Treatment with the vascular endothelial growth factor-A antibody, bevacizumab, has sex-specific effects in a rat model of mild traumatic brain injury

Mild traumatic brain injury (mTBI) involves damage to the cerebrovascular system. Vascular endothelial growth factor-A (VEGF-A) is an important modulator of vascular health and VEGF-A promotes the brain's ability to recover after more severe forms of brain injury; however, the role of VEGF-A in mTBI remains poorly understood. Bevacizumab (BEV) is a monoclonal antibody that binds to VEGF-A and neutralises its actions. To better understand the role of VEGF-A in mTBI recovery, this study examined how BEV treatment affected outcomes in rats given a mTBI. Adult Sprague-Dawley rats were assigned to sham-injury + vehicle treatment (VEH), sham-injury + BEV treatment, mTBI + VEH treatment, mTBI + BEV treatment groups. Treatment was administered intracerebroventricularly via a cannula beginning at the time of injury and continuing until the end of the study. Rats underwent behavioral testing after injury and were euthanized on day 11. In both females and males, BEV had a negative impact on cognitive function. mTBI and BEV treatment increased the expression of inflammatory markers in females. In males, BEV treatment altered markers related to hypoxia and vascular health. These novel findings of sex-specific responses to BEV and mTBI provide important insights into the role of VEGF-A in mTBI.

A pre-existing Toxoplasma gondii infection exacerbates the pathophysiological response and extent of brain damage after traumatic brain injury in mice

Traumatic brain injury (TBI) is a key contributor to global morbidity that lacks effective treatments. Microbial infections are common in TBI patients, and their presence could modify the physiological response to TBI. It is estimated that one-third of the human population is incurably infected with the feline-borne parasite, Toxoplasma gondii, which can invade the central nervous system and result in chronic low-grade neuroinflammation, oxidative stress, and excitotoxicity-all of which are also important pathophysiological processes in TBI. Considering the large number of TBI patients that have a pre-existing T. gondii infection prior to injury, and the potential mechanistic synergies between the conditions, this study investigated how a pre-existing T. gondii infection modified TBI outcomes across acute, sub-acute and chronic recovery in male and female mice. Gene expression analysis of brain tissue found that neuroinflammation and immune cell markers were amplified in the combined T. gondii + TBI setting in both males and females as early as 2-h post-injury. Glutamatergic, neurotoxic, and oxidative stress markers were altered in a sex-specific manner in T. gondii + TBI mice. Structural MRI found that male, but not female, T. gondii + TBI mice had a significantly larger lesion size compared to their uninfected counterparts at 18-weeks post-injury. Similarly, diffusion MRI revealed that T. gondii + TBI mice had exacerbated white matter tract abnormalities, particularly in male mice. These novel findings indicate that a pre-existing T. gondii infection affects the pathophysiological aftermath of TBI in a sex-dependent manner, and may be an important modifier to consider in the care and prognostication of TBI patients.

Unit costs of needle and syringe program provision: a global systematic review and cost extrapolation

BACKGROUND

Needle and syringe programs (NSPs) are effective at preventing HIV and hepatitis C virus (HCV) among people who inject drugs (PWID), yet global coverage is low, partly because governments lack data on the cost and cost-effectiveness of NSP in their countries to plan and fund their responses. We conducted a global systematic review of unit costs of NSP provision to inform estimation of cost drivers and extrapolated costs to other countries.

METHODS

We conducted a systematic review to extract data on the cost per syringe distributed and its cost drivers. We estimated the impact of country-level and program-level variables on the cost per syringe distributed using linear mixed-effects models. These models were used to predict unit costs of NSP provision, with the best performing model used to extrapolate the cost per syringe distributed for 137 countries. The total cost for a comprehensive NSP (200 syringes per PWID/year) was also estimated for 68 countries with PWID population size estimates.

RESULTS

We identified 55 estimates of the unit cost per syringe distributed from 14 countries. Unit costs were extrapolated for 137 countries, ranging from $0.08 to $20.77 (2020 USD) per syringe distributed. The total estimated spend for a high-coverage, comprehensive NSP across 68 countries with PWID size estimates is $5 035 902 000 for 10 887 500 PWID, 2.1-times higher than current spend.

CONCLUSION

Our review identified cost estimates from high-income, upper-middle-income, and lower-middle-income countries. Regression models may be useful for estimating NSP costs in countries without data to inform HIV/HCV prevention programming and policy.

Topical Pharmacokinetics of Brinzolamide Suspensions in Rabbits and Variability Analysis for Sample Size and Design Considerations

Identifying critical attributes for complex locally acting ophthalmic formulations and establishing in vitro-in vivo correlations can facilitate selection of appropriate thresholds for formulation changes that reflect lack of impact on in vivo performance. In this study the marketed antiglaucoma product Azopt® (1% brinzolamide suspension) and five other brinzolamide formulations varying in particle size distributions and apparent viscosities were topically administered in rabbits, and their ocular pharmacokinetics was determined in multiple ocular tissues. Statistical evaluation with ANOVA showed no significant differences between the formulations in the peak drug concentration (C_max) in the aqueous humor and iris-ciliary body. As a post-hoc analysis, the within animal and total variability was determined for C_max in the aqueous humor and iris-ciliary body. Based on the observed variability, we investigated the sample size needed for two types of study designs to observe statistically significant differences in C_max. For the sample size calculations, assuming both 25% and 50% true differences in C_max between two formulations, two study designs were compared: paired-eye dosing design (one formulation in one eye and another formulation in the other eye of the same animal at the same time) versus parallel-group design. The number of rabbits needed in the paired-eye dosing design are much lower than in the parallel-group design. For example, when the true difference in aqueous humor C_max is 25%, nine rabbits are required in the paired-eye design versus seventy rabbits (35 per treatment) in the parallel-group design to observe a statistically significant difference with a power of 80%. Therefore, the proposed paired-eye dosing design is a viable option for the design of pharmacokinetic studies comparing ophthalmic products to determine the impact of formulation differences.

