Lateral assembly of N-cadherin drives tissue integrity by stabilizing adherens junctions

Cadherin interactions ensure the correct registry and anchorage of cells during tissue formation. Along the plasma membrane, cadherins form inter-junctional lattices via cis- and trans-dimerization. While structural studies have provided models for cadherin interactions, the molecular nature of cadherin binding in vivo remains unexplored. We undertook a multi-disciplinary approach combining live cell imaging of three-dimensional cell assemblies (spheroids) with a computational model to study the dynamics of N-cadherin interactions. Using a loss-of-function strategy, we demonstrate that each N-cadherin interface plays a distinct role in spheroid formation. We found that cis-dimerization is not a prerequisite for trans-interactions, but rather modulates trans-interfaces to ensure tissue stability. Using a model of N-cadherin junction dynamics, we show that the absence of cis-interactions results in low junction stability and loss of tissue integrity. By quantifying the binding and unbinding dynamics of the N-cadherin binding interfaces, we determined that mutating either interface results in a 10-fold increase in the dissociation constant. These findings provide new quantitative information on the steps driving cadherin intercellular adhesion and demonstrate the role of cis-interactions in junction stability.

Correlation of Radiographic Mental Foramen Position and Occulusion in Three Different Indian Populations

BACKGROUND

The knowledge of the position of the mental foramen (MF) is important for administering local anaesthesia for diagnostic, surgical or operative procedures.

AIMS

To determine the shape, position, symmetry of MF and its continuity with the inferior dental canal (IDC) on a digital panoramic view and to find its correlation with Angle's molar relations in three Indian subpopulations. The study also determines the correlation of inter-foramen distance in both genders of three Indian subpopulations.

SUBJECTS AND METHODS

One hundred and twenty digital panoramic radiographs were evaluated from three Indian subpopulations (Punjab, Rajasthan and Northeast [NE]). The assessment of occlusion was based on Angle's molar relationships. The data obtained were statistically analysed.

RESULTS

The commonest position of the MF in the Rajasthan and NE populations was position 4 bilaterally, while in the Punjab population, it was position 3 on the right and position 4 on the left side. The majority of the MF was round in shape followed by oval. The mean distance between two MF was highest among the Punjab male population and least among the NE female population. The most frequent pattern of MF continuity with IDC was diffuse in Rajasthan population, separated in NE and continuous in Punjab. Correlation between Angle's molar relation with MF position was significant for Classes I and II but not for Class III. Correlation of inter-foramen distance between genders was highly significant in the NE and Punjab populations.

CONCLUSION

The commonest MF position was aligned with the 1st premolar and between the 1st and 2nd premolar.

Pyonephrosis due to Chryseobacterium gleum: a first case report

Chryseobacterium spp are widely distributed in nature but data of their isolation from clinical samples is scanty. Here, we report the first case of AmpC producing C. gleum causing pyonephrosis in a patient having bilateral nephrolithiasis on double J (DJ) stent. The present isolate was resistant to vancomycin, erythromycin, clindamycin, carbapenems and ciprofloxacin and susceptible to tetracycline and minocycline. The patient was treated with tetracycline and recovered without the need for removal of the DJ stent. The environmental surveillance carried out to trace the nosocomial origin of the isolate was negative. Since antimicrobial susceptibility of this isolate is different from previous reports, we emphasise that in vitro susceptibility testing should be sought to choose optimal antimicrobial agents for these Nonfermentative Gram-Negative Bacilli (NFGNBs) with different susceptibility patterns.

Effect of home-based light treatment on persons with dementia and their caregivers

Sleep disorders are problematic for persons with dementia and their family caregivers. This randomized controlled trial with crossover evaluated the effects of an innovative blue-white light therapy on 17 pairs of home-dwelling persons with dementia and their caregivers. Subjects with dementia received blue-white light and control ('red-yellow' light) for six weeks separated by a four-week washout. Neither actigraphic nor most self-reported sleep measures significantly differed for subjects with dementia. For caregivers, both sleep and role strain improved. No evidence of retinal light toxicity was observed. Six weeks of modest doses of blue-white light appear to improve sleep in caregivers but not in persons with dementia. Greater or prolonged circadian stimulation may be needed to determine if light is an effective treatment for persons with dementia.

