Abdominal fellowship-trained versus generalist radiologist accuracy when interpreting MR and CT for the diagnosis of appendicitis.

OBJECTIVES: To compare the diagnostic accuracy of generalist radiologists working in a community setting against abdominal radiologists working in an academic setting for the interpretation of MR when diagnosing acute appendicitis among emergency department patients. METHODS: This observational study examined MR image interpretation (non-contrast MR with diffusion-weighted imaging and intravenous contrast-enhanced MR) from a prospectively enrolled cohort at an academic hospital over 18 months. Eligible patients had an abdominopelvic CT ordered to evaluate for appendicitis and were > 11 years old. The reference standard was a combination of surgery and pathology results, phone follow-up, and chart review. Six radiologists blinded to clinical information, three each from community and academic practices, independently interpreted MR and CT images in random order. We calculated test characteristics for both individual and group (consensus) diagnostic accuracy then performed Chi-square tests to identify any differences between the subgroups. RESULTS: Analysis included 198 patients (114 women) with a mean age of 31.6 years and an appendicitis prevalence of 32.3%. For generalist radiologists, the sensitivity and specificity (95% confidence interval) were 93.8% (84.6-98.0%) and 88.8% (82.2-93.2%) for MR and 96.9% (88.7-99.8%) and 91.8% (85.8-95.5%) for CT. For fellowship-trained radiologists, the sensitivity and specificity were 96.9% (88.2-99.5%) and 89.6% (82.8-94%) for MR and 98.4% (90.5-99.9%) and 93.3% (87.3-96.7%) for CT. No statistically significant differences were detected between radiologist groups (p = 1.0, p = 0.53, respectively) or when comparing MR to CT (p = 0.21, p = 0.17, respectively). CONCLUSIONS: MR is a reliable, radiation-free imaging alternative to CT for the evaluation of appendicitis in community-based generalist radiology practices. KEY POINTS: • There was no significant difference in MR image interpretation accuracy between generalist and abdominal fellowship-trained radiologists when evaluating sensitivity (p = 1.0) and specificity (p = 0.53). • There was no significant difference in accuracy comparing MR to CT imaging for diagnosing appendicitis for either sensitivity (p = 0.21) or specificity (p = 0.17). • With experience, generalist radiologists enhanced their MR interpretation accuracy as demonstrated by improved interpretation sensitivity (OR 2.89 CI 1.44-5.77, p = 0.003) and decreased mean interpretation time (5 to 3.89 min).

Real-world experience with intravaginal culture using INVOCELL: an alternative model for infertility treatment.

OBJECTIVE: To describe the current practice indications, methodology, and outcomes from a real-world experience of intravaginal culture (IVC) using INVOCELL. DESIGN: A descriptive study outlining real-world experience with INVOCELL that addresses patient selection, ovarian stimulation, embryology laboratory practices, and outcomes. SETTING: Five fertility centers in Missouri, Texas, North Carolina, South Carolina, and Virginia. PATIENTS: Four hundred sixty-three patients undergoing 526 cycles. INTERVENTION: IVC using INVOCELL. MAIN OUTCOME MEASURES: Cumulative pregnancy rate and live births. Secondary outcomes of interest included percent good quality embryos. RESULTS: IVC with INVOCELL was primarily used in women <38 years with anti-Mullerian hormone level >0.8 ng/mL. The mean numbers of retrieved oocytes ranged from 9.2 to 16. Mean numbers of oocytes and sperm-injected oocytes loaded per INVOCELL ranged from a mean of 6.4-9.5 with a reported maximum of 34 oocytes loaded into the device. Most (95%) of the embryos were transferred on day 5. The mean blastocyst recovery per oocyte loaded into the device ranged from 19% to 34%; mean cumulative live birth plus ongoing pregnancy rates ranged from 29% to 53% per cycle start and 40% to 61% per transfer. CONCLUSIONS: This study of IVC using INVOCELL as an alternative model for infertility treatment confirms its utility as a viable alternative to standard incubator-based in vitro fertilization. The technology is compatible within the current framework of practice patterns and, when appropriately used, results in acceptable blastocyst recovery and live birth rates. Further use of INVOCELL in other clinical situations is warranted.

Randomized, assessor-blinded trial comparing highly purified human menotropin and recombinant follicle-stimulating hormone in high responders undergoing intracytoplasmic sperm injection.

