Antibacterial Photodynamic Therapy of the Metallosurfactant-Fluorescein Conjugate under Visible Light Illumination.

Antibacterial photodynamic therapy (APDT) has received increased attention as a treatment for multidrug-resistant bacterial infections caused by antibiotic abuse. However, photosensitizers used in APDT have disadvantages such as water insolubility, self-aggregation, and photobleaching. To address these limitations, metal complexes have been explored. However, the use of such complexes tends to confine their antibacterial effectiveness specific bacterial strains. In this study, we report iron (Fe)- and copper (Cu)-based metallosurfactants as unique moieties for antibacterial photodynamic therapy (PDT) under the illumination of visible light. Briefly, our formulated Fe and Cu metallosurfactants, when combined with a fluorescein photosensitizer, exhibit nearly 100% antibacterial efficacy. This high efficiency is primarily attributed to the enhanced generation of singlet oxygen using FL in the presence of metallosurfactants when targeting bacteria such as Escherichia coli and Staphylococcus aureus under laser light. In vitro experiments further confirmed the superior antimicrobial activity of these metallosurfactants against a diverse range of microbial cultures, encompassing Gram-negative and Gram-positive bacteria as well as fungi. This performance outpaces conventional surfactants like cetyltrimethylammonium chloride and cetylpyridinium chloride. The compelling results from MTT assays and flow cytometry endorsed the substantial enhancement in antimicrobial properties achieved through Fe and Cu doping, all without the need for additional secondary agents. Notably, this synergistic antibacterial approach using metallosurfactants in PDT holds significant promise for the elimination of various bacteria in vivo, with the added advantage of mitigating the emergence of multidrug resistance.

Exploring Factors Responsible for Absenteeism among Undergraduate Medical Students.

Aim: The present study was conducted by for exploring factors responsible for absenteeism among undergraduate medical students. Materials and Methods: After taking students' views on why they thought lectures were important to them, a questionnaire was designed to explore the various factors responsible for absenteeism. Out of 150, 130 students filled the questionnaires and were taken into account for the calculation of data. Also, their recommendations on how to improve class attendance were recorded. All the results were analyzed. Results: Most of the students were of the opinion that lectures are important as they get to interact with teachers and peers, get timely feedback, and develop effective communication skills. The most common reason stated by male students for absenteeism was the long duration of lectures followed by dislike for the teaching style of teachers, while the female students missed classes mainly due to health issues and poor presentation skills of teachers. Conclusion: All these findings call for further research to determine a better understanding of the reasons for absenteeism and its consequences.

Herbal Approaches in the Management of Mental Depression.

BACKGROUND: Human's existence has become more stressful these days, most likely for the sake of improving one's lifestyle and fulfilling one's aspirations and needs. Depression is the most frequent neurological disorder, which affects millions of individuals worldwide. In clinical research, depression is the second most frequent chronic disease. A variety of herbal medications thought to have antidepressant-like effects have been reported in ancient pharmacopoeias from around the world. These provide several prospective chemicals that could be developed into modern mental medications while also causing no noticeable negative effects. OBJECTIVE: The review is written to provide herbal treatment and comprehensive information about depression. METHODS: Plants and plant formulations that were found effective in the treatment of depression are thoroughly reviewed. The antidepressant efficacies of medicinal plants, as well as their dosages, are investigated using experimental models. The review article contains 140 plants possessing antidepressant properties, 11 commercial formulations, and 25 active/isolated ingredients, as well as their chemical structure, which have been thoroughly reviewed with antidepressant activity after studying 283 references. RESULTS: Literature revealed that a variety of medicinal plants are effective for the treatment of depression such as Hypericum perforatum, Catha edulis, Tinospora cordifolia, Curcuma longa, Ferula foetida, Rhodio larosea, Glycyrrhiza glabra, Crocus sativus, Ocimumba silicum and Embelica officinalis. CONCLUSION: Potential compounds isolated from medicinal plants for the treatment of depressive disorders need to be established and herbal plant research could aid in this endeavour.

Case Based Learning in Teaching Pharmacology to Undergraduate Medical Students.