Surgical outcomes of minimally invasive vitrectomy surgery in Eales' disease

INTRODUCTION

The results of surgical outcomes of 20 gauge pars plana vitrectomy in Eales' disease are available in the scientific literature. However, all these studies have been done using the 20 gauge vitrectomy systems and most studies have been conducted in a retrospective manner.

OBJECTIVE

To evaluate the outcomes and safety of 23 gauge vitrectomy in complications of Eales' disease.

MATERIALS AND METHODS

STUDY DESIGN

Consecutive interventional case series.

PARTICIPANTS

Seventy-six eyes of 72 nonconsecutive patients undergoing 23-gauge vitrectomy for complications of Eales' disease were enrolled. The participants were followed up for a minimum of one year.

INTERVENTION

The participants underwent a complete demographic, medical and ophthalmic evaluation. A 23-gauge vitrectomy was performed. Endotamponade was used when necessary. Perioperative and postoperative events were recorded. Primary outcome measures were visual acuity and complications arising due to surgery.

RESULTS

Indication for surgery was non-clearing vitreous hemorrhage in 89.4% (68/76) and secondary retinal detachment in 10.6% (8). Visual acuity improved from Log Mar 1.80 ± 0.19 units preoperatively to Log Mar 0.47±0.59. Best-corrected visual acuity equivalent to Snellen 6/9 was achieved in 77. 6% of eyes. . Surgical failure was seen in 6.5% cases. Four cases were lost due to progression to neovascular glaucoma and 1 case was lost to severe residual retinal detachment. Iatrogenic portside retinal breaks occurred in 3.9% (3), post-vitrectomy retinal detachment 2.6% ( 2), hypotony 1.3% (1) and cataract in 38.1% (28) cases.

CONCLUSION

23-gauge sutureless vitrectomy in patients with Eales' disease is a safe and effective technique with acceptable level of risk and complications.

Cutaneous T-cell lymphomas and their management strategies

Cutaneous T-cell lymphomas (CTCLs) comprise a heterogeneous group of lymphoproliferative disorders characterized by the proliferation of skin-homing post-thymic T-cells. It is the second most common extranodal non-Hodgekin's lymphoma. Many variants of mycosis fungoides and CTCLs are known to date, differing in clinical, histological, and immunophenotypic characteristics. Oral involvement has also been reported rarely in CTCLs. Treatment depends on the disease stage or the type of variant. New insights into the disease and the number of emerging novel therapeutic options have made it an interesting area for dermatologists and medical oncologists.

Oral Health Status, Treatment Needs and Knowledge, Attitude and Practice of Health Care Workers of Ambala, India - A Cross-sectional Study

Background:

Health care workers (HCWs) from an important component of the health care system of any nation. Adequate knowledge regarding oral health is also mandatory as it is directly related to general health. Aim: The present study was undertaken to assess oral health status and treatment needs of the health workers in Ambala district and to assess the knowledge, attitude and practices of HCWs.

Subjects and Methods:

A cross-sectional study was conducted among 148 HCWs of Ambala District. World Health Organization (WHO) Oral Health Performa-1997 was used to collect the data. For the diagnosis of dental caries, WHO type III examination was done using mouth mirrors and sharp probes while periodontal assessments were done by community periodontal index-probes. The data were analyzed using SPSS package, Chicago, IL, version 13.0.

Results:

Eating sweets and poor oral hygiene lead to dental caries were cited as the main reasons for dental caries by 62.2% (92/148) of subjects. Majority of the subjects (43.2%, 64/148) used to brush their teeth once a day. Mean number of decayed and missing teeth due to caries were 4.73 and 0.628 respectively. Prosthetic needs for maxillary arch were almost the same when compared to the prosthesis in the mandibular arch. Majority of the male (82.1%, 46/56) and female (79.3%, 73/92) subjects were having calculus.

