Distinct effects of cardiac mitochondrial calcium uniporter inactivation via EMRE deletion in the short and long term.

Transport of Ca2+ into mitochondria is thought to stimulate the production of ATP, a critical process in the heart's fight or flight response, but excess Ca2+ can trigger cell death. The mitochondrial Ca2+ uniporter complex is the primary route of Ca2+ transport into mitochondria, in which the channel-forming protein MCU and the regulatory protein EMRE are essential for activity. In previous studies, chronic Mcu or Emre deletion differed from acute cardiac Mcu deletion in response to adrenergic stimulation and ischemia/reperfusion (I/R) injury, despite equivalent inactivation of rapid mitochondrial Ca2+ uptake. To explore this discrepancy between chronic and acute loss of uniporter activity, we compared short-term and long-term Emre deletion using a novel conditional cardiac-specific, tamoxifen-inducible mouse model. After short-term Emre deletion (3 weeks post-tamoxifen) in adult mice, cardiac mitochondria were unable to take up Ca2+, had lower basal mitochondrial Ca2+ levels, and displayed attenuated Ca2+-induced ATP production and mPTP opening. Moreover, short-term EMRE loss blunted cardiac response to adrenergic stimulation and improved maintenance of cardiac function in an ex vivo I/R model. We then tested whether the long-term absence of EMRE (3 months post-tamoxifen) in adulthood would lead to distinct outcomes. After long-term Emre deletion, mitochondrial Ca2+ handling and function, as well as cardiac response to adrenergic stimulation, were similarly impaired as in short-term deletion. Interestingly, however, protection from I/R injury was lost in the long-term. These data suggest that several months without uniporter function are insufficient to restore bioenergetic response but are sufficient to restore susceptibility to I/R.

Biosafety in DIY-bio laboratories: from hype to policy: Discussions about regulating DIY biology tend to ignore the extent of self-regulation and oversight of DIY laboratories.

Policymakers should treat DIY-biology laboratories as legitimate parts of the scientific enterprise and pay attention to the role of community norms.

Dementia Detection from Speech Using Machine Learning and Deep Learning Architectures.

Dementia affects the patient's memory and leads to language impairment. Research has demonstrated that speech and language deterioration is often a clear indication of dementia and plays a crucial role in the recognition process. Even though earlier studies have used speech features to recognize subjects suffering from dementia, they are often used along with other linguistic features obtained from transcriptions. This study explores significant standalone speech features to recognize dementia. The primary contribution of this work is to identify a compact set of speech features that aid in the dementia recognition process. The secondary contribution is to leverage machine learning (ML) and deep learning (DL) models for the recognition task. Speech samples from the Pitt corpus in Dementia Bank are utilized for the present study. The critical speech feature set of prosodic, voice quality and cepstral features has been proposed for the task. The experimental results demonstrate the superiority of machine learning (87.6 percent) over deep learning (85 percent) models for recognizing Dementia using the compact speech feature combination, along with lower time and memory consumption. The results obtained using the proposed approach are promising compared with the existing works on dementia recognition using speech.

Geographical distribution of primary & secondary dengue cases in India - 2017: A cross-sectional multicentric study.

Background & objectives: Dengue virus infection is endemic in India with all the four serotypes of dengue virus in circulation. This study was aimed to determine the geographic distribution of the primary and secondary dengue cases in India. Methods: A multicentre cross-sectional study was conducted at Department of Health Research / Indian Council of Medical Research (DHR)/(ICMR) viral research and diagnostic laboratories (VRDLs) and selected ICMR institutes located in India. Only laboratory-confirmed dengue cases with date of onset of illness less than or equal to seven days were included between September and October 2017. Dengue NS1 antigen ELISA and anti-dengue IgM capture ELISA were used to diagnose dengue cases while anti-dengue IgG capture ELISA was used for identifying the secondary dengue cases. Results: Of the 1372 dengue cases, 897 (65%) were classified as primary dengue and 475 (35%) as secondary dengue cases. However, the proportion varied widely geographically, with Theni, Tamil Nadu; Tirupati, Andhra Pradesh and Udupi-Manipal, Karnataka reporting more than 65 per cent secondary dengue cases while Srinagar, Jammu and Kashmir reporting as low as 10 per cent of the same. The median age of primary dengue cases was 25 yr [interquartile range (IQR 17-35] while that of secondary dengue cases was 23 yr (IQR 13.5-34). Secondary dengue was around 50 per cent among the children belonging to the age group 6-10 yr while it ranged between 20-43 per cent among other age groups. Interpretation & conclusions: Our findings showed a wide geographical variation in the distribution of primary and secondary dengue cases in India. It would prove beneficial to include primary and secondary dengue differentiation protocol in the national dengue surveillance programme.