Background With the new competency-based curriculum coming into effect we need to introduce newer teaching-learning methods to help students improve their learning and acquire necessary knowledge and skills. Hence to integrate pharmacology with clinical sciences and involve the students in their learning process, case-based learning (CBL) has been found to be very successful. Therefore the present study was planned to introduce CBL as a new teaching-learning method in pharmacology and to know the perceptions of the students regarding this method.  Objectives The study aimed to introduce CBL to Bachelor of Medicine and Bachelor of Surgery (MBBS) students as a method of teaching pharmacology and the perceptions of the students regarding CBL were noted. Methodology After seeking institutional review board approval and sensitizing the students and faculty about this new teaching-learning method, CBL sessions were conducted on a few topics. Perceptions of the students were recorded on a feedback questionnaire and the results were analyzed. Results Ninety-five percent of students agreed that CBL helped in better comprehension of the concepts. Ninety-six percent of the students found CBL interesting and 96% of students said that CBL will help them correlate pharmacology clinically. Conclusions The students felt that CBL is an effective learning tool and would promote the clinical application of pharmacology.

Design and applications of metallo-vesicular structures using inorganic-organic hybrids.

In advanced biomedical diagnosis, various supramolecular assemblies based on inorganic-organic hybrids have found great interest as functional materials. These assemblies describe a new field of metallovesicles where the introduction of metal ions enables the chemical manipulation of assemblies in terms of their structural stability, redox activity, and pH stability. Additionally, they mimic the elaborative architecture of natural liposomal assemblies and exhibit hierarchical morphologies, and promise novel functions. With the constant developments in this field, various supramolecular assemblies such as MCsomes, Polymersomes, and Metallosomes, etc. came into existence. These hybrid assemblies have been utilized for several applications such as drug delivery, MRI contrasting, DNA delivery, and catalytic activity. The key advantage of these assemblies is their ability to deliver therapeutics to specific locations due to their biomimetic properties and release their contents at the desired time. Hence, they provide a valuable platform for the treatment of a variety of diseases. Through the present article, we intend to provide insights into the latest developments made in this field. This modularity underscores the tremendous promise of supramolecular assemblies as an emerging interdisciplinary research branch at the interface of chemistry and biological sciences.

Spherical silver oxide nanoparticles for fabrication of electrochemical sensor for efficient 4-Nitrotoluene detection and assessment of their antimicrobial activity.

This research article reports an economic and affordable microwave-assisted synthesis of spherical silver oxide nanoparticles (Ag2O NPs) (80-90 nm) for an efficient electrochemical sensing of a hazardous organic pollutant 4-nitrotoluene (4-NT). Such well-characterized Ag2O NPs were utilized to modify gold (Au) electrode in order to fabricate Ag2O-NPs/Au sensor to detect 4-NT using cyclic voltammetry (CV) and linear sweep voltammetry (LSV) techniques. Ag2O-NPs/Au sensor exhibited a distinguished electrical response as a function of varying 4-NT concentration in neutral medium samples. Ag2O-NPs/Au sensor demonstrated an ultrahigh sensitivity as 15.33 µA (µM)-1 cm-2, a low detection limit of 62.3 nM, and linear response in detection ranges of 0.6-5.9 µM and 37-175 µM. The sensing performance of fabricated Ag2O-NPs/Au sensor is reproducible, reusable, selective in presence of other chemical species, and validated using real samples. The Ag2O/Au sensor had much rapid and easy fabrication process and offered much lower LOD for 4-NT detection than many previously reported sensors. Along with efficient electrochemical activity, the spherical Ag2O NPs also exhibit remarkable antimicrobial activity against harmful gram negative Escherichia coli (E. coli) and gram positive Staphylococcus aureus (S. aureus) bacteria. Herein projected efficient Ag2O-NPs/Au electrochemical sensor for 4-NT is affordable with the capability of scaling up to perform point-of-care 4-NT testing needed for successful environmental monitoring and water quality assurance.

Solitary neurofibroma of maxilla: a rare clinical entity.

Neurofibroma (NF) is a benign tumour of the peripheral nervous system which is rare in head and neck region. Head and neck NF are mostly located in the soft tissue and rarely seen intraosseously. These may present either as solitary lesions or as part of the generalised syndrome of neurofibromatosis or von Recklinghausen's disease of the skin. The intraosseous ones are most commonly seen as solitary lesions, rather than part of neurofibromatosis. The following report describes a unique case of a solitary neurofibroma of the maxilla without generalised syndrome of neurofibromatosis in a male patient.

Fluorescein-Metal Hybrid Surfactant Conjugates as a Smart Material for Antimicrobial Photodynamic Therapy against Staphylococcus aureus.

