Development in the Synthesis of Bioactive Thiazole-Based Heterocyclic Hybrids Utilizing Phenacyl Bromide

Heterocyclic hybrid frameworks represent a burgeoning domain within the realms of drug discovery and medicinal chemistry, attracting considerable attention in recent years. Thiazole pharmacophore fragments, inherent in natural products such as peptide alkaloids, metabolites, and cyclopeptides, have demonstrated a broad spectrum of pharmacological potentials. Given their profound biological significance, a plethora of thiazole-based hybrids have been synthesized through the conjugation of thiazole moieties with bioactive pyrazole and pyrazoline fragments. This review systematically presents a compendium of robust methodologies for the synthesis of thiazole-linked hybrids, employing the (3 + 2) heterocyclization reaction, specifically the Hantzsch-thiazole synthesis, utilizing phenacyl bromide as the substrate. The strategic approach of molecular hybridization has markedly enhanced drug efficacy, mitigated resistance to multiple drugs, and minimized toxicity concerns. The resultant thiazole-linked hybrids exhibit a myriad of medicinal properties viz. anticancer, antibacterial, anticonvulsant, antifungal, antiviral, and antioxidant activities. This compilation of methodologies and insights serves as a valuable resource for medicinal chemists and researchers engaged in the design of novel thiazole-linked hybrids endowed with therapeutic attribute.

Real-time ultrasound-guided mid-thoracic epidural access using a novel paramedian cross (PX) view and drip infusion technique: a brief technical report

BACKGROUND

Real-time ultrasound guidance (USG) has been applied for lower thoracic epidural access, but the more challenging mid-thoracic epidural (MTE) access remains underexplored. This report presents a technique of real-time US guidance with a novel paramedian cross view, termed "the PX view," for securing MTE catheters, along with an outcome analysis from a retrospective case series.

METHODS

Medical records of patients who underwent USG-MTE catheter placement with the PX view and drip infusion technique from January to December 2022 were reviewed. All catheters were placed with patients in the prone position under mild to moderate procedural sedation. The process of acquiring the PX view, in-plane needling technique, and the use of drip infusion to identify loss of resistance were detailed. The incidence of successful PX view attainment, the number of attempts, redirections, failures, and any technique-related complications were recorded.

RESULTS

Fifty-one patients underwent USG-MTE catheter attempts, (42 with median sternotomy, 3 fractured ribs, 3 upper abdominal laparotomies, 2 modified radical mastectomies, and 1 thoracotomy). A satisfactory PX view was obtained in all patients, and the epidural space was identified during the first needle entry in 49 cases, resulting in a 96% first-attempt success rate. Seven patients required needle redirections, while two patients needed a second needle entry. No technique-related complications were documented.

CONCLUSION

The combination of the PX view and the drip infusion method proved effective for real-time ultrasound-guided MTE catheter placement.

Advances in Aβ imaging probes: a comprehensive study of radiolabelled 1,3-diaryl-2-propen-1-ones for Alzheimer's disease: a review

Alzheimer's disease (AD) is a formidable neurodegenerative disorder characterized by cognitive decline, memory impairment and inability to perform everyday tasks. In the pursuit of innovative diagnostic and therapeutic strategies, the synthesis and application of radiolabelled compounds have garnered significant attention. This review delves into the synthesis and biological significance of radiolabelled 1,3-diaryl-2-propen-1-ones, commonly known as chalcones, as Aβ imaging probes for AD. These versatile chalcone derivatives have demonstrated noteworthy potential as radiotracers for visualizing Aβ imaging probes, which are hallmark pathologies of AD. This review encompasses an exploration of chalcone synthesis via diverse methodologies and their biological implications, both as standalone entities and as precursors for intricate natural products. In addition, the pivotal role of advanced imaging techniques, such as single-photon emission computed tomography (SPECT) and positron emission tomography (PET), using various radioisotopes is highlighted. The use of radiopharmaceutical agents, including [18F]FDG, [18F]FMAPO, [11C]6-Me-BTA-1, [124/125I]IBETA, and [64Cu]YW-7 as potent tools for early diagnosis and therapeutic advancement is explored. This review underscores the critical nexus between radiolabelled chalcones and their pivotal role in advancing diagnostic and therapeutic paradigms in AD research. Furthermore, this study encapsulated the role of radiolabelled chalcone emphasizing their prospective implications for drug development and therapeutic interventions. A focal point of paramount significance is the elucidation of Aβ imaging probes and its important role in the combat against AD, with a particular emphasis on their role in facilitating early diagnosis and fostering advancements in therapeutic strategies.

Unravelling the synthetic and therapeutic aspects of five, six and fused heterocycles using Vilsmeier-Haack reagent

The aim of this review is to encapsulate the synthetic protocols and medicinal aspects of a wide range of heterocyclic compounds using the Vilsmeier-Haack (V. H.) reagent. These derivatives act as excellent precursors having different aryl ring functionalities and could be used for the synthesis of a variety of heterocyclic scaffolds. The V. H. reagent, a versatile reagent in organic chemistry, is used to formylate various heterocyclic compounds of medicinal interest. Due to the different chemical interactions, efficacy, and potency of V. H. reagents, plenty of heterocyclic compounds can be synthesized which serve as a constituent in various novel medications and acts as a bridge between biology and chemistry. These carboxylate moieties can effectively cooperate as precursors for several multi-component reactions (MCR) including Strecker synthesis, Bucherer-Berg reaction and post-MCR cyclization, modified variants with various pharmaceutical applications such as anti-tumor, anti-convulsant, anti-chitosomal and so on.

Comparative evaluation of fracture resistance among conventional versus herbal irrigants in root canal treated teeth: In vitro study

To evaluate the efficacy of conventional irrigants and herbal extracts materials which helps to resist fracture of endodontically treated teeth. 75 maxillary human permanent incisor teeth instrumented using ProTaper rotary files till apical size(F4). Instrumented samples divided into 5 groups with n = 15 based on various irrigants used. Group I: normal saline, Group II: 5% sodium hypochlorite (NaOCl), Group III: 2% chlorohexidine, Group IV: 10% Azadirachta indica (neem extract) and Group V: 10% Ocimum sanctum (tulsi extract).After that, root canals were proceeded to be filled by using single gutta-percha cone and Sealapex sealer. Specimens were then prepared and loaded until root fracture occurred. Maximum mean flexural strength of dentin (fracture resistance) was obtained from group treated with 2% chlorohexidine and 10% neem extract. Least fracture resistance was observed with 5% NaOCl. Herbal irrigants can be used as an alternative to NaOCl as they exhibit high fracture resistance.

