Perturbations in risk/reward decision making and frontal cortical catecholamine regulation induced by mild traumatic brain injury.

Mild traumatic brain injury (mTBI) disrupts cognitive processes that influence risk taking behavior. Little is known regarding the effects of repetitive mild injury (rmTBI) or whether these outcomes are sex specific. Risk/reward decision making is mediated by the prefrontal cortex (PFC), which is densely innervated by catecholaminergic fibers. Aberrant PFC catecholamine activity has been documented following TBI and may underlie TBI-induced risky behavior. The present study characterized the effects of rmTBI on risk/reward decision making behavior and catecholamine transmitter regulatory proteins within the PFC. Rats were exposed to sham, single (smTBI), or three closed-head controlled cortical impact (CH-CCI) injuries and assessed for injury-induced effects on risk/reward decision making using a probabilistic discounting task (PDT). In the first week post-final surgery, mTBI increased risky choice preference. By the fourth week, males exhibited increased latencies to make risky choices following rmTBI, demonstrating a delayed effect on processing speed. When levels of tyrosine hydroxylase (TH) and the norepinephrine reuptake transporter (NET) were measured within subregions of the PFC, females exhibited dramatic increases of TH levels within the orbitofrontal cortex (OFC) following smTBI. However, both males and females demonstrated reduced levels of OFC NET following rmTBI. These results indicate the OFC is susceptible to catecholamine instability after rmTBI and suggests that not all areas of the PFC contribute equally to TBI-induced imbalances. Overall, the CH-CCI model of rmTBI has revealed time-dependent and sex-specific changes in risk/reward decision making and catecholamine regulation following repetitive mild head injuries.

Increased Access, Persistent Disparities: Trends in Disparities in Peritoneal Dialysis (PD) Use, 2009-2019.

Peritoneal dialysis (PD) use has increased in the United States since 2009, but how this has affected disparities in PD use is unclear. We used data from the United States Renal Data System to identify a cohort of incident dialysis patients from 2009 to 2019. We used logistic regression models to examine how odds of PD use changed by demographic characteristics. The incident PD population increased by 203% from 2009 to 2019, and the odds of PD use increased in every subgroup. PD use increased more among older people because the odds for those aged 75 years or older increased 15% more per 5-year period compared with individuals aged 18-44 years (odds ratio [OR] 1.68, 95% confidence interval [CI], 1.64 to 1.73 versus OR 1.46, 95% CI, 1.42 to 1.50). The odds of PD use increased 5% more per 5-year period among Hispanic people compared with White people (OR 1.58, 95% CI, 1.53 to 1.63 versus OR 1.51, 95% CI, 1.48 to 1.53). There was no difference in odds of PD initiation among people who were Black, Asian, or of another race. The odds of PD use increased 5% more for people living in urban areas compared with people living in nonurban areas (5-year OR 1.54, 95% CI, 1.52 to 1.56 versus 5-year OR 1.46, 95% CI, 1.42 to 1.50). The odds of PD use increased 7% more for people living in socioeconomically advantaged areas compared with people living in more deprived areas (5-year OR 1.60, 95% CI, 1.56 to 1.63 for neighborhoods with lowest Social Deprivation Index versus 5-year OR 1.50, 95% CI, 1.48 to 1.53 in the most deprived areas). Expansion of PD use led to a reduction in disparities for older people and for Hispanic people. Although PD use increased across all strata of socioeconomic deprivation, the gap in PD use between people living in the least deprived areas and those living in the most deprived areas widened.

Association of the End-Stage Renal Disease Treatment Choices Payment Model With Home Dialysis Use at Kidney Failure Onset From 2016 to 2022.

