Colonies Of Strain Research Articles

Chronic Coinfection with Pseudomonas aeruginosa and Normal Colony Staphylococcus aureus Causes Lung Structural Damage in the Cystic Fibrosis Rat

Cystic fibrosis (CF) respiratory outcomes are heavily influenced by complications of infection. Pseudomonas aeruginosa and Staphylococcus aureus are the most common colonizers of the cystic fibrosis lung, and frequently overlap to cause chronic and persistent co-infections associated with severe disease. However, the dynamics of P. aeruginosa and S. aureus co-infection and its impacts on the development of CF lung structural damage are poorly understood. Additionally, small colony variants (SCVs) of S. aureus have been associated with P. aeruginosa infections in people with CF, but their role in disease progression is largely unknown. In this work, the CF rat was used to model chronic lung co-infection with P. aeruginosa and S. aureus, using clinical and laboratory derived normal colony and SCV strains of S. aureus to evaluate the impact of phenotype on clinical outcomes. Rats co-infected with clinically derived S. aureus of both phenotypes experienced increased inflammation in the lung, but only the combination of P. aeruginosa and clinical normal colony S. aureus led to lung structural decline, including mucus obstruction and bronchiectasis. In regression analyses, damage was associated with a higher burden of P. aeruginosa, indicating that chronic co-infection with normal colony S. aureus and P. aeruginosa may support the progression CF lung decline driven by P. aeruginosa, which might be avoided when co-infecting S. aureus exhibits the SCV phenotype.

Characterization of a Salmonella enterica serovar Typhimurium lineage with rough colony morphology and multidrug resistance

Salmonella enterica serovar Typhimurium (S. Typhimurium) is a major cause of salmonellosis, and the emergence of multidrug-resistant pathovariants has become a growing concern. Here, we investigate a distinct rough colony variant exhibiting a strong biofilm-forming ability isolated in China. Whole-genome sequencing on 2,212 Chinese isolates and 1,739 publicly available genomes reveals the population structure and evolutionary history of the rough colony variants. Characterized by macro, red, dry, and rough (mrdar) colonies, these variants demonstrate enhanced biofilm formation at 28 °C and 37 °C compared to typical rdar colonies. The mrdar variants exhibit extensive multidrug resistance, with significantly higher resistance to at least five classes of antimicrobial agents compared to non-mrdar variants. This resistance is primarily conferred by an IncHI2 plasmid harboring 19 antimicrobial resistance genes. Phylogenomic analysis divides the global collections into six lineages. The majority of mrdar variants belong to sublineage L6.5, which originated from Chinese smooth colony strains and possibly emerged circa 1977. Among the mrdar variants, upregulation of the csgDEFG operons is observed, probably due to a distinct point mutation (−44G > T) in the csgD gene promoter. Pangenome and genome-wide association analyses identify 87 specific accessory genes and 72 distinct single nucleotide polymorphisms associated with the mrdar morphotype.

Phycosphere bacterial composition and function in colony and solitary Phaeocystis globosa strains providing novel insights into the algal blooms

Phycosphere bacteria can regulate the dynamics of different algal blooms that impact marine ecosystems. Phaeocystis globosa can alternate between solitary free-living cells and colonies and the latter morphotype is dominate during blooms. The mechanisms underlying the formation of these blooms have received much attention. High throughput sequencing results showed that the bacterial community composition differed significantly between colony and solitary strains in bacterial composition and function. It was found that the genera SM1A02 and Haliea were detected only among the colony strains and contribute to ammonium accumulation in colonies, and the genus Sulfitobacter was abundant among the colony strains that were excellent at producing DMS. In addition, the bacterial communities of the two colony strains exhibited stronger abilities for carbon and sulfur metabolism, energy metabolism, vitamin B synthesis, and signal transduction, providing inorganic and organic nutrients and facilitating tight communication with the host algae, thereby promoting growth and bloom development.

A Case Report on Product Rotation to Manage Severe Lysinibacillus sphaericus Resistance in Culex pipiens from Salt Lake City, Utah.

