Rapid Delivery of Diazepam from Supersaturated Solutions Prepared Using Prodrug/Enzyme Mixtures: Toward Intranasal Treatment of Seizure Emergencies

Current treatments for seizure emergencies, such as status epilepticus, include intravenous or rectal administration of benzodiazepines. While intranasal delivery of these drugs is desirable, the small volume of the nasal cavity and low drug solubility pose significant difficulties. Here, we prepared supersaturated diazepam solutions under physiological conditions and without precipitation, using a prodrug/enzyme system. Avizafone, a peptide prodrug of diazepam, was delivered with—Aspergillus oryzae (A.O.) protease, an enzyme identified from a pool of hydrolytic enzymes in assay buffer, pH 7.4 at 32°C. This enzyme converted avizafone to diazepam at supersaturated concentrations. In vitro permeability studies were performed at various prodrug/enzyme ratios using Madin-Darby canine kidney II-wild type (MDCKII-wt) monolayers, a representative model of the nasal epithelium. Monolayer integrity was examined using TEER measurement and the lucifer yellow permeability assay. Prodrug/drug concentrations were measured using HPLC. Enzyme kinetics with avizafone-protease mixtures revealed K_M = 1,501 ± 232 μM and V_max = 1,369 ± 94 μM/s. Prodrug-protease mixtures, when co-delivered apically onto MDCKII-wt monolayers, showed 2–17.6-fold greater diazepam flux (S = 1.3–15.3) compared to near-saturated diazepam (S = 0.7). Data for prodrug conversion upstream (apical side) and drug permeability downstream (basolateral side) fitted reasonably well to a previously developed in vitro two compartment pharmacokinetic model. Avizafone-protease mixtures resulted in supersaturated diazepam in less than 5 min, with the rate and extent of supersaturation determined by the prodrug/enzyme ratio. Together, these results suggest that an intranasal avizafone-protease system may provide a rapid and alternative means of diazepam delivery.

Electronic supplementary material

The online version of this article (doi:10.1208/s12248-014-9596-5) contains supplementary material, which is available to authorized users.KEY WORDS: avizafone enzyme activation, diazepam delivery, hydrophobic drugs, MDCK monolayers, rapid absorption, seizure emergencies, supersaturation     

Use of BioGlue Surgical Adhesive in Hypospadias Repair

Purpose

To prospectively evaluate the efficacy of albumin glutaraldehyde tissue adhesive (BioGlue) in the surgical treatment of patients with hypospadias.

Materials and Methods

Two groups of 20 patients each who underwent hypospadias repair were included in the study. In the first group we utilized BioGlue as an additional protective layer to the suture line of the neo-urethra, while patients in the second group were operated on utilizing a routine surgical technique.

Results

There were no statistical differences between patients from the 2 groups in terms of surgical complications. Urethrocutaneous fistula was revealed in 4 (20%) patients after repair with BioGlue and in 3 (15%) patients from the control group (p = 0.686), suture line breakdown in 4 (20%) and in 1 (5%) patients (p = 0.478), meatal stenosis in 1 (5%) and in 1 (5%) patient (p = 1). Furthermore more patients in the BioGlue group (n = 12, 60%) demonstrated poor cosmetic results compared to the control group where most patients – 19 (95%) had acceptable cosmetic outcomes (p = 0.007).

Conclusions

Our data showed no benefits of BioGlue use in hypospadias repair.Key Words: Hypospadias, BioGlue, Hypospadias repair, Urethrocutaneous fstula     

Biphasic transmittance waveform in the APTT coagulation assay is due to the formation of a Ca(++)-dependent complex of C-reactive protein with very-low-density lipoprotein and is a novel marker of impending disseminated intravascular coagulation

A decrease in light transmittance before clot formation, manifesting as a biphasic waveform (BPW) pattern in coagulation assays, was previously correlated with the onset of disseminated intravascular coagulation (DIC). In this study of 1187 consecutive admissions to the intensive care unit, the degree of this change on admission predicts DIC better than D-dimer measurements. Additionally, the BPW preceded the time of DIC diagnosis by 18 hours, on average, in 56% (203 of 362) of DIC patients. The BPW is due to the rapid formation of a precipitate and coincident turbidity change on recalcification of plasma. The isolated precipitate contains very-low-density lipoprotein (VLDL) and C-reactive protein (CRP). The addition of CRP and Ca(++) to normal plasma also causes the precipitation of VLDL and IDL, but not LDL or HDL. The K(d) of the CRP/VLDL interaction is 340 nM, and the IC(50) for Ca(++) is 5.0 mM. In 15 plasmas with the BPW, CRP was highly elevated (77-398 microg/mL), and the concentration of isolated VLDL ranged from 0.082 to 1.32 mM (cholesterol). The turbidity change on recalcification correlates well with the calculated level of the CRP-VLDL complex. Clinically, the BPW better predicts for DIC than either CRP or triglyceride alone. The complex may have pathophysiological implications because CRP can be detected in the VLDL fraction from sera of patients with the BPW, and the VLDL fraction has enhanced prothrombinase surface activity. The complex has been designated lipoprotein complexed C-reactive protein.     