OBJECTIVE: To evaluate the efficacy and safety of highly purified human menotropin (HP-hMG) and recombinant follicle-stimulating hormone (rFSH) for controlled ovarian stimulation in a population of patients predicted to be high responders. DESIGN: Randomized, open-label, assessor-blinded, parallel-group, noninferiority trial. SETTING: Fertility centers. PATIENT(S): A total of 620 women with serum antimüllerian hormone (AMH) ≥5 ng/mL. INTERVENTION(S): Controlled ovarian stimulation with HP-hMG or rFSH in a GnRH antagonist assisted reproductive technology (ART) cycle. Fresh transfer of a single blastocyst was performed unless ovarian response was excessive, in which all embryos were cryopreserved. Subjects could undergo subsequent frozen blastocyst transfer within 6 months of randomization. MAIN OUTCOME MEASURE(S): Ongoing pregnancy rate (OPR) after fresh transfer (primary endpoint), as well as cumulative live birth, ovarian hyperstimulation syndrome (OHSS), and pregnancy loss rates. RESULTS: OPR/cycle start after fresh transfer was 35.5% with HP-hMG and 30.7% with rFSH (difference: 4.7%, 95% CI -2.7%, 12.1%); noninferiority was established. Compared to rFSH, HP-hMG was associated with significantly lower OHSS (21.4% vs. 9.7% respectively; difference: -11.7%, 95% CI -17.3%, -6.1%) and cumulative early pregnancy loss rates (25.5% vs. 14.5% respectively; difference: -11.0%, 95% CI -18.8%, -3.14%). Despite 43 more transfers in the rFSH group, cumulative live birth rates were similar with HP-hMG and rFSH at 50.6% and 51.5% respectively (difference: -0.8%, 95% CI -8.7%, 7.1%). CONCLUSION(S): In high responders, HP-hMG provided comparable efficacy to rFSH with fewer adverse events, including pregnancy loss, suggesting its optimized risk/benefit profile in this population. CLINICAL TRIAL REGISTRATION NUMBER: NCT02554279 (clinicaltrials.gov).

Advancing precision medicine with personalized drug screening.

Personalized drug screening (PDS) of approved drug libraries enables rapid development of specific small-molecule therapies for individual patients. With a multidisciplinary team including clinicians, researchers, ethicists, informaticians and regulatory professionals, patient treatment can be optimized with greater efficacy and fewer adverse effects by using PDS as an approach to find remedies. In addition, PDS has the potential to rapidly identify therapeutics for a patient suffering from a disease without an existing therapy. From cancer to bacterial infections, we review specific maladies addressed with PDS campaigns. We predict that PDS combined with personal genomic analyses will contribute to the development of future precision medicine endeavors.

Differentiation of human and murine induced pluripotent stem cells to microglia-like cells.

Microglia are resident inflammatory cells of the CNS and have important roles in development, homeostasis and a variety of neurologic and psychiatric diseases. Difficulties in procuring human microglia have limited their study and hampered the clinical translation of microglia-based treatments shown to be effective in animal disease models. Here we report the differentiation of human induced pluripotent stem cells (iPSC) into microglia-like cells by exposure to defined factors and co-culture with astrocytes. These iPSC-derived microglia have the phenotype, gene expression profile and functional properties of brain-isolated microglia. Murine iPSC-derived microglia generated using a similar protocol have equivalent efficacy to primary brain-isolated microglia in treatment of murine syngeneic intracranial malignant gliomas. The ability to generate human microglia facilitates the further study of this important CNS cell type and raises the possibility of their use in personalized medicine applications.

Residual tumor volume and patient survival following reoperation for recurrent glioblastoma.