Pre-existing Toxoplasma gondii infection increases susceptibility to pentylenetetrazol-induced seizures independent of traumatic brain injury in mice

Introduction

Post-traumatic epilepsy (PTE) is a debilitating chronic outcome of traumatic brain injury (TBI), and neuroinflammation is implicated in increased seizure susceptibility and epileptogenesis. However, how common clinical factors, such as infection, may modify neuroinflammation and PTE development has been understudied. The neurotropic parasite, Toxoplasma gondii (T. gondii) incurably infects one-third of the world's population. Thus, many TBI patients have a pre-existing T. gondii infection at the time of injury. T. gondii infection results in chronic low-grade inflammation and altered signaling pathways within the brain, and preliminary clinical evidence suggest that it may be a risk factor for epilepsy. Despite this, no studies have considered how a pre-existing T. gondii infection may alter the development of PTE.

Methods

This study aimed to provide insight into this knowledge gap by assessing how a pre-existing T. gondii infection alters susceptibility to, and severity of, pentylenetetrazol (PTZ)-induced seizures (i.e., a surrogate marker of epileptogenesis/PTE) at a chronic stage of TBI recovery. We hypothesized that T. gondii will increase the likelihood and severity of seizures following PTZ administration, and that this would occur in the presence of intensified neuroinflammation. To test this, 6-week old male and female C57BL/6 Jax mice were intraperitoneally injected with 50,000 T. gondii tachyzoites or with the PBS vehicle only. At 12-weeks old, mice either received a severe TBI via controlled cortical impact or sham injury. At 18-weeks post-injury, mice were administered 40 mg/kg PTZ and video-recorded for evaluation of seizure susceptibility. Fresh cortical tissue was then collected for gene expression analyses.

Results

Although no synergistic effects were evident between infection and TBI, chronic T. gondii infection alone had robust effects on the PTZ-seizure response and gene expression of markers related to inflammatory, oxidative stress, and glutamatergic pathways. In addition to this, females were more susceptible to PTZ-induced seizures than males. While TBI did not impact PTZ responses, injury effects were evident at the molecular level.

Discussion

Our data suggests that a pre-existing T. gondii infection is an important modifier of seizure susceptibility independent of brain injury, and considerable attention should be directed toward delineating the mechanisms underlying this pro-epileptogenic factor.

Prioritization of carceral spending in U.S. cities: Development of the Carceral Resource Index (CRI) and the role of race and income inequality

BACKGROUND

Policing, corrections, and other carceral institutions are under scrutiny for driving health harms, while receiving disproportionate resources at the expense of prevention and other services. Amidst renewed interest in structural determinants of health, roles of race and class in shaping government investment priorities are poorly understood.

METHODS

Based on the Social Conflict Model, we assessed relationships between city racial/ economic profiles measured by the Index of Concentration at the Extremes (ICE) and budgetary priorities measured by the novel Carceral Resource Index (CRI), contrasting investments in carceral systems with funding for health and social support across the 50 most populous cities in the United States (U.S.). Bivariate correlations, and unadjusted and adjusted polynomial regression models were used to assess the relationship between budgetary investments and population concentration at extremes in terms of income, racial/ethnic composition, and education, controlling for other demographic characteristics.

RESULTS

In our sample, median CRI was -0.59 (IQR -0.64, -0.45), with only seven cities exhibiting positive CRI values. This indicates that most large U.S. cities spend more on carceral systems than on health and supportive services, combined. Adjusted polynomial models showed a convex relationship between the CRI and ICE-Education, and ICE-Race(White vs. Black)+Income, with quadratic terms that were positive and significant at p<0.05. After controlling for age, the strongest prioritization of carceral systems was observed in cities where the proportion of low-income Black residents approached or exceeded that of high-income white residents.

CONCLUSIONS

Municipal prioritization of carceral investments over health and social support is pervasive in the U.S and exacerbated by racial and economic disparities. The CRI offers new opportunities to understand the role of government investments as a structural determinant of health and safety. Longitudinal research is warranted to examine the relationship between budget priorities, structural racism, and health outcomes.

