bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vascular patterns in the heads of crocodilians: blood vessels and sites of thermal exchange
Authors: Porter William Ruger , Sedlmayr Jayc C. , Witmer Lawrence M. 
Published: September 2016

AbstractExtant crocodilians are a highly apomorphic archosaur clade that is ectothermic, yet often achieve large body sizes that can be subject to higher heat loads. Therefore, the anatomical and physiological roles that blood vessels play in crocodilian thermoregulation need further investigation to better understand how crocodilians establish and maintain cephalic temperatures and regulate neurosensory tissue temperatures during basking and normal activities. The cephalic vascular anatomy of extant crocodilians, particularly American alligator (Alligator mississippiensis) was investigated using a differential‐contrast, dual‐vascular injection technique and high resolution X‐ray micro‐computed tomography (μCT). Blood vessels were digitally isolated to create representations of vascular pathways. The specimens were then dissected to confirmCTresults. Sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in evaporative cooling and cephalic thermoregulation in other diapsids. Blood vessels to and from sites of thermal exchange were studied to detect conserved vascular patterns and to assess their ability to deliver cooled blood to neurosensory tissues. Within the orbital region, both the arteries and veins demonstrated consistent branching patterns, with the supraorbital, infraorbital, and ophthalmotemporal vessels supplying and draining the orbit. The venous drainage of the orbital region showed connections to the dural sinuses via the orbital veins and cavernous sinus. The palatal region demonstrated a vast plexus that comprised both arteries and veins. The most direct route of venous drainage of the palatal plexus was through the palatomaxillary veins, essentially bypassing neurosensory tissues. Anastomotic connections with the nasal region, however, may provide an alternative route for palatal venous blood to reach neurosensory tissues. The nasal region in crocodilians is probably the most prominent site of thermal exchange, as it offers a substantial surface area and is completely surrounded by blood vessels. The venous drainage routes from the nasal region offer routes directly to the dural venous sinuses and the orbit, offering evidence of the potential to directly affect neurosensory tissue temperatures. The evolutionary history of crocodilians is complex, with large‐bodied, terrestrial, and possibly endothermic taxa that may have had to deal with thermal loads that likely provided the anatomical building‐blocks for such an extensive vascularization of sites of thermal exchange. A clear understanding of the physiological abilities and the role of blood vessels in the thermoregulation of crocodilians neurosensory tissues is not available but vascular anatomical patterns of crocodilian sites of thermal exchange indicate possible physiological abilities that may be more sophisticated than in other extant diapsids.
Mesenchymal stem cells and vascular regeneration
Authors: Gu Wenduo , Hong Xuechong , Potter Claire , Qu Aijuan , Xu Qingbo 
Published: September 2016

AbstractIn recent years, MSCs have emerged as a promising therapeutic cell type in regenerative medicine. They hold great promise for treating cardiovascular diseases, such as myocardial infarction and limb ischemia. MSCs may be utilized in both cell‐based therapy and vascular graft engineering to restore vascular function, thereby providing therapeutic benefits to patients. The efficacy of MSCs lies in their multipotent differentiation ability toward vascular smooth muscle cells, endothelial cells and other cell types, as well as their capacity to secrete various trophic factors, which are potent in promoting angiogenesis, inhibiting apoptosis and modulating immunoreaction. Increasing our understanding of the mechanisms of MSC involvement in vascular regeneration will be beneficial in boosting present therapeutic approaches and developing novel ones to treat cardiovascular diseases. In this review, we aim to summarize current progress in characterizing the in vivo identity of MSCs, to discuss mechanisms involved in cell‐based therapy utilizing MSCs, and to explore current and future strategies for vascular regeneration.
Amiloride modifies the progression of lithium‐induced renal interstitial fibrosis
Authors: Kalita‐De Croft Priyakshi , Bedford Jennifer J , Leader John P , Walker Robert J 
Published: September 2016

