Managing Disease-Modifying Antirheumatic Drugs (DMARDs) for Patients Undergoing Elective Spine Surgery: A Pilot Survey.

Introduction: Patients affected by autoimmune pathologies such as rheumatoid arthritis require surgery for various reasons. However, the systemic inflammatory nature of these disease processes often necessitates therapy with disease-modifying antirheumatic drugs (DMARDs). Alteration of these agents in the perioperative period for surgery requires a careful risk-benefit analysis to limit disease flares, infection rates, and secondary revisions. We therefore queried North and South American practices for perioperative management of DMARDs in patients undergoing elective spine surgery. Methods: An institutional review board-approved pilot survey was disseminated to spine surgeons regarding how they managed DMARDs before, during, and after spine surgery. Results: A total of 47 spine surgeons responded to the survey, 37 of whom were neurosurgeons (78.7%) and 10 orthopedic surgeons (21.3%). Of the respondents, 80.9% were from North America, 72.3% were board-certified, 51.1% practiced in academic institutions, and 66.0% performed 50-150 spine surgeries per year. Most respondents consulted a rheumatologist before continuing or withholding a DMARD in the perioperative period (70.2%). As such, a majority of the spine surgeons in this survey withheld DMARDs at an average of 13.8 days before and 19.6 days after spine surgery. Of the spine surgeons who withheld DMARDs before and after spine surgery, the responses were variable with a trend toward no increased risk of postoperative complications. Conclusions: Based on the results of this pilot survey, we found a consensus among spine surgeons to withhold DMARDs before and after elective spine surgery.

Outcome differences between males and females undergoing deep brain stimulation for treatment-resistant depression: systematic review and individual patient data meta-analysis.

BACKGROUND: Treatment-resistant depression (TRD) occurs more commonly in women. Deep brain stimulation (DBS) is an emerging treatment for TRD, and its efficacy continues to be explored. However, differences in treatment outcomes between males and females have yet to be explored in formal analysis. METHODS: A PRISMA-compliant systematic review of DBS for TRD studies was conducted. Patient-level data were independently extracted by two authors. Treatment response was defined as a 50 % or greater reduction in depression score. Percent change in depression scores by gender were evaluated using random-effects analyses. RESULTS: Of 737 records, 19 studies (129 patients) met inclusion criteria. The mean reduction in depression score for females was 57.7 % (95 % CI, 64.33 %-51.13 %), whereas for males it was 35.2 % (95 % CI, 45.12 %-25.23 %) (p < 0.0001). Females were more likely to respond to DBS for TRD when compared to males (OR = 2.44, 95 % CI 1.06, 1.95). These differences varied in significance when stratified by DBS anatomical target, age, and timeframe for responder classification. LIMITATIONS: Studies included were open-label trials with small sample sizes. CONCLUSIONS: Our findings suggest that females with TRD respond at higher rates to DBS treatment than males. Further research is needed to elucidate the implications of these results, which may include connectomic sexual dimorphism, depression phenotype variations, or unrecognized symptom reporting differences. Methodological standardization of outcome scales, granular demographic data, and individual subject outcomes would allow for more robust comparisons between trials.

Subdural hematoma, retinal hemorrhage, and fracture triad as a clinical predictor for the diagnosis of child abuse.

