Resin corrosion cast (Mercox) in experimental evaluation of small vessel anastomosis

This study focuses on obtaining more information about the site of anastomosis, with three-dimensional examination using methylmethacrylate resin (Mercox) corrosion casts. Seventy microvascular anastomoses were performed in Wistar albino rats, divided into two groups before sacrifice. In Group 1 (35), Mercox was injected into the vessels, whereas in Group 2 (35), the tissues were prepared without injecting Mercox. Both groups were compared under the scanning electron microscope (SEM). The SEM preparation in Group 1 was simple, easy, and artifacts were significantly minimized. The anastomotic site could be well appreciated in three-dimensional views. Clear negative imprints of the endothelial surface were achieved without any breakage in the Mercox corrosion cast, and it can be reliably used in the evaluation of small vessel anastomosis.     

In vitro combination treatment with perifosine and UCN-01 demonstrates synergism against prostate (PC-3) and lung (A549) epithelial adenocarcinoma cell lines.

PURPOSE: Antineoplastic agents often achieve antitumor activity at the expense of close to unacceptable toxicity. One potential avenue to improve therapeutic index might combine agents targeting distinct components of the same growth regulatory pathway. This might lead to more complete modulation of the target pathway at concentrations lower than those associated with limiting adventitious toxicities from either agent alone. The protein kinase antagonist UCN-01 is currently used in Phase I/II trials and has recently been demonstrated to inhibit potently PDK1. We have recently documented that the alkylphospholipid perifosine potently also inhibits Akt kinase (PKB) activation by interfering with membrane localization of Akt. This leads to the hypothesis that these two agents might act synergistically through distinct mechanisms in the PI3K/Akt proliferation and survival-related signaling pathway. EXPERIMENTAL DESIGN: The synergistic effects of UCN-01 and perifosine, on two cell lines (A-549 and PC-3), were examined using various long-term in vitro assays for cell growth, cell cycle distribution, clonogenicity, survival morphology, and apoptosis. Along with Western blotting experiments were performed to determine whether this synergistic combination of two drugs has significant effect on their downstream targets and on biochemical markers of apoptosis. RESULTS: After 72 h, perifosine at concentrations of 1.5 and 10 microM UCN-01 at 40 and 250 nM did not significantly affect the growth of PC-3 and A459 cells, respectively. However, in combination at the same respective individual concentrations (1.5 microM and 40 nM of perifosine and UCN-01, respectively, in PC-3 cells and 10 microM perifosine and 0.25 microM UCN-01 in the somewhat more resistant A549 cells), virtually complete growth inhibition of both the cell lines resulted. Supra-additive inhibition of growth was also demonstrated in independent clonogenic assays. Mechanistic studies in cell culture models suggest enhanced depletion of the S-phase population in cells treated by the combination. This correlated with enhanced inactivation of Akt along with activation of caspases 3 and 9 and poly(ADP-ribose) polymerase cleavage. Evidence of synergy was formally demonstrated and occurred across a wide range of drug concentrations and was largely independent of the order or sequence of drug addition. CONCLUSIONS: As the concentrations of UCN-01 and perifosine causing synergistic inhibition of cell growth are clinically achievable without prominent toxicity, these data support the development of clinical studies with this combination.     

Endophytic fungi harbored in Cannabis sativa L.: diversity and potential as biocontrol agents against host plant-specific phytopathogens

The objective of the present work was isolation, phylogenetic characterization, and assessment of biocontrol potential of endophytic fungi harbored in various tissues (leaves, twigs, and apical and lateral buds) of the medicinal plant, Cannabis sativa L. A total of 30 different fungal endophytes were isolated from all the plant tissues which were authenticated by molecular identification based on rDNA ITS sequence analysis (ITS1, 5.8S and ITS2 regions). The Menhinick’s index revealed that the buds were immensely rich in fungal species, and Camargo’s index showed the highest tissue-specific fungal dominance for the twigs. The most dominant species was Penicillium copticola that could be isolated from the twigs, leaves, and apical and lateral buds. A detailed calculation of Fisher’s log series index, Shannon diversity index, Simpson’s index, Simpson’s diversity index, and Margalef’s richness revealed moderate overall biodiversity of C. sativa endophytes distributed among its tissues. The fungal endophytes were challenged by two host phytopathogens, Botrytis cinerea and Trichothecium roseum, devising a dual culture antagonistic assay on five different media. We observed 11 distinct types of pathogen inhibition encompassing a variable degree of antagonism (%) on changing the media. This revealed the potential chemodiversity of the isolated fungal endophytes not only as promising resources of biocontrol agents against the known and emerging phytopathogens of Cannabis plants, but also as sustainable resources of biologically active and defensive secondary metabolites.     

