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.

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.

Real-world safety experience of tevagrastim/ratiograstim/biograstim and tbo-filgrastim, short-acting recombinant human granulocyte colony-stimulating factors.

PURPOSE: Recombinant granulocyte colony-stimulating factors (rG-CSFs), such as filgrastim, are administered to prevent complications in patients receiving chemotherapy. In Europe, a biosimilar to filgrastim, tevagrastim/ratiograstim/biograstim, was approved in 2008. In the USA, the same product was approved as tbo-filgrastim under a 351(a) biologic license application in 2012 with the brand name Granix®. Postmarket surveillance remains a priority for monitoring the safety of biologics and biosimilars to identify rare and immunogenicity-related events. We report the global and US pharmacovigilance data for tevagrastim/ratiograstim/biograstim and tbo-filgrastim, respectively. METHODS: Cumulative exposure and adverse event data from initial approval in Europe to December 31, 2016, were collected globally from spontaneous reports submitted by healthcare professionals and consumers, scientific literature, competent authorities, and solicited case reports from non-interventional studies. A separate search was conducted on the global data set to identify reports originating from the USA and Puerto Rico to describe the US experience. RESULTS: Overall, the global safety profile of tevagrastim/ratiograstim/biograstim in the postmarket, real-world setting was comparable to clinical trial experience. Postmarket safety experience of tbo-filgrastim in the USA was consistent with global data. The most common SAEs were febrile neutropenia and decreased white blood cell count. The most common non-serious event was bone pain. There was no evidence of immunogenicity. CONCLUSIONS: This pharmacovigilance analysis indicates that postmarket experience of tevagrastim/ratiograstim/biograstim and tbo-filgrastim is consistent with clinical trials. Adverse reactions associated with the originator rG-CSF (capillary leak syndrome and glomerulonephritis) have not been observed with tevagrastim/ratiograstim/biograstim or tbo-filgrastim during the postmarket period.

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.

RmtC and RmtF 16S rRNA Methyltransferase in NDM-1-Producing Pseudomonas aeruginosa.

We investigated 16S rRNA methyltransferases in 38 blaNDM-1-positive Pseudomonas aeruginosa isolates and found RmtC in 3 isolates, 1 of which also harbored RmtF. The isolates were clonally unrelated; rmtC and rmtF genes were located on a chromosome with the blaNDM-1 gene. Strategies are needed to limit the spread of such isolates.

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.

The influence of oviposition status on measures of transmission potential in malaria-infected mosquitoes depends on sugar availability.

BACKGROUND: Like other oviparous organisms, the gonotrophic cycle of mosquitoes is not complete until they have selected a suitable habitat to oviposit. In addition to the evolutionary constraints associated with selective oviposition behavior, the physiological demands relative to an organism's oviposition status also influence their nutrient requirement from the environment. Yet, studies that measure transmission potential (vectorial capacity or competence) of mosquito-borne parasites rarely consider whether the rates of parasite replication and development could be influenced by these constraints resulting from whether mosquitoes have completed their gonotrophic cycle. METHODS: Anopheles stephensi mosquitoes were infected with Plasmodium berghei, the rodent analog of human malaria, and maintained on 1% or 10% dextrose and either provided oviposition sites ('oviposited' herein) to complete their gonotrophic cycle or forced to retain eggs ('non-oviposited'). Transmission potential in the four groups was measured up to 27 days post-infection as the rates of (i) sporozoite appearance in the salivary glands ('extrinsic incubation period' or EIP), (ii) vector survival and (iii) sporozoite densities. RESULTS: In the two groups of oviposited mosquitoes, rates of sporozoite appearance and densities in the salivary glands were clearly dependent on sugar availability, with shorter EIP and higher sporozoite densities in mosquitoes fed 10% dextrose. In contrast, rates of appearance and densities in the salivary glands were independent of sugar concentrations in non-oviposited mosquitoes, although both measures were slightly lower than in oviposited mosquitoes fed 10% dextrose. Vector survival was higher in non-oviposited mosquitoes. CONCLUSIONS: Costs to parasite fitness and vector survival were buffered against changes in nutritional availability from the environment in non-oviposited but not oviposited mosquitoes. Taken together, these results suggest vectorial capacity for malaria parasites may be dependent on nutrient availability and oviposition/gonotrophic status and, as such, argue for more careful consideration of this interaction when estimating transmission potential. More broadly, the complex patterns resulting from physiological (nutrition) and evolutionary (egg-retention) trade-offs described here, combined with the ubiquity of selective oviposition behavior, implies the fitness of vector-borne pathogens could be shaped by selection for these traits, with implications for disease transmission and management. For instance, while reducing availability of oviposition sites and environmental sources of nutrition are key components of integrated vector management strategies, their abundance and distribution are under strong selection pressure from the patterns associated with climate change.

