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11.
BackgroundPenicillium produces a wide range of structurally diverse metabolites with significant pharmacological impacts in medicine and agriculture. For the first time, a complete metabolome of Penicillium claviforme (P. claviforme) (FBP-DNA-1205) was studied alongside pharmacological research in this study.MethodsThe metabolic profile of P. claviforme fermented on Potato Dextrose Broth (PDB) was investigated in this work. The complete metabolomics studies of fungus were performed using GC-MS and LC-MS-QTOF techniques. An in vitro model was utilised to study the cytotoxic and antioxidant activities, while an in vivo model was employed to investigate the antinociceptive and acute toxicity activities. Molecular Operating Environment (MOE) software was used for molecular docking analysis.ResultsGC-MS study showed the presence of alkanes, fatty acids, esters, azo and alcoholic compounds. Maculosin, obtain, phalluside, quinoline, 4,4’-diaminostilbene, funaltrexamine, amobarbital, and fraxetin were among the secondary metabolites identified using the LC-MS-QTOF technique. The n-hexane fraction of P. claviforme displayed significant cytotoxic activity in vitro, with an LD50 value of 92.22 µgml−1. The antinociceptive effects in vivo were dose-dependent significantly (p < .001). Interestingly, during the 72 h of investigation, no acute toxicity was demonstrated. In addition, a docking study of tentatively identified metabolites against the inflammatory enzyme (COX-2) supported the antinociceptive effect in an in silico model.ConclusionMetabolic profile of P. claviforme shows the presence of biologically relevant compounds in ethyl acetate extract. In addition, P. claviforme exhibits substantial antioxidant and cytotoxic activities in an in vitro model as well as antinociceptive activity in an in vivo model. The antinociceptive action is also supported by a molecular docking study. This research has opened up new possibilities in the disciplines of mycology, agriculture, and pharmaceutics.

Key messages

  • The first time explored complete metabolome through GC-MS and LC-MS-QTOF.
  • Both in vivo & in vitro pharmacological investigation of P. claviforme.
  • In silico molecular docking of LC-MS-QTOF metabolites.
  相似文献   
12.
In this study, an artificial intelligence tool called gene expression programming (GEP) has been successfully applied to develop an empirical model that can predict the shear strength of steel fiber reinforced concrete beams. The proposed genetic model incorporates all the influencing parameters such as the geometric properties of the beam, the concrete compressive strength, the shear span-to-depth ratio, and the mechanical and material properties of steel fiber. Existing empirical models ignore the tensile strength of steel fibers, which exercise a strong influence on the crack propagation of concrete matrix, thereby affecting the beam shear strength. To overcome this limitation, an improved and robust empirical model is proposed herein that incorporates the fiber tensile strength along with the other influencing factors. For this purpose, an extensive experimental database subjected to four-point loading is constructed comprising results of 488 tests drawn from the literature. The data are divided based on different shapes (hooked or straight fiber) and the tensile strength of steel fiber. The empirical model is developed using this experimental database and statistically compared with previously established empirical equations. This comparison indicates that the proposed model shows significant improvement in predicting the shear strength of steel fiber reinforced concrete beams, thus substantiating the important role of fiber tensile strength.  相似文献   
13.
The aim of the present study was to evaluate the effect of brushing with two whitening dentifrices (Colgate Optic White (COW) and Colgate Optic White Charcoal (COC)) on surface gloss, micro-roughness, and micro-hardness of nanostructured hybrid conventional (Z350) and bulk-fill (Tetric N Ceram bulk-fill) polymer composite. In total, 96 disk samples using two nano-hybrid composite polymers (Z350 and Tetric N Ceram Bulk-fill) were prepared. All specimens were exposed to two different dentifrices (COW and COC), resulting in four main subgroups in the study. Specimens were assessed for surface gloss, micro-roughness (Ra), and micro-hardness using standardized methodology. Means and standard deviations of properties compared using paired t-test, one-way and two-way ANOVA, and post hoc test. The presence of dentifrices did not show any significant difference in micro-hardness values of Z350 (p > 0.05), whereas micro-hardness of bulk-fill composite significantly reduced on dentifrices exposure (p ≤ 0.05). Bulk-fill polymer composite showed significant reduction in gloss after dentifrice exposure (p < 0.05), however, Z350 showed no significant loss of gloss due to dentifrices (p > 0.05). A significant increase in Ra was observed for both resin materials after exposure to dentifrices (COC and COW). Conventional resin composite (Z350) showed comparable surface hardness and gloss before and after dentifrice exposure, however, micro-roughness increased significantly due to dentifrice exposure. Bulk-fill resin (Tetric N Ceram) showed significant loss of micro-hardness and gloss and increase in micro-roughness on dentifrice exposure. Conventional nano-hybrid composite polymer showed better durability in resisting loss of surface properties compared to bulk-fill resin polymer in the present experiment.  相似文献   
14.
Rational modification of molecular structure by incorporating electron donating groups can play a potential role for designing aggregation induced emission (AIE) active fluorescent probes. Based on this principle, fluorescent probes (1a–c) were synthesized, and they displayed excellent aggregation induced emission (AIE) behavior in a H2O/DMF (4 : 1, v/v) mixture due to restrictions in intramolecular charge transfer (ICT). As a comparison, probe 1d was synthesized by installing an electron withdrawing (–NO2) group that surprisingly quenched the aggregation behaviour. Additionally, AIE active probes 1a–c displayed a highly sensitive dual channel (fluorometric and colorimetric) response towards rapid detection of CN, which is an active toxic material. Probes 1a–c showed selectively enhanced fluorescence emission behavior towards CN with detection limits of 1.34 ppb, 1.38 ppb, and 1.54 ppb, respectively. The sensing mechanism involves Michael type adduct formation due to the nucleophilic addition reaction of cyanide with probes and was confirmed through 1H NMR titration experiments. In contrast, probe 1d containing an electron withdrawing moiety showed insensitivity towards CN. Therefore, this study provides the efficient strategy to induce AIE character in fluorescent probes and expands the mechanistic approach toward the sensing of toxic CN.