OBJECTIVE: Nonaccidental trauma (NAT) is a major cause of traumatic death during infancy and early childhood. Several findings are known to raise the index of clinical suspicion: subdural hematoma (SDH), retinal hemorrhage (RH), fracture, and external trauma. Combinations of certain injury types, determined via statistical frequency associations, may assist clinical diagnostic tools when child abuse is suspected. The present study sought to assess the statistical validity of the clinical triad (SDH + RH + fracture) in the diagnosis of child abuse and by extension pediatric NAT. METHODS: A retrospective review of The University of Arizona Trauma Database was performed. All patients were evaluated for the presence or absence of the components of the clinical triad according to specific International Classification of Diseases (ICD)-10 codes. Injury type combinations included some variation of SDH, RH, all fractures, noncranial fracture, and cranial fracture. Each injury type was then correlated with the ICD-10 codes for child abuse or injury comment keywords. Statistical analysis via contingency tables was then conducted for test characteristics such as sensitivity, specificity, positive predictive value, and negative predictive value. RESULTS: There were 3149 patients younger than 18 years of age included in the quantitative analysis, all of whom had at least one component of the clinical triad. From these, 372 patients (11.8%) had a diagnosis of child abuse. When compared to a single diagnosis of either SDH, RH, all fractures, noncranial fracture, or cranial fracture, the clinical triad had a significantly greater correlation with the diagnosis of child abuse (100% of cases) (p < 0.0001). The dyad of SDH + RH also had a significantly greater correlation with a child abuse diagnosis compared to single diagnoses (88.9%) (p < 0.0001). The clinical triad of SDH + RH + fracture had a sensitivity of 88.8% (95% CI 87.6%-89.9%), specificity of 100% (95% CI 83.9%-100%), and positive predictive value of 100% (95% CI 99.9%-100%). The dyad of SDH + RH had a sensitivity of 89.1% (95% CI 87.9%-90.1%), specificity of 88.9% (95% CI 74.7%-95.6%), and positive predictive value of 99.9% (95% CI 99.6%-100%). All patients with the clinical triad were younger than 3 years of age. CONCLUSIONS: When SDH, RH, and fracture were present together, child abuse and by extension pediatric NAT were highly likely to have occurred.

Evaluation of the Thoracolumbar Injury Classification and Severity (TLICS) Score Over a Two-Year Period at a Level One Trauma Center.

Introduction The use of the Thoracolumbar Injury Classification and Severity Score (TLICS) and other classification systems for guiding the management of traumatic spinal injuries remains controversial. TLICS is one of the few classifications that provides treatment recommendations.We sought to analyze intervention modality selection based on the TLICS scoring system. Methods A retrospective review of patients presenting with traumatic thoracolumbar fractures at a level 1 trauma center over a two-year period was performed. Primary endpoints for comparison analysis included visual analog scale (VAS) scores and Cobb angles during follow-up. Results There were 272 patients with thoracolumbar fractures, of whom 212 had TLICS of ≤3, six with TLICS of 4, and 54 with TLICS of ≥5. Of the 272 total patients, 59 were treated via surgery and 213 via non-surgical conservative methods. The VAS scores significantly decreased from presentation to last follow-up in both surgically treated and conservative groups (p<0.0001). This remained consistent in subgroup analyses of TLICS ≤ 3, TLICS = 4, and TLICS ≥ 5 (p<0.0001). Burst fractures treated conservatively had larger fracture Cobb angles versus those treated via surgery at the last follow-up, although this was not significantly associated (p=0.07). The only significant relationship with Cobb angles was in distraction fractures of the TLICS > 4 conservative group, who had significantly lower Cobb angles at the last follow-up than the TLICS > 4 surgical group (p<0.04). The "surgeon's choice" for TLICS = 4 was surgical intervention (4/6 patients, 66.7%). Conclusion Using the TLICS score, thoracolumbar injuries in a level 1 trauma center are more commonly TLICS ≤ 3. For patients with TLICS = 4, the surgeon's choice was most commonly surgical repair. VAS scores decreased over time from presentation between surgically and conservatively managed patients (as well as within-group analyses). The data concerning Cobb angles were more ambiguous, as larger Cobb angles in burst fractures treated conservatively did not show statistically significant differences with surgery.

Predictors of revision surgery after bedside subdural drain placement for chronic subdural hematomas.