Treatment with vascular endothelial growth factor-A worsens cognitive recovery in a rat model of mild traumatic brain injury

Mild traumatic brain injury (mTBI) is a common and unmet clinical issue, with limited treatments available to improve recovery. The cerebrovascular system is vital to provide oxygen and nutrition to the brain, and a growing body of research indicates that cerebrovascular injury contributes to mTBI symptomatology. Vascular endothelial growth factor-A (VEGF-A) is a potent promoter of angiogenesis and an important modulator of vascular health. While indirect evidence suggests that increased bioavailability of VEGF-A may be beneficial after mTBI, the direct therapeutic effects of VEGF-A in this context remains unknown. This study therefore aimed to determine whether intracerebroventricular administration of recombinant VEGF-A could improve recovery from mTBI in a rat model. Male and female Sprague-Dawley rats were assigned to four groups: sham + vehicle (VEH), sham + VEGF-A, mTBI + VEH, mTBI + VEGF-A. The mTBI was induced using the lateral impact model, and treatment began at the time of the injury and continued until the end of the study. Rats underwent behavioral testing between days 1 and 10 post-injury, and were euthanized on day 11 for post-mortem analysis. In males, the mTBI + VEGF-A group had significantly worse cognitive recovery in the water maze than all other groups. In females, the VEGF treatment worsened cognitive performance in the water maze regardless of mTBI or sham injury. Analysis of hippocampal tissue found that these cognitive deficits occurred in the presence of gene expression changes related to neuroinflammation and hypoxia in both male and female rats. These findings indicate that the VEGF-A treatment paradigm tested in this study failed to improve mTBI outcomes in either male or female rats.

Abstract WP253: Increased Hydrogen Sulfide As A New Mechanism For Hyperglycemic Worsening Of Stroke Outcome

Introduction: Hyperglycemia at stroke onset worsens outcome and reduces the effectiveness of reperfusion therapies. Increased oxidative and mitochondrial injury likely contribute. To treat this mechanism, we synthesized (PEG)-ylated carbon nanoparticles (CNPs) from acid oxidation of activated charcoal (OAC) generating 3 nm discs, catalytic superoxide dismutase mimetics that protect mitochondrial complexes. Cellular uptake is rapid and delayed I.V. PEG-CNPs are highly protective in reversible MCAO in hyperglycemic rats. Hydrogen sulfide (H 2 S) is an essential gaseous transmitter with a narrow therapeutic index associated with many disorders e.g., diabetes. Its synthesis is influenced by radicals. Excess H 2 S is toxic to mitochondrial complex IV. H 2 S is endogenously oxidized to polysulfides (PS), potent antioxidants also needed for protein persulfidation. We hypothesized that OAC’s favorable redox potential will catalyze H 2 S oxidization to PS, acute hyperglycemia will increase H 2 S and PEG-OACs will blunt the increase.

Methods: b.End3 brain endothelial and HEK293 cultured cells were employed. SSP4 fluorescence measured PS levels with increasing concentrations of PEG-OACs. AzMC fluorescence detected H 2 S levels in cells incubated in 100 mg/dL glucose media followed by glucose 500 mg/dL with or without PEG-OACs, first in normoxia followed by anoxia/normoxia.

Results: PEG-OACs dose dependently increased cellular PS levels (Fig 1a). High glucose increased H 2 S levels especially during anoxia/normoxia (Fig 1b). PEG-OACs completely eliminated the glucose-induced increase in H 2 S (Fig 1c).

Conclusions: Acute hyperglycemia increased H 2 S production especially under conditions mimicking ischemia/reperfusion, an effect eliminated by PEG-OACs. Because of mitochondrial toxicity, an H 2 S increase may contribute to worsened outcome in hyperglycemic stroke. These results suggest a new therapeutic target for this important cause of poor stroke outcome.

Quantification of Scan Analysis Errors in GE Lunar DXA Visceral Adiposity in Adults

Utilization of dual-energy X-ray absorptiometry is increasing in clinical settings and the fitness industry as a viable tool to assess total and regional body composition, including visceral adiposity. Previous research using small samples (<50) has described several pitfalls in patient positioning, scan acquisition, and/or analysis that alter regional body composition values. Our aim was to quantify the largest probable error in measures of total, android, gynoid, and visceral fat caused by incorrect placement of the head cut-line, in a large sample of adults. Total body images (N = 436) from 196 women and 67 men (20-85 years) scanned on a GE Lunar Prodigy densitometer were analyzed using enCORE software in 2 ways: (1) placing the head cut-line just beneath the bony protuberance of the chin according to manufacturer recommendation (correct method); (2) placing the head cut-line at the lowest point below the chin and just above the soft tissue at the shoulders (incorrect method). All other cut-lines were fixed. Mean differences in adiposity were examined using Lin's concordance correlation coefficient; equality of means and variances were evaluated using Bradley-Blackwood F-tests. The limits of agreement were displayed as Bland-Altman plots and calculated as the mean difference ±1.96 times the standard deviation of the difference. Correlation coefficients for paired comparisons of adiposity for correct vs incorrect cut-line placement ranged from 0.983-0.999 for all variables (all p < 0.001). Significant mean differences were 172 ± 130, 201 ± 168, 65 ± 122, and -143 ± 336 g for android, gynoid, visceral, and total fat mass, respectively (all p < 0.0001). These differences exceeded our site's least significant change in 66%, 37%, 29%, and 4% of participant scans for android, gynoid, visceral, and total fat mass, respectively. Our findings underscore the importance of careful review of the manufacturer's auto analysis and consistency in conducting serial scans to ensure accurate and precise measures of regional body fat.

