Nasal ciliary motility: a new tool in estimating the time of death

The nose as a feature of forensic practice

The nose is a prominent facial structure which is too often overlooked by forensic medicine practitioners. Studies that consider the role of the nose in forensic practice are scattered throughout scientific literature. We provide a brief review of these.

Convolutions in the rendition of nose to brain therapeutics from bench to bedside: Feats & fallacies

Brain, a subtle organ of multifarious nature presents plethora of physiological, metabolic and bio-chemical convolutions that impede the delivery of biomolecules and thereby resulting in truncated therapeutic outcome in pathological conditions of central nervous system (CNS). The absolute bottleneck in the therapeutic management of such devastating CNS ailments is the BBB. Another pitfall is the lack of efficient technological platforms (due to high cost and low approval rates) as well as limited clinical trials (due to failures of neuro‑leads in late-stage pipelines) for CNS disorders which has become a literal brain drain with poorest success rates compared to other therapeutic areas, owing to time consuming processes, tremendous convolutions and conceivable adverse effects. With the advent of intranasal delivery (via direct N2B or indirect nose to blood to brain), several novel drug delivery carriers viz. unmodified or surface modified nanoparticle based carriers, lipid based colloidal nanocarriers and drysolid/liquid/semisolid nanoformulations or delivery platforms have been designed as a means to deliver therapeutic agents (small and large molecules, peptides and proteins, genes) to brain, bypassing BBB for disorders such as Alzheimer's disease (AD), Parkinson's disease (PD), epilepsy, schizophrenia and CNS malignancies primarily glioblastomas. Intranasal application offers drug delivery through both direct and indirect pathways for the peripherally administered psychopharmacological agents to CNS. This route could also be exploited for the repurposing of conventional drugs for new therapeutic uses. The limited clinical translation of intranasal formulations has been primarily due to existence of barriers of mucociliary clearance in the nasal cavity, enzyme degradation and low permeability of the nasal epithelium. The present review literature aims to decipher the new paradigms of nano therapeutic systems employed for specific N2B drug delivery of CNS drugs through in silico complexation studies using rationally chosen mucoadhesive polymers (exhibiting unique physicochemical properties of nanocarrier's i.e. surface modification, prolonging retention time in the nasal cavity, improving penetration ability, and promoting brain specific delivery with biorecognitive ligands) via molecular docking simulations. Further, the review intends to delineate the feats and fallacies associated with N2B delivery approaches by understanding the physiological/anatomical considerations via decoding the intranasal drug delivery pathways or critical factors such as rationale and mechanism of excipients, affecting the permeability of CNS drugs through nasal mucosa as well as better efficacy in terms of brain targeting, brain bioavailability and time to reach the brain. Additionally, extensive emphasis has also been laid on the innovative formulations under preclinical investigation along with their assessment by means of in vitro /ex vivo/in vivo N2B models and current characterization techniques predisposing an efficient intranasal delivery of therapeutics. A critical appraisal of novel technologies, intranasal products or medical devices available commercially has also been presented. Finally, it could be warranted that more reminiscent pharmacokinetic/pharmacodynamic relationships or validated computational models are mandated to obtain effective screening of molecular architecture of drug-polymer-mucin complexes for clinical translation of N2B therapeutic systems from bench to bedside.

Nanotherapeutics for Nose-to-Brain Drug Delivery: An Approach to Bypass the Blood Brain Barrier

Treatment of neurodegenerative diseases or other central nervous system (CNS) disorders has always been a significant challenge. The nature of the blood-brain barrier (BBB) limits the penetration of therapeutic molecules to the brain after oral or parenteral administration, which, in combination with hepatic metabolism and drug elimination and inactivation during its journey in the systemic circulation, decreases the efficacy of the treatment, requires high drug doses and often induces adverse side effects. Nose-to-brain drug delivery allows the direct transport of therapeutic molecules by bypassing the BBB and increases drug concentration in the brain. The present review describes mechanisms of nose-to-brain drug delivery and discusses recent advances in this area with especial emphasis on nanotechnology-based approaches.