The Management of an Unusual Combination of Anomalies Following Primary Tooth Trauma: A Case Report.

The prognosis of luxation injuries of primary teeth is often unpredictable. A two-year-old girl presented with a displaced left primary maxillary anterior tooth diagnosed as severe intrusive luxation. On radiographic examination, it was noticed to be impinging on the underlying permanent tooth bud. The tooth was extracted, and periodic follow-ups were emphasized until the successor tooth erupted. However, after eight years, the patient followed up with a chief complaint of an unerupted permanent maxillary anterior tooth. Cone-beam computed tomography (CBCT) revealed a combination of anomalies in the crown and root of the maxillary anterior tooth. After a wait-and-observe regime for six months, the incisal third of the crown erupted. At eight years and eight months, the tooth developed a periapical abscess which was treated endodontically and restored. At nine years and three months, the tooth is asymptomatic till date. The present case report highlights the consequences of intrusive luxation injuries to the primary teeth and the need for a multidisciplinary team approach in the management of complications of dental trauma along with meticulous long-term follow-ups.

Comparison of two different caries risk assessment tools for infants and toddlers - A cross-sectional study.

CONTEXT: One of the essential components for successful caries management is caries risk assessment (CRA). Among CRA tools (CRATs) published in the literature: Caries management by risk assessment (CAMBRA) 123 and American Academy of Pediatric Dentistry (AAPD) CRATs are specifically designed for infants and toddlers. AIMS: The aim of this study is to compare readily available internationally accepted CRAT for infants and toddlers and check the usability of these tools in assigning caries risk among the Indian population. SETTINGS AND DESIGN: The study was conducted at Baby Oral Health Promotion Clinic, Department of Pediatrics, Tertiary Care Hospital using a cross-sectional study design. SUBJECTS AND METHODS: Data were collected using CAMBRA 123 and AAPD CRATs from 379 children aged 0-6 years. The caries risk of the children was recorded with each CRAT and a comparison was made between the two tools used. STATISTICAL ANALYSIS USED: The percentage of agreement and Cohen's kappa coefficient were used to know the agreement between the CAMBRA 123 and AAPD CRATs using the SPSS statistical tool. The significance level was set at 5% (α = 0.05). RESULTS: For children aged <2 years, the study showed slight agreement between the CAMBRA 123 and AAPD, whereas, for children more than 2 years, there was a fair agreement between the two methods which was statistically significant. This indicates that the agreement between the two methods is still not perfectly established, and AAPD CRA assigns a higher risk category than CAMBRA 123. CONCLUSIONS: CAMBRA 123 is a promising user-friendly quantitative method for CRA in clinical practice. Since there is ambiguity in assessing the caries risk in children <2 years, there is a need to establish a CRAT that can be used exclusively for children below 2 years.

Sagittal balance in sitting and standing positions: A systematic review of radiographic measures.

Background: Sagittal imbalance can be caused by various etiologies and is among the most important indicators of spinal deformity. Sagittal balance can be restored through surgical intervention based on several radiographic measures. The purpose of this study is to review the normal parameters in the sitting position, which are not well understood and could have significant implications for non-ambulatory patients. Methods: A systematic review was performed adhering to PRISMA Guidelines. Using R-software, the weighted means and 95% confidence intervals of the radiographic findings were calculated using a random effect model and significance testing using unpaired t-tests. Results: 10 articles with a total of 1066 subjects reported radiographic measures of subjects with no spinal deformity in the sitting and standing position. In the healthy individual, standing sagittal vertical axis -16.8°was significantly less than sitting 28.4° (p < 0.0001), while standing lumbar lordosis 43.3°is significantly greater than sitting 21.3° (p < 0.0001). Thoracic kyphosis was not significantly different between the two groups (p = 0.368). Standing sacral slope 34.3° was significantly greater than sitting 19.5° (p < 0.0001) and standing pelvic tilt 14.0° was significantly less than sitting 33.9° (p < 0.0001). Conclusions: There are key differences between standing and sitting postures, which could lead to undue stress on surgical implants and poor outcomes, especially for non-ambulatory populations. There is a need for more studies reporting sitting and standing radiographic measures in different postures and spinal conditions.