Analyzing ophthalmic suspension particle size distributions using laser diffraction: Placebo background subtraction method

The current study demonstrated that the presence of excipients can interfere with the measurement of particle size distribution (PSD), a critical quality attribute of ophthalmic suspensions, by laser diffraction (LD) and that a placebo background subtraction approach can eliminate the impact of excipients on the PSD measurement. Commercially available loteprednol etabonate and brinzolamide ophthalmic suspensions were used as model suspensions. The impact of excipients in these formulations on the LD measurements was determined using a one-factor-at-a-time experimental design approach, using National Institute of Standards and Technology (NIST) traceable polystyrene particle size standards as references. Among the evaluated excipients, polymers containing polyacrylic acid were found to interfere with the PSD analysis by creating the LD signals correspond to particles ranging from a few micrometers to a hundred micrometers in size. As a result, the measured PSD of active pharmaceutical ingredient (API) particles in the formulation overlapped with or superimposed on the excipient PSD signal, leading to erroneous interpretation of the API particle size. Additionally, dispersion of brinzolamide particles in unsaturated solutions led to rapid dissolution of brinzolamide particles during the measurement, resulting in underestimation of the particle size range. Here, a placebo background subtraction approach was developed to eliminate the interference of the excipients. This newly developed LD method was also evaluated using orthogonal methods, including polarized light microscopy and scanning electron microscopy (SEM). The strategy used in this study to eliminate the interference of excipients may also be useful for other heterogeneous dispersions where excipient interference may be of concern.

In vitro physicochemical characterization and dissolution of brinzolamide ophthalmic suspensions with similar composition

The quality of an ophthalmic suspension is crucial for its in vivo performance, and often impact product's effectiveness. An in-depth understanding of critical quality attributes (CQAs) of ophthalmic suspensions such as particle size distribution (PSD) and rheology, as well as the impact of these CQAs on product performance are important for successful product development, quality control, and regulatory approval. This study employed brinzolamide ophthalmic suspension, 1%, as a model ophthalmic product, and six batches were manufactured using an innovative planetary centrifugal milling (PCM) process. Three batches were manufactured to have distinctly different PSD. These three batches had qualitatively (Q1) and quantitatively (Q2) the same composition as the model drug product (i.e., Azopt), while the differences in PSD were introduced by changing only the manufacturing process parameters. On the other hand, changes in rheology were introduced by altering the input level of the viscosity enhancing polymer in the formulation. A systematic approach was employed to understand the relation between manufacturing process parameters, CQAs, and in vitro product performance. Among the evaluated CQAs, PSD, rheology, surface tension, and drug dissolution were found more sensitive to the changes in the manufacturing processes. Most notably, we developed a rapid dissolution method (completed within minutes) employing in-situ fiber optic UV dissolution system. This novel dissolution method mimics the environmental conditions of the eye such as dissolution under "non-sink" condition and under high shear (from blinking). The method was highly discriminatory to differences in the PSD in the suspension. This study also revealed an important relation between the PSD of the suspension and its rheology which originated as a result of an interaction at the molecular level between the solid drug particles and the viscosity enhancing polymers. These findings underscore the need to evaluate CQAs of the ophthalmic suspensions in concert rather than separately when comparing ophthalmic drug products and product performance.

Progressive Left Ventricular Hypertrophy After Ozaki Procedure: A Case Report

We describe a 57-year-old man with symptomatic severe aortic stenosis who underwent aortic valve reconstruction with glutaraldehyde-treated autologous pericardium with the Ozaki technique (Ozaki procedure). Seven months later, he rapidly developed progressive left ventricular hypertrophy with a left ventricular outflow tract obstruction. This required a reoperation for septal myectomy.

Minimally invasive surgical repair of accessory mitral valve tissue: A case report

INTRODUCTION

Accessory mitral valve tissue is a rare congenital disease of the mitral valve. It is usually associated with other cardiac malformations and/or left ventricular outflow tract obstruction. More than 2/3 of patients were diagnosed in their childhood. Treatment can be conservative or surgical. The suitable timing for surgery remains controversial, some authors suggest early intervention to prevent devastating complications.

CASE REPORT

We report a case of an adult patient with accessory mitral valve tissue causing left ventricular outflow tract obstruction, who was treated surgically via the right minithoracotomy.

Factors affecting the particle size distribution and rheology of brinzolamide ophthalmic suspensions

Drug particle size distribution (PSD) and dispersion viscosity are two critical quality attributes that govern the performance of topical ophthalmic suspensions, such as suspension physical stability, ocular retention, and drug release characteristics.. An in-depth knowledge of the effects of formulation and manufacturing process on these critical quality attributes may facilitate the product and process development, quality control, as well as support regulatory policy and approval. The current study has investigated the effect of formulation and process parameters on the quality attributes of brinzolamide ophthalmic suspensions. In the first step, three milling techniques (probe sonication, microfluidization, and media milling with a planetary centrifugal mixer) were evaluated for manufacturing of brinzolamide suspension. Out of the three techniques, the planetary centrifugal media milling yielded the narrowest PSD and thus was considered the most viable lab-scale technique for this purpose. In the next step, various process parameters of media milling were evaluated using a central-composite experimental design. The independent variables included bead size, agitating intensity, and process time while the PSD of drug particles (D₅₀) was the response variable. The effect of shear rate and shear time of the homogenization process and the concentration of carbomer on the rheological properties of the suspension were studied using a Box-Behnken design. Additionally, effects of sodium chloride and mannitol concentration on the rheological properties of the suspension was also investigated. Sodium chloride was found to exert a pronounced effect on rheology of the suspension. Despite variations in the carbomer concentration, a suspension of comparable rheology could be prepared by controlling the process parameters namely the shear rate and process time.