Pre-Clinical Assessment of the Nose-to-Brain Delivery of Zonisamide After Intranasal Administration

PURPOSE

Zonisamide clinical indications are expanding beyond the classic treatment of epileptic seizures to Parkinson's disease and other neurodegenerative diseases. However, the systemic safety profile of zonisamide may compromise its use as a first-line drug in any clinical condition. Since zonisamide is marketed as oral formulations, the present study aimed at exploring the potential of the intranasal route to centrally administer zonisamide, evaluating the systemic bioavailability of zonisamide and comparing its brain, lung and kidney pharmacokinetics after intranasal, oral and intravenous administrations.

METHODS

In vitro cell studies demonstrated that zonisamide and proposed thermoreversible gels did not affect the viability of RPMI 2650 or Calu-3 cells. Thereafter, male CD-1 mice were randomly administered with zonisamide by oral (80 mg/kg), intranasal or intravenous (16.7 mg/kg) route. At predefined time points, animals were sacrificed and plasma and tissues were collected to quantify zonisamide and describe its pharmacokinetics.

RESULTS

Intranasal route revealed a low absolute bioavailability (54.95%) but the highest value of the ratio between the area under the curve (AUC) between brain and plasma, suggesting lower systemic adverse events and non-inferior effects in central nervous system comparatively to intravenous and oral routes. Furthermore, drug targeting efficiency and direct transport percentage into the brain were 149.54% and 33.13%, respectively, corroborating that a significant fraction of zonisamide suffers direct nose-to-brain transport. Lung and kidney exposures obtained after intranasal administration were lower than those observed after intravenous injection.

CONCLUSIONS

This pre-clinical investigation demonstrates a direct nose-to-brain delivery of zonisamide, which may be a promising strategy for the treatment of central diseases.

Tailoring Formulations for Intranasal Nose-to-Brain Delivery: A Review on Architecture, Physico-Chemical Characteristics and Mucociliary Clearance of the Nasal Olfactory Mucosa

The blood-brain barrier and the blood-cerebrospinal fluid barrier are major obstacles in central nervous system (CNS) drug delivery, since they block most molecules from entering the brain. Alternative drug delivery routes like intraparenchymal or intrathecal are invasive methods with a remaining risk of infections. In contrast, nose-to-brain delivery is a minimally invasive drug administration pathway, which bypasses the blood-brain barrier as the drug is directed from the nasal cavity to the brain. In particular, the skull base located at the roof of the nasal cavity is in close vicinity to the CNS. This area is covered with olfactory mucosa. To design and tailor suitable formulations for nose-to-brain drug delivery, the architecture, structure and physico-chemical characteristics of the mucosa are important criteria. Hence, here we review the state-of-the-art knowledge about the characteristics of the nasal and, in particular, the olfactory mucosa needed for a rational design of intranasal formulations and dosage forms. Also, the information is suitable for the development of systemic or local intranasal drug delivery as well as for intranasal vaccinations.

Nasal cytology: Methodology with application to clinical practice and research

Nasal cytology is an easy, cheap, non-invasive and point-of-care method to assess nasal inflammation and disease-specific cellular features. By means of nasal cytology, it is possible to distinguish between different inflammatory patterns that are typically associated with specific diseases (ie, allergic and non-allergic rhinitis). Its use is particularly relevant when other clinical information, such as signs, symptoms, time-course and allergic sensitizations, is not enough to recognize which of the different rhinitis phenotypes is involved; for example, it is only by means of nasal cytology that it is possible to distinguish, among the non-allergic rhinitis, those characterized by eosinophilic (NARES), mast cellular (NARMA), mixed eosinophilic-mast cellular (NARESMA) or neutrophilic (NARNE) inflammation. Despite its clinical usefulness, cheapness, non-invasiveness and easiness, nasal cytology is still underused and this is at least partially due to the fact that, as far as now, there is not a consensus or an official recommendation on its methodological issues. We here review the scientific literature about nasal cytology, giving recommendations on how to perform and interpret nasal cytology.

Association of Inflammatory Status and Maxillary Sinus Schneiderian Membrane Thickness

OBJECTIVES

Certain Schneiderian membrane thicknesses (SMT) have shown to be more prone to tearing/perforation, and some pathologies might influence SMT. Henceforth, we aimed at studying the correlation of inflammatory status to SMT in human fresh cadaver heads.