BACKGROUND AND OBJECTIVE: For chronic subdural hematoma (cSDH), bedside subdural drains (SDD) provide a useful alternative to more invasive neurosurgical techniques, including evacuation through multiple burr holes or formal craniotomy. However, no scale currently exists adequately predicting SDD candidacy or treatment response. The present study sought to characterize predictors of revision surgery after initial treatment with bedside SDD for cSDH. METHODS: We conducted a retrospective case control study of cSDH patients treated with bedside SDD at a level one trauma center between 2018 and 2022. Binomial regression was used to compare SDD patients and generate odds ratios associated with revision surgery, which were compared using a binary random effects model. RESULTS: Ninety six cSDH patients were included, of whom 13 (13.5%) required a revision surgery after initial treatment failure with bedside SDD. Patients requiring revision surgery demonstrated an increased male predominance (84.6% vs. 69.9% of SDD patients not requiring revision surgery), tended to be younger (67.8 vs. 70.5 years) with a greater body mass index (28.7 vs. 25.6 kg/m2), and have a lower Glasgow Coma Scale (GCS) score on presentation of 12.5 (versus 14). Patients with an initial GCS score less than 13 (OR 11.0 95% CI 2.8 - 43.3), midline shift greater than 10 mm on CT (OR 6.5 95% CI 1.7 - 25.7), or duration of SDD placement longer than 3 days (OR 10.5 95% CI 2.6 - 41.9) demonstrated a greater likelihood of needing a revision surgery after initial treatment with bedside SDD. CONCLUSION: Among patients treated with SDD, we identified 3 independent factors predicting the need for revision surgery: GCS score, midline shift, and duration of drain placement. Craniotomy may be favored over bedside SDD in patients presenting with a GCS score less than 13 or midline shift greater than 10 mm and for SDD patients demonstrating inadequate clinical response after 3 days.

Procedure-Related Complications in Sham Surgeries for Parkinson's Clinical Trials: A Meta-analysis.

BACKGROUND: Double-blind, sham-controlled neurosurgical trials for neurodegenerative disorders are debated as an ethical dilemma, particularly regarding subjects randomized to the sham surgery group with general anesthesia. OBJECTIVE: The objective of this study was to examine the safety of sham surgeries in Parkinson's disease (PD) clinical trials through complications related to the procedure. METHODS: A systematic review and meta-analysis were performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Rates and odds ratios (OR) were compared using random effects analysis. RESULTS: Seven studies, all randomized, double-blind, sham surgery-controlled trials, with 309 patients with PD, were qualitatively and quantitatively analyzed: 141 patients in sham groups and 168 patients in the experimental arms of gene or cell therapy trials. Sham subjects had lower rates of gastrointestinal, positioning, incision-site, respiratory (hypoxic or hypercapnic respiratory failure), cardiovascular, thromboembolism, postoperative cognitive decline, skull fracture, and intracranial or spinal complications when compared with active treatment subjects. Sham subjects, however, had a higher rate of perioperative respiratory infections, such as pneumonia or sinusitis. Further, sham subjects were less likely to experience postoperative cognitive decline (OR, 0.23; 95% confidence interval [CI]: 0.11-0.47), intracranial or spinal complications (OR, 0.10; 95% CI: 0.01-0.75), total major morbidity (OR, 0.30; 95% CI: 0.19-0.47), or overall complications (OR, 0.59; 95% CI: 0.47-0.75) when compared with patients receiving experimental therapy. CONCLUSIONS: Patients with PD in the sham surgery control arm of cell transplantation or gene therapy clinical trials have a low risk of procedure-related adverse events overall and fewer complications than patients in the experimental groups. There were no reported deaths attributed to sham surgery-controlled PD clinical trials. © 2023 International Parkinson and Movement Disorder Society.

RON-augmented cholesterol biosynthesis in breast cancer metastatic progression and recurrence.