Photodynamic therapy (PDT) has been extensively used as an effective alternative for the treatment of bacterial infection using photosensitizers (PSs) in the presence of appropriate light. However, the limitation in the effectiveness of PDT is because of the low yield of singlet oxygen from existing PSs because of their low solubility. Thus, we have developed a platform to enhance the solubility and the photodynamic activity of PSs against bacterial cells using metallosurfactants. Herein, we have used manganese metal-containing single- (MnC I) and double-chain metallosurfactants (MnC II) which show an interplay of electrostatic/hydrophobic interactions with fluorescein (FL) dye (as a PS) and when used in the presence of light enhances the PDT. These interactions play a significant role in enhancing the singlet oxygen generation efficiency of FL. MnC I and MnC II have shown good antimicrobial activity against Gram-positive Staphylococcus aureus (S. aureus) bacteria. More interestingly, these metallosurfactants when combined with FL significantly enhanced the affectivity against S. aureus, wherein 100% killing was achieved. As compared to experiments performed in the dark, the metallosurfactant, by enhancing the solubility of FL, increases the formation of singlet oxygen upon light irradiation and thus increases cell death. Therefore, the synergistic effect of FL (light toxicity) and metallosurfactants (dark toxicity) defined excellent reduction in the colony formation of bacteria. These results were corroborated through field-emission scanning electron microscopy and optical microscopy, where the rupturing of the cell wall of bacterial cells was observed during this therapy. Moreover, the binding of metallosurfactants to the genomic DNA of S. aureus was also evaluated by gel retardation analysis and UV-visible spectroscopy. The outcomes from this study will deliver formulations for PDT which can be used in clinical medical applications and cancer therapy in the future.

Synthesis, thermal and surface activity of cationic single chain metal hybrid surfactants and their interaction with microbes and proteins.

A series of water-soluble metal functionalized surfactants have been prepared using commercially available surfactant cetyl pyridinium chloride and transition metal salts. These complexes were characterized in the solid state by elemental analysis, FTIR, 1H NMR and thermogravimetric analysis. The interfacial surface activity and aggregation behaviour of the metallosurfactants were analysed through conductivity, surface tension and small angle neutron scattering measurements. Our results show that the presence of metal ions as co-ions along with counter ions favours micellization at a low critical micellization concentration (CMC). Small angle neutron scattering revealed that the metallomicelles are of a prolate ellipsoidal shape and exhibit strong counterion binding. This article further describes the interaction of the metallosurfactants with transport protein Bovine Serum Albumin (BSA) using different spectroscopic techniques. A spectroscopic study was used to study the binding, interaction and quenching mechanism of BSA with the metallosurfactants. Gel electrophoresis (SDS-PAGE) and circular dichroism (CD) investigated the structural and conformational changes produced in BSA due to the metallosurfactants. The results indicate that there is an alteration in the secondary structure of BSA due to the electrostatic interaction between positive head groups and metal co-ions of the metallosurfactants and negatively charged amino acids of BSA. As the concentration increases, the α-helicity of BSA decreases and all the three studied metallosurfactants gave comparable results. Finally, the in vitro cytotoxicity and antimicrobial activity of the metallosurfactants were evaluated against erythrocytes and microorganisms, which showed prominent effects related to the presence of a metal ion in metallomicelles of the hybrid surfactants.

Cationic double chained metallosurfactants: synthesis, aggregation, cytotoxicity, antimicrobial activity and their impact on the structure of bovine serum albumin.

Bovine serum albumin (BSA) is one of the most copious and significant blood proteins with dynamic structure. The understanding of the structural functionality of BSA and its interaction with metal ions is desired for various biological functions. Herein, three different metallosurfactants containing different transition metals and the same hydrophobic tail were engaged to investigate the structural transition of BSA. The metallosurfactants have been prepared by a combination of metal ions (M = Fe, Co and Ni) with cetylpyridinium chloride surfactant via the ligand insertion method and were characterized by elemental, FTIR, 1H-NMR, and thermogravimetric analysis (TGA). The obtained results reveal that insertion of a metal ion perturbs the aggregation behavior of the surfactant. Incorporation of a metal-ion has been found to decrease the CMC value of the surfactant, which has been supported by conductivity, surface tension and small angle X-ray scattering (SAXS). These metallosurfactants were employed to study the interaction and binding mechanism of BSA under physiological conditions. SDS-PAGE analysis points out a weak effect of metallosurfactants on the primary structure of BSA, whereas CD spectra implied a significant change in secondary structure with the decreased α-helical content of BSA. Fluorescence spectroscopy indicates the effect of metallosurfactants on the tertiary structure of BSA, whereas absorption spectra demonstrated static quenching with a blue shift in the presence of metallosurfactants. Moreover, unfolding of BSA in the presence of metallosurfactants has also been confirmed by SAXS studies. The overall results indicate that insertion of the metal ion into the framework of the surfactant structure enhances its protein binding/folding/unfolding abilities, which would be helpful in clinical as well as in life sciences.

