Molecular Characterization of a Novel, Highly Protective Combination Monoclonal Antibody Therapy against Chikungunya Virus

Chikungunya virus (CHIKV) is an Aedes mosquito-transmitted alphavirus that causes epidemics of a debilitating, often chronic polyarthritis in humans. Over five million people in Africa and Asia have been infected since 2005, and an outbreak occurred recently in Italy demonstrating the potential for a global epidemic. A strong antibody response is elicited during infection and the aim of this thesis was to develop a better understanding of how the humoral immune response can control CHIKV infection. We identified 230 new anti-CHIKV monoclonal antibodies (MAbs) and tested their ability to inhibit infection of strains representing all three CHIKV genotypes (East/Central/South African, West African and Asian). We identified 36 of these MAbs that inhibit Chikungunya infection; almost half of them are potently neutralizing and have EC50 values of less than 15 ng/mL (0.1 nM) against CHIKV strains representing the three genotypes. Many of these MAbs exhibit cross-reactivity with a number of related alphaviruses including O\u27nyong\u27nyong, Ross River, Semliki Forest, Mayaro, Una, Getah, Bebaru, Middleburg, Barmah Forest, Sindbis and Venezuelan equine encephalitis viruses. Four of these neutralizing MAbs provided complete protection as prophylaxis in highly susceptible immunocompromised mice and mapped to distinct antigenic epitopes on the E1 and E2 structural proteins. To define functional epitopes, we selected for escape mutants in vitro for these four MAbs. We identified most of these escape mutants in the brains and leg muscle of mice dying despite lower dose prophylaxis or monotherapy. The most protective MAb was humanized, shown to block viral fusion, and require Fc effector function for optimal activity in vivo. In post-exposure therapeutic trials, administration of a single dose of a combination of two neutralizing MAbs targeting different domains of the E2 surface glycoprotein or targeting both the E1 and E2 glycoproteins limited the development of resistance and protected immunocompromised mice against disease when given even 24 to 36 hours before CHIKV-induced death. These studies provide some insight into the location of neutralizing epitopes of CHIKV and how selected pairs of highly neutralizing MAbs may be a promising treatment option for CHIKV infection in humans

Short-term X-ray Variability during Different Activity Phases of Blazars S5 0716+714 and PKS 2155-304

We explored the statistical properties of short-term X-ray variability using long-exposure {\it XMM-Newton} data during high X-ray variability phases of blazars S5 0716+714 and PKS 2155-304. In general, hardness ratio shows correlated variations with the source flux state (count rate), but in a few cases, mainly the bright phases, the trend is complex with correlation and anti-correlation both, indicating spectral evolution. Stationarity tests suggest the time series as non-stationarity or have trend stationarity. Except for one, none of the histograms fit resulted in a reduced-$\chi^2 \sim 1$ for a normal and log-normal profile but a normal profile is favored in general. On the contrary, the Anderson-Darling test favors lognormal with a test-statistic value lower for log-normal over normal for all the observations, even if out of significance limits. None of the IDs show linear RMS-flux relation. The contrary inferences from widely used different statistical methods indicate that a careful analysis is needed while the complex behavior of count rate with hardness ratio suggests spectral evolution over a few 10s of kilo-seconds during bright phases of the sources. In these cases, the spectrum extracted from whole observation may not be meaningful for spectral studies and certainly not a true representation of the spectral state of the source.Comment: 14 Pages, 4 figures, 2 Table

Soil Fertility under Grassland Compared to Other Land Uses in Acid Soil of Himachal Pradesh, India

In the last decades severe changes in land use occurred in tropical countries, due to increasing population and their demand for food resources. Forest land is rapidly converted into agriculture or pastureland which may cause significant changes in soil fertility. Land-use exerts significant effect on nutrient availability and may also influence secondary succession and biomass production (Lu et al., 2002). Nutrient cycling in agroforestry is in between natural forest ecosystems of the tropics and most of the agricultural systems with are ‘‘leaky’’ having higher nutrient losses. Research indicated that decline of soil organic matter may occur due to conversion of forest and grassland into agriculture (Ouattara et al., 2006). Tree growth is highly influenced by base cations (Ca, Mg, K, Na) concentration, cation exchange capacity, and concentrations of Al and Mn. Calcium and N are specifically important, as they are primary constituents of biomass and regulate cell function of many tree species. Base cations also help in alleviating the effects of Al toxicity in acid soil

Temperature and dissolved oxygen stratification in the lake Rudrasagar: Preliminary investigations

