Current Developments in Antimicrobial Surface Coatings for Biomedical Applications

Bacterial adhesion and subsequent biofilm formation on material surfaces represent a serious problem in society from both an economical and health perspective. Surface coating approaches to prevent bacterial adhesion and biofilm formation are of increased importance due to the increasing prevalence of antibiotic resistant bacterial strains. Effective antimicrobial surface coatings can be based on an anti-adhesive principle that prevents bacteria to adhere, or on bactericidal strategies, killing organisms either before or after contact is made with the surface. Many strategies, however, implement a multifunctional approach that incorporates both of these mechanisms. For anti-adhesive strategies, the use of polymer chains, or hydrogels is preferred, although recently a new class of super-hydrophobic surfaces has been described which demonstrate improved anti-adhesive activity. In addition, bacterial killing can be achieved using antimicrobial peptides, antibiotics, chitosan or enzymes directly bound, tethered through spacer-molecules or encased in biodegradable matrices, nanoparticles and quaternary ammonium compounds. Notwithstanding the ubiquitous nature of the problem of microbial colonization of material surfaces, this review focuses on the recent developments in antimicrobial surface coatings with respect to biomaterial implants and devices. In this biomedical arena, to rank the different coating strategies in order of increasing efficacy is impossible, since this depends on the clinical application aimed for and whether expectations are short- or long term. Considering that the era of antibiotics to control infectious biofilms will eventually come to an end, the future for biofilm control on biomaterial implants and devices is likely with surface-associated modifications that are non-antibiotic related.

Awareness, Practices and Treatment Seeking Behavior of Type 2 Diabetes Mellitus Patients in Delhi

Background:

Type 2 diabetes mellitus is a multisystem disorder that is associated with number of complications. Patient's awareness and practices are crucial components in reducing the burden of diseases and its complications.

Aim:

To assess patient's knowledge about their disease and its complications, practices, treatment seeking behavior and average expenditure incurred by its management.

Subjects and Methods:

A community based cross-sectional study was conducted in rural and urban slum areas of Delhi selecting a total of 98 diabetic patients diagnosed during the two community surveys and interviewed using pretested and predesigned questionnaire. Data were analyzed using SPSS software, version 17 (Chicago II, USA). Chi-square, fisher or Mann–Whitney tests were used for test of significance and considered statistically significant at P < 0.05.

Results:

Of 98 participants, 31.6% (31/98) were from urban slum area, and 68.4% (67/98) were from the rural area. In both urban and rural areas, majority were Hindu, married, literate and unemployed. Significantly less subjects (61.3%, 19/31) of urban slum area than of rural area (85.1%, 57/67) could name at least one complication of DM (P < 0.01, odds ratio [OR] =3.6, 95% confidence interval [CI] =1.3–9.6). Majority of participants in both urban slum and rural area have knowledge about at least one component of management but significantly lesser in urban (83.9%, 26/31) than rural area (97.0%, 65/67) were reported (P = 0.02, OR = 6.2, 95% CI = 1.1–34.2). Significantly more subjects (29.0%, 9/31) in urban slum area than rural areas (7.5%, 5/67) reported that they were not taking any treatment for DM (P < 0.01, OR = 0.2, 95% CI = 0.1–0.6). In urban area, 32.2% (10/31) patients told that it is a burden on their family while in rural area 44.7% (30/67) of the patients told that they have to squeeze money from the family expenditure to afford drugs.

Conclusion:

Patients need to be made aware of the asymptomatic phase of DM and its long term complications. At the same time, efforts should be made to sensitize them about the importance of taking regular treatment and management.

Development and validation of different ultraviolet-spectrophotometric methods for the estimation of besifloxacin in different simulated body fluids

In the present study a simple, accurate, precise, economical and specific UV-spectrophotometric method for estimation of besifloxacin in bulk and in different pharmaceutical formulation has been developed. The drug shows maximum λ_max289 nm in distilled water, simulated tears and phosphate buffer saline. The linearity range of developed methods were in the range of 3-30 μg/ml of drug with a correlation coefficient (r²) 0.9992, 0.9989 and 0.9984 with respect to distilled water, simulated tears and phosphate buffer saline, respectively. Reproducibility by repeating methods as %RSD were found to be less than 2%. The limit of detection in different media was found to be 0.62, 0.72 and 0.88 μg/ml, respectively. The limit of quantification was found to be 1.88, 2.10, 2.60 μg/ml, respectively. The proposed method was validated statically according to International Conference on Harmonization guidelines with respect to specificity, linearity, range, accuracy, precision and robustness. The proposed methods of validation were found to be accurate and highly specific for the estimation of besifloxacin in different pharmaceutical formulations.

