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1.
Beilstein J Org Chem ; 20: 1308-1319, 2024.
Article in English | MEDLINE | ID: mdl-38887569

ABSTRACT

Tandem Diels-Alder reactions are often used for the straightforward formation of complex natural compounds and the fused polycyclic systems contained in their precursors. In the second step of this reaction, regio- and stereochemically controlled intramolecular cyclization leads to the formation of versatile nitrogen-containing tricyclic systems. However, these useful organic transformations are usually carried out in highly toxic organic solvents such as benzene, toluene, chloroform, etc. Despite recent efforts by 'green chemists', synthetic chemists still use these traditional toxic organic solvents in many of their reactions, even though safer alternatives are available. However, in addition to the harmful effects of these petrochemical solvents on the environment, the prediction that their resources will run out in the near future has led 'green chemists' to explore solvents that can be derived from renewable resources and used effectively in various organic transformations. In this context, we have shown for the first time that the 100% atom-economical tandem Diels-Alder reaction between aminofuranes and maleic anhydride can be carried out successfully in vegetable oils and waxes. The reaction was successfully carried out in sunflower seed oil, olive oil, oleic acid and lauryl myristate under mild reaction conditions. A series of epoxyisoindole-7-carboxylic acid and bisepoxyisoindole-7-carboxylic acids were obtained in good yields after a practical isolation procedure. The results obtained in this study demonstrate the potential of vegetable oils and their renewable materials to provide a reaction medium that is more sustainable than conventional organic solvents in cascade Diels-Alder reactions and can be used repeatedly without significant degradation. These materials also allow the reaction to be completed in less time, with less energy consumption and higher yields.

2.
Steroids ; 183: 109011, 2022 07.
Article in English | MEDLINE | ID: mdl-35381272

ABSTRACT

Cholesteryl esters are more nonpolar compounds formed by the conjugation of cholesterol with fatty acids containing a long hydrocarbon chain. These ester molecules do not participate in the composition of the cell membranes and are found in lipid droplets. Because this form of cholesterol can be packaged in a larger amount in lipoproteins, the transport of cholesterol is more effective, and also, these esters play an important role in cholesterol metabolism. Moreover, some of their hydroperoxide derivatives are biologically active components of minimally modified low-density lipoprotein (mmLDL). In recent years, these esters have attracted attention in many industrial and medical applications. In this study, a triphenylphosphine-sulfur trioxide adduct efficiently catalyzed the esterification reactions between homologous long-chain saturated monocarboxylic or dicarboxylic fatty acids and cholesterol molecule in toluene. In these reactions, the triphenylphosphine-based adduct acts as a source of sulfur trioxide. Reactions were performed at 110 °C with equimolar amounts of the reagents except in the case of dicarboxylic acids, and two equimolar of cholesterol was used to afford the corresponding homologous cholesteryl esters in good to excellent yields. The present developed method has advantages such as being simpler, practical, and less toxic than the existing ones as well as enabling the synthesis of the related esters with higher yields.


Subject(s)
Cholesterol Esters , Cholesterol , Cholesterol/metabolism , Esters , Fatty Acids , Lipoproteins, LDL
3.
Carbohydr Res ; 510: 108458, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34634551

ABSTRACT

A convenient protocol for the two component preparation of 1,3-benzoxazines by using several protected and unprotected carbohydrate molecules as organocatalysts have been developed which is broadly applicable to condensation reaction between variety of Mannich bases and paraformaldehyde. This study revealed that fructose have much higher catalytic activity than the other carbohydrates and can be an alternative to metal-containing catalysts as a green renewable organocatalyst for efficient and rapid construction of 1,3-benzoxazine skeleton. In this context, 21 benzoxazine compounds were successfully synthesized and spectral characterizations of these compounds were carried out by spectroscopic methods and elemental analysis. Furthermore, density functional theory (DFT) calculations have been performed to study the detailed mechanism of organocatalyst assisted synthesis of the benzoxazine monomers. The results obtained from these calculations showed that the more realistic reaction pathway involves formation of a phenolate based intermediate which loses a water molecule to form benzenaminium ion. Subsequently, this ion provides the formation of the corresponding benzoxazines with good yields through the intramolecular ring closure step.