Comparison of single and multiple file rotary endodontic instruments for debris and irrigant extrusion: An in vitro study

Aim

The aim of this study was to assess and compare the quantity of apically debris which was extruded apically by TruNatomy (TN), ProTaper Next (PTN), HyFlex electric discharge machining (EDM), and HyFlex controlled memory (CM), following root canal preparation.

Materials and Methods

Sixty extracted single-canal mandibular premolars were used. The root canal preparation was done with TN, HyFlex EDM, PTN, or HyFlex CM files. The preweight debris, which was extruded apically, was collected in the Eppendorf tube and later on incubated at 670°C for 3 days and weighed again to record the extruded debris.

Results

The result showed that there was a significant reduction in debris extrusion by TN system, followed by PTN system, HyFlex EDM, and maximum extrusion in HyFlex CM (P < 0.05). Between the PTN and TN groups as well as between the HyFlex EDM and HyFlex CM groups, statistically significant difference was not observed (P > 0.05).

Conclusion

Apical debris extrusion is the inherent nature of the all file systems. Nevertheless, the TN file system produced substantially minimum debris extrusion among other systems compared in the study.

Competency-based postgraduate training: Mentoring and monitoring using entrustable professional activities with descriptive rubrics for objectivity- A step beyond Dreyfus

Background At Sri Balaji Vidyapeeth, a competency-based learning and training (CoBaLT©) model for postgraduate (PG) curriculum, within the regulatory norms, was implemented in 2016 after adequate faculty development programmes. This focused on well-defined outcomes. Methods A review of the outcomes was undertaken in 2018 as part of internal quality assurance receiving feedback from all stakeholders, viz. students, alumni and faculty. Recent publications were also reviewed. A major problem identified was lack of clarity in definition of levels leading to subjectivity in assessment while grading. It was also noted that the process needed to be aligned with the programme outcomes. Further refinements were, therefore, made to align and objectivize formative assessment using entrustable professional activities (EPA) with the aid of descriptive rubrics of sub-competencies and milestones. Addition of detailed rubrics for objectivity takes assessment a step beyond the Dreyfus model, aligning overall to the programme outcomes. Results Achievement of appropriate grades in EPAs by individual candidates ensures entrustability in professional activities by the time of completion of the PG programme. The modification was found more transparent and objective with reference to grading by the teachers and more conducive to reflections by the residents on their performance and how to improve it. Conclusions The use of descriptive rubrics along with EPAs brings transparency and plays a key role as an objective assessment tool, which can lend direction to individual resident learning and entrustability. This is an important component of outcome-based education.

Physicochemical parameters for design and development of lead herbicide molecules: Is 'Lipinski's rule of 5' appropriate for herbicide discovery?

BACKGROUND

Herbicide use has been a great add-on in agriculture, aiding weed management in crop fields, thereby escalating crop production. However, the development of resistance in weeds against the existing herbicides is a setback. The development of herbicide resistance has compelled the agrochemical industries to replace existing herbicides with novel agrochemicals. Developing new herbicide molecules through traditional methods is time-consuming and cost-prohibitive. The use of high-throughput virtual screening (HTVS) through physicochemical properties, de novo design and combinatorial design of molecules with cutting-edge computational methods is an alternative to the traditional techniques in lead molecule discovery. The lack of optimal physicochemical criteria for screening herbicide-like molecules has become a hindrance in the process.

RESULTS

In this study, physicochemical parameters [molecular weight, aromatic atoms, rotatable bonds, hydrogen-bonding capacity, topological polar surface area (TPSA), polarity and solubility] of known herbicide molecules have been studied and evaluated, and optimal criteria have been proposed for target-specific herbicides. Properties including molecular weight and hydrogen (H)-bond acceptor atoms tend to have higher values, but the range of H-bond donor atoms is relatively lower. These are distinguishable characteristics in herbicides when compared with oral drugs. Significant variations in optimal physicochemical parameters between herbicides of different groups (targeting weeds with different modes of action) have been observed.

CONCLUSION

The proposed parameters for respective target sites could be used as filters for in silico screening, designing and developing of target-specific lead herbicide molecules. © 2023 Society of Chemical Industry.

Sequence and structural similarities of ACCase protein of Phalaris minor and wheat: An insight to explain herbicide selectivity

Uncontrolled growth of Phalaris minor in the wheat (Triticum aestivum) crop has remained a problem, leading to a massive reduction in wheat grain production. Herbicides have been used to control the weed, which leads to the development of frequent resistance in P. minor and mutant biotypes were also reported (Trp2027Cys and Ile2041Asn). Development of resistance enforced agro researchers to analyses the action of herbicide on P. minor. In this study, the sequence and structure of P. minor and T. aestivum Acetyl CoA Carboxylase (ACCase) have been analysed to locate the differences in their sequence and structure and to formulate a plausible explanation of the selectivity of herbicides which may help in the rationale discovery of noble herbicides. The sequence and 3D structure analysis of weed and wheat ACCase indicate minute differences in the distantly located amino acid residues. However, proteins are conserved at the binding site of herbicides with no mutation at the catalytic site. Analysis indicates that herbicides selectively target P. minor ACCase might be due to unknown other reasons, but not due to differences in their protein sequence and structure.