Indigenous traditional knowledge and usage of folk bio-medicines among Rongmei tribe of Tamenglong district of Manipur, India

BACKGROUND

Rongmei tribe (Kooki), are inhabitant of the Charoi Chagotlong village, Tupul, Tamenglong district of Manipur have the traditional knowledge of folk bio-medicine based on diverse plant species for the prevention and cure of certain chronic diseases. The aim of this study was to document and preserve the indigenous knowledge of the Rongmei tribe on folk medicines.

MATERIAL AND METHODS

The present work was based on methodical field survey conducted between 2010, to 2013. Local people of within 30-70 age groups of both sexes were interviewed and a group discussion (using a structured interview schedule), was held to know about the type of plant parts used in folk bio-medicines, and their mode of use. The interviewers were drawn from a wide array of disciplines (Vendors, Farmers club, NGO's, scientific societies, etc.), to obtain maximum information in relation to folk bio-medicine.

RESULTS

A total of 60 species belonging to 36 different families (ranging from gymnosperm to angiosperm with medicinal benefits), were discussed briefly with significant emphasis on their local name, scientific name, family, parts used; they claimed to cure various ailments from these plants in this mode of folk bio-medicine. The different plant parts used were leaves, fruits, bulbs, bark, roots, seeds, tuber, trunk, flower, shoot, whole plant, rhizome, stem, wood and berries. Based on a life form of the reported plants comprise herbs, shrubs, trees, grasses, bulb, vine, climber, tuber and succulent.

CONCLUSION

Efforts should be made to promote the use of traditional biomedicines within rural communities to preserve the traditional knowledge.

Neuroimaging features and predictors of outcome in eclamptic encephalopathy: a prospective observational study

BACKGROUND AND PURPOSE

Posterior reversible encephalopathy syndrome is associated with eclampsia. We assessed the distribution and nature of typical and atypical cranial MR imaging findings in these patients and their correlation with clinical and laboratory data and predictors of outcome.

MATERIALS AND METHODS

Forty-five clinically confirmed cases of eclampsia were included in this prospective observational study. Subjects with hemolysis, elevated liver enzymes, and low platelets syndrome (n = 9) and pre-existing neurologic conditions (1 with cerebral solitary cysticercus granuloma) were excluded. Patients underwent blood investigations and cranial MR imaging.

RESULTS

Twenty-seven patients had abnormal while 8 had normal MR imaging findings. Involvement of brain regions was as follows: frontal, 88.89%; temporal, 44.44%; parietal, 100%; occipital, 100%; deep gray matter, 29.63%; cerebellum, 22.22%; brain stem, 14.81%. Cytotoxic edema was present in 33.33% of cases; 66.67% of patients had mild posterior reversible encephalopathy syndrome; 25.92% had moderate posterior reversible encephalopathy syndrome; and 7.41% had severe posterior reversible encephalopathy syndrome. Abnormal neuroimaging findings were significantly associated with altered sensorium; visual disturbances; status epilepticus; and elevated serum creatinine, uric acid, and lactate dehydrogenase (P=.006, P=.018, P=.015, P=.019, P=.003, and P=.001, respectively). Serum creatinine, uric acid, and lactate dehydrogenase values and the presence of moderate or severe posterior reversible encephalopathy syndrome were significantly associated with mortality (P<.001, P<.001, P=.009, and P=.027, respectively).

CONCLUSIONS

Neuroimaging in eclampsia demonstrates a higher incidence of atypical distributions and cytotoxic edema than previously thought. Altered sensorium; visual disturbances; status epilepticus; and elevated serum uric acid, lactate dehydrogenase, and creatinine are associated with abnormal neuroimaging findings. Higher serum creatinine, uric acid, and lactate dehydrogenase levels and moderate and severe forms of posterior reversible encephalopathy syndrome are possible predictors of poor outcome.