Subject(s)
Benzoxazines/chemical synthesis , Carbohydrates/chemistry , Benzoxazines/chemistry , Catalysis , Density Functional Theory , Drug Evaluation, Preclinical , Molecular Structure
4.
Scars Burn Heal ; 7: 20595131211023388, 2021.
Article in English | MEDLINE | ID: mdl-34262789

ABSTRACT

BACKGROUND: Caesarean skin scars (CSS; hypertrophic scars and keloids) are very stressful for women and treatment strategies vary. However, there is a lack of knowledge about the outcome of surgical excision of CSS during caesarean section (CS). The study aims to determine the rate of recurrence and risk factors of recurrence for surgically removed CSS. METHOD: This is a retrospective cohort study that used STROBE guidelines. Pfannenstiel incisions of 145 patients were evaluated. Patients were divided into two groups: recurred (group 1, n = 19) and non-recurred group (group 2, n = 126). The groups were compared. RESULTS: The rate of recurrence of CSS was 13% in the total cohort (19/145), one of the main outcomes of the study. While emergency CS was performed for 12 patients in group 1 (63%), CS was carried out in 25 patients in group 2 (20%); this difference was significant (P = 0.001). Before surgery, white blood cell and neutrophil counts were significantly higher in group 1 (P = 0.014 and P = 0.023, respectively). There were 11 dark-skinned women (26%; Fitzpatrick type 4) in group 1 and 31 (74%) in group 2. This difference was statistically significant (P = 0.031). As the other main outcome, emergency CS could be accepted as a risk factor for recurrence in the multivariate regression analysis (P = 0.060; odds ratio = 5.07; 95% confidence interval = 0.93-17.51). CONCLUSION: The rate of recurrence of surgically removed previous CSS at CS is promising without adjunct therapy. Emergency CS was found to be a risk factor for recurrence. LAY SUMMARY: Background Caesarean skin scars (CSS; hypertrophic scars and keloids) are very stressful and are generally itchy and painful for women. Treatment strategies vary. However, there is a lack of knowledge about the outcome of only surgical excision of CSS scars during caesarean section (CS). The issue being explored There are few data in the literature for CSS in the lower abdomen. These scars can be removed during the second or third CS, but the results are not known exactly. How was the work conducted? In our clinic, 145 patients with CSS were given a CS and their scars were removed at the same time. While most of these scars were reported as hypertrophic by pathological examination, some were reported as keloid. At the earliest, one year after surgery, the rate of recurrence was found to be 13%. What we learned from the study Asymptomatic patients who are planning another pregnancy and do not want to receive any other radiotherapy or steroid injection therapy can wait to remove their CSS at the next CS, especially elective CS with or without adjunct therapy. Emergency CS was found to be a risk factor for the recurrence of these scars.

5.
Swiss Dent J ; (1): 23-24, 2019 Jan 14.
Article in French, German | MEDLINE | ID: mdl-30632358

ABSTRACT

Pregnant women undergo several physiological changes ­ including when it comes to taking medication. Many substances, when taken by the expectant or lactating mother, will be transferred to the foetus or newborn, and not all drugs that help the mother will be beneficial for the baby. Especially in early pregnancy, during organogenesis, the foetus is highly sensitive. If this early development is disturbed by harmful substances such as certain medications, there can be serious consequences. In the worst case, the child is born with a malformation or is limited in its mental development. But later in the course of pregnancy, too, the use of certain drugs is dangerous. Although the risk of malformations now is no longer as high as in the first few weeks, certain drugs can, for example, trigger contractions or affect the baby.