Investigating the structural integrity of Bovine serum albumin in presence of newly synthesized metallosurfactants.

Bovine Serum Albumin is major transport protein and is often used as a drug carrier in body organs. Knowledge of its binding with metallosurfactant can significantly influence the biodistribution of metallodrugs. Current work demonstrated a facile method to prepare four different double chained metallosurfactants containing Fe, Co, Ni and Cu as part of their counter ion. The as-synthesized metallosurfactants were characterized using FTIR, AAS, TGA and XRD in solid form. The aggregation of these metallosurfactants in aqueous medium was investigated through conductivity, surface tension and SAXS. Further, we have investigated their binding with BSA through different analytical methods The effect of concentration of metallosurfactants on the primary and secondary structure of BSA was further examined by SDS-PAGE and Circular dichroism, respetively. It is found that at premicellar concentration, the primary structure of BSA was not affected but the secondary structure i.e. α-helical structure of BSA was altered as shown by circular dichroism. Interestingly, post micellar concentration of metallosurfactants shows the pronounced effect on the primary and secondary structure of BSA. SAXS study also supports the fact of unfolding of protein and its wrapping around the micelles. Zeta potential describes the electrical charge and stability of the protein in the presence of different concentration of metallosurfactant. Along with, it was found that presence of protein delays the aggregation behavior of metallosurfactant, as a sign of binding of BSA with metallosurfactant.

Fabrication of metalosomes (metal containing cationic liposomes) using single chain surfactants as a precursor via formation of inorganic organic hybrids.

Among the self-assembled forms of surfactants, vesicles/liposomes are a highly promising and interesting feature of surfactants, which are usually formed from water insoluble surfactants. Herein, we demonstrate the formation of liposomes from single-chain cationic surfactants with the help of metals as a part of the counter ion, and these metal embedded liposomes are termed as metalosomes. It is a noteworthy advancement in the area of self-assembled molecular structures since we report the preparation of metal embedded liposomes (metalosomes) from a water soluble single chain cationic surfactant, which is otherwise a property or an arrangement made by double tailed surfactants, or more precisely lipids that are poorly water soluble. We can use this method for various cationic surfactants and metal combinations and the studies are still in process. However, this preliminary report on manganese-based surfactants depicts the successful formation of cationic metalosomes (with/without cholesterol), and the formation, structure and size has been verified using TEM, FE-SEM, DLS XRD and SAXS. The comparison of metalosomes with reverse vesicles in different solvents further gave an insight of microstructure and solvent environment effects on the self-assembly of metallosurfactants. In addition, we have also evaluated the encapsulation ability of metalosomes for fluorescein dye. High encapsulation efficiency of Mn-somes makes them promising candidates for several applications, particularly because of its water solubility.

Computed Tomography in Craniofacial Fibrous Dysplasia: A Case Series with Review of Literature and Classification Update.

INTRODUCTION: Fibrous dysplasia (FD) is a fibroosseous lesion of the osseous structures of the body. It is not a commonly reported lesion yet it is considered as an important lesion which can affect the maxillofacial region as well. As a result, it can cause deformity of the jaw bones which can further lead to severe facial asymmetry. Craniofacial fibrous dysplasia (CFD) is one of the subtypes of FD that can affect the bones of the craniofacial complex, including the mandible and maxilla. It can also present as facial asymmetry and can be investigated with the help of Maxillofacial Radiology and Imaging. The radiographic findings may vary according to the extent and degree of the disease. Although conventional radiographs provide a good clue regarding the lesion, advanced maxillofacial imaging is capable of providing detailed extent of the disease. Furthermore the classification of CFD is not very clear in the literature. CASE REPORT: This particular paper attempts to document and report the CT appearance of CFD with an attempt to propose a better classification system for the same. Four different patients are reported which presented with FD with involvement of bones of craniofacial region. Working diagnosis of CFD was made with the help of clinical features as well as with radiographic assessment. Advanced imaging included CT scan of the lesions. The article highlights the importance of computed tomography in diagnosis as well as assessment of extent of the disease. CONCLUSION: It can be concluded that the Dental professionals must be aware regarding the different radiographic appearances of CFD. Advanced imaging modality like CT can provide with exact diagnosis as well as extent of the lesions like FD. Further collaboration of researchers is required to incorporate this proposed change in classification of CFD.