ABSTRACTAimLong‐term administration of lithium has been associated with the development of a chronic interstitial fibrosis in addition to nephrogenic diabetes insipidus (NDI). Earlier studies have demonstrated that amiloride, by blocking the epithelial sodium channel ENaC and thus preventing lithium uptake into the principal cells of the collecting ducts, can partially reverse lithium‐induced NDI. However, there are no long‐term studies examining whether or not amiloride also modifies the progressive chronic interstitial fibrosis and tubular atrophy often evident with long‐term lithium exposure.MethodsUsing an established animal model of lithium‐induced chronic interstitial fibrosis, rats were treated with amiloride and lithium for 5 months following 1 month of exposure to lithium alone and compared with control animals and those given only lithium.Results and ConclusionsIn this study, the 5 months of amiloride therapy partially mitigated the lithium‐induced NDI and limited the further progression of lithium‐induced kidney fibrosis. This improvement was associated with decreased expression of the pro‐fibrotic connective tissue growth factor (CTGF), along with reduced myofibroblast infiltration and decreased collagen deposition around the distended cortical collecting ducts. This may, in part, be mediated by modifying lithium‐induced alterations in β‐catenin activity through its effects on GSK‐3β.
Biparental chloroplast inheritance leads to rescue from cytonuclear incompatibility
Authors: Barnard‐Kubow Karen B. , McCoy Morgan A. , Galloway Laura F. 
Published: September 2016

Summary

Although organelle inheritance is predominantly maternal across animals and plants, biparental chloroplast inheritance has arisen multiple times in the angiosperms. Biparental inheritance has the potential to impact the evolutionary dynamics of cytonuclear incompatibility, interactions between nuclear and organelle genomes that are proposed to be among the earliest types of genetic incompatibility to arise in speciation.

We examine the interplay between biparental inheritance and cytonuclear incompatibility in Campanulastrum americanum, a plant species exhibiting both traits. We first determine patterns of chloroplast inheritance in genetically similar and divergent crosses, and then associate inheritance with hybrid survival across multiple generations.

There is substantial biparental inheritance in C. americanum. The frequency of biparental inheritance is greater in divergent crosses and in the presence of cytonuclear incompatibility. Biparental inheritance helps to mitigate cytonuclear incompatibility, leading to increased fitness of F1 hybrids and recovery in the F2 generation.

This study demonstrates the potential for biparental chloroplast inheritance to rescue cytonuclear compatibility, reducing cytonuclear incompatibility's contribution to reproductive isolation and potentially slowing speciation. The efficacy of rescue depended upon the strength of incompatibility, with a greater persistence of weak incompatibilities in later generations. These findings suggest that incompatible plastids may lead to selection for biparental inheritance.
A three‐dimensional alginate system for in vitro culture of cumulus‐denuded feline oocytes
Authors: Morselli MG , Canziani S , Vigo D , Luvoni GC 
Published: September 2016

ContentsIn the case of high valuable individuals with very precious genetic material, widening the genetic pool including gametes with poor morphological characteristics, as cumulus‐denuded oocytes (CDOs), could be an option. To improve the in vitro culture of low‐competence feline CDOs, an enriched three‐dimensional (3D) system in association with competent cumulus–oocyte complexes (COCs) was developed. For this purpose, domestic cat CDOs were cultured with or without companion COCs in the 3D barium alginate microcapsules. The overall viability and the meiotic progression of feline CDOs cocultured with COCs or cultured separately in 3D or in 2D (traditional microdrops) system were compared. The 3D system was able to support viability and meiotic resumption of the feline oocytes, as well as the 2D microdrops. In 3D microcapsules, the presence of COCs resulted in a higher viability of CDOs (91.1%, p < .05), than that obtained without COCs or in 2D microdrops (71.2% and 67.3%, respectively), but the percentages of meiotic resumption were similar of those of CDOs cultured separately (55.4% vs. 40.4%, p > .05). It is notable that the presence of CDOs seemed to enhance the meiotic progression of the associated COCs. In conclusion, the 3D barium alginate microcapsules are a suitable system for feline oocytes in vitro culture, but more specific enriched conditions should be developed to improve the CDOs full competence in vitro.
Cytomegalovirus sinusitis complicated by orbital apex syndrome in an immunocompromised host
Authors: Nomura Jim H. , Eichhorn Knut , Cao Thai M. , Sahebi Firoozeh 
Published: September 2016

AbstractSinusitis in immunocompromised patients can be caused by a wide variety of pathogens, primarily bacterial and fungal in nature. Tissue invasion can extend into the orbital apex and result in ophthalmoplegia and blindness. We report the first histologically proven case, to our knowledge, caused by cytomegalovirus infection.
Induction, management, and complications of streptozotocin‐induced diabetes mellitus in rhesus monkeys
Authors: Kim Jong‐Min , Shin Jun‐Seop , Min Byoung‐Hoon , Kim Hyun‐Je , Kim Jung‐Sik , Yoon Il‐Hee , Jeong Won‐Young , Lee Ga‐Eul , Kim Min‐Sun , Kim Ju‐Eun , Jin Sang‐Man , Park Chung‐Gyu 
Published: September 2016

