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E- and Z-9-Methyldeca-3,8-dien-1-ols undergo smooth cyclization with aldehydes in the presence of 20 mol% AgSbF6 under extremely mild conditions to generate the corresponding oxa-bicycles in good yields with excellent selectivity. In fact, E-olefin affords the trans-product exclusively, whereas the Z-olefin gives the cis-product predominantly. In the case of E- or Z-8-methylnona-3,8-dien-1-ol, the product is formed via the termination of Prins cyclization with an allylic C-H bond through olefin migration. The termination of Prins cyclization with tethered olefin is an unprecedented reaction, which provides a useful motif of various natural products.
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Compostos Bicíclicos com Pontes/síntese química , Compostos Bicíclicos com Pontes/química , Ciclização , Estrutura Molecular , EstereoisomerismoRESUMO
The concept of physicians referring patients to their own healthcare entities is considered a "self-referral". A discerning factor of a self-referral is when the physician has a financial interest in the entity of patient referral. Prospects of healthcare overutilization and costs, thereby, rise. Self-referral laws, therefore, are important to regulate overutilization and contain costs. In the 1980s, Congressman Fortney Stark initiated an act that was one of the precursors to one such self-referral law, known as the Stark Law. The Stark Law, in its initial phase, known as Stark I, addressed self-referrals selectively from laboratory services. Stark I, thereafter, in a series of subsequent amendments and enactments, burgeoned to include multiple services, referred as Designated Health Services (DHS), for self-referrals. The expanded law, inclusive of those DHS, is now known as Stark II. The passage of the 2010 Affordable Care Act as well as the prevailing 2019 Coronavirus Disease (COVID-19) pandemic further modified the Stark Law. Given the legislative history of the said law, the present review curates the legal initiatives of this law from its nascent formative stages to the present form. The purpose of the above curation is to present a bird's eye view of its evolution and present analysts of any future research segments. This review, furthermore, describes the waivers of this law specific to COVID-19, or COVID-19 blanket waivers, which are instruments to assuage any barriers and further placate any hurdles arising from this law prevalent in this pandemic.
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The Emergency Medical Treatment & Active Labor Act (EMTALA) is a healthcare law specific to screening, stabilizing, and transferring (or accepting) patients with emergency medical conditions and active labor. This law, contextual to Medicare-participating hospitals, ensures public access to emergency medical services, regardless of the individual's ability to pay. The Defensive Medicine (DM) model and Physician Responsiveness to Standard-of-care Reforms (PRSRs) model are two medical malpractice frameworks leveraged in this paper. The nodes of these frameworks comprise of the treatment-versus-no-treatment dynamics and cutoff thresholds. Cutoff thresholds are specific to health risks and treatment price rates. Health risks stem from those with treating or not treating a patient as well as those inherent from the patient's ailment. Treatment price rates are subcategorized into customary and efficient price rates. Given the above nodes of these frameworks, this paper examines how the above medical malpractice models synchronize and sequentially align with the legal obligations of this law. This paper, furthermore, contemplatively describes how the incentivize/penalize dynamics interrelate to the push/pull dynamics of the PRSRs malpractice model. Thereafter, this paper applies the above push/pull dynamics contextual to the three specific obligations of this law, essentially, screening, stabilizing, and transferring (or accepting) emergency care patients. Conclusively, this paper illustrates the above network in a cascading algorithm that ligates the nodes of these frameworks to EMTALA's obligations.
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The definition of defensive medicine has evolved over time given various permutations and combinations. The underlying meaning, however, has persisted in its relevance towards two classifications, positive and negative defensive medicine. Positive defensive medicine is specific to overutilization, excessive testing, over-diagnosing, and overtreatment. Negative defensive medicine, on the contrary, is specific to avoiding, referring, or transferring high risk patients. Given the above bifurcation, the present research analyzes defensive medicine in the landscape of medical errors. In its specificity to medical errors, we consider the cognitive taxonomies of medical errors contextual to execution and evaluation slips and mistakes. We, thereafter, illustrate how the above taxonomy interclasps with five classifications of medical errors. These classifications are those that involve medical errors of operative, drug-related, diagnostic, procedure-related, and other types. This analytical review illustrates the nodular frameworks of defensive medicine. As furtherance of our analysis, this review deciphers the above nodular interconnectedness to these error taxonomies in a cascading stepwise sequential manner. This paper was designed to elaborate and to stress repeatedly that practicing defensive medicine entails onerous implications to physicians, administrators, the healthcare system, and to patients. Practicing defensive medicine, thereby, is far from adhering to those optimal healthcare practices that support quality of care metrics/milestones, and patient safety measures. As an independent standalone concept, defensive medicine is observed to align with the taxonomies of medical errors based on this paper's diagrammatic and analytical inference.