Trichoderma harzianum ThU and Its Metabolites Underscore Alteration in Essential Oils of Ocimum basilicum and Ocimum sanctum

Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Ocimum, an important commercial aromatic crop, is well known for the industrially acclaimed essential oil. In...     

Monitoring and management of antituberculosis drug induced hepatotoxicity

BACKGROUND: Hepatotoxicity to antituberculosis therapy (ATT) poses a major challenge. This often results in inadequate therapy. The risk of fulminant hepatic failure and mortality is high once icteric hepatitis develops. There is no consensus on monitoring protocols and for the reintroduction of ATT. METHODS: All patients (from the Department of Internal Medicine and Gastroenterology, Jagjivanram Hospital and the Department of Gastroenterology, Bombay Hospital, Mumbai, India) with a diagnosis of tuberculosis, who were to receive ATT during the study period, were included in the present study for prospective periodic laboratory monitoring for the development of hepatotoxicity. Those patients who developed hepatotoxicity formed Group A (n = 21), whereas those who did not develop hepatotoxicity were included in Group C (n = 179). For the purpose of comparison with Group A, all the patients who presented directly with ATT induced hepatotoxicity during the study period were categorized as Group B (n = 24). Group A and B were further studied after normalization of liver functions for sequential reintroduction with therapeutic doses at a weekly interval. RESULTS: In Group A, 66.6% (14 patients) of the patients were diagnosed in the asymptomatic period. Seven patients had symptomatic hepatitis, but none had icteric illness. There were no mortalities in Group A. In contrast, all the patients in Group B had symptomatic hepatitis (75% icteric hepatitis). There was a mortality rate of 16.6% (four patients). Of the 41 patients from Groups A and B who survived, reintroduction was successful in 38/39 (97.4%). In the remaining two patients who were in Group B, reintroduction was not attempted because of decompensated liver disease. CONCLUSIONS: Periodic laboratory monitoring is important in detecting hepatotoxicity at an early stage, thereby preventing mortality. Sequential reintroduction is often successful.     

Acyldepsipeptide activated ClpP1P2 macromolecule of Leptospira,an ideal Achilles’ heel to hamper the cell survival and deregulate ClpP proteolytic activity

Antibiotic acyldepsipeptide (ADEP) targets the bacterial ClpP serine protease and can inhibit the growth of numerous bacterial species by activating/dysregulating the protease activity within the cell. The spirochete Leptospira interrogans harbors two ClpP isoforms (LepClpP1 and LepClpP2). Supplementation of ADEP in the Leptospira growth medium resulted in the inhibition of bacterial growth. The ADEP mediated activation of the LepClpP mixture was dependent on the time allowed for the self-assembly of LepClpP1 and LepClpP2. The dynamic light scattering of the LepClpP mixture in the presence of the ADEP indicated a conformational transformation of the LepClpP machinery. Serine 98, a catalytic triad residue of the LepClpP1 in the LepClpP1P2 heterocomplex, was critical for the ADEP mediated activation. The computational prototype of the LepClpP1P2 structure suggested that the hydrophobic pockets wherein the ADEPs or the physiological chaperone ClpX predominantly dock are exclusively present in the LepClpP2 heptamer. Using the ADEP as a tool, this investigation provides an insight into the molecular function of the LepClpP1P2 in a coalition with its ATPase chaperone LepClpX. The shreds of the evidence illustrated in this investigation verify that ADEP1 possesses the ability to control the LepClpP system in an unconventional approach than the other organisms.     

Imaging the pediatric retina: An overview

Recent decade has seen a shift in the causes of childhood blinding diseases from anterior segment to retinal disease in both developed and developing countries. The common retinal disorders are retinopathy of prematurity and vitreoretinal infections in neonates, congenital anomalies in infants, and vascular retinopathies including type 1 diabetes, tumors, and inherited retinal diseases in children (up to 12 years). Retinal imaging helps in diagnosis, management, follow up and prognostication in all these disorders. These imaging modalities include fundus photography, fluorescein angiography, ultrasonography, retinal vascular and structural studies, and electrodiagnosis. Over the decades there has been tremendous advances both in design (compact, multifunctional, tele-consult capable) and technology (wide- and ultra-wide field and noninvasive retinal angiography). These new advances have application in most of the pediatric retinal diseases though at most times the designs of new devices have remained confined to use in adults. Poor patient cooperation and insufficient attention span in children demand careful crafting of the devices. The newer attempts of hand-held retinal diagnostic devices are welcome additions in this direction. While much has been done, there is still much to do in the coming years. One of the compelling and immediate needs is the pediatric version of optical coherence tomography angiography. These needs and demands would increase many folds in future. A sound policy could be the simultaneous development of adult and pediatric version of all ophthalmic diagnostic devices, coupled with capacity building of trained medical personnel.