFA titer of 1:80, 14 (23%) of 1:160, 8 (13%) of 1:320 and 12 (20%) a titer 1 ≥ 640. The seroprevalence revealed no significant regional and sex differences. In contrast, a significant difference was observed between breeds. Eight (13%) of the horses were positive forA. phagocytophilumin the PCR, with no significant breed and age differences.Hyalomma marginatumwas a predominant tick species (130/154),and 3 were infected byA. phagocytophilum(a prevalence of 2.3%). The concordance rate ofA. phagocytophilumdetection between IFA and PCR had akvalue of −0.07.ConclusionsThe results presented in this study suggest that horses infested by ticks in Tunisia are exposed toA. phagocytophilum.
Gene expression profile suggests that pigs (Sus scrofa) are susceptible to Anaplasma phagocytophilum but control infection
Authors: Galindo Ruth C , Ayllón Nieves , Smrdel Katja Strašek , Boadella Mariana , Beltrán-Beck Beatriz , Mazariegos María , García Nerea , de la Lastra José M Pérez , Avsic-Zupanc Tatjana , Kocan Katherine M , Gortazar Christian , de la Fuente José 
Published: August 2012

AbstractBackgroundAnaplasma phagocytophiluminfects a wide variety of hosts and causes granulocytic anaplasmosis in humans, horses and dogs and tick-borne fever in ruminants. Infection withA. phagocytophilumresults in the modification of host gene expression and immune response. The objective of this research was to characterize gene expression in pigs (Sus scrofa) naturally and experimentally infected withA. phagocytophilumtrying to identify mechanisms that help to explain low infection prevalence in this species.ResultsFor gene expression analysis in naturally infected pigs, microarray hybridization was used. The expression of differentially expressed immune response genes was analyzed by real-time RT-PCR in naturally and experimentally infected pigs. Results suggested thatA. phagocytophiluminfection affected cytoskeleton rearrangement and increased both innate and adaptive immune responses by up regulation of interleukin 1 receptor accessory protein-like 1 (IL1RAPL1), T-cell receptor alpha chain (TCR-alpha), thrombospondin 4 (TSP-4) and Gap junction protein alpha 1 (GJA1) genes. Higher serum levels of IL-1 beta, IL-8 and TNF-alpha in infected pigs when compared to controls supported data obtained at the mRNA level.ConclusionsThese results suggested that pigs are susceptible toA. phagocytophilumbut control infection, particularly through activation of innate immune responses, phagocytosis and autophagy. This fact may account for the low infection prevalence detected in pigs in some regions and thus their low or no impact as a reservoir host for this pathogen. These results advanced our understanding of the molecular mechanisms at the host-pathogen interface and suggested a role for newly reported genes in the protection of pigs againstA. phagocytophilum.
Synthesis and antibacterial activity of novel levofloxacin derivatives containing a substituted thienylethyl moiety
Authors: Mohammadhosseini Negar , Alipanahi Zahra , Alipour Eskandar , Emami Saeed , Faramarzi Mohammad Ali , Samadi Nasrin , Khoshnevis Nika , Shafiee Abbass , Foroumadi Alireza 
Published: August 2012

Abstract

Background and the purpose of the study
Piperazinyl quinolones such as ciprofloxacin, ofloxacin and levofloxacin are an important group of quinolone antimicrobials which are widely used in the treatment of various infectious diseases. In the present study, we synthesized a new series of levofloxacin derivatives and evaluated their antibacterial activities.

Methods
The N-substituted analogs of levofloxacin 6a–j were prepared by nucleophilic reaction of N-desmethyl levofloxacin 11 with thienylethyl bromide derivatives 8 or 9. All target compounds were tested using conventional agar dilution method in comparison to levofloxacin and N-desmethyl levofloxacin and their MIC values were determined against a panel of Gram-positive and Gram-negative bacteria.

Results
All compounds showed significant antibacterial activities against Gram-positive bacteria (MIC = 0.04-6.25 μg/mL); however, the activity against Gram-negative bacteria was lower (MIC = 1.56–100 μg/mL). As is evident from the data, oxime derivatives 6e, 6h and 6i are superior in inhibiting the growth of Gram-positive bacteria (MIC = 0.04–0.19 μg/mL), and their activities were found to be 5–25 times better than N-desmethyl levofloxacin 11 and equal or better than levofloxacin 4.