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.

Characterisation of OXA-48-like carbapenemases in Escherichia coli and Klebsiella pneumoniae from North India.

The oxacillinase-48 (OXA-48)-like carbapenemases are class D ß-lactamases and increasingly reported in Enterobacterial species. The detection of these carbapenemases is challenging and little information is available on the epidemiology and plasmid characteristics of OXA-48-like carbapenemase producers. We detected the presence of OXA-48-like carbapenemases in 500 clinical isolates of Escherichia coli and Klebsiella pneumoniae, followed by detection of other carbapenemases, extended spectrum ß-lactamases (ESBLs) and 16S rRNA methyltransferases in OXA-48 producers. Clonal relatedness was studied using pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). Finally, plasmid characterisation was performed through conjugation experiment, S1-PFGE and Southern hybridisation. Around 40% of E. coli and K. pneumoniae isolates harboured OXA-48-like ß-lactamases. Two OXA-48 allele variants, OXA-232 and OXA-181 were detected in our study. OXA-48 producers co-harbored diverse drug-resistant genes belonging to other classes of carbapenemases, ESBLs and 16S rRNA methyltransferases. OXA-48-like carbapenemase producers exhibited high clonal diversity. Bla OXA-48 carrying plasmids were conjugative, untypable and their size was ~ 45 kb and ~ 104.5 kb in E. coli and K. pneumoniae respectively. In conclusion, OXA-48-like carbapenemases have emerged as major cause of carbapenem resistance in Enterobacteriaceae and probably still being under reported. Strict surveillance and adequate detection methods are needed to prevent the dissemination of OXA-48-like carbapenemases.

Multifaceted Role of Nanomaterials in Modulating In Vitro Seed Germination, Plant Morphogenesis, Metabolism and Genetic Engineering.

The agricultural practices of breeding, farm management and cultivation have improved production, to a great extent, in order to meet the food demands of a growing population. However, the newer challenges of climate change, global warming, and nutritional quality improvement will have to be addressed under a new scenario. Plant biotechnology has emerged as a reliable tool for enhancing crop yields by protecting plants against insect pests and metabolic engineering through the addition of new genes and, to some extent, nutritional quality improvement. Plant tissue culture techniques have provided ways for the accelerated clonal multiplication of selected varieties with the enhanced production of value-added plant products to increase modern agriculture. The in vitro propagation method has appeared as a pre-eminent approach for the escalated production of healthy plants in relatively shorter durations, also circumventing seasonal effects. However, there are various kinds of factors that directly or indirectly affect the efficiency of in vitro regeneration like the concentration and combination of growth regulators, variety/genotype of the mother plant, explant type, age of seedlings and other nutritional factors, and elicitors. Nanotechnology as one of the latest and most advanced approaches in the material sciences, and can be considered to be very promising for the improvement of crop production. Nanomaterials have various kinds of properties because of their small size, such as an enhanced contact surface area, increased reactivity, stability, chemical composition, etc., which can be employed in plant sciences to alter the potential and performance of plants to improve tissue culture practices. Implementing nanomaterials with in vitro production procedures has been demonstrated to increase the shoot multiplication potential, stress adaptation and yield of plant-based products. However, nanotoxicity and biosafety issues are limitations, but there is evidence that implies the promotion and further exploration of nanoparticles in agriculture production. The incorporation of properly designed nanoparticles with tissue culture programs in a controlled manner can be assumed as a new pathway for sustainable agriculture development. The present review enlists different studies in which treatment with various nanoparticles influenced the growth and biochemical responses of seed germination, as well as the in vitro morphogenesis of many crop species. In addition, many studies suggest that nanoparticles can be useful as elicitors for elevating levels of important secondary metabolites in in vitro cultures. Recent advancements in this field also depict the suitability of nanoparticles as a promising carrier for gene transfer, which show better efficiency than traditional Agrobacterium-mediated delivery. This review comprehensively highlights different in vitro studies that will aid in identifying research gaps and provide future directions for unexplored areas of research in important crop species.

