bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gamma Knife surgery for the treatment of 5 to 15 metastases to the brain
Authors: Salvetti David J. , Nagaraja Tara G. , McNeill Ian T. , Xu Zhiyuan , Sheehan Jason 
Published: March 2013

Object
It has been generally accepted that Gamma Knife surgery (GKS) is an effective primary or adjunct treatment for patients with 1–4 metastases to the brain. The number of studies detailing the use of GKS for 5 or more brain metastases, however, remains minimal. The aim of the current retrospective study was to elucidate the utility of GKS in patients with 5–15 brain metastases.

Methods
Patients were chosen for GKS based on prior MRI of these metastatic lesions and a known primary cancer diagnosis. Magnetic resonance imaging was used post-GKS to assess tumor control; patients were also followed up clinically. Overall survival (OS) from the date of GKS was used as the primary end point. Statistical analysis was performed to identify prognostic factors related to OS.

Results
Between 2003 and 2012, 96 patients were treated for a total of 704 metastatic brain lesions. The histology of these lesions varied among non–small cell lung cancer (NSCLC), breast cancer, melanoma, renal cancer, and other more rare carcinomas. At the initial treatment, 18 of the patients (18.8%) were categorized in Recursive Partitioning Analysis (RPA) Class 1 and 77 (80.2%) in RPA Class 2; none were in RPA Class 3. The median number of treated lesions was 7 (mean 7.13), and the median planned treatment volume was 6.12 cm3 (range 0.42–57.83 cm3) per patient. The median clinical follow-up was 4.1 months (range 0.1–40.70 months). Actuarial tumor control was calculated to be 92.4% at 6 months, 84.8% at 12 months, and 74.9% at 24 months post-GKS. The median OS was found to be 4.73 months (range 0.4–41.8 months). Multivariate analysis demonstrated that RPA class was a significant predictor of death (HR = 2.263, p = 0.038). Number of lesions, tumor histology, Graded Prognostic Assessment score, prior whole-brain radiation therapy, prior resection, prior chemotherapy, patient age, patient sex, controlled primary tumor, extracranial metastases, and planned treatment volume were not significant predictors of OS.

Conclusions
In patients with 5–15 brain metastases at presentation, the number of lesions did not predict survival after GKS; however, the RPA class was predictive of OS in this group of patients. Gamma Knife surgery for such patients offers an excellent rate of local tumor control.
White matter fiber tractography: why we need to move beyond DTI
Authors: Farquharson Shawna , Tournier J.-Donald , Calamante Fernando , Fabinyi Gavin , Schneider-Kolsky Michal , Jackson Graeme D. , Connelly Alan 
Published: March 2013

Object
Diffusion-based MRI tractography is an imaging tool increasingly used in neurosurgical procedures to generate 3D maps of white matter pathways as an aid to identifying safe margins of resection. The majority of white matter fiber tractography software packages currently available to clinicians rely on a fundamentally flawed framework to generate fiber orientations from diffusion-weighted data, namely diffusion tensor imaging (DTI). This work provides the first extensive and systematic exploration of the practical limitations of DTI-based tractography and investigates whether the higher-order tractography model constrained spherical deconvolution provides a reasonable solution to these problems within a clinically feasible timeframe.

Methods
Comparison of tractography methodologies in visualizing the corticospinal tracts was made using the diffusion-weighted data sets from 45 healthy controls and 10 patients undergoing presurgical imaging assessment. Tensor-based and constrained spherical deconvolution–based tractography methodologies were applied to both patients and controls.

Results
Diffusion tensor imaging–based tractography methods (using both deterministic and probabilistic tractography algorithms) substantially underestimated the extent of tracks connecting to the sensorimotor cortex in all participants in the control group. In contrast, the constrained spherical deconvolution tractography method consistently produced the biologically expected fan-shaped configuration of tracks. In the clinical cases, in which tractography was performed to visualize the corticospinal pathways in patients with concomitant risk of neurological deficit following neurosurgical resection, the constrained spherical deconvolution–based and tensor-based tractography methodologies indicated very different apparent safe margins of resection; the constrained spherical deconvolution–based method identified corticospinal tracts extending to the entire sensorimotor cortex, while the tensor-based method only identified a narrow subset of tracts extending medially to the vertex.