Conclusion
We have designed and synthesized novel quinolone derivatives bearing functionalized thienylethyl moiety on the piperazine ring of levofloxacin. The results of antibacterial screening against Gram-positive and Gram-negative bacteria revealed that the introduction of functionalized thienylethyl moiety on the piperazine ring of levofloxacin can improve the activity against Gram-positive bacteria. Gram-positive bacteria are responsible for a wide range of infectious diseases, and rising resistance in this group is causing increasing concern. Thus, this study introduces structural features of levofloxacin scaffold for development of new candidates in the field of anti-Gram positive chemotherapy
Altered sodium channel-protein associations in critical illness myopathy
Authors: Kraner Susan D , Novak Kevin R , Wang Qingbo , Peng Junmin , Rich Mark M 
Published: August 2012

Abstract

Background
During the acute phase of critical illness myopathy (CIM) there is inexcitability of skeletal muscle. In a rat model of CIM, muscle inexcitability is due to inactivation of sodium channels. A major contributor to this sodium channel inactivation is a hyperpolarized shift in the voltage dependence of sodium channel inactivation. The goal of the current study was to find a biochemical correlate of the hyperpolarized shift in sodium channel inactivation.

Methods
The rat model of CIM was generated by cutting the sciatic nerve and subsequent injections of dexamethasone for 7 days. Skeletal muscle membranes were prepared from gastrocnemius muscles, and purification and biochemical analyses carried out. Immunoprecipitations were performed with a pan-sodium channel antibody, and the resulting complexes probed in Western blots with various antibodies.

Results
We carried out analyses of sodium channel glycosylation, phosphorylation, and association with other proteins. Although there was some loss of channel glycosylation in the disease, as assessed by size analysis of glycosylated and de-glycosylated protein in control and CIM samples, previous work by other investigators suggest that such loss would most likely shift channel inactivation gating in a depolarizing direction; thus such loss was viewed as compensatory rather than causative of the disease. A phosphorylation site at serine 487 was identified on the NaV 1.4 sodium channel α subunit, but there was no clear evidence of altered phosphorylation in the disease. Co-immunoprecipitation experiments carried out with a pan-sodium channel antibody confirmed that the sodium channel was associated with proteins of the dystrophin associated protein complex (DAPC). This complex differed between control and CIM samples. Syntrophin, dystrophin, and plectin associated strongly with sodium channels in both control and disease conditions, while β-dystroglycan and neuronal nitric oxide synthase (nNOS) associated strongly with the sodium channel only in CIM. Recording of action potentials revealed that denervated muscle in mice lacking nNOS was more excitable than control denervated muscle.

Conclusion
Taken together, these data suggest that the conformation/protein association of the sodium channel complex differs in control and critical illness myopathy muscle membranes; and suggest that nitric oxide signaling plays a role in development of muscle inexcitability.
Control of Allergic Rhinitis and Asthma Test (CARAT) can be used to assess individual patients over time
Authors: Fonseca Joao A , Nogueira‐Silva Luis , Morais‐Almeida Mario , Sa‐Sousa Ana , Azevedo Luis F , Ferreira Jose , Branco‐Ferreira Manuel , Rodrigues‐Alves Rodrigo , Bugalho‐Almeida Antonio , Bousquet Jean 
Published: August 2012

AbstractBackgroundThe Control of Allergic Rhinitis and Asthma Test (CARAT10) has been proposed as the first tool to implement the Allergic Rhinitis and its Impact on Asthma initiative guidelines in clinical practice. To serve this purpose, it must have adequate properties to assess the control of an individual over time. This study aimed to prospectively assess the test‐retest reliability, responsiveness and longitudinal validity of CARAT10.MethodsAdults with asthma and allergic rhinitis were enrolled at 4 outpatient clinics of Portuguese central hospitals. At each of the two visits, 4 to 6 weeks apart, patients filled out CARAT10 and additional questionnaires, followed by a medical evaluation blinded to the questionnaires’ answers.ResultsFrom the 62 patients included, 51 patients completely filled out CARAT10 at both visits. The test‐retest reliability, computed as an intra‐class correlation coefficient, was 0.82. Regarding responsiveness, a significant change (p = 0.002) of CARAT10 score in clinically unstable patients was observed (95%CI ‐5.08; ‐1.31) and the Guyatt's responsiveness index was 1.54. As for the longitudinal validity assessment, the correlation coefficients of the changes of CARAT10 scores with those of ACQ5 and symptoms VAS ranged from 0.49 to 0.65, while with the physician assessment of control they ranged from 0.31 to 0.41.ConclusionCARAT10 has good test‐retest reliability, responsiveness and longitudinal validity. It can be used to assess control of allergic rhinitis and asthma, both to compare groups in clinical studies and to evaluate individual patients in clinical practice.
Preparation of nanostructured TiO2-based photocatalyst by controlling the calcining temperature and pH
Authors: Uddin Mohammed Jasim , Islam Md Akhtarul , Haque Sheikh Ariful , Hasan Saidul , Amin Mohammad Shaiful Alam , Rahman Mohammed Mastabur 
Published: August 2012