Recurrence remains a significant clinical barrier to improving breast cancer patient outcomes. The RON receptor is a predictor of metastatic progression and recurrence in breast cancers of all subtypes. RON directed therapies are in development, but preclinical data directly testing the impact of RON inhibition on metastatic progression/recurrence are lacking, and mechanisms to exert this function remain unclear. Herein, we modeled breast cancer recurrence using implantation of RON-overexpressing murine breast cancer cells. Recurrent growth was examined after tumor resection via in vivo imaging and ex vivo culture of circulating tumor cells from whole blood samples from tumor bearing mice. In vitro functional assessment of was performed using mammosphere formation assays. Transcriptomic pathway enrichment identified glycolysis and cholesterol biosynthesis pathways, transcription factor targets, and signaling pathways enriched in RON-overexpressing breast cancer cells. BMS777607, a RON inhibitor, abrogated CTC colony formation tumor cells and tumor recurrence. RON promoted mammosphere formation through upregulated cholesterol production that utilizes glycolysis-derived substrates. In mouse models with RON overexpression, statin-mediated inhibition of cholesterol biosynthesis impeded metastatic progression and recurrence but does not affect the primary tumor. RON upregulates glycolysis and cholesterol biosynthesis gene expression by two pathways: MAPK-dependent c-Myc expression and ß-catenin -dependent SREBP2 expression.

An Introduction and Overview of RON Receptor Tyrosine Kinase Signaling.

RON is a receptor tyrosine kinase (RTK) of the MET receptor family that is canonically involved in mediating growth and inflammatory signaling. RON is expressed at low levels in a variety of tissues, but its overexpression and activation have been associated with malignancies in multiple tissue types and worse patient outcomes. RON and its ligand HGFL demonstrate cross-talk with other growth receptors and, consequentially, positions RON at the intersection of numerous tumorigenic signaling programs. For this reason, RON is an attractive therapeutic target in cancer research. A better understanding of homeostatic and oncogenic RON activity serves to enhance clinical insights in treating RON-expressing cancers.

Imaging of pediatric thyroid tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper.

Pediatric thyroid cancer is rare in children; however, incidence is increasing. Papillary thyroid cancer and follicular thyroid cancer are the most common subtypes, comprising about 90% and 10% of cases, respectively. This paper provides consensus imaging recommendations for evaluation of pediatric patients with thyroid cancer at diagnosis and during follow-up.

Medical School Interview Preference in the Post-COVID-19 Era: A Single Institution Experience.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic presented unforeseen obstacles to prospective medical students such as Medical College of Admission Test (MCAT) scheduling postponements and technical challenges during virtual interviews. Students were also faced with difficult decisions post-submission such as having to choose a program without ever visiting a school in person. The primary objective of the present study is to assess the changes in medical school interview preferences and experiences in the post-COVID-19 era. METHODS: A retrospective survey of the class of 2024 (in-person interview group) and class of 2025 (virtual interview group) at an allopathic medical school was conducted in the Fall of 2021 via the Qualtrics XM online survey software (Qualtrics, Provo, UT, USA). RESULTS: There were 195 survey respondents: 77 students from the in-person interview group and 89 students from the virtual group. More students in the virtual cohort had to reschedule their MCAT compared to the in-person cohort (56.1% versus 14.3%; p<0.001). The in-person group had higher travel-related expenses (>$500) compared to the group who interviewed virtually (65.1% versus 2.4%; p<0.001). More students from the in-person cohort preferred the in-person interview format compared to the virtual cohort (85.7% versus 22.5%; p<0.001). Lastly, 87% of the in-person group and 24.7% of the virtual group felt they were able to gather a clear impression of the atmosphere and culture of a school from the interview trail alone (p<0.001). CONCLUSION: Matriculated medical students at an allopathic medical school who applied during the COVID-19 pandemic had more pre-application hurdles when compared to the cohort who applied just prior to the pandemic. Students who primarily had virtual interviews during the pandemic had less travel-related costs but felt more limited in their experience of a school's culture and ability to establish rapport with interviewers. Despite this, however, the virtual group still expressed a preference for virtual interviews.

RON (MST1R) and HGFL (MST1) Co-Overexpression Supports Breast Tumorigenesis through Autocrine and Paracrine Cellular Crosstalk.

