171 research outputs found
Utility of N-2-pyridyl-3-oxobutanamide in heterocyclic synthesis: Synthesis of new dihydropyridine, fused pyridine, pyridopyridine, pyridazine and pyridopyrimidinethione derivatives
2-Aminopyridine was fused with ethyl acetoacetate without solvent for two hours to yield the  N-2-pyridylâ3-oxobutanamide 1. However, when the reaction time was increased to 5 hours a structure 3 was obtained. Condensation of the structure 3 with benzaldehyde gave 4. The reaction of pyridopyridone 3 with arylidenemalononitrile7a-c afforded 4 H-pyran derivative 10a-c. In contrast to the behavior of arylidenemalononitrile 7a-c towards pyridopyridine3, benzylidenemalononitrile 7d reacted withcompound 3 to give a product 11. Compound 1 was allowed to react with arylidenemalononitrile to give the dihydropyridine derivative 17a-d. Alkylation of compound 1 with alkylating agents has been also reported. Thus, compound 1 was condensed with [DMF-DMA] in refluxing dioxane to yield 18, but under the reaction conditions we obtained only 21. The pyridopyridone 3 reacted with benzoylisothiocyanate 25a,b to give thiourea derivatives 26a,b Cyclization of 26a,b in dry dioxane and conc. sulphuric acid afforded pyridopyrimidinethione derivatives 27a,b. On the other hand, coupling of pyridopyridine 3 with the aromatic diazonium salt 28a-e afforded the corresponding azo products 29a-e. Boiling of compound 29 in aqueous solution of HCl afforded the hydrazo products 30. Treatmentof arylhydrazone 30a with malononitrile afforded the pyridazine derivatives 31
Effects of irregular antenatal care attendance in primiparas on the perinatal outcomes: a cross sectional study
Aim: Antenatal care (ANC) is a key strategy for reducing maternal and neonatal morbidity and mortality rates because adequate utilization of antenatal health care services is associated with improved maternal and neonatal health outcomes. The current study aims to identify the factors causing lack of regular attendance at ANC clinics in primiparas and to determine the effects of lack of antenatal care on perinatal outcomes.
Methods: A cross sectional study was carried out at Assiut Women\u27s Health Hospital, Egypt between October 2015 and September 2016. Estimated sample size of 516 primiparous women were divided into two groups according to number of attendance to ANC clinics; women who came four visits or more were considered regular and those who came to less than four visits were considered irregular. Data was collected via a structured interview questionnaire that included personal data, obstetrical, data about current pregnancy and labor. The researcher interviewed the women within 24 hours postpartum.
Results: The majority of the study sample (74.8%) had regular ANC visits while only (25.2%) had \u3c4 antenatal visits. Financial problems (44.6%) or lack of awareness about the importance of ANC (20%) were the most common reasons for irregular ANC visits. The incidence of preeclampsia and eclampsia is significantly higher in the irregular attendants (p=0.000). Similarly, preterm birth, stillbirth and low birth weight were significantly more common among irregular attendants (p=0000).
Conclusion: Women with irregular antenatal care attendance are much more prone to pregnancy complications such as preeclampsia, eclampsia and anemia besides higher adverse birth outcomes including preterm birth, low birth weight and stillbirth
Effect of Using Intracanal Cryotherapy Versus Ultrasonic Activated Irrigation on Post-Operative Pain in Single Visit Endodontic Treatment of Teeth with Symptomatic Irreversible Pulpitis âRandomized Clinical Trialâ
Aim : This study was designated to evaluate the effect of using intracanal cryotherapy versus ultrasonic activated irrigation on postoperative pain in single visit endodontic treatment of mandibular first molar with symptomatic, irreversible pulpitis using numerical rate scale (NRS) at 6, 12, 24, 48,72 hr and 1 week postoperatively.
Materials and Methods: seventy-eight patients diagnosed with symptomatic irreversible pulpitis in mandibular first molar with no periapical involvement. The cases were randomly divided into three groups according to final irrigation protocol after root canal preparation using Pro Taper Next; Groups A, B and C, twenty-six patients each group (n=26). Group A: final irrigation with room temperature saline using Navi-Tip; double side-port needle (31-gauge,27mm). Group B: final irrigation with room temperature saline with ultrasonic activation using (Ultra-X). Group C: final irrigation with 2.5Âșc cold saline using Navi-Tip; double side-port needle (31-gauge,27mm). After a single visit root canal treatment and a specific final irrigation protocol, depending on each group, the patients were given a questionnaire on which the patient would mark the degree of pain in a scale from 0 to 10 at 6, 12, 24, 48, and 72 h and 7 days post-obturation. Data were statistically analyzed with a significance level of p †0.05.