Synthetic biology regulation in Europe: containment, release and beyond.

While synthetic biology is hoped to hold promise and potential to address pressing global challenges, the issue of regulation is an under-appreciated challenge. Particularly in Europe, the regulatory frameworks involved are rooted in historical concepts based on containment and release. Through a series of case studies including a field-use biosensor intended to detect arsenic in well water in Nepal and Bangladesh, and insects engineered for sterility, we explore the implications that this regulatory and conceptual divide has had on the deployment of synthetic biology projects in different national contexts. We then consider some of the broader impacts that regulation can have on the development of synthetic biology as a field, not only in Europe but also globally, with a particular emphasis on low- and middle-income countries. We propose that future regulatory adaptability would be increased by moving away from a containment and release dichotomy and toward a more comprehensive assessment that accounts for the possibility of varying degrees of 'contained release'. Graphical Abstract.

Frequency settings of subthalamic nucleus DBS for Parkinson's disease: A systematic review and network meta-analysis.

INTRODUCTION: Deep Brain Stimulation (DBS) is an effective treatment for the motor symptoms of Parkinson's Disease. The targeted physiological structure for lead location is commonly the subthalamic nucleus (STN). The efficacy of DBS for improving motor symptoms is assessed via the Unified Parkinson's Disease Rating III Scale (UPDRS-III). In this study, we sought to compare the efficacy of frequency settings utilized for STN-DBS. METHODS: Following PRISMA Guidelines, a search on PUBMED and MEDLINE was performed to include full-length randomized controlled trials evaluating STN-DBS. The frequency stimulation parameters and Unified Parkinson's Disease Rating Scale (UPDRS-III) outcomes were extracted in the search. High-frequency stimulation (HFS) was defined as ≥100 Hz and low-frequency stimulation (LFS) was defined as <100 Hz. A frequentist network meta-analysis was performed with odds ratios (OR) and pooling performed using the Mantel-Haenszel method. Statistics are presented as OR [95% CI]. RESULTS: 15 studies consisting of 298 patients were included for analysis. Bilateral HFS -0.68 [-0.89; -0.46] was associated with better UPDRS-III scores compared to bilateral LFS. On the other hand, bilateral LFS with medications (MEDS) was favored over HFS with MEDS (-0.28 [-0.63; 0.07]). Bilateral LFS and MEDS, HFS and MEDS, stimulation (STIM) OFF MEDS ON, HFS, LFS, STIM OFF MEDS OFF UPDRS outcomes were ranked from best to worst outcomes. DISCUSSION: The outcomes of this study suggest that bilateral HFS has better utility for those with no response to medication, while LFS has additive benefits to medication by improving unique symptoms via different neurophysiological mechanisms.

WITHDRAWN: Laterality and frequency settings of subthalamic nucleus DBS for Parkinson's disease: A systematic review and network meta-analysis.

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/policies/article-withdrawal.

Glanzmann thrombasthenia: Use of hemocoagulase (BotroClot) for arrest of bleeding during a primary tooth endodontic procedure.

The Rationale: Glanzmann thrombasthenia is a rare platelet disorder affecting 0.0001% of the population. Dentists may often be unaware of this condition, and manipulation of soft tissue can lead to grave consequences, which may even result in fatality. Patient Concerns: In this case report, a 4-year-old patient with Glanzmann thrombasthenia reported to the department with a chief complaint of a discoloured tooth. Clinical Findings: On examination, 51 was nonvital, and pulpectomy was the treatment planned. The non-vital anterior tooth was treated with a pulpectomy procedure. There was uncontrolled bleeding during the procedure. Treatment: A topical solution of BotroClot was used to arrest the bleeding, and obturation was completed following that. The post-operative period was uneventful. Take-away Lessons: Case report explored the use of a topical hemostatic agent to arrest bleeding from the canal. This case report warrants eliciting a thorough medical history before any dental procedure.

Orthovoltage X-Rays Exhibit Increased Efficacy Compared with γ-Rays in Preclinical Irradiation.