Modelling integrated antiretroviral treatment and harm reduction services on HIV and overdose among people who inject drugs in Tijuana, Mexico

INTRODUCTION

The HIV epidemic in Tijuana, Mexico is concentrated in key populations, including people who inject drugs (PWID). However, HIV interventions among PWID are minimal, and federal funding was provided for compulsory abstinence programmes associated with HIV and overdose. Alternatively, opioid agonist therapy reduces overdose, reincarceration, HIV, while improving antiretroviral therapy (ART) outcomes. We assessed potential impact and synergies of scaled-up integrated ART and opioid agonist therapy, compared to scale-up of each separately, and potential harms of compulsory abstinence programmes on HIV and fatal overdose among PWID in Tijuana.

METHODS

We developed a dynamic model of HIV transmission and overdose among PWID in Tijuana. We simulated scale-up of opioid agonist therapy from zero to 40% coverage among PWID. We evaluated synergistic benefits of an integrated harm reduction and ART scale-up strategy (40% opioid agonist therapy coverage and 10-fold ART recruitment), compared to scale-up of each intervention alone or no scale-up of low coverage ART and no harm reduction). We additionally simulated compulsory abstinence programmes (associated with 14% higher risk of receptive syringe sharing and 76% higher odds of overdose) among PWID.

RESULTS

Without intervention, HIV incidence among PWID could increase from 0.72 per 100 person-years (PY) in 2020 to 0.92 per 100 PY in 2030. Over ten years, opioid agonist therapy scale-up could avert 31% (95% uncertainty interval (UI): 18%, 46%) and 22% (95% UI: 10%, 28%) new HIV infections and fatal overdoses, respectively, with the majority of HIV impact from the direct effect on HIV transmission due to low ART coverage. Integrating opioid agonist therapy and ART scale-up provided synergistic benefits, with opioid agonist therapy effects on ART recruitment/retention averting 9% more new infections compared to ART scale-up alone. The intervention strategy could avert 48% (95% UI: 26%, 68%) of new HIV infections and one-fifth of fatal overdoses over ten years. Conversely, compulsory abstinence programmes could increase HIV and overdoses.

CONCLUSIONS

Integrating ART with opioid agonist therapy could provide synergistic benefits and prevent HIV and overdoses among PWID in Tijuana, whereas compulsory abstinence programmes could cause harm. Policymakers should consider the benefits of integrating harm reduction and HIV services for PWID.

Longitudinal evaluation of diffusion tensor imaging and cognition in systemic lupus erythematosus

Objective

This pilot study aimed to examine longitudinal changes in brain structure and function in patients with systemic lupus erythematosus (SLE) using diffusion tensor imaging (DTI) and neuropsychological testing.

Methods

Fifteen female SLE patients with no history of major neuropsychiatric (NP) manifestations had brain magnetic resonance imaging (MRI) with DTI at baseline and approximately 1.5 years later. At the same time points, a standardized battery of cognitive tests yielding a global cognitive impairment index (CII) was administered. At baseline, the SLE patients had mean age of 34.0 years (SD = 11.4), mean education of 14.9 years (SD = 2.1), and mean disease duration of 121.5 months (SD = 106.5). The MRI images were acquired with a 3T GE MRI scanner. A DTI sequence with 33 diffusion directions and b-value of 800 s/mm2 was used. Image acquisition time was about 10 minutes.

Results

No significant change in cognitive dysfunction (from the CII) was detected. Clinically evaluated MRI scans remained essentially unchanged, with 62% considered normal at both times, and the remainder showing white matter (WM) hyperintensities that remained stable or resolved. DTI showed decreased fractional anisotropy (FA) and increased mean diffusivity (MD) in bilateral cerebral WM and gray matter (GM) with no major change in NP status, medical symptoms, or medications over time. Lower FA was found in the following regions: left and right cerebral WM, and in GM areas including the parahippocampal gyrus, thalamus, precentral gyrus, postcentral gyrus, angular gyrus, parietal lobe, and cerebellum. Greater MD was found in the following regions: left and right cerebral WM, frontal cortex, left cerebral cortex, and the putamen.

Conclusions

This is the first longitudinal study of DTI and cognition in SLE, and results disclosed changes in both WM and GM without cognitive decline over an 18-month period. DTI abnormalities in our participants were not associated with emergent NP activity, medical decline, or medication changes, and the microstructural changes developed in the absence of macrostructural abnormalities on standard MRI. Microstructural changes may relate to ongoing inflammation, and the stability of cognitive function may be explained by medical treatment, the variability of NP progression in SLE, or the impact of cognitive reserve.

