Nano-compositional imaging of the lanthanum silicide system at THz wavelengths

Terahertz scattering-type scanning near-field optical microscopy (THz-sSNOM) provides a noninvasive way to probe the low frequency conductivity of materials and to characterize material compositions at the nanoscale. However, the potential capability of atomic compositional analysis with THz nanoscopy remains largely unexplored. Here, we perform THz near-field imaging and spectroscopy on a model rare-earth alloy of lanthanum silicide (La-Si) which is known to exhibit diverse compositional and structural phases. We identify subwavelength spatial variations in conductivity that is manifested as alloy microstructures down to much less than 1 μm in size and is remarkably distinct from the surface topography of the material. Signal contrasts from the near-field scattering responses enable mapping the local silicon/lanthanum content differences. These observations demonstrate that THz-sSNOM offers a new avenue to investigate the compositional heterogeneity of material phases and their related nanoscale electrical as well as optical properties.

Blood meals from 'dead-end' vertebrate hosts enhance transmission potential of malaria-infected mosquitoes

Ingestion of an additional blood meal(s) by a hematophagic insect can accelerate development of several vector-borne parasites and pathogens. Most studies, however, offer blood from the same vertebrate host species as the original challenge (for e.g., human for primary and additional blood meals). Here, we show a second blood meal from bovine and canine hosts can also enhance sporozoite migration in Anopheles stephensi mosquitoes infected with the human- and rodent-restricted Plasmodium falciparum and P. berghei, respectively. The extrinsic incubation period (time to sporozoite appearance in salivary glands) showed more consistent reductions with blood from human and bovine donors than canine blood, although the latter's effect may be confounded by the toxicity, albeit non-specific, associated with the anticoagulant used to collect whole blood from donors. The complex patterns of enhancement highlight the limitations of a laboratory system but are nonetheless reminiscent of parasite host-specificity and mosquito adaptations, and the genetic predisposition of An. stephensi for bovine blood. We suggest that in natural settings, a blood meal from any vertebrate host could accentuate the risk of human infections by P. falciparum: targeting vectors that also feed on animals, via endectocides for instance, may reduce the number of malaria-infected mosquitoes and thus directly lower residual transmission. Since endectocides also benefit animal health, our results underscore the utility of the One Health framework, which postulates that human health and well-being is interconnected with that of animals. We posit this framework will be further validated if our observations also apply to other vector-borne diseases which together are responsible for some of the highest rates of morbidity and mortality in socio-economically disadvantaged populations.

Comparative evaluation of native top feeds of western Himalayas for utilization as goat's ration in mash and block form

The current research was undertaken to scrutinize the effect of leaf meal mixture as concentrate mixture in the ration of goats. Leaf meal mixture (LMM) was prepared using equal quantities of ten top-foliages namely Acacia nilotica, Celtis australis, Ficus palmata, Ficus religiosa, Grewia optiva, Melia azadarach, Morus alba, Quercus incana, Salix alba and Zizyphus jujube obtained from district Poonch of Jammu region in western Himalayas. The LMM prepared was substituted for 15% in the concentrate mixture being fed to the goats. The study constituted of two trials. Concentrate mixture offered to the animals was in mash and multi-nutrient block in first and second trial respectively. A total of twelve non-descript, adult male goats were selected for each trial. Goats of 0-14 months age (27.71 ± 2.96 kg live body weight) of for first trial while goats of 12-16 months age (27.02 ± 2.93 kg live weight) for second trial were divided into control and treatment groups as per randomized block design and fed ad-lib wheat straw and concentrate mixture @ (20 g/kgW0.75). No significant variation was observed (p > 0.05) in body weight, feed and DM intake among all groups in both trials. Comparable intake as well as digestibility of various nutrients like DM, OM, CP, EE, CF, NFE, NDF, ADF and TDN were found between the two groups during individual trials. There was a positive nitrogen, calcium and phosphorus balance among all experimental animals in both the trials. Serum enzymes ALT, AST and haemato-biochemical parameters like total protein, albumin, globulin, albumin: globulin and blood urea nitrogen (BUN) showed no significant differences during both trials in all groups, being within normal physiological levels. However, haemoglobin concentration was significantly higher (P < 0.05) in treatment group with respect to the control group in first trial. On the basis of current results, it can be established that leaf meal mixture can successfully be used to replace concentrate mixture up to 15% in the ration of goats without expecting any adverse impacts on their growth and overall health.

Gastrointestinal helminths increase Bordetella bronchiseptica shedding and host variation in supershedding

Co-infected hosts, individuals that carry more than one infectious agent at any one time, have been suggested to facilitate pathogen transmission, including the emergence of supershedding events. However, how the host immune response mediates the interactions between co-infecting pathogens and how these affect the dynamics of shedding remains largely unclear. We used laboratory experiments and a modeling approach to examine temporal changes in the shedding of the respiratory bacterium Bordetella bronchiseptica in rabbits with one or two gastrointestinal helminth species. Experimental data showed that rabbits co-infected with one or both helminths shed significantly more B. bronchiseptica, by direct contact with an agar petri dish, than rabbits with bacteria alone. Co-infected hosts generated supershedding events of higher intensity and more frequently than hosts with no helminths. To explain this variation in shedding an infection-immune model was developed and fitted to rabbits of each group. Simulations suggested that differences in the magnitude and duration of shedding could be explained by the effect of the two helminths on the relative contribution of neutrophils and specific IgA and IgG to B. bronchiseptica neutralization in the respiratory tract. However, the interactions between infection and immune response at the scale of analysis that we used could not capture the rapid variation in the intensity of shedding of every rabbit. We suggest that fast and local changes at the level of respiratory tissue probably played a more important role. This study indicates that co-infected hosts are important source of variation in shedding, and provides a quantitative explanation into the role of helminths to the dynamics of respiratory bacterial infections.

Streamlining sporozoite isolation from mosquitoes by leveraging the dynamics of migration to the salivary glands

Background

Sporozoites isolated from the salivary glands of Plasmodium-infected mosquitoes are a prerequisite for several basic and pre-clinical applications. Although salivary glands are pooled to maximize sporozoite recovery, insufficient yields pose logistical and analytical hurdles; thus, predicting yields prior to isolation would be valuable. Preceding oocyst densities in the midgut is an obvious candidate. However, it is unclear whether current understanding of its relationship with sporozoite densities can be used to maximize yields, or whether it can capture the potential density-dependence in rates of sporozoite invasion of the salivary glands.

Methods

This study presents a retrospective analysis of Anopheles stephensi mosquitoes infected with two strains of the rodent-specific Plasmodium berghei. Mean oocyst densities were estimated in the midguts earlier in the infection (11–15 days post-blood meal), with sporozoites pooled from the salivary glands later in the infection (17–29 days). Generalized linear mixed effects models were used to determine if (1) mean oocyst densities can predict sporozoite yields from pooled salivary glands, (2) whether these densities can capture differences in rates of sporozoite invasion of salivary glands, and (3), if the interaction between oocyst densities and time could be leveraged to boost overall yields.

Results

The non-linear effect of mean oocyst densities confirmed the role of density-dependent constraints in limiting yields beyond certain oocyst densities. Irrespective of oocyst densities however, the continued invasion of salivary glands by the sporozoites boosted recoveries over time (17–29 days post-blood meal) for either parasite strain.

Conclusions

Sporozoite invasion of the salivary glands over time can be leveraged to maximize yields for P. berghei. In general, however, invasion of the salivary glands over time is a critical fitness determinant for all Plasmodium species (extrinsic incubation period, EIP). Thus, delaying sporozoite collection could, in principle, substantially reduce dissection effort for any parasite within the genus, with the results also alluding to the potential for changes in sporozoites densities over time to modify infectivity for the next host.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12936-022-04270-y.

Spent marigold flower meal as an alternate feed for goats

This research trial is aimed to study the nutritional qualities and significance of feeding spent marigold flower meal (SMFM) in goats. SMFM and diet containing iso-nitrogenous concentrate mixture with different levels of spent marigold flower meal (0-30%) were studied for in vitro degradation. Depending upon the in vitro results, concentrate mixture containing 15% level of SMFM was selected for in vivo trial. In vivo studies were conducted for a period of 60 days, and 12 local, non-descript, adult male goats (10-14 months age; 31.09 ± 2.91 kg body weight) were randomly assigned to two groups and were fed on ad libitum wheat straw with either conventional (control) or SMFM containing concentrate mixture (treatment). Results of the study showed that there was no variation in body weight of the goats between periods and between groups. DM and OM intake along with their digestibility were similar among the two groups. The digestibility of all other nutrients was comparable between the two groups. Nitrogen, calcium and phosphorus balance were positive in both the groups without any significant disparity. Moreover, experimental goats did not differ in biochemical parameters, without any significant difference between periods and dietary treatments except AST level which was significantly higher (P > 0.05) in treatment group. So, this study successfully demonstrates that SMFM could be incorporated in the concentrate mixture, up to 15% without any discernable difference in the performance of goats.