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A series of isomeric 2-aryl-6,6-dimethyltetrahydro-5-quinolinones (set I) and 2-aryl-7,7-dimethyltetrahydro-5-quinolinones (set II) were studied under positive ion electron ionization (EI) and electrospray ionization (ESI) techniques. Under EI conditions, the molecular ions were found to be less stable in set I isomers, and they resulted in abundant fragment ions, i.e., [M-CH(3)](+), [M-CO](+.), [M-HCO](+), [M-(CH(3),CO)](+), and [M-(CH(3),CH(2)O)](+), when compared with set II isomers. In addition, the set I isomers showed specific fragment ions corresponding to [M-OH](+) and [M-OCH(3)](+). The retro-Diels-Alder (RDA) product ion was always higher in set II isomers. The ESI mass spectra produced [M + H](+) ions, and their decomposition showed favorable loss of CH(3) radical, CH(4) and C(2)H(6) molecules in set I isomers. The set II isomers, however, showed predominant RDA product ions, and specific loss of H(2)O. The selectivity in EI and ESI was attributed to the instability of set I isomers by the presence of a gem-dimethyl group at the α-position, and it was supported by the data from model compounds without a gem-dimethyl group. Density functional theory (DFT) calculations successfully corroborated the fragmentation pathways for diagnostic ions. This study revealed the effect of a gem-dimethyl group located at the α-position to the carbonyl having aromatic/unsaturated carbon on the other side of the carbonyl group.
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Quinolonas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Íons/química , Isomerismo , Modelos QuímicosRESUMO
CONTEXT: Autoantibodies have a role in the diagnosis and prognosis in Autoimmune Inflammatory Myositis (AIM). AIMS: The aim of this work was to study the prevalence and clinical correlation of myositis specific and associated antibodies (MSA and MAA) in AIM. SETTING AND DESIGN: This was a cross-sectional observational study. METHODS AND MATERIALS: Consecutive AIM patents were divided into groups as dermatomyositis (DM), polymyositis (PM), CTD-associated myositis (CTD-M), cancer-associated myositis (CAM) and juvenile myositis (JM). Their data along with serum samples were collected after obtaining informed consent. Sera was analyzed for IgG antibodies against Jo-1, PL-7, PL-12, EJ, SRP, Mi-2, MDA-5, TIF1γ, SAE1, SAE2, NXP2 and SSA/R052kD using the microELISA technique. The institutional ethics committee approved the study. STATISTICAL ANALYSIS: SPSS software (version 24.0) was used. P value < 0.05 was considered statistically significant. RESULTS: There were 48 patients (DM = 19, PM = 19, CTD-M = 5, CAM = 2, JM = 3) included. MSA were positive in 37.5% patients. Antibodies against Mi-2 were present in 6 (12.5%), Jo-1 in 5 (10.4%), 2 (4.1%) each had PL-7 and SRP antibodies. One patient (2%) each had MDA-5, NXP2 and TIf1g antibodies. Jo-1 antibody was associated with mechanic's hands and ILD. There was a significant association of rash in the Mi-2 group with none of the patients having ILD. Malignancy screening was negative in NXP2 and TIF1g antibody-positive patients. Ro52 was the most common MAA (33.3%) and was associated with mechanic's hand. CONCLUSION: MSA was present in almost 40% of the cohort. Anti Jo-1 antibody was associated with mechanic's hands and ILD. None of the Mi-2 patients had ILD, which may point to a protective role of this antibody for ILD. The association of newer antibodies in Indian patients needs to be further studied in larger cohorts.
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A simple method has been employed to synthesize a cyclotriphosphazene appended with six porphyrins. The reaction of one equivalent of hexachlorocyclotriphosphazene with six equivalents of 5-(4-hydroxyphenyl)-10,15,20-tri(p-tolyl)porphyrin or -21-thiaporphyrin in tetrahydrofuran in the presence of cesium carbonate, followed by simple column-chromatography purification, afforded the hexaporphyrinato cyclotriphosphazene systems as the single products in 80-90 % yields. The metal(II) derivatives (Cu(II), Zn(II)) of the hexaporphyrinato cyclotriphosphazene systems were prepared by treating the hexaporphyrin assemblies with the appropriate metal salts under standard metallation conditions. The compounds are freely soluble in common organic solvents and were characterized by mass spectrometry, NMR, absorption, and fluorescence spectroscopy, and electrochemical techniques. Material studies carried out by using fluorescence microscopy, SEM, and AFM techniques showed that the hexaporphyrinato cyclotriphosphazene systems form ringlike architectures. Preliminary biological studies indicate that the hexacopper(II) porphyrin assembly can be used as an artificial nuclease.
