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1.
Cureus ; 16(6): e61497, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38952590

RESUMO

Background Periodontal disease poses a significant oral health challenge, involving inflammatory conditions impacting tooth-supporting structures. Treponema denticola, a "red complex" organism, plays a crucial role in periodontal pathogenesis, forming biofilms in subgingival environments and contributing to dysbiosis. Antimicrobial therapy is pivotal in managing periodontal disease, requiring a nuanced understanding of susceptibility patterns exhibited by key pathogens like T. denticola. Aims and objectives This study aims to investigate the antimicrobial susceptibility and resistance profiles of Treponema denticola, a prominent bacterium in periodontal disease, by examining its responses to various antimicrobial agents commonly used in periodontal therapy. Methodology Plaque samples were meticulously collected from individuals diagnosed with periodontal disease to ensure a diverse representation of the oral microbiome. All the samples were cultured, and red complex bacteria were isolated under anaerobic culture. Treponema denticola isolates were cultured from these samples under anaerobic conditions, and molecular techniques were employed for species identification. A comprehensive panel of antimicrobial agents was selected to assess the response of Treponema denticola. In vitro antimicrobial susceptibility testing (AST) was conducted using the antimicrobial gradient method, employing a hybrid approach combining elements of disk-diffusion and dilution methods. Results Treponema denticola had exhibited resistance to metronidazole, a commonly used antibiotic effective against anaerobic bacteria, emphasizing limitations in its applicability. However, the bacterium displayed sensitivity to tetracycline, imipenem, cefoperazone, chloramphenicol, clindamycin, and moxifloxacin, offering diverse therapeutic options. The antimicrobial gradient strip test provided detailed minimum inhibitory concentration (MIC) values, contributing to a nuanced understanding of susceptibility and resistance patterns. Conclusion This study significantly advances our understanding of Treponema denticola's antimicrobial susceptibility and resistance profiles in the context of periodontal disease. The findings underscore the importance of tailored treatment strategies and contribute to broader efforts in antimicrobial stewardship, aligning with global initiatives to combat antibiotic resistance. This research lays the foundation for more effective and personalized approaches to periodontal care, emphasizing the intricate microbial dynamics associated with periodontal health and disease.

2.
Cureus ; 16(5): e61008, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38910778

RESUMO

Background Periodontitis, characterized by chronic inflammation and tissue destruction, remains a significant public health concern. Conventional treatment like scaling and root planing (SRP) is effective but often augmented with adjunctive therapies to improve outcomes. Local drug delivery (LDD) systems containing pharmacological agents offer targeted treatment with reduced systemic side effects. Rosuvastatin (RSV), known for its anti-inflammatory and tissue regenerative properties, has shown promise in periodontal therapy. This prospective clinical trial assessed the effectiveness of 1.2% RSV hydrogel as an adjunct to SRP in managing generalized chronic periodontitis. Methods Thirty patients were grouped into Group A (SRP alone) and Group B (SRP + 1.2% RSV hydrogel). Clinical measurements, such as the modified sulcular bleeding index (mSBI), probing pocket depth (PPD), and clinical attachment level (CAL), were documented both at the beginning of the study and after three months. Statistical analysis was performed using SPSS software. A p-value of less than 0.05 was considered statistically significant. Results Participants in Group B showed significant improvements in mSBI (from 2.34 ± 0.59 to 1.01 ± 0.29), PPD (from 7.36 ± 1.12 mm to 4.63 ± 0.88 mm), and CAL (from 8.56 ± 1.22 mm to 5.90 ± 1.24 mm) compared to Group A at the three-month follow-up. The mean values of these parameters decreased significantly in both groups from baseline to three months. However, the reductions were more substantial in Group B, indicating the beneficial effect of RSV hydrogel adjunctive therapy. Conclusion The study demonstrates the efficacy of 1.2% RSV hydrogel employed as a localized drug in enhancing the outcomes of SRP for generalized chronic periodontitis. The adjunctive use of RSV hydrogel led to noteworthy enhancements in clinical parameters, highlighting its potential in periodontal therapy.