Sex, age, and parental harmonic convergence behavior affect the immune performance of Aedes aegypti offspring

Harmonic convergence is a potential cue, female mosquitoes use to choose male mates. However, very little is known about the benefits this choice confers to offspring performance. Using Aedes aegypti (an important vector of human disease), we investigated whether offspring of converging parental pairs showed differences in immune competence compared to offspring derived from non-converging parental pairs. Here we show that harmonic convergence, along with several other interacting factors (sex, age, reproductive, and physiological status), significantly shaped offspring immune responses (melanization and response to a bacterial challenge). Harmonic convergence had a stronger effect on the immune response of male offspring than on female offspring. Further, female offspring from converging parental pairs disseminated dengue virus more quickly than offspring derived from non-converging parental pairs. Our results provide insight into a wide range of selective pressures shaping mosquito immune function and could have important implications for disease transmission and control.

Magnetic ground states of Ce3TiSb5, Pr3TiSb5and Nd3TiSb5determined by neutron powder diffraction and magnetic measurements

TheR₃TiSb₅ternary compounds, withRa light rare earth (La to Sm) have been reported to crystallize with the anti-Hf₅CuSn₃-type hexagonal structure (Pearson's symbolhP18; space-groupP6₃/mcm, N. 193). An early article that reported possible superconductivity in some of these intermetallic phases (namely those withR= La, Ce, and Nd) caught our attention. In this work, we have now refined the crystal structure of theR₃TiSb₅compounds withR= Ce, Pr and Nd by Rietveld methods using high-resolution neutron powder diffraction data. The magnetic ground states of these intermetallics have been investigated by low-temperature magnetization and high-intensity neutron diffraction. We find two different magnetic transitions corresponding to two related magnetic structures atT_N1= 4.8 K (k₁= [0, 1/2, 1/8]) andT_N2= 3.4 K (k₂= [0, 0, 1/8]), respectively for Ce₃TiSb₅. However, the magnetic ordering appears to occur following a peculiar hysteresis: thek₂-type magnetic structure develops only after thek₁-type phase fraction has first slowly ordered with time and the size of the ordered Ce³⁺magnetic moment has become large enough to induce the second magnetic transition. AtT= 1.5 K the maximum amplitude of the Ce moment in the coexisting phases amounts toμ_Ce= 2.15 μ_B. For Nd₃TiSb₅an antiferromagnetic ordering belowT_N= 5.2 K into a relatively simpler commensurate magnetic structure with a magnetic moment ofμ_Nd= 2.14(3)μ_Band magnetic propagation vector ofk= [0, 0, 0], was determined. No evidence of superconductivity has been found in Nd₃TiSb₅. Finally, Pr₃TiSb₅does not show any ordering down to 1.5 K in neutron diffraction while an antiferromagnetic ground state is detected in magnetization measurements. There is no sign of magnetic contribution from Ti atoms found in any of the studied compounds.

Logistic regression analysis of environmental and other variables and incidences of tuberculosis in respiratory patients

The objective of this study was to examine the association of 14 variables with TB in respiratory patients. The variables included: urban/rural, persons in 1200 sqft area, TB in family, crowding, smoking (family member), gender, age, education, smoking, workplace, kitchen location, cooking fuel, ventilation, and kerosene uses. Eight hundred respiratory patients were tested for sputum positive pulmonary TB; 500 had TB and 300 did not. An analysis of the unadjusted odds ratio (UOR) and adjusted OR (AOR) was undertaken using logistic regression to link the probability of TB incidences with the variables. There was an inconsistency in the significance of variables using UOR and AOR. A subset model of 4 variables (kerosene uses, ventilation, workplace, and gender) based on significant AOR was adjudged acceptable for estimating the probability of TB incidences. Uses of kerosene (AOR 2.62 (1.95, 3.54)) consistently related to incidences of TB. It was estimated that 50% reduction in kerosene uses could reduce the probability of TB by 13.29% in respiratory patients. The major recommendation was to replace kerosene uses from households with a supply of clean fuel like liquid petroleum or natural gas and rural electrification.

A framework for PM2.5 constituents-based (including PAHs) emission inventory and source toxicity for priority controls: A case study of Delhi, India

A simple mass-based emission inventory (EI) of PM_2.5 alone does not provide the information on the toxicity of the sources, as not all PM_2.5 particles are equally toxic. The PM_2.5 EI should have three inter-linked versions (i) mass-based, (ii) constituent-based and (iii) source toxicity-based. A framework (applied to the city of Delhi) to prepare constituent and source toxicity-based EI was developed. Mass emission of twelve sources was estimated for 89 constituents. The USEPA's CompTox database was used to estimate threshold concentration for the constituents of PM_2.5 for carcinogenic, chronic and acute health effects. A product of mass emission of the constituent and inverse of its threshold concentration provides an assessment of toxicity of the source. Toxicity was not linearly associated with the mass emission. Road dust, vehicles, coal, dung, wood and coal power plant showed the highest toxicity as presence of metals Cr, Co, Cd, and As make these sources disproportionately more toxic. Among PAHs, Dibenzo (ah)anthracene, showed the highest cancer risk with its 98% emission from vehicles. The soft options replacing wood, crop, coal and dung with LPG, elimination of diesel power generation, burning of waste were simple and effective measures to reduce chronic toxicity by about 40%.

Role of Dual Oxidase 1 in severe malaria

Despite important advances in malaria control, the disease is still a major public health issue in sub-Saharan Africa. Recent reports indicate over 400,000 deaths annually. Parasite resistance to known antimalarial drugs delays control and elimination. Dual oxidase 1 (Duox1), a member of the NADPH oxidase enzyme family, generates hydrogen peroxide that is used by its partner enzyme lactoperoxidase to generate antimicrobial hypothiocyanite. Malaria parasites are susceptible to hypothiocyanite in vitro. Duox1 is required for the generation of hypothiocyanite in vivo. We hypothesized that malaria parasites are susceptible to the Duox1-mediated antimicrobial system in vivo. Duox1-deficient and wild-type, Duox1-expressing mice were infected with Plasmodium berghei by either intravenous injection of sporozoites or exposure to infected mosquitos. The results indicate that Duox1-deficient mice either infected with intravenous injection of P. berghei sporozoites (p&lt;0.004) or by exposure to P. berghei-infected mosquito bites (p&lt;0.002), have significantly higher blood parasite density at peak parasitemia compared to wild-type mice. Survival data indicated that Duox1-deficient mice are more susceptible to P. berghei infection than control animals (p&lt;0.03 for intravenous infection, p&lt;0.02 for exposure to mosquito bites). Histopathological analysis of brain tissues revealed a slightly higher number of indices of cerebral pathology including cerebrovascular infected red blood cells and hemozoin accumulation, hemostasis, and hemorrhage. Overall, these data propose a novel role of Duox1 in delaying the onset of parasitemia and clinical outcomes in malaria infection.

External disturbances impact helminth-host interactions by affecting dynamics of infection, parasite traits, and host immune responses

External perturbations, such as multispecies infections or anthelmintic treatments, can alter host-parasite interactions with consequences on the dynamics of infection. While the overall profile of infection might appear fundamentally conserved at the host population level, perturbations can disproportionately affect components of parasite demography or host responses, and ultimately impact parasite fitness and long-term persistence.We took an immuno-epidemiological approach to this reasoning and examined a rabbit-helminth system where animals were trickle-dosed with either one or two helminth species, treated halfway through the experiment with an anthelmintic and reinfected one month later following the same initial regime. Parasite traits (body length and fecundity) and host immune responses (cytokines, transcription factors, antibodies) were quantified at fixed time points and compared before and after drug treatment, and between single and dual infections.Findings indicated a resistant host phenotype to Trichostrongylus retortaeformis where abundance, body length, and fecundity were regulated by a protective immune response. In contrast, Graphidium strigosum accumulated in the host and, while it stimulated a clear immune reaction, many genes were downregulated both following reinfection and in dual infection, suggestive of a low host resistance.External perturbations affected parasite fecundity, including body length and number of eggs in utero, more significantly than abundance; however, there was no consistency in the parasite-immune relationships.Disentangling the processes affecting parasite life history, and how they relate to host responses, can provide a better understanding of how external disturbances impact disease severity and transmission, and how parasites strategies adjust to secure persistence at the host and the population level.

Field Relevant Variation in Ambient Temperature Modifies Density-Dependent Establishment of Plasmodium falciparum Gametocytes in Mosquitoes

The relationship between Plasmodium falciparum gametocyte density and infections in mosquitoes is central to understanding the rates of transmission with important implications for control. Here, we determined whether field relevant variation in environmental temperature could also modulate this relationship. Anopheles stephensi were challenged with three densities of P. falciparum gametocytes spanning a ~10-fold gradient, and housed under diurnal/daily temperature range ("DTR") of 9°C (+5°C and -4°C) around means of 20, 24, and 28°C. Vector competence was quantified as the proportion of mosquitoes infected with oocysts in the midguts (oocyst rates) or infectious with sporozoites in the salivary glands (sporozoite rates) at peak periods of infection for each temperature to account for the differences in development rates. In addition, oocyst intensities were also recorded from infected midguts and the overall study replicated across three separate parasite cultures and mosquito cohorts. While vector competence was similar at 20 DTR 9°C and 24 DTR 9°C, oocyst and sporozoite rates were also comparable, with evidence, surprisingly, for higher vector competence in mosquitoes challenged with intermediate gametocyte densities. For the same gametocyte densities however, severe reductions in the sporozoite rates was accompanied by a significant decline in overall vector competence at 28 DTR 9°C, with gametocyte density per se showing a positive and linear effect at this temperature. Unlike vector competence, oocyst intensities decreased with increasing temperatures with a predominantly positive and linear association with gametocyte density, especially at 28 DTR 9°C. Oocyst intensities across individual infected midguts suggested temperature-specific differences in mosquito susceptibility/resistance: at 20 DTR 9°C and 24 DTR 9°C, dispersion (aggregation) increased in a density-dependent manner but not at 28 DTR 9°C where the distributions were consistently random. Limitations notwithstanding, our results suggest that variation in temperature could modify seasonal dynamics of infectious reservoirs with implications for the design and deployment of transmission-blocking vaccines/drugs.