MATERIAL AND METHODS

A total of 14 fresh cadaver heads including 27 Schneiderian membrane specimens were histologically collected. A 10-item inflammatory score was determined in the entire sample and also in the thinner and thicker areas of each sample. Data was analyzed by using the Wilcoxon rank test and the Spearman's rank correlation.

RESULTS

The mean measured SMT was 0.40 ± 0.12 mm and the median was 0.33 ± 0.12 mm. A weak positive correlation was found between the mean SMT and inflammation score without a statistical significance. (r = 0.385, p = 0.115). The Wilcoxon signed-rank test showed a statistical difference between the medians of the thinner and thicker areas (p < 0.001). The mean inflammation score of the thinner and thicker areas was 8.55 ± 2.57 and 11.61 ± 2.65, respectively. A moderate positive and statistically significant correlation was found between the inflammation score and the thickness of the thinner and thicker areas (r = 0.638, p = 0.000).

CONCLUSION

A moderate association between the Schneiderian membrane thickness and the level of inflammation exists.

Accurate predictions of postmortem interval using linear regression analyses of gene meter expression data

In criminal and civil investigations, postmortem interval is used as evidence to help sort out circumstances at the time of human death. Many biological, chemical, and physical indicators can be used to determine the postmortem interval - but most are not accurate. Here, we sought to validate an experimental design to accurately predict the time of death by analyzing the expression of hundreds of upregulated genes in two model organisms, the zebrafish and mouse. In a previous study, the death of healthy adults was conducted under strictly controlled conditions to minimize the effects of confounding factors such as lifestyle and temperature. A total of 74,179 microarray probes were calibrated using the Gene Meter approach and the transcriptional profiles of 1063 genes that significantly increased in abundance were assembled into a time series spanning from life to 48 or 96h postmortem. In this study, the experimental design involved splitting the transcription profiles into training and testing datasets, randomly selecting groups of profiles, determining the modeling parameters of the genes to postmortem time using over- and/or perfectly-defined linear regression analyses, and calculating the fit (R²) and slope of predicted versus actual postmortem times. This design was repeated several thousand to million times to find the top predictive groups of gene transcription profiles. A group of eleven zebrafish genes yielded R² of 1 and a slope of 0.99, while a group of seven mouse liver genes yielded a R² of 0.98 and a slope of 0.97, and seven mouse brain genes yielded a R² of 0.95 and a slope of 0.87. In all cases, groups of gene transcripts yielded better postmortem time predictions than individual gene transcripts. The significance of this study is two-fold: selected groups of gene transcripts provide accurate prediction of postmortem time, and the successfully validated experimental design can now be used to accurately predict postmortem time in cadavers.

Postmortem Changes in Animal Carcasses and Estimation of the Postmortem Interval

A thorough understanding of the physical and chemical changes that occur in the body after death is critical for accurate interpretation of gross and microscopic pathology at autopsy. Furthermore, knowledge of the postmortem processes and the factors that affect them will aid in the estimation of the postmortem interval (PMI). The estimation of the PMI is important in many human and animal death investigations. Despite many decades of research, accuracy in estimation of the time of death has not significantly improved, and no single method can be reliably used to accurately estimate the time of death. Great care should be taken when formulating such an estimate, for it is dependent on multiple circumstantial and environmental factors, and the accuracy and precision of the estimate decrease as the PMI increases. The majority of the research in the field has been conducted on human bodies, but many relevant conclusions may be drawn regarding the expected postmortem changes in animals and the estimation of the PMI. The veterinary pathologist must use great caution when attempting to extrapolate data and apply formulas designed for use in humans. Methods reviewed include gross changes, microscopic changes, temperature-based methods, postmortem chemistry, molecular methods, microbial assay, ocular changes, radiography, entomology, and others. Although only several of these methods are currently practical for use in the workup of cases, it is expected that future research will result in improved techniques with enhanced accuracy in the estimation of the PMI, which will benefit both human and veterinary forensic investigations.