Conclusion:

Attitude of the health workers toward oral health was poor as they had significantly higher treatment needs. The present study emphasized the need of regular dental checkup and health education of HCWs.

Clinical & immunological profile of newly diagnosed patients with youth onset diabetes mellitus

BACKGROUND & OBJECTIVES

There has been a rise in the incidence of diabetes mellitus in the younger population of India. There are limited data available on the immunological profile of youth onset diabetes mellitus (DM) especially in type 2. Therefore, this study was undertaken to evaluate the clinical and immunological profile of youth onset DM in north India.

METHODS

Fifty one consecutive patients of 8-35 yr of age with diabetes mellitus attending the Lok Nayak Hospital, Maulana Azad Medical College, New Delhi, and Hormone Care and Research Center at Ghaziabad, Uttar Pradesh, India, were included in the study. All subjects were tested for glutamic acid decarboxylase (GAD), an islet cell antigen ICA512/IA2, and insulin antibodies. GAD and ICA512/IA2 were done by ELISA and insulin autoantibodies were tested by radioimmunoassay (RIA) method. These patients were also screened for hepatitis A to E, cytomegalovirus (CMV) and Epstein-Barr virus (EBV) as trigger factors for onset of type 1 DM.

RESULTS

o0 f the total 51 patients, 38 were men and 13 were women. The mean age and BMI of the subjects was 19.7 (±7) years and 21 (± 5) kg/m [2] , respectively. Twenty patients were below the age of 18 yr and their height was more than 75 th percentile of Indian standards. All patients were symptomatic and 12 of these presented with ketoacidosis. Only 48 per cent (n=24) were positive for GAD, 14 per cent (n=7) for ICA512/IA-2, and 28% (n=14) were positive for insulin antibody. Five of these patients had evidence of hepatitis E virus infection. None of the subjects had evidence of active CMV or EBV infection.

INTERPRETATION & CONCLUSIONS

About half of the youth onset diabetes mellitus patients from north India had presence of pancreatic autoimmunity in the form of GAD, ICA512/IA2, and insulin antibodies or a combination of antibodies suggestive of having type 1 DM. Further studies need to be done on a large sample size in different parts of the country.

SAR studies of o-hydroxychalcones and their cyclized analogs and study them as novel inhibitors of cathepsin B and cathepsin H

Cathepsins have emerged as a potential target for anti-cancer drug development. In the present study, we have synthesized three structurally related series of flavanoids i.e., 2'-hydroxychalcones, flavanones and flavones and assayed in vitro to study their inhibitory potency against cathepsin B and H, promising drug candidate for cancer therapy. Enzyme kinetics studies were carried out in presence of these compounds after preliminary proteolytic studies on endogenous protein substrates. SAR studies suggested that open chain flavanoids were better inhibitors as compared to their cyclized analogs. The most potent inhibitors among the three series were nitro substituted compounds 1g, 2g and 3g with Ki values of ∼6.18×10(-8) M, 4.8×10(-7) M and 7.85×10(-7) M for cathepsin B and Ki values of ∼2.8×10(-7) M, 31.8×10(-6) M and 33.7×10(-6) M for cathepsin H, respectively. The relationship between chalcone, flavanones and flavone structures interpreted by docking studies on cathepsin B and H also provided useful insights.

Coexistence of Extended Spectrum Beta-Lactamases, AmpC Beta-Lactamases and Metallo-Beta-Lactamases in Acinetobacter baumannii from burns patients: a report from a tertiary care centre of India

Multidrug-resistant Acinetobacter baumanii is a major pathogen encountered in pyogenic infections, especially from burns patients in hospital settings. Often there is also coexistence of multiple beta-lactamase enzymes responsible for beta-lactam resistance in a single isolate, which further complicates treatment options. We conducted a study on burn wound pus samples obtained from the burns unit of our hospital. Phenotypic tests were used to determine the Extended Spectrum Beta-Lactamase, AmpC Beta-Lactamase and Metallo-Beta-Lactamase producing status of the isolates. Almost half of the samples from the burn wounds yielded Acinetobacter baumanii as the predominant pathogen (54.05%). Coexistence of the three resistance mechanisms was seen in 25 of the 100 (25%) isolates of Acinetobacter baumanii. This study emphasizes the need for the detection of isolates that produce these enzymes to avoid therapeutic failures and nosocomial outbreaks.