BACKGROUND: Aberrant RON signaling is present in numerous cancers including breast cancer. Evidence suggests that the ligand, hepatocyte growth factor-like (HGFL), is also overexpressed in breast cancer. RON (MST1R) and HGFL (MST1) genes are located on human chromosome 3 and mouse chromosome 9 respectively and are found near each other in both species. Based on co-expression patterns, we posited that RON and HGFL are co-regulated and that coordinate upregulation drives aggressive tumorigenesis. METHODS: Mouse models were used to establish the functional significance of RON and HGFL co-overexpression on the activation of tumor cells and tumor-associated macrophages in breast cancer. TCGA and METABRIC gene expression and alteration data were used to query the relationships between MST1R and MST1 in breast cancer. RESULTS: In tumor models, physiologic sources of HGFL modestly improve Arginase-1+ (M2) macrophage recruitment to the tumor proper. Tumor-cell produced HGFL functions in autocrine to sustain tumor cell RON activation and MAPK-dependent secretion of chemotactic factors and in paracrine to activate RON on macrophages and to promote breast cancer stem cell self-renewal. In silico analyses support that RON and HGFL are co-expressed across virtually all cancer types including breast cancer and that common genomic alterations do not appear to be drivers of RON/HGFL co-overexpression. CONCLUSIONS: Co-overexpression of RON and HGFL in breast cancer cells (augmented by physiologic sources of HGFL) promotes tumorigenesis through autocrine-mediated RON activation/RON-dependent secretome changes and paracrine activation of macrophage RON to promote breast cancer stem cell self-renewal.

Perioperative management of disease-modifying antirheumatic drugs for patients undergoing elective spine surgery: a systematic review.

BACKGROUND: In preparation for surgery, patients being treated with disease-modifying antirheumatic drugs (DMARDs) are recommended to either continue or withhold therapy perioperatively. Some of these drugs have known effects against bone healing, hence the importance of adequately managing them before and after surgery. OBJECTIVE: We aim to assess the current evidence for managing conventional synthetic and/or biologic DMARDs in the perioperative period for elective spine surgery. METHODS: A systematic review of four databases was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The included manuscripts were methodically scrutinized for quality, postoperative infections, wound healing characteristics, bone fusion rates, and clinical outcomes. RESULTS: Six studies were identified describing the management of conventional synthetic and/or biologic DMARDs. There were 294 DMARD-treated patients described undergoing various spine surgeries such as craniovertebral junction fusions. Three of the studies involved exclusive continuation of DMARDs in the perioperative window; one study involved exclusive discontinuation of DMARDs in the perioperative window; and two studies involved continuation or discontinuation of DMARDs perioperatively. Of patients that continued DMARDs in the perioperative period, 13/50 patients (26.0%) had postoperative surgical site infections or wound dehiscence, 2/19 patients (10.5%) had delayed wound healing, and 32/213 patients (15.0%) had secondary revision surgeries. A fusion rate of 14/19 (73.6%) was described in only one study for patients continuing DMARDs perioperatively. CONCLUSIONS: The available published data may suggest a higher risk of wound healing concerns and lower than average bone fusion, although this may be under-reported given the current state of the literature.

Complete seizure-free rates following interventional treatment of intracranial arteriovenous malformations: a systematic review and meta-analysis.