3.
J Org Chem ; 89(10): 6838-6846, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38700910

RESUMO

Understanding the reaction mechanism and origin of regioselectivity in transition metal-catalyzed C-H activation/annulation reactions with 1,3-diynes has remained an intriguing challenge. In this article, to establish the mechanism and decipher the origin of regioselectivity, we report a detailed computational density functional theory-based mechanistic investigation on the recently developed Ru(II)-catalyzed [4 + 2] annulation of N-chlorobenzamides with 1,3-diynes for the synthesis of 3-alkynylated isoquinolone derivatives. Our calculations reveal a redox-neutral pathway for the annulation reaction. The stepwise analysis of the reaction channels indicates the migratory insertion step and the concerted reductive elimination/oxidative addition of the Ru(p-cymene) moiety to form the N-C bond leading to the 3-alkynylated product to be the selectivity- and rate-determining steps, respectively. Finally, the distortion/interaction analysis using the activation-strain model suggests the steric effect as the determining factor for the observed regioselectivity for the formation of the 3-alkynylated product. Overall, the computationally obtained key insights into the catalytic mechanism and the origin of regioselectivity in the C-H activation/annulation reaction can be used as a guide to rationally design and develop novel transformation strategies for heterocycle synthesis.

4.
Hematol., Transfus. Cell Ther. (Impr.) ; 45(4): 456-460, Oct.-Dec. 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1528643

RESUMO

ABSTRACT Introduction: Approximately 55.52% of the Indian population had been fully vaccinated by Jan. 2022, since its first roll out on January 16, 2021. A few concerns were raised concerning the Covishield vaccination related to thrombotic thrombocytopenia. Apheresis-derived platelet concentrates are frequently required in a plethora of clinical situations and post-vaccination decrement of platelet counts might lead to increased deferral of the plateletpheresis donors. Objectives. The aim of the study was to discover the effect of the Covishield vaccination on deferral rates of plateletpheresis donors. Methods: Blood samples were collected from the potential platelet donors for the completion of the standard questionnaire for the complete blood count. The data collected were tabulated in the MS Excel spreadsheet and the biostatistical analysis was performed with the SPSS v23. A p-value of < 0.05 was taken as significant. We compared this data with age-and sex-matched controls. Results: The mean age of cases and controls was 29.69 ± 8.57 and 30.15 ± 7.11, respectively. There was a significant difference in platelet counts of cases (188496.35 ± 72065.66/cumm) and controls (269524.50 ± 53981.60/cumm). Furthermore, donors who received one dose had higher platelet counts of 248676.47 ± 80075.24/cumm than those who received both doses of vaccine (179970.83 ± 66773.73/cumm). The difference in deferral rates between the two groups was remarkable (34.7% vs. 0.9%, with the p-value < 0.001). Conclusion: Vaccination certainly increased the deferral rates of plateletpheresis donors due to low platelet counts. Average platelet counts were low in fully vaccinated individuals, however, the platelets returned to normal counts as the post-vaccination days progressed.

5.
Org Biomol Chem ; 21(44): 8794-8812, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37901918

RESUMO

Modern times have witnessed an uprise in the synthesis and derivatization of nitrogen-containing fused heterocycles. Amination reactions involving nitrene chemistry have always been the most convenient choice for the incorporation of a nitrogen atom in a molecule. The utilization of an open nitrene species harnesses harsh conditions. Hence, transition metal-catalyzed C-H amination reactions using aminating agents have been an attractive choice. Electrophilic aminating agents for C-H amination reactions are well exploited due to their desirable reaction conditions. Out of all, anthranils have paved the way forward due to their utility in simultaneously forming two new functional groups (amine and carbonyl). Amination using anthranils follows a metal-nitrenoid pathway. Often, the amination has been followed by a Lewis acid or transition metal-mediated intramolecular cyclization to directly produce fused heterocycles. This review broadly demonstrates the utilization of anthranils as an aminating agent for transition metal-catalyzed C-H amination reactions. The focus has been given to the scope, limitations, and mechanistic understanding of using such an electrophilic aminating agent, anthranil, with transition metals.

6.
Org Lett ; 25(43): 7878-7883, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37871162

RESUMO

We have developed a Cp*Co(III)-catalyzed reverse regioselective [4 + 2] annulation of N-chlorobenzamides/acrylamides with vinylsilanes for the synthesis of 4-silylated isoquinolones. The reaction was performed at ambient temperature under redox-neutral conditions. The reaction utilized the N-Cl bond as an internal oxidant, furnished the required products with excellent regioselectivities, and demonstrated high functional group tolerance. The synthetic utility of 4-silylated isoquinolones has been demonstrated for the preparation of 4-heteroarylated and 4-alkylated isoquinolones via metal-free C-C couplings. Additionally, 3,4-dihydroisoquinolones were synthesized via protodesilylation of 4-silylated isoquinolones, thus making vinylsilane an ethylene surrogate.