Flap sub-domain dynamics of serine-threonine phosphatase (Stp1) of Staphylococcus aureus: an accelerated molecular dynamics simulation study

Vancomycin and daptomycin are commonly used glycopeptide antibiotics to cure Gram-positive staphylococcal infections. The clinical isolates of mutant Staphylococcus aureus strains, Methicillin-Resistant (MRSA) and Vancomycin-Resistant (VRSA), have developed resistance against these antibiotics. A recently discovered Serine/threonine phosphatase (Stp1) is an Mn⁺² containing protein at the active site with a flap sub-domain that participates in the phospho-signaling system of bacterial cell wall formation. The flap sub-domain probably regulates substrates recruitment and release with an extra Mn⁺², possibly highly flexible as in the other homologous family of proteins. In this study, the flap sub-domain has been sampled with conventional and accelerated molecular dynamics (cMD and aMD) simulations to get other sub-optimal conformational states of the protein that are nearly impossible to observe through experimental methods. Trajectory analysis has shown that protein remained static in cMD while dynamic in aMD with RMSD of ∼2Å and ∼3Å, respectively. Accelerated MD has shown greater flexibility of ∼4 Å in the flap sub-domain, while cMD only captured a deviation of ∼ 2 Å. Later, the dynamic cross-correlation map (DCCM) confirmed that the flap sub-domain is significantly more flexible than the other part of the structure, indicating its role in substrate regulation. Secondary structure transition in the flap sub-domain, i.e. 3-10 helix and turn (PRO159 - ILE163) region of the flap sub-domain shifted into α-helix, which is a more stable structure. Further, the trajectory has been clustered, and conformational states extracted, which may be exploited in structure-based antibiotics discovery.

Correction: G82S RAGE polymorphism influences amyloid-RAGE interactions relevant in Alzheimer's disease pathology

[This corrects the article DOI: 10.1371/journal.pone.0225487.].

Clinicopathological profile of invasive ductal breast carcinoma in a government tertiary care center in eastern India

Introduction and Aim: There is an increasing incidence of breast cancer (BC) in our country. The study aimed to find out the demographic profile, clinical presentation, and management in patients treated for invasive ductal breast carcinoma (IDC) in a rural government teaching hospital and to study the association of sociodemographic factors with BC stage. Materials and Methods: The study retrospectively analyzed 100 IDC females treated at Midnapore medical college, West Bengal, India from January 2017 to December 2019. The study included female patients of all ages diagnosed with IDC who had undergone surgery. Male BC, bilateral BC, other pathological types of BC were excluded. Results: The mean age was 56.54±12.99 years. Sixty-seven cases were postmenopausal. Eighty-one cases were from rural areas. Seventy-three cases had education up to middle school. Eighty-six cases had a lower socioeconomic status. Ninety-eight cases had unilateral breast lump and only 2% had a nonpalpable breast lump. The left breast was more commonly involved. The mean tumour size was 4.33 cm. Ninety-eight cases underwent a modified radical mastectomy. Stage III was the most commonly observed BC and seen in 40 cases followed by stage II in 36 cases. Sixty-one cases had advanced BC. Liver metastasis was seen in 21cases. Sixty-nine cases had axillary node(ALN) positivity. Sixty-eight cases had lymphovascular emboli (LVE). High-grade tumour was seen in 77%. High-grade tumour was more common in young women. Seventy three cases of tumours were estrogen receptor-positive (ER+) while 66% progesterone receptor-positive (PR+). Eighteen cases were human epidermal growth factor 2 receptor-positive. Conclusion: High incidence of advanced BC is found in rural areas due to a lack of awareness and health infrastructure.

G82S RAGE polymorphism influences amyloid-RAGE interactions relevant in Alzheimer's disease pathology

Receptor for advanced glycation end products (RAGE) has been implicated in the pathophysiology of Alzheimers disease(AD) due to its ability to bind amyloid-beta (Aβ42) and mediate inflammatory response. G82S RAGE polymorphism is associated with AD but the molecular mechanism for this association is not understood. Our previous in silico study indicated a higher binding affinity for mutated G82S RAGE, which could be caused due to changes in N linked glycosylation at residue N81. To confirm this hypothesis, in the present study molecular dynamics (MD) simulations were used to simulate the wild type (WT) and G82S glycosylated structures of RAGE to identify the global structural changes and to find the binding efficiency with Aβ42 peptide. Binding pocket analysis of the MD trajectory showed that cavity/binding pocket in mutant G82S glycosylated RAGE variants is more exposed and accessible to external ligands compared to WT RAGE, which can enhance the affinity of RAGE for Aβ. To validate the above concept, an in vitro binding study was carried using SHSY5Y cell line expressing recombinant WT and mutated RAGE variant individually to which HiLyte Fluor labeled Aβ42 was incubated at different concentrations. Saturated binding kinetics method was adopted to determine the Kd values for Aβ42 binding to RAGE. The Kd value for Aβ42- WT and Aβ42-mutant RAGE binding were 92±40 nM (95% CI-52 to 152nM; R2-0.92) and 45±20 nM (95% CI -29 to 64nM; R2-0.93), respectively. The Kd value of <100nM observed for both variants implicates RAGE as a high-affinity receptor for Aβ42 and mutant RAGE has higher affinity compared to WT. The alteration in binding affinity is responsible for activation of the inflammatory pathway as implicated by enhanced expression of TNFα and IL6 in mutant RAGE expressing cell line which gives a mechanistic view for the G82S RAGE association with AD.

Breaking the stress with a non-rigid connector

Lone standing abutments or pier abutments have usually been restored with a conventional fixed partial denture (FPD) using a rigid connector between the pontics and the retainers. However, such fixed and rigid restorations have been associated with a higher rate of debonding, microleakage, caries, etc., The aim of the modern day prosthodontics is the preservation of what remains as given by M.M Devan. As a result, a non rigid connector (NRC) may be the connector of choice in situations of pier abutment. A NRC acts as a stress breaker so that the anterior and posterior segments can move independent of each other. This case report presents a simple method of rehabilitating a patient with a pier abutment in the upper right posterior region of the mouth. Rehabilitation was done by FPD with an inverted key-keyway type NRC. Follow up was done up to 11 months.

International Nosocomial Infection Control Consortium (INICC) report, data summary of 45 countries for 2012-2017: Device-associated module

BACKGROUND

We report the results of International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2012 to December 2017 in 523 intensive care units (ICUs) in 45 countries from Latin America, Europe, Eastern Mediterranean, Southeast Asia, and Western Pacific.