Importance: The Centers for Medicare & Medicaid Services designed a mandatory payment model to incentivize home dialysis use: the End-Stage Renal Disease Treatment Choices (ETC). Outpatient dialysis facilities and health care professionals providing nephrology services were randomly assigned to ETC participation at the hospital referral region level. Objective: To assess the association between ETC and home dialysis use in the incident dialysis population in its first 18 months of implementation. Design, Setting, and Participants: A cohort study with controlled, interrupted time series analysis of the US End-Stage Renal Disease Quality Reporting System database was conducted, using generalized estimating equations. All adults initiating home-based dialysis in the US between January 1, 2016, and June 30, 2022, without a prior kidney transplant were included in the analysis. Exposures: Prior to vs after ETC onset in January 1, 2021, and random assignment to ETC participation of facilities and health care professionals involved in patient care. Main Outcomes and Measures: Percentage of patients started on incident home dialysis and yearly change in percentage initiating home dialysis. Results: A total of 817 177 adults initiated home dialysis during the study period, of whom 750 314 were included in the study cohort. The cohort included 41.4% women; 26.2% of the patients were Black, 17.4% were Hispanic, and 49.1% were White. Approximately half (49.6%) of the patients were aged at least 65 years. A total of 31.2% received care from health care professionals assigned to ETC participation, and 33.6% had Medicare fee-for-service coverage. Overall, home dialysis use increased from 10.0% in January 2016 to 17.4% in June 2022. Home dialysis use increased more in ETC markets than in non-ETC markets after January 2021 (by 1.07%; 95% CI, 0.16%-1.97%). The rate of increase in home dialysis use in the entire cohort nearly doubled after January 2021 to 1.66% per year (95% CI, 1.14%-2.19%) compared with before 2021, when the rate was 0.86% per year (95% CI, 0.75%-0.97%), but the difference in rate of increase in home dialysis use was not significant between ETC and non-ETC markets. Conclusions and Relevance: This study noted that, although the overall rate of dialysis use at home was greater after ETC implementation, the increase occurred more among patients in ETC markets than among those in non-ETC markets. These findings suggest that federal policy and financial incentives affected care for the entire incident dialysis population in the US.

Primary lacrimal gland plexiform neurofibroma: a case report and review of the literature.

Neurofibromatosis type 1 (NF1) affects cell growth in neural tissues, resulting in neurofibromas of the internal organs, peripheral nerves and/or autonomic nerves. We describe a highly unusual case of plexiform neurofibroma presenting with lacrimal gland enlargement in an 18 year old male, which led to a diagnosis of NF1.

The impact of low-dose aspirin in the Brain Injury Guidelines on outcomes in traumatic brain injury: A retrospective cohort study.

BACKGROUND: Current Brain Injury Guidelines (BIG) characterize patients with intracranial hemorrhage taking antiplatelet or anticoagulant agents as BIG 3 (the most severe category) regardless of trauma severity. This study assessed the risk of in-hospital mortality or need for neurosurgery in patients taking low-dose aspirin who otherwise would be classified as BIG 1. METHODS: This was a retrospective study at an academic level 1 trauma center. Patients were included if they were admitted with traumatic intracerebral hemorrhage and were evaluated by the BIG criteria. Exclusion criteria included indeterminate BIG status or patients with missing primary outcomes documentation. Patients were categorized as BIG 1, BIG 2, BIG 3, or BIG 1 on aspirin (patients with BIG 1 features taking low-dose aspirin). The primary endpoint was a composite of neurosurgical intervention and all-cause in-hospital mortality. Key secondary endpoints include rate of intracranial hemorrhage progression, and intensive care unit- and hospital-free days. RESULTS: A total of 1,520 patients met the inclusion criteria. Median initial Glasgow Coma Scale was 14 (interquartile range [IQR], 12-15), Injury Severity Scale score was 17 (IQR, 10-25), and Abbreviated Injury Scale subscore head and neck (AIS Head ) was 3 (IQR, 3-4). The rate of the primary outcome for BIG 1, BIG 1 on aspirin, BIG 2, and BIG 3 was 1%, 2.2%, 1%, and 27%, respectively; the difference between BIG 1 on aspirin and BIG 3 was significant ( p < 0.001). CONCLUSION: Patients taking low-dose aspirin with otherwise BIG 1-grade injuries experienced mortality and required neurosurgery significantly less often than other patients categorized as BIG 3. Inclusion of low-dose aspirin in the BIG criteria should be reevaluated. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.

