Bacterial Endophthalmitis

Endophthalmitis is an ocular inflammation involving vitreous cavity along with the retinal and uveal components of the eye mostly due to infectious agent. The source of infection could be exogenous or endogenous. Exogenous endophthalmitis results from direct inoculation as a complication of ocular surgery, foreign bodies or penetrating ocular trauma, while endogenous endophthalmitis results from haematogenous spread of organisms from a distant source of infection. Endophthalmitis often results in partial or complete loss of vision despite aggressive therapeutic and surgical intervention and hence it is considered as a medical emergency. Diagnosis of infectious agent is critical in the management of these agents. Intravitreal antimicrobial therapy along with anti-inflammatory agents is the key ingredient for successful management of endophthalmitis, while surgical procedures like vitrectomy become necessary in severe endophthalmitis cases. This is a brief review regarding classification, etiological agents causing endophthalmitis, diagnosis and therapeutic challenges of endophthalmitis that will help in improving the visual outcome

Protein complex directs hemoglobin-to-hemozoin formation in Plasmodium falciparum

Malaria parasites use hemoglobin (Hb) as a major nutrient source in the intraerythrocytic stage, during which heme is converted to hemozoin (Hz). The formation of Hz is essential for parasite survival, but to date, the underlying mechanisms of Hb degradation and Hz formation are poorly understood. We report the presence of a ∼200-kDa protein complex in the food vacuole that is required for Hb degradation and Hz formation. This complex contains several parasite proteins, including falcipain 2/2', plasmepsin II, plasmepsin IV, histo aspartic protease, and heme detoxification protein. The association of these proteins is evident from coimmunoprecipitation followed by mass spectrometry, coelution from a gel filtration column, cosedimentation on a glycerol gradient, and in vitro protein interaction analyses. To functionally characterize this complex, we developed an in vitro assay using two of the proteins present in the complex. Our results show that falcipain 2 and heme detoxification protein associate with each other to efficiently convert Hb to Hz. We also used this in vitro assay to elucidate the modes of action of chloroquine and artemisinin. Our results reveal that both chloroquine and artemisinin act during the heme polymerization step, and chloroquine also acts at the Hb degradation step. These results may have important implications in the development of previously undefined antimalarials

99mTc-DMSA (V) in Evaluation of Osteosarcoma: Comparative Studies with 18F-FDG PET/CT in Detection of Primary and Malignant Lesions

To evaluate the role of 99mTc-DMSA (V) and [18F]FDG PET-CT in management of patients with osteosarcoma, 22 patients were included in our study. All patients underwent both 99mTc-DMSA (V) and whole-body [18F]FDG PET-CT scans within an interval of 1 week. 555–740 MBq of 99mTc-DMSA (V) was injected i.v. the whole-body planar, SPECT images of primary site and chest were performed after 3-4 hours. [18F]FDG PET-CT images were obtained 60 minutes after i.v. injection of 370 MBq of F-18 FDG. Both FDG PET-CT (mean SUVmax = 7.1) and DMSA (V) scans showed abnormal uptake at primary site in all the 22 patients (100% sensitivity for both). Whole-body PET-CT detected metastasis in 11 pts (lung mets in 10 and lung + bone mets in 1 patient). Whole-body planar DMSA (V) and SPECT detected bone metastasis in one patient, lung mets in 7 patients and LN in 1 patient. HRCT of chest confirmed lung mets in 10 patients and inflammatory lesion in one patient. 7 patients positive for mets on DMSA (V) scan had higher uptake in lung lesions as compared to FDG uptake on PET-CT. Three patients who did not show any DMSA uptake had subcentimeter lung nodule. Resuts of both 99mTc-DMSA (V) (whole-body planar and SPECT imaging) and [18F]FDG PET-CT were comparable in evaluation of primary site lesions and metastatic lesions greater than 1 cm. Though 99mTc-DMSA (V) had higher uptake in the lesions as compared to [18F]FDG PET-CT, the only advantage [18F]FDG PET-CT had was that it could also detect subcentimeter lesions

Impact of fly ash content and fly ash transportation distance on embodied greenhouse gas emissions and water consumption in concrete

Background, aim and scope Fly ash, a by-product of coal-fired power stations, is substituted for Portland cement to improve the properties of concrete and reduce the embodied greenhouse gas (GHG) emissions. Much of the world's fly ash is currently disposed of as a waste product. While replacing some Portland cement with fly ash can reduce production costs and the embodied emissions of concrete, the relationship between fly ash content and embodied GHG emissions in concrete has not been quantified. The impact of fly ash content on embodied water is also unknown. Furthermore, it is not known whether a global trade in fly ash for use in concrete is feasible from a carbon balance perspective, or if transport over long distances would eliminate any CO(2) savings. This paper aims to quantify GHG emissions and water embodied in concrete (f'(c)= 32 MPa) as a function of fly ash content and to determine the critical fly ash transportation distance, beyond which use of fly ash in concrete increases embodied GHG emissions