Students’ Reflections on Teaching Methodology in Anatomy

Objective: With technological evolution, use of power point presentation has been increased tremendously for classroom teachings in medical education. There is dearth of information that whether this technology is really liked by the students in anatomy or not. Therefore present study was conducted to assess which methodology of teaching anatomy was preferred by students: traditional (chalk & black-board), computer assisted or both when combined. Methods: A questionnaire based study was conducted that involved 250 1st year MBBS students. Students were asked to fill semi structured questionnaire that contained closed and open ended questions regarding teaching methodology. Results & Conclusion: 70.37% students favored combination of power point presentations along with traditional method, 25.93% preferred chalk and blackboard method and only 3.7% students opined that power point presentations should be the sole method of teaching. Therefore the study concludes that traditional method of lecture delivery in anatomy should be carefully amalgamated with power point presentations to meet the aspirations of students and to combat the limitations of chalk and board method. DOI: http://dx.doi.org/10.3126/ajms.v5i1.8039 Asian Journal of Medical Science Vol.5(1) 2014 pp.47-51

Apatite accumulation enhances the mechanical property of anammox granules

The strength of granular sludge is essential for the mechanical stability of the granules. Inorganic precipitants form a major factor influencing the strength of the granules. To check the possibility of apatite accumulation in anammox granules, and study its contribution to the mechanical strength of granules, anammox granular sludge was collected from Dokhaven municipal wastewater treatment plant, the Netherlands. Mineral precipitation inside the granules was visualized by micro-computed tomography, and apatite was identified by electron probe microanalysis and X-ray powder diffraction. The mechanical strength of anammox granules was measured by a low load compression tester. The contribution of apatite to the mechanical strength was evaluated by the generalized Maxwell model. Ca-PO4 minerals are reported to accumulate in anammox granules. A transformation of Ca-PO4 happens, and apatite is the final stable form. The accumulation of apatite increases the mechanical strength of anammox granules. A fast method to monitor and evaluate the accumulation of minerals in anammox granules was proposed.

Meta-analysis: serological markers and the risk of acute and chronic pouchitis

BACKGROUND

Serological markers such as anti-neutrophil cytoplasmic antibody (ANCA) and anti-Saccharomyces cerevisiae antibody (ASCA) may be associated with pouchitis after ileal pouch-anal anastomosis (IPAA).

AIM

To perform a systematic review with meta-analysis of studies evaluating the association of ANCA and ASCA status with risk of acute and chronic pouchitis after IPAA.

METHODS

We searched multiple databases (upto September 2012) for studies reporting ANCA and/or ASCA status along with risk of acute or chronic pouchitis after IPAA in adults with ulcerative colitis (UC). We abstracted odds ratio (OR) or raw data from the individual studies to calculate summary OR estimates with 95% CIs using random-effects model.

RESULTS

Eight studies reporting 184 cases of acute pouchitis and six studies reporting 151 cases of chronic pouchitis were included. The odds of chronic pouchitis were 76% higher in ANCA-positive patients than ANCA-negative (six studies; OR: 1.76; 95% CI: 1.19-2.61; P < 0.01). ASCA-positivity was not associated with the risk of chronic pouchitis (three studies; OR: 0.89; 95% CI: 0.49-1.59; P = 0.68). Neither ANCA (eight studies; OR: 1.54; 95% CI: 0.79-3.02; P = 0.21) nor ASCA-positivity (two studies; OR: 1.28; 95% CI: 0.25-6.54; P = 0.77) were associated with the risk of acute pouchitis.

CONCLUSIONS

The risk of chronic pouchitis after IPAA is higher in ANCA-positive patients, but the risk of acute pouchitis is unaffected by ANCA status. ASCA status was not associated with the risk of acute or chronic pouchitis. This information may be used to counsel UC patients regarding their risk of pouchitis after IPAA.

