Calreticulin accelerates corneal wound closure and mitigates fibrosis: Potential therapeutic applications.

The processes involved in regeneration of cutaneous compared to corneal tissues involve different intrinsic mechanisms. Importantly, cutaneous wounds involve healing by angiogenesis but vascularization of the cornea obscures vision. Previous studies showed that topically applied calreticulin (CALR) healed full-thickness excisional animal wounds by a tissue regenerative process markedly enhancing repair without evoking angiogenesis. In the current study, the application of CALR in a rabbit corneal injury model: (1) accelerated full wound closure by 3 days (2) accelerated delayed healing caused by corticosteroids, routinely used to prevent post-injury inflammation, by 6 days and (3) healed wounds without vascularization or fibrosis/hazing. In vitro, CALR stimulated proliferation of human corneal epithelial cells (CE) and corneal stromal cells (keratocytes) by 1.5-fold and 1.4-fold, respectively and induced migration of CE cells and keratocytes, by 72% and 85% compared to controls of 44% and 59%, respectively. As a marker of decreased fibrosis, CALR treated corneal wounds showed decreased immunostaining for α-smooth muscle actin (α-SMA) by keratocytes and following CALR treatment in vitro, decreased the levels of TGF-ß2 in human CE cells and α-SMA in keratocytes. CALR has the potential to be a novel therapeutic both, to accelerate corneal healing from various injuries and in conjunction with corticosteroids.

Epigenetic regulons in Alzheimer's disease.

Alzheimer's disease is one of the most prevalent forms of dementia that occur genetically or sporadically (with increasing age) in the population of 65 years and above. The pathological hallmarks of AD include the formation of extracellular senile plaques of amyloid beta peptides 42 (Aß42) and intracellular neurofibrillary tangles associated with hyperphosphorylated tau protein. AD has been reported as an outcome of multiple probabilistic factors such as age, lifestyle, oxidative stress, inflammation, insulin resistance, mitochondrial dysfunction, and epigenetics. Epigenetics are heritable changes in gene expression that give a phenotype without altering the DNA sequences. Epigenetic mechanisms include DNA methylation, hydroxymethylation, histone modifications, regulation of miRNAs and long non-coding RNAs, which are reported to be dysregulated in AD. Further, epigenetic mechanisms have been shown as a key player as they regulate memory development, where DNA methylation and post-translational modifications of histone tails are the prime epigenetic markers. Also, alterations of AD-related genes cause pathogenesis on the transcriptional level. In the current chapter, we summarize the role of epigenetics in the onset and progression of AD and the use of epigenetic therapeutics to ameliorate the constraints of AD.

Epigenetic control of heredity.

Epigenetics is the field of science that deals with the study of changes in gene function that do not involve changes in DNA sequence and are heritable while epigenetics inheritance is the process of transmission of epigenetic modifications to the next generation. It can be transient, intergenerational, or transgenerational. There are various epigenetic modifications involving mechanisms such as DNA methylation, histone modification, and noncoding RNA expression, all of which are inheritable. In this chapter, we summarize the information on epigenetic inheritance, its mechanism, inheritance studies on various organisms, factors affecting epigenetic modifications and their inheritance, and the role of epigenetic inheritance in the heritability of diseases.

Aging: Epigenetic modifications.

Aging is one of the most complex and irreversible health conditions characterized by continuous decline in physical/mental activities that eventually poses an increased risk of several diseases and ultimately death. These conditions cannot be ignored by anyone but there are evidences that suggest that exercise, healthy diet and good routines may delay the Aging process significantly. Several studies have demonstrated that Epigenetics plays a key role in Aging and Aging-associated diseases through methylation of DNA, histone modification and non-coding RNA (ncRNA). Comprehension and relevant alterations in these epigenetic modifications can lead to new therapeutic avenues of age-delaying contrivances. These processes affect gene transcription, DNA replication and DNA repair, comprehending epigenetics as a key factor in understanding Aging and developing new avenues for delaying Aging, clinical advancements in ameliorating aging-related diseases and rejuvenating health. In the present article, we have described and advocated the epigenetic role in Aging and associated diseases.