A rare case of metastatic paraspinal rhabdomyosarcoma presenting with proptosis in an adult patient.

Secondary metastasis of rhabdomyosarcoma (RMS) to the orbit from a distant primary site is extremely rare in adults. In this article, we describe the case of a 24-year-old male presenting with proptosis, diplopia, and headaches concurrently with a histologically confirmed diagnosis of PAX3-FOXO1 positive paraspinal alveolar rhabdomyosarcoma. An orbital MRI revealed a fusiform mass arising from the inferior rectrus, displaying necrotic and irregular morphology consistent with malignancy. The patient is currently undergoing intensive chemotherapy. The objective of this case report is to highlight the rarity of an extraocular metastasis of RMS in an adult patient, alongside the importance of considering metastatic disease in a patient with fulminant unilateral proptosis.

Lacrimal gland extranodal marginal zone B-cell lymphoma in the presence of amyloidosis.

Amyloidosis is a protein metabolism disorder characterised by extracellular deposition of insoluble amorphous hyaline material. Orbital and ocular amyloid lesions account for only 4% of localised disease affecting the head and neck. Ocular adnexal lymphoma accounts for 1-2% of lymphoma, with lacrimal gland lymphomas being relatively uncommon. The most common form affecting the orbit is extranodal marginal zone lymphoma (EMZL) of mucosa-associated lymphoid tissue (MALT lymphoma). We report an extremely rare case of co-existent EMZL and amyloidosis of the lacrimal gland. Initial biopsy of the right lacrimal gland confirmed an EMZL with amyloid deposit, and a course of radiotherapy treatment was given. Recurrent lacrimal gland swelling developed within a year. Subsequent biopsy identified amyloidosis with scanty lymphoid tissue. To our knowledge, this is the first reported case of localised lacrimal gland amyloidosis of uncertain type with previous EMZL; the association described in this case report is not yet fully understood.

Metastatic testicular choriocarcinoma presenting as eyelid swelling and ptosis.

A 34-year-old man presented with an 8-day history of swelling and ptosis affecting the right upper eyelid. An MRI scan showed right superior rectus enlargement. Histology of an incisional biopsy of the muscle demonstrated metastatic choriocarcinoma to the orbit, positive for pan-cytokeratins, beta-HCG and GATA3. Possible primary sites included testis. An ultrasound of the testes identified bilateral testicular masses, highly suspicious for primary testicular malignancy. A CT scan of the chest, abdomen and pelvis identified disseminated metastatic disease conferring a poor prognostic germ cell tumour. The overall interpretation was of disseminated testicular choriocarcinoma and the patient is currently undergoing intensive chemotherapy.

Bilateral NAION and GPIbα gene.

BACKGROUND: It has been previously reported that one copy of the variable number tandem repeat (VNTR) B alleles of the GPIbα gene increases the risk of non-arteritic ischaemic optic neuropathy (NAION) and the second eye involvement. This is the first case where the presence of both alleles is associated with bilateral NAION. CASE PRESENTATION: A 52-year-old male presented with loss of vision in one eye and was diagnosed with NAION. The following year, he suffered another attack of NAION in the fellow eye. Genetic testing showed that he had both copies of VNTR B alleles of the GPIbα gene. CONCLUSIONS: We report a case of bilateral NAION in the presence of two copies of VNTR B alleles of the GPIbα gene. This may have further implications for the function of platelet glycoproteins.

Branched-Tail Lipid Nanoparticles Potently Deliver mRNA In Vivo due to Enhanced Ionization at Endosomal pH.

