Pouteria campechiana leaf extract and its bioactive compound myricitrin are mosquitocidal against Aedes aegypti and Culex quinquefasciatus

Objective: To test the mosquitocidal potential of leaf extracts of Pouteria campechiana prepared with different solvents and elucidate the structure of an isolated mosquitocidal compound. Methods: The leaf extracts of Pouteria campechiana prepared with three solvents(petroleum benzene, ethyl acetate and acetone) and potential bioactive fractions were tested against various stages of Aedes aegypti and Culex quinquefasciatus by using the WHO protocols, and the chemical profile and its functional groups were identified by GC-MS and Fourier transmissioninfrared spectroscopy(FT-IR). The structure of bioactive compound was characterized by nuclear magnetic resonance(NMR) spectral technique. Results: The preliminary phytochemical results revealed the presence of alkaloids, amino acids, flavonoids, quinones, saponins, steroids, tannins, and terpenoids in the acetone extract. A significant toxic potential was observed in the acetone extract against both Aedes aegypti and Culex quinquefasciatus mosquitoes. The acetone extract exhibits remarkable larvicidal(LC_(50): 12.232 μg/mL and LC_(90): 63.970 μg/mL), pupicidal(LC_(50): 18.949 μg/mL and LC_(90): 167.669 μg/m L) and adulticidal(LC_(50): 20.689 μg/mL and LC_(90): 72.881 μg/mL) effects against Aedes aegypti. Furthermore, the same extract was subjected to isolation of bioactive compound by GCMS and FT-IR analysis. GC-MS results showed the presence of 5 major compounds, and octacosane(18.440%) was detected as the predominant compound. The FT-IR result of acetone extract demonstrated the presence of various functional groups like alkanes/alkynes, ester, aromatic and amides. The NMR spectrum results of isolated compound were well matched to glycoside linked flavonoids. Based on the chromatography and spectral techniques the isolate molecule was identified as myricitrin by FT-IR and nuclear magnetic resonance spectral data. Conclusion: The isolated compound myricitrin possesses a significant toxic effect in all stages of Aedes aegypti and Culex quinquefasciatus mosquito's with lowest LC_(50) and LC_(90) values.     

The effect of transport on the physiologic stability of neonates with ductal-dependent single-ventricle lesions

Objective: To compare the status of infants with hypoplastic left heart syndrome (HLHS) or pulmonary atresia-hypoplastic right heart (PA-HRH) before and following transport using the validated Transport Risk Index of Physiologic Stability (TRIPS) score.

Methods: In this retrospective review of infants with HLHS or PA-HRH transported to a Children’s Hospital by a pediatric transport team, an increase in TRIPS score (temperature, blood pressure, respiratory status, and response to stimuli) following transport was defined as deterioration. Statistical analyses included t-test (paired and independent), χ², and McNemar’s tests for comparisons between groups with and without deterioration and before and after transport.

Results: Our cohort [n?=?64; 39 (61%) HLHS and 25 (39%) PA-HRH] was predominantly female (61%), black (56%), and diagnosed antenatally (78%). Median transport time was 20 (10–30) min and age was?<12?h in 48 (75%) infants. TRIPS scores worsened after transport in 24 (37.5%) infants, due to temperature (n?=?10) or respiratory (n?=?7) dysregulation. Infants who deteriorated during transport had HLH more often (83 versus 48%) and lower pH [7.27 (0.12) versus 7.33 (0.07)]. HLH was significantly predictive of deterioration during transport [OR 5.60 (95% C.I. 1.18–26.62)].

Conclusions: The physiologic deterioration in a third of infants with single ventricle following short transports is intriguing and may have implications on their optimal place of birth.     