Radionuclide irradiators (137Cs and 60Co) are commonly used in preclinical studies ranging from cancer therapy to stem cell biology. Amidst concerns of radiological terrorism, there are institutional initiatives to replace radionuclide sources with lower energy X-ray sources. As researchers transition, questions remain regarding whether the biological effects of γ-rays may be recapitulated with orthovoltage X-rays because different energies may induce divergent biological effects. We therefore sought to compare the effects of orthovoltage X-rays with 1-mm Cu or Thoraeus filtration and 137Cs γ-rays using mouse models of acute radiation syndrome. Following whole-body irradiation, 30-day overall survival was assessed, and the lethal dose to provoke 50% mortality within 30-days (LD50) was calculated by logistic regression. LD50 doses were 6.7 Gy, 7.4 Gy, and 8.1 Gy with 1-mm Cu-filtered X-rays, Thoraeus-filtered X-rays, and 137Cs γ-rays, respectively. Comparison of bone marrow, spleen, and intestinal tissue from mice irradiated with equivalent doses indicated that injury was most severe with 1-mm Cu-filtered X-rays, which resulted in the greatest reduction in bone marrow cellularity, hematopoietic stem and progenitor populations, intestinal crypts, and OLFM4+ intestinal stem cells. Thoraeus-filtered X-rays provoked an intermediate phenotype, with 137Cs showing the least damage. This study reveals a dichotomy between physical dose and biological effect as researchers transition to orthovoltage X-rays. With decreasing energy, there is increasing hematopoietic and intestinal injury, necessitating dose reduction to achieve comparable biological effects. SIGNIFICANCE: Understanding the significance of physical dose delivered using energetically different methods of radiation treatment will aid the transition from radionuclide γ-irradiators to orthovoltage X-irradiators.

Double-masked, sham and placebo-controlled trial of corneal cross-linking and topical difluprednate in the treatment of bacterial keratitis: Steroids and Cross-linking for Ulcer Treatment Trial (SCUT II) study protocol.

INTRODUCTION: Although antibiotics are successful at achieving microbiological cure in infectious keratitis, outcomes are often poor due to corneal scarring. Ideal treatment of corneal ulcers would address both the infection and the inflammation. Adjunctive topical steroid treatment may improve outcomes by reducing inflammation. Corneal cross-linking (CXL) is a novel prospective therapy that may simultaneously reduce both inflammatory cells and bacterial pathogens. The purpose of this study is to determine differences in 6-month visual acuity between standard medical therapy with antibiotics versus antibiotics with adjunctive early topical steroid therapy versus antibiotic treatment plus CXL and early topical steroids. METHODS AND ANALYSIS: This international, randomised, sham and placebo-controlled, three-arm clinical trial randomises patients with smear positive bacterial ulcers in a 1:1:1 fashion to one of three treatment arms: (1) topical 0.5% moxifloxacin plus topical placebo plus sham CXL; (2) topical 0.5% moxifloxacin plus difluprednate 0.05% plus sham CXL; or (3) the CXL group: topical 0.5% moxifloxacin plus difluprednate 0.05% plus CXL. ETHICS AND DISSEMINATION: We anticipate that both adjunctive topical steroids and CXL will improved best spectacle corrected visual acuity and also reduce complications such as corneal perforation and the need for therapeutic penetrating keratoplasty. This study will comply with the NIH Data Sharing Policy and Policy on the Dissemination of NIH-Funded Clinical Trial Information and the Clinical Trials Registration and Results Information Submission rule. Our results will be disseminated via ClinicalTrials.gov website, meetings and journal publications. Our data will also be available on reasonable request. TRIAL REGISTRATION NUMBER: NCT04097730.

A solution scan of societal options to reduce transmission and spread of respiratory viruses: SARS-CoV-2 as a case study.

Societal biosecurity - measures built into everyday society to minimize risks from pests and diseases - is an important aspect of managing epidemics and pandemics. We aimed to identify societal options for reducing the transmission and spread of respiratory viruses. We used SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) as a case study to meet the immediate need to manage the COVID-19 pandemic and eventually transition to more normal societal conditions, and to catalog options for managing similar pandemics in the future. We used a 'solution scanning' approach. We read the literature; consulted psychology, public health, medical, and solution scanning experts; crowd-sourced options using social media; and collated comments on a preprint. Here, we present a list of 519 possible measures to reduce SARS-CoV-2 transmission and spread. We provide a long list of options for policymakers and businesses to consider when designing biosecurity plans to combat SARS-CoV-2 and similar pathogens in the future. We also developed an online application to help with this process. We encourage testing of actions, documentation of outcomes, revisions to the current list, and the addition of further options.