Temperature drives the major physico-chemical and biological actions in inland water bodies. The higher the water temperature, the greater the biogeochemical activity influenced by the environmental intrinsic and extrinsic parameters. Temperature also controls the dynamics of sustainability of various aquatic organisms that live in lakes and reservoirs, though higher life forms, such as fish, insects, zooplankton, phytoplankton, and other aquatic species all have a recommended temperature variety. The increase in water temperature due to the increase in atmospheric air temperature results in lake water column stratification and the dissolved oxygen level variation in aquatic systems are greatly affected. The vertical distributions of dissolved oxygen in the water column are highly dependent due to change in vertical temperature gradient. In the present paper, an effort has been made to investigate the impact of temperature stratification on dissolved oxygen variability in the Rudrasagar, a natural lake in western Tripura. The changes in dissolved oxygen distribution in this natural lake will give us an idea of regional lake health condition and will also establish the need of further large scale research concerning the development of a biophysical-coupled model.   Keywords: Thermal stratification, Dissolved Oxygen, Thermocline, Rudrasagar Lake, Hypolimnio

Izdvajanje, identifikacija i molekularne značajke mikoplazama izdvojenih iz koza u Gujaratu u Indiji.

A total of 358 samples [nasal discharges (215), lung tissue (6), pleural fluid (4), joint fluid (5), milk (60), preputial swabs (22), conjunctival swabs (16), ear swabs (5) and vaginal discharges (25)] were subjected for cultural isolation on MBHS-L and MBHS-A media. Of these, a total of 30 isolates (8.35 %) of Mycoplasma species, (20 from nasal discharges, 4 from lung tissue, 2 from pleural fluid, 3 from milk and 1 from joint fluid) were isolated and characterized biochemically and identified as M. mycoides subsp. capri and M. capricolum subsp. capricolum by PCR and PCR-RFLP. The isolates were identified as the Mycoplasma species by their cultural, morphological, biochemical characteristics and this was further confirmed by PCR and PCR-RFLP using different cluster, group and species specific primer pairs and by restriction enzyme respectively. This is a rare report on the isolation, identification and molecular characterization of goat Mycoplasma species in Western India. These studies have revealed a high prevalence of Mycoplasma species infection in Western India.Ukupno je 358 uzoraka različitog materijala koza bilo nacijepljeno na hranjive podloge MBHS-L and MBHS-A radi izdvajanja mikoplazama. Pretraženo je bilo 215 uzoraka nosnog iscjetka, šest uzoraka plućnog tkiva, četiri uzorka pleuralne tekućine, pet uzoraka zglobne tekućine, 60 uzoraka mlijeka, 22 uzorka prepucijskog ispirka, 16 uzoraka obriska očne spojnice, pet uzoraka obriska uške i 25 uzoraka vaginalnog iscjetka. Mikoplazme su bile izdvojene iz 30 (8,35%) uzoraka, od čega iz 20 uzoraka nosnog iscjetka, četiri uzorka plućnog tkiva, dva pleuralne tekućine, tri uzorka mlijeka i jednog uzorka zglobne tekućine. Izolati su bili identificirani kao M. mycoides subsp. capri i M. capricolum subsp. capricolum i to na osnovi kulturalnih, morfoloških i biokemijskih svojstava te dodatne potvrde lančanom reakcijom polimerazom i PCR-RFLP rabeći različite skupine specifičnih početnica i restrikcijskih enzima. Ovo je rijetko izvješće o izdvajanju, identifikaciji i molekularnim svojstvima mikoplazama u Zapadnoj Indiji, koje ujedno pokazuje da je na tom području velika učestalost mikoplazmalnih zaraza u koza

Temperature and dissolved oxygen stratification in the lake Rudrasagar: Preliminary investigations

Temperature drives the major physico-chemical and biological actions in inland water bodies. The higher the water temperature, the greater the biogeochemical activity influenced by the environmental intrinsic and extrinsic parameters. Temperature also controls the dynamics of sustainability of various aquatic organisms that live in lakes and reservoirs, though higher life forms, such as fish, insects, zooplankton, phytoplankton, and other aquatic species all have a recommended temperature variety. The increase in water temperature due to the increase in atmospheric air temperature results in lake water column stratification and the dissolved oxygen level variation in aquatic systems are greatly affected. The vertical distributions of dissolved oxygen in the water column are highly dependent due to change in vertical temperature gradient. In the present paper, an effort has been made to investigate the impact of temperature stratification on dissolved oxygen variability in the Rudrasagar, a natural lake in western Tripura. The changes in dissolved oxygen distribution in this natural lake will give us an idea of regional lake health condition and will also establish the need of further large scale research concerning the development of a biophysical-coupled model