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INTRODUCTION: While selective dorsal rhizotomy (SDR) was originally described as a multilevel approach, single-level approaches are now popularized. Conus localization is beneficial for operative planning in single-level selective dorsal rhizotomy. Our approach to SDR involves minimal exposure for a single-level laminoplasty, preserving one attached interspinous ligament. Pre-operative conus localization is required for this tailored approach to determine the laminoplasty level and dictate rostral or caudal division of the superior spinus ligament. While rapid MRI sequences have been popularized for pediatric cranial imaging, its utility for spinal imagining is less well-described, and specific application for conus localization has not been reported. OBJECTIVE: Illustrate that rapid MRI without sedation is sufficient to identify conus level for tailored single-level laminoplasty SDR. MATERIAL AND METHODS: Patients undergoing SDR from 2014 to 2022 at one institution were reviewed for type of pre-operative MRI (rapid vs full), conus level, procedural time for MRI, and radiology report. The typical rapid MRI has four sequences utilizing single-shot technique (scout, sagittal T2, axial T2, and axial T1) that typically take less than 1 min each of acquisition time, with non-single-shot sequences added periodically in cooperative patients. To include time for patient positioning, pre-scan shimming, procedural incidentals, and other patient-specific variations, MRI procedure length was recorded as documented in the electronic medical record. RESULTS: N = 100 patients had documentation of an MRI for pre-operative imaging. Seventy-nine of these had a rapid MRI, and 21 required a full MRI with anesthesia for their treatment plan. Mean total procedure time for rapid MRI was 21.5 min (median 17). Mean procedure time for MRI under general anesthesia was 91.2 min (median 94). Of patients with rapid MRI imaging, 2/79 had an ambiguous conus level (1 from motion artifact, 1 from spinal hardware) vs 1/21 with a full MRI under anesthesia (due to spinal hardware). CONCLUSION: Rapid spinal MRI without sedation can be used for conus localization in a pediatric population. This may be routinely used as pre-operative imaging for a single-level approach to selective dorsal rhizotomy, without sedation or intubation procedures.

HIV-1 genotypic resistance test were obtained on clinical samples from 116 patients with plasma, HIV RNA levels of less than 75 copies/mL. Genotypic validity was confirmed in 49 of 50 patients with a previous or follow-up genotype.

Summary. Angiogenesis is one of critical factors in sustaining the growth, invasion and metastasis of certain solid tumours and haematological malignancies such as multiple myeloma (MM). In the present study, we examined the anticancer potential of an inhibitor of nitric oxide synthase (NOS), NG -nitro-l-arginine methyl ester (L-NAME), in a novel severe combined immunodeficient mouse model (KHM mouse) that harbours the highly sanguineous plasmacytoma cell line KHM-4, derived from a patient with highly chemoresistant MM. KHM mice were intraperitoneally administered with either L-NAME, doxorubicin, melphalan, or paclitaxel. A significant reduction in tumour sizes was noted in L-NAME-administered KHM mice while no significant reduction was observed in melphalan- or doxorubicin-administered mice. A profound decrease in angiogenesis was observed in tumour tissues from L-NAME- and paclitaxel-administered KHM mice. A marked decrease in human vascular endothelial cell growth factor (VEGF) levels was identified in tumour tissues from L-NAME-administered KHM mice, strongly suggesting that L-NAME suppressed VEGF production by tumour cells through its inhibition of NOS in tumour cells, resulting in reduced neovasculization in mice leading to the regression of tumour sizes. The present data represent the first observations that certain NOS inhibitors potentially serve as experimental agents for the treatment of chemoresistant MM and plasmacytoma. [ABSTRACT FROM AUTHOR]

The detection of mutant spectra within a population of microorganisms is critical for the management of drug-resistant infections. We performed ultra-deep pyrosequencing to detect minor sequence variants in HIV-1 protease and reverse transcriptase (RT) genes from clinical plasma samples. We estimated empirical error rates from four HIV-1 plasmid clones and used them to develop a statistical approach to distinguish authentic minor variants from sequencing errors in eight clinical samples. Ultra-deep pyrosequencing detected an average of 58 variants per sample compared with an average of eight variants per sample detected by conventional direct-PCR dideoxynucleotide sequencing. In the clinical sample with the largest number of minor sequence variants, all 60 variants present in =3% of genomes and 20 of 35 variants present in <3% of genomes were confirmed by limiting dilution sequencing. With appropriate analysis, ultra-deep pyrosequencing is a promising method for characterizing genetic diversity and detecting minor yet clinically relevant variants in biological samples with complex genetic populations. [ABSTRACT FROM AUTHOR]