The potential of mRNA therapeutics will be realized only once safe and effective delivery systems are established. Unfortunately, delivery vehicle development is stymied by an inadequate understanding of how the molecular properties of a vehicle confer efficacy. Here, a small library of lipidoid materials is used to elucidate structure-function relationships and identify a previously unappreciated parameter-lipid nanoparticle surface ionization-that correlates with mRNA delivery efficacy. The two most potent materials of the library, 306O10 and 306Oi10 , induce substantial luciferase expression in mice following a single 0.75 mg kg-1 mRNA dose. These lipidoids, which have ten-carbon tails and identical molecular weights, vary only in that the 306O10 tail is straight and the 306Oi10 tail has a one-carbon branch. Remarkably, this small difference in structure conferred a tenfold improvement in 306Oi10 efficacy. The enhanced potency of this branched-tail lipidoid is attributed to its strong surface ionization at the late endosomal pH of 5.0. A secondary lipidoid library confirms that Oi10 materials ionize more strongly and deliver mRNA more potently than lipidoids containing linear tails. Together, these data highlight the exquisite control that lipid chemistry exerts on the mRNA delivery process and show that branched-tail lipids facilitate protein expression in animals.

Lipid nanoparticle siRNA cocktails for the treatment of mantle cell lymphoma.

Mantle cell lymphoma is an aggressive and incurable subtype of non-Hodgkin B cell lymphoma. Patients typically present with advanced disease, and most patients succumb within a decade of diagnosis. There is a clear and urgent need for novel therapeutic approaches that will affect mantle cell lymphoma through a unique mechanism compared to current therapies. This study examined the use of RNA interference (RNAi) therapy to attack mantle cell lymphoma at the mRNA level, silencing genes associated with cancer cell proliferation. We identified a lipid nanoparticle formulated with the lipidoid 306O13 that delivered siRNA to JeKo-1 and MAVER-1 mantle cell lymphoma cell lines. Three therapeutic gene targets were examined for their effect on lymphoma growth. These included Cyclin D1, which is a cell cycle regulator, as well as Bcl-2 and Mcl-1, which prevent apoptosis. Gene knockdown with siRNA doses as low at 10 nM increased lymphoma cell apoptosis without carrier-mediated toxicity. Silencing of Cyclin D1 induced apoptosis despite a twofold "compensation" upregulation of Cyclin D2. Upon simultaneous silencing of all three genes, nearly 75% of JeKo-1 cells were apoptosing 3 days post-transfection. Furthermore, cells proliferated at only 15% of their pretreatment rate. These data suggest that lipid nanoparticles-formulated, multiplexed siRNA "cocktails" may serve as a beneficial addition to the treatment regimens for mantle cell lymphoma and other aggressive cancers.

Lipidoid nanoparticle mediated silencing of Mcl-1 induces apoptosis in mantle cell lymphoma.

Conventional chemo-immunotherapy fails to cure the majority of mantle cell lymphoma patients and causes substantial toxicity. Resistant mantle cell lymphoma cells commonly overexpress and are dependent on the anti-apoptotic protein, Mcl-1, for survival. In this study, we use potent lipidoid nanoparticles to deliver siRNA to silence Mcl-1 expression. Studies were conducted using two different mantle cell lymphoma cell lines, a normal (JeKo-1) and an aggressive (MAVER-1) line, to assess the ability of lipidoid nanoparticles to be used broadly in the treatment of mantle cell lymphoma. Mcl-1 mRNA silencing and protein knockdown was observed as early as one day after treatment and the lipidoid nanoparticles achieved sustained silencing of Mcl-1 mRNA for at least four days in both JeKo-1 and MAVER-1 cells. Eighty percent silencing was achieved at three days post-transfection in JeKo-1 cells while 50% silencing was achieved in MAVER-1 cells, which are more resistant to transfection. Interestingly, silencing of Mcl-1 induced apoptosis in nearly 30% of both JeKo-1 and MAVER-1 cells three days post-transfection. Additionally, Mcl-1 silencing and the resultant apoptosis in mantle cell lymphoma cells were dose dependent. These data suggest that lipidoid nanoparticles siRNA therapy targeting Mcl-1 has potential as a new treatment modality for mantle cell lymphoma and many other cancers that overexpress Mcl-1. The combination of anti-Mcl-1 lipidoid nanoparticles with other forms of targeted therapy offers hope for reducing or replacing cytotoxic chemotherapy as standard treatment for mantle cell lymphoma.