The Salt Lake City Mosquito Abatement District (SLCMAD) detected a 20,000-fold resistance to Lysinibacillus sphaericus (Lsph) in Culex pipiens occurring in catch basins of Salt Lake City during 2016. In response, SLCMAD suspended use of Lsph and rotated use of spinosyn and s-methoprene products for the next three years. At the end of the third year, Lsph was evaluated again and efficacy similar to susceptible colony strains. During the second year of Lsph use, technicians observed lack of control of larvae at some urban sites. Bioassays performed during 2021 showed recurrence of some resistance to Lsph to varying degrees across SLCMAD urban areas. The rapidity with which resistant phenotypes reemerged clarifies that SLCMAD cannot in the near future rely on repeated use of Lsph, even after suspending use for three years and using within-season product rotations. Prior reports in other research groups have found long-term selection to Lsph, as is the case at SLCMAD, to not regress in spite of halting use of the products. However, our findings offer some optimism that regression may be relatively quick. More operational review is needed, and future work should characterize resistance alleles in field populations. Collectively, there is a lack of concrete data supporting the prevailing assumptions from adjacent industries that were adopted into mosquito abatement. We provide this short note as additional guidance for mosquito and vector control districts weighing options to remediate Lsph resistance.

Effect of larval handling on black soldier fly life history traits and bioconversion efficiency.

The black soldier fly is considered the most promising insect species for mass production; however, information on the effects of handling, which is unavoidable during experimental trials and rearing practices, is still limited. To address this gap, three different manipulation intensities were tested on 100 6-day-old larvae per replica (6 replicates/treatments) fed on Gainesville diet: (1) hard-handled (HH), larvae underwent continuous manipulation until the end of larval stage, (2) soft-handled (SH), larvae were manipulated after the appearance of the first prepupa, (3) no-handled (NH), larvae remained untouched. Every 4 days from the beginning to the end of the larval stage, the manipulations lasted 30 min and occurred under laboratory conditions (20°C). During the sampling operations, at least 30 larvae were randomly extracted, washed, dried, and weight-mimicked. At the end of larval stage, all the boxes remained untouched until the adult fly stage, and the emergency rate and sex ratio were evaluated on dead flies. Data were statistically analyzed using IBM SPSS V20.0.0 software and the considered significance level was p < 0.05. The larval stage lasted 8.2 days for both HH and SH (p > 0.05). Despite the HH larvae being the most manipulated, no difference was also observed in final weight (HH, 160 mg; SH, 150 mg; p > 0.05) and survival rate (HH, 96.2%; SH, 94.5%; p > 0.05). The manipulation did not influence the bioconversion capacity of the larvae (bioconversion efficiency corrected for the residue: HH, 14.3%; SH, 12.91%; reduction rate: HH, 58.4%; SH, 55.9%; waste reduction index: HH, 7.28%/day; SH, 7.25%/day; p > 0.05). Finally, the development time from larva to fly (about 20.7; p > 0.05), the emergency rate (NH: 92.8%; SH: 89.5%; HH: 82.7%) and sex ratio (~1.2% to male flies) were not affected by the handling (p > 0.05). In conclusion, the handling procedures used in the current study did not influence the life history traits of the black soldier fly. However, further studies are needed to evaluate if different experimental protocols on various scales, the colony strain or other handling procedures may suggest a different scenario or confirm the results.

Evaluation of An Aerial Application of Duet Hd® Against Aedes Dorsalis and Culex Tarsalis in Rural Habitats of the Great Salt Lake, Utah.