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.

Outbreak of colistin resistant, carbapenemase (bla NDM, bla OXA-232) producing Klebsiella pneumoniae causing blood stream infection among neonates at a tertiary care hospital in India.

Infections caused by multi-drug resistant Klebsiella pneumoniae are a leading cause of mortality and morbidity among hospitalized patients. In neonatal intensive care units (NICU), blood stream infections by K. pneumoniae are one of the most common nosocomial infections leading to poor clinical outcomes and prolonged hospital stays. Here, we describe an outbreak of multi-drug resistant K. pneumoniae among neonates admitted at the NICU of a large tertiary care hospital in India. The outbreak involved 5 out of 7 neonates admitted in the NICU. The antibiotic sensitivity profiles revealed that all K. pneumoniae isolates were multi-drug resistant including carbapenems and colistin. The isolates belonged to three different sequence types namely, ST-11, ST-16 and ST-101. The isolates harboured carbapenemase genes, mainly bla NDM-1, bla NDM-5 and bla OXA-232 besides extended-spectrum ß-lactamases however the colistin resistance gene mcr-1, mcr-2 and mcr-3 could not be detected. Extensive environmental screening of the ward and healthcare personnel led to the isolation of K. pneumoniae ST101 from filtered incubator water, harboring bla NDM-5, bla OXA-232 and ESBL genes (bla CTX-M) but was negative for the mcr genes. Strict infection control measures were applied and the outbreak was contained. This study emphasizes that early detection of such high-risk clones of multi-drug resistant isolates, surveillance and proper infection control practices are crucial to prevent outbreaks and further spread into the community.

Elicitor mediated enhancement of shoot biomass and lupeol production in Hemidesmus indicus (L.) R. Br. ex. Schult. and Tylophora indica (Burm. F.) Merrill using yeast extract and salicylic acid.

Hemidesmus indicus (L.) R. Br. ex Schult. and Tylophora indica (Burm. F.) Merrill shoot cultures were treated with different concentrations of yeast extract (YE; 25-200 mg/L) and salicylic acid (SA; 50-200 µM), and their effect on lupeol production was assessed. The maximum dry weight (DW) biomass was recorded when H. indicus shoots were treated with SA (50 µM) and T. indica shoots with YE (200 mg/L). Highest lupeol yield (335.40 ± 0.04 µg/g DW) was obtained in H. indicus shoots after treatment with 50 µM of SA for 3 weeks. Whereas in T. indica, maximum lupeol content (584.26 ± 8.14 µg/g DW) was recorded by giving treatment with 25 µM of SA for 6 weeks.

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.

Trends of drug resistance to the commonly used antibiotics to combat the COVID-19 pandemic: Experience from a super-speciality institute of Northern India.

Purpose: Coronavirus disease 2019 (COVID-19) is purely a viral illness which is not affected by the usage of antibiotics, but the risk of development of secondary bacterial infections during the course of respiratory illness or hospitalisation has led to a surge of antibiotic use. Anti-microbial resistance has taken an upward trend to some of the commonly used or over-used antibiotics. The present study was planned to focus on the trends of resistance rates noticed for the common antibiotics, namely, doxycycline, azithromycin, and so on, before and after the advent of this pandemic. Material and Methods: The study was conducted at a tertiary care hospital of North India with 2000 samples, 1000 samples between March 2019 and March 2020 before the COVID pandemic and 1000 samples between April 2020 and April 2021 after the advent of the pandemic. Identification and zones for doxycycline and erythromycin were interpreted as per Clinical and Laboratory Standards Institute guidelines. Results: Among the various samples, pus/aspirated fluids were in majority (47%), followed by blood (29%), respiratory specimens (18%), and urine (6%). On stratifying the various pathogens associated with the treatment of doxycycline and erythromycin, Staphylococcus species were the predominant ones in almost 82% of the cases, followed by Enterococcus (12%) and Streptococcus (6%) species. For doxycycline, the overall sensitivity was noted to be 46% in the year 2019-20 and 31% in the year 2020-21, whereas for erythromycin, the sensitivity was seen as 39% in 2019-20 and dropped down to 26% in 2020-21. Conclusions: The authors noted a dip in the overall sensitivity towards doxycycline and azithromycin. This finding clearly indicates the increasing rates of antibiotic resistance in a developing country such as India during these COVID times. A proper anti-microbial stewardship programme during these times will help to de-escalate the increasing resistance rates and will prove to be of great help to the primary care physicians.