Lipidoid Nanoparticles for siRNA Delivery to the Intestinal Epithelium: In Vitro Investigations in a Caco-2 Model.

Short interfering ribonucleic acid (siRNA) therapeutics show promise for the treatment of intestinal diseases by specifically suppressing the expression of disease relevant proteins. Recently, a class of lipid-like materials termed "lipidoids" have been shown to potently deliver siRNA to the liver and immune cells. Here, we seek to establish the utility of lipidoid nanoparticles (LNPs) in the context of siRNA delivery to the intestinal epithelium. Initial studies demonstrated that the siRNA-loaded LNPs mediated potent, dose dependent, and durable gene silencing in Caco-2 intestinal epithelial cells, with a single 10 nM dose depressing GAPDH mRNA expression for one week. Transfection with siRNA-loaded LNPs did not induce significant cytotoxicity in Caco-2 cells or alter intestinal barrier function. Protein silencing was confirmed by Western blotting, with the lowest levels of GAPDH protein expression observed five days post-transfection. Together, these data underscore the potential of LNPs for the treatment of intestinal disorders.

Introduction of a fresh cadaver laboratory during the surgery clerkship improves emergency technical skills.

BACKGROUND: Student acquisition of technical skills during the clinical years of medical school has been steadily declining. To address this issue, the authors instituted a fresh cadaver-based Emergency Surgical Skills Laboratory (ESSL). METHODS: Sixty-three medical students rotating through the third-year surgery clerkship participated in a 2-hour, fresh cadaver-based ESSL conducted during the first 2 days of the clerkship. The authors evaluated students utilizing both surgical skills and written examination before the ESSL and at 4 weeks post ESSL. RESULTS: Students demonstrated a mean improvement of 64% (±11) (P < .001) and 38% (±17) (P < .001) in technical skills and clinical knowledge, respectively. When technical skills were compared between cohorts, there were no differences observed in both pre- and post-testing (P = .08). CONCLUSIONS: A fresh cadaver laboratory is an effective method to provide proficiency in emergency technical skills not acquired during the clinical years of medical school.

In pursuit of a moving target: nanotherapeutics for the treatment of non-Hodgkin B-cell lymphoma.

INTRODUCTION: Non-Hodgkin lymphoma (NHL) is diagnosed in 70,000 Americans annually. Chemotherapy was the standard course of treatment until the addition of the monoclonal antibody (mAb) drug, rituximab, to therapy regimens in 1997. Although disease prognosis has improved dramatically since that time, nearly 20,000 patients succumb annually to the disease, with an average life expectancy beyond diagnosis of only 12 years. The advent of nanomedicine may fulfill the remaining need for novel therapy capable of eradicating solid tumor and disseminated B-cell lymphomas. AREAS COVERED: This review details the current landscape of B-cell NHL and nanoparticles now being developed for its treatment. Specifically, we discuss lipid, polymer and metal nanoparticles that deliver an array of drugs, including toxins, chemotherapeutic agents and nucleic acids. EXPERT OPINION: Because B-cell malignancies have responded quite well to new components in multi-drug regimens, nanomedicines that are mechanistically distinct from existing therapies hold significant promise. In our opinion, advancement of these technologies into the clinic will likely require significantly more effective targeting systems coupled with a better understanding of lymphoma biology. Furthermore, it is important for researchers to recognize the genetic and phenotypic heterogeneity of NHL and to develop therapeutic strategies for distinct subsets of NHL before attempting to generalize approaches.