The Salt Lake City Mosquito Abatement District (SLCMAD) has been conducting aerial applications using an organophosphate insecticide against adult mosquitoes for several decades. In order to evaluate a potential rotation product, aerial applications of Duet HD™, a pyrethroid, were conducted under operational conditions against wild populations of Aedes dorsalis and Culex tarsalis and against colony strains of Cx. pipiens and Cx. quinquefasciatus. The erratic wind patterns of the greater Salt Lake area did not prevent sufficient droplet deposition flux at 9 monitoring locations spread across a 5,120-acre (2,072 ha) spray block within rural habitats. Three separate aerial application trials showed great efficacy against Ae. dorsalis. In contrast, Cx. tarsalis exhibited inconsistent treatment-associated mortalities, suggesting the presence of less susceptible or resistant field populations as a result of spillover from agricultural or residential pyrethroid usage. Bottle bioassays to diagnose pyrethroid resistance using field-collected Cx. tarsalis indicated that some populations of this species, especially those closest to urban edges, failed to show adequate mortality in resistance assays. Despite challenging weather conditions, Duet HD worked reasonably well against susceptible mosquito species, and it may provide a crucial role as an alternative for organophosphate applications within specific and sensitive areas. However, its area-wide adoption into control applications by the SLCMAD could be problematic due to reduced impacts on the most important arboviral vector species, Cx. tarsalis, in this area. This study demonstrates the importance of testing mosquito control products under different operational environments and against potentially resistant mosquito populations by municipal mosquito control districts.

Comparative Analysis of Sampling Methods for Assessing Bacterial Contamination on Hospital Partition Curtains: Moistened Swabs versus RODAC Agar Plates.

BACKGROUND Partition curtains are one of the main sources of nosocomial infection in the hospital environment. However, there are no unified standards for monitoring medical textiles across different countries or regions. This study aimed to investigate the accuracy of 2 different sampling methods - swabbing vs RODAC (replicate organism detection and counting) agar plate - in terms of detection of bacterial contamination, and their suitability as monitoring methods for partition curtains and other medical textiles. MATERIAL AND METHODS A total of 24 partition curtains were selected by stratified random sampling. The swabbing technique and RODAC agar plates were the chosen sampling methods. The number of colony-forming units was calculated and colony morphologies and strains on the plates were observed and identified after culturing. RESULTS A total of 192 samples were collected. Of them, 161 pathogenic strains were isolated via the swabbing technique and 309 pathogenic strains were isolated using the RODAC agar plates. The swabbing technique had a higher proportion for gram-positive bacteria (P=0.0004), while RODAC agar plates had a higher proportion for gram-negative bacteria (P=0.72). The detection of bacterial contamination rates using the swabbing technique was superior to that of the RODAC agar plate method (P<0.001). CONCLUSIONS The swabbing technique offers more advantages in terms of detection of bacterial contamination rates and gram-positive bacteria, while the RODAC agar plate is more sensitive for detection of gram-negative bacteria.

Variation in Susceptibility to Permethrin in Culex pipiens and Culex restuans Populations in the Great Lakes Region of the United States.

Two Culex pipiens form Pipiens colony strains and a field population of Cx. restuans from Michigan were susceptible and a Cx. pipiens form Molestus colony strain was comparatively less susceptible to a dose of 43 μg/ml of permethrin in Centers for Disease Control and Prevention (CDC) bottle bioassays. Using this diagnostic dose and these populations as controls, adult female Cx. pipiens and Cx. restuans were reared from egg rafts from 28 sites in Illinois, Ohio, Michigan, Iowa, Indiana, Wisconsin, and Minnesota. Tested mosquitoes showed high mortality in populations from 12 sites, less mortality (90-96%) at 9 sites, and less than 90% mortality from 7 sites during 30-min exposures. However, all tested populations showed 97-100% mortality at 60 min, indicating low phenotypic penetrance of resistance factors. These results indicate variation in susceptibility to permethrin in populations of West Nile virus vectors in the Great Lakes region of the United States, with evidence of modest resistance at 7 of 28 (25%) of the sampled populations.

Insecticide resistant Anopheles gambiae have enhanced longevity but reduced reproductive fitness and a longer first gonotrophic cycle