METHODS

During the 6-year study period, prospective data from 532,483 ICU patients hospitalized in 242 hospitals, for an aggregate of 2,197,304 patient days, were collected through the INICC Surveillance Online System (ISOS). The Centers for Disease Control and Prevention-National Healthcare Safety Network (CDC-NHSN) definitions for device-associated health care-associated infection (DA-HAI) were applied.

RESULTS

Although device use in INICC ICUs was similar to that reported from CDC-NHSN ICUs, DA-HAI rates were higher in the INICC ICUs: in the medical-surgical ICUs, the pooled central line-associated bloodstream infection rate was higher (5.05 vs 0.8 per 1,000 central line-days); the ventilator-associated pneumonia rate was also higher (14.1 vs 0.9 per 1,000 ventilator-days,), as well as the rate of catheter-associated urinary tract infection (5.1 vs 1.7 per 1,000 catheter-days). From blood cultures samples, frequencies of resistance, such as of Pseudomonas aeruginosa to piperacillin-tazobactam (33.0% vs 18.3%), were also higher.

CONCLUSIONS

Despite a significant trend toward the reduction in INICC ICUs, DA-HAI rates are still much higher compared with CDC-NHSN's ICUs representing the developed world. It is INICC's main goal to provide basic and cost-effective resources, through the INICC Surveillance Online System to tackle the burden of DA-HAIs effectively.

Acetamides: chemotherapeutic agents for inflammation-associated cancers

Now clear evidences are available to support the hypothesis that inflammation accelerates the conditions including events and molecules that reach to various types of cancers. Inflammation is a normal response to infection containing the innate and adaptive immune systems. However, when allowed to continue, unresolved, perturbation of cellular microenvironment takes place; therefore, it leads to adaptations in genes that are linked to cancer. In addition, a lot of data are accessible confirming the concept that tumour microenvironment is orchestrated by various inflammatory cells and goes to neoplastic process and finally invasion, migration and metastasis. However, infiltrations of leucocytes lead to angiogenesis, propagation and invasion. An inflammatory microenvironment that perhaps fostering impact of angiogenesis include cytokines, chemokines, enzymes and growth factors that play key role for expansion and invasion of cancer cells. This insight highlights the pathogenesis of inflammation-associated cancers and also touches and fosters the role of acetamides for the treatment and chemoprevention of carcinomas that are allied with inflammation.

Quality of Labor Epidural Analgesia and Maternal Outcome With Levobupivacaine and Ropivacaine: A Double-Blinded Randomized Trial

Background:

Quality of labor analgesia plays a vital role in the maternal outcome. Very few literature are available analyzing the quality of epidural labor analgesia.

Aim:

The aim of this study was to compare the effectiveness of 0.1% levobupivacaine and 0.1% ropivacaine with fentanyl as an adjuvant for epidural labor analgesia in terms of onset, duration, quality of analgesia, and degree of motor blockade.

Methodology:

Sixty nulliparous parturients, with singleton uncomplicated pregnancy, were recruited by continuous sampling. Parturients were randomized to receive either levobupivacaine 0.1% or ropivacaine 0.1% with 2 μg/ml fentanyl as an intermittent epidural bolus. The epidural analgesia was initiated with 12 ml of study drug solution in the active stage of labor (cervix 3 cm dilated). Demand bolus was given whenever the visual analog scale (VAS) score >3. Onset, duration, and quality of analgesia and degree of motor blockade were analyzed. Maternal outcome was evaluated in terms of mode of delivery, duration of labor, and assisted vaginal delivery.

Statistical Analysis:

All the data were recorded in Microsoft Office Excel. Statistical analysis was carried out using SPSS version 19.0 (IBM SPSS, USA) software with Regression Modules installed. Descriptive analyses were reported as mean and standard deviation of continuous variables.

Results:

The mean onset of analgesia was shorter in ropivacaine (21.43 ± 2 min) than in levobupivacaine group (23.57 ± 1.71 min) (P = 0.000). Duration of analgesia was shorter in ropivacaine (60 ± 14 min) than levobupivacaine (68 ± 11 min) (P = 0.027). Levobupivacaine produced a better quality of analgesia in terms of not perceiving pain and uterine contraction during labor analgesia but was associated with 37% incidence of instrumental delivery. Duration of labor and rate of cesarean section were comparable between the groups.

Conclusion:

Quality of analgesia in labor epidural was superior to levobupivacaine but was associated with higher incidence of instrumental vaginal delivery.

Antioxidant Potential of Lingzhi or Reishi Medicinal Mushroom, Ganoderma lucidum (Higher Basidiomycetes) Cultivated on Artocarpus heterophyllus Sawdust Substrate in India

The artificial cultivation of Ganoderma lucidum (MTCC1039) using Artocarpus heterophyllus as sawdust substrate was optimized and free radical scavenging activities of the generated fruiting bodies were investigated. The choice of A. heterophyllus as substrate was due to its easy availability in South India. Sawdust supplemented with dextrose medium yielded better spawn hyphae and early fruiting body initiation (15 days). The biological yield obtained was 42.06 ± 2.14 g/packet and the biological efficiency was 8.41 ± 0.48%. Both aqueous and methanolic extracts of fruiting body were analyzed for radical scavenging activity. Methanolic extract showed maximum scavenging activity for 1,1-diphenyl-2-picrylhydrazyl (IC50 = 290 μg/ml) and 2,2'-azino-bis(3-ethylbenzothiazoline- 6-sulphonic acid (IC50 = 580 μg/ml), whereas aqueous extract had better scavenging for ferric reducing antioxidant power (IC50 = 5 μg/ml). Total phenolic content and total antioxidant capacity were significantly higher in methanolic extract (p < 0.01). A positive correlation existed between the phenolic content and antioxidant activity. Our results indicated that fruiting bodies of G. lucidum cultivated in sawdust medium possess antioxidant property, which can be exploited for therapeutic application.

Rapid and reliable smooth extubation - Comparison of fentanyl with dexmedetomidine: A randomized, double-blind clinical trial

BACKGROUND

Fentanyl and dexmedetomidine have been tried to attenuate airway and circulatory reflexes during emergence and extubation individually but have not been compared with respect to the level of sedation to evolve a reliable technique for rapid and smooth extubation.