Effect of Radiofrequency Thermal Ablation Treatment on Nasal Ciliary Motility: A Study with Phase-Contrast Microscopy

OBJECTIVE

To investigate the efficacy of nasal ciliary motility after radiofrequency ablation treatment in patients with isolated inferior turbinate hypertrophy and to clarify how long until normal ciliary function is restored.

STUDY DESIGN

Prospective, single-group, pretest-posttest design.

SETTING

Academic tertiary care medical center.

SUBJECTS AND METHODS

This study involved 34 adult patients affected by nasal obstruction due to inferior turbinate hypertrophy who underwent radiofrequency ablation treatment between June and December 2014. Diagnosis was assessed according to clinical history, nasal endoscopy, and active anterior rhinomanometry. Cytologic samples were collected by nasal scraping before surgery and 1, 2, and 3 months after surgery. Ciliary motility was evaluated by nasal cytology with phase-contrast microscopy. Functional aspects of nasal mucosa were studied, with a focus on 3 parameters: (1) nasal mucociliary clearance, assessed by saccharin nasal transit time test; (2) percentage of ciliated cell motility, measured as the ratio between cells with motility and cells without motility; and (3) efficacy of ciliary motility, measured as the ratio between cells with valid motility and cells with hypovalid motility.

RESULTS

Ciliary motility and ciliary efficacy showed a significant reduction after 1 and 2 months from surgery, returning to normal values within 3 months. No significant changes in saccharin nasal transit time were recorded during the follow-up.

CONCLUSIONS

The outcomes of this study suggest that radiofrequency ablation treatment causes ciliary motility changes of nasal mucosa that are completely restored after at least 3 months after surgery. These cytologic abnormalities do not affect nasal functionality.

Cytologic and functional alterations of nasal mucosa in smokers: temporary or permanent damage?

OBJECTIVE

Tobacco smoke is a significant risk factor for respiratory diseases. The purpose of this study is to analyze the cytologic and functional features of nasal mucosa in smokers, nonsmokers, and ex-smokers to evaluate if nasal alterations in smokers are permanent or reversible conditions after smoking cessation.

STUDY DESIGN

Case series with planned data collection.

SETTING

University medical center.

SUBJECTS AND METHODS

Ninety healthy volunteers recruited from the staff of Alfredo Fiorini Hospital, Sapienza University of Rome, were enrolled in this prospective study from October to November 2013. We divided the cases according to smoking habits (smokers, nonsmokers, ex-smokers). Each group was composed of 30 subjects. Cytologic features of nasal mucosa and effectiveness of nasal mucociliary clearance were studied, focusing on 4 parameters: (1) nasal mucociliary clearance, assessed by saccharin nasal transit time; (2) ratio between the number of ciliated cells and goblet cells, analyzed by microscopic observation of cytologic specimens of nasal mucosa that had undergone May Grunwald Giemsa staining; (3) evaluation of ciliary motility; and (4) time of ciliary movement of ciliated cells analyzed by phase-contrast microscopy.

RESULTS

All parameters were significantly reduced in the smokers compared to the nonsmokers. There were no statistically significant differences between the nonsmoker and ex-smoker groups.

CONCLUSION

Cigarette smoking causes cytologic modifications of nasal mucosa that influence the effectiveness of mucociliary clearance. Our preliminary study suggests that these changes are not permanent and that nasal mucosa of ex-smokers recovers normal cytologic and functional features.

Cilia dysfunction in lung disease

A characteristic feature of the human airway epithelium is the presence of ciliated cells bearing motile cilia, specialized cell surface projections containing axonemes composed of microtubules and dynein arms, which provide ATP-driven motility. In the airways, cilia function in concert with airway mucus to mediate the critical function of mucociliary clearance, cleansing the airways of inhaled particles and pathogens. The prototypical disorder of respiratory cilia is primary ciliary dyskinesia, an inherited disorder that leads to impaired mucociliary clearance, to repeated chest infections, and to the progressive destruction of lung architecture. Numerous acquired lung diseases are also marked by abnormalities in both cilia structure and function. In this review we summarize current knowledge regarding airway ciliated cells and cilia, how they function to maintain a healthy epithelium, and how disorders of cilia structure and function contribute to inherited and acquired lung disease.