AbstractBackgroundDiabetes mellitus (DM) model using streptozotocin (STZ) which induces chemical ablation of β cell in the pancreas has been widely used for various research purposes in non‐human primates. However, STZ has been known to have a variety of adverse effects such as nephrotoxicity, hepatotoxicity, and even mortality. The purpose of this study is to report DM induction by STZ, toxicity associated with STZ and procedure and complication of exogenous insulin treatment for DM management in rhesus monkeys (Macaca mulatta) that are expected to be transplanted with porcine islets within 2 months.MethodsStreptozotocin (immediately dissolved in normal saline, 110 mg/kg) was slowly infused via central catheter for 10 minutes in 22 rhesus monkeys. Clinical signs, complete blood count and blood chemistry were monitored to evaluate toxicity for 1 week after STZ injection. Monkey basal C‐peptides were measured and intravenous glucose tolerance test was performed to confirm complete induction of DM. Exogenous insulin was subcutaneously injected to maintain blood glucose in diabetic rhesus monkeys and the complications were recorded while in insulin treatment.ResultsSevere salivation and vomiting were observed within 1 hour after STZ injection in 22 rhesus monkeys. One monkey died at 6 hours after STZ injection and the reason for the death was unknown. Pancreatitis was noticed in one monkey after STZ injection, but the monkey recovered after 5 days by medical treatment. Serum total protein and albumin decreased whereas the parameters for the liver function such as aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase significantly increased (P<.05) after STZ injection, but they were resolved within 1 week. Azotemia was not observed. Monkey fasting C‐peptide levels after STZ injection were <0.1 ng/mL in 18 rhesus monkeys, but 0.34, 0.22, 0.16 ng/mL in three monkeys, respectively. The value of daily insulin requirement was 0.92±0.26IU/kg/d (range=0.45–1.29) in the monkeys. Diabetic ketoacidosis was observed in one rhesus monkeys, but the monkey recovered after 24 hours by fluid and insulin treatment.ConclusionsStreptozotocin was effective for inducing DM in rhesus monkeys, but various adverse effects such as pancreatitis, liver toxicity or death were observed. Therefore, careful and suitable medical managements should be implemented to eliminate the risks of mortality and severe adverse effects.
Molecular mechanisms of Slo2 K+ channel closure
Authors: Giese M. Hunter , Gardner Alison , Hansen Angela , Sanguinetti Michael C. 
Published: September 2016

Key points
Intracellular Na+‐activated Slo2 potassium channels are in a closed state under normal physiological conditions, although their mechanisms of ion permeation gating are not well understood.
A cryo‐electron microscopy structure of Slo2.2 suggests that the ion permeation pathway of these channels is closed by a single constriction of the inner pore formed by the criss‐crossing of the cytoplasmic ends of the S6 segments (the S6 bundle crossing) at a conserved Met residue.
Functional characterization of mutant Slo2 channels suggests that hydrophobic interactions between Leu residues in the upper region of the S6 segments contribute to stabilizing the inner pore in a non‐conducting state.
Mutation of the conserved Met residues in the S6 segments to the negatively‐charged Glu did not induce constitutive opening of Slo2.1 or Slo2.2, suggesting that ion permeation of Slo2 channels is not predominantly gated by the S6 bundle crossing.
AbstractLarge conductance K+‐selective Slo2 channels are in a closed state unless activated by elevated [Na+]i. Our previous studies suggested that the pore helix/selectivity filter serves as the activation gate in Slo2 channels. In the present study, we evaluated two other potential mechanisms for stabilization of Slo2 channels in a closed state: (1) dewetting and collapse of the inner pore (hydrophobic gating) and (2) constriction of the inner pore by tight criss‐crossing of the cytoplasmic ends of the S6 α‐helical segments. Slo2 channels contain two conserved Leu residues in each of the four S6 segments that line the inner pore region nearest the bottom of the selectivity filter. To evaluate the potential role of these residues in hydrophobic gating, Leu267 and Leu270 in human Slo2.1 were each replaced by 15 different residues. The relative conductance of mutant channels was highly dependent on hydrophilicity and volume of the amino acid substituted for Leu267 and was maximal with L267H. Consistent with their combined role in hydrophobic gating, replacement of both Leu residues with the isosteric but polar residue Asn (L267N/L270N) stabilized channels in a fully open state. In a recent cryo‐electron microscopy structure of chicken Slo2.2, the ion permeation pathway of the channel is closed by a constriction of the inner pore formed by criss‐crossing of the S6 segments at a conserved Met. Inconsistent with the S6 segment crossing forming the activation gate, replacement of the homologous Met residues in human Slo2.1 or Slo2.2 with the negatively‐charged Glu did not induce constitutive channel opening.
Online 4D ultrasound guidance for real‐time motion compensation by MLC tracking
Authors: Ipsen Svenja , Bruder Ralf , O’Brien Rick , Keall Paul J. , Schweikard Achim , Poulsen Per R. 
Published: September 2016