7.
ACS Omega ; 8(28): 25262-25271, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37483194

RESUMO

We have developed Cp*Co(III)-catalyzed redox-neutral synthesis of 3,4-unsubstituted isoquinoline 1(2H)-ones at ambient temperature using N-chloroamides as a starting material. The reaction utilizes vinyl acetate as an inexpensive and benign acetylene surrogate. The N-Cl bond of the N-chlorobenzamides plays the role of an internal oxidant and hence precludes the need for an external oxidant. The reaction works with a wide range of substrates having various functional groups and a substrate containing a heterocyclic ring. Notably, the reaction is extended to the N-chloroacrylamides in which vinylic C-H activation occurs to furnish the 2-pyridone derivatives. Preliminary mechanistic studies were also conducted to shed light on the mechanism of this reaction.

8.
Org Biomol Chem ; 21(19): 3918-3941, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37128760

RESUMO

A variety of biologically active molecules, pharmaceuticals, and natural products consist of a nitrogen-containing heterocyclic backbone. The majority of them are isoquinolones, indoles, isoquinolines, etc.; thereby the synthesis and derivatization of such heterocycles are synthetically very relevant. Also, certain naphthol derivatives have high synthetic utility as agrochemicals and in dye industries. Previous approaches have utilized ruthenium, rhodium, or iridium which may not be desirable due to the high toxicity, low abundance, and high cost of such 4d and 5d metals. Moreover, the need for an external oxidant during the reaction also adds by-products to the system. A high-valent cobalt-catalyzed redox-neutral C-H functionalization strategy has emerged to be a far better alternative in this regard. The use of the non-noble metal cobalt allows for selectivity and specificity in product formation. Also, the redox-neutral concept avoids the use of an external oxidant either due to the presence of a metal in a non-variable oxidation state throughout the catalytic cycle or due to the presence of an oxidizing directing group or an oxidizing coupling partner. Such an oxidizing directing group not only directs the catalyst to a specific reaction site by chelation but also regenerates the catalyst at the end of the cycle. Certain bonds such as N-O, N-N, N-Cl, N-S, and C-S are the main game-players behind the oxidizing property of such directing groups. In the other case, the directing group only chelates the catalyst to a reaction center, whereas the oxidation is carried out by the upcoming group/coupling partner. Overall, merging the redox-neutral concept with the high-valent cobalt catalysis is paving the way forward toward a sustainable and environmentally friendly approach. This review critically describes the mechanistic understanding, scope, limitations, and synthesis of various biologically relevant heterocycles via the redox-neutral concept in the high-valent Cp*Co(III)-catalyzed C-H functionalization chemistry domain.

9.
Med J Armed Forces India ; 79(3): 280-285, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37193527

RESUMO

Background: Obstetrics as a speciality has a very long association with the transfusion services and poses its own set of immunohematological (IHL) challenges. A study was carried out to evaluate the spectrum of IHL issues in obstetrics in our setup and to suggest a way forward. Methods: This study was carried out in a transfusion services setup catering to antenatal care (ANC) clientele in two tertiary-level health care setups. Samples were collected from all ANC patients requiring transfusion and patients reporting for Indirect Coombs Test (ICT). Data included ICT positive cases with implicated alloantibodies, those requiring specialised procedures and the foetal outcome. The results were described using descriptive statistics by frequencies and percentages. Results: A total of 4683 eligible samples were included in the study, out of 21,893 antenatal patients visiting our setup during study period. One hundred thirty-six ANC patient samples were found to be ICT positive. The most common single alloantibody was anti-D (n = 77, 57.5%). Double antibody positivity was found in 28 patients. Multiple alloantibodies were found in 1 patient. Up to 48% of these allo-anti D cases necessitated specialised procedures. Conclusion: The IHL issues of obstetrics faced in our setup are no less than that in Indian population. We have much higher frequency of double alloantibody in our ANC population. The authors propose that all multiparous ANC patients, especially with a history of transfusion, irrespective of Rh D status should be screened for irregular alloantibodies to circumvent these issues and the last-minute rush for provision of compatible units.

10.
J Org Chem ; 88(7): 4704-4719, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-36893309

RESUMO

Herein, we report Ru(II)-catalyzed C-H/N-H bond functionalization of N-chlorobenzamides with 1,3-diynes via regioselective (4 + 2) annulation for the synthesis of isoquinolones under redox-neutral conditions at room temperature. This represents the first example of C-H functionalization of N-chlorobenzamides using an inexpensive and commercially available [Ru(p-cymene)Cl2]2 catalyst. The reaction is operationally simple, works in the absence of any silver additives, and is also applicable to a broad range of substrates with good functional group tolerance. The synthetic utility of the isoquinolone is demonstrated for the synthesis of bis-heterocycles consisting of isoquinolone-pyrrole and isoquinolone-isocoumarin scaffolds.