80 questions for UK biological security.

Multiple national and international trends and drivers are radically changing what biological security means for the United Kingdom (UK). New technologies present novel opportunities and challenges, and globalisation has created new pathways and increased the speed, volume and routes by which organisms can spread. The UK Biological Security Strategy (2018) acknowledges the importance of research on biological security in the UK. Given the breadth of potential research, a targeted agenda identifying the questions most critical to effective and coordinated progress in different disciplines of biological security is required. We used expert elicitation to generate 80 policy-relevant research questions considered by participants to have the greatest impact on UK biological security. Drawing on a collaboratively-developed set of 450 questions, proposed by 41 experts from academia, industry and the UK government (consulting 168 additional experts) we subdivided the final 80 questions into six categories: bioengineering; communication and behaviour; disease threats (including pandemics); governance and policy; invasive alien species; and securing biological materials and securing against misuse. Initially, the questions were ranked through a voting process and then reduced and refined to 80 during a one-day workshop with 35 participants from a variety of disciplines. Consistently emerging themes included: the nature of current and potential biological security threats, the efficacy of existing management actions, and the most appropriate future options. The resulting questions offer a research agenda for biological security in the UK that can assist the targeting of research resources and inform the implementation of the UK Biological Security Strategy. These questions include research that could aid with the mitigation of Covid-19, and preparation for the next pandemic. We hope that our structured and rigorous approach to creating a biological security research agenda will be replicated in other countries and regions. The world, not just the UK, is in need of a thoughtful approach to directing biological security research to tackle the emerging issues.

Immediate effect of Kapalbhathi pranayama on short term heart rate variability (HRV) in healthy volunteers.

OBJECTIVES: Kapalbhathi Pranayam (Kapal = forehead; bhati = shining) is a breathing exercise that has been practiced to cleanse the frontal brain in traditional practices like yoga. Still, there exists a dearth of literature on the effect of Kapalbhathi pranayama on physiological systems. So this present study was carried out to find the immediate effect of "kapalbhathi Pranayam" practice for the period of 5 min on cardiac autonomic function among the healthy volunteers. MATERIALS AND METHODS: Apparently 50 healthy volunteers includes both sex were participated. They were randomly divided into Pranayama (n-25) and control (n-25) group. Pranayama group was practiced kapalbhathi pranayama 5 min (5 cycles) and control group was allowed to do normal breathing (12-16 breath/min). Lead II ECG was recorded for 5 min using simple AD converter before, immediately after practice and 20 min of recovery period. RESULTS: One way Analysis of variance (ANOVA) followed by post hoc test was done using R statistical software. There was a significant (p < 0.05) parasympathetic withdrawal (Root Mean Square of the Successive Differences (RMSSD) - p < 0.04 and HF n.u - p < 0.05) was found in the pranayama group immediately after practice and its was changed to parasympathetic domination (RMSSD - p < 0.04 and HF n.u - p < 0.05) after 20 min of recovery period. CONCLUSION: The present study suggested that though there was parasympathetic withdrawal immediately after practicing kapalbhathi pranayama, 20 min after the recovery period showed a parasympathetic domination in the pranayama group subjects. However, further studies are required to warrant the findings of this study.

Vitamin D deficiency as an etiological factor in delayed eruption of primary teeth: A cross-sectional study.