Investigations of bi-directional flow behaviour in presence of a large vertical opening in a fire compartment

In the complex thermal hydraulics codes developed for fire, reactor and containment safety the junctions in the multi-compartment geometries are often modeled as uni-directional junctions and some construct of flow coefficient. However, certain large size junctions are known to depict bi-directional flow behaviour under specific circumstances. The CFD based computer code FDS was used for an earlier reported study of fire in an enclosure on the bidirectional flow behaviour in present of a wall opening. Numerical simulation is directed to monitor the entrainment of the fresh air from outside to the fire compartment and resulting plume deflection due to presence of a big opening. The paper presents the details of the analysis, the results obtained, and comparison with the reported experimental data in terms of plume deflection, entrainment. Detailed investigations have been carried out to understand the bi-directionality of a junction by analyzing studying the outgoing hot air flow and incoming cold air.

Profile of lung cancer in predominantly Bidi smoking rural population of northern Himachal Pradesh

BACKGROUND

Lung cancer is a leading cause of morbidity and mortality among both genders. The histopathological patterns of lung cancer in different parts of India appear to be variable.

OBJECTIVE

To study the profile of lung cancer in northern Himachal Pradesh.

METHODS

Patients of all age groups and either gender with history and complaints suggestive of lung cancer were subjected to further investigations to study the histopathological types of lung cancer over a period of 14 months.

RESULTS

Out of 105 histopathologically confirmed patients with lung cancer (mean age 62.7 +/- 11.6 years; 96 males), 89.5% were "ever smokers" and 82.9% were "current smokers"; 92% of current smokers were bidi smokers. Most common presenting complaints were chest pain (46.7%) and cough (35.2%). Mean duration of longest presenting complaint was 64 days. The histopathological types included squamous cell carcinoma (37.1%), adenocarcinoma (36.2%), small cell carcinoma (8.6%), un-classifiable (16.2%), and other types (1.9%).

CONCLUSIONS

Majority of the lung cancer patients in northern Himachal Pradesh were bidi smoking males from rural areas and the incidence of adenocarcinoma and squamous cell carcinoma is almost equal.

Histopathological pattern of abnormal uterine bleeding in endometrial biopsies

Abnormal uterine bleeding is a common presenting complaint in gyanecology out patient department. Histopathological evaluation of the endometrial samples plays a significant role in the diagnosis of abnormal uterine bleeding. This study was carried out to determine the histopathological pattern of the endometrium in women of various age groups presenting with abnormal uterine bleeding. Endometrial biopsies and curettings of patients presenting with abnormal uterine bleeding was retrospectively studied. A total of 403 endometrial biopsies and curettings were analyzed. The age of the patients ranged from 18 to 70 years. Normal cyclical endometrium was seen in 165 (40.94%) cases, followed by 54 (13.40%) cases of disordered proliferative endometrium and 44 (10.92%) cases of hyperplasia. Malignancy was seen in 10 (2.48%) cases. Hyperplasia and malignancy were more common in the perimenopausal and postmenopausal age groups. Histopathological examination of endometrial biopsies and curettings in patients presenting with abnormal uterine bleeding showed a wide spectrum of changes ranging from normal endometrium to malignancy. Endometrial evaluation is specially recommended in women of perimenopausal and postmenopausal age groups presenting with AUB, to rule out a possibility of any preneoplastic condition or malignancy.

The chemical and mechanical differences between alginate-like exopolysaccharides isolated from aerobic flocculent sludge and aerobic granular sludge

This study aimed to investigate differences in the gel matrix of aerobic granular sludge and normal aerobic flocculent sludge. From both types of sludge that fed with the same municipal sewage, the functional gel-forming exopolysaccharides, alginate-like exopolysaccharides, were isolated. These two exopolysaccharides were chemically fractionated, and investigated by FT-IR spectroscopy. The isolated polymers were made into a gel by calcium addition and the mechanical properties of these reconstituted gels were measured by a low load compression tester. The viscoelastic behavior of the gels was described by a generalized Maxwell model. The alginate-like exopolysaccharides derived from aerobic granules had significantly higher amount of poly(guluronic acid) blocks but lower amount of poly(guluronic acid-manuronic acid) blocks in the chemical structure, while the alginate-like exopolysaccharides derived from aerobic flocculent sludge had equal amount of poly(guluronic acid) blocks and poly(guluronic acid-manuronic acid) blocks. These differences result in a perfect gel-forming capability of alginate-like exopolysaccharides derived from aerobic granules and bestowed this exopolysaccharides gel a stronger mechanical property as compared to alginate-like exopolysaccharides derived from aerobic flocculent sludge. The different chemical and mechanical properties of these two exopolysaccharides contributed to the distinguished characteristics between aerobic granular sludge and aerobic flocculent sludge.