Subject(s)
Dentists , Drug Prescriptions , Lactation , Pregnancy Complications , Breast Feeding , Child , Decision Making , Female , Humans , Infant , Infant, Newborn , Pregnancy , Pregnancy Complications/drug therapy
6.
Swiss Dent J ; (11): 888-889, 2018 Nov 12.
Article in French, German | MEDLINE | ID: mdl-30408948

ABSTRACT

In pregnancy, it is necessary to pay particu­lar attention to oral health, as inflammatory periodontal changes can occur due to the ex­ceptional hormonal situation. The popular be­lief, still existing today, that «each pregnancy costs the woman a tooth¼ is no longer valid considering conventional oral hygiene mea­sures and the fact that most pregnant women are very conscious of their nutrition (diet).


Subject(s)
Oral Hygiene , Periodontal Diseases , Pregnancy Complications , Dentists , Female , Humans , Oral Health , Pregnancy
7.
Mater Sci Eng C Mater Biol Appl ; 93: 539-553, 2018 Dec 01.
Article in English | MEDLINE | ID: mdl-30274087

ABSTRACT

A novel amphiphilic nitrone, N-phenyl-1-(4-((11-(pyridin-1-ium-1yl) undecanoyl) oxy)phenyl)methanimine oxide bromide (NP-1-4-11-PUOPMOB) has been synthesized from a fatty acid derivative as a starting material. Structural characterization of the new compound has been realized by spectroscopic techniques (FTIR, 1H NMR, and 13C NMR). The corrosion inhibition effect of the compound for St37 steel corrosion in 1 M HCl medium has been investigated using experimental (weight loss, electrochemical impedance spectroscopy, potentiodynamic polarization, dynamic electrochemical impedance spectroscopy) and theoretical approaches complemented by surface morphological examination using energy dispersive X-ray spectroscopy, scanning electron microscope, and atomic force spectroscopy. Results from both chemical and electrochemical techniques reveal that the presence of the nitrone in the acid solution impedes St37 steel corrosion. The inhibition efficiency obtained at 125 ppm and 150 ppm concentrations for all methods is found to be over 90%. NP-1-4-11-PUOPMOB behaves as a mixed type corrosion inhibitor according to the potentiodynamic polarization studies. The adsorption of NP-1-4-11-PUOPMOB molecules onto the metal surface follows Langmuir adsorption isotherm and the calculated Kads (equilibrium constant of the adsorption process) value reflects strong interaction. There is evidence of NP-1-4-11-PUOPMOB adsorption on the metal surface from SEM, EDAX, and AFM studies. Experimental and theoretical results are in good agreement.


Subject(s)
Models, Chemical , Nitrogen Oxides/chemistry , Nitrogen Oxides/chemical synthesis , Steel/chemistry , Corrosion , Hydrogen-Ion Concentration
8.
Swiss Dent J ; 128(4): 317-319, 2018 Apr 15.
Article in French, German | MEDLINE | ID: mdl-29669404

ABSTRACT

Antiplatelet agents with the active ingredients acetylsalicylic acid (Aspirin® protect 100), clopidogrel (Iscover®, Plavix®), prasugrel (Efient®) or ticagrelor (Brilique™) prevent the clumping of platelets and thus the formation of small clots at constrictions of the coronary arteries or on the metal struts of stents in the coronary artery or in bypass grafts. Large-scale studies have shown that taken regularly, these drugs can extend life and help prevent heart attacks. Especially in patients with newly implanted stents, the combination of the above-mentioned agents prevents sudden complete occlusion of the vessel concerned. By paying careful attention to contraindications and pursuing the early detection of possible side effects, drug-induced complications can be prevented.


Subject(s)
Platelet Aggregation Inhibitors , Dental Care , Humans , Myocardial Infarction/prevention & control , Platelet Aggregation Inhibitors/therapeutic use
9.
Swiss Dent J ; 127(3): 242-243, 2017.
Article in German | MEDLINE | ID: mdl-28480951

ABSTRACT

Anaphylaxis is defined as a serious allergic or hypersensitivity reaction in the most cases as a result of an IgE-mediated allergic reaction that is rapid in onset and may cause death. Common triggers are foods, insect stings, and medications. The medical treatment includes, epinephrine, glucocorticoids, antihistamines and inhaled bronchodilators, with the aim to prevent progression to life-threatening respiratory and/or cardiovascular symptoms.