PurposeWith the trend in radiotherapy moving toward dose escalation and hypofractionation, the need for highly accurate targeting increases. While MLC tracking is already being successfully used for motion compensation of moving targets in the prostate, current real‐time target localization methods rely on repeated x‐ray imaging and implanted fiducial markers or electromagnetic transponders rather than direct target visualization. In contrast, ultrasound imaging can yield volumetric data in real‐time (3D + time = 4D) without ionizing radiation. The authors report the first results of combining these promising techniques—online 4D ultrasound guidance and MLC tracking—in a phantom.MethodsA software framework for real‐time target localization was installed directly on a 4D ultrasound station and used to detect a 2 mm spherical lead marker inside a water tank. The lead marker was rigidly attached to a motion stage programmed to reproduce nine characteristic tumor trajectories chosen from large databases (five prostate, four lung). The 3D marker position detected by ultrasound was transferred to a computer program for MLC tracking at a rate of 21.3 Hz and used for real‐time MLC aperture adaption on a conventional linear accelerator. The tracking system latency was measured using sinusoidal trajectories and compensated for by applying a kernel density prediction algorithm for the lung traces. To measure geometric accuracy, static anterior and lateral conformal fields as well as a 358° arc with a 10 cm circular aperture were delivered for each trajectory. The two‐dimensional (2D) geometric tracking error was measured as the difference between marker position and MLC aperture center in continuously acquired portal images. For dosimetric evaluation, VMAT treatment plans with high and low modulation were delivered to a biplanar diode array dosimeter using the same trajectories. Dose measurements with and without MLC tracking were compared to a static reference dose using 3%/3 mm and 2%/2 mm γ‐tests.ResultsThe overall tracking system latency was 172 ms. The mean 2D root‐mean‐square tracking error was 1.03 mm (0.80 mm prostate, 1.31 mm lung). MLC tracking improved the dose delivery in all cases with an overall reduction in the γ‐failure rate of 91.2% (3%/3 mm) and 89.9% (2%/2 mm) compared to no motion compensation. Low modulation VMAT plans had no (3%/3 mm) or minimal (2%/2 mm) residual γ‐failures while tracking reduced the γ‐failure rate from 17.4% to 2.8% (3%/3 mm) and from 33.9% to 6.5% (2%/2 mm) for plans with high modulation.ConclusionsReal‐time 4D ultrasound tracking was successfully integrated with online MLC tracking for the first time. The developed framework showed an accuracy and latency comparable with other MLC tracking methods while holding the potential to measure and adapt to target motion, including rotation and deformation, noninvasively.
An iterative projection‐based motion estimation and compensation scheme for head x‐ray CT
Authors: Sun Tao , Kim Jung‐Ha , Fulton Roger , Nuyts Johan 
Published: September 2016

PurposeAlthough current computed tomography (CT) systems can scan the head in a very short time, patient motion sometimes still induces artifacts. If motion occurs, one has to repeat the scan; to avoid motion, sedation or anesthesia is sometimes applied.MethodsThe authors propose a method to iteratively estimate and compensate this motion during the reconstruction. In every iteration, the rigid motion was estimated view‐by‐view and then used to update the system matrix. A multiresolution scheme was used to speed up the convergence of this joint estimation of the image and the motion of the subject. A final iterative reconstruction was performed with the last motion estimate.ResultsThe method was evaluated on simulations, patient scans, and a phantom study. The quality of the reconstructed images was improved substantially after the compensation. In simulation and phantom studies, root‐mean‐square error was reduced and mean structural similarity was increased. In the patient studies, most of the motion blurring in the reconstructed images disappeared after the compensation.ConclusionsThe proposed method effectively eliminated motion‐induced artifacts in head CT scans. Since only measured raw data are needed for the motion estimation and compensation, the proposed method can be applied retrospectively to clinical helical CT scans affected by motion.
Technical assessment of a prototype cone‐beam CT system for imaging of acute intracranial hemorrhage
Authors: Xu Jennifer , Sisniega Alejandro , Zbijewski Wojciech , Dang Hao , Stayman J. Webster , Mow Michael , Wang Xiaohui , Foos David H. , Koliatsos Vassillis E. , Aygun Nafi , Siewerdsen Jeffrey H. 
Published: September 2016