Widespread insecticide resistance in African malaria vectors raises concerns over the potential to compromise malaria vector control interventions. Understanding the evolution of resistance mechanisms, and whether the selective disadvantages are large enough to be useful in resistance management or designing suitable control strategies is crucial. This study assessed whether insecticide resistance to pyrethroids has an effect on the gonotrophic cycle and reproductive potential of malaria vector Anopheles gambiae. Comparative tests were performed with pyrethroid-resistant and susceptible colonies of Anopheles gambiae colonized from the same geographical area, and the reference Kisumu strain was used as a control. Adult females aged 3 days old were given a blood meal and kept separately for individual egg-laying. The number of days taken to lay eggs post-blood-feeding was recorded to determine the length of the gonotrophic cycle. To measure adult longevity and reproduction potential, newly emerged males and females of equal numbers were aspirated into a cage and females allowed to blood feed daily. The number of eggs laid and the surviving mosquitoes were recorded daily to determine fecundity, net reproduction rate, intrinsic growth rate and adult longevity. Overall, the resistant females had a significantly longer (1.8 days) gonotrophic cycle than susceptible females (F2, 13 = 9. 836, P < 0.01). The proportion of resistant females that laid eggs was lower 31.30% (94/300) compared to 54% (162/300) in the susceptible colony and 65.7% (197/300) in the Kisumu strain. The mean number of eggs laid per female was significantly lower in the resistant colony (88.02 ± 20) compared to the susceptible colony (104.9 ± .28.8) and the Kisumu strain (97.6 ± 34.8). The adult longevity was significantly higher for resistant (39.7 ± 1.6 days) compared to susceptible (29.9 ± 1.7 days) and the Kisumu strain was (29.6 ± 1.1 days) (F2,8 = 45.05, P < 0.0001). Resistant colony exhibited a lower fecundity (4.3 eggs/females/day) and net reproductive rate (2.6 offsprings/female/generation) compared to the susceptible colony (8.6 eggs/female/day; 4.7 offsprings/female/generation respectively) and Kisumu strain (9.7 eggs/female/day; 4.1 offsprings/female/generation respectively). The study suggests high fitness cost on reproductive parameters of pyrethroid-resistant mosquitoes particularly on the duration of gonotrophic cycle, fecundity and net reproductive rate. These fitness costs are likely associated with maintaining both target site and metabolic mechanisms of resistance to pyrethroids. Despite these costs, resistant mosquitoes had longer longevity. These results give insights to understanding the fitness cost of insecticide resistance and thus are critical when predicting the epidemiological impact of insecticide resistance.

Rapid screening of microalgae by a 96-hole air-flowing device.

In this study, a 96-hole air-flowing device (96HAFD) was established for high-throughput screening of three mutant Chlorella strains under air aeration. 96HAFD was first tested for the confirmation of homogeneous air aeration cultivation environment at 1.2L min-1 for algal screening based on the results of t test (p < 0.05) in the verification of consistency experiment. Then the data of dynamic growth characteristics of three mutant Chlorella strains indicated the good agreement in three screening devices including 96HAFD, flask and tube air-flowing cultivation devices by linear regression analysis between the 96HAFD and tube (R2 = 0.9904), 96HAFD and flask (R2 = 0.9904). At last, the 96HAFD was verified more efficient and reliable in fast screening single algal colony strains when compared with flask and tube air-flowing cultivation devices, because 96HAFD was confirmed have better performances in adaptation to the aeration cultivation circumstance and growing faster in a short period, in addition, 96HAFD had the less percentage of water loss per day (0.11%) than that of flask aeration device (2-3%) and tube aeration device (5-6.5%), which reduced negative effect caused by the water evaporation in the aeration cultivation to make the whole growing system more stable.

The influence of culture-dependent native microbiota in Zika virus infection in Aedes aegypti