Sensitivity Enhancement of a Concave Shaped Optical Fiber Refractive Index Sensor Covered with Multiple Au Nanowires

In the present paper, a new kind of concave shaped refractive index sensor (CSRIS) exploiting localized surface plasmon resonance (LSPR) is proposed and numerically optimized. The LSPR effect between polaritons and the core guided mode of designed CSRIS is used to enhance the sensing performance. The sensor is characterized for two types of sensing structures coated with gold (Au) film and Au nanowires (AuNWs), respectively. The influence of structural parameters such as the distance (D) of the concave shaped channel (CSC) from the core, the diameter of the nanowire (d_n) and the size (s) of the CSC are investigated here. In comparison to Au film, the AuNWs are shown to significantly enhance the sensitivity and the performance of the designed sensor. An enhanced sensitivity of 4471 nm/RIU (refractive index unit) is obtained with AuNWs, for a wide range of analytes refractive index (n_a) varying between 1.33 to 1.38. However, for conventional Au film; the sensitivity of 808.57 nm/RIU is obtained for the same range of analytes.

Cryogenically preserved RBCs support gametocytogenesis of Plasmodium falciparum in vitro and gametogenesis in mosquitoes

BACKGROUND

The malaria Eradication Research Agenda (malERA) has identified human-to-mosquito transmission of Plasmodium falciparum as a major target for eradication. The cornerstone for identifying and evaluating transmission in the laboratory is standard membrane feeding assays (SMFAs) where mature gametocytes of P. falciparum generated in vitro are offered to mosquitoes as part of a blood-meal. However, propagation of "infectious" gametocytes requires 10-12 days with considerable physico-chemical demands imposed on host RBCs and thus, "fresh" RBCs that are ≤ 1-week old post-collection are generally recommended. However, in addition to the costs, physico-chemical characteristics unique to RBC donors may confound reproducibility and interpretation of SMFAs. Cryogenic storage of RBCs ("cryo-preserved RBCs") is accepted by European and US FDAs as an alternative to refrigeration (4 °C) for preserving RBC "quality" and while cryo-preserved RBCs have been used for in vitro cultures of other Plasmodia and the asexual stages of P. falciparum, none of the studies required RBCs to support parasite development for > 4 days.

RESULTS

Using the standard laboratory strain, P. falciparum NF54, 11 SMFAs were performed with RBCs from four separate donors to demonstrate that RBCs cryo-preserved in the gaseous phase of liquid nitrogen (- 196 °C) supported gametocytogenesis in vitro and subsequent gametogenesis in Anopheles stephensi mosquitoes. Overall levels of sporogony in the mosquito, as measured by oocyst and sporozoite prevalence, as well as oocyst burden, from each of the four donors thawed after varying intervals of cryopreservation (1, 4, 8, and 12 weeks) were comparable to using ≤ 1-week old refrigerated RBCs. Lastly, the potential for cryo-preserved RBCs to serve as a suitable alternative substrate is demonstrated for a Cambodian isolate of P. falciparum across two independent SMFAs.

CONCLUSIONS

Basic guidelines are presented for integrating cryo-preserved RBCs into an existing laboratory/insectary framework for P. falciparum SMFAs with significant potential for reducing running costs while achieving greater reliability. Lastly, scenarios are discussed where cryo-preserved RBCs may be especially useful in enhancing the understanding and/or providing novel insights into the patterns and processes underlying human-to-mosquito transmission.

Non-hysteretic first-order phase transition with large latent heat and giant low-field magnetocaloric effect

First-order magnetic transitions (FOMTs) with a large discontinuity in magnetization are highly sought in the development of advanced functional magnetic materials. Isosymmetric magnetoelastic FOMTs that do not perturb crystal symmetry are especially rare, and only a handful of material families, almost exclusively transition metal-based, are known to exhibit them. Yet, here we report a surprising isosymmetric FOMT in a rare-earth intermetallic, Eu₂In. What makes this transition in Eu₂In even more remarkable is that it is associated with a large latent heat and an exceptionally high magnetocaloric effect in low magnetic fields, but with tiny lattice discontinuities and negligible hysteresis. An active role of the Eu-5d and In-4p states and a rather unique electronic structure borne by In to Eu charge transfer, altogether result in an unusual exchange mechanism that both sets the transition in motion and unveils an approach toward developing specific magnetic functionalities ad libitum.

Changes in parasite traits, rather than intensity, affect the dynamics of infection under external perturbation

Understanding the mechanisms that generate complex host-parasite interactions, and how they contribute to variation between and within hosts, is important for predicting risk of infection and transmission, and for developing more effective interventions based on parasite properties. We used the T. retortaeformis (TR)-rabbit system and developed a state-space mathematical framework to capture the variation in intensity of infection and egg shedding in hosts infected weekly, then treated with an anthelminthic and subsequently re-challenged following the same infection regime. Experimental infections indicate that parasite intensity accumulates more slowly in the post-anthelminthic phase but reaches similar maximum numbers. By contrast, parasite EPG (eggs per gram of feces) shed from rabbits in the post-treatment phase is lower and less variable through time. Inference based on EPG alone suggests a decline in parasite intensity over time. Using a state-space model and incorporating all sources of cross-sectional and longitudinal data, we show that while parasite intensity remains relatively constant in both experimental phases, shedding of eggs into the environment is increasingly limited through changes in parasite growth. We suggest that host immunity directly modulates both the accumulation and the growth of the parasite, and indirectly affects transmission by limiting parasite length and thus fecundity. This study provides a better understanding of how within-host trophic interactions influence different components of a helminth population. It also suggests that heterogeneity in parasite traits should be addressed more carefully when examining and managing helminth infections in the absence of some critical data on parasite dynamics.

Crystal, magnetic, calorimetric and electronic structure investigation of GdScGe1-x Sb x compounds

Experimental investigations of crystal structure, magnetism and heat capacity of compounds in the pseudoternary GdScGe-GdScSb system combined with density functional theory projections have been employed to clarify the interplay between the crystal structure and magnetism in this series of RTX materials (R  =  rare-earth, [Formula: see text]  =  transition metal and X  =  p-block element). We demonstrate that the CeScSi-type structure adopted by GdScGe and CeFeSi-type structure adopted by GdScSb coexist over a limited range of compositions [Formula: see text]. Antimony for Ge substitutions in GdScGe result in an anisotropic expansion of the unit cell of the parent that is most pronounced along the c axis. We believe that such expansion acts as the driving force for the instability of the double layer CeScSi-type structure of the parent germanide. Extensive, yet limited Sb substitutions [Formula: see text] lead to a strong reduction of the Curie temperature compared to the GdScGe parent, but without affecting the saturation magnetization. With a further increase in Sb content, the first compositions showing the presence of the CeFeSi-type structure of the antimonide, [Formula: see text], coincide with the appearance of an antiferromagnetic phase. The application of a finite magnetic field reveals a jump in magnetization toward a fully saturated ferromagnetic state. This antiferro-ferromagnetic transformation is not associated with a sizeable latent heat, as confirmed by heat capacity measurements. The electronic structure calculations for [Formula: see text] indicate that the key factor in the conversion from the ferromagnetic CeScSi-type to the antiferromagnetic CeFeSi-type structure is the disappearance of the induced magnetic moments on Sc. For the parent antimonide, heat capacity measurements indicate an additional transition below the main antiferromagnetic transition.

Effect of condensed tannins from Ficus infectoria and Psidium guajava leaf meal mixture on nutrient metabolism, methane emission and performance of lambs

Objective

The study examined the effect of condensed tannins (CT) containing Ficus infectoria and Psidium guajava leaf meal mixture (LMM) supplementation on nutrient metabolism, methane emission and performance of lambs.

Methods

Twenty four lambs of ~6 months age (average body weight 10.1±0.60 kg) were randomly divided into 4 dietary treatments (CT-0, CT-1, CT-1.5, and CT-2 containing 0, 1.0, 1.5, and 2.0 percent CT through LMM, respectively) consisting of 6 lambs each in a completely randomized design. All the lambs were offered a basal diet of wheat straw ad libitum, oat hay (100 g/d) along with required amount of concentrate mixture to meet their nutrient requirements for a period of 6 months. After 3 months of experimental feeding, a metabolism trial of 6 days duration was conducted on all 24 lambs to determine nutrient digestibility and nitrogen balance. Urinary excretion of purine derivatives and microbial protein synthesis were determined using high performance liquid chromatography. Respiration chamber study was started at the mid of 5th month of experimental feeding trial. Whole energy balance trials were conducted on individual lamb one after the other, in an open circuit respiration calorimeter.

