Citations

Heřmanský–Pudlák syndrome (HPS), a rare autosomal recessive disorder, manifests with oculocutaneous albinism and a bleeding diathesis. However, severity of disease can be variable and is typically related to the genetic subtype of HPS; HPS type 6 (HPS‐6) is an uncommon subtype generally associated with mild disease. A Caucasian adult female presented with a history of severe bleeding; ophthalmologic examination indicated occult oculocutaneous albinism. The patient was diagnosed with a platelet storage pool disorder, and platelet whole mount electron microscopy demonstrated absent delta granules. Genome‐wide SNP analysis showed regions of homozygosity that included the HPS1 and HPS6 genes. Full length HPS1 transcript was amplified by PCR of genomic DNA. Targeted next‐generation sequencing identified a novel homozygous missense variant in HPS6 (c.383 T > C; p.V128A); this was associated with significantly reduced HPS6 mRNA and protein expression in the patient's fibroblasts compared to control cells. These findings highlight the variable severity of disease manifestations in patients with HPS, and illustrate that HPS can be diagnosed in patients with excessive bleeding and occult oculocutaneous albinism. Genetic analysis and platelet electron microscopy are useful diagnostic tests in evaluating patients with suspected HPS.Clinical Trial registration:Registrar: ClinicalTrials.govWebsite: www.clinicaltrials.govRegistration Numbers: NCT00001456 and NCT00084305.

Abstract Although fast-scan cyclic voltammetry (FSCV) has been widely used for in vivo neurochemical detection, the sensitivity and selectivity of the technique can be further improved. In this study, we develop fast cyclic square-wave voltammetry (FCSWV) as a novel voltammetric technique that combines large-amplitude cyclic square-wave voltammetry (CSWV) with background subtraction. A large-amplitude, square-shaped potential was applied to induce cycling through multiple redox reactions within a square pulse to increase sensitivity and selectivity when combined with a two-dimensional voltammogram. As a result, FCSWV was significantly more sensitive than FSCV (n = 5 electrodes, two-way ANOVA, p = 0.0002). In addition, FCSWV could differentiate dopamine from other catecholamines (e.g., epinephrine and norepinephrine) and serotonin better than conventional FSCV. With the confirmation that FCSWV did not influence local neuronal activity, despite the large amplitude of the square waveform, it could monitor electrically induced phasic changes in dopamine release in rat striatum before and after injecting nomifensine, a dopamine reuptake inhibitor.

BACKGROUND: African-Americans (AA) have a higher incidence of hepatocellular carcinoma (HCC) and lower survival. We characterized survival rates and clinical features associated with survival in AA vs. Caucasians with HCC over the past two decades. METHODS: HCC patients from three US medical centers were matched by year of diagnosis (1991–2016): AA ( n = 578)/Caucasian ( n = 578) and placed in one of two groups—HCC diagnosed prior to 2010 or 2010 and after. Data were obtained from chart review and the National Death Index. Multivariate and survival analysis controlling for key predictors were conducted. RESULTS: Prior to 2010, there was no difference in survival between Caucasians and AA ( p = 0.61). After 2010, AA patients had poorer survival compared to Caucasians (35% vs. 44%, respectively, p = 0.044). Over time, survival improved for Caucasians (32% before 2010 vs. 44% after 2010, p = 0.003), but not AA (36% vs. 35%, p = 0.50). AA on presentation (in the after 2010 cohort) were more likely to have BCLC (Barcelona Clinic Liver Cancer) stage C (24% vs. 15%, p = 0.010) and less likely to receive treatment (85% vs. 93%, p = 0.002) compared to matched Caucasians. BCLC beyond stage A (aHR: 1.75, 95% CI: 1.26–2.43, p = 0.001) and child’s class C (aHR 2.05, 95% CI: 1.23–3.41, p = 0.006) were the strongest predictors of mortality, while race was not. CONCLUSIONS: African-Americans presented with more advanced HCC and had poorer survival compared to Caucasians after 2010. Tumor stage was an independent predictor of mortality, but ethnicity was not. Further efforts are needed to improve early HCC diagnosis for AA.

Duchenne muscular dystrophy (DMD) is a musculoskeletal disorder that causes severe morbidity and reduced lifespan. Individuals with DMD have an X-linked mutation that impairs their ability to produce functional dystrophin protein in muscle. No cure exists for this disease and the few therapies that are available do not dramatically delay disease progression. Thus, there is a need to better understand the mechanisms underlying DMD which may ultimately lead to improved treatment options. The muscular dystrophy (MDX) mouse model is frequently used to explore DMD disease traits. Though some studies of metabolism in dystrophic mice exist, few have characterized metabolic profiles of supporting cells in the diseased environment. Using nontargeted metabolomics we characterized metabolic alterations in muscle satellite cells (SCs) and serum of MDX mice. Additionally, live-cell imaging revealed MDX-derived adipose progenitor cell (APC) defects. Finally, metabolomic studies revealed a striking elevation of acylcarnitines in MDX APCs, which we show can inhibit APC proliferation. Together, these studies highlight widespread metabolic alterations in multiple progenitor cell types and serum from MDX mice and implicate dystrophy-associated metabolite imbalances in APCs as a potential contributor to adipose tissue disequilibrium in DMD.

Purpose: Photic retinal toxicity induced by exposure to arc welding can lead to irreversible vision loss. Serial multimodal imaging is characterized in a patient with outer retinal damage secondary to welder's maculopathy. Methods: A single case was retrospectively reviewed. Results: Spectral domain optical coherence tomography acutely revealed disruption of the ellipsoid zone, hyperreflective bands through the outer nuclear layer, and outer retinal cavitation consistent with phototoxicity. Subsequently, disruption and hypertrophy of the subfoveal retinal pigment epithelium developed. Autofluorescence depicted central hypoautofluorescence. Conclusion: We report serial multimodal imaging in welder's maculopathy to better characterize the evolution of lesions. Multimodal imaging including spectral domain optical coherence tomography in arc welding phototoxicity may share features with other forms of phototoxicity such as hand-held laser maculopathy.

Neuropathic pain (NP) is caused by lesions of the peripheral fibers and central neurons in the somatosensory nervous system and affects 7–10% of the general population. Although the distinct cause of neuropathic pain has been investigated in primary afferent neurons over the years, pain modulation by central sensitization remains controversial. NP is believed to be driven by cell type-specific spinal synaptic plasticity in the dorsal horn. Upon intense afferent stimulation, spinothalamic tract neurons are potentiated, whereas GABAergic interneurons are inhibited leading to long-term depression. Growing evidences suggest that the inhibition of GABAergic neurons plays pivotal roles in the manifestation of neuropathic and inflammatory pain states. Downregulation of GABA transmission and impairment of GABAergic interneurons in the dorsal horn are critical consequences after spinal cord and peripheral nerve injuries. These impairments in GABAergic interneurons may be associated with dysfunctional autophagy, resulting in neuropathic pain. Here, we review an emerging number of investigations that suggest a pivotal role of impaired autophagy of GABAergic interneurons in NP. We discuss relevant research spurring the development of new targets and therapeutic agents of NP and emphasize the need for a multidisciplinary approach to manage NP in the future.