Synthetic receptors in medicine.

Cellular signaling is controlled by ligand receptor interaction and subsequent biochemical changes inside the cell. Manipulating receptors as per need that can be a strategy to alter the disease pathologies in various conditions. With recent advances in synthetic biology, now it is possible to engineer the artificial receptor "synthetic receptors." Synthetic receptors are the engineering receptors that have potential to alter the disease pathology by altering/manipulating the cellular signaling. Several synthetic receptors are being engineered that have shown positive regulation in several disease conditions. Thus, synthetic receptor-based strategy opens a new avenue in the medical field to cope up with various health issues. The current chapter summarizes updated information about the synthetic receptors and their applications in the medical field.

Biomimetic Extracellular Matrix Nanofibers Electrospun with Calreticulin Promote Synergistic Activity for Tissue Regeneration.

In recognition of the potential of calreticulin (CRT) protein in enhancing the rate and quality of wound healing in excisional animal wound models, this study was to incorporate CRT via polyblend electrospinning into polycaprolactone (PCL)/type 1 collagen (Col1) nanofibers (NFs; 334 ± 75 nm diameter) as biomimetic extracellular matrices to provide a novel mode of delivery and protection of CRT with enhanced synergistic activities for tissue regeneration. Release kinetic studies using fluoresceinated CRT (CRT-FITC) polyblend NFs showed a burst release within 4 h reaching a plateau at 72 h, with further intervals of release upon incubation with fresh phosphate buffered saline for up to 8 weeks. By measuring fluorescence during the first 4 h of release, CRT-FITC-containing NFs were shown to protect CRT from proteolytic digestion (e.g., by subtilisin) compared to CRT-FITC in solution. CRT incorporated into NFs (CRT-NFs) also showed retention of biological activities and potency for stimulating proliferation and migration of human keratinocytes and fibroblasts. Fibroblasts seeded on CRT-NFs, after 2 days, showed increased amounts of fibronectin, TGF-ß1, and integrin ß1 in cell lysates by immunoblotting. Compared to NFs without CRT, CRT-NFs supported cell responses consistent with greater cell polarization and increased laminin-5 deposition of keratinocytes and a more motile phenotype of fibroblasts, as suggested by vinculin-capping F-actin fibers nonuniformly located throughout the cell body and the secretion of phosphorylated focal adhesion kinase-enriched migrasomes. Altogether, CRT electrospun into PCL/Col1 NFs retained its structural integrity and biological functions while having additional benefits of customizable loading, protection of CRT from proteolytic degradation, and sustained release of CRT from NFs, coupled with innate physicochemical cues of biomimetic PCL/Col1 NFs. Such synergistic activities have potential for healing recalcitrant wounds such as diabetic foot ulcers.

Effect of the vertical facial canal to round window distance concerning neural response telemetry during cochlear implantation in children.

OBJECTIVE: To assess the correlation of the distance from the round window (RW) to the vertical facial canal (VFC) with neural response telemetry thresholds (T-NRT), which may have an influence on the insertion trajectory and aid in preoperative surgical planning and electrode selection. METHODS: An observational study was conducted on 30 prelingually deaf children under five years diagnosed with bilateral severe to profound hearing loss and received a cochlear implant. The preoperative high resolution computed tomography (HRCT) images in the axial cut bone window setting at the round window level was used to calculate the distance from the RW to the VFC on the RadiAnt DICOM Viewer. The intraoperative distance was measured with ScopyDoc version 8.2.4 software. In Auto-NRT mode, software-based recordings (Cochlear's Custom Sound EP 6.0) were used to measure and evaluate the T-NRT current level. RESULTS: A statistically significant positive correlation of the RW to VFC distance with the average T-NRT p = 0.02, r = -0.4 and with the mid-frequency, T-NRT p = 0.003, r = -0.5 was found. CONCLUSION: The insertion trajectory can be ascertained by a statistically significant correlation between average T-NRT and mid-frequency T-NRT with RW and VFC distance, and this reliable factor can be taken into account in future surgical technique modulation, electrode selection, and electrode design.