Seizures are common presenting symptoms of intracranial arteriovenous malformations (AVMs). This systematic review and meta-analysis aims to assess the current evidence regarding complete seizure freedom rates following surgical resection, stereotactic radiosurgery (SRS), and/or endovascular embolization of intracranial AVMs. A systematic review of PubMed, Ovid MEDLINE, and Ovid EMBASE was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Included manuscripts were methodically scrutinized for quality, spontaneous AVM-associated or hemorrhage-associated seizures, complete seizure-free rates following each interventional treatment, follow-up duration; determination methods of seizure outcomes, and average time-to-onset of recurrent seizures after each treatment. Manuscripts that described patients with nondisabling seizures or reduced seizure frequency in their seizure-free calculations were excluded. Seizure freedom rates following surgical resection, SRS, and endovascular embolization were compared via random-effect analysis. Thirty-four studies with a total of 1765 intracranial AVM patients presenting with spontaneous AVM-associated seizures and 408 patients presenting with hemorrhage-associated seizures were qualitatively analyzed. For patients presenting with AVM-associated seizures, the complete seizure-free rates were 73.0% (321/440 patients; 95% CI 68.8-77.1%) following surgical resection, 60.5% (376/622 patients; 95% CI 56.6-64.3%) following SRS, and 44.6% (29/65 patients; 95% CI 32.5-56.7%) following endovascular embolization alone. For patients presenting with either AVM-associated or hemorrhage-associated seizures, the complete seizure-free rates were 73.0% (584/800 patients; 95% CI 69.9-76.1%) following surgical resection, 46.4% (572/1233 patients; 95% CI 43.6-49.2%) following SRS, and 44.6% (29/65 patients; 95% CI 32.5-56.7%) following embolization. For patients presenting with either AVM-associated or hemorrhage-associated seizures, the overall improvements in seizure outcomes regardless of complete seizure freedom were 82.6% (661/800 patients; 95% CI 80.0-85.3%), 70.6% (870/1233 patients; 95% CI 68.0-73.1%), and 70.8% (46/65 patients; 95% CI 59.7-81.1%) following surgical resection, SRS, and embolization, respectively. No study reported information about the time-to-onset for recurrent seizures in any patient following treatment, as seizure outcomes were only described at the last follow-up visit. The available data suggests that surgical resection results in the highest rate of complete seizure freedom. The rate of seizure improvement following surgery increased further to 82.3% when including patients who had improved seizure frequency without achieving true seizure freedom. Complete seizure-free rates following SRS or embolization were more ambiguous and lower when compared to surgical resection. There is a need for high quality studies evaluating AVM treatment modalities and clearly defined seizure outcomes, as the current literature consists mostly of heterogenous patient populations.

Pilot study for comparative assessment of dual-energy computed tomography and single-photon emission computed tomography V/Q scanning for lung perfusion evaluation in infants.

OBJECTIVE: To evaluate clinical applications of dual-energy computed tomography (DECT) in pediatric-specific lung diseases and compare ventilation and perfusion findings with those from single-photon emission computed tomography (SPECT-CT) V/Q. METHODS: All patients at our institution who underwent exams using both techniques within a 3-month period were included in this study. Two readers independently described findings for DECT, and two other readers independently analyzed the SPECT-CT V/Q scan data. All findings were compared between readers and disagreements were reassessed and resolved by consensus. Inter-modality agreements are described throughout this study. RESULTS: Eight patients were included for evaluation. The median age for DECT scanning was 3.5 months (IQR = 2). Five of these patients were scanned for both DECT and SPECT-CT V/Q studies the same day, and three had a time gap of 7, 65, and 94 days between studies. The most common indications were chronic lung disease (5/8; 63%) and pulmonary hypertension (6/8; 75%). DECT and SPECT-CT V/Q identified perfusion abnormalities in concordant lobes in most patients (7/8; 88%). In one case, atelectasis limited DECT perfusion assessment. Three patients ultimately underwent lobectomy with corresponding perfusion abnormalities identified by all reviewers on both DECT and SPECT-CT V/Q in all resected lobes. CONCLUSION: DECT is a feasible technique that could be considered as an alternative for SPECT-CT V/Q for lung perfusion evaluation in infants.

Contrast-enhanced ultrasound of liver lesions in children.