Results

Intake of dry matter and organic matter (g/d) was significantly (p<0.05) higher in CT-1.5 than control. Digestibility of various nutrients did not differ irrespective of treatments. Nitrogen retention and microbial nitrogen synthesis (g/d) was significantly (p<0.01) higher in CT-1.5 and CT-2 groups relative to CT-0. Total body weight gain (kg) and average daily gain (g) were significantly (linear, p<0.01) higher in CT-1.5 followed by CT-1 and CT-0, respectively. Feed conversion ratio (FCR) by lambs was significantly (linear, p<0.01) better in CT-1.5 followed by CT-2 and CT-0, respectively. Total wool yield (g; g/d) was linearly (p<0.05) higher for CT-1.5 than CT-0. Methane emission was linearly decreased (p<0.05) in CT groups and reduction was highest (p<0.01) in CT-2 followed by CT-1.5 and CT-1. Methane energy (kcal/d) was linearly decreased (p<0.05) in CT groups.

Conclusion

The CT supplementation at 1% to 2% of the diet through Ficus infectoria and Psidium guajava LMM significantly improved nitrogen metabolism, growth performance, wool yield, FCR and reduced methane emission by lambs.

Clinical and demographic characteristics of CLL patients receiving first-line bendamustine plus rituximab using the Flatiron Health database

e19010

Background: Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in the Western world, with 20,110 new cases estimated for 2017 in the US alone. Combination therapy with bendamustine plus rituximab (BR) is among the approved first-line therapies for CLL patients without the 17p deletion. The purpose of this analysis was to characterize CLL patients receiving first-line BR therapy using real-world data. Methods: CLL patients (ICD-9: 204.1x or ICD-10: C91.1x, C83.0x) receiving first-line BR therapy between 11/01/2008 and 11/01/2016 were identified in the Flatiron Health electronic health records database. This database is a large, longitudinal, demographically and geographically diverse database consisting of 250 cancer clinics representing more than 1.5 million active US cancer patients. Results: Of the 2736 CLL patients in the database, 738 patients (male = 70%; mean age = 68.71 years, SD = 9.070) received first-line BR therapy. The majority of patients received treatment in a community setting (93%; 7% in academic hospitals). Prior to first-line BR therapy, immunoglobulin heavy chain variable region ( IGHV) mutation analysis was conducted in 21% of patients, of which 46% were IGHV mutated. Fluorescence in situhybridization (FISH) testing was conducted in 60% of patients: 17p deletion was detected in 8% and 11q deletion in 19%. Trisomy 12 and 13q deletion as a single abnormality was identified in 17% and 27% of tested patients, respectively. Conclusions: CLL patients from the Flatiron database initiating first-line BR therapy have an older median age, male predominance, and community-based treatment setting, which offers a more real-world patient population in comparison with patients reported from clinical trials. Less than a quarter of these CLL patients were tested for IGHV mutations, and only 60% were tested for FISH. The low frequency of testing prior to first-line therapy is similar to other published registry data. This representative patient population offers an insight into the real-world use of BR in CLL patients.

Differences in health care costs and utilization: BR vs RCHOP in patients with follicular lymphoma

e19049

Background: Follicular lymphoma (FL) is the most common subtype of indolent non-Hodgkin lymphoma (iNHL) with an incidence of more than 1500 cases annually and comprising 35% of all iNHL cases in North America. Combination chemotherapy with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (RCHOP) or bendamustine plus rituximab (BR) are both category 1–approved first-line therapies. This analysis examined differences in healthcare costs and utilization between two cohorts of newly diagnosed FL patients undergoing BR or RCHOP therapy. Methods: Newly diagnosed FL patients from 1/1/2006 to 7/31/2016 treated with first-line RCHOP or BR were identified in the Truven Health MarketScan Research Databases. Inclusion criteria were age ≥18 years and continuous enrollment from 3 months before to 1 month after the index date (eg, first prescription for RCHOP/BR). Healthcare utilization and costs were calculated on a per month basis from the index date to 6 months post-index date. Costs included all payments made by insurance providers except for pharmacy claims. Healthcare utilization variables included number of outpatient visits, emergency room (ER) visits (yes/no), and hospitalizations (yes/no). Logistic regression and general linear models were used to test for differences. Results: Of the 6460 FL patients (male = 55%; mean age = 60.46 years, SD = 12.56) identified, 2360 were in the BR cohort and 4100 patients were in the RCHOP cohort. At baseline, the BR cohort was significantly older; had more comorbid conditions, lower costs, and fewer outpatient visits; and was less likely to have an ER visit or hospitalization relative to RCHOP patients. Over the first 6 months of therapy, controlling for baseline differences, the BR group experienced significantly lower costs and fewer outpatient visits. The BR cohort was also significantly less likely to be admitted to the ER or experience a hospitalization. Conclusions: The results of this analysis suggest that, in general, the healthcare costs and utilization of FL patients receiving BR is significantly lower than for RCHOP patients. These results support the emerging prominence of BR as an effective and safe first-line treatment option for FL patients.

The emotional journey among caregivers of patients with leukemia: The caregivers’ perspective using social media listening

e18568

Background: The burden of cancer has largely focused on the patient. However, caregivers also experience considerable burden. The study's aim was to use social media posts to better understand the emotional journey of caregivers who provide care for patients with leukemia from their own perspective. Methods: Publicly available social media posts (in English) mentioning chronic myeloid leukemia (CML), chronic lymphocytic leukemia (CLL), and acute promyelocytic leukemia (APL) from blogs, discussion boards, and Facebook were collected and linguistically analyzed. Results: A total of 145 social media posts by CML caregivers, 149 posts by CLL caregivers, and 65 posts by APL caregivers were analyzed. Common themes emerged among CML, CLL, and APL caregivers as they journeyed from pre-diagnosis, to diagnosis, and to survivorship alongside their loved ones. At the pre-diagnosis phase, caregivers expressed uneasiness or worry about the symptoms their loved ones were experiencing. Additionally, caregivers were often frustrated with doctors because they felt that their loved ones’ symptoms were ignored, which led to a delay in diagnosis. Once the diagnosis was confirmed, caregivers were shocked and scared. Further, caregivers were desperate for information on the disease and what the future would hold. During the survivorship phase of the journey, an amalgam of complex positive and negative emotions emerged among caregivers. Caregivers can become obsessed with finding ways to treat their loved ones, including use of alternative medicine. Caregivers experienced both positive (a more “enriched relationship”) and negative (felt alone or pushed away) relationship changes. Many caregivers were proud of their loved ones’ remission and felt triumphant. Caregivers felt a sense of gratitude toward doctors, friends, family, and social media sites for their support. Conclusions: Caregivers of CML, CLL, and APL patients experience a gamut of emotions at every stage of the disease. Additionally, the relationship between caregivers and loved ones can be negatively affected. Findings suggest that relationship counseling and social support groups could potentially relieve some caregiver burden.

Treatment patterns and characteristics of acute promyelocytic leukemia (APL) patients receiving arsenic trioxide (ATO) therapy in a real-world setting

e18522

Background: Clinical trials have shown that low-risk APL patients had significantly better outcomes when receiving first-line all-trans retinoic acid (ATRA) + ATO compared with standard ATRA + chemotherapy. Few published studies have used real-world data to describe patients using ATO and their current treatment patterns. This study used United States (US) administrative claims data to describe treatment patterns and characteristics of patients receiving first-line ATO. Methods: This retrospective, observational cohort study used claims data from the MarketScan databases. As there is no ICD-9-CM diagnosis code for APL, ATO treatment was used as a surrogate for the diagnosis of APL since ATO is typically used only in APL patients. Patients were selected if they had ≥1 claims for ATO between January 1, 2000, and June 30, 2015. Date of first use was designated the index date. To identify first-line ATO initiation, patients with ATRA or other APL-indicated chemotherapy claims any time before the index date were excluded. Variable baseline and follow-up periods consisting of ≥3 months of pre-index and ≥30 days of post-index continuous enrollment in medical and pharmacy benefit were used. Results: In total, 331 patients were identified with a subset (n = 265) having ≥2 claims for ATO. The analysis focused on these 265 patients, 54% of whom were male. Mean age was 60.6 years; 45% were covered by Medicare. The most common comorbid conditions measured were diabetes (6%), chronic obstructive pulmonary disease (5%), and congestive heart failure (4%). The most commonly selected APL treatments administered during follow-up were ATRA (17%) and daunorubicin (9%) with the use of idarubicin, cytarabine, and mitoxantrone at less than 3%. Maintenance therapy with methotrexate or 6-mercaptopurine was observed in 7% and 6% of patients, respectively. Conclusions: This is one of the first studies to examine patient characteristics and treatment patterns for first-line ATO using real-world data. Further research is needed to evaluate outcomes for patients receiving ATO as first-line therapy and to re-evaluate treatment guidelines in light of these outcomes.