Outcomes of Transcutaneous Retrobulbar Amphotericin B in Rhino-Orbital-Cerebral Mucormycosis Among Patients Recovering From COVID-19: A Preliminary Experience.

Background In this study, we aimed to assess the outcomes of transcutaneous retrobulbar injection of amphotericin B (TRAMB) in rhino-orbital-cerebral mucormycosis (ROCM) among patients recovering from coronavirus disease 2019 (COVID-19). Methodology This retrospective study was conducted at a tertiary care center in eastern India from May 29th to July 31st, 2021, and included post-COVID-19 patients admitted with stage 3 and 4a ROCM who underwent TRAMB. The details of the ophthalmic examination, laboratory investigations, and radiological examination were retrieved from patients records. Patients were given TRAMB (3.5 mg/mL) on alternate days till they underwent debulking surgery and resumed from the second postoperative day alternatively till the patients showed clinical stabilization or improvement. Results In total, 45 eyes of 41 patients were included in the study. The median number of injections given was six (minimum = 3; maximum = 10). Following was the distribution of number of injection needed in each eye: eight eyes (three injections), six eyes (four injections), seven eyes (five injections), three eyes (six injections), eight eyes (seven injections), 11 eyes (eight injections), and one eye had received nine and ten injections each. Overall, 21/32 (65.62%) eyes had improvement in proptosis whereas 9/32 (28.12%) had improvement in ptosis. Six patients had improvement in extraocular movement. In total, 25 eyes had no improvement whereas seven eyes had improvement in vision. Four eyes underwent exenteration. All nine patients with limited orbital disease had good improvement with fewer injections (median = 4). None of the patients undergoing TRAMB had an intracranial extension of disease. Moreover, 8.88% (4/45) of the eyes had post-TRAMB transient inflammation which resolved without any intervention. Finally, 3/41 of the patients died. Conclusions TRAMB can be considered as an useful therapeutic adjunct in managing ROCM. Further, it can halt the progression of the disease while awaiting definitive surgical intervention.

Hydrogel-mediated topical delivery of steroids can effectively alleviate psoriasis via attenuating the autoimmune responses.

Psoriasis is a systemic, relapsing, and chronic autoimmune inflammatory disease of the skin. Topical use of betamethasone, a glucocorticoid, in the form of creams is a common treatment for psoriasis. However, topical use of these creams is challenging due to the ineffective entrapment of steroids, burst release of the entrapped drugs, poor skin permeability, and high toxicity. Herein, we present the engineering of a betamethasone-loaded topical hydrogel (B-Gel) that can efficiently entrap steroids with high spreadability, and can also maintain the sustained release of drugs. We used an imiquimod (IMQ) induced ear psoriasis model, and demonstrated that topical application of B-Gel can mitigate the autoimmune inflammation reactions, and leads to a reduction in erythema, induration, scaling, and ear thickness. As interleukin 17 (IL-17) secreting T helper 17 (Th17) cells and γδ+ T cells are responsible for psoriasis, B-Gel treatment witnessed a reduction in the infiltration of leukocytes, CD4+ T cells, Th17 T cells, and dermal γδ+ T cells. We further demonstrated that B-Gel mediated reduction of IL-1ß, IL-17, and K16 (marker for keratinocyte proliferation) is responsible for alleviation of psoriasis. Therefore, the non-greasy nature of the hydrogel with a cooling effect provides an alternative for topical application of steroids.

Nonimmunogenic Hydrogel-Mediated Delivery of Antibiotics Outperforms Clinically Used Formulations in Mitigating Wound Infections.

Treatment of chronic wound infections caused by Gram-positive bacteria such as Staphylococcus aureus is highly challenging due to the low efficacy of existing formulations, thereby leading to drug resistance. Herein, we present the synthesis of a nonimmunogenic cholic acid-glycine-glycine conjugate (A6) that self-assembles into a supramolecular viscoelastic hydrogel (A6 gel) suitable for topical applications. The A6 hydrogel can entrap different antibiotics with high efficacy without compromising its viscoelastic behavior. Activities against different bacterial species using a disc diffusion assay demonstrated the antimicrobial effect of the ciprofloxacin-loaded A6 hydrogel (CPF-Gel). Immune profiling and gene expression studies after the application of the A6 gel to mice confirmed its nonimmunogenic nature to host tissues. We further demonstrated that topical application of CPF-Gel clears S. aureus-mediated wound infections more effectively than clinically used formulations. Therefore, cholic acid-derived hydrogels are an efficacious matrix for topical delivery of antibiotics and should be explored further.