Results: ultrasonic group (Group B) showed statistically the least incidence and intensity of postoperative pain compared to the other groups after 6, 12 and 24 hours. Cryotherapy group (group B) showed lower Incidence and intensity of postoperative pain after 6,12, 24 and 48 hours. While control group (group A) showed statistically the highest incidence and intensity of post-operative pain compared to the other groups after 6,12, 24,48 and 72 hours. After 1 week there were no significant difference among the three groups where pain scores declined among the groups till it reaches score (0) at day 7. Incidence and number of analgesic intake was significantly higher in patients of the control group compared to ultrasonic and cryotherapy groups.
Conclusion: The least post-operative pain incidence and intensity were associated with ultrasonic irrigation on the first day. The incidence and severity of post-endodontic pain are decreased when cold saline (cryotherapy) is used as the final irrigant during endodontic treatment of teeth with symptomatic irreversible pulpitis
Reduction of helium permeation in microfabricated cells using aluminosilicate glass substrates and AlO coatings
The stability and accuracy of atomic devices can be degraded by the evolution
of their cell inner atmosphere. Hence, the undesired entrance or leakage of
background or buffer gas, respectively, that can permeate through the cell
walls, should be slowed down. In this work, we investigate helium permeation in
microfabricated alkali vapor cells filled with He and whose windows are made of
borosilicate glass (BSG) or aluminosilicate glass (ASG). The permeation is then
derived from routine measurements of the pressure-shifted hyperfine transition
frequency of an atomic clock. We first confirm that ASG reduces He permeation
rate by more than two orders of magnitude, in comparison with BSG. In addition,
we demonstrate that AlO thin-film coatings, known to avoid alkali
consumption in vapor cells, can also significantly reduce He permeation. The
permeation through BSG is thereby reduced by a factor 110 whereas the one
through ASG is decreased by a factor up to 5.8 compared to uncoated substrates.
These results may contribute to the development of miniaturized atomic clocks
and sensors with improved long-term stability or sensitivity.Comment: 7 pages, 5 figure
Evaluation of the effect of hypericum triquetrifolium turra on memory impairment induced by chronic psychosocial stress in rats: Role of BDNF
Background: Chronic psychosocial stress impairs memory function and leads to a depression-like phenotype induced by a persistent status of oxidative stress. Hypericum perforatum L. (St. Johnâs wort) is widely used to relieve symptoms of anxiety and depression; however, its long-term use is associated with adverse effects. Hypericum triquetrifolium Turra is closely related to H. perforatum. Both plants belong to Hypericaceae family and share many biologically active compounds. Previous work by our group showed that methanolic extracts of H. triquetrifolium have potent antioxidant activity as well as high hypericin content, a component that proved to have stress-relieving and antidepressant effects by other studies. Therefore, we hypothesized that H. triquetrifolium would reduce stress-induced cognitive impairment in a rat model of chronic stress. Objective: To determine whether chronic treatment with H. triquetrifolium protects against stress-associated memory deficits and to investigate a possible mechanism. Methods: The radial arm water maze (RAWM) was used to test learning and memory in rats exposed to daily stress using the resident-intruder paradigm. Stressed and unstressed rats received chronic H. triquetrifolium or vehicle. We also measured levels of brain-derived neurotrophic factor (BDNF) in the hippocampus, cortex and cerebellum. Results: Neither chronic stress nor chronic H. triquetrifolium administration affected performance during acquisition. However, memory tests in the RAWM showed that chronic stress impaired different post-encoding memory stages. H. triquetrifolium prevented this impairment. Furthermore, hippocampal BDNF levels were markedly lower in stressed animals than in unstressed animals, and chronic administration of H triquetrifolium chronic administration protected against this reduction. No significant difference was observed in the effects of chronic stress and/or H. triquetrifolium treatment on BDNF levels in the cerebellum and cortex. Conclusion: H. triquetrifolium extract can oppose stress-associated hippocampus-dependent memory deficits in a mechanism that may involve BDNF in the hippocampus