Design and performance of hybrid constructed wetland systems for high-content wastewater treatment in the cold climate of Hokkaido, northern Japan

The performance of six multistage hybrid constructed wetland systems was evaluated. The systems were designed to treat four kinds of high-content wastewater: dairy wastewater (three systems, average inflow content 2,400-5,000 mg·COD l(-1), 3-6 years of operation); pig farm wastewater, including liquid food washing wastewater (one system, 9,500 mg·COD l(-1), 3 years); potato starch processing wastewater (one system, 20,000-60,000 mg·COD l(-1), 3 years); and wastewater containing pig farm swine urine (one system, 6,600 mg·COD l(-1), 2.8 years) (COD = chemical oxygen demand). The systems contained three or four vertical (V) flow beds with self-priming siphons and surface partitions and no or one horizontal (H) flow bed (three to five beds). In some V flow beds, treated effluents were recirculated (Vr) through the inlet to improve performance. Mean annual temperature was 5-8 °C at all locations. To overcome clogging due to the high load in a cold climate, we applied a safety bypass structure and floating cover material to the V flow beds. Calculated average oxygen transfer rates (OTRs) increased proportionally with the influent load, and the OTR value was Vr > V> H. The relations of load-OTR, COD-ammonium, and a Arrhenius temperature-dependent equation enable the basic design of a reed bed system.

Tomato leaf curl Joydebpur virus: a monopartite begomovirus causing severe leaf curl in tomato in West Bengal

A begomovirus was isolated from tomato plants showing leaf curl and stunting symptoms in farmers' fields near the district of Kalyani, West Bengal, India. Viral genomic components amplified by rolling-circle amplification were cloned and sequenced. The genome organization of this virus was found to be similar to those of Old World monopartite begomovirus, with DNA A and a betasatellite component. Neither alphasatellite nor DNA B component was detected. The begomovirus showed highest sequence identity of 93.6% to tomato leaf curl Joydebpur virus (ToLCJoV-[IN:Kal:Chi:06]) and was thus identified to be an isolate of ToLCJoV. The betasatellite isolated from these samples was identified as tomato leaf curl Joydebpur betasatellite. ToLCJoV-[IN:Kal:Tom:08] alone induced severe symptoms in Solanum lycopersicum, N. benthamiana and N. glutinosa plants, and its severity was enhanced when co-inoculated with the cognate betasatellite. ToLCJoV-[IN:Kal:Tom:08] trans-replicated four more non-cognate betasatellites and induced severe symptoms in N. benthamiana and tomato. Since DNA A replicated efficiently and caused systemic symptom expression, it is hypothesized that ToLCJoV is essentially a monopartite virus, which could have acquired a betasatellite from an unknown source.

Can low dose spinal anesthesia combined with ultrasound guided bilateral ilioinguinal-iliohypogastric nerve blocks avoid use of additional epidural catheter in high risk obstetric cases? Our experience from two cases

Critical obstetric cases associated with cardiac pathology may pose real challenge for anaesthesiologist during Caesarean section. Meticulous perioperative care and suitable selection of anaesthesia technique are the key to successful outcome. Single shot spinal anaesthesia is not used any more because of serious haemodynamic consequence. Progressive and controlled epidural local anaesthetic injection is mostly used in such cases. But recently combined spinal epidural anaesthesia and continuous spinal anaesthesia are suggested due to better precise control of haemodynamics and quicker onset. However, institution of such complex technique may require time which may not be feasible in emergency situations. Use of bilateral ilioinguinal-iliohypogastric nerve block along with low dose spinal anaesthesia may obviate the need of additional epidural catheter in such complicated cases. We hereby present our experience from two cases.

Role of serotonin in seasonal affective disorder

This review was prepared with an aim to show role of serotonin in seasonal affective disorder. Seasonal affective disorder, which is also called as winter depression or winter blues, is mood disorder in which persons with normal mental health throughout most of the year will show depressive symptoms in the winter or, less commonly, in the summer. Serotonin is an important endogenous neurotransmitter which also acts as neuromodulator. The least invasive, natural, and researched treatment of seasonal affective disorder is natural or otherwise is light therapy. Negative air ionization, which acts by liberating charged particles on the sleep environment, has also become effective in treatment of seasonal affective disorder.  