Functions of, and replenishment strategies for, chondroitin sulfate in the human body.

Chondroitin sulfate (CS) belongs to a class of molecules called glycosaminoglycans (GAGs). These are long, linear chains of polysaccharides comprising alternating amino sugars and hexuronic acid. Similar to other GAGs, CS is important in a multitude of biological activities. Alteration of CS levels has been implicated in several pathological conditions, including osteoarthritis (OA) and other inflammatory diseases, as well as physiological conditions, such as aging. Therefore, devising replenishment strategies for this molecule is an important area of research. In this review, we discuss the nature of CS, its function in different organs, and its implications in health and disease. We also describe different methods for the exogenous administration of CS.

Breast tumor-on-chip models: From disease modeling to personalized drug screening.

Breast cancer is one of the leading causes of mortality worldwide being the most common cancer among women. Despite the significant progress obtained during the past years in the understanding of breast cancer pathophysiology, women continue to die from it. Novel tools and technologies are needed to develop better diagnostic and therapeutic approaches, and to better understand the molecular and cellular players involved in the progression of this disease. Typical methods employed by the pharmaceutical industry and laboratories to investigate breast cancer etiology and evaluate the efficiency of new therapeutic compounds are still based on traditional tissue culture flasks and animal models, which have certain limitations. Recently, tumor-on-chip technology emerged as a new generation of in vitro disease model to investigate the physiopathology of tumors and predict the efficiency of drugs in a native-like microenvironment. These microfluidic systems reproduce the functional units and composition of human organs and tissues, and importantly, the rheological properties of the native scenario, enabling precise control over fluid flow or local gradients. Herein, we review the most recent works related to breast tumor-on-chip for disease modeling and drug screening applications. Finally, we critically discuss the future applications of this emerging technology in breast cancer therapeutics and drug development.

Topical Application of Peptide-Chondroitin Sulfate Nanoparticles Allows Efficient Photoprotection in Skin.

In this article, we describe a method of delivery of chondroitin sulfate to skin as nanoparticles and demonstrate its anti-inflammatory and antioxidant role using UV irradiation as a model condition. These nanoparticles, formed through electrostatic interactions of chondroitin sulfate with a skin-penetrating peptide, were found to be homogenous with positive surface charges and stable at physiological and acidic pH under certain conditions. They were able to enter into the human keratinocyte cell line (HaCaT), artificial skin membrane (mimicking the human skin), and mouse skin tissue unlike free chondroitin sulfate. The preapplication of nanoparticles also exhibited reduced levels of oxidative stress, cyclobutane pyrimidine dimer formation, TNF-α, and so on in UV-B-irradiated HaCaT cells. In an acute UV-B irradiation mouse model, their topical application resulted in reduced epidermal thickness and sunburn cells, unlike in the case of free chondroitin sulfate. Thus, a completely noninvasive method was used to deliver a bio-macromolecule into the skin without using injections or abrasive procedures.

Role of Cellular Retention and Intracellular State in Controlling Gene Delivery Efficiency of Multiple Nonviral Carriers.

Nonviral gene delivery has seen major progress in the last two decades owing to facile synthesis, low toxicity, and ease of modification of nanocarriers that take nucleic acids to cells and tissues. Gene delivery nanocomplexes need to reach the target locations in significant amounts by overcoming multiple barriers. While the importance of nanocomplex stability, cellular uptake, intracellular trafficking, and nuclear localization has been studied extensively, the role of cellular retention and recycling of these nanocomplexes is less understood in the context of gene delivery. In this study, we used different DNA carriers and made efforts to understand the role played by cellular retention in determining their gene delivery efficiency across multiple cell lines. In addition, we also analyzed whether state of complexation and localization of the nanocomplexes play a role in conjunction with cellular retention. We observed higher transfection efficiencies for nanocomplexes showing better retention, lower unpackaging, and low recycling. Our data also suggests that nanocomplexes made of peptides with terminal cysteine modification show enhanced retention and transfection efficiency compared to their counterparts with no terminal cysteine. Overall, the work highlights myriad of factors to be considered for improving gene delivery efficiency of nanocomplexes.