PurposeA cone‐beam CT scanner has been developed for detection and monitoring of traumatic brain injury and acute intracranial hemorrhage (ICH) at the point of care. This work presents a technical assessment of imaging performance and dose for the scanner in phantom and cadaver studies as a prerequisite to clinical translation.MethodsThe scanner incorporates a compact, rotating‐anode x‐ray source and a flat‐panel detector (43 × 43 cm2) on a mobile U‐arm gantry with source‐axis distance = 550 mm and source‐detector distance = 1000 mm. Central and peripheral doses were measured in 16 cm diameter CTDI phantoms using a 0.6 cm3 Farmer ionization chamber for various scan techniques and as a function of longitudinal position, including out of field. Spatial resolution, contrast, noise, and image uniformity were assessed in quantitative and anthropomorphic head phantoms. Two reconstruction protocols were evaluated, including filtered backprojection (FBP) for high‐resolution bone imaging and penalized weighted least squares (PWLS) reconstruction for low‐contrast soft tissue (ICH) visualization. A fresh cadaver was imaged with and without simulated ICH using the scanner as well as a diagnostic multidetector CT (MDCT) scanner using a standard head protocol. Images were interpreted by a fellowship‐trained neuroradiologist for imaging tasks of ICH detection, gray‐white‐CSF differentiation, detection of midline shift, and fracture detection.ResultsThe nominal scan protocol involved 720 projections acquired over a 360° orbit at 100 kV and 216 mAs, giving a dose (weighted CTDI) of 22.8 mGy (∼1.2 mSv effective dose). Out‐of‐field dose decreased to <10% within 6 cm of the field edge (approximate to the thyroid position). Image uniformity demonstrated <1% variation between the edge of the field (near the cranium) and center of the image. The high‐resolution FBP reconstruction protocol showed ∼0.9 mm point spread function (PSF) full‐width at half‐maximum (FWHM). The smooth PWLS reconstruction protocol yielded ∼1.2 mm PSF FWHM and contrast‐to‐noise ratio exceeding 5.7 in ∼50 HU spherical ICH, resulting in conspicuous depiction of ICH down to ∼2 mm (the smallest diameter investigated). Cadaver images demonstrated good differentiation of brain and CSF (sufficient, but inferior to MDCT, recognizing that the CBCT dose was one‐third that of MDCT), excellent visualization of cranial sutures and fracture (potentially superior to MDCT), clear detection of midline shift, and conspicuous detection of ICH.ConclusionsTechnical assessment of the prototype demonstrates dose characteristics and imaging performance consistent with point‐of‐care detection and monitoring of head injury—most notably, conspicuous detection of ICH—and supports translation of the system to clinical studies.
Genome Sequences of 11 Human Vaginal
Actinobacteria
Strains
Authors: Lewis Amanda L. , Deitzler Grace E. , Ruiz Maria J. , Weimer Cory , Park SoEun , Robinson Lloyd S. , Hallsworth-Pepin Kymberlie , Wollam Aye , Mitreva Makedonka , Lewis Warren G. 
Published: September 2016

ABSTRACT

The composition of the vaginal microbiota is an important health determinant. Several members of the phylum
Actinobacteria
have been implicated in bacterial vaginosis, a condition associated with many negative health outcomes. Here, we present 11 strains of vaginal
Actinobacteria
(now available through BEI Resources) along with draft genome sequences.
Complete Genome Sequence of a
Myoviridae
Bacteriophage Infecting Salmonella enterica Serovar Typhimurium
Authors: Paradiso Rubina , Orsini Massimiliano , Bolletti Censi Sergio , Borriello Giorgia , Galiero Giorgio 
Published: September 2016

ABSTRACT

The bacteriophage 118970_sal3 was isolated from water buffalo feces in southern Italy, exhibiting lytic activity against
Salmonella enterica
serovar Typhimurium. This bacteriophage belongs to the
Myoviridae
family and has a 39,464-bp double-stranded DNA (ds-DNA) genome containing 53 coding sequences (CDSs).