Evidence of low incidence of myelodysplastic syndrome (MDS) in patients exposed to bendamustine treatment for chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL)

e19008

Background: CLL/SLL is a treatable malignancy, which is responsive to therapies that include bendamustine. However, as with many alkylating agents, there is concern for the development of secondary malignancies and MDS after exposure to bendamustine. We evaluated the risk of MDS using electronic medical records from a geographically diverse cohort of cancer patients (pts). Methods: Pathologically confirmedCLL/SLL pts with any exposure to bendamustine were identified in the Flatiron Health database (FHD, Flatiron Health, New York [122016]). This is a longitudinal US-based cohort with > 1.5 million cancer pts drawn from over 250 cancer clinics. Pts with bendamustine exposure and no history of MDS or other malignancy were included. Pts were followed longitudinally to identify incident cases of secondary malignancies or MDS. Results: Of 3140 CLL/SLL pts in the analytic cohort, 1022 met inclusion criteria. Median follow-up after bendamustine exposure was 1.7 years. Overall, 8% received bendamustine monotherapy, 84% received combination therapy, and 8% received cycles of bendamustine monotherapy and combination therapy. Of the 1022 pts, 205 (20%) had prior antineoplastic exposure, a risk factor for MDS. During the follow-up period, five pts developed MDS (0.48% of the bendamustine-exposed cohort), one of whom had prior antineoplastic exposure. Conclusions: This real-world study demonstrated that pts received bendamustine overwhelmingly as combination therapy, and 20% had prior antineoplastic exposure. MDS related to alkylators and purine analogs can have a latency of > 3 years; in this study a minority (~20%) of pts had > 3 years of follow-up. Thus, longer follow-up is required to draw definitive conclusions regarding the risk. Nevertheless, the FHD provides a source of oncology data for studying long-term outcomes of cancer pts, which have historically been difficult to capture in epidemiological studies. At a median of 1.7 years after exposure, the current study identified a low risk of MDS after controlling for potential confounders.

Tetragonal to triclinic structural transition in the prototypical CeScSi induced by a two-step magnetic ordering: a temperature-dependent neutron diffraction study of CeScSi, CeScGe and LaScSi

An investigation on the ground state magnetism of CeScSi, CeScGe (tetragonal CeScSi-type, tI12, space group I4/mmm) by temperature-dependent powder neutron diffraction has been carried out, as debated and controversial data regarding the low temperature magnetic behaviours of these two compounds were reported. Our studies reveal that, while cooling, long-range magnetic ordering in CeScSi and CeScGe takes place by a two-step process. A first transition leads to a magnetic structure with the Ce moments aligned ferromagnetically onto two neighbouring tetragonal basal a-b planes of the CeScSi-type structure; the double layers are then antiferromagnetically coupled to each other along the c-axis. The transition temperature associated with the first ordering is T _N ~ 26 K and T _N ~ 48 K for the silicide and the germanide, respectively. Here the spin directions are rigorously confined to the basal plane, with values of the Ce magnetic moments of μ _Ce  =  0.8-1.0 μ _B. A second magnetic transition, which takes place at slightly lower temperatures, results in a canting of the ordered magnetic moments out of the basal plane which is accompanied by an increase of the magnetic moment value of Ce to μ _Ce  =  1.4-1.5 μ _B. Interestingly, the second magnetic transition leads to a structural distortion in both compounds from the higher-symmetry tetragonal space group I4/mmm to the lower-symmetry and triclinic I-1 (non-standard triclinic). Magnetic symmetry analysis shows that the canted structure would not be allowed in the I4/mmm space group; this result further confirms the structural transition. The transition temperatures T _S from I4/mmm to I-1 are about 22 K in CeScSi and 36 K in CeScGe, i.e. well below the temperature of the first onset of antiferromagnetic order observed in this work (or below the ordering temperature, previously reported as either T _C or T _N). This result, along with the synchronism of the magnetic and structural transitions, suggests a magnetostructural origin of this structural distortion. We have also carried out powder neutron diffraction for LaScSi as a non-magnetically-ordering reference compound and compared the results with those of CeScSi and CeScGe compounds.

Modelling of microalgal growth and lipid production in Dunaliella tertiolecta using nitrogen-phosphorus-potassium fertilizer medium in sintered disk chromatographic glass bubble column

A comprehensive mathematical model involving NPK-10:26:26 fertilizer, NaCl, NaHCO3, light and temperature operating variables for Dunaliella tertiolecta cultivation is formulated to predict microalgae-biomass and lipid productivity. Proposed model includes Monod/Andrews kinetics for the absorption of essential nutrients into algae-biomass and Droop model involving internal nutrient cell quota for microalgae growth, assuming algae-biomass is composed of sugar, functional-pool and neutral-lipid. Biokinetic model parameters are determined by minimizing the residual-sum-of-square-errors between experimental and computed microalgae-biomass and lipid productivity using genetic algorithm. Developed model is validated with the experiments of Dunaliella tertiolecta cultivation using air-agitated sintered-disk chromatographic glass-bubble column and the effects of operating variables on microalgae-biomass and lipid productivity is investigated. Finally, parametric sensitivity analysis is carried out to know the sensitivity of model parameters on the obtained results in the input parameter space. Proposed model may be helpful in scale-up studies and implementation of model-based control strategy in large-scale algal cultivation.

Effect of tanniferous leaf meal based multi-nutrient blocks on feed intake, hematological profile, immune response, and body weight changes in Haemonchus contortus infected goats

Aim:

The aim was to assess the effect of multi nutrient block (MNB) supplementation with and without tanniferous leaf meal mixture on feed intake, hematological profile, immune response, and body weight changes of goats that were experimentally infected with Haemonchus contortus.

Materials and Methods:

Total 12 adult male goats of similar age and body weight (26.49±0.87) were allocated in 3 groups in completely randomized design. MNB supplemented in first two groups i.e. in T₁ (no infection) and T₂ (H. contortus infection @ 1500 L₃/goat) group, while, MNB-condensed tannin (CT) supplemented in T₃ (H. contortus infection @ 1500 L₃/goat + CT source). All goats were fed concentrate mixture @ 100 g/day/goat, ad lib wheat straw and MNB or MNB-CT to meet their requirement for maintenance. Body weights were recorded and blood and fecal samples were collected at 0 day and thereafter at 15 days intervals for a period of 75 days for the assessment of body weight changes, hematological profile and H. contortus loads. Both humoral and cell-mediated immune (CMI) response were assessed at the end of feeding trial.

Results:

Mean hemoglobin and packed cell volume (PCV) levels were found to be highest (p<0.001, p<0.05) in T₁ group followed by T₃ group and lowest values were observed in T₂ group. However, The PCV values between T₁ and T₃ groups were found to be statistically non-significant (p<0.05). The humoral and CMI response were significantly (p<0.036) higher in T₃ group as compared to T₂ group. MNB-CT supplementation significantly (p<0.001) reduced fecal egg counts in T₃ group as compared to MNB supplemented T₂ group.

Conclusion:

Supplementation of MNB-CT could be used as an alternative sustainable method to control H. contortus and maintained health status and performance of goats in face of parasitic challenge.

Prevalence of lymphatic filariasis in a tea garden worker population of Dibrugarh (Assam), India after six rounds of mass drug administration

BACKGROUND & OBJECTIVES

Lymphatic filariasis (LF) is endemic in the state of Assam and mass drug administration (MDA) programme for LF elimination is being implemented in the state since 2004. A study on prevalence of microfilaria (mf), disease endemicity and vector infection was carried out in a tea garden population of Dibrugarh, Assam (India) to assess the effect of ongoing MDA programme on elimination of LF.

METHODS

Finger prick thick blood smears (20 mm3) were made from individuals aged ≥2 yr old during night blood survey in between 2000-0000 hrs during the period of November 2012 to February 2013. Blood smears were dehaemoglobinised, stained with Giemsa and examined under microscope for presence of mf. Indoor resting mosquitoes were collected during 0600-1000 hrs and female Culex quinquefasciatus were dissected and examined under microscope for larval forms of the parasite.

RESULTS

A total of 634 blood smears were collected and screened for mf and 47 (7.41%) individuals were found microfilaraemic, with predominance of males (74.5%). Highest mf rate (20.0%) was seen in the males of 30-39 yr age group while in females, age group of 10-19 yr recorded maximum mf rate (5.48%). Entomological collection and dissection of Cx. quinquefasciatus revealed presence of larval stages of the parasite and infection and infectivity rates recorded were 13.20 and 3.70%, respectively. Chronic clinical manifestations in the form of elephantiasis and hydrocele were recorded in 33 (5.73%) subjects of the 575 examined.

INTERPRETATION & CONCLUSION

Mass drug administration data showed six rounds of MDA with drug distribution coverage in between 63.42 and 95.93% in the study population. Out of 634 individuals examined 47 were found microfilaraemic giving an overall infection rate of 7.41%. Mosquito vector infection and infectivity rates were 13.20 and 3.70%, respectively. Presence of high mf rate, vector infectivity rate and clinical cases in the study population after six rounds of MDA warrants concerted efforts to be made for effective implementation and monitoring of MDA for success of LF elimination programme.

Microfilarial periodicity of Wuchereria bancrofti in Assam, Northeast India

BACKGROUND & OBJECTIVES

Wuchereria bancrofti has shown nocturnal periodicity in India and other endemic countries of the world except pacific regions where non-periodic or diurnal sub-periodic forms have been reported. Presence of sub-periodic form of W. bancrofti in Andaman and Nicobar Islands, India and a case report of sub- periodic form of W. bancrofti from Mysore, India provide basis for exploring the periodicity pattern of microfilaria of W. bancrofti prevalent in Assam, Northeastern region of India. State of Assam has unique geographical location as its Northeastern region shares international boundaries with Nepal, China, Bhutan, Myanmar and Bangladesh. Evolutionary association of W. bancrofti found in Assam is not known and possibility of its link with W. bancrofti form, prevalent in neighbouring countries may not be ruled out. Hence, this study was undertaken to know the microfilarial periodicity of W. bancrofti in Assam.