AIM

To compare the effects of fentanyl and dexmedetomidine in attenuating airway and circulatory reflexes during emergence and extubation of the endotracheal tube.

SETTING AND DESIGN

This double-blind, randomized, controlled study was done in patients undergoing surgery under general anesthesia belonging to the American Society of Anesthesiologists physical status 1 or 2.

METHODOLOGY

All patients received a standardized anesthetic protocol. Patients were randomized to receive either fentanyl 1 μg/kg or dexmedetomidine 0.75 μg/kg. Fifteen minutes before expected last surgical suture, isoflurane was cutoff and equal amount of test solution was given when train-of-four ratio was 0.3. The degree of sedation, airway, and circulatory responses at the time of suction and extubation were analyzed.

STATISTICAL ANALYSIS USED

Chi-square test for nonparametric data and t-test for parametric data.

RESULTS

Heart rate (HR) was comparable in both the groups until endotracheal extubation. Later, there was rise in HR in fentanyl group. There was stastisticaly significant drop in blood pressure at 5 min after test drug administration in both the groups. Airway response for suctioning and extubation was better in dexmedetomidine group and it was associated with better sedation score than fentanyl group.

CONCLUSION

Single dose of 0.75 μg/kg dexmedetomidine given 15 min before extubation provides smooth extubation when compared to fentanyl.

A systematic review and meta-analysis of plasma amyloid 1-42 and tau as biomarkers for Alzheimer's disease

OBJECTIVE

Amyloid 1-42 (Aβ42) and tau in cerebrospinal fluid are currently used as markers for diagnosis of Alzheimer's disease. Conflicting reports exist regarding their plasma levels in Alzheimer's disease patients. A meta-analysis was performed to statistically validate the use of plasma Aβ42 and tau as biomarkers for Alzheimer's disease.

METHODS

Different databases were searched using the search key: (amyloid OR amyloid1-42 OR Aβ42) AND (tau OR total tau) AND plasma AND (alzheimer's OR alzheimer's disease), and for databases not accepting boolean search, records were retrieved using the search key: plasma + amyloid + tau + alzheimer's. A total of 1880 articles for Aβ42 and 1508 articles for tau were shortlisted. The abstracts were screened, and 69 articles reporting plasma Aβ42 levels and 6 articles reporting plasma tau were identified. After exclusion, 25 studies reporting plasma Aβ42 and 6 studies reporting total tau were analysed in Review Manager version 5.2 using weighted mean difference method, and the bias between studies was assessed using the funnel plot.

RESULTS

Plasma Aβ42 and tau did not vary significantly between Alzheimer's disease patients and controls. The funnel plot showed that there was no bias between studies for Aβ42, while possible bias existed for tau due to availability of limited studies.

CONCLUSION

This analysis pinpoints that plasma Aβ42 and tau could not serve as reliable markers independently for diagnosis of Alzheimer's disease and a cohort study with age, sex and apolipoprotein E correction is warranted for their possible use as Alzheimer's disease markers.

Anticancer, anti-inflammatory, and analgesic activities of synthesized 2-(substituted phenoxy) acetamide derivatives

The aphorism was to develop new chemical entities as potential anticancer, anti-inflammatory, and analgesic agents. The Leuckart synthetic pathway was utilized in development of novel series of 2-(substituted phenoxy)-N-(1-phenylethyl)acetamide derivatives. The compounds containing 1-phenylethylamine as basic moiety attached to substituted phenols were assessed for their anticancer activity against MCF-7 (breast cancer), SK-N-SH (neuroblastoma), anti-inflammatory activity, and analgesic activity. These investigations revealed that synthesized products 3a-j with halogens on the aromatic ring favors as the anticancer and anti-inflammatory activity. Among all, compound 3c N-(1-(4-chlorophenyl)ethyl)-2-(4-nitrophenoxy)acetamide exhibited anticancer, anti-inflammatory, and analgesic activities. In conclusion, 3c may have potential to be developed into a therapeutic agent.

Comparison of morphine and fentanyl in attenuation of Intra operative stress response under general anesthesia: A randomized double blinded study

Background: This randomized double blinded study was done to compare the effect of intravenous morphine and fentanyl in attenuation of stress response during surgeries under general anesthesia in adults. The attenuation of stress response was analyzed with changes in serum cortisol and glucose levels one hour after induction of anesthesia. Methods: Fifty consented healthy volunteers in age group 20-50, under ASA I and ASA II posted for elective surgery were included in the study. Two groups of 25 each, group M who received 0.2 mg/kg body weight of morphine and group F who received 2 microgram/kg body weight of fentanyl before anaesthetic induction were compared. The members of two groups were randomly allocated and double blinded using sealed envelope technique. Blood samples were collected for baseline glucose and cortisol in all the subjects. One hour after the administration of study drugs, which was given at the time of induction blood samples were collected for analysis of glucose and cortisol. The changes in blood glucose and serum cortisol levels were compared at the end of the study using independent samples ‘t’ test. Results: There was no significant difference in blood sugar levels in both groups at the end of 1 hour. But there was significant increase in serum cortisol levels in group F compared to group M. Conclusion: This study concludes that morphine is better than fentanyl in attenuation of Intraoperative stress by effectively controlling serum cortisol levels. DOI: http://dx.doi.org/10.3126/ajms.v5i4.9796 Asian Journal of Medical Sciences 2014 Vol.5(4); 65-68

Evaluation of selenium, redox status and their association with plasma amyloid/tau in Alzheimer's disease