Supplement Timing of Cranberry Extract Plays a Key Role in Promoting Caenorhabditis elegans Healthspan

Consumption of nutraceuticals is a major and potent dietary intervention for delaying aging. As the timing of administration is critical for the efficacy of bioactive compounds in medicine, the effectiveness of nutraceuticals may also be dramatically affected by the timing of supplementation. Cranberry exact (CBE), rich in polyphenols, is consumed as a nutraceutical, and possesses anti-aging properties. Here, we examined the influence of timing on the beneficial effects of CBE supplementation in C. elegans. The prolongevity effect of CBE in different aged worms, young adults, middle-age adults, and aged adults, was determined. Early-start intervention with CBE prolonged the remaining lifespan of worms of different ages more robustly than late-start intervention. The effectiveness of CBE on stress responses and physiological behaviors in different aged worms was also investigated. The early-start intervention prominently promoted motility and resistance to heat shocks and V. cholera infection, especially in aged worms. Together, these findings suggest that the timing of CBE supplementation critically influences its beneficial effects on C. elegans lifespan and healthspan. It is of interest to further investigate whether the similar results would occur in humans.     

Prevalence and short-term mortality of acute-on-chronic liver failure: A national cohort study from the USA

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Pathophysiology,Diagnosis, and Management of Coronary No-Reflow Phenomenon

Coronary no-reflow phenomenon is a lethal mechanism of ongoing myocardial injury, following successful revascularization of an infarct-related coronary artery. Incidence of this phenomenon is high following percutaneous intervention, and is associated with adverse in-hospital and long-term outcomes. Several mechanisms such as ischemia-reperfusion injury and distal microthromboembolism in genetically susceptible patients and those with preexisting endothelial dysfunction have been implicated. However, the exact mechanism in humans is still poorly understood. Several investigative and treatment strategies within and outside the cardiac catheterization laboratory have been proposed, but have not uniformly shown success in reducing mortality or in preventing adverse left ventricular remodeling resulting from this condition. The aim of this article is to provide a brief and concise review of the current understanding of the pathophysiology, clinical predictors, and investigations and management of coronary no-reflow phenomenon.     

A 12-lipoxygenase product of arachidonate metabolism is involved in angiotensin action on renin release

Angiotensin II (AII) action is coupled to the hydrolysis of phospholipids resulting in the formation of arachidonic acid, the precursor of both prostaglandins, and hydroxyeicosatetraenoic acids (HETEs). Since 12-HETE is not only a major arachidonate lipoxygenase (LO) product in the kidney, but is also a potent inhibitor of renin release, we studied the role of AII on renin inhibition and 12-HETE formation using rat renal cortical slices and isolated juxtaglomerular-like cells. In both preparations, 12-HETE was produced in a basal state. AII significantly inhibited renin release (control 100 +/- 3%, AII (10(8) M) 79 + 4%, P less than 0.01) and stimulated 12-HETE formation in slices (control 106 +/- 6%, AII 10(-8) M 177 +/- 18%, P less than 0.01) and in an enriched juxtaglomular cell preparation (control 96 +/- 3%, AII 10(-8) M 130 +/- 6%, P less than 0.001). A specific cyclooxygenase blocker, meclofenomate, or 5-LO blocker, U60,257, did not alter basal or AII-induced renin inhibition or 12-HETE formation by slices. The LO blockers BW755c, at 10(-5) M, or baicalein, 10(-6) M, did not significantly alter basal renin or 12-HETE levels, but BW755c at 10(-4) M, significantly stimulated basal renin (131 +/- 4%) and decreased basal 12-HETE levels (72 +/- 5%). However, both BW755c and baicalein blunted AII-induced renin inhibition (AII, 10(-8) M 70 +/- 3%, AII + BW755c, 10(-5) M 85 +/- 4%, P less than 0.02, AII + baicalein, 10(-6) M, 90 +/- 4%, P less than 0.005) and AII mediated 12-HETE formation (AII, 10(-8) M 150 +/- 5%, AII + BW755c, 10(-5) M 117 +/- 8%, P less than 0.02, AII + baicalein, 10(-6) M 110 +/- 3%, P less than 0.005). These results suggest that AII inhibition of renin is not mediated by the cyclooxygenase or 5-LO pathway, but rather by the 12-LO pathway. These findings reveal a new action for 12-LO products which may play a pivotal role in stimulus secretion coupling of renin secretion.