Evaluation of Association of Allergic Rhinitis with Bronchial Asthma.

Allergic rhinitis represents a global health problem. It is a common disease worldwide affecting about 10-50 % of the population and its prevalence is increasing. Although allergic rhinitis is not a fatal disease, it alters the social life of patients, affecting learning performance and work productivity. Moreover, the costs incurred by allergic rhinitis are substantial. In recent years allergic rhinitis has been recognized to be an important risk factor for asthma. The concept of "One Airway, One Disease" was highlighted in the 'Allergic rhinitis and its Impact on Asthma 'guidelines and has arisen as a result of the now well-established link between the upper and lower airways. The aim of this study was to evaluate the association between allergic rhinitis and bronchial asthma by determining the incidence of bronchial asthma in patients of allergic rhinitis and the incidence of allergic rhinitis in patients of bronchial asthma. 83 diagnosed cases each of allergic rhinitis and bronchial asthma were recruited from patients attending Otorhinolaryngology and pulmonary department of the institute. All patients were subjected to detail ENT and pulmonary examination and investigated for nasal and bronchial allergy. In the allergic group, which consisted of 83 diagnosed patients of allergic rhinitis, 49 (59.03 %) were diagnosed to have bronchial asthma, whereas in the bronchial asthma group, which consisted of 83 diagnosed patients of bronchial asthma 61 (78.20 %) were diagnosed to have comorbid allergic rhinitis. It was observed that patients with allergic rhinitis were likely to develop bronchial asthma, and patients of allergic rhinitis should be evaluated for bronchial asthma, for early detection and treatment of the co morbid condition.

Silymarin-loaded nanostructured lipid carrier gel for the treatment of skin cancer.

Aim: The present study was aimed at determining the antiproliferative, antioxidant, anti-inflammatory and antitumor activity of developed silymarin-nanostructured lipid carrier (NLC) gel. Materials & methods: B16 melanoma cell line and albino mice were used as ex vivo and in vivo models, respectively, to evaluate the aforementioned pharmacological activities. Results: The volume of large tumors significantly (p < 0.05) reduced from 5.02 to 3.05 mm3, levels of IL-1α and TNF-α were significantly (p < 0.001) lower and levels of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) significantly (p < 0.0001) increased in the group treated with silymarin-NLC gel. Furthermore, in skin treated with placebo and conventional gels, a basosquamous carcinoma and squamous cell carcinoma were noticed, respectively. Conclusion: Silymarin-NLC gel presented better treatment outcomes compared with silymarin-conventional gel.

Deciphering the Role of Chondroitin Sulfate in Increasing the Transfection Efficiency of Amphipathic Peptide-Based Nanocomplexes.

Glycosaminoglycans, both cell-surface and exogenous, can interfere with DNA delivery efficiency of nonviral carrier systems. In this work, we report an extensive comparative study to explore the effect of exogenously added chondroitin sulfate on biophysical characteristics, cellular uptake, transfection efficiency, and intracellular trafficking of nanocomplexes formed using primary and secondary amphipathic peptides developed in our laboratory. Our results indicate that the presence of exogenous chondroitin sulfate exhibits differential enhancement in transfection efficiency of the amphipathic peptides depending upon their chemical nature. The enhancement was more pronounced in primary amphipathic peptide-based nanocomplexes as compared to the secondary counterpart. This difference can be attributed to possible alteration of the intracellular entry pathway in addition to increased extracellular stability, less cellular toxicity, and assistance in nuclear accumulation. These results imply potential use of glycosaminoglycans such as chondroitin sulfate to improve the transfection efficiency of primary amphipathic peptides for possible in vivo applications.