The aim of the study was to evaluate blood selenium and antioxidants as possible oxidative stress markers in Alzheimer's disease (AD) along with amyloid β42 (Aβ42) and tau by comparing them with vascular dementia (VD) and age-matched healthy controls. Selenium, total tau, Aβ42, glutathione (GSH) and malondialdehyde (MDA) levels and the activities of antioxidant enzymes were analysed in the blood of AD patients (n = 30), VD patients (n = 35) and controls (n = 40) from South India. Plasma Aβ42 level was significantly higher (P < 0.001) in both AD and VD compared to controls. Total tau and tau-to-amyloid ratio were significantly lower in both AD and VD (P < 0.001), compared to controls, and a significant difference (P < 0.01 and P < 0.05, respectively) was also observed between AD and VD. The receiver operating characteristic (ROC) curve-derived cutoff values of <3.5 for tau-to-Aβ42 ratio and <520 pg/ml for total tau showed sensitivity and specificity of around 67-72 % for differentiating AD from VD and around 90 % for AD from controls, indicating that they could serve as reliable AD-specific markers. The MDA levels were significantly higher (P < 0.001) in both dementia groups along with a significant decrease (P < 0.001) in reduced GSH levels, indicating elevated oxidative stress and altered redox status in both forms of dementia. Selenium levels did not vary significantly between the three groups. The activity of glutathione peroxidase increased in both AD and VD compared to controls, with a concomitant decrease in glutathione reductase and glucose-6-phospate dehydrogenase (P < 0.001) activity. The activity of thioredoxin reductase was significantly lower in both patient groups (P < 0.001) compared to healthy controls. No correlation was observed between selenium and activities of selenoenzymes, tau, Aβ42 or tau-to-Aβ42 ratio, when analysing independently, indicating that blood selenium may not be directly involved in Aβ production and in regulating tau/Aβ42-mediated mechanism in AD. The present study emphasizes the enhanced oxidative stress in AD pathology and plasma tau and tau-to-amyloid ratio as possible markers to differentiate AD from VD. The study also points that blood selenium may not be involved in regulating oxidative stress in AD, and a longitudinal study correlating plasma and cerebrospinal fluid (CSF) selenium and selenoprotein levels is warranted.

Experimental and theoretical studies of vibrational spectrum and molecular structure and related properties of pyridoxine (vitamin B6)

Vibrational spectrum of pyridoxine has been investigated using experimental IR and Raman spectroscopic and density functional theory (DFT) methods. Vibrational assignments of the observed IR and Raman bands have been proposed in light of the results obtained from computations. In order to assign the observed IR and Raman frequencies the potential energy distributions (PEDs) have also been computed. Optimized geometrical parameters suggest that if the OH groups of the two methyl groups are replaced by H atoms the resulting molecule has Cs point group symmetry. To investigate molecular stability and bond strength we have used natural bond orbital analysis (NBO). Charge transfer occurs in the molecule have been shown by the calculated highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) energies. The mapping of electron density iso-surface with electrostatic potential (ESP), has been carried out to get the information about the size, shape, charge density distribution and site of chemical reactivity of the molecule.

Ab initio determination of geometries and vibrational characteristics of building blocks of organic super-conductors: TTF and its derivatives

Molecular behavior of the building block {[2-(1,3-dithiole-2-ylidene)-1,3-dithiole] ≡ tetrathiafulvalene (TTF)} of organic superconductors have been investigated along with its three derivatives, namely, {[2-(1,3-dioxole-2-ylidene)-1,3-dioxole] ≡ tetraoxafulvalene (TOF)}; [2,2]-bi -[[1,3] oxathiolylidene] ≡ Der I and 2-(3H-Furan-2-ylidene)-[1,3] oxathiole ≡ Der II. The properties of the molecules such as molecular geometries, frontier MOs and vibrational spectra have been investigated by using DFT method at the B3LYP level employing 6-311++G(d,p) basis set. The geometrical parameters and atomic charges on various atomic sites of the TTF, TOF, Ders I and II suggest extended conjugation in these systems. The present calculations lead to the reassignments for of some of the fundamentals and new interpretations for some of the observed IR and Raman frequencies. One of the two modes involved in the Fermi resonance giving rise to the doublet 1555 and 1564 cm(-1) needed to be revised and another doublet 3083 and 3108 cm(-1) could be interpreted as a Fermi resonance doublet. Out of the two ν(C = C) modes under the a(1) species, the lower frequency mode is assigned to the ν(C = C) of the ring and the higher one to the ν(C = C) of the central C = C bond contrary to the assignment reported in literature. The conducting properties of these molecules depend mainly on this mode.

Experimental IR and Raman spectra and quantum chemical studies of molecular structures, conformers and vibrational characteristics of L-ascorbic acid and its anion and cation

IR and spectra of the L-ascorbic acid (L-AA) also known as vitamin C have been recorded in the region 4000-50 cm(-1). In order to make vibrational assignments of the observed IR and Raman bands computations were carried out by employing the RHF and DFT methods to calculate the molecular geometries and harmonic vibrational frequencies along with other related parameters for the neutral L-AA and its singly charged anionic (L-AA(-)) and cationic (L-AA(+)) species. Significant changes have been found for different characteristics of a number of vibrational modes. The four ν(O-H) modes of the L-AA molecule are found in the order ν(O(9)-H(10))>ν(O(19)-H(20))>ν(O(7)-H(8))>ν(O(14)-H(15)) which could be due to complexity of hydrogen bonding in the lactone ring and the side chain. The CO stretching wavenumber (ν(46)) decreases by 151 cm(-1) in going from the neutral to the anionic species whereas it increases by 151 cm(-1) in going from the anionic to the cationic species. The anionic radicals have less kinetic stabilities and high chemical reactivity as compared to the neutral molecule. It is found that the cationic radical of L-AA is kinetically least stable and chemically most reactive as compared to its neutral and anionic species.

Comparison of digital radiography and apex locator with the conventional method in root length determination of primary teeth

AIM

The purpose of this study was to compare the Working length in primary teeth endodontics using intra oral digital radiovisiography and apex locator with conventional method for accuracy.

MATERIALS AND METHODS

This in vivo study was conducted on 30 primary teeth which were indicated for pulpectomy in the patients of the age group of 5-11 years All experimental teeth had adequate remaining tooth structure for rubber dam isolation and radiographicaly visible canals. Endodontic treatment was required due to irreversible pulpitis or pulp necrosis. A standardized intraoral periapical radiograph of the tooth was taken using conventional method by paralleling technique. The distance between the source and the tooth, tooth and the films were standardized using X-ray positioning device. During the pulpectomy procedure, the working length was determined by digital radiograph and apex locator. The measurements were then compared with the conventional method of root canal measurement technique for accuracy.