Conclusions
This comprehensive study shows that the most widely used clinical tractography method (diffusion tensor imaging–based tractography) results in systematically unreliable and clinically misleading information. The higher-order tractography model, using the same diffusion-weighted data, clearly demonstrates fiber tracts more accurately, providing improved estimates of safety margins that may be useful in neurosurgical procedures. We therefore need to move beyond the diffusion tensor framework if we are to begin to provide neurosurgeons with biologically reliable tractography information.
Anatomical feasibility of performing a nerve transfer from the femoral branch to bilateral pelvic nerves in a cadaver: a potential method to restore bladder function following proximal spinal cord injury
Authors: Brown Justin M. , Barbe Mary F. , Albo Michael E. , Ruggieri Michael R. 
Published: March 2013

Object
Nerve transfers are an effective means of restoring control to paralyzed somatic muscle groups and have recently been shown to be effective in denervated detrusor muscle in a canine model. A cadaveric study was performed to examine the anatomical feasibility of transferring femoral muscular nerve branches to vesical branches of the pelvic nerve as a method of potentially restoring innervation to control the detrusor muscle in humans.

Methods
Twenty cadavers were dissected bilaterally to expose pelvic and femoral muscular nerve branches. Ease of access and ability to transfer the nerves were assessed, as were nerve cross-sectional areas.

Results
The pelvic nerve was accessed at the base of the bladder, inferior to the ureter, and accompanied by inferior vesical vessels. Muscular branches of the femoral nerve to the vastus medialis and intermedius muscles (L-3 and L-4 origins) were followed distally for 17.4 ± 0.8 cm. Two muscle branches were split from the femoral nerve trunk, and tunneled inferior to the inguinal ligament. One branch was moved medially toward the base of the bladder and linked to the ipsilateral pelvic nerve. The second branch was tunneled superior to the bladder and linked to the contralateral pelvic nerve. The cross-sectional area of the pelvic nerve vesical branch was 2.60 ± 0.169 mm2 (mean ± SEM), and the femoral nerve branch at the suggested transection site was 4.40 ± 0.41 mm2.

Conclusions
Use of femoral nerve muscular branches from the vastus medialis and intermedius muscles for heterotopic nerve transfer of bilateral pelvic nerves is surgically feasible, based on anatomical location and cross-sectional areas.
Anatomical feasibility of C-2 pedicle screw fixation: the effect of variable angle interpolation of axial CT scans
Authors: Burke Lauren M. , Yu Warren D. , Ho Anthony , Wagner Timothy , O'Brien Joseph R. 
Published: March 2013

Object
Anatomical variability of the C-2 pedicle poses a challenge for C-2 fixation. The use of multidimensional CT scanning is not widely used but might be an asset to preoperative planning. Careful preoperative planning is imperative for instrumentation at C-2. Fine-cut, noncontrast CT scanning is a useful tool for delineating anatomy; however, the axis of the images is not always along the anatomical axis of the vertebra in question. The authors evaluated the suitability of C-2 pedicles for screw placement by using OsiriX (Pixmeo) software to change the gantry angle of CT angiograms to measure the anatomical dimensions of the C-2 pedicle.

Methods
The authors conducted a retrospective review of CT angiograms of the head and neck from 47 trauma patients seen consecutively at George Washington University Hospital. For each patient, 3 independent observers determined length and width of each C-2 pedicle (94 samples) by using OsiriX. OsiriX is a DICOM viewer that enables navigation and visualization in multidimensional imaging, such as 3D imaging, which was used for this study. Sex-specific measurements were also determined. Vertebral anatomy was studied to determine whether aberrant anatomy would preclude pedicle fixation. Statistical analyses were performed.

Results
Of the 47 patients, 27 were male. Overall mean C-2 pedicle widths and lengths were 8.272 ± 1.364 mm and 27.052 ± 3.471 mm, respectively. The average widths and lengths of the pedicle in female patients were 8.040 ± 1.262 mm and 27.241 ± 2.731 mm, respectively, and those in male patients were 8.444 ± 1.414 mm and 26.913 ± 3.933 mm, respectively. The sex difference was statistically significant for width (p = 0.012) but not for length (p = 0.41). On the basis of width, the percentages of pedicles that could tolerate a 3.5-mm and 4.0-mm screw were 98% and 97%, respectively. Vertebral anatomy precluded screw length greater than 14 mm for only 3 patients.