Subject(s)
Anaphylaxis/chemically induced , Anaphylaxis/drug therapy , Emergency Medical Services/methods , Epinephrine/therapeutic use , Resuscitation/methods , Anaphylaxis/classification , Anaphylaxis/diagnosis , Heart Arrest/therapy , Humans
10.
Swiss Dent J ; 127(4): 324-325, 2017.
Article in French | MEDLINE | ID: mdl-28480948

ABSTRACT

Anaphylaxis is defined as a serious allergic or hypersensitivity reaction in the most cases as a result of an IgE-mediated allergic reaction that is rapid in onset and may cause death. Common triggers are foods, insect stings, and medications. The medical treatment includes, epinephrine, glucocorticoids, antihistamines and inhaled bronchodilators, with the aim to prevent progression to life-threatening respiratory and/or cardiovascular symptoms.


Subject(s)
Anaphylaxis/chemically induced , Anaphylaxis/drug therapy , Clemastine/therapeutic use , Epinephrine/therapeutic use , Histamine Antagonists/therapeutic use , Methylprednisolone Hemisuccinate/therapeutic use , Resuscitation , Combined Modality Therapy , Humans
11.
Swiss Dent J ; 127(2): 144-145, 2017.
Article in French | MEDLINE | ID: mdl-28266687

ABSTRACT

Rupture of an atherosclerotic plaque is the usual initiating event in an acute coronary syndrome (ACS). Persistent thrombotic occlusion at the site of plaque rupture results in acute myocardial infarction. The early management of the patient is essential and crucially affects the prognosis of an ACS. Management includes the relief of ischemic pain and the initiation of an antithrombotic therapy, including an antiplatelet and anticoagulant therapy with aspirin and heparin to prevent further thrombosis of or embolism from an ulcerated plaque.


Subject(s)
Acute Coronary Syndrome/diagnosis , Acute Coronary Syndrome/etiology , Coronary Thrombosis/diagnosis , Coronary Thrombosis/etiology , Myocardial Infarction/diagnosis , Myocardial Infarction/etiology , Plaque, Atherosclerotic/complications , Plaque, Atherosclerotic/diagnosis , Acute Coronary Syndrome/drug therapy , Anticoagulants/therapeutic use , Coronary Thrombosis/drug therapy , Drug Therapy, Combination , Early Medical Intervention , Humans , Myocardial Infarction/drug therapy , Plaque, Atherosclerotic/drug therapy , Platelet Aggregation Inhibitors/therapeutic use , Prognosis , Rupture, Spontaneous
12.
Swiss Dent J ; 127(1): 38-39, 2017.
Article in German | MEDLINE | ID: mdl-28134969

ABSTRACT

Rupture of an atherosclerotic plaque is the usual initiating event in an acute coronary syndrome (ACS). Persistent thrombotic occlusion at the site of plaque rupture results in acute myocardial infarction. The early management of the patient is essential and crucially affects the prognosis of an ACS. Management includes the relief of ischemic pain and the initiation of an antithrombotic therapy, including an antiplatelet and anticoagulant therapy with aspirin and heparin to prevent further thrombosis of or embolism from an ulcerated plaque.


Subject(s)
Acute Coronary Syndrome/diagnosis , Acute Coronary Syndrome/drug therapy , Anticoagulants/therapeutic use , Aspirin/therapeutic use , Coronary Artery Disease/diagnosis , Coronary Artery Disease/drug therapy , Coronary Thrombosis/diagnosis , Coronary Thrombosis/drug therapy , Heparin/therapeutic use , Platelet Aggregation Inhibitors/therapeutic use , Early Diagnosis , Early Medical Intervention , Humans
13.
Swiss Dent J ; 127(12): 1094-1096, 2017 Dec 11.
Article in German | MEDLINE | ID: mdl-38829581

ABSTRACT

In recent years, the number of patients under long-term treatment with oral anti- coagulants has increased steadily, particularly in the aging population. Dental-surgical treatments of patients who have an increased risk of bleeding due to a drug- induced or congenital clotting disorder are a special challenge for established dental practitioners. The management of the surgical procedure, in cooperation with the patient's attending general practitioner, is a key element of treatment.