Effectiveness of Osteopathic Therapy in the Treatment of Oral Submucous Fibrosis.

Oral submucous fibrosis (OSMF) is a chronic progressive debilitating disease of oral cavity leading to the stiffness of oral mucosa, burning and trismus resulting in marked rigidity, and an inability to open the mouth. As the medical treatment of OSMF is yet not standardized, the purpose of the present case study was to explore the effectiveness of osteopathic manipulative treatment (OMT) in patients with OSMF. A 30-year-old male presented with a complaint of reduced mouth opening with burning sensation while eating spicy food for 4 years. The patient had undergone pharmacological treatment for the same in the past, got relief in the burning sensation, but did not get any significant improvement in mouth opening. Radiological features were noncontributory. The patient was treated with OMT techniques for twice a week for 4 weeks followed by the home exercise program. The patient showed a significant increase in mouth opening from approximately 10 mm to 22 mm of mouth opening at the end of the treatment sessions.

The fertilization-induced DNA replication factor MCM6 of maize shuttles between cytoplasm and nucleus, and is essential for plant growth and development.

The eukaryotic genome is duplicated exactly once per cell division cycle. A strategy that limits every replication origin to a single initiation event is tightly regulated by a multiprotein complex, which involves at least 20 protein factors. A key player in this regulation is the evolutionary conserved hexameric MCM2-7 complex. From maize (Zea mays) zygotes, we have cloned MCM6 and characterized this essential gene in more detail. Shortly after fertilization, expression of ZmMCM6 is strongly induced. During progression of zygote and proembryo development, ZmMCM6 transcript amounts decrease and are low in vegetative tissues, where expression is restricted to tissues containing proliferating cells. The highest protein amounts are detectable about 6 to 20 d after fertilization in developing kernels. Subcellular localization studies revealed that MCM6 protein shuttles between cytoplasm and nucleoplasm in a cell cycle-dependent manner. ZmMCM6 is taken up by the nucleus during G1 phase and the highest protein levels were observed during late G1/S phase. ZmMCM6 is excluded from the nucleus during late S, G2, and mitosis. Transgenic maize was generated to overexpress and down-regulate ZmMCM6. Plants displaying minor antisense transcript amounts were reduced in size and did not develop cobs to maturity. Down-regulation of ZmMCM6 gene activity seems also to affect pollen development because antisense transgenes could not be propagated via pollen to wild-type plants. In summary, the transgenic data indicate that MCM6 is essential for both vegetative as well as reproductive growth and development in plants.

The Etched1 gene of Zea mays (L.) encodes a zinc ribbon protein that belongs to the transcriptionally active chromosome (TAC) of plastids and is similar to the transcription factor TFIIS.

Etched1 (et1) is a pleiotropic, recessive mutation of maize that causes fissured and cracked mature kernels and virescent seedlings. Microscopic examinations of the et1 phenotype revealed an aberrant plastid development in mutant kernels and mutant leaves. Here, we report on the cloning of the et1 gene by transposon tagging, the localization of the gene product in chloroplasts, and its putative function in the plastid transcriptional apparatus. Several alleles of Mutator (Mu)-induced et1 mutants, the et1-reference (et1-R) mutant, and Et1 wild-type were cloned and analyzed at the molecular level. Northern analyses with wild-type plants revealed that Et1 transcripts are present in kernels, leaves, and other types of tissue, and no Et1 expression could be detected in the et1 mutants analyzed. The ET1 protein is imported by chloroplasts and has been immunologically detected in transcriptionally active chromosome (TAC) fractions derived from chloroplasts. Accordingly, the relative transcriptional activity of TAC fractions was significantly reduced in chloroplasts of et1-R plants. ET1 is the first zinc ribbon (ZR) protein shown to be targeted to plastids. With regard to its localization and its striking structural similarity to the eukaryotic transcription elongation factor TFIIS, it is feasible that ET1 functions in plastid transcription elongation by reactivation of arrested RNA polymerases.