Conclusions
Using multidimensional CT or 3D imaging, the authors found that C-2 pedicles in over 90% of patients could tolerate 3.5-mm and 4.0-mm pedicle screws. Vertebral anatomy precluded use of screw lengths greater than 14 mm for only 3 (6%) of 47 patients. Therefore, the C-2 pedicle might be more tolerant of fixation than previously reported.
Phylogeography of North American herbaceous Smilax (Smilacaceae): Combined AFLP and cpDNA data support a northern refugium in the Driftless Area
Authors: Li Pan , Li Mimi , Shi Yin , Zhao Yunpeng , Wan Ying , Fu Chengxin , Cameron Kenneth M. 
Published: March 2013

• Premise of the study: The genetic structure of North American herbaceous Smilax, a clade of closely related understory herbs that has a wide and disjunct distribution, was investigated to test the hypothesis of whether a northern refugium in the upper Midwest may have existed for these plants during the last glaciation.• Methods: We analyzed 33 populations sampled from California and throughout the eastern United States using AFLP and chloroplast DNA sequence data.• Key results: Individuals of S. jamesii from northern California formed a clade sister to the eastern North American species, and they likely diverged from each other during the Pleistocene. Among the eastern species, two lineages were found on opposite sides of the Appalachian Mountains. The populations near the “Driftless Area” contained most of the chlorotypes found in the Midwest, including a unique one endemic to this area, and the AFLP data indicated that one population from this area has the highest frequency‐down‐weighted‐marker value.• Conclusions: This study, and others that have focused on mammals, amphibians, and woody plants, provides further evidence for the debate over whether the upper Midwest's “Driftless Area” may have hosted a biologically diverse northern glacial refugium. Herbaceous species of Smilax from eastern North American exhibit an Appalachian discontinuity. They appear to have persisted in multiple refugia both east and west of the Appalachians, with several populations persisting in situ through the Last Glacial Maximum (LGM). We suggest that they experienced localized expansion after the LGM, possibly followed by subsequent contact between the Midwest and the East Coastal lineages.
Hormonal interactions and gene regulation can link monoecy and environmental plasticity to the evolution of dioecy in plants
Authors: Golenberg Edward M. , West Nicholas W. 
Published: March 2013

Most models for dioecy in flowering plants assume that dioecy arises directly from hermaphroditism through a series of independent feminizing and masculinizing mutations that become chromosomally linked. However, dioecy appears to evolve most frequently through monoecious grades. The major genetic models do not explain the evolution of unisexual flowers in monoecious and submonoecious populations, nor do they account for environmentally induced sexual plasticity. In this review, we explore the roles of environmental stress and hormones on sex determination, and propose a model that can explain the evolution of dioecy through monoecy, and the mechanisms of environmental sex determination.Environmental stresses elicit hormones that allow plants to mediate the negative effects of the stresses. Many of these same hormones are involved in the regulation of floral developmental genes. Recent studies have elucidated the mechanisms whereby these hormones interact and can act as switchpoints in regulatory pathways. Consequently, differential concentrations of plant hormones can regulate whole developmental pathways, providing a mechanism for differential development within isogenic individuals such as seen in monoecious plants. Sex‐determining genes in such systems will evolve to generate clusters of coexpressed suites. Coexpression rather than coinheritance of gender‐specific genes will define the sexual developmental fate. Therefore, selection for gender type will drive evolution of the regulatory sequences of such genes rather than their synteny. Subsequent mutations to hyper‐ or hyposensitive alleles within the hormone response pathway can result in segregating dioecious populations. Simultaneously, such developmental systems will remain sensitive to external stimuli that modify hormone responses.
Polymorphic microsatellite loci for Virola sebifera (Myristicaceae) derived from shotgun 454 pyrosequencing
Authors: Wei Na , Dick Christopher W. , Lowe Andrew J. , Gardner Michael G. 
Published: March 2013