Rational modification of molecular structure by incorporating electron donating groups can play a potential role for designing aggregation induced emission (AIE) active fluorescent probes.  相似文献   
15.
16.
Effect of the aqueous extract of fresh coriander (Coriandrum sativum) seeds has been studied on female fertility in rats. Parameters included effects on oestrus cycle, implantation, foetal loss, abortion, teratogenicity and serum progesterone levels on days 5, 12 and 20 of the pregnancy. The extract at doses of 250 and 500 mg/kg orally produced a dose-dependent significant anti-implantation effect, but failed to produce complete infertility. Treatment of animals during day-8 to day-12 and day-12 to day-20 of the pregnancy did not produce any significant abortifacient activity. There was no significant change in the weight and length of the foetuses delivered by rats treated with the extract and no abnormalities were seen in the organs of the offsprings. The extracts produced a significant decrease in serum progesterone levels on day-5 of pregnancy which may be responsible for the anti-implantation effect observed in this study.  相似文献   
17.
M Tariq  A M Ageel  N S Parmar 《Toxicon》1986,24(1):101-103
Administration of endotoxin, a lipopolysaccharide extracted from cell walls of gram negative bacteria, elicited alterations in various metabolic parameters and in the electrocardiogram of rats. Cardiac glycogen and serum glucose were decreased, while serum pyruvate and acid phosphatase levels were increased. There was initial tachycardia followed by significant bradycardia and elevation of the ST segment in the animals with shock. Erythrocyte count, haemoglobin and haematocrit were not changed after shock. Treatment with naloxone caused significant decreases in the metabolic and electrocardiographic changes induced by endotoxin.  相似文献   
18.
19.
Patients with impacted esophageal foreign bodies usually present with gastrointestinal and rarely with respiratory symptoms. Impacted esophageal foreign bodies may be identified by radiologic studies. Ingested radiolucent foreign bodies may be more difficult to diagnose, especially if the patient presents with minimal symptoms. We report a rare case of a child who presented with stridor and obstructive sleep apnea. The cause of respiratory symptoms was thought to be due to enlarged tonsils and adenoids, and the patient was scheduled for tonsillectomy and adenoidectomy. On re-evaluation by the surgeon on the day of surgery, the procedure was changed to diagnostic microlaryngoscopy and bronchoscopy to rule out any other cause. The patient’s respiratory symptoms were resolved when an incidental discovery and retrieval of the radiolucent esophageal foreign body was made. The diagnosis of radiolucent esophageal foreign body can be difficult and can be easily missed without reasonable clinical suspicion.  相似文献   
20.
OBJECT: The authors report the management protocol and successful outcomes in 6 patients with dissecting aneurysms of the posterior inferior cerebellar artery (PICA). METHODS: Medical records and neuroimaging studies of 6 patients who underwent surgical treatment of dissecting PICA aneurysms were reviewed. The mean follow-up duration was 1.8 years. No patient was lost to follow-up review. RESULTS: Four patients presented with acute subarachnoid hemorrhage and 2 with PICA ischemia. All patients underwent surgery, which entailed proximal occlusion with distal revascularization in 3 cases and circumferential wrap/clip reconstruction in 3 cases. The revascularization techniques used were occipital artery-PICA bypass and PICA-PICA anastomosis. Delayed follow-up angiography was performed in all cases. In patients treated with proximal occlusion, delayed angiography showed minimal retrograde opacification of the dissected segments. The 3 patients treated with wrap/clip reconstruction showed unexpectedly significant normalization of their lesions on angiographic studies. Outcome was good in all cases. CONCLUSIONS: Dissecting PICA aneurysms are rare lesions with an apparent propensity for bleeding. Individualized management including distal revascularization with PICA sacrifice or circumferential wrap/clip reconstruction to reinforce the dissected segment produced good outcomes. Patients treated with aneurysm wrapping may show dramatic angiographic improvement of the dissected segment.  相似文献   
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