Effects on auditory function of chronic exposure to electromagnetic fields from mobile phones.

The widespread use of mobile phones has given rise to apprehension regarding the possible hazardous health effects of high-frequency electromagnetic fields (EMFs) on auditory function. We conducted a study to investigate the effects of long-term (>4 yr) exposure to EMFs emitted by mobile phones on auditory function. Our study population was made up of 40 healthy medical students-31 men and 9 women, aged 20 to 30 years (mean 22.7). Of this group, 31 subjects typically held their phone to the right ear and 9 to the left ear; the non-phone-using ear served as each subject's control ear. The phone-using subjects were also split into two groups of 20 based on the duration of their daily phone use (≤60 min vs. >60 min). All subjects underwent pure-tone audiometry, speech audiometry, impedance audiometry, and brainstem evoked response audiometry (BERA), and comparisons were made between the phone-using ear and the control ear and between the shorter and longer duration of daily use. We found no statistically significant differences in high-frequency pure-tone average between the phone-using ears and the control ears (p = 0.69) or between the shorter- and longer-duration phone-using ears (p = 0.85). Moreover, statistical analysis of BERA findings revealed no significant differences between the phone-using ears and the control ears in terms of wave I-III, III-V, and I-V interpeak latencies (p = 0.59, 0.74 and 0.44, respectively). None of the subjects reported any subjective symptoms, such as headache, tinnitus, or sensations of burning or warmth behind, around, or on the phone-using ear. We conclude that the long-term exposure to EMFs from mobile phones does not affect auditory function.

Endoscopic Repair of CSF Rhinorrhea: An Institutional Experience.

INTRODUCTION: Endoscopic repair is considered the treatment of choice in cerebrospinal fluid (CSF) rhinorrhea. The aim of our study was to analyze the etiopathogenesis of CSF rhinorrhea, the outcome of treatment and the causes of failure in a developing-country setting. MATERIALS AND METHODS: A retrospective review of patients treated with endoscopic repair for CSF rhinorrhea at a tertiary care hospital in southern India from January 2002 to December 2009 identified 36 patients, the majority of them being women. The defects were closed in three layers using fat, fascia lata and nasal mucosa along with a fibrin sealant in the majority of the patients. Per-operatively, a subarachnoid drain was placed in all patients. Patients were followed up for 1 year. RESULTS: Spontaneous onset of CSF rhinorrhea was noted in 61% of patients. The most common site of leak was found to be the left cribriform plate area. Hence the most common cause of CSF rhinorrhea in our study was spontaneous and the second most common was post-traumatic. Our success rate on the first attempt at endoscopic repair was 100%, with a recurrence rate of 6%. A large defect, failure of localization of the defect, or other co-morbid conditions such as chronic cough may be the most likely causes of recurrence of leak. CONCLUSION: Accurate localization of the site of lesion using a high-resolution computed tomography (CT) scan with magnetic resonance imaging (MRI) and confirmation of the site of leak by intraoperative Valsalva maneuver along with multilayered closure of the dural defect and post-operative lumbar drain appear to be essential for the successful endoscopic repair of CSF rhinorrhea.

Waldenstrom macroglobulinemia presenting as isolated persistent epistaxis: a very rare presentation.

Nose bleed is the most common rhinological emergency. There are multiple risk factors for the development of epistaxis and it can affect any age group, but it is the elderly population with their associated morbidity who often require more intensive treatment and subsequent admission. Most cases of epistaxis occur in the Little's area, a location readily accessible and treatable by cautery or anterior nasal packing. However, posterior epistaxis often requires more aggressive measures including posterior nasal packing and endoscopic cauterization. After posterior nasal packing, the two most common therapies for intractable epistaxis are transantral ligation of the internal maxillary artery and percutaneous embolization of the distal internal maxillary artery. However, optimal management of intractable posterior epistaxis remains controversial. We hereby report fourth case of Waldenstrom Macroglobulinemia in English literature, which presented as isolated persistent epistaxis and was treated by therapeutic plasmapheresis.