• Premise of the study: Polymorphic microsatellite loci were characterized in the dioecious neotropical rainforest tree Virola sebifera. The markers will be used to study ecological and genetic impacts of hunting and landscape change in this vertebrate‐dispersed, insect‐pollinated tree species.• Methods and Results: Simple sequence repeat (SSR) markers were screened from genomic libraries of South American V. sebifera obtained by shotgun 454 pyrosequencing. Primer pairs were tested on Panamanian samples (N = 42). Approximately 52% of the 61 tested SSR markers amplified, and 16% were polymorphic. Ten selected polymorphic SSR loci contained seven to 15 alleles per locus, and polymorphic information content averaged 0.694. Observed heterozygosity ranged from 0.465 to 0.905, and expected heterozygosity was between 0.477 and 0.876.• Conclusions: The 10 polymorphic loci will be useful in studying gene flow and genetic structure at local and regional spatial scales in V. sebifera.
An anthropological genetic perspective on creolization in the anglophone caribbean
Authors: Torres Jada Benn , Stone Anne C. , Kittles Rick 
Published: March 2013

ABSTRACTVariable socio‐cultural influences developed in the colonial Caribbean as a result of competing European hegemonic rule. In this study, we examine how colonial regulations regarding social hierarchies and mate choice worked to influence the genetic landscape of contemporary African Caribbean populations. To this end, 420 individuals from Dominica, Grenada, St. Kitts, St. Lucia, St. Thomas, St. Vincent, Jamaica, and Trinidad were genotyped for 105 autosomal ancestry informative markers. Based on these data, population substructure and admixture were assessed using an exact test, a model‐based clustering method, and principal components analysis. On average, individual admixture estimates of the pooled African Caribbean sample were 77% (SD ± 18%) West African, 15% (SD ± 15%) European, and 7.7% (SD ± 8%) Native American. In general, ancestry estimates were significantly different between Dominica and all other islands. Genetic structure analyses indicated subdivision into two subpopulations on most islands. Finally, unlike all of the other Caribbean populations that clustered adjacent to African populations, the Dominican population was more intermediate between the three parental groups in the principal components plot. As a result of the significant French influence throughout Dominican history, Dominica did not have the same cultural influences that typified other Anglophone colonies. Consequently, there were different social hierarchies and resulting mate choices on Dominica compared with the other considered islands. This study highlights the complex socio‐cultural history of a broad region of the Caribbean and attests to the interplay between social and biological factors in shaping the genetic diversity present in present‐day communities. Am J Phys Anthropol 151:135–143, 2013. © 2013 Wiley Periodicals, Inc.
Method to help ensure survival of a very small skin paddle of pectoralis major musculocutaneous flap in head and neck reconstruction
Authors: Kim Eun Key , Yang Sung Jun , Choi Seung Ho 
Published: March 2013

AbstractBackgroundWhen the required dimension of skin paddle of a pectoralis major musculocutaneous (PMMC) flap is very small, its survival often becomes questionable. We introduce a simple technique which enlarges the practical dimension of a very small skin paddle, leading to ensure the survival of a PMMC flap.Method and ResultA PMMC flap size of 1.5 × 4 cm was required for repair of leakage which developed 2 weeks after the primary ablative surgery for hypopharyngeal cancer. The skin paddle was designed in the size of 4.5 × 7 cm and was deepithelized except the original dimension. After the skin edge was sutured to the defect margin, the deepithelized dermal portion covered the repair site to enhance the suture.ConclusionThe effective dimension of a very small skin paddle can be quite enlarged thus increasing the possibility of capturing perforators. This could decrease the risk of avulsion during flap transfer and provide backing of the repair site. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
Influence of cell culture medium composition on in vitro dissolution behavior of a fluoride‐containing bioactive glass
Authors: Shah Furqan A. , Brauer Delia S. , Wilson Rory M. , Hill Robert G. , Hing Karin A. 
Published: March 2013