Abstract
Nanostructured TiO2 has been synthesized using one-step sol–gel method and characterized by different characterization techniques (SEM, EDS, XRD, and UV–vis spectroscopy). The photocatalytic degradation of methylene blue (MB) and Congo red (CR) is studied with the synthesized TiO2. The photocatalytic degradation data has been validated using several kinetic models. The TiO2 showed efficient photocatalytic degradation performance on MB and CR. In addition to this, the effect of pH on the photocatalytic degradation has been investigated. The TiO2 showed enhanced photocatalytic performance in basic media than that in neutral or acidic ones.
Robust geophysical integration through structure-coupled joint inversion and multispectral fusion of seismic reflection, magnetotelluric, magnetic, and gravity images: Example from Santos Basin, offshore Brazil
Authors: Gallardo L. A. , Fontes S. L. , Meju M. A. , Buonora M. P. , de Lugao P. P. 
Published: August 2012

We have applied a crossgradient joint inversion and geospectral visualization method to marine seismic reflection, magnetotelluric, gravity, and magnetic data sets acquired along a 162 km profile across a segment of Santos Basin oil province in the continental margin of southeast Brazil. The main exploration targets are the top of the fractured Precambrian crystalline basement and any concealed basement grabens, the overlying presalt and salt/carbonate deposits, and the postsalt cover deposits. The results of joint inversion clearly mapped the various units and are a significant improvement over previous models derived from separate 2D seismic reflection processing and 2D magnetotelluric imaging. Additionally, multispectral fusion of these models resulted in a single image that permits highly constrained geologic interpretations enabling a better understanding of basin architecture. We suggest that joint inversion and image fusion is the way forward for effective geophysical integration.
Effects of Age and Serum 25-OH-Vitamin D on Serum Parathyroid Hormone Levels
Authors: Valcour A. , Blocki F. , Hawkins D. M. , Rao Sudhaker D. 
Published: August 2012

Context:
Several studies define optimal serum 25-hydroxyvitamin D (25-OHD) levels based on serum PTH level reaching an asymptote. However, results differ widely, ranging from 25-OHD levels of 12–44 ng/ml: many studies are constrained by small sample size.

Objective:
The objective of the study was to determine the relationship between serum PTH and 25-OHD levels and age in a very large reference laboratory database.

Design:
This was a detailed cross-sectional analysis of 312,962 paired serum PTH and 25-OHD levels measured from July 2010 to June 2011.

Results:
Median PTH levels and the proportion of patients (PTH &gt; 65 pg/ml), from 63 successive 25-OHD frequency classes of 5000 patients, provide smooth, exceptionally well-fitted curves (R2 = 0.994 and R2 = 0.995, respectively) without discernible inflection points or asymptotes but with striking age dependencies. Serum 25-OHD was below the recent Institute of Medicine sufficiency guidance of 20 ng/ml in 27% (85,000) of the subjects. More importantly, 40 and 51% of subjects (serum 25-OHD &lt;20 and 10 ng/ml, respectively) had biochemical hyperparathyroidism (PTH &gt; 65 pg/ml).

Conclusions:
This analysis, despite inevitable inherent limitations, introduces several clinical implications. First, median 25-OHD-dependent PTH levels revealed no threshold above which increasing 25-OHD fails to further suppress PTH. Second, the large number of subjects with 25-OHD deficiency and hyperparathyroidism reinforces the Third International Workshop on Asymptomatic Primary Hyper parathyroidism's recommendations to test for, and replete, vitamin D depletion before considering parathyroidectomy. Third, strong age dependency of the PTH-25-OHD relationship likely reflects the composite effects of age-related decline in calcium absorption and renal function. Finally, this unselected large population database study could guide clinical management of patients based on an age-dependent, PTH-25-OHD continuum.
The effects of a variable temperature regime on the physiology of the reef-building coralSeriatopora hystrix: results from a laboratory-based reciprocal transplant
Authors: Mayfield Anderson , Chan Pei-Hsun , Putnam Hollie M , Chen Chii-Shiarng , Fan Tung-Yung 
Published: August 2012

