Toxicity effect of Delonix elata (Yellow Gulmohr) and predatory efficiency of Copepod,Mesocyclops aspericornis for the control of dengue vector,Aedes aegypti

Objective

To evaluate the toxicity, predatory efficiency of Delonix elata (D. elata) and Mesocyclops aspericornis (M. aspericornis) against dengue vector, Aedes aegypti (Ae. aegypti).

Methods

A mosquitocidal bioassay was conducted at different concentration of plant extract followed by WHO standard method. The probit analysis of each tested concentration and control were observed by using software SPSS 11 version package. The each tested concentration variable was assessed by DMRT method. The predatory efficiency of copepod was followed by Deo et al., 1988. The predator, M. aspericornis was observed for mortality, abnormalities, survival and swimming activity after 24 h treatment of plant and also predation on the mosquito larvae were observed.

Results

D. elata were tested for biological activity against the larvae, and pupae of Ae. aegypti. Significant mortality effects were observed in each life stage. The percentage of mortality was 100% in first and second instars whereas 96%, 92% in third and fourth instars. Fitted probit-mortality curves for larvae indicated the median and 90% lethal concentrations of D. elata for instars 1-4 to be 4.91 (8.13), 5.16 (8.44), 5.95 (7.76) and 6.87 (11.23), respectively. The results indicate that leaf extract exhibits significant biological activity against life stages. The present study revealed that D. elata is potentially important in the control of Ae. aegypti. Similar studies were conducted for predatory efficiency of Copepod, M. aspericornis against mosquito vector Ae. Aegypti. This study reported that the predatory copepod fed on 39% and 25% in I and III instar larvae of mosquito and in combined treatment of D. elata and copepod maximum control of mosquito larval states and at 83%, 80%, 75% and 53% in I, II, III and IV instars, respectively.

Conclusions

The combined action of plant extract and predatory copepod to effectively control mosquito population and reduce the dengue transmitting diseases.     

Shifting transition states in the unfolding of a large ankyrin repeat protein

The 33-amino-acid ankyrin motif comprises a beta-turn followed by two anti-parallel alpha-helices and a loop and tandem arrays of the motif pack in a linear fashion to produce elongated structures characterized by short-range interactions. In this article we use site-directed mutagenesis to investigate the kinetic unfolding mechanism of D34, a 426-residue, 12-ankyrin repeat fragment of the protein ankyrinR. The data are consistent with a model in which the N-terminal half of the protein unfolds first by unraveling progressively from the start of the polypeptide chain to form an intermediate; in the next step, the C-terminal half of the protein unfolds via two pathways whose transition states have either the early or the late C-terminal ankyrin repeats folded. We conclude that the two halves of the protein unfold by different mechanisms because the N-terminal moiety folds and unfolds in the context of a folded C-terminal moiety, which therefore acts as a "seed" and confers a unique directionality on the process, whereas the C-terminal moiety folds and unfolds in the context of an unfolded N-terminal moiety and therefore behaves like a single-domain ankyrin repeat protein, having a high degree of symmetry and consequently more than one unfolding pathway accessible to it.     

Comorbid depression in obstructive sleep apnea: an under-recognized association

Background

Obstructive sleep apnea (OSA) and depression may coexist in the same patient. This article aims to review the link between OSA and comorbid depression and critically evaluate the results of studies that assessed the correlation between OSA and depression, the impact of OSA treatment on comorbid depression, and the impact of comorbid depression on continuous positive airway pressure (CPAP) adherence.

Methods

An integrative review was conducted on English language studies and reports that assessed the relationship between OSA and depression. Studies were identified by searching PubMed, Web of Science and Google Scholar databases, and reference lists of included studies.

Results

Generally, cross-sectional studies show a higher prevalence of depression among OSA patients with both community and sleep disorder clinic samples. Nevertheless, the relationship between OSA and depression is complicated by the fact that the disorders have overlapping symptoms. Longitudinal studies demonstrate an increased risk of developing depression among people with OSA, as well as an association between OSA severity and the likelihood of developing depression. On the other hand, studies assessing the impact of CPAP therapy on depression among OSA patients report conflicting results. Therefore, it is essential to consider how the disorders affect one another and to understand the clinical consequences of treating each disorder in isolation.