AbstractBioactive glasses are used clinically for bone regeneration, and their bioactivity and cell compatibility are often characterized in vitro, using physiologically relevant test solutions. The aim of this study was to show the influence of varying medium characteristics (pH, composition, presence of proteins) on glass dissolution and apatite formation. The dissolution behavior of a fluoride‐containing bioactive glass (BG) was investigated over a period of one week in Eagle's Minimal Essential Medium with Earle's Salts (MEM), supplemented with either, (a) acetate buffer, (b) 4‐(2‐hydroxyethyl)‐1‐piperazineethanesulfonic acid (HEPES) buffer, (c) HEPES + carbonate, or (d) HEPES + carbonate + fetal bovine serum. Results show pronounced differences in pH, ion release, and apatite formation over 1 week: Despite its acidic pH (pH 5.8 after BG immersion, as compared to pH 7.4–8.3 for HEPES‐containing media), apatite formation was fastest in acetate buffered (HEPES‐free) MEM. Presence of carbonate resulted in formation of calcite (calcium carbonate). Presence of serum proteins, on the other hand, delayed apatite formation significantly. These results confirm that the composition and properties of a tissue culture medium are important factors during in vitro experiments and need to be taken into consideration when interpreting results from dissolution or cell culture studies. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 647–654, 2014.
An injectable and biodegradable hydrogel based on poly(α,β‐aspartic acid) derivatives for localized drug delivery
Authors: Lu Caicai , Wang Xiaojuan , Wu Guolin , Wang Jingjing , Wang Yinong , Gao Hui , Ma Jianbiao 
Published: March 2013

AbstractAn injectable hydrogel via hydrazone cross‐linking was prepared under mild conditions without addition of cross‐linker or catalyst. Hydrazine and aldehyde modified poly(aspartic acid)s were used as two gel precursors. Both of them are water‐soluble and biodegradable polymers with a protein‐like structure, and obtained by aminolysis reaction of polysuccinimide. The latter can be prepared by thermal polycondensation of aspartic acid. Hydrogels were prepared in PBS solution and characterized by different methods including gel content and swelling, Fourier transformed‐infrared spectroscopy, and in vitro degradation experiment. A scanning electron microscope viewed the interior morphology of the obtained hydrogels, which showed porous three‐dimensional structures. Different porous sizes were present, which could be well controlled by the degree of aldehyde substitution in precursor poly(aspartic acid) derivatives. The doxorubicin‐loaded hydrogels were prepared and showed a pH‐sensitive release profile. The release rate can be accelerated by decreasing the environmental pH from a physiological to a weak acidic condition. Moreover, the cell adhesion and growth behaviors on the hydrogel were studied and the polymeric hydrogel showed good biocompatibility. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 628–638, 2014.
Bioactive substrates for human retinal pigment epithelial cell growth from elastin‐like recombinamers
Authors: Singh Amar K. , Srivastava Girish K. , Martín Laura , Alonso Matilde , Pastor J. Carlos 
Published: March 2013

AbstractThe aim of this study was to investigate the use of bioactive RGD‐containing elastin‐like recombinamers (ELR‐RGDs) as a substrate that can maintain human retinal pigment epithelial cell (hRPE) phenotype and growth pattern. Results obtained are compared with previously published behavior of ARPE19 cells. The extension of these results to hRPE is required because ARPE19 cells cannot be used clinically to treat age‐related macular degeneration. hRPE cells were isolated, cultured, seeded, and grown on surface of glass, treated polystyrene (TCP), and solvent‐cast ELR‐RGD and ELR‐IK film with no specific sequence. Cells were analyzed to study cell adhesion, proliferation, morphology, and RPE65 protein expression by staining with diamidino‐2‐phenylindole, Rhodamine‐Phalloidin, and anti‐RPE65 antibody at 12, 24, 72, 120, 168, and 360 h. hRPE cells always grew better on ELR‐RGD than on glass and ELR‐IK but not on TCP. The kinetic hRPE growth curves confirmed that growth differences started to appear at 24 h for these surfaces in ascending order of cell growths, namely glass, ELR‐IK, ELR‐RGD, and TCP. There was a clear difference at 360 h. ELR‐RGD maintained hRPE cells stable morphology and RPE65 protein expression. ELR‐RGD seems to be a good substrate for growing hRPE cells with stable morphology and RPE65 protein expression. As such, this work confirms our hypothesis regarding ELR‐RGD substrates viability, which can be used as a Bruch's membrane prosthesis for further studies in animals. However, these results must subsequently be extrapolated to use of hRPE cells in animals to evaluate them as a transplantation vehicle in human. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 639–646, 2014.