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Abdominal Epilepsy (AE) is a variant of temporal lobe epilepsy and is commonly seen in pediatric age group. There are however, multiple reports of abdominal epilepsy in adolescents and even in adults. Chronic and recurrent gastrointestinal symptoms with one or more neuropsychiatric manifestations are often the presenting picture for a patient with AE. Such patients therefore, are more likely to consult a general practioner, a physician, a surgeon or a gastroenterologist than consulting a psychiatrist or a neurologist. We hereby present such a case of AE in an adult with review of similar reports.
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We have recently treated a case of acute anterior wall myocardial infarction who developed prolonged respiratory failure. The clinical details and possible mechanism are discussed.
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A series of novel N- and O- perfluoroalkyl triazole tagged thienopyrimidines 6a-c and 7a-d was synthesized in two steps from thienopyrimidin-4-ones 2 through O- and N-propargylated regioisomers 3a-i and 4a-i respectively. Compound 2 was reacted with propargyl bromide to form O- and N-propargylated regioisomers 3 and 4 in definite proportions. Each regioisomer was separated and independently subjected to [3+2] cycloaddition using perfluoroalkyl azides through Click reaction under Sharpless conditions and obtained exclusively anti product in each case. The formation of two regioisomers in the first step and single anti addition product in the next step could be explained based on computational studies carried out at B3LYP/6-31G(d) level of theory. Results of Fukui function indices at the reactive centers are in accordance with the observations. On evaluation of the synthesized molecules for their binding affinities towards adenosine receptors, 4d and 4f were found to be selective to A1 over A2A receptors.
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Simulação por Computador , Pirimidinas/química , Pirimidinas/síntese química , Receptores Purinérgicos P1/química , Termodinâmica , Triazóis/química , Animais , Sítios de Ligação , Ciclização , Desenho de Fármacos , Ligantes , Modelos Moleculares , Pirimidinas/farmacologia , Ratos , Relação Estrutura-AtividadeRESUMO
The formation of N- and O-propargylated quinazoline derivatives 2, 3 from quinazol-4-ones 1 was theoretically predicted by optimizations at B3LYP/6-31G* level, analysed kinetically and thermodynamically. Theoretical predictions are validated by experiment to observe the trends and found deviation. Thus, compound 1 was propargylated in basic media to obtain compound 2 and 3 in definite proportions. Each compound was further subjected to [3+2] cycloaddition using perfluoroalkyl azides through Click reaction under Sharpless conditions, and obtained a series of novel perfluoroalkyl-1H,1,2,3-triazol-4-yl substituted quinazolines 4, 5, and 6. All the compounds were screened for antimicrobial activity and identified potential compounds.
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Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Quinazolinas/química , Quinazolinas/farmacologia , Triazóis/química , Anti-Infecciosos/síntese química , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Conformação Molecular , Quinazolinas/síntese química , Reprodutibilidade dos Testes , TermodinâmicaRESUMO
Diene-dienophile competing Diels-Alder reaction pathways of cyclopentadiene, 1H-, 2H- and 3H-phospholes with butadiene were explored at the B3LYP level using 6-31G(d) and 6-311+G(d,p) basis sets, and at the CCSD(T)/6-31G(d)//B3LYP/6-31G(d) level. Activation barriers show that cyclopentadiene favors a diene rather than a dienophile conformation. Pathways 1 and 2 (A and B) corresponding to butadiene as the diene and dienophile are predicted to be highly competitive in the case of 1H-phosphole. Secondary orbital interactions and the preferable bispericyclic nature of transition states are responsible for the stability of endo transition states. The study indicates that some of the transition states are bispericyclic and most of them are highly asynchronous. The reactions require a lower activation energy when the conversion of weak C=P to C-P occurs in the case of 2H- and 3H-phospholes. The high stability of the products resulting via path 1 can be attributed to the less strain in the bicyclo[4.3.0]nonadiene skeleton compared to the norbornene derivatives obtained from path 2. Activation and reaction energy values for these Diels-Alder reaction pathways are compared with the values reported for the [4+2] cyclodimerizations of each of the reactants to examine the likelihood of cyclodimerizations along these pathways.