OBJECTIVES: Maximal safe tumor resection is part of the standard of care for patients with newly diagnosed glioblastoma. The role of reoperation in the care of patients with recurrent glioblastoma is less clear, and less than a quarter of patients undergo a second surgery. Previous studies have identified preoperative variables associated with the improved survival of patients following reoperation, and guidelines for the selection of patients for reoperation have been devised and validated. In this study, the authors analyzed the relative survival benefit of maximal safe tumor removal in a series of patients with recurrent glioblastoma who all underwent reoperation. METHODS: In this longitudinal study, the clinical and radiological data of 97 consecutive patients who underwent reoperation for recurrent glioblastoma were prospectively collected. Multiple regression analyses and Kaplan-Meier plotting were performed to identify pre- and postoperative clinical and radiological variables associated with increased survival following reoperation. RESULTS: The median postoperative survival of all patients following reoperation was 12.4 months (95% confidence interval [CI] 9.0-15.6 months). Multiple Cox regression analysis revealed that patients with large (> 3 cm(3)) residual tumors following reoperation had significantly decreased survival relative to those with residual tumors that were small (> 0-3 cm(3); hazard ratio [HR] = 3.10, 95% CI 1.69-5.70; p < 0.001) or radiologically absent (0 cm(3); HR = 5.82, 95% CI 2.98-11.37; p < 0.001). Large residual tumors had faster rates of subsequent regrowth than small (odds ratio [OR] = 4.22, 95% CI 1.19-14.97; p = 0.026) or radiologically absent (OR = 11.00, 95% CI 2.79-43.43; p = 0.001) residual tumors, and a faster regrowth rate was significantly associated with decreased survival (HR = 4.01, 95% CI 2.26-7.14; p < 0.001). CONCLUSIONS: The overall survival of patients with recurrent glioblastoma who underwent reoperations increased with decreasing postoperative residual tumor volumes. For patients meeting prognostic criteria for reoperation, the surgical goal should be to minimize residual tumor volume to maximize overall survival. Clinical trial registration no.: NCT00060541 ( ClinicalTrials.gov ).

Endosomolytic anionic polymer for the cytoplasmic delivery of siRNAs in localized in vivo applications.

The use of small interfering RNAs (siRNAs) to down-regulate the expression of disease-associated proteins carries significant promise for the treatment of a variety of clinical disorders. One of the main barriers to the widespread clinical use of siRNAs, however, is their entrapment and degradation within the endolysosomal pathway of target cells. Here we report the trafficking and function of PP75, a non-toxic, biodegradable, lipid membrane disruptive anionic polymer composed of phenylalanine derivatized poly(L-lysine iso-phthalamide). PP75 is readily endocytosed by cells, safely permeabilizes endolysosomes in a pH dependent manner and facilitates the transfer of co-endocytosed materials directly into the cytoplasm. The covalent attachment of siRNAs to PP75 using disulfide linkages generates conjugates that effectively traffic siRNAs to the cytoplasm of target cells both in vitro and in vivo. In a subcutaneous malignant glioma tumor model, a locally delivered PP75-stathmin siRNA conjugate decreases stathmin expression in tumor cells and, in combination with the nitrosourea chemotherapy carmustine, is highly effective at inhibiting tumor growth. PP75 may be clinically useful for the local delivery of siRNAs, in particular for the treatment of solid tumors.

Immediate titanium mesh cranioplasty for treatment of postcraniotomy infections.

OBJECTIVE: Postcraniotomy infections have generally been treated by debridement of infected tissues, disposal of the bone flap, and delayed cranioplasty several months later to repair the resulting skull defect. Debridement followed by retention of the bone flap has also been advocated. Here we propose an alternative operative strategy for the treatment of postcraniotomy infections. METHODS: Two patients presenting with clinical and radiographic signs and symptoms of postcraniotomy infections were treated by debridement, bone flap disposal, and immediate titanium mesh cranioplasty. The patients were subsequently administered antibiotics, and their clinical courses were followed. RESULTS: The patients treated in this fashion did not have recurrence of their infections during 3-year follow-up periods. CONCLUSIONS: Surgical debridement, bone flap disposal, and immediate titanium mesh cranioplasty may be a suitable option for the treatment of postcraniotomy infections. This treatment strategy facilitates the eradication of infectious sources and obviates the risks and costs associated with a second surgical procedure.

Treatment resistance mechanisms of malignant glioma tumor stem cells.

Malignant gliomas are highly lethal because of their resistance to conventional treatments. Recent evidence suggests that a minor subpopulation of cells with stem cell properties reside within these tumors. These tumor stem cells are more resistant to radiation and chemotherapies than their counterpart differentiated tumor cells and may underlie the persistence and recurrence of tumors following treatment. The various mechanisms by which tumor stem cells avoid or repair the damaging effects of cancer therapies are discussed.

Scale to predict survival after surgery for recurrent glioblastoma multiforme.