RESULT

From the results obtained we can conclude that Working length determined in primary molars using digital radiography and Apex locator did not show any significant difference in the mean working length measurements when compared with the conventional radiographic method.

CONCLUSIONS

Apex locator is comparable to conventional radiograph in determining the working length without radiation in the primary teeth. Intraoral digital radiography is the safest method in determining the working length with significant reduction in radiation exposure.Hence, both the techniques can be safely used as alternatives to conventional radiographic methods in determining working length in primary teeth.

Free radicals and antioxidant status in acute myocardial infarction patients with and without diabetes mellitus

In this study we investigated the oxidative stress, antioxidants and inflammatory molecules in patients of acute myocardial infarction (AMI) with diabetes (n=50) and non-diabetes (n=50). Fifty healthy subjects were taken as control. The levels of plasma TBARS and ceruloplasmin levels were significantly high in diabetic and non-diabetic AMI patients as compared with control. On the other hand, the activities of both enzymatic and non-enzymatic antioxidants were significantly decreased in diabetic and non-diabetic AMI patients as compared with control. Inflammatory markers showed significant rise in diabetic patients as compared with controls. Our results show increased inflammation and oxidative stress in patients with AMI, and magnitude of imbalance is greater in diabetic AMI patients, possibly because of greater inflammation in diabetic patients.Keywords: Acute myocardial infarction; Antioxidant; Free radical; Diabetes mellitusOnline: 8 Feb 2010DOI: http://dx.doi.org/10.3329/bmrcb.v35i3.2999Bangladesh Med Res Counc Bull 2009; 35: 95-100    

Circulating lipid peroxidation, plasma and erythrocyte antioxidant status in patients with rheumatoid arthritis

The aim of the study was to investigate the levels of lipid peroxidation, and both plasma and erythrocyte antioxidant states in patients with rheumatoid arthritis. The population consisted of 60 subjects divided into two groups, 30 subjects had evidence of rheumatoid arthritis and age and sex matched healthy subjects were studied as controls. The level of plasma and erythrocyte thiobarbituric acid reactive substances (TBARS) was markedly increased in both the rheumatoid arthritis patients when compared to control subjects. The activities of plasma and erythrocyte antioxidants were significantly decreased in rheumatoid arthritis. C reactive protein, rheumatoid factor and antistreptolysin-O were significantly higher in rheumatoid arthritis patients than in healthy subjects. In conclusion, on the basis of enhanced lipid peroxidation in rheumatoid arthritis patients with concomitant failure of both the plasma, and erythrocyte antioxidants defense mechanism. These results are consistent with the underlying hypothesis that there is an  imbalance between reactive oxygen species production and the antioxidant defense system in inflammatory rheumatoid arthritis disease.Keywords: Antioxidant; Lipid peroxidation; Rheumatoid arthritisOnline: 13 August 2009DOI: 10.3329/bmrcb.v35i2.2798Bangladesh Med Res Counc Bull 2009; 35: 57-62

Evaluation of antioxidant properties of berries

The present paper focuses on assessing the levels of various enzymatic and non-enzymatic antioxidants in selected berries of Indian sub-continent viz., gooseberry, grapes, orange and tomato. This study has revealed that orange, tomato and grapes possess predominant quantities of enzymatic antioxidants namely SOD, catalase and glutathione peroxidase respectively. The levels of antioxidants analyzed namely reduced glutathione, vitamin C and vitamin A were maximal in grapes, orange and tomato respectively. All the extracts of berries included in the present study inhibited iron inducedin vitro lipid peroxidation in erythrocytes, the extend of inhibition being highest for gooseberry and orange compared to tomato and grapes which could be attributed to their in-built antioxidant system.

Enzymatic and non-enzymatic antioxidants in selected Piper species

Piper species, commonly used in diet and traditional medicine were assessed for their antioxidant potential. Catalase activity was predominated in Piper longum, followed by Piper cubeba, green pepper, Piper brachystachyum and Piper nigrum. P. nigrum was richest in glutathione peroxidase and glucose-6-phosphate dehydrogenase, green pepper was richest in peroxidase and vitamin C while vitamin E was more in P. longum and P. nigrum. P. brachystachyum and P. longum were rich sources of vitamin A. All the Piper species had GSH content of around 1 to 2 nM/g tissue. The antioxidant components of Piper species constitute a very efficient system in scavenging a wide variety of reactive oxygen species. Antioxidant potential of Piper species was further confirmed by their ability to curtail in vitro lipid peroxidation by around 30-50% with concomitant increase in GSH content.

Structural and thermodynamic consequences of introducing alpha-aminoisobutyric acid in the S peptide of ribonuclease S

The S protein-S peptide interaction is a model system to study binding thermodynamics in proteins. We substituted alanine at position 4 in S peptide by alpha-aminoisobutyric acid (Aib) to investigate the effect of this substitution on the conformation of free S peptide and on its binding to S protein. The thermodynamic consequences of this replacement were studied using isothermal titration calorimetry. The structures of the free and complexed peptides were studied using circular dichroic spectroscopy and X-ray crystallography, respectively. The alanine4Aib replacement stabilizes the free S peptide helix and does not perturb the tertiary structure of RNase S. Surprisingly, and in contrast to the wild-type S peptide, the DeltaG degrees of binding of peptide to S pro, over the temperature range 5-30 degrees C, is virtually independent of temperature. At 25 degrees C, the DeltaDeltaG degrees, DeltaDeltaH degrees, DeltaDeltaS and DeltaDeltaCp of binding are 0.7 kcal/mol, 2.8 kcal/mol, 6 kcal/mol x K and -60 kcal/mol x K, respectively. The positive value of DeltaDeltaS is probably due to a decrease in the entropy of uncomplexed alanine4Aib relative to the wild-type peptide. The positive value of DeltaDeltaH: degrees is unexpected and is probably due to favorable interactions formed in uncomplexed alanine4Aib. This study addresses the thermodynamic and structural consequences of a replacement of alanine by Aib both in the unfolded and complexed states in proteins.

Risk factors for cervical dysplasia in Kerala, India

A study in Kerala, India, confirmed the importance of genital hygiene in the fight against infections that have a role in the development of cervical dysplasia and cancer. Many women cannot afford sanitary pads, while adequate facilities for washing after coitus are often unavailable. Health education, satisfactory living standards, and the empowerment of women are prerequisites for reducing the incidence of cervical dysplasia.