BackgroundEmerging and re-emerging vector-borne diseases (VBDs) pose a recurring threat to tropical countries, mainly due to the abundance and distribution of the Aedes aegypti mosquito, which is a vector of the Zika, dengue, chikungunya, and yellow fever arboviruses.MethodsFemale 3–5 day-old Ae. aegypti were distributed into two experimental groups: group I—survey of cultivable bacteria; sucrose group: fed only on sucrose, i.e., non-blood-fed (UF); blood-fed group: (i) fed with non-infected blood (BF); (ii) fed with blood infected with the Zika virus (BZIKV); (iii) pretreated with penicillin/streptomycin (pen/strep), and fed with non-infected blood (TBF); (iv) pretreated with pen/strep and fed blood infected with ZIKV, i.e., gravid with developed ovaries, (TGZIKV); group II—experimental co-infections: bacteria genera isolated from the group fed on sucrose, i.e., non-blood-fed (UF).ResultsUsing the cultivable method and the same mosquito colony and ZIKV strain described by in a previous work, our results reveled 11 isolates (Acinetobacter, Aeromonas, Cedecea, Cellulosimicrobium, Elizabethkingia, Enterobacter, Lysinibacillus, Pantoea, Pseudomonas, Serratia, and Staphylococcus). Enterobacter was present in all evaluated groups (i.e., UF, BF, BZIKV, TBF, and TGZIKV), whereas Elizabethkingia was present in the UF, BZIKV, and TBF groups. Pseudomonas was present in the BZIKV and TBF groups, whereas Staphylococcus was present in the TBF and TGZIKV groups. The only genera of bacteria that were found to be present in only one group were Aeromonas, Lysinibacillus, and Serratia (UF); Cedacea, Pantoea and Acinetobacter (BF); and Cellulosimicrobium (BZIKV). The mosquitoes co-infected with ZIKV plus the isolates group fed on sucrose (UF) showed interference in the outcome of infection.ConclusionsWe demonstrate that the distinct feeding aspects assessed herein influence the composition of bacterial diversity. In the co-infection, among ZIKV, Ae. aegypti and the bacterial isolates, the ZIKV/Lysinibacillus–Ae. aegypti had the lowest number of viral copies in the head-SG, which means that it negatively affects vector competence. However, when the saliva was analyzed after forced feeding, no virus was detected in the mosquito groups ZIKV/Lysinibacillus–Lu. longipalpis and Ae. aegypti; the combination of ZIKV/Serratia may interfere in salivation. This indicates that the combinations do not produce viable viruses and may have great potential as a method of biological control.Graphical

Characterization of resistance profile (intensity and mechanisms) of Anopheles gambiae in three communes of northern Benin, West Africa

BackgroundThe selection and the spread of insecticide resistance in malaria vectors to the main classes of insecticides used in vector control tools are a major and ongoing challenge to malaria vector control programmes. This study aimed to determine the intensity of vector resistance to insecticides in three regions of Benin with different agro-ecological characteristics.MethodsLarvae of Anopheles gambiae sensu lato (s.l.) were collected from September to November 2017 in different larval sites in three northern Benin communes: Parakou, Kandi and Malanville. Two to five-day-old, non-blood-fed, female mosquitoes were exposed to papers impregnated with deltamethrin, permethrin and bendiocarb at dosages of 1 × the diagnostic dose, 5 × and 10 × to determine the intensity of resistance in these vectors. Molecular frequencies of the kdr L1014F and ace-1R G119S insecticide resistance mutations and levels of detoxification enzymes were determined for mosquitoes sampled at each study site.ResultsResistance to pyrethroids (permethrin and deltamethrin) was recorded in all three communes with mortality rates below 60% using the diagnostic dose (1x). The results obtained after exposure of An. gambiae to permethrin 10 × were 99% in Kandi, 98% in Malanville and 99% in Parakou. With deltamethrin 10x, mortality rates were 100% in Kandi, 96% in Malanville and 73% in Parakou. For the diagnostic dose of bendiocarb, suspected resistance was recorded in the communes of Malanville (97%) and Kandi (94%) while sensitivity was observed in Parakou (98%).Using the 10 × dose, mortality was 98% in Kandi, 100% in Malanville and 99% in Parakou. The frequencies of the kdr L1014F allele varied between 59 and 83% depending on the sites and species of the An. gambiae complex, while the frequency of the ace-1R G119S gene varied between 0 and 5%. Biochemical tests showed high levels of oxidase and esterase activity compared to the susceptible colony strain of An. gambiae sensu stricto (Kisumu strain).ConclusionAnopheles gambiae showed a generalized loss of susceptibility to permethrin and deltamethrin but also showed moderate to high intensity of resistance in different regions of Benin. This high intensity of resistance is a potential threat to the effectiveness of vector control.