14.
J Med Case Rep ; 10(1): 341, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-27906054

ABSTRACT

BACKGROUND: Sinonasal inverted papilloma is a locally aggressive tumor arising from the Schneiderian membrane which lines the nasal cavity and paranasal sinuses. Aggressive surgical approaches, such as lateral rhinotomy, were used until recently for complete removal of the inverted papilloma. Currently, endoscopic resection is the gold standard in the treatment of inverted papilloma. However, there are situations that justify an open approach. For example there are studies that report a higher postoperative recurrence rate after endonasal endoscopic resection, particularly in the treatment of recurrent diseases. While endoscopic resection performed by an experienced surgeon is definitely a minimally invasive therapy, an open approach is not necessarily associated with functional and aesthetic disadvantages. This case report describes the treatment of inverted papilloma by an open approach. This has been described before but the new gold standard of endoscopic resection has to be taken into account before any treatment decision is made nowadays. CASE PRESENTATION: Contrast-enhanced magnetic resonance imaging of the head and neck area was indicated in a 72-year-old white German man who presented with suspected squamous cell carcinoma of his lower lip. Magnetic resonance imaging additionally revealed a 3×2 cm2 polycyclic arranged mucosal thickening with cystic and solid contrast affine shares at the antral laterocaudal area of his right maxillary sinus, extending from his right lateral nasal wall to his maxillary sinus floor. He received antral polypectomy with medial maxillectomy via a unilateral LeFort I osteotomy approach. His pterygoid plate was preserved. A histological examination demonstrated a tumor composed of hyperplastic squamous epithelium protruding into the stroma (surface epithelial cells grew downward into the underlying supportive tissue), thus producing a grossly convoluted cerebriform appearance. Two weeks later, the patient regained a well-formed maxilla without any restrictions. He has remained disease-free for 25 months following the surgery and surveillance was continued in our tumor clinic. CONCLUSIONS: Endoscopic resection of an inverted papilloma continues to be the gold standard. However, some cases require a radical approach. This does not necessarily increase patient morbidity.


Subject(s)
Carcinoma, Squamous Cell/pathology , Maxillary Sinus Neoplasms/pathology , Maxillary Sinus/pathology , Papilloma, Inverted/pathology , Sinus Floor Augmentation/methods , Aged , Carcinoma, Squamous Cell/surgery , Humans , Male , Maxillary Sinus Neoplasms/surgery , Papilloma, Inverted/surgery , Treatment Outcome
15.
Ginekol Pol ; 87(3): 190-3, 2016.
Article in English | MEDLINE | ID: mdl-27306127

ABSTRACT

OBJECTIVES: The aim of our study is the comparison of the results of conventional smear (CC) technique and liquidbased cytology (LBC) technique used as cervical cancer screening methods. MATERIAL AND METHODS: The results of 47954 patients submitted to smear screening in our gynecology clinic between January 2008 and December 2014 have been studied. The smear results have been divided into two groups CC and LBC according to the technique used. RESULTS: When considering the distribution within CC group, the results were as follows: intraepithelial cell abnormalities 2,0% (n=619), insufficient sample for analysis 2,1% (n=660), Atypical squamous cells of undetermined significance (ASC-US) 1.8% (n=554), Low grade squamous intraepithelial lesion (LGSIL) 0.1% (n=35), High grade squamous intraepithelial lesion (HGSIL) 0.1% (n=16), Atypical squamous cells - cannot exclude HGSIL (ASC-H) 0.029% (n=9), Atypical glandular cells- not other wise specified (AGC-NOS) 0.012% (n=4), squamous carcinoma 0.003% (n=1). When considering the distribution in LBC group, the results were as follows: intraepithelial cell abnormalities2.1% (n=357), insufficient sample for analysis 0.9% (n=144), ASC-US 1.8% (n=296), LGSIL 0.2% (n=38), HGSIL 0.1% (n=8), ASC-H 0.1% (n=10), AGC-NOS 0.017% (n=3), squamous carcinoma 0.011% (n=2). CONCLUSIONS: Although the rates of epithelial cell abnormalities are similar for both tests, LSIL results are more frequently observed in LBC technique. In LBC technique, the number of insufficient sample for analysis is quite low compared to CC group and thus constitutes an advantage.