Evidence for altered structure and impaired mitochondrial electron transport function in selenium deficiency

Selenium (Se) deficiency in the experimental models, Coturnix coturnix japonica and Corcyra cephalonica, resulted in impaired mitochondrial substrate oxidations and lowered thiol levels. Studies with respiratory inhibitors confirmed reduced mitochondrial electron transport enzyme activities, especially at cytochrome c oxidase (COX), the terminal segment. Enhanced mitochondrial lipid peroxidation in Se deficiency was more pronounced in the heart tissue of the quail compared to other tissues. Glutathione peroxidase (GSH-Px) activity toward H2O2 and cumene hydroperoxide were generally low in the insect muscle tissue and activity toward H2O2 was maximal in the quail heart mitochondria that was not very sensitive to Se status. Lowered COX activity in Se deficiency was more directly correlated with the increased level of lipid peroxidation than with the GSH-Px activity measured, suggestive of Se mediated protective mechanisms independent of GSH-Px. Electron microscopic observations revealed structural changes such as loss of cristae with proliferative and degenerative changes of the mitochondria in Se deficiency. Involvement of Se in maintaining structure and functional efficiency of mitochondria is evident from the present study.

Mitochondrial selenium-75 uptake and regulation revealed by kinetic analysis

Uptake of Na2(75)SeO3 by mitochondria of the larvae of the insect C. cephalonica reared at different dietary selenium (Se) levels revealed: 1. A proportional increase in the uptake with externally added Na2(75)SeO3 in concentrations upto 25.32 microM; and 2. At each added selenite concentration, an increase up to 60 min, with linearity up to 15-30 min. A differential affinity for Na2(75)SeO3 was elicited in the mitochondrial protein fractions of different dietary Se groups and correlated well with the pattern and the ratio of distribution of incorporated 75Se in protein to nonprotein fractions. Kinetic studies on 75Se uptake by whole mitochondria negated passive diffusion of selenite and revealed a trend of negative cooperativity, confirmed by Hill and Scatchard plots. Half saturation value was estimated to be approx 13 nmole Se/mg mitochondrial protein. Scatchard plot for 75Se uptake was biphasic and the high affinity binding sites were estimated to be around 5 nmole/mg mitochondrial protein. Calculated dissociation constants revealed maximal affinity for 75Se in the 1.5 ppm group (KSe 0.0034 nM) and minimal in the basal group (KSe 0.007 nM). In the mitochondria of all the three dietary Se groups, the estimated low affinity sites amounted to be 15-19 nmole/mg mitochondrial protein. Inherent Se in the mitochondria of the high Se group positively enhanced the incorporation of 75Se in the mitochondrial protein fraction. About 20-30% of the total uptake was indicated to be energy linked as revealed by studies with respiratory inhibitors. Addition of sulfite and sulfate (5-25 microM) in the medium, inhibited 75Se uptake by 35-55%, suggestive of the involvement of the dicarboxylate port. Thiol interactive 75Se uptake was confirmed by the inhibition mediated by mersalyl and NEM up to 50-70%. The study revealed thiol-selenite interactions of metabolic significance during selenite uptake.

Metabolic relevance of selenium in the insect Corcyra cephalonica. Uptake of 75Se and subcellular distribution

Requirement, uptake, and subcellular distribution of Na2(75)SeO3 in the larvae of the insect C. cephalonica was investigated. That Se is well tolerated by C. cephalonica upto an added level of 2 ppm in the diet is suggested by the observed increase in body weight, total protein, and succinate dehydrogenase levels. Significant increases in the State 3 respiration ensued with Se supplementation up to 2 ppm in the mitochondrial oxidation of D-glycerol 1-phosphate, succinate and NADH, along with concomitant unaltered State 4 respiration, leading to enhanced RCR values. Maximal uptake of 75Se was registered in the larvae maintained on basal diet when subjected to short-term exposure to 0.5 ppm 75Se level. When exposure level was further increased up to 20 ppm, the observed decrease in the uptake of 75Se suggested that Se status of larvae itself controlled the tissue uptake. Subcellular distribution pattern revealed maximal incorporation of 75Se (cpm/g tissue) in the supernatant fraction, whereas, maximal specific 75Se activity (cpm/mg protein) was associated with the mitochondrial fraction. Autoradiography of the soluble fractions indicated the presence of single selenoprotein in the larval group with short term 2 ppm 75Se exposure. Inherent Se controls both the extent and the nature of distribution of mitochondrial 75Se incorporation. Uptake of 45Ca by the insect mitochondria was enhanced by dietary Se up to 2 ppm but was unaffected by addition of in vitro 75Se in the medium. A more fundamental role for Se in the mitochondrial energy metabolism emerges from these studies.

In vivo unwinding fluorimetric assay as evidence of the damage induced by fenarimol and DNOC in rat liver DNA

Five pesticides [amitraz, cyanazine, cyhexatin, dinitro-o-cresol (DNOC), and fenarimol] were tested as pure active ingredients for in vivo induction of DNA strand breaks on rat hepatocytes after intraperitoneal (ip) treatment. Two pesticides, fenarimol and DNOC, were capable of inducing DNA damage because they significantly increased the DNA unwinding rate. On the contrary, amitraz, cyanazine, and cyhexatin were not DNA-damaging agents.

Mitoxantrone, 5-fluorouracil and cyclophosphamide in advanced breast cancer

Thirty patients with advanced breast cancer, not pretreated with chemotherapy, received a polychemotherapy regimen containing mitoxantrone, fluorouracil and cyclophosphamide at the dose of 10 mg/m2, 500 mg/m2 and 500 mg/m2 i.v. respectively every 28 days. Out of 25 patients evaluable for response 9 patients achieved a partial remission (36%) for a median duration of 20.5 weeks. The main side effects were leukopenia (grade 3-4 in 70%) and nausea-vomiting (grade 3-4 in 27%). Alopecia was present only in 5 patients (17%). Three patients demonstrated instrumental signs of cardiotoxicity without clinical symptoms.