A NEW LABORATORY COLONIZATION OF AEDES AEGYPTI AFTER REEMERGENCE AND UNSUCCESSFUL ERADICATION IN ST. AUGUSTINE, FLORIDA

After unsuccessful eradication attempts against Aedes aegypti (L.) following a sudden re-emergence in St. Augustine, Florida in early 2016; a new locally acquired colony strain of Ae. aegypti was established at the Anastasia Mosquito Control District (AMCD) in June 2017. Aedes aegypti adults were maintained in cages at the AMCD insectary. Larval and adult mosquitoes were collected from downtown St. Augustine, Florida. Female mosquitoes at 5-7 days old were fed upon the exposed forearm of human volunteers in the 1 st and 2 nd generations. Mating was observed in a large cage and confirmed with eggs deposited on wet filter paper in ovicups. Over 90% egg hatch was observed in the laboratory. The new colony strain of Ae. aegypti has been cataloged at the USDA, Center for Medical, Agricultural, and Veterinary Entomology facility in Gainesville, FL and is being used to further research and control this species across North Florida.

Serological detection of brucellosis among febrile, malaria-negative children and domesticated dogs in an urban African setting.

BackgroundChildhood brucellosis and malaria are co-endemic febrile illnesses in some sub-Saharan African countries. Malaria and brucellosis co-infection or brucellosis sole infections are often missed due to an over emphasis on malaria and the lack of appropriate diagnostic infrastructure. Brucellosis in dogs is usually overlooked and yet there is extensive contact between humans and their pets.ObjectiveThis study investigated brucellosis in children and dogs using a confirmatory serological testing series that screens for three Brucella sp.MethodsResidual blood samples from malaria smear-negative febrile children were collected and tested for Brucella sp and malaria parasite. During the same period, residual blood samples presented to a veterinary microbiology laboratory in the same area were tested for brucellosis using the same approach.ResultsA total of 105 human and 80 canine blood samples were tested for brucellosis antibodies. The seroprevalence of brucellosis was 22.86% (25/105) in children and 1.3% (1/80) in dogs using the Card, buffered acidified plate antigen, and standard plate agglutination tests but was 0% using the rivanol precipitation plate agglutination test.ConclusionGiven that brucellosis can be caused by both smooth and rough colony strains, there is a need to modify the current serological surveillance strategy (targeted at only Brucella abortus and other smooth colony Brucella strains) to figure out the relative contribution of rough colony Brucella strains (B. ovis and B. canis). Since Uganda is endemic for brucellosis there is a need to modify the brucellosis surveillance strategy.

EFFECT OF SOME INSECTICIDES ON RESISTANCE LEVEL AND CERTAIN BIOCHEMICAL ASPECTS IN Ceratitis Capitata (DIPTERA: TEPHRITIDEA) FROM DIFFERENT LOCALITIES IN EGYPT

To estimate toxic actions of two insecticides on {lambda-cyhalothrin (Karilot gold 5%EC) and the biopesticide spinosad, (Conserve 0.24%CB)}, adults of the laboratory strain of Mediterranean fruit fly, Ceratitis capitata (Wied.) were treated with different concentrations. Discriminating value (LC99) was selected for monitoring resistance in three field populations collected from different governorates (Qaluobia, Behira and Sharkia). Data showed that, males of laboratory strain as well as field colony strains were more susceptible than females. Qaluobia field colony exhibited the highest resistance level to lambda-cyhalothrin followed by Sharkia and Behira colonies in both male and female flies comparing with laboratory strain. Sharkia colony showed remarkable higher level of resistance to spinosad in males and females more than Behira and Qaluobia colonies. On the other hand, Ceratitis capitata flies of the different field strains showed remarked higher levels of the enzymes activity than the laboratory strain. Males showed the highest levels of acid phosphatase in Qaluobia, whereas Sharkia showed the highest level in females. The levels of alkaline phosphatase were higher in Qaluobia followed by Behira and Sharkia in both sexes. Behira had the highest enzymatic activity of AChE in male and female flies. The levels of total protein were higher in Behira than the other field colonies in males, but Sharkia exhibited the highest level in case of female flies. This means that the enzymatic activities play an important role in the insect resistance to spinosad and lambda-cyhalothrin, and there were positive correllation between resistance levels and enzymatic activity in the different field colonies.