PURPOSE: Despite initial treatment with surgical resection, radiotherapy, and chemotherapy, glioblastoma multiforme (GBM) virtually always recurs. Surgery is sometimes recommended to treat recurrence. In this study, we sought to devise a preoperative scale that predicts survival after surgery for recurrent glioblastoma multiforme. PATIENTS AND METHODS: The preoperative clinical and radiographic data of 34 patients who underwent re-operation of recurrent GBM tumors were analyzed using Kaplan-Meier survival analysis and Cox proportional hazards regression modeling. The factors associated with decreased postoperative survival (P < .05) were used to devise a prognostic scale which was validated with a separate cohort of 109 patients. RESULTS: The factors associated with poor postoperative survival were: tumor involvement of prespecified eloquent/critical brain regions (P = .021), Karnofsky performance status (KPS) < or = 80 (P = .030), and tumor volume > or = 50 cm(3) (P = .048). An additive scale (range, 0 to 3 points) comprised of these three variables distinguishes patients with good (0 points), intermediate (1 to 2 points), and poor (3 points) postoperative survival (median survival, 10.8, 4.5, and 1.0 months, respectively; P < .001). The scale identified three statistically distinct groups within the validation cohort as well (median survival, 9.2, 6.3, and 1.9 months, respectively; P < .001). CONCLUSION: We devised and validated a preoperative scale that identifies patients likely to have poor, intermediate, and good relative outcomes after surgical resection of a recurrent GBM tumor. Application of this simple scale may be useful in counseling patients regarding their treatment options and in designing clinical trials.

Experimental approaches for the treatment of malignant gliomas.

Malignant gliomas, which include glioblastomas and anaplastic astrocytomas, are the most common primary tumors of the brain. Over the past 30 years, the standard treatment for these tumors has evolved to include maximal safe surgical resection, radiation therapy and temozolomide chemotherapy. While the median survival of patients with glioblastomas has improved from 6 months to 14.6 months, these tumors continue to be lethal for the vast majority of patients. There has, however, been recent substantial progress in our mechanistic understanding of tumor development and growth. The translation of these genetic, epigenetic and biochemical findings into therapies that have been tested in clinical trials is the subject of this review.

The influence of aromatic side-chains on the aqueous properties of pH-sensitive poly(L-lysine iso-phthalamide) derivatives.

The endosomal membrane has proven to be a challenging barrier for the delivery of therapeutic biomacromolecules, including DNA, siRNA and proteins, which are taken up by endosomes but cannot freely diffuse across lipid bilayers. Anionic polymers that undergo conformational changes and become membrane disruptive in low-pH environments have the potential to assist in the delivery of these biomacromolecules across the endosomal membrane to the cytosol. Such endosomolytic polymers have been synthesized through the grafting of hydrophobic side-chains to a poly(L-lysine iso-phthalamide) backbone. The phenylalanine grafted form of poly(L-lysine iso-phthalamide) has a pH-sensitive membrane disruptive profile corresponding to the pH range of maturing endosomes and, thus, has a favourable endosomolytic profile. In order to understand the influence of hydrophobicity versus pi-pi interactions mediated by aromatic rings, a tyrosine grafted form of poly(L-lysine iso-phthalamide) was synthesized and its aqueous pH-sensitive properties, cytotoxicity and endosomal disruptive capacity were compared to phenylalanine-grafted poly(L-lysine iso-phthalamide). The similarity between these two polymers' properties, despite the large difference in hydrophobicity between their side-chains, supports the conclusion that the aromatic character of sidechains in poly(L-lysine iso-phthalamide) is an important property, as opposed to hydrophobicity alone, in determining the effectiveness of acidic pH triggered endosomolysis.

Neurological surgery at the National Institutes of Health.

The Surgical Neurology Branch (SNB) in the intramural program of the National Institute of Neurological Disorders and Stroke at the National Institutes of Health has been a unique setting for academic neurosurgery for nearly 60 years. Every patient evaluated and treated in the SNB is enrolled in a clinical research protocol, which underscores a singular focus on advancing neurosurgical research and patient care. Since the inception of the SNB, this research effort has been driven by dedicated clinician-investigators and basic scientists including Maitland Baldwin, Igor Klatzo, John M. Van Buren, Ayub K. Ommaya, Richard J. Youle, and Edward H. Oldfield. These and other SNB investigators have studied and advanced treatment of a number of neuropathologic processes, including delineation of differences between cytotoxic and vasogenic edema, head injury, Cushing disease, the effects of vascular endothelial growth factor in nervous system tissues, tumor suppressor syndromes, the pathophysiology of syringomyelia, mechanisms underlying cerebral vasospasm after subarachnoid hemorrhage, spinal arteriovenous malformations, mechanisms of cell death, and drug delivery. Currently, SNB efforts are focused on central nervous system drug delivery, the natural history of familial tumor syndromes, functional neurosurgery, epilepsy, vasospasm, and development of chemotherapeutics for malignant glioma. Throughout its history, the SNB has also been dedicated to training neurosurgeon clinician-investigators; 23 previous fellows/staff have become chairs of their respective neurosurgical departments. Recently, the commitment to training future neurosurgeon clinician-investigators has been further defined with the development of a residency-training program in neurological surgery approved in 2010.