Attitudes and Awareness Regarding Hepatitis B and Hepatitis C Amongst Health-care Workers of a Tertiary Hospital in India

Background:

Hepatitis is an inflammatory disease of the liver. In sever cases, it may lead to permanent liver damage including liver cirrhosis or hepato-cellular carcinoma and may ultimately lead to death. Health-care workers (HCWs), due to their regular contact with patients are at a high-risk of acquiring this disease.

Aim:

The aim of this study was to assess the knowledge and attitude toward hepatitis B and C infection among the health-care interns and correlate the level of awareness to the attitude they behold toward the disease.

Subjects and Methods:

A closed ended questionnaire consisting of questions to evaluate the knowledge regarding hepatitis B and C infection and attitude of the (HCWs/interns) was duly filled by 255 participants including, 100 dental, 100 medical, and 55 nursing interns. Statistical analysis was carried out using the Chi-square test, ANOVA test, post-hoc test and Pearson's correlation.

Results:

Although most of the interns were aware of the existence of hepatitis B and C infection, the level of awareness regarding the modes of transmission and vaccination was found to be dissatisfactory. Awareness level regarding the infection among nursing interns was statistically significantly lower than the dental and medical interns. A direct positive correlation as found between awareness score and behavior score, which reveals that interns with better awareness level had better attitudes toward the infection and prevention of its transmission.

Conclusion:

There is an urgent need to increase the level and quality of training among HCWs to prevent the spread of hepatitis B virus and hepatitis C virus.

Investigating inspection practices of pharmaceutical manufacturing facilities in selected Arab countries: views of inspectors and pharmaceutical industry employees

There are few studies that explore inspection practices of pharmaceutical facilities from the viewpoint of inspectors and industry employees. In this descriptive, cross-sectional study, inspectors and quality assurance staff from 4 Arab countries--the United Arab Emirates, Saudi Arabia, Egypt and Jordan--were surveyed about their inspection practices and views. There was considerable variation in inspection practices across countries and between the inspectorate and quality assurance staff within countries. Divergence was found in views associated with payment mechanisms. There was mutual agreement by both groups that inspectors were in short supply and that they needed to be better trained. Inspectors appeared to have less authority than expected in order to control pharmaceutical manufacturing and marketing activities. Compounding this was a dearth of policy which would support a more uniform and systematic approach to the inspection process within and across countries.

Formulation development and dissolution rate enhancement of efavirenz by solid dispersion systems

The aim of this study was to enhance the dissolution rate of efavirenz using solid dispersion systems (binary and ternary). A comparison between solvent and fusion method was also investigated. Solid dispersions of efavirenz were prepared using polyethylene glycol 8000, polyvinylpyrrolidone K30 alone and combination of both. Tween 80 was incorporated to obtain a ternary solid dispersion system. Dissolution tests were conducted and evaluated on the basis of cumulative percentage drug release and dissolution efficiency. Physicochemical characterizations of the solid dispersions were carried out using differential scanning calorimetric, powder X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. Dissolution was remarkably improved in both systems compared to pure efavirenz (P<0.05). An optimum ratio was identified at a drug:polymer of 1:10. Incorporation of Tween 80 to 1:10 formulations formed using solvent method showed further improvement in the dissolution rate. Physicochemical characterization results suggested that efavirenz existed in the amorphous form in all the solid dispersion systems providing evidence of improvement in dissolution. No statistically significant difference (P>0.05) in dissolution was observed between the two methods. Binary and ternary solid dispersion systems both have showed a significant improvement in the dissolution rate of efavirenz. Formulations with only polyvinylpyrrolidone K30 showed best dissolution profile and 1:10 was identified as an optimum drug-polymer weight ratio.