Type I interferon induced by TLR2-TLR4-MyD88-TRIF-IRF3 controls Mycobacterium abscessus subsp. abscessus persistence in murine macrophages via nitric oxide

Mycobacterium abscessus (MAB) is an emerging, rapidly growing non-tuberculous Mycobacterium causing therapy-resistant pulmonary disease especially in patients with cystic fibrosis (CF). Smooth and rough colony type MAB can be isolated from infected patients whereby rough colony type MAB are more often associated with severe disease. Disease severity is also associated with an alternated type I interferon (IFN-I) response of the MAB-infected patients. However the relevance of this response for the outcome of MAB infection is still unknown. In this study, we analyzed the IFNβ expression of murine macrophages infected with a MAB rough colony strain (MAB-R) isolated from a patient with progressive CF and compared it to macrophages infected with the MAB smooth colony type reference strain (MAB-S). We found that MAB-R infected macrophages expressed significantly more IFNβ mRNA and protein than MAB-S infected macrophages. Higher IFNβ induction by MAB-R was associated with higher TNF expression and intracellular killing while low IFNβ induction was associated with lower TNF expression and persistence of MAB-S. IFNβ induction was independent of the intracellular cGAS-STING recognition pathway. MAB appeared to be recognized extracellularly and induced IFNβ expression via TLR2-TLR4-MyD88-TRIF-IRF3 dependent pathways. By using macrophages lacking the IFN-I receptor we demonstrate that MAB induced IFN-I response essentially contributed to restricting MAB-R and MAB-S infections by activating macrophage Nos2 expression and nitric oxide production. Thus IFN-I seem to influence the intrinsic ability of macrophages to control MAB infections. As MAB persists over long time periods in susceptible patients, our findings suggest that virulence of MAB strains is promoted by an insufficient IFN-I response of the host.

Studies on the Genetic Variations between Field Strains of Pectinophora gossypiella (SAUNDERS) using Polymerase Chain Reaction (PCR) Technique

Five different strains of the pink bollworm, Pectinophora gossypiella (Saunders) were used in the present study.The laboratory strain was used as a baseline in the molecular biology assays. Four strains were selected from natural popoulations, fields located in Qalubia, Gharbia, Menoufia and Kafr-Elsheikh Governorates. The molecular studies included the analysis of the plod genomic DNA of the tested strains under this study by using Random Amplified Polymorphic DNA (RAPD) method. A battery of five primers was used to evaluate the mutagenic differentiation among the five strains. The primer S4 generated the highest numbers of fragments (32 fragments). Both primers K15 and S8 generated 23 fragments. The lowest number of fragments appeared in primer C15 and primer P8, (18 fragments). The molecular sizes of fragments ranged between 180 and 1182bp. The RAPD patterns resulted from amplification of DNA of the field colony strains and laboratory strain of the pink bollworm P. gossypiella revealed that the lowest value of similarity index (0.0%), which reflects the highest degree of change in DNA structure and sequences between the genomes of laboratory pink bollworm and those exposed to a wide spread of different insecticides for controlling the pest in the fields. On the other hand, there is no compilitily similarity index between field strains and laboratory strain of pink bollworm. The highest similarity index between field strains and laboratory strain of the pink bollworm appeared in primer P8, while the lowest similarity index between field strains and laboratory strain of the pink bollworm appeared in primer K15. The primer S4 recorded that is no similarity index between Qalubia strain and each of laboratory and field strains. It is interrest to note that the less damaging effect to pink bollworm DNA could be attributed to a good detoxifying mechanism developed by the insect as a result of wide spread and long term exposure of insect larvae in additional to different thermal degrees in the fields

ACTIVITY OF HYDROLYSIS ENZYMES IN DIFFERENT INSTAR LARVAE OF THE AMERICAN BOLLWORM, HELICOVERPA ARMIGERA (HUBNER)