Development and evaluation of an oral fast disintegrating anti-allergic film using hot-melt extrusion technology

The main objective of this novel study was to develop chlorpheniramine maleate orally disintegrating films (ODF) using hot-melt extrusion technology and evaluate the characteristics of the formulation using in vitro and in vivo methods. Modified starch with glycerol was used as a polymer matrix for melt extrusion. Sweetening and saliva-simulating agents were incorporated to improve palatability and lower the disintegration time of film formulations. A standard screw configuration was applied, and the last zone of the barrel was opened to discharge water vapors, which helped to manufacture non-sticky, clear, and uniform films. The film formulations demonstrated rapid disintegration times (6-11s) and more than 95% dissolution in 5min. In addition, the films had characteristic mechanical properties that were helpful in handling and storage. An animal model was employed to determine the taste masking of melt-extruded films. The lead film formulation was subjected to a human panel for evaluation of extent of taste masking and disintegration.

Assessment of Tocilizumab (Anti-Interleukin-6 Receptor Monoclonal) as a Potential Treatment for Chronic Antibody-Mediated Rejection and Transplant Glomerulopathy in HLA-Sensitized Renal Allograft Recipients

Extending the functional integrity of renal allografts is the primary goal of transplant medicine. The development of donor-specific antibodies (DSAs) posttransplantation leads to chronic active antibody-mediated rejection (cAMR) and transplant glomerulopathy (TG), resulting in the majority of graft losses that occur in the United States. This reduces the quality and length of life for patients and increases cost. There are no approved treatments for cAMR. Evidence suggests the proinflammatory cytokine interleukin 6 (IL-6) may play an important role in DSA generation and cAMR. We identified 36 renal transplant patients with cAMR plus DSAs and TG who failed standard of care treatment with IVIg plus rituximab with or without plasma exchange. Patients were offered rescue therapy with the anti-IL-6 receptor monoclonal tocilizumab with monthly infusions and monitored for DSAs and long-term outcomes. Tocilizumab-treated patients demonstrated graft survival and patient survival rates of 80% and 91% at 6 years, respectively. Significant reductions in DSAs and stabilization of renal function were seen at 2 years. No significant adverse events or severe adverse events were seen. Tocilizumab provides good long-term outcomes for patients with cAMR and TG, especially compared with historical published treatments. Inhibition of the IL-6-IL-6 receptor pathway may represent a novel approach to stabilize allograft function and extend patient lives.

JC polyomavirus viremia and progressive multifocal leukoencephalopathy in human leukocyte antigen-sensitized kidney transplant recipients desensitized with intravenous immunoglobulin and rituximab

BACKGROUND

Desensitization (DES) with intravenous immunoglobulin (IVIG) + rituximab is effective, safe, and increases the transplantation rate in human leukocyte antigen-sensitized patients. However, reports of progressive multifocal leukoencephalopathy (PML) caused by JC polyomavirus (JCPyV) in autoimmune patients treated with rituximab is concerning. Here, we report on the JCPyV viremia and PML status in kidney transplant patients with/without DES (non-DES).

METHODS

In total 1195 and 699 DNA samples from plasma in 117 DES (78% lymphocyte-depleting [LyD] induction) and 100 non-DES patients (45% LyD), respectively, were submitted for JCPyV-polymerase chain reaction. Results were compared in both groups.

RESULTS

No patients in either DES or non-DES developed PML or presented with any neurological symptoms. The JCPyV viremia rate was similar in DES and non-DES patients (3/117 vs. 9/100, P = 0.07). The JCPyV levels were low (median peak levels, 1025 copies/mL) and JCPyV viremia was observed only once during the study period in most patients. All 3 DES patients with JCPyV(+) received 1 dose rituximab and no DES patients with >1 dose rituximab showed JCPyV(+). All 3 JCPyV(+) DES patients received LyD induction, while only 2 of 9 JCPyV(+) non-DES patients did so, and the remaining 7 received non-LyD or no induction. JCPyV in leukocyte was mostly negative in DES and non-DES patients. Immunosuppression in patients with or without JCPyV(+) was similar. BK polyomavirus viremia was observed more commonly in patients with JCPyV(+) than in those without (P < 0.02).

CONCLUSIONS

Patients with IVIG + rituximab DES followed by transplantation with LyD induction and additional rituximab rarely show JCPyV viremia and appear at low risk for PML.

The effects of polymer carrier, hot melt extrusion process and downstream processing parameters on the moisture sorption properties of amorphous solid dispersions

OBJECTIVE

The aim of this study was to evaluate the effect of polymer carrier, hot melt extrusion and downstream processing parameters on the water uptake properties of amorphous solid dispersions.

METHODS

Three polymers and a model drug were used to prepare amorphous solid dispersions utilizing the hot melt extrusion technology. The sorption-desorption isotherms of solid dispersions and their physical mixtures were measured by the dynamic vapour sorption system, and the effects of polymer hydrophobicity, hygroscopicity, molecular weight and the hot melt extrusion process were investigated. Fourier transform infrared (FTIR) imaging was performed to understand the phase separation driven by the moisture.

KEY FINDINGS

Solid dispersions with polymeric carriers with lower hydrophilicity, hygroscopicity and higher molecular weight could sorb less moisture under the high relative humidity (RH) conditions. The water uptake ability of polymer-drug solid dispersion systems were decreased compared with the physical mixture after hot melt extrusion, which might be due to the decreased surface area and porosity. The FTIR imaging indicated that the homogeneity of the drug molecularly dispersed within the polymer matrix was changed after exposure to high RH.

CONCLUSION

Understanding the effect of formulation and processing on the moisture sorption properties of solid dispersions is essential for the development of drug products with desired physical and chemical stability.