Open Access Extracts from Acacia catechu suppress HIV-1 replication by inhibiting the activities of the viral

Background: Acacia catechu (Mimosa family) stem bark extracts have been used traditionally as a dietary supplement as well as a folk medicine given its reported anti-inflammatory, immunomodulatory, hepatoprotective, antioxidant, anti-microbial and anti-tumor activities. The present study was undertaken to evaluate the anti-HIV-1 activity of the extracts from stem bark of A. catechu. Methods: The aqueous and 50 % ethanolic extracts of A. catechu stem bark were prepared and 50 % ethanolic extract was further fractioned by successively partitioning with petroleum ether, chloroform and n-butanol. All the extracts and fractions were evaluated for cytotoxicity and anti-HIV-1 activity using different in vitro assays. The active n-butanol fraction was evaluated for its inhibition against HIV-1 reverse transcriptase, integrase, protease, pro-viral genome integration and viral Tat protein mediated transactivation. The effect of n-butanol fraction on the induction of pro-inflammatory cytokines secretion in Vk2/E6E7 cells and transepithelial resistance in Caco-2 and HEC-1A cells was investigated. Results: The aqueous and 50 % ethanolic extracts of A. catechu showed IC50 values of 1.8 ± 0.18 μg/ml and 3.6 ± 0.31 μg/ml, respectively in cell-free virus based assay using TZM-bl cells and HIV-1NL4.3 (X-4 tropic). In the above assay, n-butanol fraction exhibited anti-HIV-1 activity with an IC50 of 1.7 ± 0.12 μg/ml. The n-butanol fractio

Characterization of protective epitopes in a highly conserved Plasmodium falciparum antigenic protein containing repeats of acidic and basic residues

The delineation of putatively protective and immunogenic epitopes in vaccine candidate proteins constitutes a major research effort towards the development of an effective malaria vaccine. By virtue of its role in the formation of the immune clusters of merozoites, its location on the surface of merozoites, and its highly conserved nature both at the nucleotide sequence level and the amino acid sequence level, the antigen which contains repeats of acidic and basic residues (ABRA) of the human malaria parasite Plasmodium falciparum represents such an antigen. Based upon the predicted amino acid sequence of ABRA, we synthesized eight peptides, with six of these (AB-1 to AB-6) ranging from 12 to 18 residues covering the most hydrophilic regions of the protein, and two more peptides (AB-7 and AB-8) representing its repetitive sequences. We found that all eight constructs bound an appreciable amount of antibody in sera from a large proportion of P. falciparum malaria patients; two of these peptides (AB-1 and AB-3) also elicited a strong proliferation response in peripheral blood mononuclear cells from all 11 human subjects recovering from malaria. When used as carrier-free immunogens, six peptides induced a strong, boostable, immunoglobulin G-type antibody response in rabbits, indicating the presence of both B-cell determinants and T-helper-cell epitopes in these six constructs. These antibodies specifically cross-reacted with the parasite protein(s) in an immunoblot and in an immunofluorescence assay. In another immunoblot, rabbit antipeptide sera also recognized recombinant fragments of ABRA expressed in bacteria. More significantly, rabbit antibodies against two constructs (AB-1 and AB-5) inhibited the merozoite reinvasion of human erythrocytes in vitro up to ∼90%. These results favor further studies so as to determine possible inclusion of these two constructs in a multicomponent subunit vaccine against asexual blood stages of P. falciparum

Does I-131-MIBG underestimate skeletal disease burden in neuroblastoma?

Background: Controversy persists as to the need for both MIBG and bone scanning in routine evaluation of neuroblastoma. Aim: To compare the efficacy of I-131- metaiodobenzylguanidine (MIBG) scan against that of conventional Tc99m- methylene diphosphonate (MDP) bone scan for the detection of skeletal deposition of neuroblastoma. Methods and Material: The study included 57 patients (36 boys, 21 girls: age range 1-14 years) of neuroblastoma who underwent both bone scan with Tc99m-MDP and I-131-MIBG scan within 15 days of each other at presentation and during follow-up. Results: At presentation 11(19.2%) patients had evidence of skeletal metastases on MDP scan against 7 patients who showed bony secondaries on MIBG scan. Of the 7 patients, with positive MIBG and MDP scans, MDP scan detected 11 sites whereas MIBG scan detected 7 sites. On follow-up study, 3 patients with initial abnormal MDP scan but normal MIBG scan, developed skeletal metastases detectable on MIBG scan, whereas 3 of the 46 patients who had normal MDP and MIBG scan at presentation; developed skeletal metastases detectable on MDP scan. MIBG scan was concordant in 2 of them but was normal in the third patient. Conclusion: I-131-MIBG underestimates skeletal disease burden in neuroblastoma. Therefore, Tc99m-MDP bone scan should remain a part of routine assessment of patients with neuroblastoma