11.
Hematol Transfus Cell Ther ; 45(4): 456-460, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36273983

RESUMO

INTRODUCTION: Approximately 55.52% of the Indian population had been fully vaccinated by Jan. 2022, since its first roll out on January 16, 2021. A few concerns were raised concerning the Covishield vaccination related to thrombotic thrombocytopenia. Apheresis-derived platelet concentrates are frequently required in a plethora of clinical situations and post-vaccination decrement of platelet counts might lead to increased deferral of the platelet-pheresis donors. OBJECTIVES: The aim of the study was to discover the effect of the Covishield vaccination on deferral rates of plateletpheresis donors. METHODS: Blood samples were collected from the potential platelet donors for the completion of the standard questionnaire for the complete blood count. The data collected were tabulated in the MS Excel spreadsheet and the biostatistical analysis was performed with the SPSS v23. A p-value of < 0.05 was taken as significant. We compared this data with age- and sex-matched controls. RESULTS: The mean age of cases and controls was 29.69 ± 8.57 and 30.15 ± 7.11, respectively. There was a significant difference in platelet counts of cases (188496.35 ± 72065.66/cumm) and controls (269524.50 ± 53981.60/cumm). Furthermore, donors who received one dose had higher platelet counts of 248676.47 ± 80075.24/cumm than those who received both doses of vaccine (179970.83 ± 66773.73/cumm) . The difference in deferral rates between the two groups was remarkable (34.7% vs. 0.9%, with the p-value < 0.001). CONCLUSION: Vaccination certainly increased the deferral rates of plateletpheresis donors due to low platelet counts. Average platelet counts were low in fully vaccinated individuals, however, the platelets returned to normal counts as the post-vaccination days progressed.

12.
J Org Chem ; 87(19): 12608-12621, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36082518

RESUMO

An external oxidant free Ru(II)-catalyzed C-H functionalization/annulation of primary benzylamines with sulfoxonium ylides has been developed for the synthesis of isoquinolines. The reaction utilizes free amine as a directing group, which is generally considered to be a poor directing group. This work presents the first example of Ru-catalyzed C-H functionalization of benzylamines under redox-neutral conditions. The detection of the amine-directed ruthenacyclic intermediate using high-resolution mass spectrometry corroborated the involvement of free amine as a directing group.


Assuntos
Aminas , Ródio , Aminas/química , Benzilaminas , Catálise , Isoquinolinas/química , Oxirredução , Ródio/química
13.
Biomed Chromatogr ; 36(10): e5433, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35760414

RESUMO

To understand the role of analytics in drug development, regulatory bodies also started using the approach of Quality by Design (QbD) during analytical method developments. The present study deals with the development of the "Method Operable Design Region" for assay and purity determination of risperidone in risperidone drug substance and formulations usingy UHPLC. Five different column chemistries, five different pH buffers, oven temperatures from 25 to 45°C, and different organic modifier composition, column lengths and flow rates were studied and statistically evaluated using Fusion QbD software. The final method parameters were selected by performing multivariable changes in a single run and evaluated using the Monte Carlo simulation approach. The uniqueness of this method is that it is mass compatible, a total of 10 peaks are separated within a short run time of 12.0 min and it uses a "Platforming approach", which means the use of a single method for testing the drug substance, different strengths of a drug product and different formulations. The same method can be also used for the determination of the preservative (benzoic acid) in risperidone 1 mg/ml oral solution. The use of the QbD approach is aligned with the US Pharmacopeia <1220>, BP supplementary chapter 2022 and the International Conference on Harmonization Q14 guidelines for life cycle management of analytical methods.


Assuntos
Projetos de Pesquisa , Risperidona , Cromatografia Líquida de Alta Pressão/métodos , Simulação por Computador
14.
Chem Commun (Camb) ; 57(58): 7164-7167, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34184017

RESUMO

Cp*Co(iii)-catalyzed [4+1] annulation of sulfoxonium ylides with anthranils has been developed for the synthesis of indole-indolone scaffolds. The dual functionality of anthranils was exploited, wherein the nitrogen has been used for C-H amination and the aldehyde group was utilized in the subsequent intramolecular aldol condensation to furnish the corresponding annulated products.

15.
Org Biomol Chem ; 17(32): 7536-7546, 2019 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-31369029

RESUMO

We developed a catalyst-, reagent-, and additive-free protocol with 100% atom economy for the synthesis of diarylmethyl phosphine oxides via 1,6-hydrophosphonylation of p-quinone methides using water as a green solvent. The reaction showed broad scope with excellent functional group tolerance. The practicability of this method was demonstrated by carrying out the reaction on the gram scale whereby product was obtained in high yield by the filtration technique avoiding chromatographic purification.