CONTEXT: Delayed tooth eruption might be the primary or sole manifestation of local or systemic pathology. Aims: The aim of the study was to correlate Vitamin D level and eruption status of primary teeth. The objectives also included the assessment of the association between Vitamin D levels and socioeconomic status, infant's sun exposure, maternal sun exposure during pregnancy and religion. SETTINGS AND DESIGN: A cross-sectional, observational study conducted on 96 infants aged 12-15 months. MATERIALS AND METHODS: Ninety-six infants, aged 12-15 months were selected after obtaining parental consent. Blood samples were assessed for Vitamin D3 levels using the Vitamin D ELISA Kit. The eruption status of the teeth was recorded in all the 96 infants. The obtained data were subjected to the statistical analysis. STATISTICAL ANALYSIS USED: The obtained data were subjected to relevant statistical analysis such as Analysis of Variance, unpaired t-test, Kruskal-Wallis test, and Mann-Whitney U test, Chi-square Test, Tukey HSD, and Fisher's exact Test. Results: A significant correlation was found in the Vitamin D levels and the eruption timing (P < 0.001). The difference in mean Vitamin D levels among the three socio economic groups was not statistically significant (P = 0.088). A significant association was found between the infant's sun exposure and mother's sun exposure during pregnancy and religion on the Vitamin D levels (P = 0.002, P = 0.042, P = 0.002). CONCLUSIONS: Vitamin D deficiency can be considered as an etiological factor for delayed eruption. A strong association exists between the socioeconomic status, infant's sun exposure, maternal sun exposure during pregnancy, and religion with Vitamin D levels.

Bioengineering horizon scan 2020.

Horizon scanning is intended to identify the opportunities and threats associated with technological, regulatory and social change. In 2017 some of the present authors conducted a horizon scan for bioengineering (Wintle et al., 2017). Here we report the results of a new horizon scan that is based on inputs from a larger and more international group of 38 participants. The final list of 20 issues includes topics spanning from the political (the regulation of genomic data, increased philanthropic funding and malicious uses of neurochemicals) to the environmental (crops for changing climates and agricultural gene drives). The early identification of such issues is relevant to researchers, policy-makers and the wider public.

Solid waste management of local governments in the Western Province of Sri Lanka: An implementation analysis.

The large-scale solid waste generation has been a critical issue in the world today. The absence of a sound national policy for Solid Waste Management (SWM) has caused tremendous negative environmental consequences in Sri Lanka. Despite various programs being implemented by the Municipal Councils and other local governments with the relevant authorities in managing solid waste, most of them have not been successful. Thus, the main purpose of this study is to examine major factors affecting successful policy implementation of the SWM. Further, the study identifies problems and challenges faced in the implementation of SWM. Both qualitative and quantitative methods were used to gather primary and secondary data. Interview and in-depth discussions were conducted with selected officers who are responsible for implementation of SWM system to identify problems and challenges at the implementation level. Among the 48 LGs in the Western Province, 50% (twenty-four) LGs were selected based on the stratified random sampling method for the quantitative analysis. Normally, in each LG, five officers are responsible for SWM. There are 10 officers in the Colombo Municipal Council who are responsible for SWM. Thus, the total population is 245. Thus, the sample is 125. The sample was consisting of Administrative Heads, Public Health Officer and related officers of each Local Government. A field survey was carried out with a structured questionnaire based on the literature review focusing on the variables of the study. The questionnaire was administered by a Research Assistant. The study found that the remuneration and other facilities of the staff, their commitment, the motivation and the support from the political leadership, the contribution of the society and the business community are significantly affecting the successful implementation of the SWM program. The SWM has not been successful at its implementation stage due to some administrative problems such as insufficient land for final dumping, composting and recycling, lack of necessary vehicles and an integrated SWM programme, lack of necessary instruments and modern technology, poor regulatory framework, lower labor productivity and quantity, lack of awareness of residents and inappropriate political interference. Finally, the study proposes policy recommendations for addressing those administrative problems and challenges towards efficient and effective solid waste management in the local governments in Sri Lanka.

Interaction of chitin/chitosan with salivary and other epithelial cells-An overview.

Chitin and its deacetylated form, chitosan, have been widely used for tissue engineering of both epithelial and mesenchymal tissues. Epithelial cells characterised by their sheet-like tight cellular arrangement and polarised nature, constitute a major component in various organs and play a variety of roles including protection, secretion and maintenance of tissue homeostasis. Regeneration of damaged epithelial tissues has been studied using biomaterials such as chitin, chitosan, hyaluronan, gelatin and alginate. Chitin and chitosan are known to promote proliferation of various embryonic and adult epithelial cells. However it is not clearly understood how this activity is achieved or what are the mechanisms involved in the chitin/chitosan driven proliferation of epithelial cells. Mechanistic understanding of influence of chitin/chitosan on epithelial cells will guide us to develop more targeted regenerative scaffold/hydrogel systems. Therefore, current review attempts to elicit a mechanistic insight into how chitin and chitosan interact with salivary, mammary, skin, nasal, lung, intestinal and bladder epithelial cells.