METHODS

Ten microfilaria positive adult male individuals having moderate to high microfilaraemia were selected. Informed written consent from each participant was obtained. The presence of microfilaria was observed at two hourly intervals over a period of 24 h using 50 μl of finger prick peripheral blood samples. Peripheral blood smears were processed, stained and examined under microscope and microfilaria counts were recorded.

RESULTS

Data collected were calculated and analyzed using modified statistical method, and the periodicity curve was prepared. Typical nocturnal periodicity was observed at a peak time of 0003 hrs with a periodicity index of 136.2.

INTERPRETATION & CONCLUSION

Analysis of the data revealed nocturnal periodicity of the W. bancrofti prevalent in the Assam with peak periodicity about one hour ahead of the other states in India. Findings will be helpful in evaluation and monitoring of ongoing MDA programme for elimination of LF in Assam.

Infections do not predict shedding in co-infections with two helminths from a natural system

Given the health and economic burden associated with the widespread occurrence of co-infections in humans and agricultural animals, understanding how coinfections contribute to host heterogeneity to infection and transmission is critical if we are to assess risk of infection based on host characteristics. Here, we examine whether host heterogeneity to infection leads to similar heterogeneity in transmission in a population of rabbits single and co-infected with two helminths and monitored monthly for eight years. Compared to single infections, co-infected rabbits carried higher Trichostrongylus retortaeformis intensities, shorter worms with fewer eggs in utero, and shed similar numbers of parasite eggs. In contrast, the same co-infected rabbits harbored fewer Graphidium strigosum with longer bodies and more eggs in utero, and shed more eggs of this helminth. A positive density-dependent relationship between fecundity and intensity was found for T. retortaeformis but not G. strigosum in co-infected rabbits. Juvenile rabbits contributed to most of the infection and shedding of T. retortaeformis, while adult hosts were more important for G. strigosum dynamics of infection and transmission, and this pattern was consistent in single and co-infected individuals. This host-parasite system suggests that we cannot predict the pattern of parasite shedding during co-infections based on intensity of infection alone. We suggest that a mismatching between susceptibility and infectiousness should be expected in helminth coinfections and should not be overlooked.

Randomized phase II study of carboplatin and etoposide with or without obatoclax mesylate in extensive-stage small cell lung cancer

OBJECTIVE

This randomized phase II study assessed the efficacy and safety of obatoclax mesylate, a small-molecule Bcl-2 inhibitor, added to carboplatin/etoposide chemotherapy as initial treatment for extensive-stage small-cell lung cancer (ES-SCLC).

MATERIALS AND METHODS

Chemotherapy-naïve subjects with ES-SCLC and Eastern Cooperative Oncology Group performance status (ECOG PS) 0-2 received carboplatin/etoposide with (CbEOb) or without (CbE) obatoclax for up to six cycles. Responders to CbEOb could receive maintenance obatoclax until disease progression. The primary endpoint was objective response rate (ORR).

RESULTS

155 subjects (median age 62, 58% male, 10% ECOG PS 2) were treated with CbEOb (n=77) or CbE (n=78); 65% and 59% of subjects, respectively, completed six cycles. ORR was 62% with CbEOb versus 53% with CbE (1-sided p=0.143). Clinical benefit (ORR+ stable disease) trended better with CbEOb (81% versus 68%; p=0.054). Median progression-free survival (PFS) and overall survival (OS) were 5.8 months (95% confidence interval [CI]: 5.3-6.5) and 10.5 months (8.9-13.8) with CbEOb and 5.2 months (95% CI: 4.1-5.7) and 9.8 months (7.2-11.2) with CbE. Median OS was 10.5 months (95% CI: 8.9-13.8) and 9.8 months (7.2-11.2) with a nonsignificant hazard ratio for OS, 0.823; 1-sided p=0.121. Grade 3/4 adverse events (AEs) were primarily hematologic and similar in frequency between treatment arms. Obatoclax-related somnolence and euphoria were grade 1/2, transient, and did not require treatment discontinuation.

CONCLUSION

Obatoclax was well tolerated when added to carboplatin/etoposide in first-line treatment of ES-SCLC, but failed to significantly improve ORR, PFS, or OS.

Length weight relationship and condition factor of selected freshwater fish species found in river Ganga, Gomti and Rapti, India

This study is based on the length-weight relationships (LWRs) of 2148 fishes, belonging to 8 families, 12 genera and 15 freshwater fish species (Wallago attu, Rite rita, Sperato seenghala, Sperota aor, Mostacembalus armatus, Macrognathus puncolus, Gudusia chopra, Clupisoma garua, Puntius sophore, Puntius ticto, Rasbora daniconius, Amblypharyngodon mole, Chanda noma, Colisa fociatus and Colisa sota) captured from river Ganga, Gomti and Rapti during May 2011 to March 2012. The growth coefficient (b) values varied between 1.30 and 3.07, with the mean b = 2.03 at p< 0.001. The condition factor (K) varied considerably from 0.76 and 2.95, with a mean K = 1.43 which may be attributed to different environmental conditions of the river basin. The objective was to evaluate the pattern of LWRs and condition factors of the freshwater fish species of the main Ganga and tributaries which serves as baseline for other tropical Indian rivers and tributaries.

Immuno-epidemiology of chronic bacterial and helminth co-infections: observations from the field and evidence from the laboratory

Co-infections can alter the host immune responses and modify the intensity and dynamics of concurrent parasitic species. The extent of this effect depends on the properties of the system and the mechanisms of host-parasite and parasite-parasite interactions. We examined the immuno-epidemiology of a chronic co-infection to reveal the immune mediated relationships between two parasites colonising independent organs, and the within-host molecular processes influencing the dynamics of infection at the host population level. The respiratory bacterium, Bordetella bronchiseptica, and the gastrointestinal helminth, Graphidium strigosum, were studied in the European rabbit (Oryctolagus cuniculus), using long-term field data and a laboratory experiment. We found that 65% of the rabbit population was co-infected with the two parasites; prevalence and intensity of co-infection increased with rabbit age and exhibited a strong seasonal pattern with the lowest values recorded during host breeding (from April to July) and the highest in the winter months. Laboratory infections showed no significant immune-mediated effects of the helminth on bacterial intensity in the lower respiratory tract but a higher abundance was observed in the nasal cavity during the chronic phase of the infection, compared with single bacterial infections. In contrast, B. bronchiseptica enhanced helminth intensity and this was consistent throughout the 4-month trial. These patterns were associated with changes in the immune profiles between singly and co-infected individuals for both parasites. This study confirmed the general observation that co-infections alter the host immune responses but also highlighted the often ignored role of bacterial infection in helminth dynamics. Additionally, we showed that G. strigosum had contrasting effects on B. bronchiseptica colonising different parts of the respiratory tract. At the host population level our findings suggest that B. bronchiseptica facilitates G. strigosum infection, and re-infection with G. strigosum assists in maintaining bacterial infection in the upper respiratory tract and thus long-term persistence.

Network model of immune responses reveals key effectors to single and co-infection dynamics by a respiratory bacterium and a gastrointestinal helminth

Co-infections alter the host immune response but how the systemic and local processes at the site of infection interact is still unclear. The majority of studies on co-infections concentrate on one of the infecting species, an immune function or group of cells and often focus on the initial phase of the infection. Here, we used a combination of experiments and mathematical modelling to investigate the network of immune responses against single and co-infections with the respiratory bacterium Bordetella bronchiseptica and the gastrointestinal helminth Trichostrongylus retortaeformis. Our goal was to identify representative mediators and functions that could capture the essence of the host immune response as a whole, and to assess how their relative contribution dynamically changed over time and between single and co-infected individuals. Network-based discrete dynamic models of single infections were built using current knowledge of bacterial and helminth immunology; the two single infection models were combined into a co-infection model that was then verified by our empirical findings. Simulations showed that a T helper cell mediated antibody and neutrophil response led to phagocytosis and clearance of B. bronchiseptica from the lungs. This was consistent in single and co-infection with no significant delay induced by the helminth. In contrast, T. retortaeformis intensity decreased faster when co-infected with the bacterium. Simulations suggested that the robust recruitment of neutrophils in the co-infection, added to the activation of IgG and eosinophil driven reduction of larvae, which also played an important role in single infection, contributed to this fast clearance. Perturbation analysis of the models, through the knockout of individual nodes (immune cells), identified the cells critical to parasite persistence and clearance both in single and co-infections. Our integrated approach captured the within-host immuno-dynamics of bacteria-helminth infection and identified key components that can be crucial for explaining individual variability between single and co-infections in natural populations.

Infections with different infecting agents can alter the immune response against any one parasite and the relative abundance and persistence of the infections within the host. This is because the immune system is not compartmentalized but acts as a whole to allow the host to maintain control of the infections as well as repair damaged tissues and avoid immuno-pathology. There is no comprehensive understanding of the immune responses during co-infections and of how systemic and local mechanisms interact. Here we integrated experimental data with mathematical modelling to describe the network of immune responses of single and co-infection by a respiratory bacterium and a gastrointestinal helminth. We were able to identify key cells and functions responsible for clearing or reducing both parasites and showed that some mechanisms differed between type of infection as a result of different signal outputs and cells contributing to the immune processes. This study highlights the importance of understanding the immuno-dynamics of co-infection as a host response, how immune mechanisms differ from single infections and how they may alter parasite persistence, impact and abundance.