Development, characterization and solubility study of solid dispersions of Cefuroxime Axetil by the solvent evaporation method

Cefuroxime Axetil (Poorly water soluble drug), when prepared as solid dispersion showed improved solubility and dissolution. Therefore, the main purpose of this investigation was to increase the solubility and dissolution rate of Cefuroxime Axetil by the preparation of its solid dispersion with urea, using the solvent evaporation method. Physical mixtures and solid dispersions of Cefuroxime Axetil were prepared by using urea as a water-soluble carrier in various proportions (1:1, 1:2, 1:3, 1:4, 1:5, 1:6, and 1:7 by weight), by employing the solvent evaporation method. The drug release profile was studied and it was found that the dissolution rate and the dissolution parameters of the drug from the physical mixture as well as solid dispersion were higher than those of the intact drug. The Fourier Transform Infrared (FTIR) spectra revealed no chemical incompatibility between the drug and urea. Drug-polymer interactions were investigated using differential scanning calorimetry (DSC) and Powder X-Ray Diffraction (PXRD).

Functional characterization of βC1 gene of Cotton leaf curl Multan betasatellite

Whitefly-transmitted Begomoviruses having circular single stranded DNA genome cause severe leaf curl diseases in the tropical and subtropical region. The majority of Old World monopartite begomoviruses with DNA A component is associated with a satellite DNA of 1.3 kb length referred to as betasatellites. The presence of betasatellite is required to express typical symptoms in the primary hosts. Increased symptom expression in betasatellite's presence is attributed to a 13-15 kDa βC1 protein encoded by the βC1 gene on complementary sense strand. The exact mechanism by which the βC1 protein contributes to the symptoms' severity and helper viral DNA's accumulation is not yet understood. Here, we studied the βC1 protein of Cotton leaf curl Multan betasatellite, associated with mono and bipartite begomoviruses. The βC1 protein was expressed in prokaryotic system as 6XHis-βC1 fusion protein and recombinant protein showed size- and sequence-specific DNA binding activity. The host proteins which may interact with βC1 were identified by binding βC1 recombinant protein with heptapeptide in phage display library. The βC1-interacting host proteins predicted belong to metabolic and defense pathways, indicating that βC1 protein has a pivotal role in viral pathogenicity.

Rheological evaluation of thermoreversible and mucoadhesive nasal gels of Zolmitriptan

BACKGROUND AND OBJECTIVES

Rheological evaluation of thermoreversible mucoadhesive nasal gel of zolmitriptan is done to determine the steady shear behaviour and gelation temperature. The thermoreversible mucoadhesive polymers are sucessesfully used to increase the contact time of the therapeutic compound in the nasal cavity as well as they cause enhancement in permeation of drug through the nasal mucosa.

MATERIAL AND METHODS

Pluronic (F127) and Pluronic (F 68) were used as thermoreversible polymers in combination with a mucoadhesive polymer obtained from natural resource Zolmiriptan anti migraine drug obtained from Cipla Ltd. Rheometer Brookfield R/S- CPS- PI having cone-and-plate geometry was used for steady shear behaviour study and the gelation temperature was determined by Brookfield R/S plus Rheometer (Brookfield viscometer Ltd, Harlow, Essex, UK) fitted with spindle and Eurotherm cone/plate geometry.

RESULTS

Steady shear behaviour study concludes as content of mucoadhesive polymer starts increasing subsequently the viscosity of the solution starts increasing in the same manner. Gelation temperature study suggests that as the mucoadhesive content was increased in formulation the gelation temperature of the formulation was decreased subsequently. So it was concluded from the study that gelation temperature of the formulation was influenced by the mucoadhesive content. Temperature increases the gelation time of the formulation.

CONCLUSIONS

Above studies indicate that even small difference in the composition of the thermoreversible mucoadhesives gel formulations may cause major change in the rheological behaviour. Although the gelation temperatures of all the three formulations L1, L2 and L3 were below the human nasal temperature, they show different responses to the varied shear rates at different temperatures below and above the temperature of nasal cavity.