Burden of tyrosine kinase inhibitor failure in Chinese chronic myeloid leukemia patients: a systematic literature review.

Aim: To conduct a systematic literature review of real-world evidence on the burden of tyrosine kinase inhibitor (TKI) failure in Chinese patients with chronic myeloid leukemia (CML). Methods: We identified 155 references in Chinese- and English-language journals from 2001 to 2021. Results: The age-adjusted mortality rate in Chinese CML patients was decreasing. Imatinib treatment had a higher annual treatment failure risk than nilotinib (0.199 vs 0.041). Patients with TKI treatment failure tended to be young (median: 38.6 years), have progressive disease (44.3%) and harbor BCR-ABL1 mutations (51.6%). The disease burden of TKI treatment failure included reduced health outcomes and increased health resource utilization and costs. Conclusion: CML relapse cases could continuously rise in China due to increasing TKI treatment failure over extended survival.

HPLC and GC/MS analysis of Prunus ulmifolia Franch. (syn. Aflatunia ulmifolia (Franch.) Vassilcz.) leaves growing in South-Eastern Kazakhstan.

Prunus ulmifolia Franch. (Rosaceae) was investigated for its phytochemical composition from South-Eastern Kazakhstan for the first time. HPLC analysis confirmed rutin (0.88%) in ethanol extract, and the extract also exhibited antioxidant activity. The GC/MS analysis identified total 44 components from main groups e.g. oxygenated monoterpenes (51.06%), oxygenated sesquiterpenes (20.33%), non-terpene derivatives (18.71%), and sesquiterpene hydrocarbons (7.89%), and the maximum content was of acyclic alcoholic monoterpenoid citronellol (36.58%). The hierarchical cluster analysis (HCA) from previous reports and present study was used to demonstrate the variations between essential oil compositions in different Prunus species. It formed three main clusters, cluster I consisted of species with benzaldehyde as dominant component. Cluster II included plants with benzaldehyde as secondary component, and cluster III was of P. ulmifolia in which benzaldehyde was not detected. Further, the essential oil was assessed for cytotoxic and antimicrobial activities too, and it showed better cytotoxic but poor antimicrobial activities.

Bacterial coinfections in COVID: Prevalence, antibiotic sensitivity patterns and clinical outcomes from a tertiary institute of Northern India.

Purpose: Bacterial coinfections are a leading cause of morbidity and mortality during viral infections including corona virus disease (COVID-19). The COVID-19 pandemic has highlighted the need to comprehend the complex connection between bacterial and viral infections. During the current pandemic, systematic testing of the COVID-19 patients having bacterial coinfections is essential to choose the correct antibiotics for treatment and prevent the spread of antimicrobial resistance (AMR). This study was planned to study the prevalence, demographic parameters, comorbidities, antibiotic sensitivity patterns, and outcomes in hospitalized COVID-19 patients with bacterial coinfections. Material and Methods: The COVID-19 patients having bacterial coinfections were selected for the study and analyzed for the prevalence, antibiotic sensitivities, comorbidities, and clinical outcomes. The bacterial isolates were identified and the antibiotic susceptibility testing was performed according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. Results: Of the total 1,019 COVID-19 patients screened, 5.2% (n = 53) demonstrated clinical signs of bacterial coinfection. Escherichia coli were the most common isolate followed by Pseudomonas aeruginosa and Klebsiella spp. among the gram-negative bacterial infections. Coagulase-negative Staphylococcus species (CONS) and Staphylococcus aureus were most common among the gram-positive bacterial infections. The antibiotic sensitivity profiling revealed that colistin (99%), imipenem (78%), and fosfomycin (95%) were the most effective drugs against the gram-negative isolates while vancomycin (100%), teicoplanin (99%), and doxycycline (71%) were most potent against the gram-positive isolates. The analysis of the clinical parameters and outcomes revealed that among the COVID-19 patients with bacterial coinfections, the mortality rate was higher (39%) than the control group (17%) (P-value < 0.001). Conclusion: This study reveals the significantly increased rates of bacterial coinfections among COVID-19 patients which may lead to an increase in mortality. This study will guide the physicians at the primary level on the rational and correct usage of antibiotics in such COVID cases. Hence, systematic testing of COVID-19 patients with bacterial coinfections is the need of the hour to decrease the mortality rate and limit the spread of AMR.

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.