Conclusion

Depression is prevalent among patients with OSA both in the community and in sleep disorder clinics. Clinicians in general should be aware of this significant association and should aim to treat both disorders.

     

Is cardiac MRI an effective test for arrhythmogenic right ventricular cardiomyopathy diagnosis?

AIM:To evaluate the referrals with suspected arrhythmogenic right ventricular cardiomyopathy(ARVC)and compare cardiac MR(cMR)findings against clinical diagnosis.METHODS:A retrospective analysis of 114(age range16 to 83,males 55%and females 45%)patients referred for cMR with a suspected diagnosis of ARVC between May 2006 and February 2010 was performed after obtaining institutional approval for service evaluation.Reasons for referral including clinical symptoms and family history of sudden death,electrocardiogram and echo abnormalities,cMR findings,final clinical diagnosis and information about clinical management were obtained.The results of cMR were classified as major,minor,non-specific or negative depending on both functional and tissue characterisation and the cMR results were compared against the final clinical diagnosis.RESULTS:The most common reasons for referral included arrhythmias(30%)and a family history of sudden death(20%).Of the total cohort of 114 patients:4 patients(4%)had major cMR findings for ARVC,13patients(11%)had minor cMR findings,2 patients had non-specific cMR findings relating to the right ventricle and 95 patients had a negative cMR.Of the 4 patients who had major cMR findings,3(75%)had a positive clinical diagnosis.In contrast,of the 13 patients who had minor cMR findings,only 2(15%)had a positive clinical diagnosis.Out of the 95 negative patients,clinical details were available for 81 patients and none of them had ARVC.Excluding the 14 patients with no clinical data and final diagnosis,the sensitivity of the test was 100%,specificity 87%,positive predictive value29%and the negative predictive value 100%.CONCLUSION:CMR is a useful tool for ARVC evaluation because of the high negative predictive value as the outcome has a significant impact on the clinical decision-making.     

Rathke's cleft cyst--an uncommon cause of headache in a young boy

Developmental disorders of the pituitary can present like a mass lesion in the region of the pituitary and produce pressure effects. Rathke's cleft cyst is one such developmental disorder of the pituitary which presents in early life producing pressure effects namely visual disturbances due to its proximity to optic chiasma, headache, and hormonal imbalance due to pituitary malfunction. In this case report a 19 years boy presented with symptoms of headache and gradual loss of vision over one year period. Neuro-imaging study demonstrated a cystic lesion in the region of the pituitary. Trans-sphenoidal hypophysectomy was performed. Histopathology of the biopsied material was suggestive of Rathke's cleft cyst. Following surgery the boy had a good visual recovery. So early diagnosis and removal of a Rathke's cleft cyst has a good prognosis as compared to a craniopharyngioma which is a very close differential diagnosis.     

Corrosion behavior and biocompatibility of nanostructured TiO2 film on Ti6Al4V

The corrosion behavior and cell adhesion property of nanostructured TiO2 films deposited electrolytically on Ti6Al4V were examined in the present in vitro study. The nanostructured TiO2 film deposition on Ti6Al4V was achieved via peroxoprecursors. SEM micrographs exhibit the formation of amorphous and crystallite TiO2 nanoparticles on Ti6Al4V before and after being annealed at 500 degrees C. Corrosion behavior of TiO2-deposited and uncoated Ti6Al4V was evaluated in freely aerated Hank's solution at 37 degrees C by the measurement and analysis of open-circuit potential variation with time, Tafel plots, and electrochemical impedance spectroscopy. The electrochemical results indicated that nano-TiO2 coated Ti6Al4V showed a better corrosion resistance in simulated biofluid than uncoated Ti6Al4V. Rat bone cells and human aortic smooth muscle cells were grown on these substrates to study the cellular responses in vitro. The SEM images revealed enhanced cell adhesion, cell spreading, and proliferation on nano-TiO2 coated Ti6Al4V compared to those grown on uncoated substrates for both cell lines. These results suggested that nanotopography produced by deposition of nanostructured TiO2 onto Ti alloy surfaces might enhance corrosion resistance, biocompatibility, and cell integration for implants made of Ti alloys.