Initial pediatric imaging of the liver heavily relies on ultrasonography (US) because it is free of ionizing radiation, easily portable and readily available. Although conventional US (gray-scale and color Doppler) is often an excellent screening tool, its relative low specificity compared to CT/MRI limits liver lesion characterization. The United States Food and Drug Administration's recent approval of an intravenous US contrast agent for pediatric liver lesion characterization (sulfur hexafluoride lipid-type A microspheres) and its excellent safety profile have spurred increased interest in contrast-enhanced US for definitive diagnosis of pediatric liver lesions. This review focuses on the safety of contrast-enhanced US, role of contrast-enhanced US in the evaluation of focal liver lesions, basic contrast-enhanced US technique for liver imaging, and interpretation principles. The authors review common focal liver lesions, with special attention to the role of contrast-enhanced US in the pediatric oncology population.

Analysis of novel domain-specific mutations in the zebrafish ndr2/cyclops gene generated using CRISPR-Cas9 RNPs.

Nodal-related protein (ndr2) is amember of the transforming growth factor type ß superfamily of factors and is required for ventral midline patterning of the embryonic central nervous system in zebrafish. In humans, mutations in the gene encoding nodal cause holoprosencephaly and heterotaxy. Mutations in the ndr2 gene in the zebrafish (Danio rerio) lead to similar phenotypes, including loss of the medial floor plate, severe deficits in ventral forebrain development and cyclopia. Alleles of the ndr2 gene have been useful in studying patterning of ventral structures of the central nervous system. Fifteen different ndr2 alleles have been reported in zebrafish, of which eight were generated using chemical mutagenesis, four were radiation-induced and the remaining alleles were obtained via random insertion, gene targeting (TALEN) or unknown methods. Therefore, most mutation sites were random and could not be predicted a priori. Using the CRISPR-Cas9 system from Streptococcus pyogenes, we targeted distinct regions in all three exons of zebrafish ndr2 and observed cyclopia in the injected (G0) embryos.We show that the use of sgRNA-Cas9 ribonucleoprotein (RNP) complexes can cause penetrant cyclopic phenotypes in injected (G0) embryos. Targeted polymerase chain reaction amplicon analysis using Sanger sequencing showed that most of the alleles had small indels resulting in frameshifts. The sequence information correlates with the loss of ndr2 activity. In this study, we validate multiple CRISPR targets using an in vitro nuclease assay and in vivo analysis using embryos. We describe one specific mutant allele resulting in the loss of conserved terminal cysteine-coding sequences. This study is another demonstration of the utility of the CRISPR-Cas9 system in generating domain-specific mutations and provides further insights into the structure-function of the ndr2 gene.

18F-FDG Uptake During Early Adjuvant Chemotherapy Predicts Histologic Response in Pediatric and Young Adult Patients with Osteosarcoma.

The purpose of this study was to determine the relationship of 18F-FDG uptake in the primary tumor at diagnosis, during therapy, and after therapy with a histologic response and event-free survival in pediatric and young adult patients with osteosarcoma (OS). Methods: Serial (baseline and 5 and 10 wk after start of therapy) 18F-FDG PET/CT imaging was performed in patients with newly diagnosed OS treated uniformly in a therapeutic trial at a single institution. Whole-body images were obtained approximately 1 h after injection of 18F-FDG. Logistic regression was used to study the association of tumor uptake and changes in SUVmax between 0, 5, and 10 wk for both clinical endpoints. Results: Thirty-four patients (17 males; median age, 12.2 y; age range, 6.8-19.1 y) underwent PET imaging; 25 (74%) had localized disease. Primary tumor locations included the femur (n = 17; 50%), tibia (n = 9; 26%), and humerus (n = 5; 15%). Logistic regression showed that SUVmax at 5 wk (P = 0.034) and 10 wk (P = 0.022) and percentage change from baseline at 10 wk (P = 0.021) were highly predictive of a histologic response. Using SUVmax of 4.04 at week 5, SUVmax of 3.15 at week 10, and 60% decrease from baseline at week 10 as cutoff values, we determined that the respective sensitivities were 0.93, 0.93, and 0.79 and that the respective specificities were 0.53, 0.71, and 0.76. Conclusion: SUVmax on routine images at 5 or 10 wk and percentage change in SUVmax from baseline to week 10 were metabolic predictors of a histologic response in OS. These findings may be useful in the early identification of patients who are responding poorly to therapy and may benefit from a change in treatment.