Expansion of the spectrum of TUBB4A-related disorders: a new phenotype associated with a novel mutation in the TUBB4A gene

Mutations in the TUBB4A gene have been identified so far in two neurodegenerative disorders with extremely different clinical features and course: whispering dysphonia, also known as dystonia type 4 (DYT4), and hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC). We describe a patient with slowly progressive spastic paraparesis, segmental dystonia, intellectual disability, behavioral problems, and evidence of permanent, incomplete myelination associated with progressive cerebellar atrophy. Whole exome sequencing revealed a novel E410K de novo heterozygous mutation in the TUBB4A gene. The clinical and radiological picture of our patient is different from the classic phenotype; thus, it expands the phenotypic variation of TUBB4A-gene-related disorders.     

Bilateral polymicrogyria associated with dystonia: A new neurogenetic syndrome?

The clinical presentation of bilateral perisylvian polymicrogyria (PMG) is highly variable, including oromotor dysfunction, epilepsy, intellectual disability, and pyramidal signs. Extrapyramidal features are extremely rare. We present four apparently unrelated patients with a unique association of PMG with dystonia. The clinical, genetic, and radiologic features are described and possible mechanisms of dystonia are discussed. All patients were female and two were born to consanguineous families. All presented with early childhood onset dystonia. Other neurologic symptoms and signs classically seen in bilateral perisylvian PMG were observed, including oromotor dysfunction and speech abnormalities ranging from dysarthria to anarthria (4/4), pyramidal signs (3/4), hypotonia (3/4), postnatal microcephaly (1/4), and seizures (1/4). Neuroimaging showed a unique pattern of bilateral PMG with an infolded cortex originating primarily from the perisylvian region in three out of four patients. Whole exome sequencing was performed in two out of four patients and did not reveal pathogenic variants in known genes for cortical malformations or movement disorders. The dystonia seen in our patients is not described in bilateral PMG and suggests an underlying mechanism of impaired connectivity within the motor network or compromised cortical inhibition. The association of bilateral PMG with dystonia in our patients may represent a new neurogenetic disorder.     

Disturbed B and T cell homeostasis and neogenesis in patients with ataxia telangiectasia

Objective

Ataxia telangiectasia (AT) is a rare genetic, multi-system disorder characterized by neurodegeneration, chromosome instability, B and T cell immunodeficiency and a predisposition to cancer. We examined immunologic parameters reflecting cell development and proliferation and their relevancy to the clinical phenotype in affected individuals.

Patients and Methods

AT patients from the AT National Clinic in Israel underwent immunological investigation. Their T and B cell workup included lymphocyte subset counts, immunoglobulin levels, responses to mitogenic stimulations, TCR-Vβ families and BCR immunoglobulin heavy chain spectratyping, TCR rearrangement excision circles (TRECs) and Kappa-deleting recombination excision circles (KRECs).

Results

Thirty-seven AT patients (median age 12.7 years, range 4.2–25.1) were evaluated. CD20 B and CD3 T lymphocytes were decreased in 67 % and 64 % of the patients, respectively, while only 33 % of the patients had reduced lymphoproliferative responses. Almost all AT patients displayed extremely low TRECs and KRECs levels, irrespective of their age. Those levels were correlated to one another and to the amounts of CD3+ and CD20+ cells, respectively. Abnormal TCR-Vβ repertoires were found with different degrees of clonality or reduced expression in these AT patients. There was no clear clustering of expansions to specific TCR-Vβ genes. PCR spectratyping analysis of the FR2 IgH BCR gene rearrangements in peripheral blood was abnormal in 50 % of the patients.

Conclusion

The immunodeficiency associated with AT is combined, remains low over time and not progressive. It is characterized by low TREC and KREC copies suggestive of abnormal T and B cell neogenesis.     

Estrogen receptor alpha and androgen receptor are commonly expressed in well-differentiated liposarcoma

Background

Liposarcoma (LS) is the second-most common type of soft-tissue sarcoma. Despite advances in knowledge and treatment of this disease, there remains a need for more effective LS therapy. Steroid hormone receptors regulate metabolism in adipocytes. Estrogen receptor alpha (ER), progesterone receptor (PR), and androgen receptor (AR) have been implicated in the pathophysiology of other cancer types. We sought to comprehensively determine temporal expression patterns of these receptors in LS.

Methods

We analyzed 561 histologically subtyped LS specimens from 354 patients for expression of ER, PR, and AR by immunohistochemistry (IHC) using diagnostic-grade reagents and protocols. The fractions of positively stained tumor cells were scored within each specimen. IHC scores were compared across LS subtypes using the Kruskal-Wallis test, and subtypes were compared using Dunn’s post-hoc test. Ages of patients with receptor-positive vs. -negative LS were compared by t-test. Genders and races were compared for hormone receptor positivity using Fisher’s exact test and Chi-square analysis, respectively. Recurrence-free survival was compared between receptor-positive and negative patients by log-rank test. p<?0.05 was considered significant.

Results

ER and AR were frequently expressed in LS, while few tumors expressed PR. Most of the ER?+?and AR?+?samples were of the well-differentiated LS subtype. A smaller fraction of de-differentiated LS expressed ER or AR, but expression was common within well-differentiated regions of tumors histologically classified as de-differentiated LS. In LS specimens from patients who underwent multiple surgeries over time, receptor expression frequently changed over time, which may be attributable in part to intratumor heterogeneity, varying degrees of de-differentiation, and biopsy bias. ER and AR were frequently co-expressed. Receptor status was not significantly associated with gender or race, but AR and PR expression were associated with earlier age at diagnosis. Receptor expression was not associated with altered recurrence-free survival.

Conclusions

ER and AR are commonly expressed in LS, particularly in well-differentiated tumors. These data warrant further functional study to determine receptor function in LS, and the potential efficacy of anti-hormone therapies for the treatment of patients with LS.