Enzymes activity included acetylcholinesterase, non-specific α and β- esterases and alkaline phosphatase were determined calorimetrically in the whole homogenates of the different instar larvae; 3rd, 4th, 5th and 6th of the field strain as well as the baseline, laboratory strain of American bollworm, Helicoverpa armigera. The results indicated that the enzymes activity levels in the different instar larvae of the field strain were markedly higher than that in the laboratory strain at the respective instar larvae. The enzymatic activity levels increased steady from the 3rd to the 6th instar larvae. A sharp increase in the enzymatic activity levels were determined in the 6th instar larvae. The average levels of the enzymatic activity in both field colony and laboratory strain were 11.630 and 3.627 µg acetyl bromide released / min. /individual for A.Ch.E.; 8.819 and 3.430 µg α-naphthol released/ min/ individual and the corresponding values were ranged between 5.232 and 3.218 µg β– naphthol released / min/ larva for beta esterase; respectively and157.669 and 50.428 unit X 103/larva for alkaline phosphatase; respectively

Characterisation of Species and Diversity of Anopheles gambiae Keele Colony

Anopheles gambiae sensu stricto was recently reclassified as two species, An. coluzzii and An. gambiae s.s., in wild-caught mosquitoes, on the basis of the molecular form, denoted M or S, of a marker on the X chromosome. The An. gambiae Keele line is an outbred laboratory colony strain that was developed around 12 years ago by crosses between mosquitoes from 4 existing An. gambiae colonies. Laboratory colonies of mosquitoes often have limited genetic diversity because of small starting populations (founder effect) and subsequent fluctuations in colony size. Here we describe the characterisation of the chromosomal form(s) present in the Keele line, and investigate the diversity present in the colony using microsatellite markers on chromosome 3. We also characterise the large 2La inversion on chromosome 2. The results indicate that only the M-form of the chromosome X marker is present in the Keele colony, which was unexpected given that 3 of the 4 parent colonies were probably S-form. Levels of diversity were relatively high, as indicated by a mean number of microsatellite alleles of 6.25 across 4 microsatellites, in at least 25 mosquitoes. Both karyotypes of the inversion on chromosome 2 (2La/2L+a) were found to be present at approximately equal proportions. The Keele colony has a mixed M- and S-form origin, and in common with the PEST strain, we propose continuing to denote it as an An. gambiae s.s. line.

IP3 accumulation and/or inositol depletion: two downstream lithium's effects that may mediate its behavioral and cellular changes.

Lithium is the prototype mood stabilizer but its mechanism is still unresolved. Two hypotheses dominate—the consequences of lithium's inhibition of inositol monophosphatase at therapeutically relevant concentrations (the ‘inositol depletion' hypothesis), and of glycogen-synthase kinase-3. To further elaborate the inositol depletion hypothesis that did not decisively determine whether inositol depletion per se, or phosphoinositols accumulation induces the beneficial effects, we utilized knockout mice of either of two inositol metabolism-related genes—IMPA1 or SMIT1, both mimic several lithium's behavioral and biochemical effects. We assessed in vivo, under non-agonist-stimulated conditions, 3H-inositol incorporation into brain phosphoinositols and phosphoinositides in wild-type, lithium-treated, IMPA1 and SMIT1 knockout mice. Lithium treatment increased frontal cortex and hippocampal phosphoinositols labeling by several fold, but decreased phosphoinositides labeling in the frontal cortex of the wild-type mice of the IMPA1 colony strain by ~50%. Inositol metabolites were differently affected by IMPA1 and SMIT1 knockout. Inositoltrisphosphate administered intracerebroventricularly affected bipolar-related behaviors and autophagy markers in a lithium-like manner. Namely, IP3 but not IP1 reduced the immobility time of wild-type mice in the forced swim test model of antidepressant action by 30%, an effect that was reversed by an antagonist of all three IP3 receptors; amphetamine-induced hyperlocomotion of wild-type mice (distance traveled) was 35% reduced by IP3 administration; IP3 administration increased hippocampal messenger RNA levels of Beclin-1 (required for autophagy execution) and hippocampal and frontal cortex protein levels ratio of Beclin-1/p62 by about threefold (p62 is degraded by autophagy). To conclude, lithium affects the phosphatidylinositol signaling system in two ways: depleting inositol, consequently decreasing phosphoinositides; elevating inositol monophosphate levels followed by phosphoinositols accumulation. Each or both may mediate lithium-induced behavior.