Snapshot of spatio-temporal cytokine responses to single and co-infections with helminths and bacteria

Cytokines play a key role in maintaining communication between organs and in so doing modulate the interaction between concurrent infections. The extent of these effects depends on the properties of the organ infected and the intensity and type of infections. To determine systemic bystander effects among organs, IFN-γ, IL-4 and IL-10 gene expression was quantified at 7 days post-challenge in directly infected and uninfected organs during single and co-infections with the respiratory bacterium Bordetella bronchiseptica and the gastrointestinal helminths Graphidium strigosum and Trichostrongylus retortaeformis. Results showed that cytokine expression in a specific organ was influenced by the type of infection occurring in another organ, and this bystander effect was more apparent in some organs than others. Within the same organ the relative cytokine expression was consistent across infections, although some cytokines were more affected by bystander effects than others. For the infected gastrointestinal tract, a stronger cytokine response was observed in the tissue that harbored the majority of helminths (i.e. duodenum and fundus). Overall, co-infections altered the intensity but to a lesser extent the relative cytokine profile against the focal infection, indicating clear bystander effects and low organ compartmentalization. However, organs appear to actively modulate cytokine expression to avoid potential immuno-pathological consequences.

Instability range of microsolvated multiply charged negative ions: prediction from detachment energy of stable hydrated clusters

We have presented a first-principle theory-based derivation of an exact expression for the solvent number-dependent electron-detachment energy of a solvated species in the thermodynamic limit. We also propose a generalized equation bridging the electron detachment energies for small and infinitely large clusters, thus providing a new route to calculate the ionization potential of a negatively charged ion from the electron-detachment energies of its stable hydrated clusters. Most importantly, it has the ability to predict the instability range of microhydrated anions. The calculated results for the ionization potential for a number of ions are found to be in good agreement with the available experimental results, and the predicted instability range for the doubly charged anions SO₄²⁻ and C₂O₄²⁻ is also consistent with experimental and ab initio results.

2-Azetidinone--a new profile of various pharmacological activities

2-azetidinone, a β-lactam four member heterocyclic compound involved in research aimed to evaluate new products that possess interesting biological activities. These compounds reported for their antimicrobial and antifungal activities. Successful introduction of aztreonam as a potent inhibitor of cephalosporinase and ezetimibe as a cholesterol absorption inhibitor proved potential of 2-azetidinone moiety. Subsequently 2-azetidinones were highlighted as a potent mechanism based inhibitor of several enzymes like human tryptase, chymase, thrombin, leukocyte elastase, human cytomegalovirus protease and serine protease enzyme. These derivatives also known to possess antitubercular, anti-inflammatory, antitumor, anti-HIV, antiparkinsonian, antidiabetic and vasopressin V1a antagonist activity. The present review article focuses on the pharmacological profile of 2-azetidinones with their potential activities.

Immune regulation of a chronic bacteria infection and consequences for pathogen transmission

Background

The role of host immunity has been recognized as not only playing a fundamental role in the interaction between the host and pathogen but also in influencing host infectiousness and the ability to shed pathogens. Despite the interest in this area of study, and the development of theoretical work on the immuno-epidemiology of infections, little is known about the immunological processes that influence pathogen shedding patterns.

Results

We used the respiratory bacterium Bordetella bronchiseptica and its common natural host, the rabbit, to examine the intensity and duration of oro-nasal bacteria shedding in relation to changes in the level of serum antibodies, blood cells, cytokine expression and number of bacteria colonies in the respiratory tract. Findings show that infected rabbits shed B. bronchiseptica by contact up to 4.5 months post infection. Shedding was positively affected by number of bacteria in the nasal cavity (CFU/g) but negatively influenced by serum IgG, which also contributed to the initial reduction of bacteria in the nasal cavity. Three main patterns of shedding were identified: i- bacteria were shed intermittently (46% of individuals), ii- bacteria shedding fell with the progression of the infection (31%) and iii- individuals never shed bacteria despite being infected (23%). Differences in the initial number of bacteria shed between the first two groups were associated with differences in the level of serum antibodies and white blood cells. These results suggest that the immunological conditions at the early stage of the infection may play a role in modulating the long term dynamics of B. bronchiseptica shedding.

Conclusions

We propose that IgG influences the threshold of bacteria in the oro-nasal cavity which then affects the intensity and duration of individual shedding. In addition, we suggest that a threshold level of infection is required for shedding, below this value individuals never shed bacteria despite being infected. The mechanisms regulating these interactions are still obscure and more studies are needed to understand the persistence of bacteria in the upper respiratory tract and the processes controlling the intensity and duration of shedding.

Influence of an enzyme cocktail and phytase individually or in combination in Ven Cobb broiler chickens

1. An experiment (21 d) was conducted to determine if the response of chicks to a cocktail of xylanase, amylase, and protease (XAP) or Escherichia coli-derived phytase individually or in combination when fed a nutritionally marginal maize-soybean meal diet is age-dependent. 2. A total of 250 one-day-old Ven Cobb broiler chicks were allocated to 5 dietary treatments in a randomised complete block design. The treatments were as follows: (1) positive control with supplemental inorganic P; (2) negative control (NC) marginal in P and ME; (3) NC plus XAP to provide (per kg of diet) 650, 1650 and 4000 U of xylanase, amylase, and protease, respectively; (4) NC plus phytase added to provide 1000 phytase units/kg; and (5) NC plus a combination of XAP and phytase. 3. Low ME and P in the NC diet depressed weight gain and gain:feed. A cocktail of XAP alone did not improve performance, but phytase supplementation improved weight gain. The enzymes were additive in their effects on growth performance. 4. The enzymes had no effect on ileal digestible energy. Ileal N digestibility was higher in diets with XAP or phytase individually compared with NC. Both phytase and XAP individually and in combination improved ileal P digestibility compared with NC. 5. Total tract nutrient retention and ME increased as the birds grew older. There were age x diet interactions in total tract retention of P and Ca; improvement in P retention due to phytase use decreased by 50% as the chicks matured. 6. The current study shows that a combination of XAP and phytase improved performance, but the enhancement in performance appears to be due mainly to phytase. Both XAP and phytase were effective in improving P digestibility and retention of chicks receiving nutritionally marginal maize-soybean meal. 7. The data also showed that the chicks benefited more from the enzyme addition at a younger age and that the contribution of the enzymes to nutrient retention decreased with age in chickens.

Antigenic Variation among Bordetella: Bordetella bronchiseptica strain MO149 expresses a novel o chain that is poorly immunogenic

The O chain polysaccharide (O PS) of Bordetella bronchiseptica and Bordetella parapertussis lipopolysaccharide is a homopolymer of 2,3-diacetamido-2,3-dideoxygalacturonic acid (GalNAc3NAcA) in which some of the sugars are present as uronamides. The terminal residue contains several unusual modifications. To date, two types of modification have been characterized, and a survey of numerous strains demonstrated that each contained one of these two modification types. Host antibody responses against the O PS are directed against the terminal residue modifications, and there is little cross-reactivity between the two types. This suggests that Bordetella O PS modifications represent a means of antigenic variation. Here we report the characterization of the O PS of B. bronchiseptica strain MO149. It consists of a novel two-sugar repeating unit and a novel terminal residue modification, with the structure Me-4-alpha-L-GalNAc3NAcA-(4-beta-D-GlcNAc3NAcA-4-alpha-L-GalNAc3NAcA-)(5-6)-, which we propose be defined as the B. bronchiseptica O3 PS. We show that the O3 PS is very poorly immunogenic and that the MO149 strain contains a novel wbm (O PS biosynthesis) locus. Thus, there is greater diversity among Bordetella O PSs than previously recognized, which is likely to be a result of selection pressure from host immunity. We also determine experimentally, for the first time, the absolute configuration of the diacetimido-uronic acid sugars in Bordetella O PS.

Heterotransplant mouse model cohorts of human malignancies: A novel platform for Systematic Preclinical Efficacy Evaluation of Drugs (SPEED)

Advances in molecular biology demonstrate that cancer is heterogeneous disease necessitating a personalized management approach. This is introducing a paradigm shift in clinical trial designs where molecular characterization of cancers is assuming importance equal to (or even more than) the traditional histologic diagnosis as the eligibility criterion for randomized clinical trials of new therapies. Recommendations have been made to gather the molecular information from clinical phase II trials distinguishing responding from non responding tumors for subsequent planning of large scale phase III trials. However by the time we reach phase II level, more than a billion dollars apart from years of research have been invested. It would be therefore prudent to conceptualize laboratory based platforms to obtain the proof of concept as early as possible, even before embarking upon the pivotal clinical trials. In this regard, we hereby propose and detail a novel preclinical platform incorporating the existing mouse models to address the issue of tumor heterogeneity in a systematic manner through creation of a setting similar to phase II trials in human patients. By providing critical information about a drug's efficacy and the molecular determinants of response early on, this platform would potentially provide a solid foundation to build avant-garde clinical trials integrating recent advances in molecular medicine.