SummaryIn order to understand the effects of global climate change on reef-building corals, a thorough investigation of their physiological mechanisms of acclimatization is warranted. However, static temperature manipulations may underestimate the thermal complexity of the reefs in which many corals live. For instance, corals of Houbihu, Taiwan experience up to 10°C changes in temperature over the course of a day during spring tide upwelling events. To better understand the phenotypic plasticity of these corals, a laboratory-based experiment was conducted whereby specimens of Seriatopora hystrix (Dana, 1846) from the upwelling reef, Houbihu, and conspecifics from a non-upwelling reef (Houwan) were exposed to both a stable seawater temperature (26°C) and a regime characterized by a 6°C fluctuation (23-29°C) over a 12 hour period for seven days. A suite of physiological and molecular parameters was measured in samples of both treatments, as well as in experimental controls, in order to determine site of origin (SO) and temperature treatment (TT) responses. Only chlorophyll a concentration (chl-a) and growth demonstrated the hypothesized trend of higher levels when exposed to a TT that mimicked SO conditions. On the other hand, chl-a, maximum dark-adapted quantum yield of photosystem II (FV/FM), and Symbiodinium ribulose-1,5-bisphosphate carboxylase/oxygenase (rbcL), photosystem I (psI, subunit III), and phosphoglycolate phosphatase (pgpase) mRNA expression demonstrated significant TT effects. Specifically, these parameters were higher in samples exposed to a variable temperature regime, suggesting that S. hystrix may acclimate to fluctuating temperatures by increasing its capacity for photosynthesis.
Wingbeat kinematics and motor control of yaw turns in Anna's hummingbirds (Calypte anna)
Authors: Altshuler Douglas , Quicazán-Rubio Elsa , Segre Paolo M , Middleton Kevin 
Published: August 2012

SummaryThe biomechanical and neuromuscular mechanisms used by different animals to generate turns in flight are highly variable. Body size and body plan exert some influence, e.g., birds typically roll their body to orient forces generated by the wings whereas insects are capable of turning via left-right wingbeat asymmetries. Turns are also relatively brief and have low repeatability with almost every wingbeat serving a different function throughout the change in heading. Here we present an analysis of Anna’s hummingbirds (Calypte anna) as they fed continuously from an artificial feeder revolving around the outside of the animal. This setup allowed for examination of sustained changes in yaw without requiring any corresponding changes in pitch, roll, or body position. Hummingbirds sustained yaw turns by expanding the wing stroke amplitude of the outer wing during the downstroke and by altering the deviation of the wingtip path during both downstroke and upstroke. The latter led to a shift in the inner-outer stroke plane angle during the upstroke and shifts in the elevation of the stroke plane and in the deviation of the wingtip path during both strokes. These features are generally more similar to how insects, as opposed to birds, turn. However, time series analysis also revealed considerable stroke-to-stroke variation. Changes in the stroke amplitude and the wingtip velocity were highly cross-correlated as were changes in the stroke deviation and the elevation of the stroke plane. As was the case for wingbeat kinematics, electromyogram recordings from pectoral and wing muscles were highly variable, but no correlations were found between these two features of motor control. The high variability of both kinematic and muscle activation features indicates a high level of wingbeat-to-wingbeat adjustments during sustained yaw. The activation timing of the muscles was more repeatable than the activation intensity, which suggests that the former may be constrained by harmonic motion and that the latter may play a large role in kinematic adjustments. Comparing the revolution frequency of the feeder to measurements of free flight yaws reveals that feeder tracking, even at one revolution every two seconds, is well below the maximum yaw capacity of the hummingbirds.
Higher lipoprotein-associated phospholipase A2 levels are associated with coronary atherosclerosis documented by coronary angiography
Authors: Dohi Tomotaka , Miyauchi Katsumi , Ohkawa Ryunosuke , Nakamura Kazuhiro , Thuboi Shuta , Ogita Manabu , Miyazaki Tadashi , Nishino Akihisa , Yokoyama Ken , Kurata Takeshi , Yatomi Yutaka , Daida Hiroyuki 
Published: August 2012

Background Lipoprotein-associated phospholipase A2 (Lp-PLA2) has been proposed as an inflammatory marker of cardiovascular disease. The present study investigates associations between Lp-PLA2 and other important biomarkers in Japanese patients with coronary artery disease. Methods We measured Lp-PLA2 levels in 141 consecutive patients (age 62.6 ± 3.8 years; men 69.2%) with angiographic evidence of coronary artery disease (acute coronary syndrome [ACS]; n = 38), stable angina pectoris (SAP; n = 72) or with angiographically normal coronary arteries (NCA; n = 31). Results Levels of Lp-PLA2 significantly correlated with low-density lipoprotein-cholesterol ( r = 0.302), homocysteine ( r = 0.528) and paraoxonase ( r = 0.401) in all patients (all P < 0.01). Levels of Lp-PLA2 were significantly higher in patients with coronary atherosclerosis (ACS and SAP) than with NCA ( P < 0.05). Levels of highly sensitive C-reactive protein were significantly higher in patients with ACS than with SAP and NCA (both P < 0.05). Multivariate logistic regression analyses revealed that higher Lp-PLA2 levels were independently associated with coronary atherosclerosis (odds ratio: 1.058; 95% confidence interval: 1.012–1.121; P = 0.001). Conclusions Higher Lp-PLA2 levels are associated with coronary atherosclerosis independently of traditional coronary risk factors. Thus, Lp-PLA2 is a novel biomarker of coronary atherosclerosis in Japanese patients.