Mechanistic and therapeutic implications of angiogenesis in endometriosis.

Like tumor metastases, endometriotic implants require neovascularization to proliferate and invade into ectopic sites within the host. Endometrial tissue, with its robust stem cell populations and remarkable regenerative capabilities, is a rich source of proangiogenic factors. Among the most potent and extensively studied of these proteins, vascular endothelial growth factor has emerged as a critical vasculogenic regulator in endometriosis. Accordingly, angiogenesis of the nascent endometriotic lesion has become an attractive target for novel medical therapeutics and strategies to inhibit vascular endothelial growth factor action. Vascular endothelial growth factor gene regulation in endometrial and endometriosis cells by nuclear receptors, other transcription factors, and also by infiltrating immune cells is emphasized. New data showing that oxidative and endoplasmic reticulum stress increase vascular endothelial growth factor expression are provided. Finally, we review the clinical implications of angiogenesis in this condition and propose potential antiangiogenic therapies that may become useful in the control or eradication of endometriotic lesions.

Follicular recruitment is reduced in minimal stimulation for controlled ovarian hyperstimulation using purified human menopausal gonadotropin compared with follicle-stimulating hormone.

Ovulation induction using a minimal stimulation protocol with clomiphene citrate and highly purified hMG was associated with a 20% reduction in the number of follicles recruited compared with clomiphene citrate and recombinant FSH. This reduction may reduce the risk of multiple gestation without reducing the pregnancy rate.

Nitrosoureas inhibit the stathmin-mediated migration and invasion of malignant glioma cells.

Malignant gliomas are the most common primary intrinsic brain tumors and are highly lethal. The widespread migration and invasion of neoplastic cells from the initial site of tumor formation into the surrounding brain render these lesions refractory to definitive surgical treatment. Stathmin, a microtubule-destabilizing protein that mediates cell cycle progression, can also regulate directed cell movement. Nitrosoureas, traditionally viewed as DNA alkylating agents, can also covalently modify proteins such as stathmin. We therefore sought to establish a role for stathmin in malignant glioma cell motility, migration, and invasion and determine the effects of nitrosoureas on these cell movement-related processes. Scratch wound-healing recovery, Boyden chamber migration, Matrigel invasion, and organotypic slice invasion assays were performed before and after the down-regulation of cellular stathmin levels and in the absence and presence of sublethal nitrosourea ([1-(2-chloroethyl)-3-cyclohexyl-l-nitrosourea]; CCNU) concentrations. We show that decreases in stathmin expression lead to significant decreases in malignant glioma cell motility, migration, and invasion. CCNU, at a concentration of 10 micromol/L, causes similar significant decreases, even in the absence of any effects on cell viability. The direct inhibition of stathmin by CCNU is likely a contributing factor. These findings suggest that the inhibition of stathmin expression and function may be useful in limiting the spread of malignant gliomas within the brain, and that nitrosoureas may have therapeutic benefits in addition to their antiproliferative effects.

Covalent modification of stathmin by CCNU determined by FTMS analysis of modified proteins and tryptic peptides.

Chemical modification of proteins is often carried out to generate protein-small molecule conjugates for various applications. The high resolution and mass accuracy of a Fourier transform mass spectrometer is particularly useful for assessing the extent or sites of covalent modifications. As protein-small molecule reactions often produce products with variable numbers of the compound incorporated at different sites, a direct mass analysis of the reaction products at times yields mass spectra hard to interpret. Chromatographic separation at protein level could reduce the complexity of a sample, thus allowing more accurate mass spectrometric analysis. In this report, we demonstrate the utility of reversed-phase protein chromatography and FT-ICR mass spectrometry in analyzing CCNU (lomustine, 1-(2-chloroethyl)-3-cyclohexyl-1-nitroso-urea, MW: 233.7Da) modification of stathmin. With this combined approach, we determined the stoichiometry as well as sites of CCNU incorporation into the protein, demonstrating differential reactivity of several lysyl residues to CCNU alkylation.