16.
J Org Chem ; 84(14): 9188-9195, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31273978

RESUMO

Herein, we report Cp*Ir(III)-catalyzed C-H/O-H-bond functionalization of salicylaldehydes with α-diazocarbonyl compounds for the synthesis of chromones under redox-neutral conditions. The reaction proceeds at room temperature and displays excellent functional group tolerance along with high yields of the corresponding products. The developed reaction protocol was successfully applied for the late-stage functionalization of estrone derivative.

17.
Vaccine ; 36(29): 4215-4221, 2018 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-29891350

RESUMO

Foetal Bovine Serum (FBS) and porcine trypsin are one of the essential raw materials used in the manufacturing of cell culture based viral vaccines. Being from animal origin, these raw materials can potentially contaminate the final product by known or unknown adventitious agents. The issue is more serious in case of live attenuated viral vaccines, where there is no inactivation step which can take care of such adventitious agents. It is essential to design production processes which can offer maximum viral clearance potential for animal origin products. Ultraviolet-C irradiation is known to inactivate various adventitious viral agents; however there are limited studies on ultraviolet inactivation of viruses in liquid media. We obtained a recently developed UVivatec ultraviolet-C (UV-C) irradiation based viral clearance system for evaluating its efficacy to inactivate selected model viruses. This system has a unique design with spiral path of liquid allowing maximum exposure to UV-C light of a short wavelength of 254 nm. Five live attenuated vaccine viruses and four other model viruses were spiked in tissue culture media and exposed to UV-C irradiation. The pre and post UV-C irradiation samples were analyzed for virus content to find out the extent of inactivation of various viruses. These experiments showed substantial log reduction for the majority of the viruses with few exceptions based on the characteristics of these viruses. Having known the effect of UV irradiation on protein structure, we also evaluated the post irradiation samples of culture media for growth promoting properties using one of the most fastidious human diploid cells (MRC-5). UV-C exposure did not show any notable impact on the nutritional properties of culture media. The use of an UV-C irradiation based system is considered to be promising approach to mitigate the risk of adventitious agents in cell culture media arising through animal derived products.


Assuntos
Desinfecção/métodos , Viabilidade Microbiana/efeitos da radiação , Soro/virologia , Raios Ultravioleta , Inativação de Vírus/efeitos da radiação , Animais , Bovinos , Técnicas de Cultura de Células/métodos , Desinfecção/instrumentação , Tecnologia Farmacêutica/instrumentação , Tecnologia Farmacêutica/métodos
18.
Chem Commun (Camb) ; 54(49): 6288-6291, 2018 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-29850690

RESUMO

The first Cp*Ir(iii)-catalyzed C-H/N-H bond functionalization of sulfoximines with α-diazocarbonyl compounds has been developed for the synthesis of 1,2-benzothiazines under redox-neutral conditions. The reactions proceed at room temperature with excellent functional group tolerance and high yields without the requirement of any silver additive.

19.
Org Lett ; 19(8): 2186-2189, 2017 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-28406303

RESUMO

Cp*Co(III)-catalyzed C-H functionalization cascade of N-methoxyamides with alkynedione has been reported for the synthesis of indolizidine scaffolds under redox-neutral conditions. The reaction displays broad functional group tolerance along with excellent yield. The reaction proceeds with kinetically relevant C-H bond activation through carboxylate assistance with excellent diastereoselectivity and complete opposite selectivity with respect to alkyne insertion.

20.
J Org Chem ; 82(9): 4998-5004, 2017 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-28421766

RESUMO

Total syntheses of three different lamellarins have been accomplished using a Ru(II)-catalyzed (3 + 2) annulation strategy to construct the central pyrrole ring. The striking features of this synthesis are the use of PEG-400 as a green solvent for the (3 + 2) annulation reaction and multiple catalytic reactions with excellent overall yield. The present route also enables the synthesis of various lamellarin analogues devoid of a B ring.


Assuntos
Cumarínicos/síntese química , Compostos Heterocíclicos de 4 ou mais Anéis/síntese química , Isoquinolinas/síntese química , Catálise , Cumarínicos/química , Éteres , Compostos Heterocíclicos de 4 ou mais Anéis/química , Isoquinolinas/química , Estrutura Molecular , Polietilenoglicóis/química , Rutênio/química , Solventes/química , Análise Espectral/métodos
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