Effect of change in symptoms, respiratory status, nutritional profile and quality of life on response to treatment for advanced non-small cell lung cancer

INTRODUCTION

Quality of life (QOL), and pulmonary and nutritional parameters are important outcome measures during treatment of lung cancer; however, the effect of chemotherapy on these factors and their relationship with clinical response is unclear.

METHODS

Patients with non-small cell lung cancer (NSCLC) were evaluated for symptom profile, nutritional status (using anthropometry), pulmonary functions by spirometry and six minute walk distance (6 MWD), and QOL using the WHO-QOL Bref 26 questionnaire, before and after chemotherapy.

RESULTS

Forty-four patients were studied (mean (SD) age, 55 (10) years, 75% males). The majority (98%) had stage III or IV disease and 72% were current / ex-smokers with median pack-years of 27.0 (range, 0.5-90). Some 61% had a Karnofsky Performance Scale (KPS) 70 or 80. The commonest symptoms were coughing, dyspnea, chest pain, anorexia and fever (79%, 72%, 68%, 57% and 40%, respectively). The mean (SD) 6 MWD was 322.5 (132.6) meters. The mean (SD) percentage forced vital capacity (FVC %), and forced expiratory volume in one second (FEV1 %) were 64.7 (18.8) and 57.8 (19.4), respectively. The mean (SD) QOL scores for the physical, psychological, social, and environmental domains were 52.9 (20.5), 56.1 (17.9), 64.5 (21.8), 57.1 (16.6), respectively. Fourteen patients (32%) responded to chemotherapy. Non-responders had significantly higher baseline occurrence of fever, anorexia, and weight loss, higher pack-years of smoking and poorer KPS compared to responders. Overall, chemotherapy caused significant decline in the frequency of coughing, dyspnea, chest pain, fever, anorexia, weight loss, and improvement in hemoglobin and albumin levels. There was no significant improvement in pulmonary functions, nutritional status, or QOL scores after treatment.

CONCLUSIONS

Lung cancer patients have a poor QOL. Although chemotherapy provides significant symptomatic benefit, this does not translate into similar benefit in respiratory and nutritional status or QOL. Patients with constitutional symptoms, higher smoking burden, and poor KPS are less likely to respond to chemotherapy. Management of NSCLC must include strategies to improve various aspects of QOL, nutritional status and pulmonary reserve to achieve comprehensive benefit.

Abstract 1599: Oral epithelium as a surrogate tissue for assessing smoking-induced molecular alterations in lungs

Background: Because lungs and oral cavity are both exposed to tobacco-carcinogens, we hypothesized that the oral epithelium undergoes molecular alterations similar to those in other airway areas and therefore may be used as a surrogate tissue to assess tobacco-induced molecular alterations in lungs.

Methods: Promoter methylation of p16 and FHIT genes was analyzed in 127 chronic smokers enrolled in a prospective randomized placebo-controlled chemoprevention trial with 1,774 samples from oral and bronchial brushes (baseline and 3-months after intervention) using methylation-specific PCR (MSP). Methylation patterns in oral tissues were correlated with bronchial methylation indices (methylated sites/total sites per subject).

Results: At baseline, promoter methylation was observed in 23%, 17%, and 35% of the bronchial tissues for p16, FHIT, and any of the two genes, respectively, which is comparable to 19%, 15%, and 31% observed in the oral tissues. Among the 125 individuals with available baseline data from both oral and bronchial tissues, strong correlations were observed between tissues from the two organ sites (P &lt; 0.0001 for both p16 and FHIT genes). Among the 39 individuals with oral tissue methylation in any of the two genes, the mean bronchial methylation index was 0.53 (±0.29) compared to only 0.27 (±0.26) for the 86 cases without oral tissue methylation (P &lt; 0.0001). Similar correlations were also observed in samples obtained at 3 months after chemopreventive intervention.

Conclusions: Oral epithelium may be used as a surrogate tissue to assess tobacco-induced molecular damages in lungs, which has potential implications in lung cancer prevention trials.

Delta DNMT3B variants regulate DNA methylation in a promoter-specific manner

DNA methyltransferase 3B (DNMT3B) is critical in de novo DNA methylation during development and tumorigenesis. We recently reported the identification of a DNMT3B subfamily, DeltaDNMT3B, which contains at least seven variants, resulting from alternative pre-mRNA splicing. DeltaDNMT3Bs are the predominant expression forms of DNMT3B in human lung cancer. A strong correlation was observed between the promoter methylation of RASSF1A gene but not p16 gene (both frequently inactivated by promoter methylation in lung cancer) and expression of DeltaDNMT3B4 in primary lung cancer, suggesting a role of DeltaDNMT3B in regulating promoter-specific methylation of common tumor suppressor genes in tumorigenesis. In this report, we provide first experimental evidence showing a direct involvement of DeltaDNMT3B4 in regulating RASSF1A promoter methylation in human lung cancer cells. Knockdown of DeltaDNMT3B4 expression by small interfering RNA resulted in a rapid demethylation of RASSF1A promoter and reexpression of RASSF1A mRNA but had no effect on p16 promoter in the lung cancer cells. Conversely, normal bronchial epithelial cells with stably transfected DeltaDNMT3B4 gained an increased DNA methylation in RASSF1A promoter but not p16 promoter. We conclude that promoter DNA methylation can be differentially regulated and DeltaDNMT3Bs are involved in regulation of such promoter-specific de novo DNA methylation.

Ursolic acid inhibits STAT3 activation pathway leading to suppression of proliferation and chemosensitization of human multiple myeloma cells

The activation of signal transducers and activators of transcription 3 (STAT3) has been linked with the proliferation of a variety of human cancer cells, including multiple myeloma. Agents that can suppress STAT3 activation have potential for prevention and treatment of cancer. In the present report, we tested an agent, ursolic acid, found in basil, apples, prunes, and cranberries, for its ability to suppress STAT3 activation. We found that ursolic acid, a pentacyclic triterpenoid, inhibited both constitutive and interleukin-6-inducible STAT3 activation in a dose- and time-dependent manner in multiple myeloma cells. The suppression was mediated through the inhibition of activation of upstream kinases c-Src, Janus-activated kinase 1, Janus-activated kinase 2, and extracellular signal-regulated kinase 1/2. Vanadate treatment reversed the ursolic acid-induced down-regulation of STAT3, suggesting the involvement of a tyrosine phosphatase. Indeed, we found that ursolic acid induced the expression of tyrosine phosphatase SHP-1 protein and mRNA. Moreover, knockdown of SHP-1 by small interfering RNA suppressed the induction of SHP-1 and reversed the inhibition of STAT3 activation, thereby indicating the critical role of SHP-1 in the action of this triterpene. Ursolic acid down-regulated the expression of STAT3-regulated gene products such as cyclin D1, Bcl-2, Bcl-xL, survivin, Mcl-1, and vascular endothelial growth factor. Finally, ursolic acid inhibited proliferation and induced apoptosis and the accumulation of cells in G1-G0 phase of cell cycle. This triterpenoid also significantly potentiated the apoptotic effects of thalidomide and bortezomib in multiple myeloma cells. Overall, these results suggest that ursolic acid is a novel blocker of STAT3 activation that may have a potential in prevention and treatment of multiple myeloma and other cancers.

Capsaicin is a novel blocker of constitutive and interleukin-6-inducible STAT3 activation

PURPOSE

Capsaicin, a constituent of green and red peppers, has been linked with suppression of tumorigenesis through a mechanism that is not well understood. Because the transcription factor signal transducer and activator of transcription 3 (STAT3) has been closely linked with tumorigenesis, we investigated the effect of this vanilloid on the STAT3 pathway in human multiple myeloma cells.

EXPERIMENTAL DESIGN

The effect of capsaicin on both constitutive and interleukin-6-induced STAT3 activation, associated protein kinases, and STAT3-regulated gene products involved in proliferation, survival and angiogenesis, cellular proliferation, and apoptosis in multiple myeloma cells was investigated.

RESULTS

We found that capsaicin inhibited constitutive activation of STAT3 in multiple myeloma cells in a dose- and time-dependent manner, with minimum effect on STAT5. Capsaicin also inhibited the interleukin-6-induced STAT3 activation. The activation of Janus-activated kinase 1 and c-Src, implicated in STAT3 activation, was also inhibited by the vanilloid, with no effect on extracellular signal-regulated kinase 1/2 activation. Pervanadate reversed the capsaicin-induced down-regulation of STAT3, suggesting the involvement of a protein tyrosine phosphatase. Capsaicin down-regulated the expression of the STAT3-regulated gene products, such as cyclin D1, Bcl-2, Bcl-xL, survivin, and vascular endothelial growth factor. Finally, capsaicin induced the accumulation of cells in G(1) phase, inhibited proliferation, and induced apoptosis, as indicated by caspase activation. Capsaicin also significantly potentiated the apoptotic effects of Velcade and thalidomide in multiple myeloma cells. When administered i.p., capsaicin inhibited the growth of human multiple myeloma xenograft tumors in male athymic nu/nu mice.

CONCLUSION

Overall, these results suggest that capsaicin is a novel blocker of the STAT3 activation pathway, with a potential role in the prevention and treatment of multiple myeloma and other cancers.