Fungal Systematics and Evolution: FUSE 6
Fungal Systematics and Evolution (FUSE) is one of the journal series to address the âfusionâ between morphological data and
molecular phylogenetic data and to describe new fungal taxa and interesting observations. This paper is the 6th contribution in
the FUSE seriesâpresenting one new genus, twelve new species, twelve new country records, and three new combinations. The
new genus is: Pseudozeugandromyces (Laboulbeniomycetes, Laboulbeniales). The new species are: Albatrellopsis flettioides from
Pakistan, Aureoboletus garciae from Mexico, Entomophila canadense from Canada, E. frigidum from Sweden, E. porphyroleucum
from Vietnam, Erythrophylloporus flammans from Vietnam, Marasmiellus boreoorientalis from Kamchatka Peninsula in the
Russian Far East, Marasmiellus longistipes from Pakistan, Pseudozeugandromyces tachypori on Tachyporus pusillus (Coleoptera,
Staphylinidae) from Belgium, Robillarda sohagensis from Egypt, Trechispora hondurensis from Honduras, and Tricholoma
kenanii from Turkey. The new records are: Arthrorhynchus eucampsipodae on Eucampsipoda africanum (Diptera, Nycteribiidae)
from Rwanda and South Africa, and on Nycteribia vexata (Diptera, Nycteribiidae) from Bulgaria; A. nycteribiae on Eucampsipoda
africanum from South Africa, on Penicillidia conspicua (Diptera, Nycteribiidae) from Bulgaria (the first undoubtful
country record), and on Penicillidia pachymela from Tanzania; Calvatia lilacina from Pakistan; Entoloma shangdongense from
Pakistan; Erysiphe quercicola on Ziziphus jujuba (Rosales, Rhamnaceae) and E. urticae on Urtica dioica (Rosales, Urticaceae)
from Pakistan; Fanniomyces ceratophorus on Fannia canicularis (Diptera, Faniidae) from the Netherlands; Marasmiellus biformis
and M. subnuda from Pakistan; Morchella anatolica from Turkey; Ophiocordyceps ditmarii on Vespula vulgaris (Hymenoptera,
Vespidae) from Austria; and Parvacoccum pini on Pinus cembra (Pinales, Pinaceae) from Austria. The new combinations
are: Appendiculina gregaria, A. scaptomyzae, and Marasmiellus rodhallii. Analysis of an LSU dataset of Arthrorhynchus including
isolates of A. eucampsipodae from Eucampsipoda africanum and Nycteribia spp. hosts, revealed that this taxon is a complex
of multiple species segregated by host genus. Analysis of an SSUâLSU dataset of Laboulbeniomycetes sequences revealed support
for the recognition of four monophyletic genera within Stigmatomyces sensu lato: Appendiculina, Fanniomyces, Gloeandromyces,
and Stigmatomyces sensu stricto. Finally, phylogenetic analyses of Rhytismataceae based on ITSâLSU ribosomal DNA
resulted in a close relationship of Parvacoccum pini with Coccomyces strobi
Surface modification of starch based blends using potassium permanganate-nitric acid system and its effect on the adherence and proliferation of osteoblastic-like cells
The surface modification of three starch based polymeric biomaterials, using a KMnO4/NHO3 oxidizing system, and the effect of that modification on the osteoblastic cell adhesion has been investigated. The rationale of this work is as followsâstarch based polymers have been proposed for use as tissue engineering scaffolds in several publications. It is known that in biodegradable systems it is quite difficult to have both cell adhesion and proliferation. Starch based polymers have shown to perform better than poly-lactic acid based materials but there is still room for improvement. This particular work is aimed at enhancing cell adhesion and proliferation on the surface of several starch based polymer blends that are being proposed as tissue engineering scaffolds.
The surface of the polymeric biomaterials was chemically modified using a KMnO4/HNO3 system. This treatment resulted in more hydrophilic surfaces, which was confirmed by contact angle measurements. The effect of the treatment on the bioactivity of the surface modified biomaterials was also studied. The bioactivity tests, performed in simulated body fluid after biomimetic coating, showed that a dense film of calcium phosphate was formed after 30 days. Finally, human osteoblast-like cells were cultured on unmodified (control) and modified materials in order to observe the effect of the presence of higher numbers of polar groups on the adhesion and proliferation of those cells. Two of the modified polymers presented changes in the adhesion behavior and a significant increase in the proliferation rate kinetics when compared to the unmodified controls.FCT (Portugal) for providing the postdoctoral grant (BPD/8491/2002)
- âŠ