The femoral head-neck contour varies as a function of physeal development

OBJECTIVES

The purpose of this study was to investigate whether the femoral head-neck contour, characterised by the alpha angle, varies with the stage of physeal maturation using MRI evaluation of an asymptomatic paediatric population.

METHODS

Paediatric volunteers with asymptomatic hips were recruited to undergo MRI of both hips. Femoral head physes were graded from 1 (completely open) to 6 (completely fused). The femoral head-neck contour was evaluated using the alpha angle, measured at the 3:00 (anterior) and 1:30 (anterosuperior) positions and correlated with physeal grade, with gender sub-analysis performed.

RESULTS

A total of 43 asymptomatic paediatric volunteers (26 male, 17 female) with mean age 13.0 years (eight to 18) were included with review of bilateral hip MRIs. Correlation between the physeal grade and alpha angle was moderate in males at both the 3:00 (r = 0.477, p < 0.001) and 1:30 (r = 0.509, p < 0.001) positions, whereas there was no significant correlation in females. A significant difference was found between the alpha angles of all the physeal grades (3:00, p = 0.030, 1:30, p = 0.005), but only in males, with the angle increasing with higher grades. For physeal grading, the inter-reader reliability was substantial (intraclass correlation coefficient (ICC) = 0.694), and the intra-reader reliability was also substantial (ICC = 0.788).

CONCLUSION

The femoral head-neck contour varies and correlates with the stage of physeal development, but only in males, with the alpha angle increasing with progressive physeal maturation. This suggests that gender differences exist in the natural physiological growth, development or remodelling of femoral head-neck junction. In males, pre-physeal fusion may be a critical period of vulnerability for development of morphologic abnormalities of the femoral head-neck junction. Cite this article: Bone Joint Res 2015;4:17-22.

Synaptic signal streams generated by ex vivo neuronal networks contain non-random, complex patterns

Cultured embryonic neurons develop functional networks that transmit synaptic signals over multiple sequentially connected neurons as revealed by multi-electrode arrays (MEAs) embedded within the culture dish. Signal streams of ex vivo networks contain spikes and bursts of varying amplitude and duration. Despite the random interactions inherent in dissociated cultures, neurons are capable of establishing functional ex vivo networks that transmit signals among synaptically connected neurons, undergo developmental maturation, and respond to exogenous stimulation by alterations in signal patterns. These characteristics indicate that a considerable degree of organization is an inherent property of neurons. We demonstrate herein that (1) certain signal types occur more frequently than others, (2) the predominant signal types change during and following maturation, (3) signal predominance is dependent upon inhibitory activity, and (4) certain signals preferentially follow others in a non-reciprocal manner. These findings indicate that the elaboration of complex signal streams comprised of a non-random distribution of signal patterns is an emergent property of ex vivo neuronal networks.

A multicenter phase 1 study of PX-866 in combination with docetaxel in patients with advanced solid tumours

Background:

This phase I, dose-finding study determined the safety, maximum tolerated dose (MTD)/recommended phase 2 dose (RP2D), pharmacokinetics, and antitumour activity of PX-866, a phosphatidylinositol 3-kinase inhibitor, combined with docetaxel in patients with incurable solid tumours.

Methods:

PX-866 was administered at escalating doses (4–8 mg daily) with docetaxel 75 mg m⁻² intravenously every 21 days. Archived tumour tissue was assessed for potential predictive biomarkers.

Results:

Forty-three patients were enrolled. Most adverse events (AEs) were grade 1 or 2. The most frequent study drug-related AE was diarrhoea (76.7%), with gastrointestinal disorders occurring in 79.1% (docetaxel-related) and 83.7% (PX-866-related). No dose-limiting toxicities were observed. The RP2D was 8 mg, the same as the single-agent MTD. Co-administration of PX-866 and docetaxel did not affect either drug's PKs. Best responses in 35 evaluable patients were: 2 partial responses (6%), 22 stable disease (63%), and 11 disease progression (31%). Eleven patients remained on study for >180 days, including 8 who maintained disease control on single-agent PX-866. Overall median progression-free survival (PFS) was 73.5 days (range: 1–569). A non-significant association between longer PFS for PIK3CA-MUT/KRAS-WT vs PIK3CA-WT/KRAS-WT was observed.

Conclusion:

Treatment with PX-866 and docetaxel was well tolerated, without evidence of overlapping/cumulative toxicity. Further investigation with this combination is justified.

The onset of rapidly progressive neurologic deterioration after a brief gastrointestinal illness in a renal allograft recipient

Renal transplant recipients are at increased risk for life-threatening complications, most commonly infections. Because of their impaired cell-mediated immunity, these patients are particularly susceptible to organisms that rely on intracellular survival and spread, such as Listeria monocytogenes. Despite being a food-borne pathogen, L. monocytogenes is associated with significant morbidity and mortality. Here we report the case of a renal transplant recipient who developed rapidly progressive neurological symptoms after a brief gastrointestinal illness. Magnetic resonance imaging scan of the brain showed a large mass that was identified as an abscess due to L. monocytogenes. Timely aspiration and antibiotic treatment resulted in complete recovery, as opposed to worse outcomes in the available case reports. We further review the epidemiology, microbiology, clinical presentation, and therapeutic options for listerial brain abscess.