Subject(s)
Atypical Squamous Cells of the Cervix/pathology , Liquid Biopsy/methods , Uterine Cervical Dysplasia/pathology , Vaginal Smears/methods , Adult , Female , Humans , Uterine Cervical Neoplasms/pathology
17.
Swiss Dent J ; 126(2): 150-1, 2016.
Article in French | MEDLINE | ID: mdl-26915930

ABSTRACT

Gutta-percha is a tough plastic substance from the latex of several Malaysian trees of the sapodilla family that resembles rubber but contains more resin. It is especially used as insulation and in dentistry. Gutta-percha endodontic filling points were found to contain approximately 20% gutta-percha (matrix), 66% zinc oxide (filler), 11% heavy metal sulphates (radiopacifier), and 3% waxes and/or resins (plasticiser). The mechanical properties were indicative of a partially crystalline viscoelastic polymeric material.


Subject(s)
Gutta-Percha/therapeutic use , Root Canal Obturation/methods , Gutta-Percha/chemistry , Resins, Synthetic/analysis , Viscoelastic Substances
18.
Swiss Dent J ; 126(1): 40-1, 2016.
Article in German | MEDLINE | ID: mdl-26797818

ABSTRACT

Gutta-percha is a tough plastic substance from the latex of several Malaysian trees of the sapodilla family that resembles rubber but contains more resin. It is especially used as insulation and in dentistry. Gutta-percha endodontic filling points were found to contain approximately 20% gutta-percha (matrix), 66% zinc oxide (filler), 11% heavy metal sulphates (radiopacifier), and 3% waxes and/or resins (plasticiser). The mechanical properties were indicative of a partially crystalline viscoelastic polymeric material.


Subject(s)
Dental Implantation, Endosseous, Endodontic , Gutta-Percha/chemistry , Gutta-Percha/therapeutic use , Humans , Viscoelastic Substances
19.
Swiss Dent J ; 125(12): 1364-7, 2015.
Article in French, German | MEDLINE | ID: mdl-26678716

ABSTRACT

Since the 1950s, oxidised regenerate cellulose (TABOTAMP ®) has been successfully applied for local haemostasis in intra- or postoperative bleeding complications. The scope of this medical product is large and it has found its place in oral and maxillofacial surgery. Although the application of TABOTAMP ® in medicine and dentistry is common, further complications next to the absence of the haemostatic effect may be encountered if used incorrectly. The aim of this article is an update on the proper use of TABOTAMP ®. Further, tips are provided for the indication-specific application of this useful agent in clinical practice.

20.
Swiss Dent J ; 125(7-8): 830-831, 2015.
Article in German | MEDLINE | ID: mdl-26345398

ABSTRACT

Chlorhexidine, one of the most frequently prescribed medications, belongs to a group of medicines called antiseptic antibacterial agents. It is indicated as a mouthwash in the treatment of gingivitis, as it cleans the skin after injury and can be used to clean hands before a procedure. Chlorhexidine works by killing or preventing the growth of bacteria on the mucosa or skin. It should not be used in individuals who are known to be hypersensitive to Chlorhexidine gluconate or other ingredients. It may cause some reversible tooth discoloration or an increase in tartar formation.

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