Evaluation of the biodistribution of 11C-methionine in children and young adults.

UNLABELLED: The purpose of this study was to evaluate the biodistribution of (11)C-labeled methionine in non-tumor-involved organs in pediatric patients studied for malignant diseases. METHODS: Ninety-three children and young adults with known or suspected malignancies underwent (11)C-methionine PET and CT scans. Imaging began 5-15 min after injection of 740 MBq (20 mCi) per 1.7 m(2) of body surface area. Images were acquired from the top of the head through the mid thighs. Standardized uptake values were determined using regions of interest drawn on the CT image and transferred to the corresponding transverse PET slice. RESULTS: The highest concentrations of (11)C-methionine were found in the pancreas and liver. Less intense uptake was seen in other regions, such as the salivary glands, tonsils, and bone marrow. There was little uptake in the lungs, fat (including brown adipose tissue), and muscle. Uptake in bone marrow, parotid glands, and tonsils was slightly but statistically significantly higher in men than women. Testicular, bone marrow, and left ventricular uptake increased with age. There was little variability statistically between comparisons of uptake change and groupings of age, race, sex, and patients studied at the time of diagnosis versus previously treated patients. CONCLUSION: High uptake of (11)C-methionine is reliably found in the pancreas and liver, consistent with the anabolic functions of these organs. Low uptake in the brain, neck, chest, pelvis, and extremities will facilitate tumor localization in those areas. However, intense uptake in the upper abdomen may limit the diagnostic utility of (11)C-methionine in that area.

Expression of transient receptor potential (TRP) channel mRNAs in the mouse olfactory bulb.

Transient receptor potential (TRP) channels are a large family of cation channels. The 28 TRP channel subtypes in rodent are divided into 6 subfamilies: TRPC1-7, TRPV1-6, TRPM1-8, TRPP2/3/5, TRPML1-3 and TRPA1. TRP channels are involved in peripheral olfactory transduction. Several TRPC channels are expressed in unidentified neurons in the main olfactory bulb (OB), but the expression of most TRP channels in the OB has not been investigated. The present study employed RT-PCR as an initial survey of the expression of TRP channel mRNAs in the mouse OB and in 3 cell types: external tufted, mitral and granule cells. All TRP channel mRNAs except TRPV5 were detected in OB tissue. Single cell RT-PCR revealed that external tufted, mitral and granule cell populations expressed in aggregate 14 TRP channel mRNAs encompassing members of all 6 subfamilies. These different OB neuron populations expressed 7-12 channel mRNAs. Common channel expression was more similar among external tufted and mitral cells than among these cells and granule cells. These results indicate that a large number of TRP channel subtypes are expressed in OB neurons, providing the molecular bases for these channels to regulate OB neuron activity and central olfactory processing.

Biocompatibility of polymer grafted core/shell iron/carbon nanoparticles.

For biomedical applications, emerging nanostructures requires stringent evaluations for their biocompatibility. Core/shell iron/carbon nanoparticles (Fe@CNPs) are nanomaterials that have potential applications in magnetic resonance imaging (MRI), magnetic hyperthermia and drug delivery. However, their interactions with biological systems are totally unknown. To evaluate their potential cellular perturbations and explore the relationships between their biocompatibility and surface chemistry, we synthesized polymer grafted Fe@CNPs with diverse chemistry modifications on surface and investigated their dynamic cellular responses, cell uptake, oxidative stress and their effects on cell apoptosis and cell cycle. The results show that biocompatibility of Fe@CNPs is both surface chemistry dependent and cell type specific. Except for the carboxyl modified Fe@CNPs, all other Fe@CNPs present low toxicity and can be used for further functionalization and in a wide range of biomedical applications.