Successful use of oral ganciclovir for the treatment of intrauterine cytomegalovirus infection in a renal allograft recipient

Congenital cytomegalovirus (CMV) infection occurs in approximately 1% of newborns and is the leading infectious cause of congenital birth defects. Female renal allograft recipients who develop CMV infection during pregnancy are at risk for both graft dysfunction and fetal morbidity. DNA-based analysis of amniotic fluid (AF) from at-risk pregnancies has been suggested as an adjunct/substitute for traditional culture. We have shown that CMV-polymerase chain reaction of AF is a useful diagnostic test for congenital CMV infection. Using this test we diagnosed CMV infection in the fetus of a 30-year-old renal transplant recipient. As termination was not an option for the family, the patient was extensively counseled and treated with oral ganciclovir. This resulted in clearance of the virus from the AF and the delivery of a healthy newborn girl, free of CMV disease. This is the first reported case to our knowledge of successful use of maternal ganciclovir to treat intrauterine CMV infection in a pregnant renal transplant recipient.

Reactive oxygen species promote tyrosine phosphorylation and capacitation in equine spermatozoa

The objective of this study was to examine the influence of reactive oxygen species (ROS) on equine sperm capacitation. Motile equine spermatozoa were separated on a discontinuous Percoll gradient, resuspended at 10 x 10(6)ml in Tyrode's medium supplemented with BSA (0.5%) and polyvinyl alcohol (0.5%) and incubated at 39 degrees C for 2h with or without the xanthine (X; 0.1mM)-xanthine oxidase (XO; 0.01 U/ml) system or NADPH (0.25 mM). The importance of hydrogen peroxide or superoxide for capacitation was determined by the addition of catalase (CAT; 150 U/ml) or superoxide dismutase (SOD; 150 U/ml), respectively. Following incubation, acrosomal exocytosis was induced by a 5 min incubation at 39 degrees C with progesterone (3.18 microM), and sperm viability and acrosomal integrity were then determined by staining with Hoechst 33258 and fluoroisothiocyanate-conjugated Pisum sativum agglutin. To examine tyrosine phosphorylation, treatments were subjected to sodium dodecyl sulfate-polyacrylaminde gel electrophoresis (SDS-PAGE) followed by Western blot analysis with the anti-phosphotyrosine antibody (alpha-PY; clone 4G10). Capacitation with the X-XO system or NADPH led to a significant (P<0.0001) increase in live acrosome-reacted spermatozoa compared to controls. The addition of CAT or SOD prevented the increase in live acrosome-reacted spermatozoa associated with X-XO treatment. Incubation with the X-XO system was also associated with a significant (P<0.005) increase in tyrosine phosphorylation when compared to controls, which could be prevented by the addition of CAT but not SOD. This study indicates that ROS can promote equine sperm capacitation and tyrosine phosphorylation, suggesting a physiological role for ROS generation by equine spermatozoa.

Intravenous immune globulin treatment inhibits crossmatch positivity and allows for successful transplantation of incompatible organs in living-donor and cadaver recipients

BACKGROUND

Sensitization to human leukocyte antigens (HLA) is a significant barrier to transplantation. Currently, no proven therapy exists to improve access to transplantation for highly sensitized patients. Here, we report a novel approach using intravenous immune globulin to modulate anti-HLA antibody and improve the chances for successful transplantation.

PATIENTS AND METHODS

Forty-five highly HLA-sensitized patients presented as candidates for living-donor kidney transplantation (n=28), cadaveric kidney transplantation (n=15), or heart transplantation (n=2). All patients had a positive CDC crossmatch (CMX) with their donors. In living-donor recipients, intravenous immune globulin (IVIG) was added to the CMX evaluation to determine whether blocking antibodies present in IVIG could inhibit cytotoxicity. For those who showed in vitro inhibition with IVIG (n=26), IVIG was administered (usually as a single dose, 2 g/kg) and the CDC CMX was repeated against the prospective donor immediately after IVIG infusion. If negative, the patient underwent transplantation with their living-donor kidney within 24 to 72 hr. A similar but modified protocol was performed for cadaver donor candidates, all of whom were highly sensitized and had had CMX positivity with multiple donors, negating transplantation. Reductions in CMX positivity, posttransplantation serum creatinine level, number and severity of rejection episodes, and patient and graft survival rates were determined.

RESULTS

Forty-two patients underwent transplantation. IVIG treatment completely abrogated the donor-specific CMXs in 35 of 42 patients. In the remaining 7 patients, the CDC CMX was inhibited, but flow cytometry CMXs remained positive. A total of 13 (31%) of 42 recipients developed rejection episodes 3 to 49 days after transplantation. Three grafts (7%) were lost to rejection. Mean serum creatinine level at 24 months was 1.4+/-0.4 mg/dL. Patient and graft survival rates were 97.6% and 89.1%, respectively, at 24 months.

CONCLUSIONS

The in vitro IVIG CMX technique predicts the ability of IVIG to reduce anti-HLA antibody levels in highly sensitized patients. Subsequent in vivo IVIG treatment of responders eliminates the positive CDC CMX and allows for successful transplantation. Thus a positive CMX result is not necessarily a contraindication for transplantation and allows access to transplantation for patients for whom it was previously contraindicated.